• Environmental Engineering Research
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• 제22권2호
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• pp.224-229
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• 2017

Zinc oxide nanoparticles (ZnO NPs) have been used as additives in a variety of consumer products. While these particles may enter the environment, only a limited number of studies have investigated the effects of ZnO NPs on soil exoenzymes. Here, we investigate the long-term effects of ZnO NPs at concentrations of 50 and 500 mg/kg on the activities of six soil exoenzymes in planted soils: Dehydrogenase, fluorescein diacetate (FDA) hydrolase, urease, acid phosphatase, arylsulfatase, and ${\beta}-glucosidase$. Significant effects were observed at one or more time points for all enzymes except for FDA hydrolase. These effects included both decreases and increases in enzyme activity. Our results suggest that ZnO NP treatments of 50 and 500 mg/kg can adversely affect soil enzymes, particularly acid phosphatase and urease, and thus, these data may have implications for phosphorous and nitrogen cycles in the soil.

• 생약학회지
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• 제31권2호
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• pp.228-234
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• 2000

Effects of Houttuynia cordata on the level of lipid peroxide and the enzyme activities of the liver were investigated in bromobenzene-induced rats. Lipid peroxide content in liver was increased by bromobenzene. It was decreased when the methanol extract from the aerial parts of H. cordata was treated to the rat. The methanol extract reduced the activities of aminopyrine N-demethylase and aniline hydroxylase that increased by bromobenzene, however did not affect glutathione S-transferase activity. The methanol extract recovered the activity of epoxide hydrolase activity that decreased significantly by bromobenzene. We suggest that under our experimental conditions the extract might play an important play in the prevention of hepatotoxicity by reduction of aminopyrine N-demethylase and aniline hydroxylase activities as well as enhancement of epoxide hydrolase activity. Six phenolic compounds have been isolated from H. cordata and identified by means of spectral analysis as protocatechuic acid, quercetin, apigenin, afzelin, hyperoside and quercitrin.

• 미생물학회지
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• 제32권1호
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• pp.40-46
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• 1994

Polychlorinaed biphenyls(PCBs) 와 biphenyl을 분해하는 Pseudomonas sp. DJ-12에서는 그 초기 분해과정에 pcb ABCD 유전자들이 관여하고 있음이 밝혀졌다. 그 중 pcbCD와 pcdD 유전자를 E. coli XL1-Blue에 클로닝하여 E. coli CU103 과 CU105 균주를 각각 제조하였다. E. coli CU103은 2,3-dehydroxybuphenyl dioxygenase(2,3-DHBP)와 meta-cleavage compound(MCP) hydrolase를 생성하여 2,3-dihydroxybiphenyl을 benzoate로 변환시켜 주었다. E. coli CU1 과 CU103 에서 pcbC 유전자의 산물인 2,3-DHBP dioxygense의 활성도는 Pseudomonas sp. DJ-12에서 보다 약 17배 높았으며, E. coli CU105에서 pcbD의 산물인 MCP hydrolase는 약 3배 더 높게 나타났다.

• 생명과학회지
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• 제18권11호
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• pp.1617-1624
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• 2008

키틴과 그 탈아세틸화된 형태인 키토산은 지구 상에 가장 풍부하게 존재하는 바이오매스의 하나이다. 키틴과 키토산은 항균활성, 면역증강, 중금속 흡착 등 다양한 생리활성을 보이고 있으며 식품, 의약품, 환경산업 등에서 다양하게 응용되고 있다. 이러한 키틴/키토산을 가수분해하는 효소들과 그 3차구조, 유전자들이 세균, 고세균, 진핵생물등 모든 생물종에서 보고되어 왔다. 탄수화물을 가수분해하는 효소들은 그 아미노산 서열에 따라 CAZy (Carbohydrate Active Enzymes) 데이터베이스에 분류되었는데 흥미롭게도 최근까지 키틴가수분해효소와 키토산가수분해효소들은 14개의 glycosyl hydrolase (GH) family들로 분류되어 있다(GH2, GH5, GH7, GH8, GH18, GH19, GH20, GH46, GH48, GH73, GH75, GH80, GH84, GH85). 본 총설에서는 새로운 유전자원를 찾기위한 한 방편으로서 최근에 새롭게 분류된 glycosyl hydrolase family의 분류법에 따라 각각의 GH family에 속하는 키틴/키토산가수분해효소의 종류 및 구조, 그리고 그 효소적 특징에 대하여 논하고자 한다.

• 한국어병학회지
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• 제27권1호
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• pp.25-33
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• 2014

Anisakis simplex sensu stricto와 A. pegreffii의 3기 유충과 4기 유충에서 얻은 excretory-secretory (ES) products 및 somatic extracts의 가수분해효소 활성을 API ZYM kit를 이용하여 비교하였다. Esterase 그룹의 가수분해효소 중 acid phosphatase는 A. simplex (s.s.)와 A. pegreffii 모두에서 높은 활성을 나타냈으며, esterase (C 4)의 경우 somatic extracts에서만 가수분해효소 활성이 나타났는데 A. simplex (s.s.)가 A. pegreffii와 비교하여 3기와 4기 유충 모두에서 2배 가량 높은 활성을 나타냈다. alkaline phosphatase, acid phosphatase 그리고 naphthol-AS-BI-phosphohydrolase의 경우 A. simplex (s.s.)와 A. pegreffii 모두 3기 유충보다 4기 유충에서 더 높은 가수분해효소 활성이 확인되었다. Aminopeptidase 그룹의 가수분해효소 활성은 leucine arylamidase에서 관찰되었는데, somatic extracts의 경우 A. pegreffii 보다 A. simplex (s.s.)에서 가수분해 효소 활성이 두 배 가량 높게 확인되었으며, 대부분의 다른 효소들에서는 활성이 거의 나타나지 않았다. Glycosidase 그룹의 가수분해효소 활성은 N-acetyl-${\beta}$-glucosaminidase, ${\alpha}$-mannosidase 그리고 ${\alpha}$-fucosidase에서 확인되었는데, A. simplex (s.s.) 보다 A. pegreffii에서 높은 가수분해효소 활성을 확인할 수 있었으며, 대부분 4기 유충보다 3기 유충에서 더 높은 가수분해효소 활성이 확인되었다. 이러한 아니사키스속 선충의 종과 유충단계에 따른 가수분해 효소의 활성 차이는 선충의 성장, 탈피, 소화, 섭이 등의 대사과정의 차이에 기인한 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제17권6호
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• pp.905-912
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• 2007

A novel ${\beta}-glucosidase$ gene, bglA, was isolated from uncultured soil bacteria and characterized. Using genomic libraries constructed from soil DNA, a gene encoding a protein that hydrolyzes a fluorogenic analog of cellulose, 4-methylumbelliferyl ${\beta}-D-cellobioside$ (MUC), was isolated using a microtiter plate assay. The gene, bglA, was sequenced using a shotgun approach, and expressed in E. coli. The deduced 55-kDa amino acid sequence for bglA showed a 56% identity with the family 1 glycosyl hydrolase Chloroflexus aurantiacus. BglA included two conserved family 1 glycosyl hydrolase regions. When using $p-nitrophenyl-{\beta}-D-glucoside$ (pNPG) as the substrate, the maximum activity of the purified ${\beta}-glucosidase$ exhibited at pH 6.5 and $55^{\circ}C$, and was enhanced in the presence of $Mn^{2+}$. The $K_m\;and\;V_{max}$ values for the purified enzyme with pNPG were 0.16 mM and $19.10{\mu}mol/min$, respectively. The purified BglA enzyme hydrolyzed both pNPG and $p-nitrophenyl-{\beta}-D-fucoside$. The enzyme also exhibited substantial glycosyl hydrolase activities with natural glycosyl substrates, such as sophorose, cellobiose, cellotriose, cellotetraose, and cellopentaose, yet low hydrolytic activities with gentiobiose, salicin, and arbutin. Moreover, BglA was able to convert the major ginsenoside $Rb_1$ into the pharmaceutically active minor ginsenoside Rd within 24 h.

• 한국수산과학회지
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• 제43권5호
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• pp.428-436
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• 2010

Sea-urchins (Anthocidaris crassispina) are widely distributed in the East Sea of Korea. The aim of this study was to evaluate the hepatoprotective effects of sea-urchin roe on bromobenzene (BB)-induced liver damage in rats. The antioxidative and detoxifying properties of sea-urchin roe in BB-poisoned rat liver was examined by chemical analysis of serum aminotransferase (AST, ALT), glutathione S-transferase (GST), $\gamma$-glutamylcystein synthetase, glutathione reductase, epoxide hydrolase, amino-N-demethylase (AD), aniline hydrolase (AH) enzyme activity, as well as lipid peroxide and glutathione contents. Sea-urchin roe inhibited the increase of serum AST, ALT enzyme activity. Increasing lipid peroxide contents and AD and AH activities were significantly decreased in ethanol extract of sea-urchin roe. GST, $\gamma$-glutamylcystein synthetase, glutathione reductase and epoxide hydrolase enzyme activities increased in sea-urchin roe-fed group, compared with the BB-treated group. These results suggest that sea-urchin roe facilitates recovery from liver damage by enhancing antioxidative defense mechanisms and hepatic detoxication metabolism.

• Preventive Nutrition and Food Science
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• 제11권2호
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• pp.140-145
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• 2006

Seventy eight bacterial strains were isolated from several jeotgals using MRS and M 17 agar media. The probiotic properties such as tolerance of extreme growth condition, production of antimicrobial compound, production of hydrogen peroxide, and enzymatic activity of bile salt hydrolase were investigated. DHK 4, 10, 21 and 74 strains showed_a strong tolerance property against extreme conditions such as low pH and 0.5% oxgall-supplemented medium. DHK 10 and 47 strains produced hydrogen peroxide on TMB agar plate. DHK 8 and 10 strains produced antimicrobial compounds onto MRS agar against E. facalis. DHK 4, 6, 21, 29, 33, 63 and 87 strains had high activities of bile salt hydrolase. Especially, DHK 10 displayed a strong probiotic candidate; the abilities to produce the antimicrobial compound, hydrogen peroxide, and bile salt hydrolase. All these strains are assumed to be useful probiotic candidates. Among 78, twenty seven strains which have probiotic properties were tentatively identified by 16S rRNA sequencing. Among them, 7 Lactobacillus spp., 6 Leuconosotoc spp., 2 Weisella spp., 1 Pediococcus sp., 1 Staphylococcus sp., 1 Enterococcus sp. and 2 Streptococcus spp. were tentatively identified.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.365.2-365.2
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• 2002

S-Adenosylhomocysteine hydrolase (SAH) catalyzes the hydrolysis of S-adenosylhomocysteine to adenosine and L -homocysteine and has been an attractive target for the development of broad spectrum antiviral agents. Neplanocin A and 9-(dihydroxycyclopent-4' -enyl)adenine (DHCeA) have been known to inhibit SAH by cofactor (NAD＋) depletion mechanism and their inhibition is reversed by the addition of NAD＋ or dialysis. (omitted)

• 대한한의학회지
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• 제19권1호
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• pp.49-65
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• 1998

Holotrichia was tested for the effects on damages of liver tissue induced by bromobenzene. Holotrichia was treated firstly into samples, and then bromobenzene intoxicated animal models were set with them. In vitro, the level of lipid peroxide in tissue of liver proportinally decreased with the level of concentration of extract prepared from Holotrichia It was much more decreased, when lipid peroxidation was induced with ferrous iron ($Fe&{+2}$). In vivo, after the extract was administered to the animal model for twenty days, the level of lipid peroxide in liver decreased compared to that of bromobenzene-treated group. The enzyme activities of epoxide hydrolase and glutathione S-transferase in liver highly increased in Holotrichia pre-medicating group compare with the group treated with only bromobenzene. And we can get the same results in the enzyme activities of superoxide dismutase, catalase and glutathione peroxidase. The level of glutathione followed by Holotrichia pre-medicationg administration, increased as highly as normal group in compare with the group treated with only bromobenzene. Also, the enzyme activities of AL T, AST and $\{gammer}-GTP$ in liver considerably decreased. In conclusion, Holotrichia recovers the damage of liver due to bromobenzene intoxication by the increased activities of lipid peroxidation and bromobenzene scavenging enzymes.