Abstract
Yeast strains with good sensory properties were selected, and those yeasts were subjected to mutation to develop high glutathione producing yeasts. In addition, the antiradical activity and flavoring effect of the yeast extract were evaluated. A total of 68 strains were screened, and three strains of Saccharomyces utilis, four strains of Candida utilis, and one strain of Zygosaccharomyces rouxii were selected based on the flavoring effect. Among them, a random mutation was elicited against SEM-Y8, resulting in a high flavoring effect and growth rate. The glutathione production by SEM-Y8 increased 2.0-fold following the mutation, and the DPPH radical quenching effect of the SY8-M2-1-derived extract increased 3.2-fold compared to that of the wild type. The sensory properties of the SY8-M2-1-derived extract were better than those of garlic or onion extract in umami and mouthfulness. Thus, the SY8-M2-1 extract could be used as a functional flavoring material with improved antiradical activity.
본 연구에서는 다양한 효모 배양액을 자가소화 시킨 후 관능검사를 통해 1차적으로 8종(S. cerevisiae 3종, C. utilis 4종 및 Z.rouxii 1종)을 선별하였다. 이 중 정미성과 균체 성장율을 고려하여 C. utilis인 SEM-Y8을 선정하여 고글루타치온 생산을 위한 균주 개량을 수행하였다. 두 번의 UV 처리를 통해 SEM-Y8보다 글루타치온 생성능이 2.0배 증가된 SY8-M2-1 개량 효모 균주를 얻었으며, 선택배지(4.0% yeast extract, 1.5% glucose, 0.04% $NH_4H_2PO_4$, 0.04% L-cystein)를 사용함으로써 글루타치온 함량을 1.5배 더 향상시킬 수 있었다. 이상의 조건에서 얻어진 고글루타치온 함유 효모추출물은 마늘과 양파엑기스보다 우수한 감칠맛과 부드럽고 깊은 맛을 나타내었으며, SEM-Y8 대비 3.2배 향상된 라디컬 소거능을 나타내었다.
