• The Korean Journal of Mycology
• /
• v.49 no.3
• /
• pp.393-397
• /
• 2021

The unrecorded fungus Galactomyces pseudocandidus de Hoog & M.T. Sm. was isolated and cultured from an introduced species, Procambarus clarkii, in Korea. Two related species, Galactomyces citri-aurantii and Geotrichum candidum, have been reported, but no other Galactomyces spp. have been found in Korea. In this study, we isolated G. pseudocandidus from the digestive tract of American crayfish using RGY (river water-glucose-yeast) medium and then compared the morphological and molecular characteristics of this species with those of related species. As a result, we confirmed that G. pseudocandidus is an unrecorded fungus in Korea, so we described and reported the cultural characteristics and microstructures, such as conidia.

• Mycobiology
• /
• v.49 no.1
• /
• pp.69-77
• /
• 2021

The application of antagonistic fungi for plant protection has attracted considerable interest because they may potentially replace the use of chemical pesticides. Antipathogenic activities confirmed in volatile organic compounds (VOCs) from microorganisms have potential to serve as biocontrol agents against pre- and post-harvest diseases. In the present study, we investigated Galactomyces fungi isolated from rotten leaves and the rhizosphere of cherry tomato (Lycopersicon esculentum var. cerasiforme). VOCs produced by Galactomyces fungi negatively affected the growth of phytopathogenic fungi and the survival of nematodes. Mycelial growths of all nine examined phytopathogenic fungi were inhibited on agar plate, although the inhibition was more intense in Athelia rolfsii JYC2163 and Cladosporium cladosporioides JYC2144 and relatively moderate in Fusarium sp. JYC2145. VOCs also efficiently suppressed the spore germination and mycelial growth of A. rolfsii JYC2163 on tomatoes. The soil nematode Caenorhabditis elegans exhibited higher mortality in 24 h in the presence of VOCs. These results suggest the broad-spectrum activity of Galactomyces fungi against various plant pathogens and the potential to use VOCs from Galactomyces as biocontrol agents.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.5
• /
• pp.800-808
• /
• 2003

Three strains of yeasts, Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59, produced volatile flavor compounds during fermentation. To investigate these volatile flavor compounds, the liquid culture broth of the three yeast strains were extracted with methylene chloride, and then GC and GC-MS analyses were conducted. Flavor analyses revealed that 5, 12, and 15 kinds of volatile compounds were isolated, and 4, 8, and 11 volatile flavor compounds were identified, respectively. Phenylethyl alcohol was identified with the common volatile flavor compound of Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59. 1H-indole-3-ethanol, a precursor of plant growth hormone, was identified from Pichia anomala SKM-T.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.1
• /
• pp.22-28
• /
• 2004

Livestock industry requires alternatives of antibiotics to prevent environmental pollution and to maintain public health. We herein report on an effective method to reduce ammonia from livestock manure, and confirmed environmentally-friendly livestock production by adding three types of yeast probiotics, Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59, into the feed stuff, separately and/or mixed, and these three types of yeasts were administered to the Hy-line brown layers for 8 weeks. Compared with control, the laying performance, the egg quality, and the number of intestinal lactic acid producing bacteria of the treated group were improved and/or increased significantly. Pichia anomala SKM-T potently reduced ammonia production from poultry manure, and the other strains were also able to reduce the ammonia from it. The optimum condition for the reduction of ammonia with Pichia farinosa SKM-1, Pichia anomala SKM-T, and Galactomyces geotrichum SJM-59 was obtained by using the augmented centroid-simplex design. The ratio of optimum condition was Pichia farinosa SKM-1:Pichia anomala SKM-T:Galactomyces geotrichum SJM-59=0.295:0.209:0.080, and the estimate was -123.36 (p=0.0l38). An ability to reduce the ammonia production from livestock manure was maintained at $30^{\circ}C$ for 15 weeks.

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.493-497
• /
• 2005

Probiotics are generally excreted within a few days if their ingestion in feces at the same rate as or even more quickly than a transit marker (meaning not clear). Ability of probiotics to adhere to intestine prolongs their persistence in gastrointestinal tract, allowing them to exert healthful effects longer. Hydrophobicities, zeta potentials, Alcian blue-binding capacities, and sedimentation profiles of Pichia farinosa SKM-1, P. anomala SKM-T, and Galactomyces geotrichum SJM-59 were determined to evaluate characteristic properties of cell surfaces responsible for adhesion. Results of intestinal Caco-2 cell line in vitro and murine intestine in vivo studies revealed these strains exhibit adhesive properties regardless of their cell surface hydrophobicity.

• Food Science and Biotechnology
• /
• v.14 no.4
• /
• pp.487-492
• /
• 2005

Simple competition plate bioassays of Pichia anomala SKM-T and Galactomyces geotrichum SJM-59 were conducted to evaluate their potential as biological control agents that inhibit growth of Botrytis cinerea during post-harvest storage of strawberries (Fragaria ${\times}$ ananassa Duche, Red-Pearl). Occurrence rates of fungi on the surface of yeast-treated strawberries were evaluated during storage at $4^{\circ}C$. P. anomala SKM-T and G. geotrichum SJM-59 showed antifungal activities on agar plate, and P. anomala SKM-T maintained its desirable antifungal activity on surface of strawberries and its physicochemical properties during storage. Sensory evaluation was based on kinesthetics and consumer acceptability. Due to its potential antifungal activity, P. anomala SKM-T could function as biological control agent against spoilage fungi during post-harvest storage of strawberries.

• Food Science and Preservation
• /
• v.14 no.1
• /
• pp.94-99
• /
• 2007

To investigate the effects of Pichia anomala SKM-T and Galactomyces geotrichum SJM-59 on Baechu kimchi fermentation, lyophilized yeasts were added to Baechu kimchi and co-cultured at room temperature ($20{\pm}2^{\circ}C$) for 7 days. Desirable pH and acidity levels appeared by 3 days of fermentation in both the control culture and that with added G. geotrichum SJM-59. Furthermore, the culture with G. geotrichum SJM-59 sustained a desirable pH and acidity level until 5 days of co-culture. The pH of the culture with P. anomala SKM-T decreased slowly and was significantly higher than that of control throughout the experimental period. As fermentation time increased, the acidity of the culture with P. anomala SKM-T increased gradually. However, this culture maintained a desirable acidity level throughout the experiment. The number of lactic acid bacteria in the culture with P. anomala SKM-T was higher than in the culture with G. geotrichum SJM-59, or the control culture, throughout the experiment. The highest LA/TM ratio appeared after 3 nays of fermentation in the control culture, and on the 5 day of the yeasts added co-cultures. On sensory evaluation, no differences were detected between control and the culture with G. geotrichum SJM-59 arter 3 days of fermentation. The co-cultures with yeasts received high marks in umami taste. The co-culture with P. anomala SKM-T showed better texture properties than did the control culture. It was considered that fermentation times were delayed by addition of G. geotrichum SJM-59 or P. anomala SKM-T to Baechu kimchi fermentation.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.4
• /
• pp.409-415
• /
• 2009

Galactomyces geotrichum MTCC 1360 degraded the Scarlet RR(100 mg/l) dye within 18 h, under shaking conditions(150 rpm) in malt yeast medium. The optimum pH and the temperature for decolorization were pH 12 and $50^{\circ}C$, respectively. Enzymatic studies revealed an induction of the enzymes, including flavin reductase during the initial stage and lignin peroxidase after complete decolorization of the dye. Decolorization of the dye was induced by the addition of $CaCO_3$ to the medium. EDTA had an inhibitory effect on the dye decolorization along with the laccase activity. The metabolites formed after complete decolorization were analyzed by UV-VIS, HPLC, and FTIR. The GC/MS identification of 3 H quinazolin-4-one, 2-ethylamino-acetamide, 1-chloro-4-nitro-benzene, N-(4-chloro-phenyl)-hydroxylamine, and 4-chloro-pheny-lamine as the final metabolites corroborated with the degradation of Scarlet RR. The phytotoxicity study revealed the nontoxic nature of the final metabolites. A possible degradation pathway is suggested to understand the mechanism used by G. geotrichum and thereby aiding development of technologies for the application of this organism to the cleaning-up of aquatic and terrestrial environments.

• Food Science and Biotechnology
• /
• v.16 no.2
• /
• pp.193-197
• /
• 2007

In order to investigate the effects of Pichia farinosa SKM -1, Pichia anomala SKM-T, Galactomyces geotrichum SJM-59, and Saccharomyces cerevisiae on extending the shelf life of kkakdugi, 4 kinds of lyophilized yeasts adding kkakdugis were prepared and stored at $4^{\circ}C$ for 30 days. Except S. cerevisiae adding group, 3 kinds of yeast adding groups were maintained their desirable levels (ca. pH 4.2 and 0.6% acidity) during the fermentation. The hardness of yeast adding groups was higher than those of control during the experiments. The number of yeast and the ratio of lactic acid against to total bacteria in P. farinosa SKM-1, P. anomala SKM-T, and G geotrichum SJM-59 adding groups were lower than that of control and/or S. cerevisiae adding group. Based on acidity, kkakdugi made with P. farinosa SKM-1, P. anomala SKM-T, and G geotrichum SJM-59 remained edible about 10 days longer than the control product.

• Journal of Microbiology and Biotechnology
• /
• v.28 no.8
• /
• pp.1360-1366
• /
• 2018

The fungi associated with termites secrete enzymes such as laccase (multi-copper oxidase) that can degrade extracellular wood matrix. Laccase uses molecular oxygen as an electron acceptor to catalyze the degradation of organic compounds. Owing to its ability to transfer electrons from the cathodic electrode to molecular oxygen, laccase has the potential to be a biocatalyst on the surface of the cathodic electrode of a microbial fuel cell (MFC). In this study, a two-chamber MFC using the laccase-producing fungus Galactomyces reessii was investigated. The fungus cultured on coconut coir was placed in the cathode chamber, while an anaerobic microbial community was maintained in the anode chamber fed by industrial rubber wastewater and supplemented by sulfate and a pH buffer. The laccase-based biocathode MFC (lbMFC) produced the maximum open circuit voltage of 250 mV, output voltage of 145 mV (with a $1,000{\Omega}$ resistor), power density of $59mW/m^2$, and current density of $278mA/m^2$, and a 70% increase in half-cell potential. This study demonstrated the capability of laccase-producing yeast Galactomyces reessii as a biocatalyst on the cathode of the two-chamber lbMFC.