• Mycobiology
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• v.48 no.3
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• pp.195-203
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• 2020

Marine yeasts have tremendous potential in industrial applications but have received less attention than terrestrial yeasts and marine filamentous fungi. In this study, we have screened marine yeasts for amylolytic activity and identified an amylase-producing strain PH-Gra1 isolated from sea algae. PH-Gra1 formed as a coral-red colony on yeast-peptone-dextrose (YPD) agar; the maximum radial growth was observed at 22 ℃, pH 6.5 without addition of NaCl to the media. Based on the morphology and phylogenetic analyses derived from sequences of internal transcribed spacer (ITS) and a D1/D2 domain of large subunit of ribosomal DNA, PH-Gra1 was designated Sporidiobolus pararoseus. S. pararoseus is frequently isolated from marine environments and known to produce lipids, carotenoids, and several enzymes. However, its amylolytic activity, particularly the optimum conditions for enzyme activity and stability, has not been previously characterized in detail. The extracellular crude enzyme of PH-Gra1 displayed its maximum amylolytic activity at 55 ℃, pH 6.5, and 0%-3.0% (w/v) NaCl under the tested conditions, and the activity increased with time over the 180-min incubation period. In addition, the crude enzyme hydrolyzed potato starch more actively than corn and wheat starch, and was stable at temperatures ranging from 15 ℃ to 45 ℃ for 2 h. This report provides a basis for additional studies of marine yeasts that will facilitate industrial applications.

• The Korean Journal of Mycology
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• v.48 no.2
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• pp.161-167
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• 2020

The goal of this study was to isolate and characterize the wild yeast strains from the gut of earthworm(Eisenia andrei). The 19 yeast strains isolated from 5 gut of earthworm samples from Nanji water regeneration center in Goyang-si, Gyeonggi-do, Korea. Among them, 16 strains were recorded and 3 strains, Yarrowia deformans YP242 (=KACC48778), Sporidiobolus pararoseus YP66 (=KCTC27963) and Naganishia liquefaciens YI9 (=KACC48948) were recorded for the first time in Korea. The microbiological characteristics of these previously unrecorded yeasts were investigated. All three strains were oval-shaped, convex and smooth. However, they showed some differences in colony color and result of carbon assimilation assays. YP242 was white-colored and assimilated glycerol, L-arabinose and N-acetyl-D-glucosamine as carbon sources. YP66 was red-colored and assimilated D-Saccharose. YI9 was whitecolored and positive for 2-keto-D-gluconate assimilation.