研究者紹介システム

PRIHARDI Kahar
プリハルディ カハル
大学院工学研究科 応用化学専攻
准教授
農芸化学関係
Last Updated :2022/06/23

研究者情報

所属

  • 【主配置】

    大学院工学研究科 応用化学専攻

学位

  • 博士(農学), 岐阜大学

研究活動

研究分野

  • ライフサイエンス / 応用生物化学

受賞

  • 2004年 International Symposium on Biological Polyesters (ISBP), The Prominent Poster Award, Effective Production and Kinetic Characteristic of Ultra-high-molecular-weight of PHB in Recombinant Escherichia coli

    PRIHARDI KAHAR

    中華人民共和国

    国際学会・会議・シンポジウム等の賞

論文

  • Prihardi Kahar, Nova Rachmadona, Radityo Pangestu, Rendi Palar, Deddy Triyono Nugroho Adi, Ario Betha Juanssilfero, Yopi, Immanuel Manurung, Shinji Hama, Chiaki Ogino

    Each year, the palm oil industry generates a significant amount of biomass residue and effluent waste; both have been identified as significant sources of greenhouse gas (GHG) emissions. This issue poses a severe environmental challenge for the industry due to the possibility of long-term negative effects on human well-being. The palm-oil industry must invest significantly in the technology that is required to resolve these issues and to increase the industry's sustainability. However, current technologies for converting wastes such as lignocellulosic components and effluents into biochemical products are insufficient for optimal utilization. This review discusses the geographical availability of palm-oil biomass, its current utilization routes, and then recommends the development of technology for converting palm-oil biomass into value-added products through an integrated biorefinery strategy. Additionally, this review summarizes the palm oil industry's contribution to achieving sustainable development goals (SDGs) through a circular bioeconomy concept.

    2021年11月02日, Bioresource technology, 126266 - 126266, 英語, 国際誌

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    研究論文(学術雑誌)

  • Hideo Kawaguchi, Kenji Takada, Taghreed Elkasaby, Radityo Pangestu, Masakazu Toyoshima, Prihardi Kahar, Chiaki Ogino, Tatsuo Kaneko, Akihiko Kondo

    Lignocellulosic biomass has great potential as an inedible feedstock for bioplastic synthesis, although its use is still limited compared to current edible feedstocks of glucose and starch. This review focuses on recent advances in the production of biopolymers and biomonomers from lignocellulosic feedstocks with downstream processing and chemical polymer syntheses. In microbial production, four routes composed of existing poly (lactic acid) and polyhydroxyalkanoates (PHAs) and the emerging biomonomers of itaconic acid and aromatic compounds were presented to review present challenges and future perspectives, focusing on the use of lignocellulosic feedstocks. Recently, advances in purification technologies decreased the number of processes and their environmental burden. Additionally, the unique structures and high-performance of emerging lignocellulose-based bioplastics have expanded the possibilities for the use of bioplastics. The sequence of processes provides insight into the emerging technologies that are needed for the practical use of bioplastics made from lignocellulosic biomass.

    2021年10月22日, Bioresource technology, 126165 - 126165, 英語, 国際誌

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    研究論文(学術雑誌)

  • High enzymatic recovery and purification of xylooligosaccharides from empty fruit bunch via nanofiltration

    Hans Wijaya, Kengo Sasaki, Prihardi Kahar, Nanik Rahmani, Euis Hermiati, Yopi, Chiaki Ogino, Bambang Prasetya, Akihiko Kondo

    2020年05月, Processes, 8, 619, 英語

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    研究論文(学術雑誌)

  • Concentration of Lipase from Aspergillus oryzae Expressing Fusarium heterosporum by Nanofiltration to Enhance Transesterification

    Hans Wijaya, Kengo Sasaki, Prihardi Kahar, Emmanuel Quayson, Nova Rachmadona, Jerome Amoah, Shinji Hama, Chiaki Ogino, Akihiko Kondo

    2020年04月, Processes, 8 (4), 450, 英語

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    研究論文(学術雑誌)

  • High cell density cultivation of Lipomyces starkeyi for achieving highly efficient lipid production from sugar under low C/N ratio

    Rezky Lastinov Amza, Prihardi Kahar, Ario Betha Juanssilfero, Nao Miyamoto, Hiromi Otsuka, Chie Kihira, Chiaki Ogino, Akihiko Kondo

    2019年09月, Biochemical Engineering Journal, 149 (15), 107236, 英語

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    研究論文(学術雑誌)

  • Jerome Amoah, Prihardi Kahar, Chiaki Ogino, Akihiko Kondo

    Biorefinery has been suggested to provide relevant substitutes to a number of fossil products. Feedstocks and conversion technologies have, however, been the bottleneck to the realization of this concept. Herein, feedstocks and bioconversion technologies under biorefinery have been reviewed. Over the last decade, research has shown possibilities of generating tens of new products but only few industrial implementations. This is partly associated with low production yields and poor cost-competitiveness. This review addresses the technical barriers associated with the conversion of emerging feedstocks into chemicals and bioenergy platforms and summarizes the developed biotechnological approaches including advances in metabolic engineering. This summary further suggests possible future advances that would expand the portfolio of biorefinery and speed up the realization of biofuels and biochemicals.

    2019年06月, Biotechnology Journal, 14 (6), 1800494, 英語, 国際誌

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    研究論文(学術雑誌)

  • Rahmani N, Kahar P, Lisdiyanti P, Lee J, Yopi, Prasetya B, Ogino C, Kondo A

    A novel strategy for the low-cost, high-yield co-production of xylose and xylooligosaccharides together with no xylose inhibition was developed using a novel heterologous expression of XYN10Ks_480 endo-1,4-β-xylanase with a ricin-type β-trefoil type of domain and XYN11Ks_480 endo-1,4-β-xylanase with a CBM 2 superfamily from the Kitasatospora sp in an actinomycetes expression system. Xylose is the main building block for hemicellulose xylan. Our findings demonstrated high levels of expression and catalytic activity for XYN10Ks_480 during hydrolysis of the extracted xylan of bagasse, and three types of xylan-based substrates were used to produce xylose and xylooligosaccharides. However, hydrolysis by XYN11Ks_480 produced xylooligosaccharides without xylose formation. This study demonstrated how integrating sodium hypochlorite-extracted xylan and enzymatic hydrolysis could provide an alternative strategy for the generation of XOS from lignocellulosic material.

    2019年01月, Bioresource technology, 272, 315 - 325, 英語, 国際誌

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    研究論文(学術雑誌)

  • Juanssilfero AB, Kahar P, Amza RL, Yopi, Sudesh K, Ogino C, Prasetya B, Kondo A

    The ability of oleaginous yeast Lipomyces starkeyi to efficiently produce lipids when cultivated on sap extracted from felled oil palm trunk (OPT) as a novel inexpensive renewable carbon source was evaluated. OPT sap was found to contain approximately 98 g/L glucose and 32 g/L fructose. Batch fermentations were performed using three different OPT sap medium conditions: regular sap, enriched sap, and enriched sap at pH 5.0. Under all sap medium conditions, the cell biomass and lipid production achieved were approximately 30 g/L and 60% (w/w), respectively. L. starkeyi tolerated acidified medium (initial pH ≈ 3) and produced considerable amounts of ethanol as well as xylitol as by-products. The fatty acid profile of L. starkeyi was remarkably similar to that of palm oil, one of the most common vegetable oil feedstock used in biodiesel production with oleic acid as the major fatty acid followed by palmitic, stearic and linoleic acids.

    2019年01月, Journal of bioscience and bioengineering, 127 (6), 726 - 731, 英語, 国内誌

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    研究論文(学術雑誌)

  • Ario Betha Juanssilfero, Prihardi Kahar, Rezky Lastinov Amza, Nao Miyamoto, Hiromi Otsuka, Hana Matsumoto, Chie Kihira, Ahmad Thontowi, Yopi, Chiaki Ogino, Bambang Prasetya, Akihiko Kondo

    A two-stage selection process was applied to eight oleaginous yeast strains from the Lipomyces genera. In the primary selection stage, a nitrogen-limited mineral medium (-NMM) that contained a mixture of glucose and xylose as a carbon source was used to evaluate the lipid-accumulating abilities of the yeast strains. The strains L. doorenjongii, L. orientalis, and L. starkeyi were selected as the potential strains in the primary selection. These three strains exhibited a remarkable ability to simultaneously assimilate glucose and xylose and achieved a cell biomass of more than 30 g/L. The values for lipid content in the selected strains were 57.89 ± 1.92, 56.38 ± 1.93, and 77.14 ± 1.55% for L. doorenjongii, L. orientalis, and L. starkeyi, respectively. In the secondary selection, when the -NMM medium contained an inhibitory chemical compound (ICC), the selected strains showed a different tolerance level against each of the typical inhibitor compounds. However, L. starkeyi accumulated the highest lipid content and yield at 68.24 ± 2.48% and 0.19 ± 0.00 (w/w), respectively. L. starkeyi accumulated high levels of intracellular lipid and tolerated the ICC. The composition of fatty acid methyl esters (FAMEs) was unaltered by the presence of ICC and the major FAMEs consisted of oleic, palmitic, stearic, palmitoleic and linoleic acids.

    Elsevier B.V., 2018年09月15日, Biochemical Engineering Journal, 137, 182 - 191, 英語

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    研究論文(学術雑誌)

  • Wijaya H, Sasaki K, Kahar P, Yopi, Kawaguchi H, Sazuka T, Ogino C, Prasetya B, Kondo A

    The aim of this study was to construct a cost-effective method for repeated bioethanol production using membrane (ultrafiltration permeation and nanofiltration concentration)-concentrated sweet sorghum juice by using flocculent Saccharomyces cerevisiae F118 strain. With low initial dry cell concentrations at around 0.28-0.35 g L-1, the S. cerevisiae F118 strain provided an ethanol titer of 86.19 ± 1.15 g L-1 (theoretical ethanol yield of 70.77%), which was higher than the non-flocculent S. cerevisiae BY4741 strain at 33.92 ± 0.99 g L-1 after 24 h fermentation. This result was correlated with higher gene expressions of the sucrose-hydrolysing enzyme invertase, sugar phosphorylation, and pyruvate-to-ethanol pathways in the F118 strain compared with the BY4741 strain. Sequential fed-batch fermentation was conducted, and the F118 strain was easily separated from the fermentation broth via the formation of flocs and sediment. After the 5th cycle of fermentation with the F118 strain, the ethanol concentration reached 100.37 g L-1.

    2018年07月, Bioresource technology, 265, 542 - 547, 英語, 国際誌

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    研究論文(学術雑誌)

  • Takenaka M, Lee JM, Kahar P, Ogino C, Kondo A

    Actinobacteria plays a key role in the cycling of organic matter in soils. They secret biomass-degrading enzymes that allow it to produce the unique metabolites that originate in plant biomass. Although past studies have focused on these unique metabolites, a large-scale screening of Actinobacteria is yet to be reported to focus on their biomass-degrading ability. In the present study, a rapid and simple method is constructed for a large-scale screening, and the novel resources that form the plant biomass-degrading enzyme cocktail are identified from 850 isolates of Actinobacteria. As a result, Nonomuraea fastidiosa secretes a biomass degrading enzyme cocktail with the highest enzyme titer, although cellulase activities are lower than a commercially available enzyme. So the rich accessory enzymes are suggested to contribute to the high enzyme titer for a pretreated bagasse with a synergistic effect. Additionally, an optimized cultivation method of biomass induction caused to produce the improved enzyme cocktail indicated strong enzyme titers and a strong synergistic effect. Therefore, the novel enzyme cocktails are selected via the optimized method for large-scale screening, and then the enzyme cocktail can be improved via the optimized production with biomass-induction.

    2018年07月, Biotechnology journal, 14 (3), e1700744, 英語, 国際誌

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    研究論文(学術雑誌)

  • Ario B. Juanssilfero, Prihardi Kahar, Rezky L. Amza, Nao Miyamoto, Hiromi Otsuka, Hana Matsumoto, Chie Kihira, Ahmad Thontowi, Yopi, Chiaki Ogino, Bambang Prasetya, Akihiko Kondo

    Oleaginous microbes can convert substrates such as carbon dioxide, sugars, and organic acids to single-cell oils (SCOs). Among the oleaginous microorganisms, Lipomyces starkeyi is a particularly well-suited host given its impressive native abilities, including the capability to utilize a wide variety of carbon sources. In this work, the potential of L. starkeyi NBRC10381 to produce SCOs in a synthetically nitrogen-limited mineral medium (-NMM) was investigated by differing the inoculum size using glucose and/or xylose as a carbon source. Fermentation using glucose and xylose as mixed carbon sources generated the highest production of biomass at 40.8 g/L, and achieved a lipid content of 84.9% (w/w). When either glucose or xylose was used separately, the totals for achieved lipid content were 79.6% (w/w) and 85.1% (w/w), respectively. However, biomass production was higher for glucose than for xylose (30.3 vs. 28.7 g/L, respectively). This study describes the first simultaneous achievement of higher levels of cell mass and lipid production using glucose and/or xylose as the carbon sources in different inoculum sizes.

    Elsevier B.V., 2018年06月01日, Journal of Bioscience and Bioengineering, 125 (6), 695 - 702, 英語

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    研究論文(学術雑誌)

  • Nanik Rahmani, Prihardi Kahar, Puspita Lisdiyanti, Euis Hermiati, Jaemin Lee, Yopi, Bambang Prasetya, Chiaki Ogino, Akihiko Kondo

    The addition of enzymes that are capable of degrading hemicellulose has a potential to reduce the need for commercial enzymes during biomass hydrolysis in the production of fermentable sugars. In this study, a high xylanase producing actinomycete strain (Kitasatospora sp. ID06-480) and the first ethyl ferulate producing actinomycete strain (Nonomuraea sp. ID06-094) were selected from 797 rare actinomycetes, respectively, which were isolated in Indonesia. The addition (30%, v/v) of a crude enzyme supernatant from the selected strains in sugarcane bagasse hydrolysis with low-level loading (1 FPU/g-biomass) of Cellic® CTec2 enhanced both the released amount of glucose and reducing sugars. When the reaction with Ctec2 was combined with crude enzymes containing either xylanase or feruloyl esterase, high conversion yield of glucose from cellulose at 60.5% could be achieved after 72 h-saccharification.

    Japan Society for Bioscience Biotechnology and Agrochemistry, 2018年, Bioscience, Biotechnology and Biochemistry, 82 (5), 904 - 915, 英語

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    研究論文(学術雑誌)

  • Alex Prima, Kiyotaka Y. Hara, Apridah Cameliawati Djohan, Norimasa Kashiwagi, Prihardi Kahar, Jun Ishii, Hideki Nakayama, Fumiyoshi Okazaki, Bambang Prasetya, Akihiko Kondo, Yopi, Chiaki Ogino

    This work aims to produce glutathione directly from mannan-based bioresources using engineered Saccharomyces cerevisiae. Mannan proved to be a valuable carbon source for glutathione production by this organism. Mannan-hydrolyzing S. cerevisiae was developed by heterologous expression of mannanase/ mannosidase on its cell surface. This strain efficiently produced glutathione from mannose polysaccharide, beta-1,4-mannan. Furthermore, it produced glutathione from locust bean gum (LBG), a highly dense and inexpensive mannan-based bioresource, as sole carbon source. Glutathione productivity from LBG was enhanced by engineering the glutathione metabolism of mannan-hydrolyzing S. cerevisiae. Expression of extracellular mannanase/mannosidase protein combined with intracellular metabolic engineering is potentially applicable to the efficient, environmentally friendly bioproduction of targeted products from mannan-based bioresources. (C) 2017 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2017年12月, BIORESOURCE TECHNOLOGY, 245 (Pt B), 1400 - 1406, 英語

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    研究論文(学術雑誌)

  • Prihardi Kahar, Eny Ida Riyanti, Hiromi Otsuka, Hana Matsumoto, Chie Kihira, Chiaki Ogino, Akihiko Kondo

    This study provides insight observation based on the gene expression and the metabolomic analysis of the natural robust yeast Saccharomyces cerevisiae NBRC849 during the fermentation in the medium containing inhibitory chemical complexes (ICC) at different concentrations. The tolerance mechanisms involved in the strain might have existed through the upregulation of genes involved in NAD(H)/NADP (H) cofactors generations (ALD6, ZWF1, GND1), membrane robustness for efflux pump (YOR1, PDR5, TPO3) and cation/polyamine transport (TPO3). The alteration of metabolic flux to the shikimic pathway was also found in this strain, resulted in the enhanced formation of aromatic amino acid required for cell survival. Enhanced expression of these genes as well as the increase of metabolic flux to shikimic pathway were suggested to result in the robustness of non-flocculating S. cerevisiae haploid strain. (C) 2017 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2017年12月, BIORESOURCE TECHNOLOGY, 245 (Pt B), 1436 - 1446, 英語

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    研究論文(学術雑誌)

  • Hideo Kawaguchi, Yohei Katsuyama, Du Danyao, Prihardi Kahar, Sachiko Nakamura-Tsuruta, Hiroshi Teramura, Keiko Wakai, Kumiko Yoshihara, Hiromichi Minami, Chiaki Ogino, Yasuo Ohnishi, Ahikiko Kondo

    Caffeic acid (3,4-dihydroxycinnamic acid) serves as a building block for thermoplastics and a precursor for biologically active compounds and was recently produced from glucose by microbial fermentation. To produce caffeic acid from inedible cellulose, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) reactions were compared using kraft pulp as lignocellulosic feedstock. Here, a tyrosine-overproducing Escherichia coli strain was metabolically engineered to produce caffeic acid from glucose by introducing the genes encoding a 4-hydroxyphenyllactate 3-hydroxylase (hpaBC) from Pseudomonas aeruginosa and tyrosine ammonia lyase (fevV) from Streptomyces sp. WK-5344. Using the resulting recombinant strain, the maximum yield of caffeic acid in SSF (233 mg/L) far exceeded that by SHF (37.9 mg/L). In the SSF with low cellulase loads (ae<currency>2.5 filter paper unit/g glucan), caffeic acid production was markedly increased, while almost no glucose accumulation was detected, indicating that the E. coli cells experienced glucose limitation in this culture condition. Caffeic acid yield was also negatively correlated with the glucose concentration in the fermentation medium. In SHF, the formation of by-product acetate and the accumulation of potential fermentation inhibitors increased significantly with kraft pulp hydrolysate than filter paper hydrolysate. The combination of these inhibitors had synergistic effects on caffeic acid fermentation at low concentrations. With lower loads of cellulase in SSF, less potential fermentation inhibitors (furfural, 5-hydroxymethyfurfural, and 4-hydroxylbenzoic acid) accumulated in the medium. These observations suggest that glucose limitation in SSF is crucial for improving caffeic acid yield, owing to reduced by-product formation and fermentation inhibitor accumulation.

    SPRINGER, 2017年07月, APPLIED MICROBIOLOGY AND BIOTECHNOLOGY, 101 (13), 5279 - 5290, 英語

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    研究論文(学術雑誌)

  • Rahmani N, Kashiwagi N, Lee J, Niimi-Nakamura S, Matsumoto H, Kahar P, Lisdiyanti P, Yopi, Prasetya B, Ogino C, Kondo A

    Mannan endo-1,4-beta-mannosidase(commonly known as beta-mannanase) catalyzes a random cleavage of the beta-D-1,4mannopyranosyl linkage in mannan polymers. The enzyme has been utilized in biofuel production from lignocellulose biomass, as well as in production of mannooligosaccharides (MOS) for applications in feed and food industries. We aimed to obtain a beta-mannanase, for such mannan polymer utilization, from actinomycetes strains isolated in Indonesia. Strains exhibiting high mannanase activity were screened, and one strain belonging to the genus Kitasatospora was selected. We obtained a beta-mannanase from this strain, and an amino acid sequence of this Kitasatospora beta-mannanase showed a 58-71% similarity with the amino acid sequences of Streptomyces beta-mannanases. The Kitasatospora beta-mannanase showed a significant level of activity (944 U/mg) against locust bean gum (0.5% w/v) and a potential for oligosaccharide production from various mannan polymers. The beta-mannanase might be beneficial particularly in the enzymatic production of MOS for applications of mannan utilization.

    BIOMED CENTRAL LTD, 2017年05月, AMB Express, 7 (1), 100, 英語

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    研究論文(学術雑誌)

  • Han-Hsiu Hsu, Michihiro Araki, Masao Mochizuki, Yoshimi Hori, Masahiro Murata, Prihardi Kahar, Takanobu Yoshida, Tomohisa Hasunuma, Akihiko Kondo

    Chinese hamster ovary (CHO) cells are the primary host used for biopharmaceutical protein production. The engineering of CHO cells to produce higher amounts of biopharmaceuticals has been highly dependent on empirical approaches, but recent high-throughput "omics" methods are changing the situation in a rational manner. Omics data analyses using gene expression or metabolite profiling make it possible to identify key genes and metabolites in antibody production. Systematic omics approaches using different types of time-series data are expected to further enhance understanding of cellular behaviours and molecular networks for rational design of CHO cells. This study developed a systematic method for obtaining and analysing time-dependent intracellular and extracellular metabolite profiles, RNA-seq data (enzymatic mRNA levels) and cell counts from CHO cell cultures to capture an overall view of the CHO central metabolic pathway (CMP). We then calculated correlation coefficients among all the profiles and visualised the whole CMP by heatmap analysis and metabolic pathway mapping, to classify genes and metabolites together. This approach provides an efficient platform to identify key genes and metabolites in CHO cell culture.

    NATURE PUBLISHING GROUP, 2017年03月, SCIENTIFIC REPORTS, 7, 43518, 英語

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    研究論文(学術雑誌)

  • Ishii J, Okazaki F, Djohan AC, Hara KY, Asai-Nakashima N, Teramura H, Andriani A, Tominaga M, Wakai S, Kahar P, Yopi, Prasetya B, Ogino C, Kondo A

    Background: Mannans represent the largest hemicellulosic fraction in softwoods and also serve as carbohydrate stores in various plants. However, the utilization of mannans as sustainable resources has been less advanced in sustainable biofuel development. Based on a yeast cell surface-display technology that enables the immobilization of multiple enzymes on the yeast cell walls, we constructed a recombinant Saccharomyces cerevisiae strain that co-displays beta-mannanase and beta-mannosidase; this strain is expected to facilitate ethanol fermentation using mannan as a biomass source. Results: Parental yeast S. cerevisiae assimilated mannose and glucose as monomeric sugars, producing ethanol from mannose. We constructed yeast strains that express tethered beta-mannanase and beta-mannosidase; co-display of the two enzymes on the cell surface was confirmed by immunofluorescence staining and enzyme activity assays. The constructed yeast cells successfully hydrolyzed 1,4-beta-D-mannan and produced ethanol by assimilating the resulting mannose without external addition of enzymes. Furthermore, the constructed strain produced ethanol from 1,4-beta-D-mannan continually during the third batch of repeated fermentation. Additionally, the constructed strain produced ethanol from ivory nut mannan; ethanol yield was improved by NaOH pretreatment of the substrate. Conclusions: We successfully displayed beta-mannanase and beta-mannosidase on the yeast cell surface. Our results clearly demonstrate the utility of the strain co-displaying beta-mannanase and beta-mannosidase for ethanol fermentation from mannan biomass. Thus, co-tethering beta-mannanase and beta-mannosidase on the yeast cell surface provides a powerful platform technology for yeast fermentation toward the production of bioethanol and other biochemicals from lignocellulosic materials containing mannan components.

    BIOMED CENTRAL LTD, 2016年09月, Biotechnology for biofuels, 9 (1), 188, 英語

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    研究論文(学術雑誌)

  • Hideo Kawaguchi, Hiroshi Teramura, Kouji Uematsu, Kiyotaka Y. Hara, Tomohisa Hasunuma, Ko Hirano, Takashi Sazuka, Hidemi Kitano, Yota Tsuge, Prihardi Kahar, Satoko Niimi-Nakamura, Ken-Ichi Oinuma, Naoki Takaya, Shigemitsu Kasuga, Chiaki Ogino, Akihiko Kondo

    Dilute acid-pretreated sorghum bagasse, which was predominantly composed of glucan (59%) and xylose (7.2%), was used as a lignocellulosic feedstock for D-phenyllactic acid (PhLA) production by a recombinant Escherichia coli strain expressing phenylpyruvate reductase from Wickerhamia fluorescens. During fermentation with enzymatic hydrolysate of sorghum bagasse as a carbon source, the PhLA yield was reduced by 35% compared to filter paper hydrolysate, and metabolomics analysis revealed that NAD(P)H regeneration and intracellular levels of erythrose-4-phosphate and phosphoenolpyruvate for PhLA biosynthesis markedly reduced. Compared to separate hydrolysis and fermentation (SHF) with sorghum bagasse hydrolysate, simultaneous saccharification and fermentation (SSF) of sorghum bagasse under glucose limitation conditions yielded 4.8-fold more PhLA with less accumulation of eluted components, including p-coumaric acid and aldehydes, which inhibited PhLA fermentation. These results suggest that gradual enzymatic hydrolysis during SSF enhances PhLA production under glucose limitation and reduces the accumulation of fermentation inhibitors, collectively leading to increased PhLA yield. (c) 2015 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2015年04月, BIORESOURCE TECHNOLOGY, 182, 169 - 178, 英語

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    研究論文(学術雑誌)

  • PRIHARDI KAHAR, SHUZO TANAKA

    Bioethanol production from lignocellulosic biomass, in particular xylose, is currently of great concern, given the abundance of this sugar in the world, because Saccharomyces cerevisiae, which is widely used for bioethanol production, is unable to naturally ferment xylose. The aim of this study was to obtain a novel yeast capable of stably producing ethanol from biomass contain

    Springer, 2014年, Sustainable Chemical Processes, 2 (17), 1 - 12, 英語

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    研究論文(学術雑誌)

  • Prihardi Kahar, Kazuo Taku, Shuzo Tanaka

    The multiple effects of pretreatments by chemical delignification using acidified sodium chlorite (ASC) and swelling using sodium bicarbonate (SB) for enzymatic saccharification of rice straw in bioethanol production have been investigated in this study. The treatment with the combination of ASC three times (3 x ASC) first and SB later resulted in the significant reduction in Mason lignin content up to 90% (wt./wt.). By the saccharification of the pretreated rice straw with cellulase enzymes, it was confirmed that SB treatment was an important step in the pretreatment process not only to disintegrate the cellulose structure but also to facilitate the amorphization of the crystalline cellulose as well as the extended removal of integrated lignin. Furthermore, FTIR analyses revealed that the crystal type of cellulose appeared to be changed from type I to type II by SB treatment, thereby increasing the cellulose surface area and making it more accessible to the cellulase enzyme. Conversion rate to sugar was remarkably increased when 3x ASC + SB treatments were applied to untreated rice straw, even though the saccharification of the treated rice straw was performed at a low enzyme loading (1/100, wt.-enzymes/wt.-substrate). Conclusively, rice straw could be saccharified at high yield in short time at low cellulase loading, enables the enzymatic saccharification to be more feasible for practical bioethanol production using rice straw as a substrate. (C) 2013, The Society for Biotechnology, Japan. All rights reserved.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2013年12月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 116 (6), 725 - 733, 英語

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    研究論文(学術雑誌)

  • Prihardi Kahar, Kazuo Taku, Shuzo Tanaka

    Chemical mutation of Saccharomyces cerevisiae using ethyl methane sulfonate was performed to enhance its ability of xylose uptake for ethanol production from lignocellulose under microaerobic condition. Among the appeared mutants, the mutant no. 2 (M2) strain screened using inhibitory effects of 2-deoxyglucose (DOG) showed more than 4-fold high ability in xylose uptake compared with the wild type strain, under the presence of glucose. The catabolite repression by glucose was sufficiently reduced in M2 strain due to its tolerance to the high concentration of DOG (0.5%, wt./vol.). Metabolomic analyses of various sugars in the cell revealed that some of xylose was reduced to xylitol in M2 cell, providing the concentration gradient of xylose and more uptake of xylose. Xylulose-5-phosphate was significantly detected in the crude cell extract from M2 strain, indicating higher metabolic activity in pentose phosphate pathway. This was also confirmed by in vitro analyses of key enzymes involved in glucose and xylose metabolism, such as hexokinase, glucose-6-phosphate dehydrogenase and xylose reductase. Glucose uptake was moderately suppressed in the presence of trehalose-6-phosphate inhibiting the activation of hexokinase, resulting in more uptake of xylose through hexose transport system. To our knowledge, this study is the first report verifying that the mutation technique successfully enhances the xylose uptake by S. cerevisiae, particularly under the presence of glucose. (C) 2010, The Society for Biotechnology, Japan. All rights reserved.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2011年05月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 111 (5), 557 - 563, 英語

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    研究論文(学術雑誌)

  • Febriani, Rukman Hertadi, Prihardi Kahar, Akhmaloka, Fida Madayanti

    A local thermophilic microorganism namely DMS-3 has been identified as thermostable alkaline lipase producing isolate. The bacterium was isolated from Domas hot spring, Tangkuban Perahu Mount, West Java. Based on gram staining test and Scanning Electron Microscopy, the microorganism showed a rod shape and a gram positive bacterium. The isolated showed maximum expression of lipase at pH 9 and 70°C. The lipase produced by DMS-3 isolate was purified using column chromatography of DEAE sepharose fast flow and Sephacryl S-200. Following Sephacryl separation the enzyme still showed specific activity at 54 times higher compared to that the wild type, with yield was about 4.89%. Polyacryamide gel electrophoresis combining with zymogram analysis showed that there were 4 bands of protein exhibiting lipase activity. Further analysis by eluting of each band showed that the first, second, and third band revealed few bands similar of each other on denatured SDS-PAGE. Meanwhile the fourth band only showed single band. The data suggested that DMS-3 isolated expressed more than one type of lipases.

    2010年12月01日, Biosciences Biotechnology Research Asia, 7, 617 - 622

  • Jumiarti Agus, Prihardi Kahar, Manami Hyakutake, Satoshi Tomizawa, Hideki Abe, Takeharu Tsuge, Yasuharu Satoh, Kenji Tajima

    This study aimed to investigate the factors affecting molecular weight of poly[(R)-3-hydroxybutyrate] [P(3HB)] when polyhydroxyalkanoate (PHA) synthase (PhaRC(Bsp)) from Bacillus sp. INT005 was used for P(3HB) synthesis in Escherichia coli JM109. It was found that the molecular weight of P(3HB) decreased with time in mid- and late-phase of culture and was strongly affected by culture temperature. At 37 degrees C culture temperature, the molecular weight of P(3HB) rapidly decreased from 4.4 x 10(5) to 4.8 x 10(4) with culture time, whereas it was almost unchanged at 25 degrees C. Kinetic analysis suggested that the decrease in molecular weight of P(3HB) was due to random scission of the polymer chain. The decrease in molecular weight of P(3HB) was not observed when PHA synthases other than PhaRC(Bsp) were expressed. This study sheds light on the unique behaviour in molecular weight change of P(3HB) that is synthesized by E. coli expressing PhaRCB(sp). (C) 2010 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2010年12月, POLYMER DEGRADATION AND STABILITY, 95 (12), 2250 - 2254, 英語

    研究論文(学術雑誌)

  • P. Kahar, S. Tanaka

    ELSEVIER SCIENCE BV, 2010年11月, JOURNAL OF BIOTECHNOLOGY, 150, S136 - S137, 英語

  • Prihardi Kahar, Kazuo Taku, Shuzo Tanaka

    In this study, the effect and the optimum pretreatment condition of corncobs using low strength of H(2)SO(4) were investigated, in which H(2)SO(4) was used to improve the enzymatic digestibility of corncobs for saccharification without degradation of sugars released. The optimum pretreatment condition was found to be the addition of 0.5% (vol./vol.) H(2)SO(4) and autoclaving at 122 degrees C for 20 min. Under this condition, the structural integrity of corncob was altered to make cellulose microfibrils more accessible for cellulase enzymes, and the enzymatic digestion of corncobs could be significantly enhanced. A high yield of sugar, 80% (wt./wt.), could be obtained at a low enzyme dosage of 0.024 g enzymes/g cobs, when pretreated. As a result, the ethanol production was obviously improved by the pretreatment, i.e., the ethanol yield of 77% (wt./wt.) was obtained within 36 h in the SSF fermentation using Saccharomyces cerevisiae NBRC2114. (C) 2010, The Society for Biotechnology, Japan. All rights reserved.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2010年10月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 110 (4), 453 - 458, 英語

    [査読有り]

    研究論文(学術雑誌)

  • On the swiveling motion of helices of c-subunit in rotation of ATP synthase

    Prihardi Kahar, Toshiharu Suzuki, Masasuke Yoshida

    BIOPHYSICAL SOCIETY, 2007年01月, BIOPHYSICAL JOURNAL, -, 146A - 146A, 英語

  • Takeharu Tsuge, Jumiarti Agus, Prihardi Kahar, Hideki Abe, Hideki Abe

    Polyhydroxyalkanoate (PHA) synthase (PhaC) from Wautersia eutropha was expressed in a wide range of production level in Escherichia coli XL1-Blue cells and its effects on PhaC activity, poly[(R)-3-hydroxybutyrate] [P(3HB)] production and its molecular weights were investigated. The production level of PhaC was controlled by both amount of chemical inducer (IPTG) added into the medium and use of different copy number of plasmids. In a flask experiment, as increasing PhaC production level in the cells, the PhaC activity also increased in the range of low PhaC concentration. However, PhaC activity did not further increase in the range of high PhaC concentration, probably due to formation of inclusion body in the cells. The molecular weight of P(3HB) was found to decrease with increasing PhaC activity. This trend was also verified in high cell density cultivation using 10-l jar fermentor. Furthermore, we demonstrated that use of low copy number plasmid and appropriate induction of PhaC expression were effective in achieving both high productivity and high molecular weight of P(3HB).

    2006年10月19日, Polymer Preprints, Japan, 55, 2204

  • J Agus, P Kahar, H Abe, Y Doi, T Tsuge

    Polyhydroxyalkanoate (PHA) synthase (PhaC) from Wautersia eutropha was expressed in a wide range of production level in Escherichia coli XL1-Blue cells and its effects on PhaC activity, poly [(R)-3-hydroxybutyrate] [P(3HB)] production and its molecular weights were investigated. The production level of PhaC was controlled both by the amount of chemical inducer (isopropyl-beta-D-thiogalactopyranoside, IPTG) added into the medium and the use of different copy number of plasmids. In a flask experiment, as PhaC production level in the cells increased, the PhaC activity also increased in the range of low PhaC concentration. However, PhaC activity did not further increase in the range of high PhaC concentration, probably due to the formation of inclusion body in the cells. The molecular weight of P(3HB) was found to decrease with increasing PhaC activity. This trend was also verified in high cell density cultivation using 10-1 jar fermentor. Furthermore, we demonstrated that the use of low copy number plasmid and appropriate induction of PhaC expression were effective in achieving both high productivity and high molecular weight of P(3HB). (c) 2006 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2006年08月, POLYMER DEGRADATION AND STABILITY, 91 (8), 1645 - 1650, 英語

    研究論文(学術雑誌)

  • J Agus, P Kahar, H Abe, Y Doi, T Tsuge

    This study investigated the relationship of growth conditions, host strains and molecular weights of poly[(R)-3-hydroxybutyrate] [P(3HB)] synthesized by genetically engineered Escherichia coli. Various PHA synthases belonging to types I-IV enzymes were expressed in E. coli JM109 under the same experimental conditions, and the molecular weights of the polymers were characterized by gel permeation chromatography. The results demonstrate that P(3HB) polymers have varied molecular weights and polydispersities dependent on the characteristics of the individual PHA synthase employed. P(3HB) with high number-average molecular weights (Mn) [(1.5-4.0) X 10(6)] and narrow polydispersities (1.6-1.8) were synthesized by PHA synthases from Ralstonia eutropha (type 1), Delftia acidovorans (type 1) and Allochromatium vinosum (type 111). Contrary to these, P(3HB) with relatively low M-n [(0.17-0.79) X 10(6)] and broad polydispersities (2.2-9.0) were synthesized by PHA synthases from Aeromonas caviae (type I), Pseudomonas sp. 61-3 (type II) and Bacillus sp. INT005 (type IV). Furthermore, the molecular weights of P(3HB) synthesized under various culture conditions, in various hosts of E. coli and by mutants of PHA synthase were characterized. It was found that, in addition to culture pH [Kusaka et al. Appl Microbiol Biotechnol 1997;47:140], other variances such as culture temperature, host strain and use of mutants are effective in changing polymer molecular weight. (c) 2005 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2006年05月, POLYMER DEGRADATION AND STABILITY, 91 (5), 1138 - 1146, 英語

    研究論文(学術雑誌)

  • A crucial clue to understand the molecular rotation of c-subunit ring coupled with proton translocation through F(0) of thermophilic Bacillus PS3 ATP synthase

    P. Kahar, T. Suzuki, M. Yoshida

    ELSEVIER SCIENCE BV, 2006年, BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS, 309 - 310, 英語

  • P Kahar, J Agus, Y Kikkawa, K Taguchi, Y Doi, T Tsuge

    An inducible and highly effective production of ultra-high-molecular-weight poly[(R)-3-hydroxybutyrate] [UHMW-P(3HB)] in recombinant Escherichia coli XL1-Blue was investigated. Two expression plasmids harbouring Ralstonia eutropha P(3HB) biosynthesis genes (phaCAB(Re)) downstream of an inducible trc promoter, pTrcphaCAB(Re) and pJRDTrcphaCAB(Re) were constructed using the high copy number plasmid pTrc99a and the low copy number plasmid pJRDTrc1, respectively. These plasmids and the constitutive expression plasmid harbouring phaCAB(Re) genes (pSYL105) were individually introduced into E. coli XL1-Blue, and a comparative study for P(3HB) production from glucose using a 10-1 fermentor was carried out. The highest P(3HB) productivity (2.8 g/l h) was obtained when the recombinant harbouring pJRDTrcphaCAB(Re) was cultured with the induction of gene expression. The produced P(3HB) had extremely high weight-average molecular weights ranging from 3.5 x 10 to 5.0 x 10(6). with relatively low polydispersities of around 1.5. The molecular weights remained nearly unchanged during the course of cultivation from 12 to 54 h, suggesting that a chain-transfer reaction took place to regulate the length of polymer chains within the E. coli cells. (C) 2004 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2005年01月, POLYMER DEGRADATION AND STABILITY, 87 (1), 161 - 169, 英語

    研究論文(学術雑誌)

  • P Kahar, T Tsuge, K Taguchi, Y Doi

    High yield production of polyhydroxyalkanoates (PHAs) by Ralstonia eutropha H16 and its recombinant strain PHB(-)4/pJRDEE32d13 (a PHA-negative mutant harboring Aeromonas caviae PHA synthase gene, phaC(Ac)) from renewable inexpensive soybean oil was investigated. The PHA production by the wild-type strain H16 was achieved with a high dry cells weight (118-126 g/l) and a high poly[(R)-3-hydroxybutyrate] [P(3HB)] content per dry cells of 72-76% (w/w). A copolymer of 3HB with 5 mol% (R)-3-hydroxyhexanoate, P(3HB-co-5 mol% 3HHx), could be produced from soybean oil as a sole carbon source by the recombinant strain PHB(-)4/pJRDEE32d13 with a high dry cells weight (128-138 g/l) and a high PHA content of 71-74% (w/w). The reproducible results of PHA production in the presence of soybean oil as a sole carbon source was obtained with a high yield at a range of 0.72 to 0.76 g-PHA per g-soybean oil used. (C) 2003 Elsevier Ltd. All rights reserved.

    ELSEVIER SCI LTD, 2004年01月, POLYMER DEGRADATION AND STABILITY, 83 (1), 79 - 86, 英語

    研究論文(学術雑誌)

  • L Dwiarti, K Yamane, H Yamatani, P Kahar, M Okabe

    cis-Aconitic acid decarboxylase (CAD) was assumed to be a key enzyme in the production of itaconic acid by comparing the activity of CAD from Aspergillus terreus TN484-M1 with that of CAD from the low-itaconate yielding strain Aspergillus terreus CM85J. The constitutive CAD was purified to homogeneity from A. terreus TN484-M1 by ammonium sulfate fractionation, and column chromatography on DEAE-toyopearl, Butyl-toyopearl, and Sephacryl S200HR, and then characterized. A molecular mass of 55 kDa for the native enzyme was determined by SDS-PAGE. The enzymic activity was optimal at a pH of 6.2 and temperature of 45degreesC. The K-m value for cis-aconitic acid was determined as 2.45 mM (pH 6.2, 37degreesC). The enzyme was completely inactivated by Hg+, Cu2+, Zu(2+),p-chloromercuribenzoate, and 5,5'-dithio-bis(2-nitrobenzoate).

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2002年07月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 94 (1), 29 - 33, 英語

    [査読有り]

    研究論文(学術雑誌)

  • L Dwiarti, K Yamane, H Yamatani, P Kahar, M Okabe

    cis-Aconitic acid decarboxylase (CAD) was assumed to be a key enzyme in the production of itaconic acid by comparing the activity of CAD from Aspergillus terreus TN484-M1 with that of CAD from the low-itaconate yielding strain Aspergillus terreus CM85J. The constitutive CAD was purified to homogeneity from A. terreus TN484-M1 by ammonium sulfate fractionation, and column chromatography on DEAE-toyopearl, Butyl-toyopearl, and Sephacryl S200HR, and then characterized. A molecular mass of 55 kDa for the native enzyme was determined by SDS-PAGE. The enzymic activity was optimal at a pH of 6.2 and temperature of 45degreesC. The K-m value for cis-aconitic acid was determined as 2.45 mM (pH 6.2, 37degreesC). The enzyme was completely inactivated by Hg+, Cu2+, Zu(2+),p-chloromercuribenzoate, and 5,5'-dithio-bis(2-nitrobenzoate).

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2002年07月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 94 (1), 29 - 33, 英語

    [査読有り]

    研究論文(学術雑誌)

  • Kahar Prihardi, Kobayashi Kengo, Iwata Toshiharu, HIRAKI Jun, KOJIMA Mami, OKABE Mitsuyasu

    This paper deals with studies on ε-poly-L-lysine (ε-PL) production in an airlift bioreactor (ABR) using Streptomyces albulus S410 (S410) to minimize the production cost including the downstream processing of ε-PL. In a 5-l ABR, 30 g/l of ε-PL was produced with a power consumption of 0.3 kW/m^3, the production level being similar to that in a 5-l jar fermentor with a power consumption of 8.0 kW/m^3. Furthermore, the leakage of intracellular nucleic acid (INA)-related substances into the culture broth in the ABR was less than that in the jar fermentor. Due to the high-level power consumption (8.0 kW/m^3) in the jar fermentor, the morphology of the cells changed from the pellet to filament form due to the extensive shear stress arising from continuous agitation, thereby increasing the leakage of the INA-related substances into the culture broth. This suggested that ABR would have an advantage in the low-cost production of ε-PL over stirred tank type reactors (STR).

    公益社団法人日本生物工学会, 2002年03月, Journal of bioscience and bioengineering, 93 (3), 274 - 280, 英語

    [査読有り]

    研究論文(学術雑誌)

  • PRIHARDI KAHAR

    Epsilon-poly-L-lysine(以下ePL)は、アルカロイド生産菌の検索の過程で、Streptomyces albulusの生産するL-lysineのホモポリマー(n=25-30)として酒井らにより初めて見出されたePLは必須アミノ酸であるリジンのホモポリマーであるので安全性が高くかつカチオン含量が高いので、さらにHレタリー用品、食品添加物、化粧品、医寮晶、農薬晶、電子材料などの広範な用途が期待され、ePLの工業生産プロセスが重要になってくる。我々は、培養中のpHやグルコースの残存濃度などの培養条件を検討し、ePLの高収率生産プロセスを構築することを試みた。さらに、低コスト化に向けた高純度など一PL生産システムの構築を実現するためにエアリフト型バイオリアククーでの発酵生産を検討した。

    岐阜大学機関リポジトリ, 2002年, 農学 甲第275号, 英語

    [査読有り]

    学位論文(博士)

  • GW Huang, M Okabe, P Kahar, H Tsunekawa, Y Park

    An optimal feed rate profile of a substrate (tylosin) for a novel antibiotic, acetyl-isovaleryl tylosin (AIV) production process was investigated. In the first step of optimization, a kinetic model for production of AIV from tylosin by Streptomyces thermotolerans was established properly using the least square method, followed by the confirmation that the proposed model could be used to predict the production process of AIV from tylosin. An objective function, state equations and an inequality constraint with respect to the tylosin feeding rate profile were applied to maximize the amount of AIV produced from tylosin in a fed-batch culture. The optimized tylosin feeding rate profile was determined using a direct iterative search algorithm based on the modified complex method. The simulation of AIV production at the optimal tylosin feeding profile indicates that the final amount of AIV is expected to be about 30% higher than that at the conventional constant tylosin feeding rate, which was also confirmed experimentally using a 30-l jar fermentor.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2001年05月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 91 (5), 504 - 508, 英語

    研究論文(学術雑誌)

  • P Kahar, T Iwata, J Hiraki, EY Park, M Okabe

    The enhancement of epsilon -poly-L-lysine (epsilon -PL) production by Streptomyces albulus strain no. 410 (S410) by means of a pH control strategy was investigated. S140 cells produce epsilon -PL at a high concentration if the culture pH remains at about 4.0; however, if it shifts to higher than 4.0, the accumulated epsilon -PL is depolymerized. We therefore suggest a pH control strategy for cell growth and epsilon -PL production aimed at increasing the amount of epsilon -PL produced. The cultivation was divided into two control phases. In phase I, cell growth was accelerated by maintaining the pH at higher than 5.0; in phase II, epsilon -PL production was increased by maintaining the pH at about 4.0. To avoid an increase in the pH during phase II as a result of glucose depletion, the glucose concentration was kept at around 10 g/l by glucose feeding. This control strategy enhanced the production of h-PL to 48.3 g/l from 5.7 g/l in the case of batch culture.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2001年02月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 91 (2), 190 - 194, 英語

    研究論文(学術雑誌)

  • P Kahar, T Iwata, J Hiraki, EY Park, M Okabe

    The enhancement of epsilon -poly-L-lysine (epsilon -PL) production by Streptomyces albulus strain no. 410 (S410) by means of a pH control strategy was investigated. S140 cells produce epsilon -PL at a high concentration if the culture pH remains at about 4.0; however, if it shifts to higher than 4.0, the accumulated epsilon -PL is depolymerized. We therefore suggest a pH control strategy for cell growth and epsilon -PL production aimed at increasing the amount of epsilon -PL produced. The cultivation was divided into two control phases. In phase I, cell growth was accelerated by maintaining the pH at higher than 5.0; in phase II, epsilon -PL production was increased by maintaining the pH at about 4.0. To avoid an increase in the pH during phase II as a result of glucose depletion, the glucose concentration was kept at around 10 g/l by glucose feeding. This control strategy enhanced the production of h-PL to 48.3 g/l from 5.7 g/l in the case of batch culture.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 2001年02月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 91 (2), 190 - 194, 英語

    [査読有り]

    研究論文(学術雑誌)

  • S Jia, GB Chen, P Kahar, DB Choi, M Okabe

    Corn starch and soybean oil are suitable carbon sources for the production of tetracycline by Streptomyces aureofacience CG-1. However, it could not produce more than 6 g/l of tetracycline even if initial corn starch concentration was increased to more than 100 g/l. It was confirmed by shaking flask experiments that the k(L)a in a mixture of 2% soybean oh in water was four folds compared with that without soybean oil. With the addition of soybean oil to the starch medium in a shaking flask, tetracycline production was significantly improved. By scaling-up to a 5.5-l airlift bioreactor from 500-ml Erlenmeyer flask, more than 10 g/l of tetracycline was produced with the addition of 60 g/l of soybean oil to the medium containing 100 g/l of corn starch. The dissolved oxygen level in the airlift bioreactor containing soybean oil was higher than that without soybean oil. This suggests that soybean oil is not only a suitable carbon source but is also a surface-active agent which may accelerate the oxygen transfer. This may lead to the possibility of the enhanced production of tetracycline at a low cost in airlift bioreactor.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 1999年06月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 87 (6), 825 - 827, 英語

    研究論文(学術雑誌)

  • EY Park, M Ichida, P Kahar, M Okabe

    A simple kinetics of soybean on consumption and cephamycin C production in Streptomyces sp. culture using a mineral support is proposed in this study. The mineral support was used for both suspending the soybean oil as fine oil droplets and immobilizing mycelia. The optimum concentrations of oil and mineral support for obtaining the maximum cephamycin C production were determined to be 50 and 15 g/l, respectively, by the proposed kinetics. At the optimal concentrations, the concentration of cephamycin C estimated from the proposed model and from the experimental data was 2.82 and 2.80 g/l respectively.,The results of the simulation coincided well with the experimental data for various concentrations of the soybean oil and the support. This demonstrates that our model can explain the kinetics of a culture using vegetable oil-as the carbon source and mineral support for both oil suspension and mycelial immobilization.

    SOC BIOSCIENCE BIOENGINEERING JAPAN, 1999年03月, JOURNAL OF BIOSCIENCE AND BIOENGINEERING, 87 (3), 390 - 393, 英語

    研究論文(学術雑誌)

  • S Jia, MX Wang, P Kahar, Y Park, M Okabe

    The effect of an oxygen vector on the oxygen transfer rate in air-lift bioreactor was evaluated using the ratio of the volumetric oxygen transfer coefficient to the volumetric fraction of the oxygen vector. When n-dodecane and perfluorocarbon were added at final concentrations of 3% and 2% (v/v), respectively, the oxygen transfer rate reached a maximum value. By addition of 3% (v/v) of n-dodecane to the yeast fermentation, the yeast concentration increased to 26.2 g/l which was 20% higher than in the case of fermentation in the absence of the oxygen vector.

    SOC FERMENTATION BIOENGINEERING, JAPAN, 1997年, JOURNAL OF FERMENTATION AND BIOENGINEERING, 84 (2), 176 - 178, 英語

    研究論文(学術雑誌)

  • Prihardi Kahar, Akiho Itomi, Hikari Tsuboi, Miki Ishizaki, Misa Yasuda, Chie Kihira, Hiromi Otsuka, Nurlina Binti Azmi, Hana Matsumoto, Chiaki Ogino, Akihiko Kondo

    When lignocellulosic biomass is utilized as a fermentative substrate to produce biochemicals, the existence of a yeast strain resistant to inhibitory chemical compounds (ICCs) released from the biomass becomes critical. To achieve the purpose, in this study, Saccharomyces yeast strains from a NBRC yeast culture collection were used for exploration and evaluated in two different media containing ICCs that mimic one another but resemble the hydrolysate of real biomass. Among them, S. cerevisiae F118 strain shows robustness upon the fermentation with unique flocculation trait that was strongly responsive to ICC stress. When this strain was cultured in the presence of ICCs, its cell wall hydrophobicity increased dramatically, and reduced significantly when the ICCs were depleted, demonstrating that cell-surface hydrophobicity can also act as an adaptive response to the ICCs. Cells from the strain with the highest cell-wall hydrophobicity displayed progressively stronger flocculation, indicating that the F118 strain is having unique robustness under ICC stress. Gene expression perturbation analysis revealed that mot3 gene encoding regulatory Mot3p from the F118 strain was expressed in response to the concentration of ICCs. This gene was found to control expression of ygp1 gene that encoding Ygp1p, one of cell wall proteins. Deep sequencing analysis revealed that the Mot3p of the F118 strain features a unique insertion and deletion of nucleotides that encode glutamine or asparagine residues, particularly in N-terminal domain, as determined by comparison to the Mot3p sequence from the S288c strain, which was employed as a control strain. Furthermore, the cell wall hydrophobicity of the S288c strain was greatly enhanced and became ICC-responsive after gene swapping with the mot3 gene from the F118 strain. The gene-swapped S288c strain fermented 6-fold faster than the wild-type strain, producing 14.5 g/L of ethanol from 30 g/L of glucose consumed within 24 h in a medium containing the ICCs. These such modifications to Mot3p in unique locations in its sequence have a potential to change the expression of a gene involved in cell wall hydrophobicity and boosted the flocculation response to ICC stress, allowing for the acquisition of extraordinary robustness.

    2022年03月04日, Metabolic engineering, 72, 82 - 96, 英語, 国際誌

    [査読有り]

    研究論文(学術雑誌)

MISC

  • Jun Ishii, Fumiyoshi Okazaki, Apridah Cameliawati Djohan, Kiyotaka Y. Hara, Nanami Asai-Nakashima, Hiroshi Teramura, Ade Andriani, Masahiro Tominaga, Satoshi Wakai, Prihardi Kahar, Yopi, Bambang Prasetya, Chiaki Ogino, Akihiko Kondo

    Background: Mannans represent the largest hemicellulosic fraction in softwoods and also serve as carbohydrate stores in various plants. However, the utilization of mannans as sustainable resources has been less advanced in sustainable biofuel development. Based on a yeast cell surface-display technology that enables the immobilization of multiple enzymes on the yeast cell walls, we constructed a recombinant Saccharomyces cerevisiae strain that co-displays beta-mannanase and beta-mannosidase; this strain is expected to facilitate ethanol fermentation using mannan as a biomass source. Results: Parental yeast S. cerevisiae assimilated mannose and glucose as monomeric sugars, producing ethanol from mannose. We constructed yeast strains that express tethered beta-mannanase and beta-mannosidase; co-display of the two enzymes on the cell surface was confirmed by immunofluorescence staining and enzyme activity assays. The constructed yeast cells successfully hydrolyzed 1,4-beta-D-mannan and produced ethanol by assimilating the resulting mannose without external addition of enzymes. Furthermore, the constructed strain produced ethanol from 1,4-beta-D-mannan continually during the third batch of repeated fermentation. Additionally, the constructed strain produced ethanol from ivory nut mannan; ethanol yield was improved by NaOH pretreatment of the substrate. Conclusions: We successfully displayed beta-mannanase and beta-mannosidase on the yeast cell surface. Our results clearly demonstrate the utility of the strain co-displaying beta-mannanase and beta-mannosidase for ethanol fermentation from mannan biomass. Thus, co-tethering beta-mannanase and beta-mannosidase on the yeast cell surface provides a powerful platform technology for yeast fermentation toward the production of bioethanol and other biochemicals from lignocellulosic materials containing mannan components.

    BIOMED CENTRAL LTD, 2016年09月, BIOTECHNOLOGY FOR BIOFUELS, 9 (Sept), 9:188 (WEB ONLY), 英語

  • 凝集性酵母における新規な阻害剤耐性機構の解明

    糸見明穂, 紀平和枝, KAHAR Prihardi, 荻野千秋, 近藤昭彦

    2016年08月25日, 日本生物工学会大会講演要旨集, 68th, 316, 日本語

  • Yeast breeding for fuels and chemicals production from Indonesia Culture Collection

    KAHAR Prihardi, OTSUKA Hiromi, KIHARA Chie, ITOMI Akiho, LEE Jaemin, THONTOWI Ahmad, OCTAVIANA Senlio, JALU Filemon, KANTI Atit, YOPI, OGINO Chiaki, PRASETYA Bambang, KONDO Akihiko

    2016年03月13日, 化学工学会年会研究発表講演要旨集(CD-ROM), 81st, ROMBUNNO.N316, 英語

  • Economic Value of Current Main Use of Oil Palm Empty Fruit Bunches (EFB) and Its Potential Use for Biofuel

    SIMAMORA Manaek, OGINO Chiaki, SUNARYA Yopi, KAHAR Prihardi, PRASETYA Bambang, PRASETYA Bambang, SUBIYANTO Bambang, YAMAN Aris, MAULANA Syafrizal, MALUDIN Syafrizal, MUNAWAR Sasa Sofyan

    2016年03月13日, 化学工学会年会研究発表講演要旨集(CD-ROM), 81st, ROMBUNNO.N321, 英語

  • Biorefinery research in Kobe and Indonesia

    OGINO Chiaki, LEE JaeMin, KAHAR Prihardi, KONDO Akihiko

    2016年03月13日, 化学工学会年会研究発表講演要旨集(CD-ROM), 81st, ROMBUNNO.N302, 英語

  • Biorefinery as strategic approach for supporting of utilization of tropical lignocellulosic biomas

    PRASETYA Bambang, SUNARYA Yopi, HERMIATI Euis, THONTOWI Ahmad, HANAFI, SIMAMORA Manaek, OGINO Chiaki, KAHAR Prihardi

    2016年03月13日, 化学工学会年会研究発表講演要旨集(CD-ROM), 81st, ROMBUNNO.N313, 英語

  • マンナンバイオマスからのエタノール生産:β‐マンナナーゼとβ‐マンノシダーゼを細胞表層に提示した出芽酵母の開発

    石井純, 岡崎文美, DJOHAN Apridah Cameliawati, 原清敬, 浅井菜々実, ANDRIANI Ade, 寺村浩, KAHAR Prihardi, YOPI, PRASETYA Bambang, 荻野千秋, 近藤昭彦

    2016年03月05日, 日本農芸化学会大会講演要旨集(Web), 2016, 4A022 (WEB ONLY), 日本語

  • インドネシアの土壌から分離された放線菌由来マンナナーゼ酵素の単離と酵素活性評価

    RAHMANI Nanik, 柏木紀賢, LEE JaeMin, 中村聡子, 松本華, KAHAR Prihardi, LISDIYANTI Puspita, YOPI, PRASETYA Bambang

    2015年09月07日, 日本放線菌学会大会講演要旨集, 30th, 105, 日本語

  • 実バイオマスを微生物変換するための新しい酵母プラットフォームの探索

    KAHAR Prihardi, LEE Jaemin, 荻野千秋, 近藤昭彦

    2015年03月05日, 日本農芸化学会大会講演要旨集(Web), 2015, 3B33A01 (WEB ONLY), 日本語

  • 2P-132 Trichoderma reesei変異菌による低温性セルラーゼの産生(バイオマス,資源,エネルギー工学,一般講演)

    大久保 成章, Prihardi Kahar, 多久 和夫, 田中 修三

    公益社団法人日本生物工学会, 2013年08月25日, 日本生物工学会大会講演要旨集, 65, 日本語

  • 4Ia05 稲わらの酵素的糖化における脱リグニン処理と弛緩処理の効果(バイオマス,資源,エネルギー工学,一般講演)

    Kahar Prihardi, Taku Kazuo, Tanaka Shuzo

    公益社団法人日本生物工学会, 2012年09月25日, 日本生物工学会大会講演要旨集, 64, 英語

  • 2Aa02 バイオエタノール生産ための細胞変異融合法によるキシロース代謝利用酵母の分子育種(バイオマス・資源・エネルギー工学,一般講演)

    KAHAR Prihardi, 城間 一樹, 大久保 成章, 多久 和夫, 田中 修三

    公益社団法人日本生物工学会, 2011年08月25日, 日本生物工学会大会講演要旨集, 63, 日本語

  • 2P-1185 EMS変処理によるサカロマイセス酵母のキシロース取込能力の強化(6a生物化学工学,一般講演,生物化学工学,伝統の技と先端科学技術の融合)

    Kahar Prihardi, 多久 和夫, 田中 修三

    公益社団法人日本生物工学会, 2010年09月25日, 日本生物工学会大会講演要旨集, 22, 日本語

  • 2Ha04 未利用農業廃棄物からバイオエタノールへの効率的変換(バイオマス・資源・エネルギー工学,一般講演)

    Prihardi Kahar, 熊谷 綾華, 多久 和夫, 田中 修三

    公益社団法人日本生物工学会, 2009年08月25日, 日本生物工学会大会講演要旨集, 21, 日本語

  • 1J14-5 PHA合成酵素活性がポリ[(R)-3-ヒドロキシブタン酸]の分子量に及ぼす影響(食品科学,食品工学/有機化学,高分子化学/ペプチド工学,プロテオーム,一般講演)

    柘植 丈治, アグス ジュミアルティ, カハル プリハルディ, 阿部 英喜

    公益社団法人日本生物工学会, 2006年08月03日, 日本生物工学会大会講演要旨集, 18, 日本語

  • 2P220 Insigh into The molecular rotation of c-subunit ring in Thermophilic Bacillus PS3 ATP synthase(37. Molecular motor (II),Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)

    Kahar Prihardi, Suzuki Toshiharu, Yoshida Masasuke

    一般社団法人 日本生物物理学会, 2006年, 生物物理, 46 (2), 英語

  • 2D14-1 大豆油からのバイオポリエステル生産と環境影響評価(発酵生理学・発酵工学・培養工学,一般講演)

    柘植 丈治, カハル プリハルディ, 田口 一徳, 秋山 稔, 土肥 義治

    公益社団法人日本生物工学会, 2004年08月25日, 日本生物工学会大会講演要旨集, 16, 日本語

  • Enhancement of ε-Polylysine Production by Streptomyces albulus Strain 410 Using pH Control

    Kahar Prihardi, Iwata Toshiharu, Hiraki Jun, PARK Enoch Y, OKABE Mitsuyasu

    The enhancement of ε-poly-L-lysine (ε-PL) production by Streptomyces albulus strain no.410 (S410) by means of a pH control strategy was investigated. S140 cells produce ε-PL at a high concentration if the culture pH remains at about 4.0; however, if it shifts to higher than 4.0, the accumulated ε-PL is depolymerized. We therefore suggest a pH control strategy for cell growth and ε-PL production aimed at increasing the amount of ε-PL produced. The cultivation was divided into two control phases. In phase I, cell growth was accelerated by maintaining the pH at higher than 5.0; in phase II, ε-PL production was increased by maintaining the pH at about 4.0. To avoid an increase in the pH during phase II as a result of glucose depletion, the glucose concentration was kept at around 10 g/l by glucose feeding. This control strategy enhanced the production of ε-PL to 48.3 g/l from 5.7 g/l in the case of batch culture.

    公益社団法人日本生物工学会, 2001年02月, Journal of bioscience and bioengineering, 91 (2), 190 - 194, 英語

  • 放線菌Streptomyces therotoleransによる基質タロシンからアセチルイソバレリルタイロシン(AIV)への微生物交換プロセスにおける基質流加速度の最適化

    黄国偉, 岡部満康, カハル プリハルディ, 朴龍しゅ, 恒川博

    2000年12月01日, 日本農芸化学会誌, 74 (12), 1399, 日本語

  • 1035 抗生物質生産への大豆油の効果について

    Kahar Prihardi, 明石 和憲, Siru Jia, 朴 龍洙, 岡部 満康

    公益社団法人日本生物工学会, 1999年08月16日, 日本生物工学会大会講演要旨集, 11, 日本語

  • 1029 3-アセチル-4"-イソバレリルタイロシン(AIV)生産における動力学モデルの作成

    黄 国偉, PRIHARDI KAHAR, 朴 龍洙, 岡部 満康

    公益社団法人日本生物工学会, 1999年08月16日, 日本生物工学会大会講演要旨集, 11, 日本語

  • 1015 エアリフト型バイオリアクターでのε-ポリリジン(PL)の発酵生産に関する研究

    Kahar Prihardi, 朴 龍洙, 岡部 満康

    公益社団法人日本生物工学会, 1999年08月16日, 日本生物工学会大会講演要旨集, 11, 日本語

  • 973 pHシフトダウンモデルによるεPL高収率生産プロセスに関する研究

    Kahar Prihardi, 岩田 敏治, 平木 純, 朴 龍沫, 岡部 満康

    公益社団法人日本生物工学会, 1998年08月31日, 日本生物工学会大会講演要旨集, 10, 日本語

書籍等出版物

  • Synergistic Effects of Pretreatment Process on Enzymatic Digestion of Rice Straw for Efficient Ethanol Fermentation.

    PRIHARDI KAHAR

    その他, InTech, 2013年, 英語, In this study, the advanced pretreatment process for enzymatic hydrolysis of rice straw has been demonstrated by combining the delignification by acidified sodium chlorite with the disintegration of cellulose structure and the alteration of crystalline structure by swelling with sodium bicarbonate. The efficiency of the pretreatment process on saccharification and fermentation

    学術書

講演・口頭発表等

  • REDOXバランスにおける発酵阻害耐性酵母由来新規TDHxの影響

    Azmi Nurlina, 糸見 明穂, Kahar Prihardi, 荻野 千秋, 近藤 昭彦

    第19回化学工学会学生発表会, 2017年03月, 日本語, 化学工学会関西支部, 豊中市, 国内会議

    口頭発表(一般)

  • Development of Platform Yeast Strain Capable of Direct Fermentation of Raw Biomass to Ethanol

    Prihardi Kahar, Akiho Itomi, Ahmad Thontowi, Hiromi Otsuka, Chie Kihira, Jaemin Lee, Ario Betha Juanssil fero, Apridah Cameliawati Djohan, Yopi Sunarya, 石井 純, 荻野 千秋, Banbang Prasetya, 近藤 昭彦

    Metabolic Engineering 11, 2016年06月, 英語, Metabolic Engineering 11, 淡路市, 国際会議

    口頭発表(一般)

  • Yeast breeding for fuels and chemicals production from Indonesia Culture Collection

    KAHAR Prihardi, OTSUKA Hiromi, KIHARA Chie, ITOMI Akiho, LEE Jaemin, THONTOWI Ahmad, OCTAVIANA Senlio, JALU Filemon, KANTI Atit, YOPI, OGINO Chiaki, PRASETYA Bambang, KONDO Akihiko

    化学工学会年会研究発表講演要旨集(CD-ROM), 2016年03月13日, 英語

  • Economic Value of Current Main Use of Oil Palm Empty Fruit Bunches (EFB) and Its Potential Use for Biofuel

    SIMAMORA Manaek, OGINO Chiaki, SUNARYA Yopi, KAHAR Prihardi, PRASETYA Bambang, PRASETYA Bambang, SUBIYANTO Bambang, YAMAN Aris, MAULANA Syafrizal, MALUDIN Syafrizal, MUNAWAR Sasa Sofyan

    化学工学会年会研究発表講演要旨集(CD-ROM), 2016年03月13日, 英語

  • Biorefinery research in Kobe and Indonesia

    OGINO Chiaki, LEE JaeMin, KAHAR Prihardi, KONDO Akihiko

    化学工学会年会研究発表講演要旨集(CD-ROM), 2016年03月13日, 英語

  • Biorefinery as strategic approach for supporting of utilization of tropical lignocellulosic biomas

    PRASETYA Bambang, SUNARYA Yopi, HERMIATI Euis, THONTOWI Ahmad, HANAFI, SIMAMORA Manaek, OGINO Chiaki, KAHAR Prihardi

    化学工学会年会研究発表講演要旨集(CD-ROM), 2016年03月13日, 英語

  • マンナンバイオマスからのエタノール生産:βーマンナナーゼとβーマンノシダーゼを細胞表層に提示した出芽酵母の開発

    荻野 千秋, 石井 純, 岡崎 文美, DJHAN APRIDAH, CAMELIWATI, 原 清敬, 浅井 菜々実, ANDORIAN ADE, 寺村 浩, KAHAR PRIHARDI, YOPI, PRASETYA BAMBANG

    日本農芸化学会2016年度大会, 2016年03月, 日本語, 国内会議

    口頭発表(一般)

  • インドネシアの土壌から分離された放線菌由来マンナナーゼ酵素の単離と酵素活性評価

    RAHMANI Nanik, 柏木紀賢, LEE JaeMin, 中村聡子, 松本華, KAHAR Prihardi, LISDIYANTI Puspita, YOPI, PRASETYA Bambang

    日本放線菌学会大会講演要旨集, 2015年09月07日, 日本語

  • 実バイオマスを微生物変換するための新しい酵母プラットフォームの探索

    KAHAR Prihardi, LEE Jaemin, 荻野千秋, 近藤昭彦

    日本農芸化学会大会講演要旨集(Web), 2015年03月05日, 日本語

  • 実バイオマスを微生物変換するための新しい酵母プラットフォームの探索

    KAHAR Prihardi, 李 載みん, 荻野 千秋, 近藤 昭彦

    日本農芸化学会2015年度大会, 2015年03月, 日本語, 日本農芸化学会, 岡山市, 国内会議

    口頭発表(一般)

  • 実バイオマスからエタノール発酵するための酵母株の探索

    KAHAR Prihardi, 李載ミン, 松本華, 大塚裕美, 荻野千秋, 近藤昭彦

    日本ゲノム微生物学会年会要旨集, 2015年, 日本語

  • インドネシアを例としたバイオコンビナート構想

    荻野千秋, KAHAR Prihardi, 李載みん, 近藤昭彦

    化学工学会大会講演要旨集(CD-ROM), 2015年, 日本語

  • Trichoderma reesei変異菌による低温性セルラーゼの産生

    大久保成章, KAHAR Prihardi, 多久和夫, 田中修三

    日本生物工学会大会講演要旨集, 2013年08月25日, 日本語

  • キシロース発酵における細胞融合酵母FSC株のin vitro代謝解析

    KAHAR Prihardi, 田中修三

    日本農芸化学会大会講演要旨集(Web), 2013年03月05日, 日本語

  • Synergistic effect of delignification and alkaline swelling treatments on enzymatic degradation of rice straw

    KAHAR Prihardi, TAKU Kazuo, TANAKA Shuzo

    日本生物工学会大会講演要旨集, 2012年09月25日, 英語

  • 稲わらの並行復発酵ための高活性セルラーゼ生産

    KAHAR Prihardi, 大久保成章, 多久和夫, 田中修三

    日本農芸化学会大会講演要旨集(Web), 2012年03月05日, 日本語

  • バイオエタノール生産ための細胞変異融合法によるキシロース代謝利用酵母の分子育種

    KAHAR Prihardi, 城間一樹, 大久保成章, 多久和夫, 田中修三

    日本生物工学会大会講演要旨集, 2011年08月25日, 日本語

  • 高効率エタノール変換に向けた稲藁の脱リグニン及び弛緩処理技術の開発

    PRIHARDI Kahar, 多久和夫, 田中修三

    日本農芸化学会大会講演要旨集, 2011年03月05日, 日本語

  • EMS変処理によるサカロマイセス酵母のキシロース取込能力の強化

    PRIHARDI Kahar, 多久和夫, 田中修三

    日本生物工学会大会講演要旨集, 2010年09月25日, 日本語

  • 未利用農業廃棄物からバイオエタノールへの効率的変換

    PRIHARDI Kahar, 熊谷綾華, 多久和夫, 田中修三

    日本生物工学会大会講演要旨集, 2009年08月25日, 日本語

  • 微生物合成ポリエステルの分子量特性

    柘植丈治, 冨澤哲, AGUS Jumiarti, KAHAR Priharudi, 阿部英喜, 田口精一

    高分子学会予稿集(CD-ROM), 2007年09月04日, 日本語

  • Insigh into The molecular rotation of c-subunit ring in Thermophilic Bacillus PS3 ATP synthase

    KAHAR Prihardi, SUZUKI Toshiharu, YOSHIDA Masasuke

    生物物理, 2006年10月01日, 英語

  • 2P220 Insigh into The molecular rotation of c-subunit ring in Thermophilic Bacillus PS3 ATP synthase(37. Molecular motor (II),Poster Session,Abstract,Meeting Program of EABS & BSJ 2006)

    Kahar Prihardi, Suzuki Toshiharu, Yoshida Masasuke

    生物物理, 2006年10月01日, 英語

  • PHA合成酵素活性がポリ[(R)‐3‐ヒドロキシブタン酸]の分子量に及ぼす影響

    柘植丈治, AGUS Jumiarti, KAHAR Prihardi, 阿部英喜

    日本生物工学会大会講演要旨集, 2006年08月03日, 日本語

  • 遺伝子組換え大腸菌が合成するポリ[(R)‐3‐ヒドロキシブタン酸]の分子量

    柘植丈治, AGUS Jumiarti, KAHAR Prihardi, 阿部英喜

    高分子学会予稿集(CD-ROM), 2006年05月10日, 日本語

  • INSIGHT INTO THE MOLECULAR ROTATION OF C-SUBUNIT RING IN THERMOPHILIC BACILLUS PS3 ATP SYNTHASE

    KAHAR Prihardi, SUZUKI Toshiharu, YOSHIDA Masasuke

    生化学, 2006年, 英語

  • Molecular weight of poly[(R)-3-hydroxybutyrate] synthesized by type IV PHA synthase in Escherichia coli

    Jumiarti Agus, Jumiarti Agus, Prihardi Kahar, Prihardi Kahar, Takeharu Tsuge, Takeharu Tsuge, Yoshiharu Doi, Yoshiharu Doi

    Polymer Preprints, Japan, 2005年12月01日, In this study, we investigated the molecular weight of P(3HB) synthesized by the type IV PHA synthase from Bacillus sp. INT005 (PhaRC Bs). The PhaRC Bs preferred to synthesize low molecular weight of P(3HB) in Escherichia coli. The curve of molecular weight distribution was found to depend on cultivation time. Host strain of E. coli also affected the molecular weight of polymer, but culture temperature did not.

  • Effect of temperature on molecular weight of poly[(R)-3-hydroxybutyrate)] synthesized by Bacillus sp. INT005 PHA synthase in recombinant Escherichia coli

    AGUS Jumiarti, KAHAR Prihardi, TSUGE Takeharu, ABE Hideki, DOI Yoshiharu

    高分子学会予稿集(CD-ROM), 2005年09月05日, 英語

  • ポリ(3‐ヒドロキシブチレート)の分子量における重合酵素の発現量および酵素活性の影響

    KAHAR Prihardi, AGUS Jumiarti, 柘植丈治, 土肥義治

    高分子学会予稿集(CD-ROM), 2005年05月10日, 日本語

  • Molecular weight of poly[(R)-3-hydroxybutyrate] synthesized by type IV PHA synthase in Escherichia coli

    AGUS Jumiarti, KAHAR Prihardi, TSUGE Takeharu, DOI Yoshiharu

    高分子学会予稿集(CD-ROM), 2005年05月10日, 英語

  • 遺伝子組換え微生物を用いたポリヒドロキシアルカン酸(PHA)の効率的生合成手法の開発

    KAHAR P, AGUS J, 柘植丈治, 田口一徳, 土肥義治

    高分子学会予稿集(CD-ROM), 2004年09月01日, 日本語

  • Factors affecting the molecular weight of poly[(R)-3-hydroxybutyrate] in recombinant Escherichia coli

    AGUS J, KAHAR P, TSUGE T, DOI Y

    高分子学会予稿集(CD-ROM), 2004年09月01日, 英語

  • 大豆油からのバイオポリエステル生産と環境影響評価

    柘植丈治, KAHAR Prihardi, 田口一徳, 秋山稔, 土肥義治

    日本生物工学会大会講演要旨集, 2004年08月25日, 日本語

  • 遺伝子組換え大腸菌による超高分子量P(3HB)の効率的生産

    KAHAR P, 柘植丈治, 田口一徳, 土肥義治

    高分子学会予稿集(CD-ROM), 2004年05月10日, 日本語

  • 大豆油からのバイオポリエステル生産と環境影響評価

    TAKEHARU TSUGE, PRIHARDI KAHAR, KAZUNORI TAGUCHI, MINORU AKIYAMA, YOSHIHARU DOI

    第56回日本生物工学会大会, 2004年, 日本語, 日本生物工学会, 名城大学、名古屋市, 国内会議

    口頭発表(一般)

  • Effective Production and Kinetic Characteristic of Ultra-high-molecular-weight of PHB in Recombinant Escherichia coli.

    PRIHARDI KAHAR, TAKEHARU TSUGE, KAZUNORI TAGUCHI, YOSHIHARU DOI

    Int. Symposium on Biological Polyesters, 2004年, 英語, IUPAC, Beijing, China, 国際会議

    ポスター発表

  • バイオポリエステル微生物生産とライフサイクルインベントリ評価

    柘植丈治, KAHAR P, 秋山稔, 田口一徳, 土肥義治

    高分子学会予稿集, 2003年09月10日, 日本語

  • 大豆油を原料としたバイオポリエステルの高効率・高収率生産

    KAHAR P, 柘植丈治, 田口一徳, 土肥義治

    高分子学会予稿集, 2003年05月08日, 日本語

  • エアリフト型バイオリアクター(Airlift Bioreactor,ABR)におけるε‐ポリリジン(ε‐Polylysine,ε‐PL)の生産に関する研究

    KAHAR P, 岡部満康, 小島麻美, 小林健吾, 平木純, 岩田敏治

    日本農芸化学会大会講演要旨集, 2002年03月05日, 日本語

  • 有限要素法による気泡塔における溶存酸素分布の解析

    PRIHARDI KAHAR, 小島麻美, 岡部満康

    乳酸菌工学研究部会講演会, 2002年, 日本語, 日本生物工学会, 茨城, 国内会議

    [招待有り]

    口頭発表(招待・特別)

  • 放線菌Streptomyces therotoleransによる基質タロシンからアセチルイソバレリルタイロシン(AIV)への微生物交換プロセスにおける基質流加速度の最適化

    黄国偉, 岡部満康, カハル プリハルディ, 朴龍しゅ, 恒川博

    日本農芸化学会誌, 2000年12月01日, 日本語

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    化学工学会秋季大会研究発表講演要旨集, 2000年08月12日, 日本語

  • Production of epsilon-polylysine by Streptomyces albulus Strain.

    PRIHARDI KAHAR, ENOCH Y. PARK, MITSUYASU OKABE

    The 11th International Biotechnology Symposium, 2000年, 英語, IUPAC, Berlin, Germany, 国際会議

    ポスター発表

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    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • エアリフト型バイオリアクターでのε‐ポリリジン(PL)の発酵生産に関する研究

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    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • 3‐アセチル‐4′′‐イソバレリルタイロシン(AIV)生産における動力学モデルの成

    黄国偉, PRIHARDI K, 朴龍しゅ, 岡部満康

    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • 1035 抗生物質生産への大豆油の効果について

    Kahar Prihardi, 明石 和憲, Siru Jia, 朴 龍洙, 岡部 満康

    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • 1029 3-アセチル-4"-イソバレリルタイロシン(AIV)生産における動力学モデルの作成

    黄 国偉, PRIHARDI KAHAR, 朴 龍洙, 岡部 満康

    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • 1015 エアリフト型バイオリアクターでのε-ポリリジン(PL)の発酵生産に関する研究

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    日本生物工学会大会講演要旨集, 1999年08月16日, 日本語

  • 973 pHシフトダウンモデルによるεPL高収率生産プロセスに関する研究

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    日本生物工学会大会講演要旨集, 1998年08月31日, 日本語

  • pHシフトダウンモデルによるεPL高収率生産プロセスに関する研究

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    日本生物工学会大会講演要旨集, 1998年, 日本語

共同研究・競争的資金等の研究課題

産業財産権

  • ポリ-3-ヒドロキシアルカン酸の製造方法

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    特願2004-100098, 特開2005-278559, 2005年10月13日

    特許権