Studies on Screening and Isolation of Esterase Inhibitors from Soil Microorganisms (II). Isolation of Inhibitors and Associated Lipids from Streptomyces Strain DMC-498

한국 토양균중 Esterase 저해제 검색 및 분리에 관한 연구(제 2 보) Streptomyces Strain DMC-498 균주의 저해성분 및 관련 지질의 분리

To find esterase inhibitors and in the metabolites of Streptomyces strain DMC-498, two active compounds were isolated from the methanol extract of the mycelia of the strain by Silica gel column chromatography and preparatory argentation TLC. These compounds were proved to show competitive inhibition. Compound B was found to consist of linoleic and oleic acids. Fifty percent inhibition concentration ($lC_{50}$) of linoleic acid was $0.045\mu\textrm{g}/ml$, whereas oleic acid exhibited no inhibitory activity. Associated lipids: isostearic acid, isostearic acid methyl ester, oleic acid methyl ester and linoleic acid methyl ester, were isolated from the same extract, showing no inhibition of the esterase. Compound A was found to be a liquid inhibitor with an alicyclic ring and two or more oxygens, its molecular weight being more than 500.

한국 토양균 중에서 esterase 저해제를 생산하는 균주인 Streptomyces strain DMC-498을 oatmeal yeast extract 배지에서 3일간 액내 배양하였을 때 최고의 저해작용을 나타내었으며 균사체의 메탄올 추출물로부터 저해제를 분리하였다. linoleic acid가 저해작용이 있음을 확인하였으며 50% 저해작용을 나타내는 linoleic acid의 양은 $0.045\;\mu\textrm{g}/ml$이었다. 활성이 보다 큰 compound A는 분자량이 500 이상이며 산소를 2개이상 함유하고 있는 환상구조의 지방족 화합물로 생각된다. 이것을 상경적 저해작용을 나타내었다. DMC-498 균주가 함유하는 지질의 주성분은 isostearic acid, isostearic acid methyl ester, linoleic acid methyl ester 및 oleic acid methyl ester이었다.