• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1286-1290
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• 2004

This study was carried out to screen yeasts effective in reducing odor from pig feces. Three isolates from soil and compost sources were selected to treat pig feces. On the basis of morphological and biochemical characteristics, one isolate from compost was Candida rugosa, and two isolates from soil were Candida rugosa and Candida maris. These isolates showed deodorizing activity by reducing the concentration of ${NH}_3$ and R-${NH}_2$. Volatile fatty acids (VFA) are the specific malodorous compounds of pig feces, and the Candida maris from soil showed a 100% reduction of butyric, iso-butyric, and iso-valeric acid in 10% pig slurry medium. However, the Candida rugosa from compost showed a 100% reduction of butyric and iso-butyric acid while that from soil showed a 100% reduction of propionic, butyric acid and iso-valeric acid in the medium. Also, these yeasts were effective in reducing $NH_{4}-N$, soluble-N, and biological oxygen demand (BOD).

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.3
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• pp.119-125
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• 2004

Sugar beet stillages were used as a substrate for the production of single cell protein by a thermotolerant yeast Candida rugosa. 3 Stillage substrates were nutritionally optimized for the better production of yeast biomass and for the reduction of COD. The addition of Phosphorus(P) was required for all stillages, but Nitrogen(N) only when the residual sugar remained. The addition of P increased the biomass production to 23-61%. The addition of N increased the biomass production only a little, but when added together with P increased to 90%. The COD decreased to 26-46% when P was added, but decreased to 85% when P was added together with N.

• Microbiology and Biotechnology Letters
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• v.28 no.4
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• pp.223-227
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• 2000

A novel two-step acetone treatment method was developed to enhance the enantioselectivity of Candida rugosa lipase (CRL) toward the hydrolysis of racemic naproxen methyl ester. The acetone-teated CRL was considerably more enantioselective than the crude CRL, yielding an enantiomeric excess of 98~100%. The crude and acetone-treated CRLs were subjected to anion exchange chromatography, and their chromatography profiles were compared. In consequence, both chromatography profiles were found to be almost identical, resulting in two separate lipase peaks (lipase A and B). The lipase B, which is known to be less enantioselective, was treated with acetone using a two-step treatment method. The enantioselectivity of acetone-treated lipase B was dramatically increased, yielding an enantiomeric excess of 99%.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.207-211
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• 1991

Yeast fermentation at $40^{\circ}C$ was conducted for microbial protein production and COD reduction in three different sugar beet stiIlages by a thermo- and acid-tolerant yeast Candida rugosa isolated from East Africa. The assimilation proceedings of some main components such as protein, carbohydrate, total titrable acids and glycerol in stillages were observed with growth kinetics of the yeast. Most of glycerol and organic acids were rapidly assimilated at the beginning of the fermentation. Protein assimilation was slowly accelerated with the proceeding of fermentation time and its assimilation rate reached only 14.2%-28.4%. Though Candida rugosa was a flocculent yeast, the flocculation characteristics of the yeasts grown in three stillages were different from each other.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.281-287
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• 1993

Rye stillage was adopted as a substrate for the production of yeast biomass by a thermotolerant yeast Candida rugosa isolated from East Africa. In the batch fermentation, the yield of biomass and crude protein reached 4.9-8.4g/l and 2.2-3.5g/l, respectively, the rate of COD reduction was about 20%. Over 90% amount of main components such as glycerol and lactic acid were assimilated, but protein assimilation reached only to 38-45% of the initial content. Crude protein content of the dry yeast biomass produced was 42-47% and sulfur-containing amino acid was revealed as limiting essential amino acid.

• Microbiology and Biotechnology Letters
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• v.28 no.6
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• pp.355-360
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• 2000

A UVmutant of Candida rugosa IF00750 was made and used to convert butYlic acid to D-$\beta$-hydroxybutyric acid(D-$\beta$-HBA). Major regulating factors for D-$\beta$-HBA fennentation were investigated via chemostat analyses. The maximum specific productivity was achieved at a specific growth rate of $0.06h^{-1}$ where the glucose and butyric acid concentrations in the fermentor were 10 g/L and 8.7 g/L. respectively. A fed-batch fennentation was performed with maintenance of the optimum glucose and butyric acid concentrations. The D-$\beta$-HBA concentration after 120 h of cultivation reached 12.4 g/L, which was 4.7 times greater illan the concentration obtained by batch fermentation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.522-525
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• 2006

Biodiesel conversion from soybean oil reached a maximum of 70% at 18 h using immobilized 1,3-specific Rhizopus oryzae lipase alone. Biodiesel conversion failed to reach 20% after 30 h when immobilized nonspecific Candida rugosa lipase alone was used. To increase the biodiesel production yield, a mixture of immobilized 1,3-specific R. oryzae lipase and nonspecific C. rugosa lipase was used. Using this mixture a conversion of greater than 99% at 21 h was attained. When the stability of the immobilized lipases mixture was tested, biodiesel conversion was maintained at over 80% of its original conversion after 10 cycles.

• Journal of Animal Environmental Science
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• v.8 no.1
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• pp.17-24
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• 2002

This study was carried out to isolate and identify the yeasts from the the composts, which were effective to reduce odor of the pig feces, and to investigate their physiological properties. In yeasts, one of 30 isolates was obtained on 10% pig feces extract medium. Judging from the morphological and biochemical characteristics, the CY-10 isolated from the compost were identified as Candida rugosa. This isolated strain showed the deodorizing activity by reducing the concentration of $NH_3$ and R-$NH_2$ than that of the control. The CY-10 had completely utilizing butyric acid and iso-butyric acid including 10% pig slurry of the volatile fatty acids, which are the specific malodorous agents of pig feces. Compared to control, this yeast was found effective for decrease in $NH_4$-N, Soluble-N and BOD, 20%, 12.6%, and 9.82% respectively.

• KSBB Journal
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• v.14 no.2
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• pp.225-229
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• 1999

Enzymatic resolution reactions were investigated using Candida rugosa lipase for the production of potically pure S-(+)-Ketoprofen. When the enzymatic hydroysis (and esterification) of recemic ketoprofen esters (and recemic ketoprofen with alcohol) was investigated comparatively, aqueous media was more specific for S-enantiomer than organic media. In the enzymatic hydrolysis of racemic ketoprofen ethyl ester in aqueous media, optimal temperature and pH for enantioselectivity were $37^{\circ}C$ and 4, respectively. The stereoselectivity of the enzyme was enhanced by adding dialcohols such as ethylene glycol and propylene glycol. The enantiomeric ratio obtained in the 40 %(v/v) ethylene glycol was 2-fold higher than that without the additive. By adding $CH_2Cl_2$, $CHCl_3$ and $CCl_4$ (5%,v/v), the enantioselectivity was reversed. A dramatic increase in the stereoselectivity was achieved using lipase purified by anion exchange chromatography. The type A lipase(the first eluted lipase fraction) showed an enantiomeric ratio of >100, whereas the type B lipase(the second eluted lipase fraction) exhibited enantimomer ratio of 9.0 in the hydrolysis of racemic ketoprofen ethyl ester.

• Journal of Microbiology and Biotechnology
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• v.5 no.2
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• pp.114-116
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• 1995

Concentrated Brazillian sugar cane stillage was used as a substrate for the yeast biomass production using Candida rugosa isolated from East Africa. At the optimum stillage concentration of 10% dry matter, biomass production was 20.4 g/l and COD reduction rate was 41%. The specific growth rate of the yeast was 0.17 $h^{-1}$ and the corresponding productivity 0.91 g $l{-1} h^{-1}$ in the batch fermentation was observed at $40{\circ}^C$.