• Korean Journal of Microbiology
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• v.18 no.2
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• pp.59-66
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• 1980

Two strains S-P and S-P-2, both Streptomyces sp., have been isolated and were found to have relatively high specific enzyme activity compared to other organisms reported. The specific activity of the enzyme produced from these two strains were 0.25 and 0.2 international units respectively. The productivity of the enzyme achieved was about 50 IU/l/hr. Glucose isomerase form these strains was found to be stable under the temperature of heat treatment (at $65^{\circ}C$) for fixation of enzyme inside the dell. This organism has an advantage in that it did not require toxic metalic ion for enzyme activity and could utilize xylan in leu of xylose as an inducer. The optimal temperature and pH of enzymatic reaction purpose of using these data for the optimal operation and designing of enzyme reactor system. The reaction mechanism was found to follow the single substrate reversible reaction kinetics. The kinetic constants determined experimentally are : $K_{mf}=0.33M,\;K_{mb}=1.0M,\;V_{mf}=0.88{\mu}mole\;per\;min.,\;V_{mb}= 2.96{\mu}mole\;per\;min.\;and\;K_{eq}=0.74.

• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.226-234
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• 2006

Disturbance of antioxidant system is very common in chronic alcoholics and herbal or natural products with antioxidant activity have been used for its treatment. This study was to investigate the effect of Vitis vinifera extract(V), Schisandra chinensis extract(S), Taraxacum officinale extract(T), Gardenia jasminoides extract(G), Angelica acutiloba extract(A) and Paeonia japonica extract(P), and their combinations on the antioxidant and ethanol oxidation system. Male Sprague-Dawley rats were subjected to Lieber-DeCarli ethanol liquid diet(ED) and were then given different herbal extract mixtures for 6 weeks including VST(V 100+S 150+T 150mg/kg/day), VSG(V 100+S 150+G 150mg/kg/day), VTG(V 100+T 150+G 150mg/kg/day), and VAP(V 100+A 150+P 150mg/kg/day). When the activity of alcohol dehydrogenase(ADH) and acetaldehyde dehydrogenase(ALDH) were compared between ED only group and herbal extracts treatment group, the differences were statistically significant. Phase I and II(glutathione-S-transferase, phenol sulfatransferase) enzyme activities were found to be significantly higher in the VAT treatment group compared to the ED group. Herbal extracts not only repressed the ethanol-induced elevation of malondialdehyde level, but also protected against ethanol-induced decrease in glutathione content, glutathione reductase, glutathione peroxidase, catalase and superoxide dismutase activities. The administration of the herbal extracts was found to be effective in eliminating lipid-peroxides induced by long-term consumption of alcohol by activating various enzyme systems and physiological active compound formation system. After a chronic consumption of alcohol, Angelica Radix protected the liver via activating the ethanol-metabolism enzyme system, and Paeoniae Radix via activating the ethanol-metabolism enzyme and the phase I, II-metabolism enzyme system. Taraxaci Herba was also effective in liver protection via activating the ethanol-metabolism enzyme system and the phase I, II-metabolism enzyme system, Gardeniae Fructus via activating the phase II-metabolism enzyme system and the anti-oxidation system enzyme, and Schisandra Fructus and a grapestone via activating the anti-oxidation system. Our data suggest that these herbal extracts may be useful as a health functional food or new drug candidate for fatty liver and hepatotoxicity induced by chronic alcohol consumption.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.964-972
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• 1994

The 4.3-kb gene coding for L-lactate dehydrogenase of Bacillus stearothermophilus has been subcloned and expressed in E. coli cells. The enzyme was purified 200-fold with 25% yield by heat treatment , DEAE-Sephadex, and NAD++ -Sepharose CL-4B affinity chromatography followed by gel filtration through Sephadex G-200 . The molecular weight of the purfied enzyme was estimated to be about 35, 000 and 140, 000 on SDS-polyacrylamide gel electrophoresis and gel filtration, respectively. indicating that the enzyme is composed of four identical subunits. THe enzyme for pyruvate reduction and lactate oxdiation was stable at 60 and 75$^{\circ}C$ for 30 min, and the optimal temperatures for both reactions were 60 and 7$0^{\circ}C$, respectively. The enzyme had an optimal pH at 5.5 and 8.5 in pyruvate reduction and lactate oxidation, respectively. The pH stability of enzyme of pyruvate reduction was table between pH 5 and 7. more than 90% of enzyme activity was lost at 1mM FeSO4 and p-chloromercuribonzoate. The maximal activation of the enzyme was obtained with 0.8mM fructose 1, 6-bisphosphate.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.1
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• pp.54-60
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• 2001

A study was conducted to assess the nutritive value of two diets based on a low-energy variety of wheat, RAC C1 and their effects on intestinal mucosal structure and function in broiler chickens. The diets were fed with or without microbial enzyme supplement to male and female broiler chickens. The digesta viscosity was reduced (p<0.001) through supplementation with a microbial enzyme in male and female chicks. Enzyme supplementation also improved the dietary apparent metabolizable energy content (p<0.001) and had slight but non-significant positive effects on chick growth and feed conversion ratio. Intestinal mucosal structure and enzyme function were not affected by microbial enzyme supplement. Male chicks consumed more feeds (p<0.001), attained higher final body weight (p<0.001) and were more efficient at feed utilization (p<0.01) than the female chicks. Except for duodenal villus surface area and ileal protein content, intestinal mucosal structure and enzyme activities were similar between the two sexes and dietary treatment groups. The study showed an improvement in the nutritive value of the diets in the presence of the microbial enzyme supplement.

• Journal of Microbiology and Biotechnology
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• v.5 no.4
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• The Journal of Korean Medicine
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• v.18 no.1
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• pp.218-237
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• 1997

In order to investigate the antihypertentive effects and its mechanism of the Siegesbeckia pubescens aqua-acupuncture treatment, experiments were performed on immediate and continuous antihypertensive effects, vasodilatation-autonomic nerve block, diuretic activity, and angiotensin converting enzyme inhibitory activity. The results were as follows; 1. Acupuncture treatment group showed significantly immediate antihypertensive effects in 4 hours after treatment. Normal saline aqua-acupuncture treatment group showed significantly immediate antihypertensive effects in 2, 4 and 6 hours after treatment. Siegesbeckia pubescens aqua-acupuncture treatment group showed significantly immediate antihypertensive effects in 30 minutes, 1, 2, 4 and 6 hours after treatment. 2. Siegesbeckia pubescens aqua-acupuncture treatment group showed significantly continuous antihypertensive effects in 6, 8, 9 and 10 days after treatment. 3. Siegesbeckia pubescens aqua-acupuncture extract solution showed significantly vasodilatatory and sympathetic nerve block effects with concentration of $10^{-6},\;10^{-5},\;10^{-4},\;10^{-3}g/m{\ell}$. 4. Oral administration group of the Siegesbeckia pubescens aqua-acupuncture extract solution didn't show no significantly diuretic effects. 5. Siegesbeckia pubescens aqua-acupuncture extract solution showed 28.8% angiotensin converting enzyme inhibitory activity.

• KSBB Journal
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• v.24 no.6
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• pp.579-583
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• 2009

The effects of cell lytic enzyme treatment on total phenolic content, antioxidant and antityrosinase activities of lotus leaf were investigated. The dried lotus leaves were hydroyzed by cell lytic enzymes such as Promozyme, Ceremix, Pectinex, Ultraflo, Celluclast, Pentopan, Tunicase, Viscozyme at their optimum pHs (pH 5-8) at $50^{\circ}C$ for 4 hrs. Depending on the enzymes used, total phenolic compounds content was measured as $1,079-1,476{\mu}g$/mL, and antioxidant activities and whitening activities were increased by 5~10% and 20%, respectively Among the tested hydrolytic enzymes, Promozyme (pullulanase) was selected as the most suitable enzyme for the extraction of total polyphenol from lotus leaf. The optimal dosage of Promozyme were found to be 1-2% (w/w). By Promozyme treatment, total phenolic compounds content of the lotus extract significantly increased compared to the extraction without enzyme treatment.

• Journal of Ecology and Environment
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• v.40 no.1
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• pp.5-11
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• 2016

Background: As the decomposition of lignocellulosic compounds is a rate-limiting stage in the nutrient mineralization from organic matters, elucidation of the changes in soil enzyme activity can provide insight into the nutrient dynamics and ecosystem functioning. The current study aimed to assess the effect of thinning intensities on soil conditions. Un-thinned control, 20 % thinning, and 30 % thinning treatments were applied to a Larix kaempferi forest, and total carbon and nitrogen, total carbon to total nitrogen ratio, extractable nutrients (inorganic nitrogen, phosphorus, calcium, magnesium, potassium), and enzyme activities (acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, ${\beta}$-glucosaminidase) were investigated. Results: Total carbon and nitrogen concentrations were significantly increased in the 30 % thinning treatment, whereas both the 20 and 30 % thinning treatments did not change total carbon to total nitrogen ratio. Inorganic nitrogen and extractable calcium and magnesium concentrations were significantly increased in the 20 % thinning treatment; however, no significant changes were found for extractable phosphorus and potassium concentrations either in the 20 or the 30 % thinning treatment. However, the applied thinning intensities had no significant influences on acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, and ${\beta}$-glucosaminidase activities. Conclusions: These results indicated that thinning can elevate soil organic matter quantity and nutrient availability, and different thinning intensities may affect extractable soil nutrients inconsistently. The results also demonstrated that such inconsistent patterns in extractable nutrient concentrations after thinning might not be fully explained by the shifts in the enzyme-mediated nutrient mineralization.

• Applied Microscopy
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• v.15 no.1
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• pp.13-30
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• 1985

This study was undertaken to investigate the effect of lead on organisms. Mice received 15mg or 30mg of lead acetate per kg body weight every day for 1, 2 or 3 weeks, and the livers and kidneys were removed 24h after repeated injections. The livers and kidneys were used as sources for measurement of enzyme activities and for observation of alterations in ultrastructure. It was observed that body weights of mice treated with lead acetate were decreased when compared with those before treatment. This decrease in body weight was proportional to dose. The enzyme activities of succinate and malate dehydrogenases of experimental group that was treated with lead acetate for 1 week were nearly unchanged when compared with controls, but the enzyme activities of experimental group that was treated with lead acetate for 2 or 3 weeks were lower than those of controls. Changes in the enzyme activities were dependent on, but were not proportional to dose. Histologic examination of livers and kidneys after lead treatment showed that lead compound was accumulated and damaged in nucleus and mitochondria mainly. It was also observed that intranuclear inclusion bodies were formed only in epithelial cell of kidney proximal tubule after lead treatment. The overall changes in the ultrastructure were much greater in the livers than in the kidneys. From the above results, it nay be possible to conclude that the lead results in the decrease in body weight, reduction in the succinate dehydrogenate and malate dehydrogenase activities, and damages in the ultrastructure of kidney and liver in mouse. The presence of intranuclear inclusion bodies only in the kidney implies that these bodies protect the kidney from lead toxicity to some extent.

• Archives of Pharmacal Research
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• v.19 no.3
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• pp.201-206
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• 1996

Nitric oxide (NO) is thought to be a second messenger involved in secretion. Upon stimulating pancreatic acinar cells with cholecystokinin-pancreozymin (CCK-PZ), NO formation has been shown to be associated with increased levels of cGMP (Seo et al., 1995). To elucidate the signaling pathway of VIP-induced enzyme secretion, we investigated the NO and cGMP synthesis steps as potential steps where two signal pathways triggered by CCK-PZ and VIP interact. The results obtained in this work provide evidence that increase in pancreatic enzyme secretion by treatment with VIP has no relationship with NOS activity and cGMP level. This conclusion was derived from the following findings that VIP treatment of rat pancreatic tissue increased amylase release as well as protein output in a dose- and time-dependent manner, whereas NOS activity and cGMP synthesis were not affected by VIP treatment as monitored by NOS activity assay and determining cGMP level, which was further confirmed by a NOS-inhibitor study. Consequently, CCK-PZ or VIP increases enzyme secretion in rat pancreatic tissue, but the two hormones are different in their mode of action. Together the results suggest that signaling pathway of VIP-induced enzyme secretion might either bypass the NO and cGMP synthesis steps or lie on a distinct pathway from CCK-PZ-induced pathway.