• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.706-713
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• 2012

This study was carried out to investigate the contents of monacolin K and citrinin, along with the sensory quality and antioxidant activity of mulberry leaf tea fermented by $Monascus$ $pilsous$ (FMM). Total monacolin K content of FMM was 0.058%, but citrinin was not detected. Redness of brewed FMM was remarkably higher than that of unfermented mulberry leaf tea (UFM). In sensory evaluation of brewed FMM, while astringent taste and savory taste were lower, flavor, color, and overall acceptability were significantly higher than those of UFM. Total polyphenol contents of UFM and FMM were 83.1 and 23.61 mg/g (dry basis), total flavonoid contents of UFM and FMM were 17.96 and 3.99 mg/g (dry basis), respectively. Xanthine oxidase (XO) inhibitory activity and superoxide dismutase (SOD)-like activity of FMM were lower than those of UFM. Electron-donating ability and ferric-reducing antioxidant power of FMM were slightly lower than those of UFM. However, the antioxidant activities of FMM per polyphenol content were markedly higher than those of UFM. These results suggest that FMM may scavenge excessive reactive oxygen spices (ROS) via inhibition of XO and SOD-like activity. Furthermore, FMM demonstrated relatively higher acceptability and antioxidant ability along with functionality of $Hongguk$ (red yeast rice), and therefore could be utilized to prevent various ROS-induced diseases.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.479-486
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• 2008

The cultural characteristics and antibacterial activities of Cordyceps militaris and Paecilomyces tenuipes were compared. The mycelial growth was the highest on MCM (Mushroom Complete Medium) for C. militaris and on YMA (Yeast Malt Agar) for P. tenuipes. But the mycelial density on MMM (Mushroom Minimal Medium) was lower than other on media. The optimum mycelial growth was observed at $25^{\circ}C$. C. militaris was low mycelial growth when it was transferred over 5 times generation. The carbon source for the optimum mycelial growth was fructose of monosaccharide, maltose of disaccharide and dextrin of polysaccharide. The calcium nitrate of organonitrogen was found the best mycelial growth on C. militaris, while the sodium nitrate observed to be well for mycelial growth on P. tenuipes. The ammonium tartrate was observed to be the best among the inorganonitrogen used for mycelial growth. Antibacterial activities were found out just C. militaris against Bacillus cereus of Gram (+).

• Korean Journal of Poultry Science
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• v.37 no.3
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• pp.215-219
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• 2010

The applicability of electronic nose was tested to detect lipid peroxidation in chickens and to measure antioxidant effect of astaxanthin in chicken carcasses. Two sources of astaxanthin were fed to 62-wk-old spent laying hens to improve meat quality: natural astaxanthin (NA) from the red yeast, Phaffia rhodozyma, and synthetic astaxanthin (SA) from chemical synthesis. One hundred forty four ISA Brown laying hens were used in a 6-wk feeding trial. Three treatments consisted of the basal diet (control), SA (100 mg astaxanthin/kg basal diet) and NA (50 mg astaxanthin/kg basal diet). The astaxanthin levels of SA and NA were set to give a similar degree of skin pigmentation. After 6-wk feeding of astaxanthin, the skins from NA and SA were discriminated from the control by electronic nose. However, electronic nose failed to distinguish between SA and NA skins after 6-wk feeding. The astaxanthin level differences between skins of SA and NA were not remarkable during the 6-wk trial. The lipid peroxide formation in skin was significantly decreased by SA but not by NA. The antioxidation effect of SA was detected by electronic nose because SA skin was discriminated from others. NA was a better pigmentation agent than SA, but the reverse was true in antioxidation. Electronic nose is applicable for detecting astaxanthin in chicken, and meat off-flavor caused by lipid peroxidation during storage.

• Journal of Plant Biotechnology
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• v.2 no.2
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• pp.79-82
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• 2000

We have isolated a cDNA encoding a calcium-dependent protein kinase (CDPK) in Nicotiana tabacum, which was designated NtCDPK1. Accumulation of the NtCDPK1 mRNA was stimulated by various stimuli, including phytohormones, CaCl$_2$ wounding, fungal elicitors, chitin and methyl jasmonate. The NtCDPK1 gene encodes a functional Ser/Thr protein kinase of which phosphorylation activity is strongly induced by calcium. By analyzing expression of the NtCDPK1-GFP fusion protein and by immunoblotting with antibody which reacts with NtCDPK1, we found that NtCDPK1 is localized in membrane and nucleus in plant cells. Silencing expression of the NtCDPK1 transgene resulted in marked decrease of lateral root development in the transgenic tobacco plants. Yeast two hybrid screening using NtCDPK1 as a bait identified a tobacco homologue of proteasome regulatory subunit 21D7, designated Nt21D7. The 21D7 mRNA has been shown to be predominantly expressed in proliferating tissues in the cell cycledependent manner in carrot. The recombinant NtCDPK1 protein associated with Nt21D7 in vitro, and could phosphorylate the Nt21D7 protein in vitro in the presence of calcium, suggesting that Nt21D7 protein is a natural substrate of NtCDPK1 in tobacco. These results suggest that NtCDPK1 may regulate tell proliferation processes, such as lateral root formation, by regulating specificity and/or activity of proteasome-mediated protein degradation pathway.

• Journal of Life Science
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• v.8 no.6
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• pp.648-653
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• 1998

The development of natural food preservatives instead of chemical synthetic food preservatives is world wide inte-rest. Authors already investigated that cinnamon bark extract revealed antimicrobial activity against general spoilage microorganisms of food especially its acitivity was stronger against molds than against bacteria. In this paper, authors examined the mirobial flora from the spoiled fish meat paste products and also checked the possibility of cinnamon bark extract food preservative for prolong the shelf life of the fish paste product and breads. The predominat bacteria was Bacillus sp. as about 98% of the total microorganisms isolated from unpacked or packed spoiled fish meat paste products. While molds and yeast are not detected from the vacuum packed products. The MIC(minimum inhibitory concentration) of cinnamon bark extract against the isolated spoilage bacteria and molds was 160~640$\mu\textrm{g}$/$m\ell$ and 40~80$\mu\textrm{g}$/$m\ell$, respectively. When the diluted cinnamon bark extract (the extract : ethanol=1 : 3) was sprayed on the surface of fried fish meat paste product, molds growth was delayed by 2 days at room temperature. The shelf lifes of sandwich and glutinousrice bread which surface sprayed with the diluted extract(1 : 1) was extended by 5 and 7 days, respectively.

• Microbiology and Biotechnology Letters
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• v.47 no.4
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• pp.565-573
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• 2019

Production of biofuels and value-added materials from cellulosic biomass requires the development of a microbial strain capable of efficiently fermenting mixed sugars. In this study, the natural xylose fermenting yeast, Pichia stipitis, was evolved to simultaneously ferment cellobiose and xylose. Serial subcultures of wild-type P. stipitis in 20 g/l cellobiose were performed to increase the rate of cellobiose consumption. A total of ten rounds of the serial subculture led to the isolation of an evolved strain fermenting cellobiose significantly faster than the parental strain. The evolved strain displayed enhanced ethanol yield from 0 to 0.4 g ethanol/g cellobiose. The evolved P. stipitis simultaneously fermented cellobiose and xylose in batch fermentation. The genetic information of our evolved P. stipitis would be valuable in the development of a microbial host for the production of biofuels and biomaterials from cellulosic biomass.

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.473-478
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• 1986

In order to elucidate the patterns of natural oils and fats assimilation by microorganisms, lipases properties of yeast and bacterium strain, Torulopsis candia Y-128 and Acinetobacter calcoaceticus KB-2, which could assimilate palm oil efficiently, were investigated. T candida Y-128 attached palm oil droplets directly, and assimilated unsaturated fatty acid more easily than saturated acids liberated by the action of its lipase. Lipase of A. calcoaceticus KB-2 was extracellular and appeared quickly from the beginning of log phase of growth, whereas lipase of f candida Y-128 appealed intracellular. The lipases of two strains seem to be only enough to utilize the lipid materials for their own growth, without accumulation of lipases in the culture broth. Lipases of the strains have 1 (3-)-positional specificities on triglycerides. The patterns of palm oil assimilation showed that two strains attached droplets of lipid materials directly and split off fatty acids at 1 (3-)-position of triglycerides first, and assimilated the reaction products via fatty acids metabolic pathway.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.368-372
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• 2006

Quercetin is a flavonoid molecule that is known to tie in various sources of natural products such as vegetables and fruits. It has been proven that quercetin plays a crucial role in the prevention of colon cancer as well as homeostasis as radical scavenger in human body. It is also well-known that glycosidases, including $\alpha$-glucosidase, are involved in a variety of degenerative metabolic disorders. In the course of screening useful $\alpha$-glucosidase inhibitors, we screened out quercetin as a $\alpha$-glucosidase inhibitor from chemical libraries. Quercetin was shown to be a reversible, slow-binding, and noncompetitive inhibitor of yeast a-glucosidase with a K$_i$ value of $6.3\times10^{-8}$ M when it was included with an enzyme mixture. Together, these results show that quercetin has potential in treating disorders including diabetes, although the further mechanistic study is needed.

• Food Science and Preservation
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• v.10 no.1
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• pp.89-93
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• 2003

To develope natural food preservatives, ethanol and water extracts were prepared from the Lentinus edodes and antimicrobial activities were examined against 10 microorganisms which were food borne pathogens and / or food poisoning microorganisms and food-related bacteria and yeasts. Ethanol extract exhibited antimicrobial activities for the microorganisms tested, but not on lactic acid bacteria and yeast Especially, minimum inhibitory concentration(MIC) for Escherichia coli were as low as 0.5 mg/mL. Antimicrobial activity of the ethanol extract was stable by the heating at 121$^{\circ}C$ for 15 min and not affected by pH. The ethanol extract of Lentinus edodes exhibiting high antimicrobial activity. The highest antimicrobial activity adjust bacteria tested was found in the ethylacetate fraction.

• The Plant Pathology Journal
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• v.15 no.3
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• pp.152-157
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• 1999

An antibiotic compound was isolated from the culture of an antagonist against Fusarium oxysporum f. sp. sesami, Bacillus polymyxa strain KB-8, and tested for the control of Fusarium wilt of sesame in greenhouse conditions. Optimum conditions for culturing the antagonist to obtain the maximum antibiotic activity were determined using different culture media, initial medium acidity, and incubation periods for which yeast -malt extract agar with the initial acidity of pH 5 and over 13 days culture were best. Antibiotic substances extracted by methanol had 2 main fractions, KB-8A and KB-8B, in thin layer chromatography (OLC) with Rf values of 0.35 and 0.67 in a solvent system of chloroform : methanol = 7 : 3. The fraction KB-8A wa purified further by XAD-2, silica gel and Sephadex LH-20 column chromatography, and crystalization. Its minimum inhibitory concentrations (MICs) were $12.8\mu\textrm{g}$/ml for F. oxysporum and Alternaria mali, $6.4\mu\textrm{g}$/ml for Colletotrichum gloeosporioides and Rhizoctonia solani, and $3.2\mu\textrm{g}$/ml for Phytophthora capsici. Soil drenching of antibiotic KB-8A in the concentrations of $13.0\mu\textrm{g}$/ml and $26.0\mu\textrm{g}$/ml effectively inhibited the Fusarium wilt of sesame in a greenhouse test, which appeared to be comparable to the fungicide benlate of $6.5\mu\textrm{g}$ a. i./ml.