• 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.

• 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.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.21-25
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• 1997

A study on the removal of mercury by Saccharomyces cerevisiae and Aureobasidium pullulans was done, in which the model of adsorption isotherm and adsorption rate was proposed. The adsorption isotherm of mercury by S. cerevisiae was accorded with Langmuir model but A. pullulans was followed to Freundlich model. The amount of mercury removed by A. pullulans was higher than that of S. cerevisiae, but the adsorption rate of mercury by A. pullulans was slower than that of S. cerevisiae. In a rapid adsorption process, therefore, it is more useful to use S. cerevisiae as a biosobent.

• 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.

• 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.21 no.5
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• pp.494-503
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• 1993

A fungal strain was isolated as a pullulan-producer from plant leaves and identified as Aureobasidium pullulan GM21. With A. pullulans GM21, culture conditions were optimized for the pullulan production and the changes of the molecular weight of pullulan produced were investigated according to the culture conditions we obtained maximum conversion yield of pullulan about 58-60%(40.8-42.0g/l) from 7% sucrose at 25C, initial pH 7.5 by the batch cultivations either in Erlenmeyer flask or in jar fermentor.

• Journal of Life Science
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• v.11 no.2
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• pp.116-119
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• 2001

Xinlei studies on the production of pullulan by Aureobasidium pullulans using batch culture in a 15L bioreactor were carried out. The mathematical models were obtained in this study, which provided a reasonable description for the biomass, the product, and the substrate variation with time. The values frets the mathematical models were satisfactorily coincided with the experimental data for the biomass of A. pullulans, the production of pullulan and the utilization of sucrose as the sole carbon source.

• The Korean Journal of Mycology
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• v.50 no.4
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• pp.331-341
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• 2022

This study was conducted to identify yeast species isolated from domestic pear blossom through gene sequencing and analysis of morphological characteristics, and to confirm specific yeast species inhibitory effects toward fire blight in immature apples, pears, and crab apple blossoms. Yeast morphological characteristics were consistent with the known characteristics of Aureobasidium pullulans. Nucleotide sequencing of the D1/D2 region of large-subunit (LSU) 26S ribosomal DNA and the internal transcribed spacer (ITS) region confirmed its identity as A. pullulans (MHAU2101). Inoculation of immature fruits with A. pullulans MHAU2101 before exposure to Erwinia amylovora prevented fire blight symptoms in apples and pears. A. pullulans MHAU2101 treated crab apple blossoms had a significantly lower flower infection rate than untreated blossoms, revealing 64% of the potency of streptomycin. The A. pullulans MHAU2101 treated group also displayed lower E. amylovora density in both pistil and hypanthium compared to the untreated group, especially in the hypanthium. This study confirms that A. pullulans MHAU2101 isolated from domestic pear blossom can effectively suppress the onset of fire blight.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.1049-1053
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• 2007

Tannase production by Aureobasidium pullulans DBS66 was optimized. The organism produced maximum tannase in the presence of 1% tannic acid after 36 h. Maximum gallic acid accumulation was observed within 36 h and tannic acid in the fermented broth was completely degraded after 42 h of growth. Glucose had a stimulatory effect on tannase synthesis at 0.1% (w/v) concentration. The organism showed maximum tannase production with $(NH_4)_2HPO_4$ as nitrogen source. Shaking speed of 120 rpm and 50-ml broth volume have been found to be suitable for maximum tannase production.