• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.199-204
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• 2001

A Cryptate (221) having a short alcohol pendant (2) was metallated with europium(Ⅲ) in anhydrous condition, and its hydrolytic activity for phosphate esters at neutral pH was examined. While the activity for the phosphate diester and monoester is comparable to that of the parent metal complex [1Eu]3+, its hydrolytic activity towards a phosphate triester is significantly suppressed. Potentiometric titration and luminescence spectroscopic studies for the equilibrium behavior of the complex in solution suggest that a dimer formation through the metal hydroxides as well as the pendant alcohol is likely to happen. The low hydrolytic activity for the triester seems to be associated with the dimer formation.

• Microbiology and Biotechnology Letters
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• v.48 no.1
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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.

• Journal of Microbiology and Biotechnology
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• v.13 no.1
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• pp.57-63
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• 2003

Using fungal (Fusarium solani f. pisi) and bacterial (Pseudomonas mendocina) cutinases, the initial hydrolysis rate of p-nitrophenyl esters was systematically estimated for a wide range of enzyme and substrate concentrations using a 96-well microplate reader. Both cutinases exhibited a high substrate specificity; i.e. a high hydrolytic activity on p-nitrophenyl butyrate (PNB), yet extremely low activity on p-nitrophenyl palmitate (PNP). When compared to the hydrolysis of PNB and PNP by other hydrolases [lipases and esterases derived from different microbial sources, such as bacteria (Pseudomonas cepacia, Psedomonas furescens, Baciilus stearothermophilus), molds (Aspeillus niger, mucor miehei), and yeasts (Candida rugosa, Candida cylindracea)], the above substrate specificity would seem to be a unique characteristic of cutinases. Secondly, the hydrolytic activity of the cutinases on PNB appeared much faster than that of the other hydrolytic enzymes mentioned above. Furthermore, the current study proved that even when the cutinases were mixed with large amounts of other hydrolases (lipases or esterases), the Initial hydrolysis rate of PNB was determined only by the cutinase concentration for each PNB concentration. This property of cutinase activity would seem to result from a higher accessibility to the substrate PNB, compared with the other hydrolytic enzymes. Accordingly, these distinct properties of cutinases may be very useful in the rapid and easy isolation of various natural cutinases with different microbial sources, each of which may provide a novel industrial application with a specific enzymatic function.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.383-389
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• 1990

During the cultivation of Penkillium uerrmulosum in the media containing cellobiose octaacetate (COA), avicel, or KC-flock as an inducer and as a sole carbon source for 21 days, cellulolytic activity and SDS-PAGE pattern of proteins in the culture broth were investigated. Protein concentration and cellulolytic activity were highest in the COA medium. As cultivation period was increased, protein content and avicel hydrolytic activity of culture broth were increased as similar extent but neither $\beta$-glucosidase nor CMC hydrolytic activity was correlated to protein content. When crude proteins from the culture broth were separated on DEAE column by HPLC, distribution of avicel-hydrolytic activities were well correlated with that of major proteins. From those results it was suggested that three major proteins having 60 K, 68 K, and 76 K of Mr. were avicel-hydrolytic enzymes.

• Journal of Preventive Medicine and Public Health
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• v.26 no.1 s.41
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• pp.74-85
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• 1993

To measure the serum succinyl trialanine p-nitroanilide hydrolytic activity as new index of liver function in workers exposed to organic solvents, this study conducted 114 workers in department of shoe-making of shoes factories. The results obtained from this study were as follows : 1. The mean values of serum GOT, GPT, ${\gamma}GT$ in whole workers were $22{\pm}12.32,\;20{\pm}9.05,\;28{\pm}21.35IU/l$, respectively and the mean value of serum STN hydrolytic activity was $0.08{\pm}0.05$. 2. The serum STN hydrolytic activity was significantly higher for male (p<0.05) and there was no difference among the groups of age. 3. There was no difference in the groups by working hours but significant difference in persons who worked over 3 years or were exposed to toluene over 100ppm (p<0.05). 4. The correlation of the exposed dose of toluene and serum GOT, GPT, ${\gamma}GT$ and serum STN hydrolytic activity were statistically significant (r=0.027-0.518). 5. The exposed dose of toluene was most explainable variable and statistically significant among the factors affecting serum STN hydrolytic activity (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.5
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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.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.101-104
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• 2000

An inhibitory activity against ${\alpha}-glucosidase$ was identified in extract of an edible lichen, Umbilicaria esculenta. The inhibitor was very stable retaining above 95% of its original activity when treated with heat, acid and alkaline conditions, and some hydrolytic enzymes. Partially purified inhibitor showed strong inhibition against disaccharide hydrolytic enzymes of mammalian and mold origin, but weak or no inhibition against polysaccharide hydrolytic enzymes except glucoamylase. The inhibitor suppressed elevation of blood glucose level in rats after oral administration of soluble starch or sucrose.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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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.

• Microbiology and Biotechnology Letters
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• v.47 no.1
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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.

• Journal of Plant Biotechnology
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• v.6 no.1
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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.