• Mycobiology
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• 제48권3호
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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.

• 한국균학회지
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• 제48권2호
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• pp.161-167
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• 2020

국내에 자생하는 지렁이로(붉은줄지렁이)의 장에서 야생효모를 분리, 동정하고자 하였다. 지렁이는 고양시 난지 물 재생 센터에서 분양 받았으며, 지렁이 5마리에서 19개의 야생효모를 분리하였다. 효모의 D1/D2 영역으로 동정하여 국내에 보고되지 않은 효모 3균주를 선별하였다. 국내 미기록종 효모인 Yarrowia deformans YP242 (=KACC48778), Sporidiobolus pararoseus YP66(=KCTC27963), Naganishia liquefaciens YI9 (=KACC48948) 균주는 위상차현미경, API 20C AUX kit를 통해 균학적 특성을 조사하였다. YP242, YI9, YP66 균주의 세포 모양은 타원형이며, 집락은 볼록하고, 부드러운 재질을 가지는 것으로 관찰되었다. 탄소원 활성 측정 결과, YP242는 glycerol, L-arabinose, N-acetyl-D-glucosamine을, YP66는 N-acetyl-D-glucosamine을, liquefaciens YI9는 2-keto-D-gluconate을 탄소원으로 사용할 수 있음을 확인하였다.