Abstract
In searching for yeast to be utilized as biocontrol agents, a single yeast strain was isolated from Camellia sinensis based on its morphological, cultural, physiological, and biochemical properties, as well as by molecular techniques. This single strain was pink to red in color and designated as strain JY-1. The effects of temperature, pH, NaCl concentration, and ethanol concentration on the growth of the JY-l strain were examined for the JY-1. Growth occurred at temperatures ranging from 20 to $35^{\circ}C$, and between pH 3.0 and 12.0, with optimal growth at $25-30^{\circ}C$ and pH 5.0. The yeast also grew in the presence of 0-2% (w/v) NaCl and 0-4% (v/v) EtOH. The isolate was further classified based on biochemical characteristics using the VITEK system. The biochemical data obtained using this system were similar to those of Rhodotorula glutinis/Rhodotorula mucilaginosa (exhibiting a 93% matching level). Molecular phylogenetic analysis based on l8S rDNA sequences indicated that the yeast represented a basidiomycetous species, and its highest degree of sequence similarity was with Rhodosporidium azoricum, strain JCM11251 (99%).
발효차로부터 분리 동정한 JY-1 효모는 18S rDNA 유전자 분석에서는 Rhodosporidium azoricum과의 유의성 99%, 생화학적 분석 VITEK system에서는 Rhodotorula glutinis/Rhodotorula mucilaginosa와 93%의 유의성을 나타내였다. 배양조건에서 최적의 온도는 $25-30^{\circ}C$, pH는 5.0이었으며 염의 농도는 2%, 최적의 에탄올 농도는 4%이었다. 일반적인 실험결과에서도 Rhodosporidium 속의 특이성과 비교하여 보았을 때 형태적, 생리적, 생화학적 유사성을 나타내었다. 이상의 결과에서 앞으로의 연구과제는 많이 음용되고 있는 발효차와 관련한 또 다른 미생물군을 분리 동정하여 우수한 균주를 확보하는데 있으며 이를 이용한 발효차 음료산업 개발에 목적을 두고 있다.