Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Macaé, RJ, Brazil.
Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, SP, Brazil.
J Appl Microbiol. 2019 May;126(5):1402-1413. doi: 10.1111/jam.14206. Epub 2019 Mar 19.
To screen and identify a potential biosurfactant-producing yeast strain isolated from Antarctic soil and to evaluate the fermentation process kinetics of the most promising strain on biosurfactant production using glycerol as carbon source.
From the 68 isolated yeast strains, 11 strains were able to produce biosurfactants after Emulsification Index (E.I.) and Drop Collapse tests, reaching an E.I. higher than 10%. Strain 1_4.0 was the best producer, identified as Candida glaebosa based on molecular analysis. Yeast was cultivated in a medium composed of glycerol supplemented with yeast extract for 120 h to determine the process kinetics. The increased C/N ratio affected yeast growth and biosurfactant production. Biosurfactant release was associated with the end of exponential and beginning of the stationary growth phases. Results indicated an E.I. of 30% at the end of the fermentation.
The feasiability of C. glaebosa to produce biosurfactant from a low-cost medium cultivation shows a great impact on the development of bioresource in the Antarctica terrestrial environment.
Although the diversity of psychrophilic/psychrotolerant micro-organisms from Antarctica has been the preferred subject of study by microbiologists, terrestrial microfungal communities are scarcely investigated and literature about the biotechnological potential of such micro-organisms should cover important biomolecules in addition to cold-adapted enzymes. In the present study, for the first time, the Maritime Antarctica environment was screened as a novel source of biosurfactants produced by micro-organisms.
从南极土壤中筛选和鉴定一株潜在的产生物表面活性剂的酵母菌株，并评估最有前途的菌株在以甘油为碳源生产生物表面活性剂方面的发酵过程动力学。
从 68 株分离的酵母菌株中，有 11 株在乳化指数（E.I.）和滴崩试验后能够产生生物表面活性剂，达到 E.I.高于 10%。菌株 1_4.0 是最好的产生产者，根据分子分析鉴定为假丝酵母。酵母在含有酵母提取物的甘油培养基中培养 120 小时，以确定过程动力学。增加的 C/N 比对酵母生长和生物表面活性剂的生产有影响。生物表面活性剂的释放与指数生长和静止生长阶段的结束有关。结果表明，发酵结束时 E.I.为 30%。
假丝酵母能够从低成本培养基中生产生物表面活性剂，这对开发南极洲陆地环境中的生物资源具有重要意义。
尽管来自南极洲的嗜冷/耐冷微生物的多样性一直是微生物学家研究的首选课题，但陆地微生物群落的研究甚少，关于此类微生物的生物技术潜力的文献除了冷适应酶外，还应涵盖重要的生物分子。在本研究中，首次对南极海洋环境进行了筛选，作为微生物产生的生物表面活性剂的新来源。
