• 한국미생물·생명공학회지
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• 제48권1호
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• pp.64-71
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• 2020

A total of 262 bacterial strains were isolated from clay minerals, bentonite and zeolite, in Gyeongsangbukdo, Republic of Korea, and their hydrolytic enzyme activities were analyzed. Most of the isolated strains belonged to Micrococcales and Bacillales order. Of strains, 96 strains produced α-amylase activity, 42 strains showed cellulase activity, 111 strains had pectinase activity, and 70 strains showed protease activity. Among them, 177 isolates exhibited one or more of the hydrolytic enzyme activities and in particular Bacillus cereus MBLB1321, B. albus MBLB1326 and KIGAM017, B. mobilis MBLB1328, MBLB1329 and MBLB1330 showed all of the enzyme activities. These results demonstrate the diversity of functional Bacillus species in clay minerals as vital sources for the discovery of industrially valuable hydrolytic enzymes, which have a great commercial prospect in various bio-industrial applications.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.115-120
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• 1997

Penicillium sp.-L4, a causative fungus of rot in citrus fruits, was isolated and its mode of hydrolytic enzyme production was investigated. Carboxymethylcellulase (CMCase), polygalacturonase(PGase), extra- & intra-cellular $\beta$-glucosidase and cellobiase were produced drastically by addition of substrates in minimal media. Production of the hydrolytic enzymes were induced efficiently by cellobiose and cellooligosaccharides which were the products of cellulose hydrolysis, but repressed by addition of mono-saccharide such as glucose, raffinose, galacturonic acid. The relative activity of p-nitrophenyl-$\beta$-D-glucopyranoside(PNPG) hydrolysis was higher than that of cellobiose hydrolysis in extracellular enzymes, and reverse is true in intracellular enzymes. Intact enzyme production of P. sp.-L4 on lemon peel lesion was sequential. $\beta$-Glucosidase and CMCase were produced first and followed by PGase. The enzyme productivities and pH in lesions were coincident with optimal pH of each enzyme activities.

• Journal of Plant Biotechnology
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• 제6권1호
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• pp.63-67
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• 2004

A simple procedure for the extraction of the lipolytic enzyme from rice bran has been developed. High activity of lipolytic enzyme was obtained by first defatting the rice bran to remove lipid components with various extraction conditions. Then, after rove cycles of aqueous extraction, rice bran lipolytic enzyme was purified using micro- and ultrafiltration apparatus. Lipolytic enzyme activity was estimated by its hydrolytic action of tributyrin. The result indicated that the standard activity curve of butyric acid showed that the potential rice bran enzyme is a hydrolytic lipase enzyme. In addition, it showed higher lipolytic activity and specific enzyme activity with further purification by micro- and ultrafiltration. The size of rice bran lipase enzyme was identified through 15 ％ SDS-PAGE. The molecular weight of the rice bran lipase enzyme was 41 kDa.

• 한국식품영양과학회지
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• 제30권5호
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• pp.839-843
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• 2001

감마선 조사를 이용한 장류제품의 미생물 살균 시, 감마선 조사가 장류제품의 효소활성에 미치는 영향을 살펴보기 위한여 된장, 고추장, 간장, 청국장, 메주에 5, 10, 20 kGy의 선량으로 감마선을 조사한 다음 amylase, protease, lipase 그리고 혈전용해효소 활성을 비교하였다. 가수분해효소의 활성은 메주, 청국장, 된장에서 대체로 높았고 간장과 고추장은 상대적으로 낮았다. Amylase, protease, lipase의 효소활성은 10 kGy까지의 감마선 조사에 의하여 영향을 받지 않았으며, 20 kGy의 감마선 조사구에서는 10% 내외의 효소활성 감소가 있었으나 청국장의 protease 활성감소(15%)를 제외하고는 통계적인 유의차가 없었다(p<0.05). 혈전용해효소 활성은 20 kGy까지의 감마선 조사에 의해서 효소활성 변화가 없었다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 추계학술대회
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• pp.299-301
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• 2004

A simple procedure for the extraction of the lipolytic enzyme from rice bran has been developed. High activity of lipolytic enzyme was obtained by first defatting the rice bran to remove lipid components with various extraction conditions. Then, after five cycles of aqueous extraction, rice bran lipolytic enzyme was purified using micro- and ultrafiltration apparatus. Lipolytic enzyme activity was estimated by its hydrolytic action of tributyrin. The result indicated that the standard activity curve of butyric acid showed that the potential rice bran enzyme is a hydrolytic lipase enzyme. In addition, it showed higher lipolytic activity and specific enzyme activity with further purification by micro- and ultrafiltration.

• Asian-Australasian Journal of Animal Sciences
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• 제19권5호
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• pp.684-689
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• 2006

The present study examined the effects of Tween 80 on the attachment and hydrolytic activity of a cellulase enzyme against ball-milled cellulose (BMC), using the whole component (native CBH I) and the catalysis module (core CBH I) of carbohydrolase I purified from Trichoderma viride (Meicelase, Meiji Seika, Tokyo, Japan). The effects were evaluated as protein concentrations in the supernatant after mixing enzyme and substrate with Tween 80 at room temperature. Tween 80 decreased the adsorption of native CBH I and core CBH I onto BMC (p<0.001) and increased the amount of reducing sugars released from BMC by native CBH I (p<0.001). However, Tween 80 did not enhance the hydrolytic activity of core CBH I. Observations using SEM revealed that Tween 80 caused cellulose filter paper to swell and enhanced surface cracks and filaments caused by native CBH I but not by core CBH I. These results suggested that Tween 80 decreases enzyme adsorption to its substrate but enhances enzymatic activity.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2014년도 추계학술대회 및 정기총회
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• pp.47-47
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• 2014

Dokdo island is located in the northeastern part of Ulleungdo, known as volcanic island. In total, 53 fungal isolates were isolated from Dokdo island soil sample, using dilution plate technique. The isolates were identified on the basis of morphological characteristics and rDNA ITS sequence analysis. Out of them, 41 isolates were identified at the level of species. The dominant fungal species and genera included Fusarium spp., Mucor sp., Clonostachys spp., and Trichoderma sp. The % sequence identity (the number of matches/the complete alignment length) values via NCBI BLAST searching of EML-IF9, EML-MF30-1 and EML-DDSF4 represented 97.19% (485/499) with Clonostachys cf. rosea (GenBank accession no. KC313107), 98.33% (472/480) with Metarhizium guizhouense (GenBank accession no. HM055445), and 100% (350/350) with Mortierella oligospora (GenBank accession no. JX976032), respectively. Three species of C. rosea, M. guizhouense and M. oligospora represented new records of fungi from Dokdo island, Korea. The antimicrobial activities of the fungal strains varied with tested. Two isolates (EML-MFS30-1 and EML-IF9) showed antifungal activity against several fungi including Fusarium oxysporum and Rhizotonia solani. Clonostachys rosea (EML-IF9) showed strong hydrolytic enzyme activity. Our results showed that the antagonistic fungi including Clonostachys rosea will be used as potential biocontrol agents for control of fungal diseases.

• 한국미생물·생명공학회지
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• 제47권1호
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• pp.125-131
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• 2019

We have isolated and identified 72 bacterial strains from four bentonite samples collected at the mining areas located in Gyeongsangbuk-do, Republic of Korea, and measured their hydrolytic enzyme (${\alpha}$-amylase, protease, and cellulase) activities to identify the isolates with industrial-use potential. Most of the isolates belonged to the Bacillaceae, with minor portions being from the Paenibacillaceae, Micrococcaceae, and Bacillales Family XII at the family level. Of the strains isolated, 33 had extracellular ${\alpha}$-amylase activity, 30 strains produced cellulase, and 35 strains produced protease. Strain MBLB1268, having the highest ${\alpha}$-amylase activity, was identified as Bacillus siamensis ($0.38{\pm}0.06U/ml$). Bacillus tequilensis MBLB1223, isolated from Byi33-b, showed the highest cellulase activity ($0.26{\pm} 0.04U/ml$), whereas Bacillus wiedmannii MBLB1197, isolated from Zdb130-b, exhibited the highest protease activity ($54.99{\pm}0.78U/ml$). These findings show that diverse bacteria of the Bacillaceae family adhere to and exist in bentonite and are potential sources of industrially useful hydrolytic enzymes.

• 한국식품영양과학회지
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• 제22권3호
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• pp.273-279
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• 1993

박테리아 Bacillus sp. K-295G-7이 생산하는 두유응고효소 I 및 II에 의한 11S globulin (glycinin)의 가수분해 패턴을 조사하였다. 효소 I 과 II에 의한 acidic subunit의 응고시간은 약 4-5 분이었다. 전기 영동의 결과, acidic subunit (A$_3$, M.W=45,000)는 효소반응 2분 이내에 완전히 가수분해되어 분자량 16,000, 20,000의 새로운 band를 형성하였다. 한편 효소 II의 작용으로 약 30,000의 분자량을 가진 분해산물을 생성하였고 효소 I 과 II의 basic subunit 에 대한 가수분해 패턴은 유사하였다.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.189-195
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• 2002

Using Streptomyces sp. YU100 isolated from Korean soil, the fermentative production of phospholipase D was attempted along with its purification and characterization studies. When different carbon and nitrogen sources were supplemented in the culture medium, glucose and yeast extract were found to be the best. By varying the concentration of nutrients and calcium carbonate, the optimal culture medium was determined as 2.0% glucose, 1.5% yeast extract, 0.5% tryptone 0.3% calcium carbonate. During cultivation, the strain secreted most of the phospholipase D in the early stage of growth within 24 h. The phospholipase D produced in the culture broth exhibited hydrolytic activity as well as transphosphatidylation activity on lecithin (phosphatidylcholine). In particular, the culture broth showed 8.7 units/ml of hydrolytic activity when cultivated at $28^{\circ}C$ for 1.5 days. The phospholipase D was purified using 80% ammonium sulfate precipitation and DEAE-Sepharose CL-6B column chromatography, which produced a major band of 57 kDa on a 10% SDS-polyacrylamide gel with purity higher than 80%. The enzyme showed an optimal pH of 7 in hydrolytic reaction, and at pH 4 in a transphosphatidylation reaction. The enzyme activity increased until the reaction temperature was elevated to $60^{\circ}C$. The enzyme was relatively stable at high temperatures and neutral pH, but significantly unstable in the alkaline range. Among the detergents tested as emulsifiers of phospholipids, the highest enzyme activity was observed when 1.5% Triton X-100 was employed. However, no inhibitory effect by metal ions was detected. Under optimized reaction conditions, the purified enzyme not only completely decomposed PC to phosphatidic acid within 1 h, but also exhibited higher than 80% conversion rate of PC to PS by transphosphatidylation within 4 h.