Lipid Composition of Freeze-Tolerant Baker's Yeasts

냉동내성빵효모의 지질분석

  • Hahn, Young-Sook (Department of Food and Nutrition, Sungshin Women′s University) ;
  • Hiroyasu Kawai (Department of Food and Nutrition, Nara Women′s University)
  • Published : 1995.02.01

Abstract

The molar ratio of sterol to phospholipid differed from yeast strains, and the ratio was relatively higher in non-freeze-tolerant yeast strain, S. cerevisiae than freeze-tolerant yeast strains, D$\sub$2-4/ or CFY. Phospholipid composition of these yeast were also investigated. Phosphatidylcholine content was larger among phospholipids in all yeasts. Higher ratio of PC/PE was found in freeze-tolerant yeast than non-freeze-tolerant yeast. Higher proportion of linolein acid(18 : 2) against total fatty acid attached to phospholipid was observed in D$\sub$2-4/ than S. cerevisiae or CFY, and the degree of unsaturation of fatty acid was higher in D$\sub$2-4/ and CFY than in S. cerevisiae. These results suggested that the fluidity of yeast cell membrane was different in yeast strains, which might result in the difference in freeze-injury of yeast at low temperatures.

냉동내성빵효모의 냉동내성기구를 규명하기위한 일환으로 세포의 막 유동성에 관계되는 지질분석을 행하였다. 그 결과, 냉동내성효모 $D_{2-4}$나 CFY보다 비냉동내성 효모 Saccharomyces cerevisiae 2001이 스테롤 : 인지질의 비율이 비교적 높았다. 또 인지질조성이 조사되었는 데, 세효모 모두에 있어 phosphatidylcholine 함량이 가장 높았다. Phosphatidylcholine : phosphatidylethanolamine의 비율은 냉동내성효모가 비내성효모 보다 높게 나타났다. 인지질에 연결된 지방산 함량을 보면, linoleic acid 함량은 $D_{2-4}$에서 높게 나타났으며 지방산의 불포화도는 $D_{2-4}$가 CFY나 S. cerevisiae보다 높았다. 이 결과에서 yeast 세포막의 유동성은 각 효모마다 다르며, 이것들이 저온에서의 효모의 동결장해에 영향을 주는 것으로 생각된다. 생각된다.

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