Saccharomyces cerevisiae CY 균주에 의한Phytase의 생성과 반응특성 = Production and Reaction Properties of Phytaseby Saccharomyces cerevisiae CY strain

국문 초록 (Abstract)

Saccharomyces cerevisiae CY 균주에 의한 phytase의 생성은 진탕배양인 경우가 정치배양에 비하여 약 2배의 생성도를 보였다. CY 균주의 phytase는 세포내 효소활성이 세포외 효소활성에 비하여 약 3-4배 높게 나타났으나, 포도당이 1%로 저농도로 첨가된 배지에서는 세포내 효소활성과 세포외 효소활성의 분포비율이 1 : 1 정도로 유사한 비율로 나타났다. 세포내외로 생성된 총 phytase 활성은 포도당의 첨가농도에 상관없이 대략 1,000 mU/ml에 이르렀으며, 건조균체당 효소활성은 지수성장 말기에 170-190 mU/mg-DCW 범위에서 최대활성을 보였다. CY 균주의 세포내 효소의 최적 반응pH는 3.5이었으며, 최적 반응온도는 37-40oC이었다. 배양액에 존재하는 phytate는 성장하는 CY 균주에 의하여 배양 36시간째 4.3 mM phytate의 약 95% 가 분해되었으며, 0.4 mg-DCW/ml의 균체농도를 갖는 현탁균체 반응액에서는 분해반응 12시간째 phytate의 약 90% 이상이 효율적으로 분해되었다.

다국어 초록 (Multilingual Abstract)

A yeast strain producing phytase, isolated from a mash of Korean traditional Yakju, was identified as a strain of Saccharomyces cerevisiae and designated as Saccharomyces cerevisiae CY strain. Phytase was produced by CY strain both intracellularly and extracellularly. Total phytase activity by the shaking culture was about two times higher than that of the static culture. The portion of extracellular phytase to total phytase activity ranged between 23 and 49 percent, depending on the glucose concentration in the culture medium. Phytase production was reached at approximately 1 U/ml as total phytase activity and the maximum intracellular phytase activity was 0.17-0.19 U/mg-DCW at late logarithmic growth phase. The optimum reaction pH and temperature of intracellular phytase were 3.5 and 40oC, respectively. Over 95% of the phytate was degraded by growing cells after 36 hours yeast cell culture and about 90% of total phytate was effectively degraded by suspending the whole cell with the biomass of 0.4 mg-DCW/ml-reaction solution after 12 hours degradation reaction.

참고문헌 (Reference)

1 "Utilization of phytate by some yeasts" 61-66, 1992

2 "Sensitive method for therapid determination of phytate in cereals and cereal products" 1423-1426, 1983

3 "Purificationand properties of an extracellular acid phytase from Pseudomonasfragi Y9451" 14 : 1004-1008, 2004

4 "Purification and properties of the phytase fromSchwanniomyces castellii" 7-11, 1992

5 "Purification and characterization of phytasefrom Bacillus subtilis" 1266-77 1269, 1992

6 "Production, purification and propertiesof microbial phytases." 77 : 203-214, 2001

7 "Production ofphytase in a low phosphate medium by a novel yeast Candidakrusei" 92 : 154-160, 2001

8 "Production of phytatehydrolyzing enzyme by some fungi" 377-382, 1983

9 "Phytic acidinteractions with divalent cations in foods and in thegastrointestinal track" 161-171, 1989

10 "Phytases: microbialsources, production, purification, and potential biotechnologicalapplications." 23 : 29-60, 2003

11 "Phytaseactivity in fermentative microflora of dough" and wrzecio : 67-73, 1987

12 "Phytase production bythe yeast, Pichia anomala." 23 : 551-554, 2001

13 "Phytase of theyeast Arxula adeninivorans" 21 : 33-38, 1999

14 "Mould phytases and their application in the foodindustry" 467-472, 1992

15 "Isolation and identification ofphytase-producing bacterium, Enterobacter sp. 4, and enzymaticproperties of phytase enzyme." 18 : 449-454, 1996

16 "Influence of culture conditions on the biosynthesis ofSchwanniomyces castellii phytase" 399-404, 1993

17 "Enzymaticelimination of phytate in soybean milk" 32 174-180, 1985

18 "Effects of soaking incubation and autoclaving on phytic acid in seeds" 516-521, 1985

19 "Degradation of phytic acid in Chungkookjang fermented withphytase producing bacteria" 423-428, 1990

20 "Antinutrient effects of phytate" 429-432, 1994

21 "Advances in Food Research 28" 1-92, 1982