• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.822-829
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• 2007

A gene coding for phosphoketolase, a key enzyme of carbohydrate catabolism in heterofermentative lactic acid bacteria(LAB), was cloned from a Lactobacillus paraplantarum C7 and expressed in Escherichia coli. The gene is 2,502 bp long and codes for a 788-amino-acids polypeptide with a molecular mass of 88.7 kDa. A Shine-Dalgarno sequence(aaggag) and an inverted-repeat terminator sequence are located upstream and downstream of the phosphoketolase gene, respectively. The gene exhibits an identity of >52% with phosphoketolases of other LAB. The phosphoketolase of Lb. paraplantarum C7(LBPK) contains several highly conserved phosphoketolase signature regions and typical thiamine pyrophosphate(TPP) binding sites, as reported for other TPP-dependent enzymes. The phosphoketolase gene was fused to a glutathione S-transferase(GST::LBPK) gene for purification. The GST::LBPK fusion protein was detected in the soluble fraction of a recombinant Escherichia coli BL21. The GST::LBPK fusion protein was purified with a yield of 4.32mg/400ml by GSTrap HP affinity column chromatography and analyzed by N-terminal sequencing. LBPK was obtained by factor Xa treatment of fusion protein and the final yield was 3.78mg/400ml. LBPK was examined for its N-terminal sequence and phosphoketolase activity. The $K_M\;and\;V_{max}$ values for fructose-6-phosphate were $5.08{\pm}0.057mM(mean{\pm}SD)$ and $499.21{\pm}4.33{\mu}mol/min/mg$, respectively, and the optimum temperature and pH for the production of acetyl phosphate were $45^{\circ}C$ and 7.0, respectively.

• 한국식품영양과학회지
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• 제44권5호
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• pp.664-672
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• 2015

녹차 성숙잎으로부터 새로운 면역 활성 다당 소재를 개발할 목적으로 녹차잎을 pectinase로 처리하여 조다당 GTE-0을 분리하고 이들의 면역증진 활성과 화학적 특성에 대해 조사하였다. GTE-0은 중성당 54.9%, 산성당 45.1%로 이루어져 있었으며, 구성당 분석 결과 주로 glucose(14.2%), arabinose(12.2%), rhamnose(11.1%) 및 galactose(7.3%)로 구성되어 있었다. 한편 GTE-0은 비특이적 면역계에 있어 중요한 역할을 담당하고 있는 보체계에 대하여 양성대조군 PSK에 준하는 우수한 활성이 농도 의존적으로 나타났다. 또한 GTE-0을 처리하고 검경 시 형태적으로 구분이 가능한 활성화된 대식세포의 숫자가 증가되는 경향을 보였다. 대식세포의 NO, ROS 및 $H_2O_2$ 생산에 미치는 GTE-0의 효과를 검토한 결과 ROS와 $H_2O_2$는 모두 농도 의존적으로 생산량을 증가시키는 우수한 활성을 나타낸 반면, NO의 생산능은 1,000 mg/mL의 고농도에서보다 오히려 100 mg/mL의 저농도에서 더 우수한 활성을 나타내었다. 또한 GTE-0으로 자극한 대식세포는 무처리 대조군에 비해 IL-6, IL-12 및 TNF-${\alpha}$와 같은 다양한 cytokine들의 생산이 농도 의존적으로 증가되는 경향을 보였다. 대식세포의 식작용 활성을 측정한 결과 무처리 대조군에 비해 GTE-0 100 mg/mL 농도이상 처리하였을 때 우수한 활성을 나타내었다. 또한 활성화된 대식세포의 YAC-1 종양세포주에 대한 치사 활성을 ex vivo로 측정한 결과 100 mg/mL의 농도에서 무처리군 대비 유의적으로 높은 치사 활성을 보였다. 이상의 결과로부터 녹차 성숙잎으로부터 분리된 효소 처리 조다당 GTE-0은 강력한 면역 활성 증진 효과를 갖고 있음을 결론지을 수 있었다.

• Nutrition Research and Practice
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• 제1권3호
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• pp.184-188
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• 2007

The major goal in the treatment of diabetes mellitus is to achieve near-normal glycemic control. To optimize both fasting blood glucose and postprandial glucose levels is important in keeping blood glucose levels as close to normal as possible. ${\alpha}-Glucosidase$ is the enzyme that digests dietary carbohydrate, and inhibition of this enzyme could suppress postprandial hyperglycemia. The purpose of this study was to test the inhibitory activity of methanol extract of Euonymus alatus on ${\alpha}-glucosidase$ in vitro and in vivo to evaluate its possible use as an anti-diabetic agent. Yeast ${\alpha}-glucosidase$ inhibitory activities of methanol extract of E. alatus were measured at concentrations of 0.50, 0.25, 0.10, and 0.05 mg/ml. The ability of E. alatus to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without E. alatus extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast. Plasma glucose levels were measured at 30, 60, 90, 120, 180, and 240 min. Plasma glucose levels were expressed in increments from baseline, and incremental areas under the response curve were calculated. Extract of E. alatus, which had an $IC_{50}$ value of 0.272 mg/ml, inhibited yeast ${\alpha}-glucosidase$ activity in a concentration-dependent manner. A single oral dose of E. alatus extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that E. alatus has an antihyperglycemic effect by inhibiting ${\alpha}-glucosidase$ activity in this animal model of diabetes mellitus.

• 대한의생명과학회지
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• 제21권4호
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• pp.188-197
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• 2015

In this study, we investigated the effect of rice bran water extract fermented with Lactobacillus plantarum Hong (RBLw), on activities of cyclooxygenase-1 (COX-1) and thromboxane $A_2$ synthase (TXAS), thromboxane $A_2$ ($TXA_2$) production associated microsomal enzymes and evaluated its the antiplatelet effect. RBLw, containing 13.5 mg of ferulic acid, dose-dependently inhibited ADP-induced platelet aggregation, and inhibited the production of $TXA_2$, an aggregation molecule. In addition, RBLw directly inhibited COX-1 activity in a dose-dependent manner, but not TXAS activity in platelet microsomal fraction having cytochrome c reductase (an endoplasmic reticulum marker enzyme) activity and expressing COX-1 (72 kDa) and TXAS (60.5 kDa) proteins. These results suggest that RBLw selectively inhibited the activity of COX-1 rather than TXAS to attenuate $TXA_2$ production in ADP-activated platelets. Thus, we demonstrate that RBLw might have direct COX-1 antagonistic function for platelet aggregation-mediated diseases, such as thrombosis, myocardial infarction, atherosclerosis, and ischemic cerebrovascular disease.

• Archives of Pharmacal Research
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• 제21권2호
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• pp.128-134
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• 1998

Nitric oxide synthase, NOS (EC.1.14.13.39), was purified from bovine pancreas over 5,500-fold with a 7.6% yield using 30% ammonium sulfate precipitation, and $2^1$,$5^1$-ADP-agarose and calmodulin-agarose affinity chromatography. The purified bovine pancreatic NOS (bpNOS) showed a single band on SDS-PAGE corresponding to an apparent molecular mass of 160 kDa, whereas it was 320 kDa on non-denaturating gel-filtration. This indicated a homodimeric nature of the enzyme. The specific activity of the purified bpNOS was 31.67 nmol L-citrulline fored/mtn/mg protein and an apparent $K\textrm{m}$ for L-arginine was 15.72 $\mu\textrm{M}$, The enzyme activity was dependent on $Ca^{2+}$ and calmodulin, and to a lesser extent on NADPH, FAD and FMN. $H_4B$ was not required as a cofactor for the activity. In an inhibition experiment with L-arginine analogues, $N^G$-nitro-L-arginine (NNA) had the most potent inhibitory effect on bpNOS, and $N^{G}$, $N^{G1}$-dimethyl-L-arginine (symmetric; sDMA) did not have any inhibitory effect. Immunohistochemical analysis of the bovine pancreas using brain type NOS antibody (anti-bNOS antibody) revealed that acinar cells showed strong immunoreactivity against the antibody.

• 한국수산과학회지
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• 제48권6호
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• pp.888-897
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• 2015

The anti-inflammatory effect of alginate oligosaccharides on LPS-induced RAW 264.7 cells was investigated at different time points (0-60 h). The alginate oligosaccharides were produced by an alginate-degrading enzyme from Shewanella oneidensis PKA1008. The alginate oligosaccharides decreased the production of nitric oxide and proinflammatory cytokines [tumor necrosis factor-${\alpha}$, interleukin (IL)-$1{\beta}$, and IL-6] in a dose-dependent manner. The alginate oligosaccharides showed peak anti-inflammatory activity after 36 h of incubation; at that time point, reduced protein expression of NF-${\kappa}B$ p65, iNOS, and COX-2 was detected. Furthermore, the alginate oligosaccharide treatment reduced the formation of ear edema at 36 h compared to samples examined at 0 h when the oligosaccharides were administered at 50 and 250 mg/kg body weight, as well as dermal thickness and mast cell numbers in a histological analysis. These results suggest that alginate oligosaccharides are a promising anti-inflammatory agent.

• Preventive Nutrition and Food Science
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• 제15권4호
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• pp.267-274
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• 2010

We assessed the effect of Se-methylselenocysteine (MSC) treatment, at a dose of 0.75 mg/rat/day for 1 or 2 weeks, on the activities of antioxidant systems in Sprague-Dawley rat tissues. Significant changes in glutathione and antioxidant enzyme activities, with different patterns among tissues, were evidenced. Glutathione content and its reduction state in the liver, lung, and kidney were elevated upon MSC treatment, whereas they were significantly lowered in the spleen. Among the tissues exhibiting glutathione increase, there were different enzymatic responses: $\gamma$-glutamylcysteine ligase activity, the rate-limiting enzyme in the glutathione synthesis pathway, was increased in the liver, whereas the activities of the enzymes associated with glutathione recycling, namely, glutathione peroxidase, glutathione reductase, and glucose 6-phosphate dehydrogenase, were significantly increased in the lung and the kidney. The superoxide dismutase activity was decreased in all tissues upon MSC treatment, whereas catalase activity was increased in all tissues but the liver. Lipid peroxidation level was transiently increased at 1 week in the lung and the kidney, whereas it was persistently increased in the spleen. The increase was not evident in the liver. The results indicate that the MSC treatment results in an increase in the antioxidant capacity of the liver, lung, and kidney principally via an increase in glutathione content and reduction, which appeared to be a result of increased synthesis or recycling of glutathione via tissue-dependent adaptive response to oxidative stress triggered by MSC. The spleen appeared to be very sensitive to oxidative stress, and therefore, the adaptive response could not provide protection against oxidative damage.

• 한국토양비료학회지
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• 제48권4호
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• pp.262-270
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• 2015

The scientific information between microbial community and chemical properties of reclaimed tidal soil is not enough to understand the land reclamation process. This study was conducted to investigate the relation between chemical properties and microbial activities of soils from reclaimed tidal lands located at south-western coastal area (42 samples from Goheuong, Samsan, Bojun, Kunnae, Hwaong and Yeongsangang sites). Most of the reclaimed soils showed chemical characteristics as salinity soil based on EC. Only $Na^+$ in exchangeable cation was dependent on EC of reclaimed soil, whereas other cations such as $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were independent on EC. The mesophilic bacteria decreased with an increase in EC of soil. Microbial population increased with soil organic content in the range of $0{\sim}10g\;kg^{-1}$ and dehydrogenase activity less than $100{\mu}g-TPF\;g^{-1}h^{-1}$. Microbial population of soils from reclaimed tidal lands was closely related to the microbial community containing hydrolytic enzyme activities of cellulase, amylase, protease, and lipase.

• 생약학회지
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• 제35권4호통권139호
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• pp.283-287
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• 2004

The effect of water extract from Cnidii Rhizoma (CRW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. CRW inhibited the growth of both estrogen-dependent MCF-7 and estrogen-independent MDA-MB-23I human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by CRW at the concentration of 0.5, 1.0 and 5.0 mg/ml. Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of CRW in Raw 264.7 cells. CRW inhibited induction of ornithine decarboxylase by 12-0-tetradecanoylphorbol-13-acetate, a key enzyme of polyamine biosynthesis, which is enhanced in tumour promotion. Therefore, CRW is worth further investigation with respect to breast cancer chemoprevention or therapy.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.109-109
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• 2001

The present study was done to investigate the relationship between Kupffer cells and alteration of cytochrome P-450 (CYP)-dependent drug metabolizing enzyme activities during polymicrobial sepsis. Male rats were subjected to polymicrobial sepsis by cecal ligation and puncture (CLP) followed by fluid resuscitation. The gadolinium chloride (GdC1$_3$, 10 mg/kg), blocker of Kupffer cells, was pretreated intravenously at 48 h and 24 h prior to the induction of CLP. All assay parameters were determined at 24 h after CLP or sham operation. In CLP-treated rats, the mortality rate of animals increased to 50% and serum alanine (ALT) and aspartate aminotransferase (AST) levels also significantly elevated. However, this increase was not suppressed by GdC1$_3$ pretreatment. Microsomal lipid peroxidation markedly increased after CLP operation. This increase was significantly attenuated by pretreatment. Total cytochrome P-450 content and NADPH-cytochrome P-450 reductase activity were not changed after CLP operation, but GdC1$_3$pretreatment reduced total cytochrome P-450 content, The hepatic microsomal CYP 1A1, 1A2, 2Bl and 2El activities in CLP-induced rats were also not significantly different from sham-operated rats. However, GdC1$_3$pretreatment showed a moderate increase in CYP1A1 and 1A2 activities. Our findings suggest that Kupffer cells may be partly responsible for producing hepatocellular dysfunction during sepsis.