• KSBB Journal
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• v.5 no.2
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• pp.101-106
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• 1990

The aspects of pullulan production by Aureobasidium pullulans were investigated under various initial pH, carbon source and nitrogen source conditions. The resulting pullulan fermentation broths were analyzed by using GC, LC and GPC techniques. The maximum pullulan production was obtained in the culture medium containing 5% sucrose at pH 6, 28$^{\circ}C$ after 7 days of cultivation. Under the pH 3, pullulan was almost not produced although the total cell mass of A. pullulans was increased, and the case on using (NH4)SO4 as a nitrogen source, which usually cause the fermentation medium under pH 3, also gave the similar phenomena. Sucrose was believed to converted to trisaccharide and glucose extracellulary and polymerization of glucose was proceeded intracellulary.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.149-154
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• 2015

BACKGROUND: Yeast isolates associated with the leaves, stems, and flowers of the tiger lily needed to be identified using isolation methods that have previously been used effectively in yeast biotechnology. A culture-based approach was necessary for the isolation of many yeast strains associated with tiger lily. METHODS AND RESULTS: In this study, the homogenized leaves, stems, and flowers of tiger lily were spreaded onto GPY medium containing chloramphenicol, streptomycin, Triton X-100, and L-sorbose. A total of 82 yeast strains from the leaves, 94 and 97 yeast strains from the stems and flowers were isolated, respectively. Yeast isolates were identified by phylogenetic analysis based on internal transcribed spacer region sequencing. The yeast species isolated from the leaves comprised of 31 isolates of the genus Pseudozyma, 28 of Aureobasidium pullulans, and 11 of the genus Cryptococcus. Those isolated from the stems comprised of 40 of A. pullulans and 11 of Cryptococcus, and 95 of A. pullulans While, 1 isolate each of the genera Rhodotorula and Metschnikowia were isolated from the flowers. CONCLUSION: We identified site-specific yeast communities associated with tiger lily. These yeast isolates may have high potential for application in the field of biotechnology.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.1
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• pp.1-9
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• 2020

In this experiment, the Grateloupia elliptica (G. elliptica) was fermented using the fungus Aureobasidium pullulans (A. pullulans) and its extract was obtained from hot water and 70% ethanol solution. The extract was studied for their biological activities such as antioxidant effect, Collagenase and tyrosinase inhibition in comparison to the nonfermented exatract in same solvents. Antioxidative activity test using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) showed that ethanol extract had higher antioxidant activity than water extract. Among all of the samples, the antioxidant activity of G. elliptica fermented ethanol extracts (GEFEE) was highest. Tyrosinase inhibitory activity of GEFEE was highest with 9.8% at the 1,000 ㎍/mL concentration. No inhibition of collagenase from G. elliptica water extract (GEWE) and G. elliptica fermented water extract (GEFWE) was observed, but G. elliptica ethanol extracts (GEEE) and GEFEE showed increased collagenase inhibition activity with increasing concentrations of them. Collagenase inhibitory activity of GEFEE was highest with 50.3% at the 1,000 ㎍/mL concentration. MTS cell proliferation assay was conducted with the GEWE, GEEE, GEFWE, GEFEE and cell viability was over 90% at the 10 ㎍/mL ~ 1000 ㎍/mL concentrations for all of the samples, which suggested that the extracts were noncytotoxic. In conclusion, fermented extracts of G. elliptica could be developed to bioactive functional material for cosmetics with antioxidant and wrinkle improvement effects.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.312-316
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• 2018

BACKGROUND: Yeast biotechnology finds applications in various industries. Hence, we sought to explore the yeasts associated with the flower of Aster spathulifolius Maxim. This study aimed to isolate yeasts from the flower of the plant and screen for biosurfactant-producing yeasts. METHODS AND RESULTS: We collected flowers of Aster spathulifolius Maxim. and performed pure isolation using four types of media. In total, 117 strains belonging to 4 genera, namely, Cryptococcus (75 strains), Aureobasidium pullulans (30 strains), Candida (11 strains), and Rhodotorula (1 strain), were isolated and identified by ITS sequencing. Upon in-depth analysis, Cryptococcus, the most dominant genus (75 strains) was categorized into the 'Unknown group'. Upon in-depth analysis of A. pullulans, we discovered the 'Unknown group I' (27 strains) and the 'Unknown group II' (2 strains), which have not been reported previously. Two A. pullulans isolates with potent surfactant activity were selected via the screening procedure. CONCLUSION: In this study, a total of 117 strains were isolated from the flower of Aster spathulifolius Maxim. In addition, two biosurfactant-producing yeasts were identified from among the isolated yeasts.

• 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.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.253-256
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• 2003

In batch culture of A. pullulans HP-2001, maximal production of pullulan was 57.90 g/l at 96 hr. The maximal production of pullulan with 76.55 g/l occurred when substituted solution was 10% (w/v) sucrose, 0.25% (w/v) yeast extract and mineral salts. The maximal production of pullulan was 75.00 g/l with a dilution rate of $0.015\;h^{-1}$. Productivity of pullulan in the continuous culture fed with the fresh medium was higher than that fed with the fresh medium without nitrogen source.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.325-328
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• 2000

The effects of DO and pH on the mass production of pullulan with high-molecular weight from A. pullulans ATCC 42023 were evaluated. The maximum pullulan production yield (51%) was obtained at pH non control (initial pH 6.5) and DO control (above 50%) condition. The pullulan degrading enzyme was activated when the pH of broth reached lower than 5.0 and portion of low molecular weight pullulan was increased. The formation of a black pigment was observed at the initial stationary phase, 40hr of fermentation. Therefore, the fermentation should be carried out in pH non control and DO control condition and harvested before reaching stationary phase around 40h for the production of high molecular weight pullulan.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.238-243
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• 2015

BACKGROUND: Yeasts associated with fleabane flowers were identified using isolation methods previously applied in yeast biotechnology. A culture-based approach was required for isolation of many yeast strains associated with fleabane. METHODS AND RESULTS: We spread homogenized fleabane flowers onto GPY medium containing chloramphenicol, streptomycin, Triton X-100, and L-sorbose. We isolated 79 yeast strains from the flowers of wild fleabane, and identified the yeasts via phylogenetic analysis of isolates from agar plates. The yeast species included 39 isolates of Aureobasidium pullulans, 17 of the genus Candida, 14 of the genus Rhodosporidium, 6 of the genus Cryptococcus, and 3 of the genus Rhodotorula. CONCLUSION: Yeast isolates associated with fleabane flowers included A. pullulans (39 isolates) and other yeast species (40 isolates). Such yeast isolates may have biotechnological potential.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.315-324
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• 2010

The effect of beta-glucan ($Polycan^{TM}$) derived from Aureobasidium pullulans SM-2001 were observed on, collagen-induced rheumatoid arthritis (RA) in DBA mice. Six week-old male DBA/1J mice were immunized by the intradermal injection of $200\;{\mu}g$ of bovine type II collagen with the equal volume of complete Freund's adjuvant at the tail base on day 1. On day 21, the mice were boosted by the intradermal injection of $200\;{\mu}g$ of bovine type II collagen with incomplete Freund's adjuvant. From the first immunization, mice had been administered $Polycan^{TM}$ (21.25, 42.5 and 85 mg/kg), diclofenac and vehicle once a day for 4 weeks, respectively. Collagen-induced hyperimmunities and arthritis signs were markedly and dose-dependently inhibited by treatment of $Polycan^{TM}$ compared with RA control except for tibial cartilages of $Polycan^{TM}$ 21.25 group. $Polycan^{TM}$ effectively inhibited the histopathological changes of collagen-induced arthritis and hyper-immunities.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.283-286
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• 2000

The effects of dissolved oxygen and pH on the cell growth and mass production of high-molecular weight pullulan by A. pullulans ATCC 42023 were evaluated. For the production of commercially useful pullulan with high-molecular weight, the influence of pH control on the pullulan production and growth of A. pullulans was studied in batch fermentation. It was found that the productivity of high-molecular weight pullulan with pH control at 6.5 was higher than that with no pH control. The influence of dissolved oxygen on the pullulan production and growth was studied. It was found that pullulan yield and synthesis rate increased with oxygen availability.