• Mycobiology
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• 제43권4호
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• pp.435-443
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• 2015

Sixty-one endophytic fungus strains with different colony morphologies were isolated from the leaves, stems and roots of Tephrosia purpurea with colonization rates of 66.95%, 37.50%, and 26.92%, respectively. Based on internal transcribed spacer sequence analysis, 61 isolates were classified into 16 genera belonging to 3 classes under the phylum Ascomycota. Of the 61 isolates, 6 (9.84%) exhibited antifungal activity against one or more indicator plant pathogenic fungi according to the dual culture test. Isolate TPL25 had the broadest antifungal spectrum of activity, and isolate TPL35 was active against 5 plant pathogenic fungi. Furthermore, culture filtrates of TPL25 and TPL35 exhibited greater than 80% growth inhibition against Sclerotinia sclerotiorum. We conclude that the endophytic fungal strains TPL25 and TPL35 are promising sources of bioactive compounds.

• Journal of Plant Biotechnology
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• 제49권1호
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• pp.99-105
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• 2022

This study assessed the antioxidant and anti-inflammatory activities of leaf extracts from grain amaranths (Amaranthus spp.). Among all the extracts, the ethanol extract of Amaranthus cruentus leaves (Ar) exhibited the highest antioxidant activity, including the DPPH free radical scavenging activity and ORAC. In addition, Ar strongly inhibited nitric oxide production by suppressing the MEK/ERK signaling pathway in lipopolysaccharide-stimulated RAW264 murine macrophages. HPLC analysis revealed 13 polyphenolic compounds in the leaf extracts of grain amaranth and indicated that Ar contained more rutin than the other extracts. Taken together, these results show the impact of species diversity on the phytochemical contents and bioactivities of plant extracts and suggest that the nonedible parts, such as leaves, of A. cruentus should be considered for use as crude drugs and dietary health supplements.

• International Journal of Industrial Entomology and Biomaterials
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• 제39권2호
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• pp.82-85
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• 2019

We investigated the anti-microbial activity of propolis against the pathogenic bacteria and fungi on ginseng. We selected six microbials that caused postharvest root rots in ginseng. Propolis extracts were prepared by using the ethanol extraction method. We seeded the bacteria and fungi related to ginseng disease on a specific culture medium, and treated it with propolis extracts by using the paper disc method. Propolis extracts indicate the anti-microbial activity against Paenibacillus polymyxa, Fusarium solani, Rhizoctonia solani AG-1 and Pythium ultimum. However, the anti-fungal activity of propolis is weak on Pseudomonas fluorescens subsp. Cellulosa and Colletotrichum gloeosporioides. As a result, the antimicrobial effects of propolis against microbial that prevent ginseng growth were confirmed. The antimicrobial effects are shown according to the concentration of propolis against root rot. The fungi also showed antibacterial effects in a dose-dependent manner.

• 한국응용곤충학회지
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• 제61권4호
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• pp.669-673
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• 2022

국내 생산 감로꿀의 기능성 식품 소재로 활용하기 위하여 DPPH (1,1-diphenyl-2-picryl hydrazyl)와 ABTS [2,2-azobis (3-ethylbenzothiazoline-6-sulfonate)] 라디칼 소거능, FRAP (Ferric reducing antioxidant power) 활성, 총 폴리페놀 함량 분석을 통하여 항산화 활성을 평가하였다. 국내 생산 감로꿀은 DPPH와 ABTS 라디칼 소거 활성을 보였으며 최고농도 10 mg/mL에서 DPPH에 비하여 ABTS 라디칼 소거능이 3배 이상 높게 측정되었다. FRAP 분석에서는 ferric ion (Fe³⁺)를 126 µM의 ferrous (Fe²⁺)로 환원시켰다. 또한, 국내 생산 감로꿀에 함유된 폴리페놀성 화합물의 총량은 73.41 mg GAE/kg로 확인되었다. 이상의 연구결과에 비추어 볼 때, 국내 생산 감로꿀의 우수한 라디칼 소거능과 환원력을 가지며 천연 항산화제로 알려진 페놀성 화합물을 존재로 인하여 항산화 활성을 가지는 것으로 확인되었다. 본 연구결과는 국내 생산 감로꿀의 기능성 식품 소재로 활용할 수 있는 기초자료로 제공하는 바이다.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.786-790
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• 2006

Cellular components of Lactococcus lactis ssp. lactis (heat-killed whole cells, cytoplasm, and cell walls) were tested for their in vivo immunopotentiating activity. Peritoneal macrophages from mice orally administered with heat-killed whole cells exhibited significantly greater phagocytic activity than the groups administered with cell-wall fraction or cytoplasm fraction. The cytotoxicity of natural-killer cells was the highest in the group administered with whole cells, and the production of cytokines ($IFN-\gamma$, IL-2, and IL-12) in spleen cells was significantly higher, when cellular components were injected, and it tended to be higher in the cell-wall and cytoplasm groups than in the whole-cell group. Interestingly, the cytokine production of Peyer's patch cells was high, when cytoplasm fractions were administered. These results demonstrate that whole cells and cytoplasm and cell-wall fractions of L. lactis ssp. lactis have immunopotentiating activities, which are related to the stimulation of Peyer's patches.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.172-173
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• 1998

A research collection of Pseudomons solanacearum bacteria, a pathogen causing ‘bacteria wilt’ disease of more than 265 plant species, represented for northern provinces of Vietnam has recently been established and was saved for examination of antifungal activity in their culture fluids. All strains used in this work have been isolated from infected tomato, potato, and groundnut collected from production fields and they express different levels of virulence on their host plants. Cell-free culture fluids of these strains were tested for antifungal activity (to inhibit growth of mycelium and to destroy germination tube of fungal spores) on a number of fungi that either infect or associate with vegetable crops of Solanaceae family (tomato, potato, pepers...), fruit plants (banana), and even well-known by Vietnamese traditional medicine herbal plants belonging to Trifoliatus, Schefflera, Homalomena and Panax genera (Araliaceae family) of which roots are used as a resource of the herbal material. The antifungal activity was found in nearly all strains tested. Result of study on chitin, CMC, tween 80 and casein degradation abilities of the latter suggested that antifungal activity of positively-found strains may be due to their ability of extracelluar chitinase's excretion that destroy fungal cell wall.

• The Plant Pathology Journal
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• 제17권6호
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• pp.365.3-365
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• 2001

• Asian-Australasian Journal of Animal Sciences
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• 제32권9호
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• pp.1469-1474
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• 2019

Objective: Physical activity restriction in sows may lead to behavioral abnormalities and affective disorders. However, the psychophysiological state of these sows is still unclear. As miRNAs can be used as effective markers of psychopathy, the present study aimed to assess the difference in microRNA expression between the long-term activity restricted sows and activity free sows, thus contributing to the understanding of abnormal sow behavior. Methods: Four dry sows (sixth parity, Large${\times}$White genetic line) were selected from activity restricted crates (RC) or activity free pens (FP) separately. microRNAs in the ventromedial prefrontal cortex (vMPFC) and serum were examined using real-time polymerase chain reaction, and the correlation between the miRNAs expressed in the vMPFC and serum was evaluated. Results: miR-134 (1.11 vs 0.84) and miR-1202 (1.09 vs 0.85) levels were higher in the vMPFC of the RC sows than in the FP sows (p<0.01). Furthermore, miR-132 (1.27 vs 1.08) and miR-335 (1.03 vs 0.84) levels were also higher in the RC sows than in FP sows (p<0.05); however, miR-135a, miR-135b, miR-16, and miR-124 levels were not different (p>0.05). The relative expression of serum miR-1202 was higher in the RC sows than in the FP sows (1.04 vs 0.54) (p<0.05), and there was a strong correlation (R = 0.757, p<0.05) between vMPFC and Serum levels of miR-1202. However, no significant difference was observed in miR-16 levels in the serum of the RC sows and FP sows (p>0.05). Conclusion: This pilot study demonstrates that long-term activity restriction in sows likely results in autism or other complex psychopathies with depression-like behaviors. These observations may provide new insights for future studies on abnormal behavior in sows and contribute to research on human psychopathy.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1196-1206
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• 2014

A metagenomic fosmid library was constructed using genomic DNA isolated from the gut microflora of Hermetia illucens, a black soldier fly. A cellulase-positive clone, with the CS10 gene, was identified by extensive Congo-red overlay screenings for cellulase activity from the fosmid library of 92,000 clones. The CS10 gene was composed of a 996 bp DNA sequence encoding the mature protein of 331 amino acids. The deduced amino acids of CS10 showed 72% sequence identity with the glycosyl hydrolase family 5 gene of Dysgonomonas mossii, displaying no significant sequence homology to already known cellulases. The purified CS10 protein presented a single band of cellulase activity with a molecular mass of approximately 40 kDa on the SDS-PAGE gel and zymogram. The purified CS10 protein exhibited optimal activity at $50^{\circ}C$ and pH 7.0, and the thermostability and pH stability of CS10 were preserved at the ranges of $20{\sim}50^{\circ}C$ and pH 4.0~10.0. CS10 exhibited little loss of cellulase activity against various chemical reagents such as 10% polar organic solvents, 1% non-ionic detergents, and 0.5 M denaturing agents. Moreover, the substrate specificity and the product patterns by thin-layer chromatography suggested that CS10 is an endo-${\beta}$-1,4-glucanase. From these biochemical properties of CS10, it is expected that the enzyme has the potential for application in industrial processes.

• Journal of Microbiology and Biotechnology
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• 제26권3호
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• pp.461-468
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• 2016

In recent years, various naturally occurring defence peptides such as plectasin have attracted considerable research interest because they could serve as alternatives to antibiotics. However, the production of plectasin from natural microorganisms is still not commercially feasible because of its low expression levels and weak stability. A tandemly arrayed plectasin gene (1,002 bp) from Pseudoplectania nigrella was generated using the isoschizomer construction method, and was inserted into the pPICZαA vector and expressed in Pichia pastoris. The selected P. pastoris strain yielded 143 μg/ml recombinant plectasin (Ple) under the control of the methanol-inducible alcohol oxidase 1 (AOX1) promoter. Ple was estimated by SDS-PAGE to be 41 kDa. In vitro studies have shown that Ple efficiently inhibited the growth of several gram-positive bacteria such as Streptococcus suis and Staphylococcus aureus. S. suis is the most sensitive bacterial species to Ple, with a minimum inhibitory concentration (MIC) of 4 μg/ml. Importantly, Ple exhibited resistance to pepsin but it was quite sensitive to trypsin and maintained antimicrobial activity over a wide pH range (pH 2.0 to 10.0). P. pastoris offers an attractive system for the cost-effective production of Ple. The antimicrobial activity of Ple suggested that it could be a potential alternative to antibiotics against S. suis and S. aureus infections.