Quantitative stability of the folates highly accumulated in a non-Kyokai sake yeast.
J Gen Appl Microbiol
; 67(5): 214-219, 2021 Nov 25.
Article
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| MEDLINE
| ID: mdl-34373370
ABSTRACT
Pressed sake cake, a by-product of sake brewing, is a rich dietary source of folates, which are important vitamins for humans. However, considerable losses of folates occur during storage and cooking. We have previously reported that Km67, the house sake yeast strain of Kiku-masamune sake brewery, can accumulate high folate levels. In this study, we found that the folate content of pressed sake cakes produced with Km67 remained at approximately their maximum level after the fermentation activity stopped. To elucidate the mechanisms of high folate accumulation in Km67, we analyzed the expression of 23 folate-metabolizing genes. The expression of ABZ1 and FOL3 was almost always higher in Km67 than in Kyokai no. 701 yeast (K701), which suggested that enhanced expression of the genes involved in folate biosynthesis was a mechanism of high folate accumulation in Km67. We found that the folates of Km67 pressed sake cakes were quantitatively stable at 4°C under refrigerated storage conditions. In addition, the homocysteine content of Km67 pressed sake cakes was almost always higher than that of K701 pressed sake cakes. This result suggests that a reason for high folate accumulation in Km67 yeast is the need to reduce the intracellular concentration of homocysteine. Our results provide biologically meaningful information on folate metabolism in yeast.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Saccharomyces cerevisiae
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Proteínas de Saccharomyces cerevisiae
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Bebidas Alcohólicas
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Ácido Fólico
Idioma:
En
Revista:
J Gen Appl Microbiol
Año:
2021
Tipo del documento:
Article