• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.79-84
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• 2020

This study investigated the characterization and functionality of Undaria pinnatifida root (UPT) extracts, degraded using a crude enzyme from Shewanella oneidensis PKA1008. To obtain the optimum degrading conditions, the UPT was mixed with alginate degrading enzymes from S. oneidensis PKA 1008 and was incubated at 30℃ for 0, 3, 6, 12, 24, and 48 h. The alginate degrading ability of these enzymes was then evaluated by measuring the reducing sugar, viscosity, pH and chromaticity. Enzymatic extract at 24 h revealed the highest alginate degrading ability and the lowest pH value. As the incubation time increased, the lightness (L ^⁎) also decreased and was measured at its lowest value, 39.84, at 12 hours. The redness and yellowness increased gradually to 10.27 at 6 h and to 63.95 at 3 h, respectively. Moreover, the alginate oligosaccharides exhibited significant anti-inflammatory activity. These results indicate that a crude enzyme from S. oneidensis PKA 1008 can be used to enhance the polysaccharide degradation of UPT and the alginate oligosaccharides may also enhance the anti-inflammatory effect.

• BMB Reports
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• 제42권1호
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• pp.47-52
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• 2009

Alanine racemase catalyzes the interconversion of L-alanine and D-alanine and plays a crucial role in spore germination and cell wall biosynthesis. In this study, alanine racemase produced by Bacillus anthracis was expressed and purified as a monomer in Escherichia coli and the importance of lysine 41 in the cofactor binding octapeptide and tyrosine 270 in catalysis was evaluated. The native enzyme exhibited an apparent $K_m$ of 3 mM for L-alanine, and a $V_{max}$ of $295\;{\mu}moles/min/mg$, with the optimum activity occurring at $37^{\circ}C$ and a pH of 8-9. The activity observed in the absence of exogenous pyridoxal 5'-phosphate suggested that the cofactor is bound to the enzyme. Additionally, the UV-visible absorption spectra indicated that the activity was pH independece, of VV-visible absorption spectra suggests that the bound PLP exists as a protonated Schiff's base. Furthermore, the loss of activity observed in the apoenzyme suggested that bound PLP is required for catalysis. Finally, the enzyme followed non-competitive and mixed inhibition kinetics for hydroxylamine and propionate with a $K_i$of $160\;{\mu}M$ and 30 mM, respectively.

• Journal of Preventive Medicine and Public Health
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• 제48권3호
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• pp.151-169
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• 2015

Objectives: The deleterious effects of air pollution on various health outcomes have been demonstrated. However, few studies have examined the effects of air pollution on liver enzyme levels. Methods: Blood samples were drawn up to three times between 2008 and 2010 from 545 elderly individuals who regularly visited a community welfare center in Seoul, Korea. Data regarding ambient air pollutants (particulate matter ${\leq}2.5{\mu}m$ [$PM_{2.5}$], nitrogen dioxide [$NO_2$], ozone [$O_3$], carbon monoxide, and sulfur dioxide) from monitoring stations were used to estimate air pollution exposure. The effects of the air pollutants on the concentrations of three liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and ${\gamma}$-glutamyltranspeptidase [${\gamma}$-GTP)]) were evaluated using generalized additive and linear mixed models. Results: Interquartile range increases in the concentrations of the pollutants showed significant associations of $PM_{2.5}$ with AST (3.0% increase, p=0.0052), ALT (3.2% increase, p=0.0313), and ${\gamma}$-GTP (5.0% increase, p=0.0051) levels; $NO_2$ with AST (3.5% increase, p=0.0060) and ALT (3.8% increase, p=0.0179) levels; and $O_3$ with ${\gamma}$-GTP (5.3% increase, p=0.0324) levels. Significant modification of these effects by exercise and alcohol consumption was found (p for interaction <0.05). The effects of air pollutants were greater in non-exercisers and heavy drinkers. Conclusions: Short-term exposure to air pollutants such as $PM_{2.5}$, $NO_2$, and $O_3$ is associated with increased liver enzyme levels in the elderly. These adverse effects can be reduced by exercising regularly and abstinence from alcohol.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.374-379
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• 2003

Four rumen fistulated Murrah buffaloes were used to study the effect of four diets differing in roughage to concentrate ratio on rumen biochemical changes, microbial enzyme profile and in sacco degradability of feed in a $4{\times}4$ Latin Square design. The animals were fed four diets consisting of 80:20, 70:30, 60:40 and 50:50 ratios of wheat straw and concentrate mixtures, respectively. Wheat straw and concentrate mixture were mixed with water (0.6 l/kg feed) and complete feed mixture was offered to the animals at 8:00 h and 16:00 h in two equal parts. The variation in pH of rumen liquor (difference of maximum and minimum during 0-8 h post feeding) increased with increasing level of concentrate mixture in the diet. There was no effect of diet composition on volatile fatty acids, total nitrogen and trichloro-acetic acid precipitable nitrogen in the rumen liquor, but ammonia nitrogen increased with increasing level of concentrate mixture in the ration. Major portions of all fibre degrading enzymes were present in the particulate material (PM) of the rumen contents, but protease was absent in PM fraction. The activities of micro-crystalline cellulase, acetyl esterase and protease increased with increase in the level of concentrate mixture, but the activities of other enzymes (carboxymethylcellulase, filter paper degrading activity, xylanase, $\beta$-glucosidase and $\beta$-xylosidase) were not affected. The in sacco degradability and effective degradability of feeds increased with increasing level of concentrate mixture in the ration.

• The Plant Pathology Journal
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• 제27권2호
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• pp.148-155
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• 2011

Our previous sequence and phylogenetic analyses of the Korean Rice stripe virus (RSV) suggested possible genetic reassortment of RNA segments, but whether this RNA variation contributed to the recent RSV outbreaks in Korea is yet unclear. To further clarify these RSV-RNA segment variations, we developed a reverse transcription-polymerase reaction/restriction enzyme (RT-PCR/RE) analysis-based method. We identified five REs, including DraI, EcoR1, NdeI/AseI, and SpeI, that could differentiate RSV RNA 1-4 subtypes, respectively. Our RT-PCR/RE results provided a clear pattern of RNA reassortment, i.e., different groups of isolates having their RNA segments derived from two to three different RSV ancestors, such as from Eastern and Southwestern Chinese or Japanese M and T isolates. We also found that the migratory small brown planthopper from Eastern China caught by aerial net traps that possesses RSV-RNA3 genotypes corresponds mainly to Eastern China, with a few for Southwestern China based on RT-PCR/RE, sequence and phylogenetic analyses, indicating that RSV populations in Eastern China may also have strong RNA variation. The development of an RE analysisbased method proved a useful epidemiological tool for rapid genotyping and identification of mixed infections by RSV strain and by different subtype.

• 한국동물학회지
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• 제4권1호
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• pp.7-12
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• 1961

1) Respiratory metabolism patterns and its enzyme systems in the gill tissue of the fresh water mussels, Cristaria plicata were investigated through the examination on the effects of respiratory enzyme inhibitors, (KCN, NAF) and succinoxidase assay, while studying the effects of neutral salts (NaCL, KCL, CaCl2) and pH on oxygen consumption of the gill tissue. 2) In the limited concentration of KCL (0.3mM) and NaCl (0.4mM) solutions, oxygen consumption of the intact gill tissue was accelerated, but in CaCl2(0.5mM) solution, it showed no significant effect. The oxygen consumption was gradually decreased at the above concentrations of these limitations. The optimum pH for the respiration of the gill was 7.3. 3)Cyanide in 10-8M solution inhibited 88.8% of the respiration of the intact gill tissue. Methylene blue accelerated the respiration of the noral gill tissue, and slightly but significantly reversed the cyaniide poisoned respiration. 4)Oxygen consumption of the gill homogenate was apparently increased by the mixed addition of succinate, cytochrome c and activators (AlCl3 and CaCl2). This results suggested that succinoxidase system acts on the respiratory pattern of the gil tissue. 5) It was able to recognize that the enolase, which acts on the anaerobic glycolytic system, participated in the tissue respiration of the gill for NaF in 5$\times$10-2 M solution inhibited 55.5% of the respiration of the same intact tissue.

• 한국자원식물학회지
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• 제24권6호
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• pp.712-718
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• 2011

Ginseng (Panax ginseng) is frequently used in Asian countries as a traditional medicine. The major components of ginseng are ginsenosides. Among these, ginsenoside compound K has been reported to prevent the formation of malignancy and metastasis of cancer by blocking the formation of tumor and suppressing the invasion of cancer cells. In this study, ginsenoside $Rb_1$ was converted into compound K, via secreted ${\beta}$-glucosidase enzyme from the Leuconostoc lactis DC201 isolated, which was extracted from Kimchi. The strain DC201 was suspended and cultured in MRS broth at $37^{\circ}C$. Subsequently, the residue from the cultured broth supernatant was precipitated with EtOH and then dissolved in 20 mM sodium phosphate buffer (pH 6.0) to obtain an enzyme liquid. Meanwhile, the crude enzyme solution was mixed with ginsenoside $Rb_1$ at a ratio of 1:4 (v/v).The reaction was carried out at $30^{\circ}C$ and 190 rpm for 72 hours, and then analyzed by TLC and HPLC. The result showed that ginsenoside Rb1 was transformed into compound K after 72 hours post reaction.

• 동의생리병리학회지
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• 제21권3호
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• pp.658-665
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• 2007

Phyllostachys pubescens (Maengiong-Juk), a kind of the bamboo, was reported to have many beneficial pharmacological actions. in this study, of using 70% ethanol extract of Phyllostachys pubescens we investigated its efficacy on angiotensin converting enzyme (ACE) and antioxidant enzyme activities. In addition, vasorelaxant effect was examined in rat aortic rings. The inhibitory effect of ACE activity by Phyllostachys pubescens extract (PPE) was dose-dependently increased by 61.42% at 10mg/ml. PPE relaxed the pre-contracted rat aortic rings with 10$^{-6}$M phenylephrine, showing about 88% at 4.0mg/ml. Sprague Dawley (SD) rats were given different concentrations of PPE mixed in the drinking water for 10 weeks. PPE did not show any difference with control group in blood pressure, body weight (BW) and food intake. However, it revealed the highest total antioxidative effect at dose of 1.0 g/100 g BW in plasma by TEAC assay. Thiobarbituric acid reactive substance (TBARS) and protein carbonyl levels which are markers of tissue peroxidation, were significantly lowed at the same dosage. Furthermore, hepatic antioxidant enzymes such as total superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and catalase activities were also significantly increased by PPE (1.0 g/100 g BW). In conclusion, we suggest that PPE might have antihypertensive effect through increasing antioxidant activities.

• 공업화학
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• 제23권2호
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• pp.164-168
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• 2012

본 연구는 갈조류인 다시마의 당 성분 함량에 대한 분석과 효소 및 유기산 가수분해물을 이용한 생물학적 바이오 에탄올 생산에 대해 연구하였다. HPLC를 이용한 당 성분 분석 결과 alginate가 total sugar의 65.99%로 가장 많은 것으로 확인되었으며, laminaran과 mannitol이 각각 6.24, 27.77%로 나타났다. 1.5% acetic acid를 이용하여 $121^{\circ}C$, 60 min 동안 가수분해 결과 최대 1.874 g/L의 환원당이 생성되었으며, ascorbic acid의 경우 2.0%에서 최대 4.291 g/L의 환원당이 생성되는 것으로 나타났다. Alginate lyase와 laminarinase와 같은 효소를 이용한 가수분해에서 환원당 생성량은 최대 2.219 g/L였다. 다시마 가수분해물을 이용한 에탄올 발효 결과 유기산을 처리했을 때에는 에탄올 생산량이 오히려 감소하는 것으로 나타났으며, alginate lyase와 laminarinase를 혼합처리 했을 때 에탄올 생산량이 1.26 g/L로 가장 높았다.

• 농업과학연구
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• 제45권4호
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• pp.789-797
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• 2018

This study investigated the activity of crude enzymes obtained from Pyrus pyrifolia cv. Shingo on milk proteins. In the milk processing industry, there is an increasing interest in the addition of functional materials to dairy products or functional peptides isolated from milk proteins. First, Pyrus pyrifolia cv. Shingo was separated into core, flesh, and peel regions, and crude enzymes were obtained from the individual regions. The activity of the obtained crude enzymes was measured using casein and gelatin agar. The crude enzyme obtained from the flesh of Pyrus pyrifolia cv. Shingo decomposed gelatin, but the activity of the crude enzymes obtained from the peel and core regions was insignificant. On the other hand, the crude enzymes obtained from the flesh and core regions of Pyrus pyrifolia cv. Shingo had a remarkable enzymatic activity in casein agar. However, the activity of the crude enzyme obtained from the peel region was insignificant. In addition, the crude enzymes obtained from the individual regions were mixed with casein to induce reactions, and the degradation patterns were investigated through electrophoresis and high performance liquid chromatography (HPLC). According to the results, the crude enzymes from Pyrus pyrifolia cv. Shingo degraded milk proteins. Thus, the results of this study can be used in studies on functionality. Additionally, it is expected that the use of pear peels and cores in the milk processing industry would greatly contribute to the reduction of food waste.