• The Plant Pathology Journal
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• 제38권6호
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• pp.646-655
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• 2022

Pepper mild mottle virus (PMMoV), one of the most prevalent viruses in chili pepper (Capsicum annuum L.) is a non-enveloped, rod-shaped, single-stranded positive-sense RNA virus classified in the genus Tobamovirus. The supernatants of five bacterial cultures (Pseudomonas putida [PP], Bacillus licheniformis [BLI], P. fluorescens [PF], Serratia marcescens [SER], and B. amyloliquifaciens [BA]) were analyzed to find novel antiviral agents to PMMoV in chili pepper. Foliar spraying with supernatants (1:1, v/v) obtained from Luria-Bertani broth cultures of PP, BLI, PF, SER, and BA inhibited PMMoV infection of chili pepper if applied before the PMMoV inoculation. Double-antibody sandwich enzyme-linked immunosorbent assay showed that treatments of five supernatants resulted in 51-66% reductions in PMMoV accumulation in the treated chili pepper. To identify key compounds in supernatants of PP, BLI, PF, SER, and BA, the supernatants were subjected to gas chromatography-mass spectrometry. The 24 different types of compounds were identified from the supernatants of PP, BLI, PF, SER, and BA. The compounds vary from supernatants of one bacterial culture to another which includes simple compounds-alkanes, ketones, alcohols, and an aromatic ring containing compounds. The compounds triggered the inhibitory effect on PMMoV propagation in chili pepper plants. In conclusion, the cultures could be used to further conduct tissue culture and field trial experiments as potential bio-control agents.

• Journal of Microbiology
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• 제39권2호
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• pp.146-148
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• 2001

Lactobacillus crispatus ATCC 33820 and L. gasseri ATCC 33323 were grown in MRS broth (pH 6.5) at 37$^{\circ}C$ for 24 h and the antibacterial activities of cell free culture supernatants were determined by the agar well diffusion method. The culture supernatants were inhibitory to Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Pediococcus acidilacticii, and Lactobacillus helveticus. The supernatants did not show any lysozyme activity. Addition of catalase did not affect the antibacterial activities of the supernatants. The antibacterial substances were heat stable (100$^{\circ}C$ for 60 min) and sensitive to proteases.

• Asian Pacific Journal of Cancer Prevention
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• 제15권10호
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• pp.4255-4259
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• 2014

Lactobacilli are probiotics shown to have antitumor activities. In addition, they can regulate gene expression through epigenetic mechanisms. In this study, we aimed to assess anti tumor activities of Lactobacillus acidophilus and Lactobacillus crispatus on the MDA-MB-231 breast cancer cell line. The effects of culture supernatants were determined by MTT [3-(4,5-dimethylthiazol-2-y-2,5-diphenyltetrazolium bromide] assay. Changes in expression of 5 cancer-testis antigens (CTAs), namely AKAP4, ODF4, PIWIL2, RHOXF2 and TSGA10, were analyzed by quantitative real time RT-PCR. The culture supernatants of the 2 lactobacilli inhibited MDA-MB-231 cell proliferation. In addition, transcriptional activity of all mentioned CTAs except AKAP4 was significantly decreased after 24 hour treatment with culture supernatants. This study shows that Lactobacillus acidophilus and Lactobacillus crispatus have antiproliferative activity against MDA-MB-231 cells. In addition, these lactobacilli could decrease transcriptional activity of 4 CTAs. Previous studies have shown that expression of CTAs is epigenetically regulated, so it is possible that lactobacilli cause this expression downregulation through epigenetic mechanisms. As expression of CTAs in cancers is usually associated with higher grades and poor prognosis, downregulation of their expression by lactobacilli may have clinical implications.

• Restorative Dentistry and Endodontics
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• 제22권2호
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• pp.761-768
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• 1997

Microorganisms and their by-products are considered to be the major causes of pulpal and periapical pathosis. The role of microorganisms in endodotic infection has been studied regarding the prevalence of particular organisms found in root canal and periapical lesions. The aim of this study was to investigate the effect of culture supernatants of several oral microorganims isolated from infected root canals on the viability of cultured cell lines using colorimetirc assay. S. simulans, S. sciuri, E. faecium, S. intermedius, S. mitis, S. sanguis and S. uberis were incubated in Todd-Hewitt broth for 16 hours. 20 and 100ul of filtered bacterial cell culture supernatants were added to MK and Hep-2 cells. Cell viability was measured using MIT colorimetric assay. 20ul and 100u1 of S. sanguis supernatant showed significant cytotoxicity compared to control on MK cells. 100ul of S. sanguis supernatant significantly depressed viability of HEp-2 cells. E. faecium and S. intermedius did not affect the viability of MK and HEp-2 cells.

• Journal of Microbiology and Biotechnology
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• 제32권1호
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• pp.64-71
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• 2022

The discarding of wastes into the environment is a significant problem for many communities. Still, food waste can be used for lactic acid bacteria (LAB) growth. Here, we evaluated three growth media equivalent to de Mann Rogosa Sharpe (MRS), using apple bagasse, yeast waste, fish flour, forage oats, and cheese whey. Cell-free supernatants of eight LAB strains were tested for antimicrobial activity against nine indicator microorganisms. The supernatants were also evaluated for protein content, reducing sugars, pH, and lactic acid concentration. Cell-free supernatants from fish flour broth (FFB) LAB growth were the most effective. The strain Leuconostoc mesenteroides PIM5 presented the best activity in all media. L. mesenteroides CAL14 completely inhibited L. monocytogenes and strongly inhibited Bacillus cereus (91.1%). The strain L. mesenteroides PIM5 consumed more proteins (77.42%) and reducing sugars (56.08%) in FFB than in MRS broth (51.78% and 30.58%, respectively). Culture media formulated with agroindustrial wastes positively improved the antimicrobial activity of selected LAB, probably due to the production of antimicrobial peptides or bacteriocins.

• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1613-1621
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• 2006

Isolation and identification of algal lytic bacteria were carried out. Nine strains of algal lytic bacteria were isolated by the double-layer method using Anabaena flos-aquae as a sole nutrient. The isolate, AFK-13, showing the highest algal lytic activity was identified as Sinorhizobium kostiense based on the l6S rDNA sequence. The algal lytic experiments of the culture supernatants of AFK-13 demonstrated that the bacterial cell growth reached a maximum at 36-h culture, but the supernatant of 72-h culture exhibited the highest activity. Components among the extracellular products in the crude enzyme of the supernatant from S. kostiense AFK-13 culture were responsible for degradation of cell walls of Anabaena flos-aquae. Algal lytic assay tests of the culture supernatants suggest that the main substances for algal lytic activity could be proteinaceous. The activity of glucosidase was observed highly by polysaccharolytic analysis using the crude enzyme from S. kostiense AFK-13, whereas activities of galactosidase, mannosidase, rhamnosidase, and arabinosidase were also detected in low levels. The molecular weights (MW) of ${\alpha}-\;and\;{\beta}$-glucosidases were estimated to be approximately 50-100 kDa by the ultrafiltration method.

• 한국임상수의학회지
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• 제37권5호
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• pp.249-254
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• 2020

Neutrophil extracellular trap (NET) formation is an immune response for the invasion of microbes. The purpose of this study is to examine the effect of zinc on NET formation of porcine peripheral blood polymorphonuclear cells (PMNs). The NET formation of PMNs was measured by fluorescence microplate reader. The production of tumor necrosis factor (TNF)-α in the culture supernatants from zinc-treated peripheral blood mononuclear cells (PBMCs) was measured by enzyme-linked immunosorbent assay (ELISA). Zinc itself did not have no effect on NET formation. However, the NET formation of PMNs was increased by culture supernatants from PBMCs treated with zinc. Also, the NET formation of PMNs was increased by recombinant porcine (rp) TNF-α. The production of TNF-α in PBMCs culture supernatants was shown to increase upon zinc treatments. These NET formations of PMNs increased by either culture supernatant from PBMCs treated with zinc or rpTNF-α were inhibited by treatment of anti-rpTNF-α polyclonal antibody (pAb). These results suggested that zinc has an immunostimulating effect on the NET formation of PMNs, which is mediated by TNF-α released from zinc-treated PBMCs. Therefore, zinc may play an important role for NET formation in the defense of porcine inflammatory diseases.

• 대한수의학회지
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• 제36권3호
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• pp.647-655
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• 1996

To establish the effective ways to prevent bovine mastitis, the study has been performed to investigate the attributable factors causing down-regulation of immune responses in mammary gland of non-lactating cows. Lymphocytes from peripheral blood and mammary gland secretions(MGS) were obtained from normal healthy cows and mastitic cows, respectively. Lymphoblastogenesis were investigated carefully by adding different concentrations of supernatants collected from pure-cultures of neutrophils seperated from peripheral blood and MGS, respectively. The results obtained are as follows ; 1. Lymphoblastogenesis activity stimulated by Con A, PWM and PHA were significantly reduced in MGS from mastitic cows. 2. Supernatants collected from pure-culture of neutrophils separated both from peripheral blood and MGS showed inhibitory effect on mitogenic lymphoblastogenesis. 3. Supernatants from mammary gland neutrophils have shown 7 times more inhibitory activity than those from peripheral blood and this inhibitory effect was increased in proportion to increasing concentrations of supernatants when those were added to lymphoblast cells in culture.

• 대한미생물학회지
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• 제19권1호
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• pp.41-48
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• 1984

The present study was undertaken to elucidate the antibacterial spectrum of L. casei phage type $J_1$ strain isolated from a fermented milk product against pathogenic enteric bacteria. Growth inhibitory effects and minimum inhibitory concentration(MIC) of culture supernatants of L. casei grown in MRS broth were measured by both plate culture method and microplate broth dilution technique against Salmonella typhi, Salmonella typhimurium, Shigella flexneri, Shigella dysenteriae, enterpathogenic E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The results are summarized as follows: 1. The MRS broth culture of L. casei gave a similar extent of growth inhibitory effects against S. typhi, S. typhimurium, S. flexneri, S. dysenteriae, E. coli, K. pneumoniae and P. aeruginosa, respectively. 2. The inhibitory effects of L. casei culture were observed either in whole broth culture or in culture supernatant, but neither the bacterial suspension nor the neutralized culture supernatant showed such as antibacterial activities. 3. The MIC titres of the culture supernatants were ${\log_2}5$ to ${\log_2}6$, whereas those of the neutralized culture supernatant dropped markdely to ${\log_2}2$ to ${\log_2}3$. These results indicated that major portion of growth inhibitory effects of MRS broth culture of L. casei against enteric bacterial pathogens was possibly due to the acids produced, and minor portion to other antibacterial substances.

• 한국식품저장유통학회지
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• 제14권6호
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• pp.681-687
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• 2007

동충하초 20여종의 균사와 배양 배지를 이용하여 생물학적 활성 효과를 항산화와 항암 실험을 통하여 알아보았다. 항산화 활성 실험 DPPH와 FRAP실험을 실시하였는데 다수의 동충하초 추출물에서 항산화 활성을 확인할 수 있었으며, 시간에 따른 FRAP활성에서는 배양배지에서 균사체 추출물보다 높은 활성을 나타내었다. NOS와 관련성을 확인하기 위하여 NO활성 실험을 한 결과 NO활성은 추출물의 종류에 따라 증가 또는 감소시키는 것을 알 수 있었다. 염증과의 관련성을 확인하기 위하여 Cox-2 promoter활성실험을 한 결과, 종에 따라 활성의 증가 또는 감소는 다양하게 나타났다. Wound healing assay를 이용하여 항암효과를 알아본 결과 많은 종에서 세포의 운동성을 억제하는 효과를 가지는 것으로 나타났다. 또한 혈관생성 억제효과를 알아보기 위하여 HUVECs를 이용하여 tube formation을 확인해 본 결과 다수의 추출물에서 혈관생성을 억제하는 것으로 나타났다.