• The Korean Journal of Mycology
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• v.20 no.3
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• pp.259-268
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• 1992

Fifty-three actinomycetes antagonistic to Phytophthora capsici and Magnaporthe grisea were isolated from rhizosphere soils in six pepper-growing areas and ashore soils. Thirty-two antagonistic actinomycetes, showing inhibition zone larger than 5 mm, were classified into 20 groups according to their colony morphology and color. The antagonistic activity against P. capsici greatly varied, which showed inhibition zone sizes in the ranges from 5.7 to 17.5 mm on V-8 juice agar and from 2.5 to 17 mm on tryptic soy agar. The antagonistic activity of some actinomycetes tested was remarkably different between the two test media. The antagonists showed a relatively broad antifungal spectrum, but their antibacterial activity was negligible, except for Pseudomonas solanacearum. Butanol extracts of culture filtrates from antagonistic actinomycetes inhibited mycelial growth of P. capsici and M. grisea, thereby confirming strongly antibiotic production in culture. Culture filtrates of some antagonistic actinomycetes completely inhibited Phytophthora blight in pepper plants.

• The Korean Journal of Mycology
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• v.24 no.1 s.76
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• pp.17-24
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• 1996

For screening of biological activities of culture broth of some wood rotting basidiomycetes, antimicrobial activity, plant growth regulating activity, antitumor activity, and various enzyme activities were checked. Coriolus versicolor 5129 and C. pubescens 5131 strains showed inhibition activity against gram-positive bacteria and Lenzites betulina 8029 strain showed the activity against gram-negative bacteria. L. betulina 8085 inhibited the growth of both bacteria and plant pathogenic fungi. All of tested basidiomycetes inhibited the germination and growth of radish and cabbage at concentration of 0.8ml/ml. Especially, Fomitopsis pinicolor 8059 and Fomitella fraxinea 8084 showed strong inhibition activity. In contrast, Bjerkandera adusta 8054 stimulated the growth of cabbage and radish at concentration of 0.4 and 0.2ml/ml. All polysaccharides from tested basidiomycetes showed anti-tumor activity against sarcoma 180 and the stronger antitumor activity was observed in L. betulina 8029 and unidentified 8058 strain. All tested basidiomycetes had also an ability to degrade cellulose and lignin.

• Journal of Marine Bioscience and Biotechnology
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• v.14 no.1
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• pp.9-24
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• 2022

Low-molecular weight peptides derived from fish collagen exhibit several bioactivities, including antioxidant, antiwrinkle, antimicrobial, antidiabetic, and antihypertension effects. These peptides are also involved in triglyceride suppression and memory improvement. This study aimed to investigate the optimal processing condition for preparing low-molecular weight peptides from flounder skin, and the properties of the hydrolysate. The optimal processing conditions for peptic hydrolysis were as follows: a ratio of pepsin to dried skin powder of 2% (w/w), pH of 2.0, and a temperature of 50℃. Peptic hydrolysate contains several low-molecular weight peptides below 300 Da. Gly-Pro-Hyp(GPHyp) peptide, a process control index, was detected only in peptic hydrolysate on matrix-assisted laser desorption/ionization-time-of-flight(MALDI-TOF) spectrum. 2,2'-azinobis-(3-3-ethylbenzothiazolline-6- sulfonic acid(ABTS) radical scavenging activity of the peptic hydrolysate was comparable to that of 1 mM ascorbic acid, which was used as a positive control at pH 5.5, whereas collagenase inhibition was five times higher with the peptic hydrolysate than with 1 mM ascorbic acid at pH 7.5. However, the tyrosinase inhibition ability of the peptic hydrolysate was lower than that of arbutin, which was used as a positive control. The antibacterial effect of the peptic hydrolysate against Propionibacterium acne was not observed. These results suggest that the peptic hydrolysate derived from a flounder skin is a promising antiwrinkle agent that can be used in various food and cosmetic products to prevent wrinkles caused by ultraviolet radiations.

• The Korean Journal of Mycology
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• v.17 no.3
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• pp.161-168
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• 1989

Mitochondria in L. edodes were separated and purified by stepped sucrose density gradient centrifugation. In our previous work, we have found that the activation wavelengths of the mitochondrial ATPase and ATP synthase were 680 nm and 470 nm within the range of 400-700 nm, respectively. The activities of the above enzymes with wavelengths of 300-400 nm region were investigated. The mitochondrial ATPase and ATP synthase were stimulated at 380 nm and 330 nm, respectively, for 30 min illumination compared with dark control group. They, however, were inhibited at 330 nm and 350 nm, respectively. The presence of FAD resulted in inhibition of the activity of the ATPase and stimulation of the activity of the ATP synthase by the activation and inhibition wavelengths. However, the activities of these enzymes were not changed by NADH for the above wavelengths. In the spectral properties, the oxidation of $FADH_2$ into FAD occurs in the presence of the enzymes for illumination of the activation and inhibition wavelengths. Therefore, we can predict that the mitochondrial ATPase and ATP synthase may function as oxidant in the redox reaction by the light illumination and that the light-induced pigment of the mitochondrial ATP synthase should be an oxidized form of a flavoprotein.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.64-69
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• 2010

It has been known that propolis possesses anti-infective, anti-inflammatory, and anti-oxidative properties. Although antifungal activity of Propolis has already been demonstrated, very few studies has been conducted for action mechanism and its spectrum on fungi. We found that ethanol extract of propolis (EEP) inhibited in vitro translation. Since we also observed the growth inhibition of pathogenic fungi and anti-oxidative properties preliminarily, we try to see where those properties come from. Therefore we extracted the EEP further with chloroform, ethyl acetate and butanol. When their fractions were examined for the growth inhibition of Candida albicans, Saccharomyces cerevisiae, Candida glabrata, Candida lusitaniae, Cryptococcos neoformans, chloroform fraction exhibited the highest anti-fungal as well as anti-oxidative properties. Similarly the chloroform fraction showed highest translation-inhibiting activities among the various Propolis fractions. These data indicate that those properties might come from similar compounds.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.423-428
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• 2000

Bacteriocins are classified as proteins which are produced by heterogeneous groups of bacteria, having and antimicrobial effect of the closely related organisms. Recently, bacteriocins derived from lactic acid bacteria and other food-related organisms have been the subject of much research on potential food biopreservatives. The goal of this study was to screen and characterize the bacteriocinogenic lactic acid bacteria from Jeot-gal(commercial fermented fish foods). All bacteriocinogenic isolates were identified as lactic acid bacteria. Isolates NK24, NK34, and SA72 were tentatively identified as Lactobacillus brevis, according to the API 50 CHL kit database. All antimicrobial substances produced from four lactic acid bacteria isolates completely lost their antibacterial activity after being treated with some proteases, indicating to their proteinaceous nature. The bacteriocin produced from isolates NK24, NK34, and SA72 showed a broad spectrum of activity when compared to those produced from isolate SA131. All bacteriocins isolated during the course of this study showed a bactericidal mode of inhibition.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.255-255
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• 1996

Flavonoids are the large class of plant-derived polyphenolic compounds with a broad spectrum of biological actions including anti-inflammatory, anti-allergic and anti-asthmatic activities. It has been reported that quercetin and some other flavonoids inhibit the histamine release from mast cells. Disodium cromoglycate, a kind of biflavonoid, have been used as a anti-asthmatic agent. Therefore, the following study was undertaken to characterize tile structure-activity relationships of flavonoids in the inhibition of histamine release, from IgE-sensitized mast cells. Flavonoid acetate were synthesized by addition of acetic anhydride to the flavonoids dissolved in pyridine. According In the Mota method, IgE-rich serum was made in rats sensitized with Pertussis vaccine and ovalbumin. Rat abdominal mast cells were harvested and purified over tile discontineous Percoll gradients, Mast cells were preincubated in RPMI with IgE-rich serum and further incubated with flavonoids. Histamine contents released from mast cells were determined fluorospectrophotometrically after stimulation with ovalbumin. (omitted)

• Microbiology and Biotechnology Letters
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• v.32 no.3
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• pp.238-242
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• 2004

Antifungal agents, flavofungin and fungichromin were isolated from the fermentation culture broth of a Streptomyces sp. SKM338. Biological evaluation of these antibiotics indicated that the compounds possesses broad spectrum antifungal activity against various pathogens. Especially, these compounds inhibited throughly growth of Didymella bryoniae, caused Gummy stem blight of melons, occurs in the southeastern Korea. Inhibition of this pathogen may be prevented from directly reducing both pre- and post-harvest yields.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.302-307
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• 1995

Four strains of lactic acid bacteria which produced bacteriocins inhibitory to Listeria species were isolated from Kimchi, and were identified as Leuconostoc mesenteroides subsp. mesenteroides (2 strains), Leuconostoc paramesenteroides and Pediococcus pentosaceus. The bacteriocins produced by the isolates inhibited all of the Listeria monocytogenes strains tested, but L. denigrificans 28 and L. welchimeri 89 were not inhibited by the bacteriocin produced by the Leu. paramesenteroides isolate. The bacteriocin produced by the P. pentosaceus isolate was more inhibitory against sensitive strains and showed broader spectrum of antimicrobial activity than those produced by other isolates. The bacteriocins produced by Leuconostoc isolates were sensitive to pronase E treatment, but that produced by the P. pentosaceus isolate was not completely inactivated. The bacteriocins produced by all of the isolates were not sensitive to catalase, ${\alpha}$-amylase and lysozyme and heat (30 min at $100^{\circ}C$) treatments.

• Microbiology and Biotechnology Letters
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• v.19 no.1
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• pp.8-13
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• 1991

Bacteriocin-producing microorganisms were screened from raw milk and tested their antimicrobial activities against Lactobacillus plantarum ATCC 8014 as target organism, Antimicrobial substances isolated showed broad antimicrobial spectra against Gram positives and negatives. Strain 1112-1 was selected as a test organism due to its highest antimicrobial activity among the isolates. Antimicrobial substance produced by 1112-1 completely suppressed the growth of Lactobacillus plantarum at 230 IUIml and showed 11% growth inhibition of E. coli at 500 IUIrnl level. The antimicrobial substance was found to be proteinaceous material which was inactivated by carboxypeptidase, elastase, alpha amylase, amyloglucosidase, pronase, protease IV, alpha chymotrypsin, ficin, cellulase, phosphatase and lipase. The molecular weight was estimated by SDS-PAGE as 5,900. The isolate 1112-1 was identified as one of the related strains of Lactococcus sp. The strain was different from Lactococcus lactis in the following characteristics: late positive in maltose and sucrose fermentation; positive in mannitol and salicin fermentation; negative in lactose fermentation.