• Microbiology and Biotechnology Letters
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• v.7 no.4
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• pp.191-195
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• 1979

This study was conducted to investigate the effect of saccharified extract of ginseng meal on alcohol fermentation and reproduction of yeast. Different concentrations of saccharified extract of ginseng meal in liquid medium were tested, and the experimental results obtained were summarized as follows : 1. In the process of alcohol fermentation of yeast, $CO_2$ output was much accelerated by the higher concentration of saccharied extracts from 1％ to 6％, but $CO_2$ output was disurbed at the concentrations of 10％ and 15％. .2. In the process of alcohol fermentation of yeast, the production of alcohol was increased by the higher concentration of saccharified extracts from 1％ to 6％, but decreased at the concentrations of 10％ and 15％. 3. Number of reproduced yeast cell after aerobic culture of Sacc. cervisiae was increased by the higher concentration of saccharified extracts from 1％ to 10％, but decreased at the concentration of 15％. The number of yeast cell at the concentratin of 10％ extract was 1.6 times more than that of control.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.331-336
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• 1998

The possibility of using waste brine from kimchi factory as a substrate for the production of the single cell protein was investigated. The growth of Pichia guilliermondii A9 isolated from waste brine was not inhibited by the NaCl up to 10% (w/v). BOD of the waste brine was reduced to one tenth after 24 hours of yeast culture. The addition of ammonium salt, phosphate, and micronutrients to the waste brine did not enhance the growth of P. guilliermondii A9. However, when the brine was enriched with juice from waste cabbage, the final cell mass increased proportionally with the amount of added organic material, suggesting a practical application for the treatment of two different types of waste produced during kimchi manufacturing.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.867-872
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• 2002

This study was performed to investigate the optimum process conditions for manufacturing yeast extract from waste brewer's yeast using various enzymes. Contents of IMP, GMP, free amino acids, and crude protein of yeast extracts were measured by enzymes treatment. Crude protein contents of yeast extracts subjected to cell wall digestion enzyme treatment were 21.1, 33.6, and 28.0% for the control grouup, glucanase (0.5%, 12 h), and tunicase (1%, 18 h), respectively. Crude protein contents of yeast extracts subjected to protease treatment were 22.0, 30.8, and 29.8% for control group, bromelin (1%, 3 h), and protamex (1%, 3 h), respectively. Crude protein content of yeast extract subjected to glucanase and protamex mixed treatment was 34.4%. The total contents of IMP and GMP of yeast extracts subjected to G+P+A (glucanase+phosphodiesterase+adenyldeminase) and G+Pro+P+A (glucanase+protamex+phosphodiesterase+adenyldeaminase) treatments were 1,066 and 1,047 mg/100 g, respectively. The content of free amino acids of yeast extract was the highest (2,302 mg/100 g) in G+Pro+P+A treatment. Optimum concentration and process condition of enzyme treatment to obtain yeast extract with high IMP, GMP, and free amino acid content were in the order of glucanase (0.5%, 12 h), protamex (1%, 3h), phosphodiesterase (0.1%, 3 h) and adenyldeaminase (1%, 1.5 h) treatments.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2001.05b
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• pp.121-125
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• 2001

For the probiotic feed production, aerobic liquid fermentation of pulverized food wastes was attempted with a yeast Kluyveromyces marxianus. After grinding finely, optimal fermentation conditions of the substrate was investigated by shaking culture. The most active growth of the yeast was shown at solid content of 10%. The proper addition of urea(0.5g/l), o-phosphate(0.4g/l), molasses(4g/l), and yeast extract (1g/1) increased cell growth rate and viable cell count. For optimizing, the nutrients were all added to substrate and fermentation was carried in 2 litre jar fermenter. For the stimulation of hydrolyzing enzyme excretion, mixed culture with Aspersillus oryzae was also conducted. In 12 hours of fermentation, viable cell count of the yeast Kluyveromyces marxianus amounted to the number of 1.4 $\times$10$^{10}$ /1 in the culture medium.

• The Korean Journal of Mycology
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• v.23 no.4 s.75
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• pp.354-358
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• 1995

A yeast loading biochemical oxygen demand (BOD) sensor was designed and constructed to quickly measure the concentration of biologically assimilable organic substances dissolved in water as BOD values to feed back to the waste water treating processes. The sensitivity of the BOD sensor reached maximum at around pH 7.0 and $30^{\circ}C$ where yeast showed the highest assimilation activity. Biomass also affected the sensor output, and biomass of $ 0.14\;mg/cm^2$ on the dialysis membrane appeared to be the optimum cell mass level. The sensitivity of the sensor depended on the kinds of pollutants and increased considerably when the yeast was preincubated in the solution of respective pollutants before loading on the sensor.

• Journal of Animal Environmental Science
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• v.6 no.3
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• pp.201-209
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• 2000

Optimal conditions to utilize egg type male chicks from hatchery for cultivating yeast(Saccharomyces cerevisiae) and the effects of the yeast culture on growth of broiler chicks were investigated. The protein concentration of the spent cockerel extracts was the highest when extracted for 72 hours. Optimal water volume added to the spent cockerel chicks for the extraction was 1.5 times to the cockerel chicks weight (v/w ratio). Lipid in the extracts from the spent cockerel chicks did not affect on the yeast growth. The number of yeast cultured in the SCELP2 medium containing spent cockerel extracts and 4 % sugarcane molasses was higher by 26 % than that in the YEPD medium containing 1 % yeast extract, 2 % bacto pepton and 2 % glucose. Also the number of yeast cultured in the SBYW2 medium containing SCEP2 medium containing SCELP2 and 4 % brewer's yeast waste was increased by 8 %, compared to that in the SCELP2 medium. Body weight gain of chicks fed 4 % yeast culture supplementations cultivated in the SBYW2 medium was increased at 5 weeks by 9 %, relative to no supplementation(P<0.05). The results from this study suggest that the spent cockerel chicks can be utilized as nitrogen sources to produce yeast culture for animal feed.

• Journal of Microbiology and Biotechnology
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• v.19 no.10
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• pp.1161-1168
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• 2009

Ethanol production by the simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% raw starch. For the SSF, the RWC slurry was mixed with the raw-starch-digesting enzyme of Rhizopus sp. and yeast, where the yeast strain was selected from 300 strains and identified as Saccharomyces cerevisiae KV25. The highest efficiency (94%) of ethanol production was achieved when the uncooked RWC slurry contained 23.03% starch. The optimal SSF conditions were determined as 1.125 units of the raw-starch-digesting enzyme per gram of RWC, a fermentation temperature of $30^{\circ}C$, slurry pH of 4.5, 36-h-old seeding culture, initial yeast cell number of $2{\times}10^7$ per ml of slurry, 17 mM of urea as the nitrogen additive, 0.25 mM of $Cu^{2+}$ as the metal ion additive, and a fermentation time of 90 h. Under these optimal conditions, the ethanol production resulting from the SSF of the uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.177-182
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• 2016

Malodor emitted while producing fertilizer from hatchery egg waste treated with microorganism is an important limiting factor. To reduce this problem, we attempted to use two yeast strains, Saccharomyces cerevisiae, KACC 30008 and KACC 30068. Both yeast strains reduce ammonia gas emission 35.4% than only treated with bacterium, Bacillus amyloliquefaciens. When both strains were used together, that was reduced as 57.1%. KACC 30008 and 30068 strains reduced hydrogen sulfide 42 and 90.4%, respectively. Both strains together reduced hydrogen sulfide gas as 98.5%. KACC 30008 did not decrease methyl mercaptan emission. However KACC 30068 decreased 40% and both strains together decreased the gas emission as 66.7%. Overall, this study showed that yeast treatment could enhance the effect of B. amyloliquefaciens treatment in the reduction of malodorous gas emission.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.1
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• pp.1-11
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• 1996

The effect of seeding on the thermophilic composting of food waste was investigated with selected strains of yeast, thermophilic bacteria and the mixed strains of yeast and bacteria in the lab-scale composter at $50^{\circ}C$. The results demonstrated that in all case the growth of yeasts preceded the growth of thermophilic bacteria by one or two days. The seeding of bacteria alone was ineffective for thermophilic bacterial development and the rapid increase of total thermophilic bacterial count was obtained by mixed seeding of yeasts and bacteria. Moreover, the bacterial growth was accelerated by the addition of yeasts alone. It was revealed that the yeasts removed organic acids from the food waste at the initial period and consequently induced the growth of thermophilic bacteria. The results presented in this paper indicate the indispensable role of yeasts for thermophilic process of food waste composting.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.97-103
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• 2012

Suspended wood waste was being inflow into the dam and the problem of waste disposal has been occurred. In this study, ethanol production using woody floater wastes was performed to estimate value in use for raw material of renewable energy. To achieve the goal, experiments of acid hydrolysis and ethanol fermentation using dam woody floater as raw materials for bioethanol was carried out. In the results of field survey in the chungju dam, kind of woody floater was mainly Japanese larch (Larix leptolepis) and hybrid poplar (Populus tomentiglandulosa). The results of sugar extraction showed that sugar content was higher in Larix leptolepis than Populus tomentiglandulosa. Extracted sugar from wood waste was effective consumed by yeast(P. Stipitis and S cerevisiae). In the experiment consumption of sugar including glucose, galactose and xylose, the consumption rate of S. cerevisiae is faster than that of P. stipitis. and efficiency for ethanol production is higer in S. cerevisiae than P. stipitis. Also it can be confirmed that resource as ethanol production using wood waste was available.