• Microbiology and Biotechnology Letters
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• 제23권4호
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• pp.416-424
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• 1995

Mechanism of the cyclodextrin (CD) production reaction by cyclodextrin glucanotransferase (CGTase) using swollen extrusion starch as substrate was investigated emphasizing the structural features of starch granule. The degree of gelatinization was identified to be the most representative structural characteristic of swollen starch. The most suitable degree of gelatinization of swollen starch for CD production was around 63.52%. The structural transformation of starch granule during enzyme reaction was also followed by measuring the changes of the degree of gelatinization, microcrystallinity, and accessible and inaccessible portion to CGTase action of residual swollen starch. The adsorption phenomenon of CGTase to swollen starch was also examined under various conditions. The inhibition mechanism of CGTase by various CDs was identified to be competitive, most severely by a-CD. The mechanism elucidated will be used for development of a kinetic model describes CD production reaction in heterogeneous enzyme reaction system utilizing swollen extrusion starch.

• BMB Reports
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• 제33권4호
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• pp.321-325
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• 2000

Quinone reductase was purified to homogeneity from bovine liver by using ammonium sulfate fractionation, ionexchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene. The apparent Km for 1,4-benzoquinone and azobenzene was 1.64 mM and 0.524 mM, respectively. The reduction of azobenzene by quinone reductase was almost entirely inhibited by dicumarol or Cibacron blue 3GA, potent inhibitors of the mammalian quinone reductase. In the presence of 1.0${\mu}M$ Cibacron blue 3GA, azoreductase activity was lowered by 45%, and almost complete inhibition was seen above 2.0 ${\mu}M$ Cibacron blue 3GA.

• BMB Reports
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• 제31권1호
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• pp.37-43
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• 1998

The catabolic ${\alpha}$-acetolactate synthase was purified to homogeneity from Serratia marcescens ATCC 25419 using ammonium sulfate fractionation, DEAE-Sepharose, Phenyl-Sepharose, and Hydroxylapatite column chromatography. The native molecular weight of the enzyme was approximately 150 kDa and composed of two identical subunits with molecular weights of 64 kDa each. The N-terminal amino acid sequence of the enzyme was determined to be Ala-Gln-Glu-Lys-Thr-Gly-Asn-Asp-Trp-Gln-His-Gly-Ala-Asp-Leu-Val-Val-Lys-Asn-Leu. It was not inhibited by the branched chain amino acids and sulfometuron methyl herbicide. The optimum pH of the enzyme was around pH 5.5 and the pI value was 6.1. The catabolic ${\alpha}$-acetolactate synthase showed weak immunological relationships with recombinant tobacco ALS, barley ALS, and the valine-sensitive ALS isozyme from Serratia marcescens.

• YAKHAK HOEJI
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• 제31권4호
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• pp.197-203
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• 1987

When pyrazinamide is used in the treatment of tuberculosis, the measurement of pyrazinoic acid which is an intermediate metabolite of pyrazinamide in body is required in order to prevent its associated side-effects, especially that of hyperuricemia. Effects of vitamin B$_6$ on pyrazinoic acid metabolism were studied in this experiment. The activity of hepatic pyrazinoic acid oxidizing enzyme in the presence of pyridoxal was powerfully inhibited, and the pattern was competitive inhibition type. Whereas, its enzyme activity was significantly increased by the treatment of pyridoxal, and the characteristics of the increase may include induction of enzyme proteins. As mice received pyrazinoic acid(300mg/kg) after pyridoxal-pretreatment(40mg/kg) once daily for 4 days, the blood level of pyrazinoic acid and uric acid was decreased significantly.

• The Korea Journal of Herbology
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• 제27권3호
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• pp.67-74
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• 2012

Objectives : The present study was designed to investigate effects of Ssanghwa-tang (Shu$\bar{a}$nghu$\bar{a}$-g$\bar{e}$ng) on oxidation/reduction reaction-related and aging-related enzymes $in$ $vitro$. Methods : We performed MTT assay, collagenase inhibition assay, elastase inhibition assay, tyrosinase inhibition assay, DPPH free radical scavenging assay, SOD-like activity and xanthine oxidase (XO) inhibition assay. Results : The 50% ethanol (EtOH) extract of Ssanghwa-tang (SHT) showed 55% inhibition of collagenase activity, and 42% inhibition of elastase activity at 1 mg/ml concentration. Also it's treatment showed 18% inhibition of tyrosinase activity, to relate whitening effect, at the same dose of 50% ethanol extract of SHT. Antioxidant activities were determined by DPPH radical scavenging, XO inhibiting activity and SOD-like activity. These scavenging, XO-inhibiting and SOD-like activities were measured in 80%, 75%, and 28% inhibitions, respectively, at a 1 mg/ml treated dose, compared to those of control. The inhibitory effects of 50% EtOH extract on aging and oxidation-related enzyme activities were higher than those of water extract and 95% EtOH extract. Conclusions : Taken together, our findings suggest that the SHT has potential and applicable benefits for development of cosmetics to have anti-aging (anti-wrinkle and whitening) and anti-oxidation functions.

• Korean Journal of Food Science and Technology
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• 제38권5호
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• pp.691-698
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• 2006

The purpose of this study was to investigate how herb extracts may improve blood circulation. Twenty-six extracts from nine different herbs (marjoram, lavender, dill, rosemary, hyssop, rose, lemon balm, pineapple sage, and echinacea) were evaluated for their anti-hypertensive effects via angiotensin I converting enzyme (ACE) inhibition. Their cholesterol-lowering effects via hydroxy-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibition and their fibrinolytic activity via fibrin-plate method were also evaluated. Both water extraction of rose flowers and 70% EtOH extraction of pineapple sage leaves effectively reduced the ACE activity with inhibition rates of 133.8% and 91.2%, respectively. Similarly, both water and 70% EtOH extracts of rose flowers strongly inhibited the enzymatic activity of HMG-CoA reductase by 48.9% and 80.5%, respectively. Water and 70% EtOH extracts of rose flowers also showed relatively high fibrinolytic activity. Based on these observations, rose flower extracts can be developed as a functional tool for use in the improvement of blood circulation.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2829-2832
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• 2013

• Proceedings of the Korean Environmental Sciences Society Conference
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• 한국환경과학회 2004년도 봄 학술발표회 발표논문집
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• pp.271-273
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• 2004

Enzyme inhibition기술을 이용한 습식 및 건식 kit는 carbmate계 농약의 잔류를 검출하는데 매우 민감하므로, carbmate계 잔류농약을 신속하게 검색할 수 있다. 즉 AChE효소를 이용한 습식 및 건식 kit로 carbamate계 농약을 검출 할 수 있다. 따라서 빠르고 간편하게 carbamate계 농약을 검출하기 위한 습식 kit 및 건식 kit로 상업화 할 수 있다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 한국축산식품학회 2000년도 정기총회 및 제25차 춘계학술발표회
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• pp.96-96
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• 2000

• The Korean Journal of Mycology
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• 제36권2호
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• pp.183-188
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• 2008

A fibrinolytic serine protease was purified from the fruiting bodies of an edible mushroom, Albatrellus confluens. The enzyme had a molecular mass of 30086.41 Da, as measured by MALDI-TOF mass spectrometry. The N-terminal amino acid sequence of the enzyme was Glu-Thr-Val-Thr-Glu-Thr-Thr-Ala -Pro-Trp-Gly-Leu-Ser-Arg-Ile. It displayed optimal activity at $50^{\circ}C$ and within a pH range of $8.0{\sim}10.0$, suggesting that the enzyme is an alkaline protease. The enzyme was stable up to $30^{\circ}C$. The enzyme displayed a strong substrate specificity for the synthetic peptide, N-Suc-Ala-Ala-Pro-Phe pNA. The enzyme activity was completely inhibited by addition of PMSF, indicating that the enzyme is a serine protease. No inhibition was observed following addition of E-64, pepstatin, or EDTA. The activity of the purified enzyme was decreased in the presence $Fe^{2+}$ or $Co^{2+}$, and the enzyme was completely inhibited by addition of $Hg^{2+}$. From these results, we propose that Albatrellus confluens could be used for biofunctional foods development and has potential therapeutic value for the treatment of vascular diseases.