• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.1
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• pp.21-34
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• 1995

For development of microbial additives applicable to in-vessel composting system of food waste, thermophilic bacteria which showed amylase, protease, lipase and cellulase activity were isolated from soil, compost and food waste. Among 81 isolates, the growth characteristic of 20 strains with high enzyme activity were examined. All strains are Gram positive rod with catalase activity and 17 strains are spore formers. At $50^{\circ}C$, most of the strains were able to grow from pH 5 to pH 10 and in presence of 8% of NaCl. In trypticase soy broth, the growth of these strains was greatly increased by aeration, but decreased at elevated temperature above $50^{\circ}C$.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.767-773
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• 2001

We investigated the impacts of the fairy-ring of Tricholoma matsutake on the dynamics of soil microflora and soil enzyme activities by grouping the soils around the fairy-ring of T. matsutake into four regions. The regions were grouped as 'zone of decayed mycorrhizae', 'zone of mycorrhizae for fruiting', 'zone of physiologically active mycorrhizae' and 'zone free from mycorrhizal infection'. Soil fungi and actinomycetes were quite little at the soils around the fairy-ring of T. matsutake compared to those of general forest soils, and there were significant differences among the four regions. The soils with the mycelial cluster of T. matsutake showed about one third of microbial population compared to those in the zone free from mycorrhizal infection, which indicated that T. matsutake took a dominant position within the fairy-ring of the fungus. We could manifest that T. matsutake showed a distinctive characteristics of mycorrhizal fungus since the activities of dehydrogenase were significantly different between the zone of physiologically active mycorrhizae and the zone free from mycorrhizal infection. The dehydrogenase activity was the highest at the early season of fruiting around the fairy-ring of T. matsutake, while the acid-phosphatase activity increased from March to June followed by a slight decrease on August and peaked on October. This phenomenon made us infer that the vitality of T. matsutake be sustained after fruiting.

• KSBB Journal
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• v.25 no.3
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• pp.230-238
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• 2010

A microbial strain having high keratinase activity was isolated from the soil of poultry factories of Gyeonggi or Chungcheong-do. The isolated strain was identified as Bacillus sp. based on its morphological and biochemical characteristics. In this study, the optimal conditions for the production of keratinase by this strain were investigated. The optimal medium composition for the keratinase production was determined to be 3.5% chicken feather as carbon source, 1.0% tryptone as organic nitrogen source, 1.0% $KNO_3$ as inorganic nitrogen source and 0.05% KCl, 0.05% $KH_2PO_4$, 0.03% $K_2HPO_4$ as mineral source and 0.01% yeast extract as growth factor. The optimal temperature and pH was $40^{\circ}C$ and 8.5 with shaking culture (200 rpm), respectively. The maximum keratinase production reached to 123 units/ml after 42 hr of cultivation under the optimal condition. When the hair was used as the sole carbon source, the maximum enzyme activity was 88 units/ml after 120 hr and in this case, the hair added in the medium was not degraded completely but got thinner than the control by 20%.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1126-1135
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• 2012

In order to produce high-quality fermenting composts, bacteria strains with high activities of extracellular enzymes (cellulase, chitinase, amylase, protease and lipase) were isolated from the soils in 6 provinces of Korea, and characterized by 16S rRNA gene sequence analysis and properties. The selected 7 stains inoculated to livestock manure for 2' fermenting time, and experimental treatment divided into 3 groups, B1, B2 and B3, according to microbial activity and enzyme type. Our results showed that microbe applications (B1, B2 and B3) can increase (p<0.05) both rhizomes (17-38%) and enzyme activities (50-81%) in compost after fermenting time, respectively, compared to non-microbe treatment (control). The microbe application also decreased significantly (p<0.05) the $NH_3$ and $H_2S$ gas contents 13.4 and 27.3% compared with control, and the Propionic acid and Butyric acid gas contents 14.5 and 19.6%, respectively, as compared to the control. The microbial degradation rate (%) of pesticides and heavy metals increased significantly (p<0.05) after fermenting time, respectively, as compared to the control. Especially, microbe applications were more effective in total rhizomes yields and bioactivities than non-microbe treatment. Thus the results of this study could help in development of potential bioinoculants and composting techniques that maybe suitable for crop production, and protectable for earth environment under various conditions.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.97-105
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• 1977

1) In order to obtain a microbial strain having a strong yeast cell wall lytic activity, about 156 isolates capable of forming clear zones on baker's yeast-peptone-bouillon agar plate were obtained from soil, mud and water samples and a strain K-42 with the highest lytic activity was identified as Bacillus circulans. 2) Effect of carbon sources on the lytic enzyme production by the K-42 strain was in the decreasing order of maltose>glucan>xylose>control in 2-day culture and of lactose>galactose>glucan>control in 3-day culture. Effect of inorganic nitrogen sources was in the decreasing order of ammonium acetate>sodium nitrate>control in 2-day culture and of ammonium chloride>ammonium oxalate>control in 3-day culture, whereas organic nitrogen sources except milk casein showed an increase in 2-day culture and a decrease in 3-day culture. Synergistic effect of carbon sources and nitrogen sources was not observed. 3) The enzyme production by the K-42 strain was greatly affected by pH change of the culture medium, thus a high lytic activity could be maintained by keeping the pH range of $7{\sim}8$ and adding carbon or nitrogen sources. 4) Optimum conditions for the lytic activity of the K-42 strain were obtained at $pH\;7{\sim}8$ and $60^{\circ}C$ and the extent of hydrolysis toward heated yeast cell wall was 65%.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.245-250
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• 2004

Farmers typically apply the dressed soil (coarse saprolite) for various reasons in the sloped upland with high altitude in Kangwon province. However, little researches on the impacts of application of dressed soil in uplands were conducted. Therefore, it is necessary to assess soil quality in this area and to study adverse effects on soil and water due to application of dressed soil. Coarse saprolite itself showed signiScantly poor chemical properties, Particularly P and organic matter contents were not enough for crops to grow. With respect to biological qualities such as enzyme activity and microbial population, coarse saprolite itself showed poor qualities. For example, bacterial population in coarse saprolite contains six times or ten times smaller populations. Based on survey at Jawoon-ri in Hongchon-gun, this region is susceptible for soil erosion due to massive amounts of coarse saprolite application, undesirably long slope length, etc. When weestimated soil loss, more than 40% of farming field in this region exceeded $11.2MT\;ha^{-1}\;yr^{-1}$. According to experiment by installing sediment basins. the sediment basin with up-down tillage and application with dressed soil had the highest soil loss and runofT, while the sediment basin with contour tillage and without soil dressing showed the lowest soil erosion and runoff.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.563-566
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• 2000

In order to obtain microbial endochitosanase for enzymatic production of chitooligosaccharides from chitosan, we screened four microbes from soil and selected. Bacillus sp. HSB-21 which showed highest activity. Chitosanase, produced from isolating microbe, was endo-type and molecular mass of the enzyme was estimated as 21,000 by active staining. Its optimum pH and temperature were 5.5 and $50^{\circ}C$, respectively. It was stable in the pH range of 3.0 to 8.0 and up to $40^{\circ}C$. It did not produce chitomonosaccharide and produced chitooligosaccharide ranging from chitobiose to chitooctaose as major end-products from chitosan. The chitosanase from Bacillus sp. HSB-21 can be applicable to enzymatic production of chitooligosaccharide which has high degree of polymerization .

• Korean Journal of Ecology and Environment
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• v.35 no.4 s.100
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• pp.306-311
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• 2002

The amount and composition of dissolved organic carbon in wetlands are of great importance for their influence in secondary productivity, various biogeochemical processes, and aquatic ecosystem functions. In the present study, we measured variations of DOC and phenolics concentrations in pore-water of three northern peatlands (bog, fen, and swamp) over a 1-year period. General microbial activity (soil respirometry) and phenol oxidase enzyme activity were determined in the same peatlands to elucidate mechanisms underlying the differences in DOC and phenolics contents. The concentrations of DOC varied 25.5-45.4 (bog),29.2-71.4 (fen), and 13.5-87.6 (swamp) mg/L, while phenolic concentrations ranged 13.3-48.1 (bog), 7.6-29.5(fen) , and 4.9-30.8 (swamp) mg/L. The seasonal variations of DOC and phenolics in the swamp suggest that litterfall may be one of the most important factors for the DOC dynamics in such systems. The lowest microbial activity and phenol oxidase activity were found in the bog, which appears to Induce high percentage of phenolic contents in pore-water from bogs. It is also suggested that not only the DOC concentrations but also composition of DOC is of great importance in wetland biogeochernistry.

• Journal of Urban Science
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• v.13 no.1
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• pp.1-8
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• 2024

정화곤란부지 내 중금속(Pb) 오염토양의 원위치 안정화를 위한 최적 안정화제 선정의 일환으로, 문헌조사를 통해 선정한 3종의 후보 안정화제(mono ammonium phosphate (MAP), iron(III) phosphate (IP) 및 gypsum)에 대해 납에 대한 등온흡착실험을 실시했다. Langmuir 등온흡착식을 적용하여 산출된 각 안정화제의 납 최대흡착량은 MAP, IP 및 gypsum에서 각각 391, 42.4 및 32.2 mg/g으로 나타났다. Freundlich 상수(K_F; 단위 = mg^(1-1/n)·L^1/n/g) 또한 MAP, IP 및 gypsum에서 각각 72.8, 24.5 및 14.3을 나타내, 최대흡착량 및 흡착 친화도 측면에서 MAP가 납의 안정화에 가장 적합함을 확인했다. 3종의 후보 안정화제가 적용된 납 오염토양에 대해 fluorescein diacetate (FDA) 가수분해효소 활성도 평가를 실시하여 안정화제의 적용이 토양의 생태학적 기능에 미치는 영향을 정량화했다. 안정화를 진행하지 않은 대조군 토양의 경우 FDA 가수분해효소의 활성을 지시하는 토양중 fluorescein의 농도가 0.239 mg/g·h을 나타냈으며, MAP, IP 및 gypsum으로 안정화된 토양에서는 각각 0.026, 0.135 및 0.073 mg/g·h를 나타냈다. 안정화제를 첨가한 모든 토양에서 대조군에 비해 FDA 가수분해효소의 활성이 감소했으며, 이는 안정화제 첨가로 인한 토양 염류농도의 증가에 따른 염 스트레스의 영향으로 추정된다. 정화곤란부지 위해도 저감조치로서의 안정화 공법 고려 시, 안정화 처리 이후 대상 중금속이 안정한 형태로 유지되어 낮은 화학적 추출능을 나타내는지 여부도 중요하지만, 잔류 중금속 또는 주입한 안정화제 함유물질 및 중화제 등이 야기할 수 있는 토양 생태계에의 부정적 영향 또한 반드시 고려해야 함을 확인했다.

• Journal of Life Science
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• v.17 no.12
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• pp.1682-1688
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• 2007

To develop multifunctional microbial inoculant, microorganisms with antagonistic activity and biofertilizing activity were screened. Pantoea agglomerans and Bacillus megaterium from our laboratory culture collection, and strain MF12 from soil near poultry farm in Miryang were selected. On the basis of morphological, physiological studies and 16S rDNA sequence analysis, isolate MF12 was identified as the Bacillus pumilis. Three strains were studied for insoluble phosphate solubilization, indole-3-acetic acid (IAA) and siderophore production, ammonification ability, hydrolytic enzyme production and antifungal activity against phytopathogenic fungi. P. agglomerans did not produce any visible clear zone on agar plate containing 0.5% $Ca_3(PO_4){_2}$ as a sole phosphorus source. However, this strain could solubilize insoluble phosphate in liquid medium. All strains produced IAA ranged from $3{\sim}639{\mu}g/ml$ depending on culture time and had ammonification ability. Among three strains, only P. agglomerans produced siderophore. P. agglomerans produced pectinase and lipase, B. megaterium produced amylase, protease and lipase while B. pumilis produced protease and lipase. P. agglomerans showed antifungal activities against phytopathogenic fungi, Fusarium oxysporum and Colletotrichum gloeosporioides. B. pumilis showed antifungal activities against Botrytis cinerea, Sclerotinia sclerotiorum and Phythium ultimum.