• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1174-1178
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• 2006

An experiment was conducted to investigate the effects of dietary supplementation of copper chelates in the form of methionine, chitosan and yeast on the performance of laying hens. Four hundred ISA Brown layers, 84 wks old, were assigned to 4 treatments: control, 100 ppm Cu in methionine chelate (Met-Cu), 100 ppm Cu as chitosan chelate (Chitosan-Cu) and 100 ppm Cu as yeast chelate (Yeast-Cu). Each treatment had five replicates of 20 hens. Hen-day and hen-housed egg production and egg weight were significantly (p<0.05) increased by Met-Cu supplementation. The increase by Chitosan-Cu and Yeast-Cu supplementation was not significant. Contrast of the control vs. Cu chelates showed egg weight was significantly (p<0.05) increased by Cu chelate supplementation. Soft-shell egg production was significantly (p<0.05) reduced by supplementation of Cu chelates. Met-Cu treatment showed the lowest incidence of soft egg production. Gizzard erosion index was increased by Cu chelate supplementation. Crude fat in liver, total cholesterol in yolk and Cu content in liver and yolk were not significantly influenced by Cu chelate supplementation. It was concluded that dietary supplementation of 100 ppm Cu as Met-Cu significantly increased egg production and egg weight. Cu-Met chelate was also effective in reducing soft-shell egg production but increased gizzard erosion index.

• KSBB Journal
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• v.19 no.4
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• pp.245-249
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• 2004

A combined method of autolysis and enzymatic hydrolysis of baker's yeast was developed for the production of yeast extract, which is widely used as a natural food ingredient. From statistical analysis, NaCl and ethanol addition were found to be significantly effective factors in autolysis of yeast. The optimum dosages of salt and ethanol were 3% and 1%, respectively. Heat treatment and the use of cell lytic enzyme were not significantly effecting on the autolysis. Yeast hydrolysate was prepared by autolysis, followed by enzymatic hydrolysis using proteases, nuclease and deaminase. Additionally, the hydrolysate was processed by downstream process including Maillard reaction and debittering. The total dry matter yield and total nitrogen yield for the process were 76% and 59%, respectively. Compared to a process using brewer's yeast, when baker's yeast was used as a raw material, a higher recovery yield was obtained.

• Korean Journal of Agricultural Science
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• v.46 no.2
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• pp.229-237
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• 2019

The influence of dietary supplementation with a yeast culture on growth performance, fecal score and nutrient digestibility was evaluated in weaned pigs in a 6-week feeding trial. A total of 50 weaning pigs with an initial average body weight (BW) of $7.46{\pm}1.60kg$ were randomly allotted into 1 of 2 dietary treatments according to the initial BW. There were 5 replicate pens in each treatment with 5 pigs per pen. The dietary treatments were as follows: 1) control, basal diet (CON) and 2) 0.10% yeast culture, basal diet supplemented with 0.1% yeast culture (YC). The average daily feed intake was significantly improved with the dietary supplementation of the yeast culture compared with the control during phases 1 and 3. Overall (0 to 6 weeks), dietary supplementation with the 0.1% yeast culture had a significant effect on the feed conversion ratio (FCR). There was no significant difference in the fecal score between the CON and YC dietary treatments. In addition, no difference in the apparent total tract digestibility was observed between the CON and YC dietary treatments. Collectively, the results of this study indicate that dietary supplementation of 0.1% yeast only improved the feed intake of weaning pigs; however, yeast culture supplementation did not affect the average daily gain, feed efficiency, total tract digestibility of dry matter, and nitrogen and energy levels as well as the fecal scores.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.485-488
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• 2007

Plentiful amount of spent yeast has been produced as a by-product from breweries. ${\beta}-Glucan$ was prepared from the spent brewer's yeast in a crude form with hot water extraction and subsequent enzymatic treatment. The crude ${\beta}-glucan$ preparation consisted of mainly glucan (53% of total wt), containing approximately 35% ${\beta}-glucan$ content of total weight. The effects of crude ${\beta}-glucan$ substitution (1-9%) on pasting properties of wheat flour and starch were determined using a Rapid Visco-Analyzer (RVA). Incorporation of yeast ${\beta}-glucan$ into wheat flour and starch significantly decreased peak and [mal viscosities, but slightly increased setback viscosity. The setback viscosity was considerably higher in starch/${\beta}-glucan$ suspension than in flour/${\beta}-glucan$ suspension. It was suggested that preparation of yeast ${\beta}-glucan$ into aqueous dispersion might affect pasting behaviors of wheat flour and starch.

• Korean Journal of Microbiology
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• v.14 no.1
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• pp.1-7
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• 1976

Effect of some nutrients on the growth of 3 yeast strains in the pulp mill waste liquor was determined during an attempt to lower the BOD content of the waste liquor and to produce the fodder yeast. The strains applied were Debaryomyces castelli Capriotti, D.phoffi Capriotti, and Cryptococcus luteolus (Saito)Skinner. The necessity of the addition of 0.2% ${NH_4}2SO_4$ 0.5% yeast extract, 0.2% $NH_2SO_4$, and 0.1% $MgSO_4$.$7H_2$O for the best growth of all three strains in the waste liquor was ascertained as a result. After 3-day treatment of the yeast cells on the waste liquor, the BOD content was lowered by about 60-70%. Harvested yeast cells contained ca. 75% water with 1.5-3% lipid, 40-46% protein, 50% carbohydrate and 3-5% ash on the dry weight basis, indicating the possibility of being utilized as the fodder yeast.

• Journal of Ginseng Research
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• v.10 no.1
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• pp.1-10
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• 1986

To evaluate the possible utilization of ginseng by-products, chemical components of ginseng residue, reducing ability of DPPH, effect of residue extract on the yeast growth, amino acid contents of yeast cell, increase of residue extract yield by enzyme treatment were studied. Alcohol and water extract residue contained 43-46% total reducing sugar and 14-15% crude protein, while alcohol extract residue had 0.18% n-BuOH extract. Water extract of alcohol extract residue had about 45% reducing ability of DPPH in comparison with that of alcohol extract from ginseng roots. Essential nutrients for the yeast growth were found in extract when Saccharomyces cerevisiae was cultured in Czapeck medium, a compound medium, with the residue. The addition of residue extract to malt medium, a natural medium, enhanced 30-40% yeast growth. And content of each amino acid in yeast cell cultured on malt medium with ginseng residue extract was much more than that of the cell cultured without ginseng extract, but amino acid composition of yeast cell did not differ from one another. The treatment of alcohol extract residue with cellulase increased 250% yield of residue extract.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.441-447
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• 2002

It has been well known that vanadium shows various physiological and pharmacological properties such as an insulin-mimetic effect. In view of the reported toxic effects there is the problems that the safety margin is narrow because of its strong toxicity, Vanadate was tested for its ability to cause blood aggregation. Although vanadate or $H_2O$$_2$ alone had little effect on platelet aggregation, treatment of vanadate and $H_2O$$_2$ together induced platelet aggregation indicated that it was occurred by pervandate or hydroxyl radical produced from the reaction of vanadate and $H_2O$$_2$. It was dependent on extracellular $Ca^{2+}$ion. Platelet aggregation caused by vanadate and $H_2O$$_2$ was inhibited by ascorbic acid, tocopherol, catalase, mannitol, and Tiron. In contrast to vanadate, vanadium yeast prepared by uptaking vanadate in yeast cells did not induce platelet aggregation in the presence of $H_2O$$_2$.>.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.398-402
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• 2010

[ ${\alpha}$ ]Glucosidase inhibitor is a target in the treatment of type II diabetes through the mainly inhibition of glucose levels after meals. In this study, we purified steppogenin and oxyresveratrol from the stem of Morus alba L. and examined their inhibitory activity against yeast ${\alpha}$-glucosidase. Steppogenin and oxyresveratrol were inhibited yeast ${\alpha}$-glucosidase in a dose dependent manner. The $IC_{50}$ activities (50% inhibition) were 34.4 and 9.3 ${\mu}M$, respectively. The kinetic inhibition of steppogenin showed noncompetitive inhibition ($K_m:1.1{\times}10^{-3}M$; $K_i:1{\times}10^{-5}M$), meanwhile oxyresveratrol showed competitive inhibition ($K_m:4.3{\times}10^{-3}M$; $K_i:3.4{\times}10^{-6}M$) against yeast ${\alpha}$-glucosidase. These results indicate that steppogenin and oxyresveratrol are noncompetitive and competitive inhibitors, respectively, against yeast ${\alpha}$-glucosidase.

• Journal of Animal Science and Technology
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• v.45 no.1
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• pp.49-56
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• 2003

An experiment was conducted to study the effects of the dietary Cu sources on the performance of the weanling pigs. Forty-eight, 24 in each sex, 4 weeks old pigs were assigned to four treatments; control, methionine-Cu chelate, chitosan-Cu chelate or yeast-Cu chelate. Control diet contained 136ppm Cu to which additional 100ppm Cu in different chelated form was added to the respective treatment. Individual pig weight and feed intake of each pen were recorded weekly for 5 weeks. Average daily feed intakes(ADFI), average daily gains(ADG) and ADFI/ADG were not significantly different among treatments. Nutrient availability was not also significantly affected by treatments. Serum triglyceride concentration of chitosan-Cu treatment was significantly lower than those of methionine-Cu and yeast-Cu treatments but was not significantly different from that of the control. Serum cholesterol concentration of yeast-Cu was significantly lower than those of the control and methionine-Cu but was not significantly different from that of chitosan-Cu treatment. Serum HDL-cholesterol concentration was not significantly affected by treatments. Serum IgG concentrations of all copper treatments were significantly lower than that of the control. It was concluded that Cu-chelates supplemented to the basal diet (136ppm Cu) by the level of 100ppm Cu did not significantly affect growth performance of weaning pigs. However, serum parameters of cholesterol, cholesterol and IgG were significantly affected by the treatments.

• Korean Journal of Microbiology
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• v.25 no.3
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• pp.249-253
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• 1987

Effects of Ac pulse at low voltage on Saccharomyces cerevisiae were studied. The treatment of yeast suspensions contained 0.2m NaCl with 500mA for 350 sec at $40^{\circ}C$ was shown about 50% of lethality, whereas in the treatment of the same suspensions with 250mA for 250 sec at the temperature ($10^{\circ}C$) corresponding to about 10% of lethality, growth was completely inhibited instead of lethality. The effect of growth inhibition was due to occurrence of auxotrophic strains under experimental conditions. Detection of auxotrophic yeasts was done tentatively with the difference of the number of viable yeast cells between direct counting by methylene blue staining and plate-count on yeast morphology agar.