• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.105-110
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• 1988

The production of single cell protein using the amylolytic fusant obtained from cell fusion between Hansenula anomala and Saccharomyces cerevisiae was studied. The fusant12 strain was selected for single cell protein production from starchy materials among five fusants. Optimum nitrogen source and its concentration for the growth of fusant12 were ammonium sulfate and 0.1%, respectively. Optimum concentration of soluble starch and optimum pH of the basal medium were lord and pH 5.6, respectively. Autolysis of fusant12 was effectively carried out by addition of 5% (v/v) ethyl acetate to the cell suspension and liquidization for 30 min before incubation for 24 hr at 3$0^{\circ}C$. Coculture of fusant12 and non-amylolytic yeast, Torulopsis candida YA-l5, resulted in the increase of the mass as compared to the monoculture of fusant12. The cell mass on tapioca medium was increased about 2.5 times as on soluble starch medium. The content of crude protein and nucleic acid of the dry cell were 39% and 5.8%, respectively.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.55-59
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• 2006

This study was designed to investigate the optimum manufacturing condition of germanium-fortified yeast, and the binding properties of germanium (Ge) in germanium-fortified yeast. The nutritional optimum conditions were glucose 3.0 (w/v) %, yeast extracts 0.3 (w/v) % and peptone 0.5 (w/v) %, and the amounts of yeast cells were 67.4 mg/ml. And, the standard germanium-fortified yeast was produced under the condition at the ratio of yeast cell and germanium solution was 1 : 0.5 (50%), pH 6.5 and $35-40^{\circ}C$ during fermentation. In results of the identification, binding of germanium-protein showed structural difference between the inorganic Ge $(GeO_2)$ added during fermentation process and germanium-fortified yeast. Therefore, germanium-fortified yeast made by biosynthetic technology formed structurally safe organic germanium during fermentation process. Germanium-fortified yeast can be applied as a new functional material far the improvement of health, the prevention and treatment of chronic degenerative disease like cancer, and the enforcement of immune system.

• KSBB Journal
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• v.19 no.4
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• pp.291-294
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• 2004

The aim of this study was to figure out the antibacterial pattern of leucocin A transformed yeast with culture. Dry cell weight, total secreted protein, and antibacterial activity were increased to 12 hour, after then they showed decrease while protease activity represented the opposite pattern. This implied the production of leucocin A was growth-related. Compared to the result of one hour culture broth, antibacterial activity was about 3.24 fold at 12 hour culture. Maximum growth inhibition rate was 70.57% compared to nontransformed yeast. As the increase of protease in the supernatant, the antibacterial activity was diminished. This study could permit the mass production of bacteriocin to use as antibiotics or food preservatives.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.219-228
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• 2003

Two experiments were conducted to investigate the influence of dietary supplementation of yeast culture on the nutrient digestibility, performance and meat quality in growing-finishing pigs. Corn-soy basal diets contained 20, 18, and 16% CP and 3,265kcal/kg ME at different growth stages. One hundred and twenty pigs(8wk-old) were allocated into four supplementation levels of yest culture (0, 0.1, 0.2, 0.4%) in Expt 1. Weight gain, feed intake and feed efficiency were periodically recorded for 112 days. A metabolic feeding trial was conducted to measure the nutrient digestibility. Physical and chemical characteristics of the Longissimus Dorsi muscle(LM) from the pigs were measured at the end of experiment (Expt 2). In Expt 1, weight gain and feed efficiency were not different among the dietary treatment groups during the overall period. The digestibilities of protein and fiber were greater in 0.1% and 0.2% yeast culture-supplemented groups than in control (P<0.05). However, fat and ash digestibilities were not improved by the dietary treatment. In Expt 2, the LM protein content in 0.1% yeast culture-supplemented group, but not in 0.2% or 0.4%-supplemented group, was greater than that in the control group (P<0.05). The LM pH, purge loss, cooking loss and color were not affected by the dietary treatment. The LM shearing force was less in 0.2% yeast culture-supplemented group than in the control group (P<0.05). Other LM physicochemical properties did not differ between the dietary treatment groups. Total saturated and unsaturated fatty acids percentages and total cholesterol content of the LM did not differ across the dietary treatment groups.

• Korean Journal of Poultry Science
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• v.29 no.2
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• pp.109-116
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• 2002

The objective of this study was to investigate the effect of feeding organic acid mixture and yeast culture on the Performance and e99 quality of laying hens fur sixteen weeks. Four hundred and fifty 19-wk-old ISA Brown layers were alloted to five treatments with five replications of each. The supplemental levels of organic acid mixture(OAM) and yeast culture(YC) in the experimental diets were 0(control), OAM 0.1, 0.2%, and YC 0.1, 0.2%, respectively. Corn -Soy basal diet containing 16.0% CP and ME 2,770 kca1/kg ME. Eggs were collected and weighed every day. Eg3 Production, fred intake and fled conversion were recorded in every four weeks. Fatty acid composition of e99 Yolk, e99she11 breaking strength, thickness and Haugh unit were measured a(her every eight weeks. Egg Production and daily egg mass of birds fed 0.2% OAM and 0.1% YC tended to be higher than those of the other treatment groups. Egg weight was the highest in hens fed with 0.2% OAM treatment, but was not significantly different. Feed conversion of hens in all OAM and YC treatments was lower than those of control, but was not statistically different. Eggshell breaking strength of hens on OAM treatments tended to be higher than those of YC treatment and control. Haugh units of the birds fed OAM was significantly higher than controls (P<0.05). 599 yolk color score of OAM treatment was higher than those of YC treatments and control, but the difference was not significant. At 27-wk-old, arachidonnic acid content in eggs from the birds fed 0.1% OAM diet was significantly higher(P<0.05) than controls. The results of this experiment indicated that dietary organic acid mixture and yeast culture tended to improve the egg Production and internal egg quality.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.199-205
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• 2005

Physicochemical quality characteristics of seed mashes were investigated for development of new creative breadmaking in bakery. Aridity of seed mashes fermented with Koji, lactic acid bacteria, and baker's yeast was slightly lower than those fermented with Koji and yeast. ${\alpha}-Amylase$, saccharifying amylase, and acidic protease activities of seed mash composed of water (560 mL) and Koji (400 g) were 0.26 SKB, 36 SP, and 645 HUT/g, respectively. Reducing sugar content of seed mash made with Koji increased up to 13.04% after 36 hr fermentation, then decreased drastically thereafter, whereas that of seed mashes made with Koji, yeast, and lactic acid bacteria increased up to 6.5% at 6 hr, decreased to 1 to 2.5% at 12 hr, and remained less than 0.7% after 18 hr fermentation. Total organic acid contents were 10.4-12.25mg/mL. Flavor compounds including ethyl acetate, ethyl caprylate, isoamyl acetate, and p-vinyl guaiacol were detected in seed mash fermented with Koji, yeast, and L. brevis. These results show use of seed mash fermented with Koji, S. cerevisiae, and lactic acid bacteria enhances bread flavor.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.147-152
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• 2000

For the probiotic feed production from residual food waste by using the yeast Kluyveromyces marxianus, aerobic liquid fermentation was attempted at $35^{\circ}C$. After grinding finely, optimal fermentation conditions of the substrate was investigated in shaking incubator. By controlling water content yeast growth was studied at each different solid content of 5, 10 and 15% respectively. The most active growth of the yeast was shown at 10%. For the stimulation of the cell growth, mixed culture with Aspersillus oryzae was conducted in a 2 litre-jar fermenter. As the results, the yeast growth rate was increased, but the maximum viable cell count amounted was slightly higher as $3.5{\times}10^9/ml$ than single culture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.15 no.4
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• pp.24-31
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• 1986

A methanol-assimilating yeast for the production of Single Cell Protein was isolated from the soil and identified. Methanol as a sole carbon source was used in this study. The strain was identified as Candida boidinii which grew best at the initial concentration of methanol at 2% , with the addition of 0.5% methanol at every 12 hours, The Single Cell Protein production was maximal after 72 hours of incubation at pH 5.0, $30^{\circ}C$. Thiamin and biotin were stimulated the growth of this yeast at the levels of $1000{\mu}g/{\ell}$ and $10{\mu}g/{\ell}$respectively.

• The Korean Journal of Mycology
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• v.39 no.3
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• pp.227-228
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• 2011

Fibrinolytic activities of culture concentrates of various yeasts were investigated. The concentrates of the culture broth of Saccharomyces cerevisiae Y99-7 showed the strongest fibrinolytic activity of 25 mm (clear zone). The fibrinolytic activity of Saccharomyces cerevisiae Y99-7 was more high in the culture concentrates from PD broth rather than that of yeast extract-peptone dextrose cultures (clear zone : 22.7 mm).

• Food Science and Preservation
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• v.6 no.2
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• pp.221-227
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• 1999

The immobilized culture system of Saccharomyces cerevisiae was examined to improve the efficiency of vinegar production from persimmon juice. Optimum concentration of Na-alginate for the immobilization was 2%. When the 1eakage of yeast from get beads was checked by turbidity of culture medium with varying concentration of Na-alginate from 1 to 4%, turbidity of culture medium increased from 8 hrs of cultivation with 1% Na-alginate concentration showing optical density of 0.82 at 20 hrs. However, the increase in turbidity of culture medium was slow with 2-4% Na-alginate showing optical density of 0.55-0.58 at 20 hrs. Microscopical analysis of gel matrix showed that the immobilized yeast was grown well regardless of Na-alginate concentration. Optimum size of gel bead and amount of inoculation were 2-3 m and 33mg, respectively. For ethanol production aerobic cultivation for 121hrs using cohen plug followed by anaerobic cultivation using silicon plug equipped with a check valve was the most effective.