• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.791-797
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• 1999

This study was conducted in order to evaluate nutritive values of yeasts (Kluyveromyces fragilis and Candida utilis) according to growth stages (early log phase, log phase, stationary phase and death phase) and chemical treatment of their cell wall, Proximate, amino acids, fatty acids and nucleotides composition of the yeast samples was determined. Crude protein content was high in K. fragilis ($48\~59\%$) compared to C. utilis ($26\~43\%$). Crude lipid and fiber contents of the yeasts were below than $1.6\%$ and $3.3\%$, respectively. Conposition of aspartic acid, glycine, proline, leucine, Iysine and valine of K. fragilis were higher than those of C. utilis, and glutamic acid and arginine of C. utilis were higher than those of K. fragilis. Proximate and amino acids composition was not siginificantly influenced by growth stage of the yeasts. Major fatty acids of the yeasts in all growth stages were $C_{10-18}$. $C_{16-18}$ contents were relatively high in the early log or log phase and $C_{10-12}$ contents were relatively high in the stationary or death phase. However, n-3 highly unasturated fatty acids (C$\ge$20) in the all growth stages were not observed. This result indicated that these yeast strains could not be adequate as a dietary lipid source for marine fish. Composition of nucleotides and their related compounds (ATP ADP AMP, IMP and inosine) in the early log phase yeasts were lower than those in the log, stationary and death phase yeasts.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.204-212
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• 1994

To estimate the possibility of wine-making with Korean dried persimmon, its homogenized and filtered solution was fermented at $15^{\circ}C$ and $25^{\circ}C$ for 12 weeks with Saccharomyces cerevisiae (Japan Alcoholic Beverage Association N0.7). Sugars of dried persimmon were mainly composed of 27.02% of glucose, 19.81% of fructose and 5.12% of mannose. In the fermentation at $25^{\circ}C$, glucose was almost completely consumed in 8 days, but fructose and mannose were consumed up to 64% and 74%, respectively, in the same period and were not utilized any more afterwards. In the fermentation at $15^{\circ}C$, 75% of glucose, 20% of fructose and 49% of mannose were consumed in 8 days and these sugars were continuously utilized for 12 weeks. Organic acids in the homogenized and filtered solution were levulinic acid (148.6 mg%), 4-methylvaleric acid (73.5 mg%), oxalic acid (28.7 mg%), acetic acid (8.5 mg%), N-butyric acid (8.4 mg%) and succinic acid (6.7 mg%). Irrespective of fermentation temperature, levulinic acid rapidly reduced according to progression of fermentation. Oxalic acid, N-butyric acid and succinic acid decreased at 2nd day of fermentation, and then increased at 4th and 6th days and subsequently decreased again under the levels of the solution. Acetic acid and 4-methylvaleric acid increased with the proceeding of fermentation and at 12th week of fermentation these contents were more than those of the solution. The contents of total free amino acid significantly reduced at 2th day of fermentation and then increased to the level of the solution at 12th week irrespective of fermentation temperature. Ethanol content rapidly increased to the levels of 5.3(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$ to 8th day after fermentation, but at 12th week its content was 14.5%(v/v) at $15^{\circ}C$ and 9.4%(v/v) at $25^{\circ}C$. The higher alcohots identified were 2-methyl-l-propanol, 3-methyl-ibutanol, 2-methyl-l-butanol and 2-methyl-2-propanol and the range of those contents was from 0.001% (v/v) to 0.06%(v/v). The color of the wine fermented at $15^{\circ}C$ was slightly superior but flavor and taste were slightly superior in the wine fermented at $25^{\circ}C$.

• Journal of Food Hygiene and Safety
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• v.21 no.2
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• pp.100-106
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• 2006

The use of underarm and body care cosmetics with oestrogenic chemical excipients (particularly the parabens) and the hypothesized association with breast cancer incidence, particularly in women. It is noted that the type of cosmetic product is irrelevant (e.g. antiperspirant/deodorant versus body lotion, moisturizers or sprays versus creams) and attention must focus on issues of actual exposure to chemicals through continued dermal application of body care products and the endocrine/hormonal activity and toxicity of the chemicals in the formulations. To evaluate the estrogenic activities of parabens such as ethylparaben, butylparaben, propylparaben, isobutylparaben and isopropylparaben, we used recombinant yeasts containing the human estrogen receptor [Saccharomyces cerevisiae ER+LYS 8127], human breast cancer MCF-7 cell lines and human estrogen receptor ${\alpha}\;and\;{\beta}$. In E-screen assays, isopropylparaben is the most estrogenic paraben, and in ER competition assay, isobutylparaben is the most estrogenic paraben. We evaluated isopropylparaben was most active in the recombinant yeast assay, followed by propylparaben, ethylparaben, isobutylparaben and butylparaben. Results from this study demonstrate that parabens are observed in human endocrine system. Therefore, we have shown that the parabens is induced the estrogenic activities similar to $17{\beta}$-estradiol and Bisphenol-A.