• Journal of Microbiology and Biotechnology
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• 제24권12호
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• pp.1622-1628
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• 2014

DagA, a ${\beta}$-agarase, was produced by cultivating a recombinant Streptomyces lividans in a glucose medium or a mixed-sugar medium simulating microalgae hydrolysate. The optimum composition of the glucose medium was identified as 25 g/l glucose, 10 g/l yeast extract, and $5g/l\;MgCl_2{\cdot}6H_2O$. With this, a DagA activity of 7.26 U/ml could be obtained. When a mixed-sugar medium containing 25 g/l of sugars was used, a DagA activity of 4.81 U/ml was obtained with very low substrate utilization efficiency owing to the catabolic repression of glucose against the other sugars. When glucose and galactose were removed from the medium, an unexpectedly high DagA activity of about 8.7 U/ml was obtained, even though a smaller amount of sugars was used. It is recommended for better substrate utilization and process economics that glucose and galactose be eliminated from the medium, by being consumed by some other useful applications, before the production of DagA.

• Preventive Nutrition and Food Science
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• 제18권2호
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• pp.124-132
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• 2013

In this study, novel peptides (NIPP-1, NIPP-2) derived from Navicula incerta (microalgae) protein hydrolysate were explored for their inhibitory effects on collagen release in hepatic fibrosis with the investigation of its underlying mechanism of action. TGF-${\beta}1$ activated fibrosis in LX-2 cells was examined in the presence or absence of purified peptides NIPP-1 and NIPP-2. Besides the mechanisms of liver cell injury, protective effects of NIPP-1 and NIPP-2 were studied to show the protective mechanism against TGF-${\beta}1$ stimulated fibrogenesis. Our results showed that the core protein of NIPP-1 peptide prevented fibril formation of type I collagen, elevated the MMP level and inhibited TIMP production in a dose-dependent manner. The treatment of NIPP-1 and NIPP-2 on TGF-${\beta}1$ induced LX-2 cells alleviated hepatic fibrosis. Moreover, ${\alpha}$-SMA, TIMPs, collagen and PDGF in the NIPP-1 treated groups were significantly decreased. Therefore, it could be suggested that NIPP-1 has potential to be used in anti-fibrosis treatment.

• 한국미생물·생명공학회지
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• 제44권4호
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• pp.522-528
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• 2016

본 연구에서는 3종류의 목질계 바이오매스와 4종류의 해조류 바이오매스를 전처리와 효소가수분해 과정을 통하여 얻은 환원당을 이용하여 C. saccharophila를 배양하였다. 얻어진 가수분해물을 활성탄 처리 유무에 따라 배양한 결과, 목질계 바이오매스와 해조류 바이오매스 가수분해물을 활성탄 처리하지 않은 경우에는 C. saccharophila의 성장이 저해되었다. 목질계 바이오매스인 유채대와 보리대 그리고 볏짚과 해조류 바이오매스인 미역, 다시마, 파래 그리고 꼬시래기 가수분해물의 경우 활성탄 등으로 처리한 경우에서 목질계 바이오매스와 해조류 바이오매스 가수분해물에서 C. saccharophila의 성장이 관찰되었다. 미세조류의 생산성과 oil 함량, chlorophyll 등을 고려하였을 때 목질계 바이오매스와 해조류 바이오매스는 C. saccharophila의 product 생산을 위한 배양에 이점을 가지며, 특히 chlorophyll 생산에 보다 유용하리라 판단된다.