• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.379-386
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• 2011

The objective of this work was to investigate the ability of the plant growth-promoting rhizobacterium Pseudomonas aureofaciens 63-28 to induce plant defense systems, including defense-related enzyme levels and expression of defense-related isoenzymes, and isoflavone production, leading to improved resistance to the phytopathogen Rhizoctonia solani AG-4 in soybean seedlings. Seven-day-old soybean seedlings were inoculated with P. aureofaciens 63-28, R. solani AG-4, or P. aureofaciens 63-28 plus R. solani AG-4 (P+R), or not inoculated (control). After 7 days of incubation, roots treated with R. solani AG-4 had obvious damping-off symptoms, but P+R-treated soybean plants had less disease development, indicating suppression of R. solani AG-4 in soybean seedlings. Superoxide dismutase (SOD) and catalase (CAT) activities of R. solani AG-4-treated roots increased by 24.6% and 54.0%, respectively, compared with control roots. Ascorbate peroxidase (APX) and phenylalanine ammonia lyase (PAL) activities of R. solani AG-4-treated roots were increased by 75.1% and 23.6%, respectively. Polyphenol oxidase (PPO) activity in soybean roots challenged with P. aureofaciens 63-28 and P+R increased by 25.0% and 11.6%, respectively. Mn-SOD (S1 band on gel) and Fe-SOD (S2) were strongly induced in P+R-treated roots, whereas one CAT (C1) and one APX (A3) were strongly induced in R. solani AG-4- treated roots. The total isoflavone concentration in P+Rtreated shoots was 27.2% greater than the control treatment. The isoflavone yield of R. solani AG-4-treated shoots was 60.9% less than the control.

• Food Science and Preservation
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• v.10 no.1
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• pp.11-15
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• 2003

Various quality characteristics of minimally processed mushroom were measured to select appropriate browning inhibitor. The treatment of extracts from Asparagi radix, cassia and kiwi on mushrooms have a high effectiveness like ascorbic acid or cysteine, known as a good chemical antibrowning agent. As a results of physical quality characteristics of minimally processed mushroom during storage, 1% cysteine and Asparagi radix were highly effective on degree of browning. Total phenol content and polyphenol oxidase activity showed slight differences among the mushroom treated with each browning inhibitors, but it has gradually increased during storage. Thus, these results suggest browning inhibitors from natural materials can be alternatives to prevent browning on mushrooms instead of chemical browning inhibitors including ascorbic acid or cysteine, has been widely used for antibrowning agent.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.188-194
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• 2009

In this study, we evaluated the phytochemical compositions of the fruits of the pear cactus, mulberry, and Korean black raspberry to determine how they related to antioxidant capacity. Specifically, the total soluble polyphenol, flavonoid and anthocyanin contents were determined, and the phenolic compounds were evaluated by HPLC. In addition, the antioxidant capacity was evaluated by electron paramagnetic resonance (EPR), SOD-like activity and nitrate scavenging activity. Korean black raspberry was found to have the highest level of phytochemicals, followed by mulberry and pear cactus (p<0.05). Furthermore, EPR revealed that Korean black raspberry extract (100 ${\mu}g$/mL) removed 78.6% of the superoxide radicals in a xanthin-xanthin oxidase. Additionally, when the removal of hydroxyl radicals was evaluated, the extract of pear cactus showed 50% scavenging activity at 1000 ${\mu}g$/mL. Korean black raspberry extract showed the highest SOD-like activity, which was 44% (p<0.05). Finally, the nitrate scavenging activity of both extracts of mulberry and Korean black raspberry were found to be 93%, while that of the pear cactus was 63% at pH 1.2 (p<0.05).

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.793-799
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• 2007

The purpose of this research related to the development of natural preservatives, in which licorice and spices (clove, fennel fruit and Chungyang green pepper) were extracted with distilled water, and the extracts were tested for their antibacterial and antioxidative activities. The polyphenol contents of the water extracts from licorice, clove, fennel fruit and Chungyang green pepper were 17.4, 21.4, 6.6, and 0.9 mg/g, respectively. The water extracts from licorice and clove demonstrated antibacterial activity against S. aureus. The electron donating abilities (EDA) of the water extracts from the licorice and other spices ranged from 60 to 88% at 1,000 ppm; the highest value was for the licorice followed by fennel fruit, clove, and green pepper. The xanthine oxidase inhibition ratio (XOD) of the extracts ranged from 28 to 50% at 1,000 ppm, where the highest value occured in the cloves, followed by fennel fruit, green pepper, and licorice. The superoxide dismutase (SOD)-like activity ranged from 33 to 53% at 1,000 ppm, and the highest value was for the licorice followed by cloves, fennel fruit, and green pepper. The nitrite scavenging abilities (NSA) at 1,000 ppm of the clove and fennel fruit water extracts were 95% and 65% at pH 1.2, respectively. The NSAs of the extracts were highest at pH 1.2, and decreased with increasing pH. Considering all the obtained results, we have concluded that licorice and spice extracts can be used as natural preservatives in the development of health foods.

• The Journal of Korean Medicine
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• v.30 no.5
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• pp.26-41
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• 2009

Objectives: The experiment was to estimate the value of Saengmaegsan as a therapeutic anti-aging agent with an analysis of ingredients and their bio-activating effects by enzymologic methods. Methods: We analyzed anti-aging effects of the ingredients of Saengmaegsan being Liriope Platyphylla, Schizandrae Chinensis, and Schizandrae Chinensis. Results: In Liriope Platyphylla and Schizandrae Chinensis, reducing sugar concentration was shown at the highest level. Of mineral contents, K+ and Na+ were the highest in Saengmaegsan and each ingredient also, and then Ca++ and Al. The amount of polyphenol showed was in order Schizandrae Chinensis > Saengmaegsan > Panax Ginseng > Liriope Platyphylla. The electron donating ability of Schizandrae Chinensis doubled that of Saengmaegsan and Panax Ginseng, at the same time that one per 1 ml in Saengmaegsan was significantly found the greatest level as compared to each single ingredient. SOD-like activity was high in Saengmaegsan and Schizandrae Chinensis. SOD-like activity of Saengmaegsan was higher than in single components. Nitric oxide inhibition in pH 1.2 was high in Saengmaegsan and Schizandrae Chinensis, and for per 1 ml it showed the same pattern as above. In pH 3.0 the result was not different from in pH 1.2. Xanthine oxidase inhibition was high in Schizandrae Chinensis and for per 1 ml showed the greatest activity in Liriope Platyphylla. Tyrosinase inhibition in Omija was the most noticeable, and for per 1 ml was Liriope Platyphylla more than any others. Conclusions: With this analysis of ingredients, it is proven that Saengmaegsan and each component fosters antioxidation. On the whole, the composite prescription Saengmaegsan was superior to each individual component.

• The Plant Pathology Journal
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• v.36 no.2
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• pp.133-147
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• 2020

Hexanal, a C-6 aldehyde has been implicated to have antimicrobial properties. Hence, this study was conducted to determine the antifungal activities of hexanal vapor against major postharvest pathogens of banana viz., Colletotrichum gloeosporioides and Lasiodiplodia theobromae. The pathogens were cultured in vitro and exposed to hexanal vapor at 600, 800, 1,000 and 1,200 ppm. Mycelial growth of both fungal pathogens were inhibited completely at 800 ppm and the incidence of anthracnose and stem-end rot diseases reduced by 75.2% and 80.2%, respectively. The activities of peroxidase, polyphenol oxidase, phenylalanine ammonia-lyase and glucanase had transiently increased in hexanal vapor treated banana by 5 to 7 days and declined thereafter. Postharvest treatment of banana with hexanal vapor resulted in phospholipase D inhibition and also resulted in cell wall thickening of the treated fruit, which impeded the penetration of the pathogenic spores. This was further confirmed by scanning electron micrographs. The defense-related protein intermediaries had increased in hexanal vapor treated banana fruit, which suggests induced resistance against C. gloeosporioides and L. theobromae, via., the phenylpropanoid pathway which plays a significant role in hindering the pathogen quiescence. Delayed ripening due to inhibition of phospholipase D enzyme, inhibition of mycelial growth and induced systemic resistance by defense enzymes collectively contributed to the postharvest disease reduction and extended shelf life of fruit.

• Korean journal of food and cookery science
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• v.28 no.3
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• pp.319-326
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• 2012

This study was designed to investigate the properties related to browning of hot water and 80% ethanol extracts of green tea (Camellia sinensis) and propolis. The extracts were assessed for polyphenol oxidase (PPO) inhibitory activity and total phenolic and flavonoid contents. In addition, apples were cut into 15 mm thick slices and dipped for 1 min in 0.5% of the green tea extracts and the propolis solutions and stored at room temperature for 24 h. The PPO inhibitory activity of the green tea extracts was better than that of the propolis. The highest DPPH free radical scavenging activity (90.81%), total phenol contents (170.42 mg/mL) and the metal chelating effects (45.93%) were measured in the green tea hot water extracts. The mineral content of the green tea water extracts was 69,328.44 ppm potassium and 2,409.42 ppm magnesium. After 24 h, the ${\Delta}E$ value of the apple slices treated with the green tea water extracts was the lowest (1.35). The antibrowning effects of the green tea extracts were higher than those of propolis in the apple slices.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.407-415
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• 2012

An endophytic bacterium, Bacillus thuringiensis GS1, was isolated from bracken (Pteridium aquilinum) and found to have maximal production of chitinase (4.3 units/ml) at 5 days after culture. This study investigated the ability of B. thuringiensis GS1 to induce resistance to Rhizoctonia solani KACC 40111 (RS) in cucumber plants. Chitinase activity was greatest in RS-treated plants at 4 days. ${\beta}$-1,3-Glucanase activity was highest in GS1-treated plants at 5 days. Guaiacol peroxidase (GPOD) activity increased continuously in all treated plants for 5 days. Ascorbate peroxidase (APX) activity in RS-treated plants was increased 1.5-fold compared with the control at 4 days. Polyphenol oxidase (PPO) activity in RS-treated plants was increased 1.5-fold compared with the control at 3 days. At 5 days after treatment, activity staining revealed three bands with chitinase activity (Ch1, Ch2, and Ch3) on SDS-PAGE of cucumber plants treated with GS1+RS, whereas only one band was observed for RS-treated plants (Ch2). One GPOD isozyme (Gp1) was also observed in response to treatment with RS and GS1+RS at 4 days. One APX band (Ap2) was present on the native-PAGE gel of the control, and GS1- and GS1+RS-treated plants at 1 day. PPO bands (Po1 and Po2) from RS- and GS1+RS-treated plants were stronger than in the control and GS1-treated plants upon native-PAGE at 5 days. Taken together, these results indicate that the induction of PR proteins and defense-related enzymes by B. thuringiensis GS1 might have suppressed the damping-off caused by R. solani KACC 40111 in cucumber plants.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.225-231
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• 2014

In this study about the optimum conditions for the production of laccase, a polyphenol oxidase involved in lignin degradation, from Marasmius scorodonius, a white-rot fungus garlic mushroom, were determined. Amongst the tested media used for the enzyme's production, YM medium (1% dextrose, 0.5% malt extract, 0.3% yeast extract) allowed for the highest activity of the enzyme. Then, to optimize the culture conditions for laccase activity, the influence of various carbon and nitrogen sources was investigated in YM medium. Among various carbon and nitrogen sources, 1% galactose and 0.4% yeast extract resulted in the highest production of the enzyme, respectively. Enzyme production attained its highest level after cultivation for 15 days at $25^{\circ}C$. Zymogram analysis of the culture supernatant showed two isoenzymatic bands with molecular masses of 60-70 kDa. The optimum pH and temperature for enzyme activity were 3.4 and $75^{\circ}C$, respectively.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.232-235
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• 1997

This study was investigated to determine antimutagenic effects of enzymatic browning reaction products (PEBRPs) obtained by reaction of polyphenol compouns with oxidase extracted from potato. Catechol (Ca) PEBRPs showed the strongeest inhibitor effects with 90% inhibition on benzo-($\alpha$)-pyrene(B($\alpha$)P) induced mutagenesis in Salmonella typhimurium TA98, but he least with40% inhibition on the 2-aminofluorene (2-AF) induced mutagenesis in TA98. The strong antimutagenic activities with 80% inhibition were observed in the presence of 100$\mu\textrm{g}$/plate of hydroquinone(HQ)-PEBRP on the B($\alpha$)P or 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole(Trp-P-1) induced mutagenesis in TA98, whereas HQ-PEBRP showed the least antimutagenic effect on 2-AF-induced mutagenesis. The addition of 100$\mu\textrm{g}$ hydroxyhydroquinone(HHQ)-PEBRP to the plate led to approximately 82% inhibitory effects on 2-AF or Trp-P-1 induced mutagenesis in TA98, whereas the least antimutagenicity was obsrved in the4-nitroquinoline-1-oxide(4-NQO) induced mutagenesis in the presence of 100$\mu\textrm{g}$/plate of HHQ-PEBRP. More than 80% inhibiton were observed in the presence of 200$\mu\textrm{g}$/plate of Pyrogalol(Py)-PEBRP on the B($\alpha$)P or Trp-P-1 induced mutagenesis in TA98, but the least with 38% inhibition on 4-NQO induced mutagenesis in TA98. The results indicate that enzymatic browing reaction products of potato have a strong modulatory effect on mutagen induced mutagenesis in TA98.