• Korean Journal of Veterinary Research
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• v.59 no.2
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• pp.69-74
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• 2019

Avian malaria is one of the most important general blood parasites of poultry in Southeast Asia. Plasmodium (P.) juxtanucleare causes avian malaria in wild and domestic fowl. This study aimed to identify and characterize the Plasmodium species infecting in Thai native fowl. Blood samples were collected for microscopic examination, followed by detection of the Plasmodium cox I gene by using PCR. Five of the 10 sampled fowl had the desired 588 base pair amplicons. Sequence analysis of the five amplicons indicated that the nucleotide and amino acid sequences were homologous to each other and were closely related (100% identity) to a P. juxtanucleare strain isolated in Japan (AB250415). Furthermore, the phylogenetic tree of the cox I gene showed that the P. juxtanucleare in this study were grouped together and clustered with the Japan strain. The presence of P. juxtanucleare described in this study is the first report of P. juxtanucleare in the Thai native fowl of Thailand.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.542-549
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• 2013

This study was conducted to investigate the chemical properties and functionality of probiotic potato juice fermented by Lactobacillus casei. Free sugar content (especially glucose) of potatoes decreased by fermentation, but organic acid contents increased by fermentation. Although the free amino acid content of Superior juice significantly decreased after fermentation, Haryeong significantly increased after fermentation. ${\gamma}$-Aminobutyric acid, a functional amino acid, was detected at high levels in all samples and slightly decreased with fermentation, but not significantly. The total polyphenol content of potato juice showed insignificant changes in all samples by fermentation. The hydroxyl radical scavenging activity of all samples was more than 90%, and most of the activity was maintained after fermentation. The nitrite scavenging ability of all samples greatly decreased with fermentation; however a SOD-like activity slightly increased with fermentation, except for Haryeong. There was a significant xanthine oxidase inhibitory effect in fresh potato juice (more than 45%) and a low loss by fermentation. From our results, most of the chemical properties and functionality of potato juice are maintained after fermentation, although free sugar content and nitrite scavenging activity decline. Thus probiotic potato juice fermented by lactic acid could be used as a functional beverage.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.261-268
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• 2014

Senescence of Hosta ventricosa flowers was firstly characterized as ethylene-sensitive since the deterioration of the tepal was accompanied by increased endogenous ethylene biosynthesis. The full-length cDNAs and DNAs of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS) and ACC oxidase (ACO) involved in ethylene biosynthesis were cloned from H. ventricosa flowers. The HvACS ORF with 1347 bp and two introns, encoded a polypeptide of 448 amino acids showing 79% homology with that in Musa acuminata. The HvACO ORF contained 957 bp and three introns, encoding a 318-residue polypeptide showing 83% homology with that in Narcissus tazetta. The timing of the induction of HvACS expression was in correspond to the timing of the increase in ethylene production, and that the up-regulation of HvACO transcript was closely correlated with an elevated ethylene production, but underwent a down-regulation in wounded leaves with elevated ethylene emission. The results, together with expression analysis in vegetative tissues, suggested that both HvACS and HvACO were specifically regulated by flower senescence.

• Mycobiology
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• v.42 no.3
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• pp.296-300
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• 2014

We selected Pleurotus ostreatus from among several edible mushrooms because it has high anti-gout xanthine oxidase (XOD) inhibitory activity. The maximal amount of XOD inhibitor was extracted when the Pleurotus ostreatus fruiting body was treated with distilled water at $40^{\circ}C$ for 48 hr. The XOD inhibitor thus obtained was purified by Sephadex G-50 gel permeation chromatography, ultrafiltration, $C_{18}$ solid phase extraction chromatography and reverse-phase high-performance liquid chromatography with 3% of solid yield, and its XOD inhibitory activity was 0.9 mg/mL of $IC_{50}$. The purified XOD inhibitor was a tripeptide with the amino acid sequence phenylalanine-cysteine-histidine and a molecular weight of 441.3 Da. The XOD inhibitor-containing ultrafiltrates from Pleurotus ostreatus demonstrated dose-dependent anti-gout effects in a Sprague-Dawley rat model of potassium oxonate-induced gout, as shown by decreased serum urated levels at doses of 500 and 1,000 mg/kg, although the effect was not as great as that achieved with the commercial anti-gout agent, allopurinol when administered at a dose of 50 mg/kg.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1013-1016
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• 2004

The inhibitory effect of MRPs (Maillard reaction products) on enzymatic browning of taro was investigated. The MRPs prepared by heating glycine and glucose at 9$0^{\circ}C$ for 7 hr exhibited a strong inhibitory effect on taro polyphenol oxidase (PPO). The maximum inhibitory activity of MRPs against taro PPO was detected toward (＋)-catechin, catechol, 4-methylcatechol followed by L-$\beta$-3,4-dihydroxyphenylalanine (L-DOPA) and pyragallol as a substrate. The MRPs synthesized from fructose and glucose with glycine as a amino acid significantly reduced the taro PPO activity. MRPs prepared by higher glycine or glucose concentration showed stronger inhibition against taro PPO. Increasing reaction time of the glycine and glucose promoted the inhibitory effect of MRPs against the PPO activity of taro, whereas the color formation was gradually increased.

• Journal of Life Science
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• v.22 no.11
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• pp.1451-1455
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• 2012

The study was conducted to investigate the effect of Maillard reaction products (MRPs) on enzymatic browning of crown daisy (Chrysanthmum coronarium var. spatiosum). The MRPs prepared by heating various amino acid and sugar at $90^{\circ}C$ caused a strong inhibitory effect on crown daisy polyphenol oxidase (PPO, ${\sigma}$-diphenol oxygen oxidoreductase, EC 1.10.3.1). As the reaction time of the solution containing glycine and glucose increased at $90^{\circ}C$, the production of MRPs was increased, whereas the amounts of glycine and glucose were decreased. Accordingly, the inhibitory effect of crown daisy PPO activity by MRPs was increased as the amounts of synthesized MRPs were increased. The MRPs synthesized from the various amino acids and sugars significantly reduced the PPO activity, particularly MRPs prepared by glutamine and xylose. The Michealis-Menten constant value ($K_m$) of crown daisy PPO with catechol as a substrate was 22.0 mM, and MRPs were a noncompetitive inhibitor against crown daisy PPO.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.853-859
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• 2017

This study was conducted in an effort to investigate the effect of Maillard reaction products (MRPs) on enzymatic browning of burdock and their anti-oxidant activity. The MRPs were prepared by heating glucose and amino acids at $90^{\circ}C$, which served to produce a strong inhibitory effect on burdock polyphenol oxidase. As the reaction time of the solution containing glucose and amino acid increased at $90^{\circ}C$, the production of MRPs increased and intensity of the brown color deepened. When MRPs were prepared by heating at $90^{\circ}C$ for five hours, the absorbance of MRPs from glucose and lysine was 6.44, while those of glucose and glycine was 1.95. The MRPs synthesized from the glucose and lysine also reduced the pH of MRPs from 5.60 to 4.51, but those from glucose and glycine decreased slightly from 5.57 to 5.33. The Michealis-Menten constant value ($K_m$) of burdock PPO with pyrocatechol as a substrate was 16.0 mM, and MRPs were a non-competitive inhibitor against burdock PPO. The anti-oxidant activity of MRPs was measured by evaluating its radical scavenging activities of DPPH radicals, ABTS radicals and reducing power. The color intensity of MRPs produced by lysine and glucose were deeper than that produced by glucose and glycine. It was also found that MRPs produced from glucose and lysine exhibited stronger anti-oxidant properties than those produced by glucose and glycine.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.181-189
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• 2003

We describe here the complete nucleotide sequence and the exon-intron structure of the luciferase gene of the firefly, Pyrocoelia rufa. The luciferase gene of the P. rufa firefly consisted of six introns and seven exons coding for 548 amino acid residues. From the translational start site to the end of last exon, however, the genomic DNA length of the P. rufa luciferase gene from the Korean and Chinese samples spans 1,968 bp and 1983 bp, respectively, and 3 amino acid residues were different to each other. Additionally, we also analyzed mitochondrial cytochrome oxidase I(COI) gene of the Chinese P. rufa fireflies. Analysis of DNA sequences from the mitochondrial COI protein-coding gene revealed 4 mitochondrial DNA sequence-based haplotypes with a maximum divergence of 0.7％. With the 20 P. rufa haplotypes found in Korea, phylogenetic analyses using PAUP and PHYLIP subdivided the P. rufa into three clades, termed clades A and B for the Korean sample, and clade C for the Chinese sample.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.25-30
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• 1978

Among clincal isolates, most strains of Serratia marcescens were belonged to nonpigmented form, and several attempts were undertaken for the rapid and simple identification of these strains. Prodigiosin production of non-pigmented strains was uniformly negative in many kinds of solid media as well as in nutrient agar added with various amino acids and thiamine. On blood agar, colonies of S. marcescens turned gradually to grey or dark color by the lapse of incubation period and this characteristic seems to be able to utilize as an indicator for a primary isolation, and also generally paralleled with the results of dehydration of Tween 80 and lipase activity in soy bean oil medium although these reactions were by no means specific to S. marcescens. In order to rule out these non-specific reactions, other tests such as oxidase and sucrose fermentation are required for the final confirmation of this species.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.288-295
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• 2015

In this study, we investigate the physicochemical characteristics of dried bracken (Pteridium aquilinum Kuhn) harvested in Namhae. The moisture, ash, crude protein and crude lipid content was $10.79{\pm}0.31%$, $6.16{\pm}0.04%$, $33.20{\pm}0.40%$ and $2.45{\pm}0.27%$, respectively. The total mineral (Ca, Fe, K, Mg, Na, Mn) content was $36720.1{\pm}495.7mg/kg$, with K being the highest at $31890.0{\pm}503.8mg/kg$. The total free amino acid content was 704.41 mg/100 g, the amount of methionine, citrulline and sarcosine being higher than the others. The water and 50% ethanol extracts from the dried bracken were evaluated for the total poly phenolic compound content, antioxidant activity and xanthine oxidase and ${\alpha}$-glucosidase inhibitory activity. The total polyphenol content in the 50% ethanol extract ($1574.86{\pm}18.31mg/100g$) was higher than in the water extract ($1240.24{\pm}16.32mg/100g$). The DPPH and ABT radical scavenging activity was increased according to the concentration of bracken extract, and the activity in the 50% ethanol extract was higher than in the water extract. In addition, the xanthine oxidase and ${\alpha}$-glucosidase inhibitory activity was also higher in the 50% ethanol extract than in the water extract. In conclusion, bracken has great antioxidative and antidiabetic effects and can be used as a preventive agent for oxidation and diabetes.