Studies on the Induction of Available Mutants of Takju Yeast by UV light Irradiation (Part 1) -On the Selection and Identification of the Mutants-

자외선조사(紫外線照射)에 의한 탁주효모(酵母)의 변이주육성(變異株育成)에 관한 연구(제 1 보) -변이주(變異株)의 선정(選定) 및 동정(同定)-

These studies were conducted to induce the available mutants in Takju yeasts by the irradiation of UV light. Two original strains(5-Y-5, 6-Y-6) using for irradiation of UV selected from 24 strains which were isolated from the Takju mashes And Nuruks collected from 12 local regions of Chungnam and Chungbuk provinces in Korea, and the irradiations to the yeasts with UV light were carried out at a distance 10-40cm from the sources of irradiation for 10-220 seconds. The purpose of this experiment is to report the effects of irradiating distances and times of UV light on the survival ratio of orginal yeasts, and the identification of two orginal yeasts and three mutants induced by the irradiation of UV light. The results were summarized as follows. 1) The effects of irradiating distances and times on the survival ratio on the yeasts were represented as follows. and acid productivity to the survival strains by the irradiation of UV light. The selected mutants were the strains 30-24, 40-27 which have more powerful fermentability about 10 percent than those of original strains and a strain 30-81 which have potential acid productivity. 3) The selected yeasts (5-Y-5, 6-Y-6) were identified to Saccharomyces cerevisiae by a taxonomic study of Lodder and the mutants(30-81, 40-27, 30-81) induced from above yeasts by the irradiation of UV light have almost same properties two orginal yeasts in the identical characteristics.

충남북(忠南北)의 12개지역(個地域)에서 수집한 탁약주 술덧과 누룩에서 24주(株)의 효모(酵母)를 분리(分離)한 후(後) 발효력(醱酵力)이 강(强)한 2균주(菌株)를 모균(母菌)으로 선정(選定)하여 여러 조건하(條件下)에서 자외선(紫外線)을 조사(照射)시켜 그 효모(酵母)의 생존율(生存率)을 측정(測定)하고 또한 선정(選定)한 2모균주(母菌株)와 자외선조사(紫外線照射)로 얻은 3변이주(變異株)의 균학적(菌學的) 제성질(諸性質)을 조사(調査)하여 다음과 같은 결과(結果)를 얻었다. 1. 자외선(紫外線) 조사(照射)에 의(依)한 선정효모(選定酵母)의 생존율(生存率)은 다음과 같다. 조사거리(照射距離) 10(cm) 20 30 40 1%생존율(生存率) 1(sec) 20 $30{\sim}40$ $70{\sim}90$ 0.1%생존율(生存率) $15{\sim}20(sec)$ 40 $60{\sim}70$ $140{\sim}160$ 완전사멸(完全死滅) >25(sec) >60 >90 >220 2. 선정효모(選定酵母)에 자외선(紫外線)을 조사(照射)시켜 0.1% 생존율구(生存率區)에서 발육(發育)한 균주(菌株)들의 발효력(醱酵力)을 측정(測定)하여 발효력(醱酵力)이 모균(母菌)보다 약(約) 10% 강(强)한 $30{\sim}24$ 및 $40{\sim}27$의 2균주(菌株)와 모균(母菌)에서는 없든 강(强)한 생산능(生酸能)을 보인 $30{\sim}81$ 균주(菌洙)를 선정(選定)하였다. 3. 선정효모(選定酵母)를 Lodder의 분리법(分離法)으로 동정(同定)한 결과(結果) Saccharomyces cerevisiae로 동정(同定)되었으며 3변이주(變異株)들도 동정상(同定上)의 특성(特性)에는 그 모균(母菌)들과 다름이 없었다.