• Journal of Life Science
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• v.27 no.7
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• pp.805-811
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• 2017

In the previous paper, we isolated a bacterium that can hydrolyze various organic materials from soybean paste, including cellulose, lipids, starch, and protein. The activity and chemical properties of the crude enzymes produced by the isolate Bacillus subtilis CK-2 were further investigated. Cellulase showed the highest activity at pH 5.0 and $55^{\circ}C$. The stability of cellulase was maintained within the ranges of pH 5.0~10.0 and $20{\sim}50^{\circ}C$. Cellulolytic enzymes were activated by a $Co^{2+}$ ion, demonstrating the highest activity at a 0.45%(w/v) concentration of $Co^{2+}$. The optimal conditions for amylase were pH 5.0 and $50^{\circ}C$. The activity of amylase was stable within the ranges of pH 4.0~5.0 and $20{\sim}50^{\circ}C$. The $Co^{2+}$ ion was also necessary for amylase activity, which was the highest at a 0.2%(w/v) concentration of $Co^{2+}$. The optimal pH and temperature conditions of protease were pH 8.0 and $50^{\circ}C$. The activity of protease was stable within the ranges of pH 7.0~8.5 and $20{\sim}50^{\circ}C$. Protease activity was catalyzed by $Mn^{2+}$, which was the highest at a 0.125%(w/v) concentration of $Mn^{2+}$. The isolate B. subtilis CK-2 demonstrated a high activity of autolysin. Based on these results, we identified and suggested the optimal pH, temperature, and metal ion concentration in the use of the hydrolytic enzymes of B. subtilis CK-2 for industrial purposes.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.249-258
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• 2015

In this paper, the autolysis process of Saccharomyces cerevisiae FX-2 (S. cerevisiae FX-2) via, a variety of endogenous enzyme, was investigated systematically by analyzing changes in physicochemical parameters in autolysate, surface morphology and the internal structure of the yeast cells. As an explicit conclusion, the arisen autolysis depended on the pH and the optimal pH was found to be 5.5. Based on the experimental data and the characteristics of mycelia morphology, a hypothesis is put forward that simple proteins in yeast vacuolar are firstly degraded for utilization, and then more membrane-bound proteins are hydrolyzed to release hydrolytic enzymes, which arouse an enzymatic reaction to induce the collapse of the cell wall into the cytoplasm.

• Journal of the Korean Applied Science and Technology
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• v.26 no.1
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• pp.10-17
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• 2009

This study investigated the effect of kilning condfition on the diastatic power and activities of protease, $\alpha$-amylase, and $\beta$-amylase in rice malt. Common rice (Oryza sativa) was steeped at $30^{\circ}C$ for 50 h, germinated at $30^{\circ}C$ for 7 days, and kilned at $50^{\circ}C$ for 24 h. The moisture content and enzymatic activities were determined under various kilning times. As a result, the moisture content was reduced from 42.1 % to 3.9% after 24 h of kilning at $50^{\circ}C$. The protease activity of rice malt showed lower value than that of barley malt. All enzymatic activities were decreased during the kilning stage. Results indicated that after prolonged kilning at $50^{\circ}C$, the inactivation of hydrolytic enzymes might be occurred. Even though the amylolytic activity of malted rice showed low value, the rice malt shows the potential characteristics as ingredient for the brewing and cereal industries.

• Journal of Chest Surgery
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• v.17 no.4
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• pp.574-586
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• 1984

Although corticosteroid have been shown to stabilize lysosomal membranes and prevent release of hydrolytic enzymes, the mechanism of membrane stabilization remains obscure. This study described functional assessment of efficiency of methylprednisolone in GIK solution by using a isolated Rat Heart Model. Isolated rat heart were subjected to a 2-minute period of coronary infusion with a cold GIK or methylprednisolone mixed cold GIK solution immediately before and also at the midpoint of a 60-minute period of hypothermic [$10{\pm}1^{\circ}C$] ischemic arrest. The result of this were as follow: 1.Spontaneous heart beat after ischemic arrest occurred 11 second later after Langendorffs reperfusion in the methylprednisolone mixed GIK group and 14 second later in the control group. 2.The percentage of recoveries of heart rate at 30 minute after postischemic working heart perfusion was 88.6\ulcorner.6% in the methylprednisolone mixed GIK group. This percentage of recovery was not significantly greater than the control group. 3.The percentage of heart function at 30 minute after postischemic working heart perfusion were; peak aortic pressure $90.8{\pm}4.5%$ coronary flow $87.5{\pm}1.45$ and aortic flow $74.9{\pm}11.8%$ in the methylprednisolone mixed GIK group. This percentage of recovery was significantly greater than the control group. [p<0.05]

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.5-14
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• 2006

Streptomycetes are Gram-positive microorganisms producing secondary metabolites through unique physiological differentiation [4]. The microbes show unusual morphological differentiation to form substrate mycelia, aerial mycelia, and arthrospores on solid medium [19]. Substrate mycelium growth is sustaining with sufficient nutrients in the culture medium. The concentration of a specific individual substrate in the culture environment is the most important extracellular factor allowing vegetative mycelia growth, where extracellular hydrolytic enzymes participate in the utilization of waterinsoluble substrates. However, with starvation of nutrients in the culture medium, the vegetative mycelia differentiate to aerial mycelia and spores. It has been considered that shiftdown of essential nutrients for mycelia growth is the most important factor triggering morphological and physiological differentiation in Streptomyces spp. Since proteineous macromolecule compounds are the major cellular components, these are faced to endogenously metabolize following a severe depletion of nitrogen source in culture nutrients (Fig. 1). Various proteases were identified of which production was specifically related with the phase of mycelium growth and also morphological differentiation. The involvement of proteases and protease inhibitor is reviewed as a factor explaining the mycelium differentiation in Streptomyces spp.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.168-172
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• 2006

Soy sauce was fermented at $20^{\circ}C$ for 100 days in onggi containers (ethnic Korean earthenware) which had been fabricated using three different glazing treatments: unglazed, glazed only on the outside, and glazed on both surfaces. The changes in microstructure and permeability characteristics of onggi containers were examined after fermentation of soy sauce. The effect of repeated use of onggi containers on the fermentation was analyzed by the contact between an aqueous model solution and the onggi containers used once for soy sauce fermentation. The levels of reducing sugar and free amino acids produced from the dissolved starch and protein, respectively, in the solution were compared between the new and reused onggi containers. The moisture permeance and gas permeabilities of the onggi jars were progressively reduced with continuing use for soy sauce fermentation, probably due to clogging of micropores by solid materials. After having been used once for fermentation, the microbial cells and/or enzymes immobilized on the surface or in the micropores of the onggi containers seemed to contribute to accelerating the hydrolytic reactions of starch and protein.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.184-191
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• 2004

To investigate bacteria with algalytic activities against Anabaena cylindrica when water blooming occurs and to study enzyme profiles associated with alga-lytic activity, various bacterial strains were isolated from surface waters and sediments in eutrophic lakes or reservoirs in Korea. Among 178 isolates, only nine isolates exhibited lytic abilities against A cylindrica on the agar plates, and then the isolate AK-13 was selected as the strongest in lysing the cyanobacterium A. cytindrica. The strain AK-13 was characterized and identified as Sinorhizobium sp. based on fatty acid methyl ether profiles and 16S rDNA sequence. According to the results of the enzyme assays, in the strain An-13 of Sinorhizobium sp., alginase, amylase, proteinase (caseinase and gelatinase), carboxymethyl-cellulase (CMCase), laminarinase, and lipase was produced, namely CMCase, laminarinase and protease were highly active. None of glycosidase was produced. Therefore, enzyme systems of Sinorhizobium sp. AK-13 were very complex to degrade cell walls of A. cylindrica. The peptidoglycans of A. cylindrica mat be hydrolyzed and metabolized to a range of easily utilizable monosaccharides or other low molecular weight organic substances by Sinorhizobium sp. AK-13.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.2
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• pp.205-213
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• 2000

This study investigated the effect of mixing protease and lipase on detergency. The detergency of protein soiled, oil soiled and protein-oil soiled cloths and the relative hydrolytic activity of enzymes were examined. The protease-lipase added detergent solution was most effective for the removal of protein in protein-oil soiled cloths. This is because the lipase removed the protein that was physically bound to oil as well as the protease removed the protein. The protease added detergent solution was second effective, the lipase added detergent solution was third effective, and the detergent solution without protease and lipase was the least effective. The protease-lipase added detergent solution was also most effective in the oil removal from protein-oil soiled cloths. Unlike in protein removal, however, the protease added detergent solution was more effective in oil removal than the lipase added detergent solution. This is because the removal of oil bound to protein by protease was more effective than the removal of oil by lipase. In soiling-washing cycles, however, the effects of lipase increased, and as a result, the detergency of protease added detergent solution and the lipase added detergent solution became similar.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.307-314
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• 2021

Pepper (Capsicum annuum L.) is an important agricultural crop worldwide. Recently, Colletotrichum scovillei, a member of the C. acutatum species complex, was reported to be the dominant pathogen causing pepper anthracnose disease in South Korea. In the present study, we isolated bacterial strains from rhizosphere soil in a pepper field in Gangwon Province, Korea, and assessed their antifungal ability against C. scovillei strain KC05. Among these strains, a strain named BS1 significantly inhibited mycelial growth, appressorium formation, and disease development of C. scovillei. By combined sequence analysis using 16S rRNA and partial gyrA sequences, strain BS1 was identified as Bacillus velezensis, a member of the B. subtilis species complex. BS1 produced hydrolytic enzymes (cellulase and protease) and iron-chelating siderophores. It also promoted chili pepper (cv. Nockwang) seedling growth compared with untreated plants. The study concluded that B. velezensis BS1 has good potential as a biocontrol agent of anthracnose disease in chili pepper caused by C. scovillei.

• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.88-93
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• 2022

In this study, silkworms fed Cudrania tricuspidata leaves were powdered, and hydrolytic enzymes, including viscozyme, papain, and flavourzyme, were added to verify the functionality of the different mixtures. In the general component analysis, the C. tricuspidata silkworm (CS) group exhibited higher crude protein and ash content than did the other groups, and the enzyme-treated groups exhibited higher carbohydrate content than the CS group. The DPPH and ABTS radical scavenging activities were significantly higher in the CS treated with viscozyme (CSV) and the CS treated with viscozyme/flavourzyme (CSVF) than in the other groups, with the CSV group showing the highest reducing power. ACE inhibitory activity was significantly higher in the CS treated with visocozyme/papain (CSVP) than in the CS group. In conclusion, rather than using powdered silkworms fed C. tricuspidata leaves, it would be more effective to use hydrolysates from C. tricuspidata silkworms as raw materials for functional foods.