- 著者
- Kenshi Watanabe Kim Hazel V. Arafiles Risa Higashi Yoshiko Okamura Takahisa Tajima Yukihiko Matsumura Yutaka Nakashimada Keisuke Matsuyama Tsunehiro Aki
- 出版者
- Japan Oil Chemists' Society
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.67, no.5, pp.571-578, 2018 (Released:2018-05-01)
- 参考文献数
- 50
- 被引用文献数
- 12 35
The marine eukaryotic microheterotroph thraustochytrid genus Aurantiochytrium is a known producer of polyunsaturated fatty acids, carotenoids, and squalene. We previously constructed a lipid fermentation system for Aurantiochytrium sp. strains using underutilized biomass, such as canned syrup and brown macroalgae. To improve the productivity, in this study, Aurantiochytrium sp. RH-7A and RH-7A-7 that produced high levels of carotenoids, such as astaxanthin and canthaxanthin, were isolated through chemical mutagenesis. Moreover, metabolomic analysis of the strain RH-7A revealed that oxidative stress impacts carotenoid accumulation. Accordingly, the addition of ferrous ion (Fe2+), as an oxidative stress compound, to the culture medium significantly enhanced the production of astaxanthin by the mutants. These approaches improved the productivity of astaxanthin up to 9.5 mg/L/day at the flask scale using not only glucose but also fructose which is the main carbon source in fermentation systems with syrup and brown algae as the raw materials.
- 著者
- Charose Marie Ting Perez Kenshi Watanabe Yoshiko Okamura Yutaka Nakashimada Tsunehiro Aki
- 出版者
- Japan Oil Chemists' Society
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- pp.ess19020, (Released:2019-05-16)
- 被引用文献数
- 11
Thraustochytrids, a group of marine protists, are continuously gaining attention due to their capability in producing lipids for various biotechnological applications towards foods, medicines, chemicals, and biofuels. Although various substrates, predominantly glucose, have been used as carbon source for this microalga, it is desirable to adopt cheaper and more diversified substrate to expand their application range. In this study, we aimed to examine the ability of acetate, which can be easily generated from various resources by acetogenic microorganisms, as a substrate of Aurantiochytrium limacinum SR21. As a result of flask-scale analysis, specific growth rates (µ) of the strain SR21 grown in 3% acetate- or glucose-based medium were 0.55 and 0.98 h–1, respectively. The maximum yield of total fatty acid in acetate medium was 4.8 g/L at 48 h while that in glucose medium was 6.8 g/L at 30 h, indicating that acetate has potential as substrate. Metabolome analysis was performed to comprehensively elucidate characteristic metabolic fluctuations caused by acetate assimilation and identify targets to improve the fatty acid productivity from acetate. It was found that the use of glyoxylate cycle, which bypasses release of energy molecules such as NADH and GTP, and the inhibition of utilization of compounds from TCA cycle for anabolic reactions, may cause the slow growth in acetate which has an effect also in lipid productivity. The activity of the pentose phosphate pathway was found to be weak in acetate cultivation, thus NADPH was mainly produced in malate-pyruvate cycle. Lastly, mevalonate pathway was found to be activated in acetate cultivation which additionally competes with acetyl-CoA as starting material of fatty acid synthesis.
- 著者
- Seiji KAWAMOTO Mitsuoki KANEOKE Kayo OHKOUCHI Yuichi AMANO Yuki TAKAOKA Kazunori KUME Tsunehiro AKI Susumu YAMASHITA Ken-ichi WATANABE Motoni KADOWAKI Dai HIRATA Kazuhisa ONO
- 出版者
- (社)日本農芸化学会
- 雑誌
- Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)
- 巻号頁・発行日
- vol.75, no.1, pp.140-144, 2011-01-23 (Released:2011-01-23)
- 参考文献数
- 15
- 被引用文献数
- 22
We tested the effect of oral administration of fermented sake lees with lactic acid bacteria (FESLAB) on a murine model of allergic rhinitis upon immunization and nasal sensitization with ovalbumin (OVA). We used Lactobacillus paracasei NPSRIk-4 (isolated from sake lees), and L. brevis NPSRIv-8 (from fermented milk) as starter strains to produce the FESLAB. Oral FESLAB administration resulted in the development of significantly fewer sneezing symptoms than those seen in sham control animals given sterile water. We also found that FESLAB suppressed the allergen-induced degranulation of RBL2H3 rat basophilic leukemia cells.