• Korean Journal of Microbiology
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• v.51 no.4
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• pp.448-452
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• 2015

The bacterial strain that was isolated from chinese cabbage rhizosphere, showed inhibition of yeast growth. This strain was identified as Pseudomonas fluorescens BB2 by API 20NE test and 16S rRNA gene sequence analysis. P. fluorescens BB2 strain produced antibiotics against yeast as a secondary metabolite effectively when the culture was carried out in YM medium with 3% glucose at $20^{\circ}C$. The protein antibiotic of BB2 strain which was concentrated by ammonium sulfate precipitation and n-butanol extraction inhibited the growth of yeast with the minimal inhibitory concentration of $10{\mu}g/ml$ against Candida albicans KCTC 7965, and the growth of yeast was completely inhibited at $80{\mu}g/ml$. The hydrophilic fraction of n-butanol extraction inhibited the growth of Bacillus cereus ATCC 21366, showed orange halo on chrome azurol S plate, which means the fraction contained iron chelating siderophore. The results of crystal violet uptake through the cell membrane showed that membrane permeability was increased about 9% than control, when the concentration of hydrophobic antibiotic against yeast C. albicans was $60{\mu}g/ml$. As a result, the antibiotic produced by P. fluorescens BB2 against yeast Candida is considered antimicrobial peptide, and this is the first report in the genus Pseudomonas.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.219-224
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• 1998

The cyclic metabolism of poly(3-hydroxyhutyrate-co-3-hydroxyvalerate) synthesized from glucose by Alcaligenes sp. SH-69 in the presence or absence of new carbon substrate was investigated. In batch culture, the content and weight average molecular weight of the copolymer already stored in the cell decreased rapidly when there was no other carbon source available. After the depletion of carbon source, the amount of high molecular weight copolymer decreased more rapidly than that of low molecular weight copolymer, and as a result, average molecular weight distribution shifted to the lower value. The addition of a mixture of glucose and levulinic acid when the initial carbon substrate, glucose, was nearly depleted supported the continual increase in cell mass and the accumulation of poly(3HB-co-3HV) with high molar fraction of 3HV. However, solvent fractionation of the polymer with acetone revealed the degradation of pre-existing polyhydroxyalkanoale (PHA) in parallel with the synthesis of PHA from new carbon substrate. Even though PHAs obtained from each substrate alone were the copolymer of 3HB and 3HV, it was found that the polymer accumulated in the cells grown by sequential feeding was mainly physical mixture of two poly(3HB-co-3HV) copolymers containing different molar fractions of 3HV.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.393-400
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• 2022

Postharvest quality of sweet pepper fruits was mainly defined as external appearance, i.e., shape, fruit weight and surface color. These quality traits tend to involve esthetic appeal, it disregards gustatory properties and nutritional value. However, comparative studies according to the marketability of sweet pepper fruits are insufficient. This study was carried out to compare the physicochemical components, antioxidant activity and carotenoid contents of marketable and unmarketable sweet pepper fruits (Capsicum annuum L.). Physicochemical components (proximate composition, minerals and total phenolic contents) and antioxidant activities using various methods were investigated. The proximate composition values (%) of marketable and unmarketable fruits were: moisture (90.28 and 90.29), ash (0.74 and 0.26), crude protein (0.67 and 0.72), crude lipid (0.38 and 0.32). There were no significant differences in antioxidant activity, while total phenolic content was higher in marketable fruit. Carotenoids contents were 29.3 ± 2.6 and 31.9 ± 2.9 ㎍·g^-1 in marketable and unmarketable fruits respectively, and identified β-carotene, violaxanthin, neoxanthin, and zeaxanthin. Lutein and capsaicin were not detected. In this study, potential value of unmarketable sweet pepper fruit could be identified to be applied as a food ingredient and functional food material.

• Applied Microscopy
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• v.33 no.3
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• pp.233-241
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• 2003

Patterns of tannin accumulation in leaves of C-4 Euphorbia maculata have been examined using electron microscopy. Tannins, which are secondary metabolite phenolic compounds, were found to be deposited conspicuously in vacuoles of certain tissues regardless of their stage in development. However, patterns of deposit accumulation were distinguishable by their cell type during leaf differentiation. The deposits appeared most concentrated in the concentric bundle sheath cells enclosing veins, while little or no density was detected mostly in the mesophyll cells close to the epidermis. An ultrastructural study revealed that the deposits were restricted to the vacuoles at an early stage of leaf development; during which the vacuoles were almost completely filled with the tanniferous substances. The deposits themselves took different forms ranging from granules to huge globules while expanding leaf blade. As the leaf matured, the deposits accumulated either centripetally adjacent to the inner tangential tonoplast or by penetration into the cytoplasm amongst various cellular organelles, resulting in an extremely dense cytoplasm. Electron micrographs frequently showed the delineation of each organelle by the presence of dense deposits within the cytoplasm. Some large depository vacuoles filled with tannins had a corrugated appearance on the sectioned surface. The pattern and potential role of the deposits have been discussed.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.35-40
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• 1987

The antilipidperoxidative effects of Brazilin and Hematoxylin were investigated at the levels of liver~total homogenates, -microsomal fraction, -mitochondrial fraction and the sera of SD-rats intoxicated with $CCl_4$ and ethanol. Both natural dyes markedly inhibited the lipidperoxidation induced by $CCl_4$ and ethanol. Brazilin and Hematoxylin showed the inhibitory effects on the both enzymatic (NADPH-dependent) and nonenzymatic (Ascorbate-induced) lipidperoxidation pathways. but it is supposed that the antilipidperoxidative powers of them mainly result from the inhibition of the nonenzymatic lipidperoxidation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.80-85
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• 2014

This study was focused on the development of fermented mushroom water extracts with antioxidative activities. Mushroom water extracts were fermented with Bifidobacterium bifidum, Lactobacillus plantarum, Lactobacillus acidophilus, Leuconostoc lactis, Streptococcus thermophilus and Lactobacillus sakei subsp. LI033 was isolated from kimchi. Fermented mushroom water extracts increased DPPH and ABTS radical scavenging activities in a dose-dependent manner. However, radical scavenging activity of fermented Phellinus linteus and Ganoderma lucidum water extracts was decreased compared to non-fermented mushroom water extracts. Antioxidative activity of fermented mushroom water extracts was also confirmed by xanthin oxidase (XO) inhibition and superoxide dismutase (SOD) activities at the same concentration. As the fermentation progressed, fermented mushroom water extracts increased XO inhibition activity and SOD activity. In conclusion, fermented mushroom water extracts were tentatively identified to enhance enzyme activity.

• Research in Plant Disease
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• v.17 no.2
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• pp.121-128
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• 2011

Bacteriolytic myxobacteria have been known to secrete various antifungal metabolites against several soilborne phytopathogens including Phytophthora. Among the three isolates of Myxococcus spp., KYC 1126 and KYC 1136 perfectly inhibited the mycelial growth of Phytophtora capsici in vitro. In order to show the biocontrol activity on Phytophthora blight of hot pepper, we tried to find the best way of application of a myxobacterial isolate. Although KYC 1126 fruiting body was easily grown on the colony of Escherichia coli as a nutrient source, it did not control the disease when it was pre-applied in soil. Before the bioassay of a liquid culture filtrate of KYC 1126 was conducted, its antifungal activity was confirmed on the seedlings applying with the mixture of the pathogen's zoospore suspension and KYC 1126 filtrate. On greenhouse experiments with five and four replications, the control value of KYC 1126 on phyllosphere and rhizosphere was 88% and 36%, respectively. Whereas, the control value of dimetnomorph+propineb on phyllosphere was 100% and that of propamorcarb on rhizosphere was 44%. There was a phytotoxicity of the myxobacterial filtrate when seedlings were washed and soaked for 24 hours. Gummy materials were covered with roots. And stem and petiole were constricted, then a whole seedling was eventually blighted.

• KSBB Journal
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• v.16 no.4
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• pp.344-350
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• 2001

The effect of salinity stress of Brassica olearacea and Capsicum annuum were studied at various levels of salinity conditions(Na-gluconate, K-gluconate, NaCl, KCl). The effects of salinity stress were measured by seedling growth rates and secondary metabolites contents of the stressed plants. Each seedling studied on the response of different salinity stress. Seedling growth of Capsicum annuum was inhibited up to 200 mM salt tolerance and Brassica olearacea was inhibited up to 400 mM salt tolerance. The produced anthocyanin was separated to high value from 200 mM NaCl in case of Brassica olearana and 50 mM K-gluconate in case of Capsicum annuum. The BADH activity was very high in Brassica olearacea seedlings treated with 200 mM NaCl and in Capsicum annuum seedlings treated with 100 mM K-gluconate. The BADH activities were increased during the early culture days, it induced betaine synthesis. The salinity stress promoted BADH activiy, subsequently endogenous betaine contents were increased, and it seemed to be secure seedling from salinity stress. The salinity concentration of 200 mM was effective on the inhibition of seed germination and on the increase of proline accumulation in tissue. The inhibition of seedling growth and accumulation of secondary metabolites in seedling were caused osmotic hypersensitivity against salinity stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.232-239
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• 1996

돌연변이 유발 물질인 mitomycin C(MMC)를 처리하여 배양한 Chinese hamster ovary(CHO) cell에 대한 감잎차 추출액의 항돌연변이 효과를 자매 염색 분체 교환(sister chromatid exchange, SCE) 시험법을 사용하여 측정하여 보았다. 감잎차 추출액 자체는 CHO 세포의 SCE 빈도수를 변화시키지 않았으며, 세포의 분열 주기중 S phase에 S9 mixture 없이 감잎차 추출액이 처리되었을 경우 MMC로 유도된 SCE 빈도수를 감소시키지 않았다. 그러나 S9 mixture 존재하에 $G_{1}$ phase에서 MMC 처리 후 감잎차를 처리하는 후처리 방식으로 감잎차 추출액을 처리하였을 때, 저농도($\leq$40$\mu\textrm{g}$/ml)에서 MMC로 인해 유발된 SCE 빈도수가 낮아지는 것을 볼 수 있었다. 이에 비해 고농도(>40$\mu\textrm{g}$/ml)에서는 SCE 빈도수의 감소 효과가 없었다. 본 연구결과, MMC 처리된 CHO 세포에 대한 감잎차 추출액의 항돌연변이 효과를 볼 수 있었고, 이 효과는 S9 mixture 존재하에서 저농도의 감잎차 추출액이 $G_{1}$ phase에 처리되었을 때 나타났다. 감잎차 추출액의 이러한 항돌연변이의 효과의 기전은 감잎차 추출액의 대사산물이 MMC 처리된 CHO 세포에 대한 DNA-excision repair activity를 촉진시키기 때문인 것으로 생각된다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2012.04a
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• pp.448-451
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• 2012

현대의 사회는 화재 등과 같은 많은 위험요소를 포함하고 있으며 이중 곰팡이와 같은 미생물에 의해 인체에 미치는 피해 또한 무시할 수 없다. 곰팡이는 우리의 주변에서 흔히 관찰 할 수 있는데 건물 실내의 벽면에서 주로 확인 할 수 있으며 곰팡이 균의 독소를 조사하여 보면 크게 세 가지로 분류 할 수 있다. 곰팡이 독소는 곰팡이 속들에 의해 생성되는 것으로서 아플라 톡신이 대표적인 예이며, 그 외에도 오크라톡신, 파튤린 등이 있고 곰팡이 독소는 곰팡이가 생산하는 2차 대사산물로 발암 물질을 포함하고 있어 인체에 큰 위험 요소라 할 수 있는데 본 연구에서는 건축물의 벽면에 발생하는 곰팡이 균을 편백수(피톤치드)를 활용한 방재 기술을 연구하고자 한다.