• The Korean Journal of Mycology
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• v.46 no.4
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• pp.415-425
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• 2018

To study the characteristics of yeasts, 433 strains of the genus Aureobasidium were isolated from the flowers collected from Jeolla-do in Korea, and the diversity of the strains was confirmed through molecular phylogenetic and morphological analyses. Based on phylogenetic analysis of LSU rDNA seguences, the Aureobasidium strains from the Jeolla-do province were classified into six groups. The dominant species of flower-derived yeasts were Groups A and D. Since Groups B, E, and F were found only in Jeollanam-do, we can infer that the Aureobasidium is distributed more widely in Jeollanam-do than in the Jeollabuk-do province. Through LSU and ITS rDNA sequence analyses, Group A was identified as A. pullulans, Group B as A. melanogenum, and Group F as a putative new species of Aureobasidium. Groups C, D, and E do not completely match with A. leucospermi, A. namibiae, or A. subglaciale by LSU or ITS rDNA analysis but are closely related to those species. Comparisons of colony morphology are likely to be more helpful in distinguishing Groups C and D. The results of this study can provide useful characteristics for future studies of the genus Aureobasidium.

• Journal of Veterinary Clinics
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• v.29 no.6
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• pp.464-469
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• 2012

This experiment was applied to examine the effects of ${\beta}$-glucan originated from Aureobasidium on wound healing infected by 3 strains of bacteria in the normal nude mouse. From the results it was suggested that ${\beta}$-glucan has properties, which may be beneficial in the treatment of wound healing though it does not showed any antibacterial activities against wound infections by three strains such as S. aureus, S. pyogenes and P. aeruginosa. Therefore, it is considered that ${\beta}$-glucan will be promised as a new wound management.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.60-62
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• 1996

Aureobasidium pullulans produced three kinds of extracellular polyols e.g. glycerol, mannitol, and sorbitol from either sucrose, glucose, fructose or mannose. Sorbitol was selectively produced when urea was used as a sole nitrogen source, and the amounts of sorbitol produced rapidly reached a plateau after 50 h where its maximum quantity was about 20 g/l with sucrose.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.301-306
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• 1991

Extracellular fructosyl transferase from Aureobasidium pullulans C-23 was characterized. The molecular weight of the isolated enzyme was determined to be approximately 170,000 by SDS polyacrylamide gel electrophoresis. The enzyme has the pI value of about 3.7. The enzyme was almost completely inhibited by 5mM $Hg^{2+}$ , but was not significantly affected by other cations tested. The enzyme was inactivated by treatment of tryptophan-specific reagent N-bromo- succinimide and tyrosine-specific reagent iodine. The substrate sucrose showed protective effect on the inactivation of the enzyme by the both reagents. These results suggest that tryptophan and tyrosine residues are probably located at or near active site of the enzyme.

• Microbiology and Biotechnology Letters
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• v.22 no.6
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• pp.565-570
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• 1994

The pullulan production and morphological change of Aureobasidium pullulans ATCC 9348 were investigated both in batch fermentation and in continuous fermentation. The best carbon source for pullulan production was sucrose among seven different carbon sources. The pullulan production of A. pullulans was increased with increasing the carbon to nitrogen ratio of the medium using sucrose as a carbon source. In batch fermentation, production of pullullan occurred following exhaustion of the nitrogen source from the medium. The continuous fermentation showed that the pullulan production was closely parallelled with cell growth and was most effective at a dilution rate of 0.06~0.07 hr$^{-1}$-. The ratio of yeast-like cells(blastospores) of A. pullulans increased with the increase of growth rate, and reached 100% over the growth rate of 0.07 hr$^{-1}$. The growth rate, within a certain range, affected not only on the cell morphology, but on the specific pullulan productivity of A. pullulans.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.360-366
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• 1987

For the production of pullulan from the high concentration of sugar, the utilization of sugars by a pullulan-producing fungus, Aureobasidium pullulans was examined. A. pullulans showed the different utilization patterns for sugars such as sucrose, maltose, and maltotriose. Especially for maltotriose, the hydrolysis of sugar was accompanied by a transferase activity. Glucose and maltose showed the inhibitory effect on the cell growth and the pullulan production at the sugar concentration higher than 0.28M, but sucrose showed the inhibitory effect at the sugar concentration higher than 0.14M. Among the sugars examined, sucrose gave the best result for the pullulan production. 27.5g/l of pullulan was obtained from 5% sucrose.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.417-422
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• 1990

For optimal production of fructosyl transferase in AureobasidiumpuZZulane C-23, the effect of fermentation conditions for cell growth and fructosyl transferase production were investigated. Sucrose was excellent carbon source. Sucrose concentration for the optimum production of fructosyl transferase was 35%. Enzyme productivity was significantly increased by addition of ammonium oxalate and yeast extract. A time course study for the enzyme production by Aureobasidium pullutans C-23 was carried out. At 2 days incubation, the production of intracellular enzyme was maximum. The extracellular enzyme production was found to be increased up to 6 days.

• KSBB Journal
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• v.9 no.2
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• pp.122-126
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• 1994

A new method for the production of isomalto-oligosaccharides from maltose was investigated using intact cells of Aureobasidium pullulaans which had been known to produce fructo-oligosaccharides. The cells showed transglucosylation activity producing isomalto-oligosaccharides at high concentrations of maltose, while they showed a hydrolytic activity at low concentrations of substrate when cultivated at $25^{\circ}C$. The optimum reaction conditions for the isomalto-oligosaccharide production were as follows: substrate concentration, 500g/l maltose; pH, 4.5; temperature, $65^{\circ}C$; cell dosage, 10 unit per gram substrate. Under optimized conditions, the maximum yield of isomalto-oligosaccharides achieved was around 48% (w/w). At the early period of reaction, panose was selectively produced from maltose, and thereafter isomaltotriose was synthesized by utilizing panose as a substrate when maltose consumption was discontinued.

• The Korean Journal of Mycology
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• v.46 no.3
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• pp.307-314
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• 2018

The goal of this study was to investigate the microbiological characteristics of the ethanol-producing wild yeast, Aureobasidium pullulans P-1, isolated from flowers growing near the Yedang reservoir, Chungnam province, Korea, and in addition, to optimize its fermentation ability for the production of Makgeolli. A. pullulans P-1 was oval-shaped, and formed ascospores and pseudomycelium. The P-1 strain was a halophilic and sugar tolerant yeast which grew in 15% NaCl and 50% glucose-containing yeast extract-peptone-dextrose media. The P-1 strain was also resistant to 20% ethanol. Changes of the physicochemical properties during Makgeolli fermentation by A. pullulans P-1 were investigated. A maximum of 8.45% ethanol was obtained when a mixture of cooked rice, 150% water, and 35% ipguk per cooked rice was fermented by 5% A. pullulans P-1 culture broth at $25^{\circ}C$ for 10 days. Antihypertensive angiotensin I-converting enzyme inhibitory activity in the Makgeolli ferment produced by A. pullulans P-1 reached a high of 71.1% after 10 days.

• KSBB Journal
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• v.11 no.4
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• pp.497-503
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• 1996

In this study, the effects of nitrogen sources and pH on pullulan production were investigated. As a result, the best nitrogen source in pullulan production by Aureobasidium pullulans was shown to be peptone and its product yield was 62%. Optimum concentration of carbon/nitrogen source ratio was 50/0.15 and the production of pullulan was inhibited at ratios higher than 50/0.15. Aureobasidium pullulans had produced 29.1, 27.4 and 26.5 g/L pullulan, respectively in media I, II, and III containing mixed nitrogen sources. This result showed that pullulan could be produced efficiently from mixed nitrogen source. It was found that pullulan yield with pH control was higher than that with no pH control. In fedbatch fermentation, pullulan yield obtained with a feeding rate of 0.05 N-g/L for nitrogen source was higher than that without nitrogen source feeding.