• Korean Journal of Microbiology
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• v.33 no.2
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• pp.131-135
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• 1997

Several microorganisms capable of producing protopectinase, which catalyzes dissociation of plant tissue to single cells, were isolated from soils. Crude enzymes prepared from culture supernatants of the strains released potato cells as a single cell from potato tissues. One of the isolated strains showing higher activity of protopectinase was selected and identified as Rhizopus sp. from the morphological characteristics. For preparing single cells from potato tissues, optimum enzyme activity of protopectinase, which was prepared from culture filtrate of Rhizopus sp. R2, was obescrved at $40^{\circ}C$ and pH 4.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.126-130
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• 1988

Promoters of an alkali-tolerant Bacillus sp. isolated from soil have been cloned in Bacillus subtilis using promoter probe vector pPL703. The CAT specific activity of a clone harboring the strongest promoter activity among these transformants was 8.01. This activity was 2.5 times higher than that of Bacillus subtilis harboring expression vector pPL708 and was increased after the end of the logarithmic growth phase. In the 2.8kb of inserted DNA fragment, BamHI and Sal I recognition sites were located.

• Microbiology and Biotechnology Letters
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• v.28 no.3
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• pp.156-160
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• 2000

In an attempt to develop an unique enzyme (inulinase) for fructan utilization. bacterial strains were isolated [yom soil. Stram 96-11 secreting inulinase o[ high activity was tentatively identificated as Arthrobacter protophmmiae/ranwsus. The optimum culture conditions o[the slnin for the production of the inulinase were as follow: inorganic saIl basal medium contained sources fl % (w/v) inulin, 1 % (w/v) tryptone, and 1 % (w/v) $NH_4Cl$]. $35^{\circ}C$, initial pH 7.5. aeration 1 vvm and agitation 200 rpm.

• Korean Journal of Organic Agriculture
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• v.30 no.3
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• pp.393-407
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• 2022

The effect of Neobacillus sp. JC05 extract on the defense response in cucumber plants against root-knot nematode (RKN) was evaluated. As a result of drench treatment of JC05-extract in cucumber plants, formation of egg mass per plants and disease severity were significantly decreased compared to untreated control plants; the malondialdehyde contents also decreased in JC05-extract treated plants. When eggs of Meloidogyne incognita were inoculated, cucumber plants treated with JC05-extract elevated pathogenesis-related gene expression such as chitinase and lipoxygenase, these are well known as inducing resistance in plants, in addition, peroxidase among antioxidant enzymes was significantly activated. Moreover, the JC05-extract enhanced FDAse activity in soils grown cucumber plants inoculated by eggs of M. incognita. Taken together, these results suggest that the JC05-extract could involve in activation of defense-related mechanisms of cucumber plants and result in decrease of disease occurrence caused by M. incognita.

• Microbiology and Biotechnology Letters
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• v.18 no.1
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• pp.44-48
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• 1990

Alkalophilic sp. YC-335 isolated from soil was capable of producing large amount of cyclodextrin glycosyltransferase (CGTase) in culture broth. This enzyme was successively purified 52.9 folds with 17.8 yield by ethanol precipitation, DEAE-Toyopearl column chromatography and Sephadex G-100 column chromatography. The purified enzyme have a molecular weight of approximately 75,000 estimated by SDS polyaerylamide gel electrophoresis. The optimum pH and temperature for the enzyme activity were 6.0 and 5$0^{\circ}C$, respectively. The enzyme stable between pH 6 and 10, and up to 5$0^{\circ}C$. The thermostability of the enzyme was increased up to 6$0^{\circ}C$ by the addition of 15mM CaCl$_2$.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.4
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• pp.64-71
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• 2009

Excessive soil organic matter (SOM) is detrimental to turfgrass quality when used intensively in sand-based root zones, thereby affecting the sustainability of turfgrass systems. As part of a major project examining the sustainable management of SOM on golf greens, microbial decomposition on soil organic matter accumulation with depth was assessed and the effect of soil air-condition improvement and Ca fertilization was investigated by soil microbial respiration (SMR). Three soil samples from three depths(0~5, 5~10, and 10~15cm) of 5 year and 30 year old green were analyzed for SOM content. In 30 year old green, SMR and dehydrogenase activity(DHA) were analyzed to assess the soil microbial decomposition with depth. It was then divided into 4 plots: untreated as a control, dolomite-treated, 0~5cm deep section-removed, and 0~5 cm deep section-removed+dolomite-treated. After treatment, three soil samples were taken at 1, 2 and 4 weeks by the above-mentioned method, and analyzed for SMR to better understand SOM decomposition. SOM accumulation in the 0~5cm depth of golf greens can be controlled by intensive cultivation such as coring, but below 5cm is more difficult as the results showed that SOM content below 5cm increased over time. Soil microbial decomposition of organic matter will be necessary to reduce SOM accumulation, but SMR below 5cm was low and wasn't significantly altered by increasing exposure to air and fertilizing with Ca. As a result, aeration treatments such as coring and Ca fertilization might not be effective at improving soil microbial decomposition below 5cm depth in aged greens.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.479-499
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• 2019

This study was conducted to investigate the responses of soil properties and microbial communities to different agricultural management and soil types, including organic management in Andisols (Org-A), organic management in Non-andisols (Org-NA), conventional management in Andisols (Con-A) and conventional management in Non-andisols (Con-NA) by using a pyrosequencing approach of 16S rRNA gene amplicon in Radish farms of volcanic ash soil in Jeju island. The results showed that agricultural management systems had a little influence on the soil chemical properties but had significant influence on microbial communities. In addition, soil types had significant influences on both the soil chemical properties and microbial communities. Organic farming increased the microbial density of bacteria and biomass C compared to conventional farming, regardless of soil types. Additionally, Org-NA had the highest dehydrogenase activity among treatments, whereas no difference was found between Org-A, Con-A and Con-NA and had the highest species richness (Chao 1) and diversity (Phyrogenetic diversity). Particularly, Chao 1 and Phyrogenetic diversity were increased in organic plots by 12% and 20%, compared with conventional plots, respectively. Also, regardless of agricultural management and soil types, Proteobacteria was the most abundant bacterial phylum, accounting for 21.9-25.9% of the bacterial 16S rRNAs. The relative abundance of putative copiotroph such as Firmicutes was highest in Org-NA plot by 21.0%, as follows Con-NA (13.1%), Con-A (6.7%) and Org-A (5.1%.), respectively and those of putative oligotrophs such as Acidobacteria and Planctomycetes were higher in Con-A than those in the other plots. Furthermore, LEfSe indicated that organic system enhanced the abundance of Fumicutes, while conventional system increased the abundance of Acidobacteria, especially in Non-andisols. Correlation analysis showed that total organic carbon (TOC) and nutrient levels (e.g. available P and exchangeable K) were significantly correlated to the structure of the microbial community and microbial activity. Overall, our results showed that the continuous organic farming systems without chemical materials, as well as the soil types made by long-term environmental factors might influence on soil properties and increase microbial abundances and diversity.

• Journal of Animal Science and Technology
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• v.51 no.5
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• pp.427-432
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• 2009

This study was undertaken to screen a high xylanase and mannanase producing microbes. In the first experiment, screening was undertaken against 50 samples of microorganisms having xylanase and mannanase activities from soil and fallen leaves. The screening process has focused on picking out fungi having high xylanase and mannanase activities under the solid-state fermentation. The xylanase and mannanase activities of 6 screened microbes were 0.9~1.6 unit/mL and 0.2~0.4 unit/mL, respectively, under the submerged fermentation condition. However, under the solid-state fermentation, xylanase and mannanase activities were 103.7~220.0 unit/g and 20.1~40.3 unit/g, respectively. Finally one microbe (E-3) was selected and its xylanase and mannanase activities were 197.3 unit/g and 39.9 unit/g, respectively. The morphological and molecular biological classification of E-3 showed 99% homology with the Aspergillus niger.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.502-506
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• 1995

A Bacillus strain which produces ${\beta}-galactosidase$ with high transgalactosylation activity, was isolated from soil and tentatively designated as Bacillus sp. A1. When ${\beta}-galactosidase$ from Bacillus sp. A1 reacted with 40% (w/w) lactose, transgalactosylation ratio reached up to 90% at the 70% conversion of the initial lactose. The biosynthesis of the enzyme in Bacillus sp. A1 required lactose as an inducer and was repressed by glucose. Observing that the addition of amino acids to culture medium resulted in enhancing, to a significant extent, both the growth and the enzyme production of the strain, yeast extract and commercially available hydrolysates of protein were examined for the suitability as amino acid source. As it turned out, SMP, an enzymatic hydrolysis product of soybean protein from Fuji Oil Co.(Japan), was the most suitable for optimization of the culture medium. When Bacillus sp. A1 was cultured in the presence of 0.5% SMP and 2% lactose, the enzyme activity increased up to $1.8\;U/m{\ell}-broth$.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.987-994
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• 2010

To investigate the effect of long term application of organic matter in upland soils, plots for treatments of NPK, NPK+pig manure compost, rape seed cake, rice straw compost, and green manure were set up. Populations of Bacillus and Gram negative bacteria were high in the plot treated with green manure application, but microbial biomass was increased with chemical fertilizer or pig manure compost in upland soils. Activities of phosphomonoesterase and dehydrogenase were high with organic matter application comparing to control. Cluster patterns analysed using phospholipid fatty acid of plots treated with rice straw and or pig manure compost were clearly different comparing with other treatments. Dominant bacteria in upland soils were Bacillus flexus, B. subtilis and B. megaterium. And the strains isolated from upland soils had amylase, protease and lipase activities.