• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.630-636
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• 1992

Hansenula nonfermentans KYP-l was selected and identified from 19 methanol utilizing yeasts isolated from soil samples by the enrichment culture technique. This strain showed a high cell concentration and a high aldehyde production. Aldehyde production was carried out in a resting cell system using methanol utilizing yeast as a biocatalyst. The molar yield of acetaldehyde was the highest among the aldehyde investigated, and the maximum amount of aldehyde was produced by cells obtained from a 40 hours' culture.

• Culinary science and hospitality research
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• v.9 no.3
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• pp.130-140
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• 2003

The studies were carried out to optimize a new starter for bread fermentation. Two strains of lactic acid bacteria and yeast were isolated from Kimchi. These strains showed good condition for quality bread fermented. The strains identified as Leuconostoc mesenteroides, Lactobacillus brevis, Saccharomyces fermentati and Saccharomyces cerevisiae. The mixed culture of four strains was due to the synergistic effect by interaction of these strains.

• Journal of the Korean Society of Food Culture
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• v.23 no.2
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• pp.228-234
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• 2008

In this study, Astragalus membranaceus powder was added (3, 6, 9%) during yeast bread preparation and its effect on product quality was examined. The results showed that the dough pH increased as the Astragalus membranaceus powder content increased. However, dough volume during fermentation did not differ significantly among the samples. Bread volume decreased (p<0.001) with an increasing amount of Astragalus membranaceus powder. Also, as the Astragalus membranaceus powder content increased, the Hunter’s color ‘L’ value of the crust decreased and the ‘a’ value increased, and for the crumb, the ‘L’ value decreased and the ‘a’ value increased. Textural property analysis indicated that hardness increased with an increasing amount of Astragalus membranaceus powder. However, up to the 6% level, there were no sensory attribute differences among the samples.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.683-688
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• 1998

This study was conducted to develop optimal composition of flour brew in order to economically utilize flour brew inoculated by lactic acid bacteria as a starter(mother sponge) in bread-making. Two flour brews were prepared ; one with flour and water, the other with flour, water and NaCl. Various nutrients were added to both flour brews and Lactobacilli deMan Rogosa and Sharpe (MRS) broth to investigate the effect of them on growth and activities of Streptococcus thermophilus, Lactobacillus brevis and their mixed culture in flour brews to be tested with incubation at 37$^{\circ}C$. The growth of Streptococcus thermophilus, Lactobacillus brevis and their mixed culture was stimulated by addition of NaCl with 0.85% concentratin and more by mixed culture than by single lactic acid bacteria, resulting in 3 hrs reduction in cultivation and more by mixed culture than by single lactic acid bacteria, resulting in 3 hrs reduction in cultivation time. the addition of 3% glucose to flour brew with NaCl was observed to enhance acid productioni by mixed culture. Yeast extract greatly affected growth and activities of mixed culture of lactic acid bacteria in flour brew with NaCl and its optimum level of this additive in flour brew with NaCl was approximately 1.0%. The optimal composition of flour brew for mixed culture of lactic acid bacteria was suggested as follows; flour 100g, water 300g, NaCl 3.46g, glucose 12.48g, yeast extract 3.46g.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.482-487
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• 2000

Optimization of submerged culture conditions for the production of exo-biopolymer from Paecilomyces japonica ws studied. Maltose, yeast extract, and potassium phosphate were the most suitable sources of carbon, nitrogen, and inorganic salt, respectively, for both production of the exo-biopolymer and mycelial growth. The optimal culture conditions in a flask culture were pH 5.0, $25^{\circ}C$, and 150 rpm in a medium containing (as in g/l) 30 maltose, 6 yeast extruct, 2 polypeptone, $0.5{\;}K_3HPO_4,{\;}0.2{\;}KH_2PO_4,{\;}0.2{\;}MnSO_4{\cdot}5H_2O,{\;}0.2{\;}MgSO_4{\cdot}7H_2O$. Exo-biopolymer production and mycelial growth in the above suggested medium were significantly increased in a 2.5-1 jar fermentor, where the maximum biopolymer concentration was 8 g/l. The morphological changes of the mycelium in the submerged culture were observed within pH ranges from 4.0 to 9.0; i.e., growth of the filamentous form was optimal at culture pHs of 5.0 and 6.0, whereas pellet was formed at other pHs.

• 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.

• Archives of Pharmacal Research
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• v.29 no.3
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• pp.249-255
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• 2006

Ability of iron acquisition of pathogenic microorganisms functions as a virulence factor. Candida albicans, a fungal pathogen that requires iron for growth, is susceptible to growth retardation by high-affinity iron binding proteins such as transferrin. Recently, we reported that C. albicans could utilize the heme as a part of heme-containing proteins dissociated by heme oxygenase, CaHMX1. In search of another pathway that C. albicans can use to bypass the growth regulation produced by iron limitation, this present study examined utilization of non-candidal siderophores such as Desferal and rhodotorulic acid (RA) for acquisition of inorganic iron by the fungus. C. albicans secreting no siderophores was cultured in iron-free (pretreated with apotransferrin for 24 h) (culture medium). Once growth of the yeast reached stasis from iron starvation, a siderophore was added to the culture media. Results showed that cultures containing apotransferrin within a dialysis membrane recovered growth to the level of untreated controls, whereas C. albicans yeast cells in direct contact with soluble iron-free (apo) transferrin recovered growth only partially. When static growth from iron limitation was reached, the addition of siderophore-apotransferrin complex to culture medium also permitted the yeast to recover growth from apotransferrin growth regulation. All the data show that C. albicans can utilize the non-candidal siderophores for iron acquisition under transferrin regulation as can pathogenic bacteria.

• 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).

• Journal of Life Science
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• v.13 no.4
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• pp.492-497
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• 2003

This study was carried out to get the basic data for the mycelial growth of Lentinus lepideus in liquid culture. The optimal temperature and initial pH of mycelial growth of Lentinus lepideus were $25^{\circ}C$ and pH 5.5, respectively. The optimal medium was YMG medium. Among the carbon sources tested, glucose was effected to the mycelial growth and optimal glucose concentration was 4% (w/v). As nitrogen sources, malt extract and yeast extract appeared to be favorable and optimal malt extract and yeast extract [ratio (w/w) of 1:1] concentration was 1.5% (w/v).

• Journal of Microbiology and Biotechnology
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• v.6 no.2
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• pp.103-109
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• 1996

Mn(II)+succinate decreased the carotenoid formation of the yeast Phaffia rhodozyma, probably by scavenging $O_2$. When duroquinone (DQ), an internal and external $O_2$ generator, was added to medium, P. rhodozyma produced more amount of carotenoids. The increased carotenoid production was destroyed by oxygen radical (OR) scavengers, ascorbate+Cu(II) and dimethylsulfoxide. When sub-lethal concentrations of $H_2O_2$ , an external OR source, and antimycin, an internal OR inducer, were used, the effect of $H_2O_2$ on carotenoid formation and composition was less significant than that of antimycin. Addition of superoxide dismutase, an external OR remover, rescued cells from death caused by the high concentration of DO. In this condition, the yeast culture showed an increase in carotenoid content. Addition of DQ into P. rhodozyma culture in the stationary phase did not increase carotenoid production. Therefore, carotenoid formation was stimulated by internal ORs in the growing yeast. It was probably due to release of catabolite repression on carotenogenesis in the yeast. Aeration was important for carotenoid production but was not as effective as the internal OR producer, DQ.