Department of Fermentation Science, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo, Japan.
Department of Fermentation Science and Technology, Graduate School of Applied Bioscience, Tokyo University of Agriculture, Tokyo, Japan.
J Appl Microbiol. 2022 Feb;132(2):1104-1111. doi: 10.1111/jam.15259. Epub 2021 Aug 26.
This study aimed at obtaining a novel fructooligosaccharides (FOS)-producing yeast, which was different from conventional FOS producers, Aureobasidium spp.
Strain Him3 was newly isolated from a Japanese dried sweet potato as a FOS producer. The strain exhibited yeast-like cells and melanization on the potato dextrose agar medium, and formed very weak pseudomycelia on the yeast extract polypeptone dextrose agar medium. Based on the internal transcribed spacer (ITS) region of ribosomal DNA and a partial β-tubulin gene sequences, the strain Him3 was identified as Zalaria sp. The β-fructofuranosidase (FFase) produced by strain Him3 was localized on the cell surface (CS-FFase) as well as in the culture broth (EC-FFase). The FOS production yields by CS-FFase and EC-FFase from 50% sucrose were 63.8% and 64.6%, respectively, to consumed sucrose after the reaction for 72 h.
We successfully isolated a novel black yeast, Zalaria sp. Him3, with effective capacity for FOS production. Phylogenetic analysis revealed that strain Him3 was distantly related with the conventional FOS producers, Aureobasidium spp.
Since FFase of strain Him3 demonstrated high production yields of FOS, it could be applied to novel industrial production of FOS, which is different from conventional methods.
本研究旨在获得一种不同于传统低聚果糖（FOS）生产菌——金孢子菌属的新型 FOS 生产酵母。
菌株 Him3 是从日本干甘薯中分离得到的一种 FOS 生产菌。该菌株表现出酵母样细胞和在土豆葡萄糖琼脂培养基上的黑化现象，在酵母提取物多肽葡萄糖琼脂培养基上形成非常弱的假菌丝。基于核糖体 DNA 的内部转录间隔区（ITS）区域和部分 β-微管蛋白基因序列，菌株 Him3 被鉴定为节菱孢属。菌株 Him3 产生的 β-果糖呋喃糖苷酶（FFase）定位于细胞表面（CS-FFase）和培养上清液（EC-FFase）中。CS-FFase 和 EC-FFase 从 50%蔗糖中生产 FOS 的产率分别为 63.8%和 64.6%，反应 72 小时后消耗蔗糖。
我们成功分离到一种新型黑酵母，节菱孢属 Him3，具有有效生产 FOS 的能力。系统发育分析表明，菌株 Him3 与传统的 FOS 生产菌——金孢子菌属亲缘关系较远。
由于菌株 Him3 的 FFase 具有较高的 FOS 生产产率，因此可应用于新型 FOS 的工业生产，这与传统方法不同。
