• The Korean Journal of Mycology
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• v.51 no.4
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• pp.265-276
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• 2023

This study aimed to isolate and characterize fungi from freshwater environments in South Korea and evaluate their extracellular enzyme activities. Fungal strains were collected from various freshwater sources and identified using phylogenetic analysis. The isolated fungi included known aquatic hyphomycetes and previously unreported species. Extracellular enzyme, including those of protease, amylase, lipase, cellulase, laccase, and chitinase, activities were evaluated. Among the isolated strains, several showed high enzyme activity, suggesting their potential role in organic matter decomposition in freshwater ecosystems. This research expands our knowledge of the diversity and enzyme activities of the fungi in freshwater environments, contributing to our understanding of their ecological roles.

• The Korean Journal of Ecology
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• v.18 no.3
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• pp.409-418
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• 1995

As a part of studying the function and structure of the mudflat environment of the Yellow Sea, seawater samples in the overlying waters of sediment near Daesan were collected every hour on March 29 (spring tides) and on April 5 (neap tides), 1995 to study the diurnal distribution of aerobic saprophytic bacteria and their extracellular enzyme activities. The diurnal distribution of aerobic saprophytic bacteria ranged from 1.0 X $10^{2}$ to 7.07 X $10^{3}$ cfu /ml at spring tides and from 1.0 X $10^{2}$ to 8.3 X $10^{3}$ cfu /ml at neap tides. The diurnal variations of aerobic saprophytes at the suface waters were greater than those of middle and bottom waters. However, th diurnal fluctuation of saprophyte numbers at spring tides showed no significant difference compared with that at neap tides. The numbers of three physiological groups of aerobic hacteria (proteolytic, lipolytic and amylolytic bacteria) at the surface waters during spring and neap tides were lower than those at the middles and bottom waters. The diurnal variations of five extracellular enzyme activities at the surface waters during the survey period showed lower values than those at the middle and botton waters. Among the measured extracellular enzyme activities, phosphatase showed the highest. However, the activities of amylase, chitinase and cellulase showed a similar tendency.

• Korean Journal of Microbiology
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• v.40 no.3
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• pp.230-231
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• 2004

The mycelia of Sparassis crispa DSMZ 5201 were cultivated at $24^{\circ}C$ for 15 days in yeast-malt extract-glucose broth (pH 4.0) and the filtrate was used as crude enzyme solution to determined the extracellular enzyme activity. The specific activity of $\alpha$-amylase was 44.27 unit/protein. The specific activities of protease, CMCase, $\beta$-glucosidase, chitinase, exo-$\beta$-l,4-glucanase were relatively high. However, a very little activity of xylanase was found.

• Mycobiology
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• v.36 no.1
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• pp.74-76
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• 2008

To obtain basic information on the biochemical property of basidiospores of shiitake mushroom (Lentinula edodes), the ability of producing extracellular enzyme was assessed using a chromogenic plate-based assay. For the aim, amylase, avicelase, $\beta$-glucosidase, CM-cellulase, pectinase, proteinase, and xylanase were tested against monokaryotic strains generated from forty basidiospores of two different parental dikaryotic strains of shiitake mushroom, Sanjo-101Ho and Sanjo-108Ho. These two parental strains showed different degree of extracellular enzyme activity. No identical patterns of the degree of enzyme activity were observed between monokaryotic strains and parental strains of the two shiitake cultivars. The degree of extracellular enzyme activity also varied among monokaryotic strains of the two shiitake cultivars. Our results showed that dikaryotic parental strains of shiitake mushroom produce monokaryotic basidiospores having very diverse biochemical properties.

• Mycobiology
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• v.39 no.2
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• pp.125-128
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• 2011

Enzyme activities of Cenococcum geophilum isolates were examined on enzyme- specific solid media. Deoxyribonuclease, phosphatase, and urease were detected in all isolates, whereas cellulase was not detected in any of the isolates. Variations in enzyme activities of amylase, caseinolysis, gelatinase, lipase, and ribonuclease were observed among isolates.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.79-90
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• 1994

Water samples were taken at 6 stations from the mouth of Keum River to Kogunsan Archipelago of West Sea during December, 1991 to August, 1992, to determine the distribution of heterotrophic bacteria, their biovolumes and heterotrophic activities. Heterotrophic marine bacteria ranged from $1.0\;{\times}\;10^3to\;5\;{\times}\;10^5c.f.u.$ /ml. As for morphological distribution measured by epifluorescence microscopy, rod-shaped bacteria were between 45% and 72% of all cells during investigation period. Average biovolume of sampled bacteria ranged from $(7.69\;{\pm}\;0.18)\;{\times}10^{-2}to\;(8.18\;{\pm}\;0.38)\;{\times}\;10^{-2}\;{\mu}m^3$ for coccoid bacteria, and from $(6.09\;{\pm}\;0.29)\;{\times}10^{-2}to\;(7.72\;{\pm}\;0.41)\;{\times}\;10^{-2}\;{\mu}m^3$ for rod-shaped ones. The activities of extracellular enzymes ranged from 0.01 to 2.6 ${\mu}M$ /l /hr for glucosidase, from 0.01 to 2.6 ${\mu}M$ /l /hr for amylase, from 0.01 to 8.86 ${\mu}M$ /I /hr phosphatase and from 0.01 to 0.94 ${\mu}M$ /l /hr for chitinase. Extracellular enzyme activities were higher in summer season than in other sampling periods, and phosphatase showed the highest activity among measured extracellular enzymes. Bacterial distribution and their extracellular enzyme activities were associated with water temperature and organic nutrients, but bacterial cell volumes showed no direct relationship with extracellular enzyme activities.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.496-501
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• 1998

The mycelia of Tricholoma matsutake DGUM 26001, 26101, 26210 and FRI 91024 were used to determine the extracellular enzyme activity in mycelia. When the filtrate of culture broth after 30-day cultivation at $24^{\circ}C$ was used as a crude solution of extracellular enzyme, the average specific activity of ${\alpha}-amylase$ was 6142.3 unit/mg protein. The specific activity of xylanase was comparatively high. However, little or no enzyme activities were found for ${\beta}-glucosidase$, ligninase, CMCase, chitinase, protease, and lipase.

• Applied Biological Chemistry
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• v.30 no.2
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• pp.169-178
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• 1987

The extracellular and intracellular inulases from Kluyveromyces marxianus were purified and characterized. The maximum production of both inulases was achieved at stationary phase in a pH-controlled medium at pH 5 with yeast nitrogen base as organic nitrogen source. Each enzyme was concentrated by tannic acid precipitation and separated into two fractions by DEAF-cellulose chromatography. Electrophoretic analysis showed that the four fractions had three glycoprotein bards each. Only main glycoprotein band, however, had both inulase and invertase activities. There were no significant differences between two enzymes in the optimum pH and temperature. But the intracellular inulases had higher heat stability and less affinity toward inulin than the extracellular enzymes do. All the purified enzymes were considered to be exo-inulases using hydrolyzate analysis with TLC.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.59-61
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• 2000

The various extracellular enzymes produced by lactic acid bacteria isolated from kimchi were assayed to improve the shelf-life of kimchi. Peroxidase was not detected in all tested lactic acid bacteria and small amount of ascorbic acid oxidase was detected in Pediococcus pentosaceus and Lactobacillus brevis. In case of $\alpha$-amylase, 27.8 and 20.9 unit/mg were shown in Pediococcus acidilactici and Pediococcus pentosaceus, respectively but $\beta$-amylase and protease activities were very low. The enzyme related to textural property of kimchi, pectinesterase showed low activity but polygalacturonase activity was 0.28 unit/mg in Lactobacillus homohiochii and 0.27 unit/mg in Lactobacillus plantarum.

• The Microorganisms and Industry
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• v.12 no.2
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• pp.36-39
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• 1986