• The Korean Journal of Pharmacology
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• v.2 no.2
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• pp.47-53
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• 1966

The bacteriostatic action of trichlorophenoxy alkylene ammonium derivatives, 2(2,4,5-trichlorophenoxy) ethylene N-triethyl ammonium bromide; (2,4,5-TETB), 2(2,4,6-trichlorophenoxy) ethylene N-triethyl ammonium bromide; (2,4,6-TETB), 2,4,5-triphenoxy ethylene pyridinium bromide; (2,4,5-TEPB), and 2,4,6-trichlorophenoxy ethylene pyridinium bromide:(2,4,6-TEPB) were observed by Jackson and Finland's and Finland's and Pak's on Staphylococcus aureus, E. coli, Salmonella typhi, Shigella flexneri, and Bacillus subtilis, comparing with those of phenol and trichlorophenol. The following results were obtained. 1) Phenol is bacteriostatic in a concentration of $10^{-3}$ for all above species. 2) Trichlorophenol is bacteriostatic in concentration of $10^{-4}$ to $5{\times}10^{-5}$ for all above species(Table 7), 3) 2,4,5-TETB and 2,4,6-TETB are bacteriostatic in a concentration of $10^{-4}$ and $5{\times}10^{-5}$ for Staphylococcus aureus, Salmonella typhi, and Shigella flexneri, but do not for E. coli and Bacillus subtilis(Table 8 and 9). 4) 2,4,5-TEPB and 2,4,6-TEPB are bacteriostatic in a concentrationof $10^{-4}$ and $5{\times}10^{-5}$ only for Staphylococcus aureus among four species(Table 10 and 11).

• Biomedical Science Letters
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• v.13 no.1
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• pp.47-53
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• 2007

Due to wide abuse of antibiotics both in human and livestock use, the advent and spread of multidrug resistant (MDR) pathogens becomes a serious health problem all over the world. Since the development of new antibiotics is at a standstill in pharmaceutical industry, the choice of therapeutic antibiotics is getting narrower. In this study, in an effort to search new antibiotics, the antimicrobial activity of Paenibacillus DY1 isolated from Korean soil was characterized on its growth inhibition spectrum against various health threatening MDR strains, with its stability and chemical structure. Extracellular culture filtrate of Paenibacillus DY1 effectively inhibits the growth of all the tested MDR enteropathogenic Eshcherichia coli, enterohemolytic E. coli, and enterotoxigenic E. coli strains, at a similar level to that on the nonresistant control E. coli strains. It showed significant growth inhibition effect against the causative agents of class one legal communicable disease, MDR Salmonella typhi, MDR Salmonella paratyphi A, food poisoning bacteria, MDR Salmonella typhimurium, and other MDR Salmonella spp. The growth of all of 10 different MDR Shigella spp. strains and 6 different Vibrio spp. strains tested was also inhibited. The antimicrobial activity of Paenibacillus DY1 was well preserved after heat treatment, and was also stable in both alkaline and acidic environment. The antimicrobial activity was partially purified with Diaion HP20 column and TLC. By NMR study, the putative structure of the activity was postulated as an alkane having hydroxyl groups.

• The Journal of the Korean Society for Microbiology
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• v.35 no.3
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• pp.225-237
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• 2000

Vibrio vulnificus, a halophilic vibrio is an estuarine gram-negative bacteria that is associated with severe and frequently fatal wound infections and life-threatening septicemia. Bacteriocins are defined as antibacterial substance produced by various species of bacteria which are usually active against closely related organisms. Bacteriocins have found widespread application in epidemiological studies as specific markers of bacteria. It was proposed by Ha et al. (1990. J. Korean. Soc. Microbiol. 25: 586.) to give the bacteriocins produced by V. vulnificus the name "vulnificins". In the present study, a total of 72 strains of V. vulnificus isolated from patients and oysters were subjected to screen potential producers and indicators of vulnificin, applying ultraviolet induction method. Sensitivity of several strains of Serratia marcesans, Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhi and Yersinia enterocolitica to vulnificins were also examined out. All the tested strains of V. vulnificus produced vulnificins active against indicator strains with various different inhibitory patterns. The spectrum of vulnificin activity and sensitive spectrum of indicator strains were considerably broad. Interestingly, almost all strains of S. marcescens, P. aeruginosa, Salmonella sp., Shigella sp. and Y. enterocolitica tested were sensitive to 1-7 vulnificin(s). Taken together, the present study demonstrated that all of the isolates of V. vulnificus produced vulnificins and that 8 good vulnificin producers and 10 good indicators were detected. These strains can be employed efficiently for establishing vulnificin typing scheme of V. vulnificus and for the detection of bacteriocinogeny and sensitivity in V. vulnificus. Biological role of vulnificin remains to be further elucidated.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.9
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• pp.1491-1499
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• 2018

Objective: This study was designed to investigate the effects of an Aspergillus sulphureus xylanase expressed in Pichia pastoris on the growth performance, nutrient digestibility and gut microbes in weanling pigs. Methods: A total of 180 weanling pigs (initial body weights were $8.47{\pm}1.40kg$) were assigned randomly to 5 dietary treatments. Each treatment had 6 replicates with 6 pigs per replicate. The experimental diets were wheat based with supplementation of 0, 500, 1,000, 2,000, and 4,000 U xylanase/kg. The experiment lasted 28 days (early phase, d 0 to 14; late phase, d 15 to 28). Results: In the early phase, compared to the control, average daily gain (ADG) was higher for pigs fed diets supplemented with xylanase and there was a quadratic response in ADG (p<0.05). In the entire phase, ADG was higher for the pigs fed 1,000 or 2,000 U/kg xylanase compared to the control (p<0.05). The gain to feed ratio was higher for pigs fed diets supplemented with 1,000 or 2,000 U/kg xylanase compared to the control (p<0.05). Increasing the amount of xylanase improved the apparent total tract digestibility of dry matter, crude protein, neutral detergent fiber, calcium, and phosphorus during both periods (p<0.05). Xylanase supplementation (2,000 U/kg) decreased the proportion of Lachnospiraceae (by 50%) in Firmicutes, but increased Prevotellaceae (by 175%) in Bacteroidetes and almost diminished Enterobacteriaceae (Escherichia-Shigella) in Proteobacteria. Conclusion: Xylanase supplementation increased growth performance and nutrient digestibility up to 2,000 U/kg. Supplementation of xylanase (2,000 U/kg) decreased the richness of gut bacteria but diminished the growth of harmful pathogenic bacteria, such as Escherichia-Shigella, in the colon.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.177-184
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• 2009

Three hundred lactic acid bacteria isolated from human feces were studied their probiotic characters to develop potential probiotics. The properties were tested on the basis of guideline for probiotic selection protocol such as tolerance for acid or bile salt, thermal stability, antimicrobial, anticancer cell, and antiviral activity. Strain Miny-148 was selected as a potential probiotic bacterium which showed resistance to low pH, bile salts and thermal stability. On the basis of fatty acid profiles and 16S rDNA sequences analysis, the strain was identified as Lactobacillus pentosus (similarity 99.9%). The strain, L. pentosus Miny-148, showed broad antimicrobial spectrum against E. coli O157:H7, Shigella flexneri, Bacillus anthracis, Staphylococcus aureus, E. coli, Vibrio cholerae, V. vulnificus, Salmonella typhimurium, and Methicillin-resistant S. aureus (MRSA). Cell-free culture supernatant of the strain also inhibited against the growth of HT-29 colon cancer cell and transmissible gastroenterits virus.

• The Journal of the Korean Society for Microbiology
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• v.19 no.1
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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.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1352-1359
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• 2020

Objective: Lactobacilli in rabbit intestine is rare and its function in rabbit gut health is not fully understood. The present study aimed to evaluate in vivo the probiotic potential of Lactobacillus casei for suckling rabbits. Methods: Two healthy 5-day-old suckling rabbits with similar weights from each of 12 New Zealand White litters were selected and disturbed to control group and treatment group. All rabbits were artificially fed. The treatment group had been supplemented with live Lactobacillus casei in the milk from the beginning of the trial to 13 days of age. At 15 days of age, healthy paired rabbits were slaughtered to collect intestinal samples. Results: i) Oral administration of Lactobacillus casei significantly increased the proportion of Lactobacilli in the total intestinal bacteria (p<0.01) and obviously reduced that of Escherichia-Shigella (p<0.01); ii) treatment increased the length of vermiform appendix (p<0.05); iii) a higher percentage of degranulated paneth cells was observed in the duodenum and jejunum when rabbits administered with Lactobacillus casei (p<0.01); and iv) the expression of toll-like receptor 9, lysozyme (LYZ), and defensin-7-like (DEFEN) in the duodenum and jejunum was stimulated by supplemented Lactobacillus casei (p<0.05). Conclusion: Orally administered Lactobacillus casei could increase the abundance of intestinal Lactobacilli, decrease the relative abundance of intestinal Escherichia-Shigella, promote the growth of appendix vermiform, stimulate the degranulation of paneth cells and induce the expression of DEFEN and LYS. The results of the present study implied that Lactobacillus casei exhibited probiotic potential for suckling rabbits.

• Journal of Microbiology
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• v.44 no.3
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• pp.327-335
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• 2006

An epidemiological survey of human enterobacterial infections was conducted to determine the prevalence of enteropathogens in the Republic of Korea during one year, 2003. We tested for infectious diseases in 26,992 stool samples obtained from people who visited clinics located in six big cities and six rural provinces. From these samples, we isolated 1,291 cases of enteritis bacterial infection (4.8%). In the urban areas, 821 cases of bacterial infection (6.4%) were identified and, in the rural areas, 479 bacterial strains (3.3%) were isolated. Seasonal patterns were seen for diarrhea associated with S. aureus, S. coli and V. parahaemolyticus, while Salmonella and Shigella infections showed slight seasonal variation. We found that S. aureus and Salmonella were more frequently isolated from children and the elderly; however, the prevalence of E. coli, V. parahaemolyticus, and Shigella were similar in different age groups. Routine monitoring of these infections is considered a worthwhile means by which to elucidate their epidemiology and modes of transmission and ultimately to control them more effectively. Continuous laboratory-based surveillance for findings of enteritis bacterial infection should be emphasized in the prevention of these infections.

• Korean Journal of Agricultural Science
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• v.21 no.1
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• pp.60-66
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• 1994

Among the various bacterial isolates from municipal sewages which utilized linear alkylbenzene sulfonate (LAS) as a sole source of carbon. 3 potent strains - KL-3, SH-2 and EN-1 - were selected. The strains were classified: KL-3 as a strain belong to the genus Klebsiella; SH-2 Shigella; and EN-1 Enterobacter, respectively. They were grown in a broth containing 200 ppm of LAS, using a laboratory scale fermentor: the bacterial growth reached stationary phase after 2 days with a maximum viability of $10^8cfu/mL$ of the culture; initial rates of LAS degradation were high during the first 24 hours of cultivation (KL-3 and SH-2, approx. 50%; EN-1, 20%); after 1 day a lag period of about 24 hours was observed for all the strains, and thereafter break-down proceeded rapidly; final rates after 7 days were approximately 85% by KL-3, 82% by SH-2 and 75% by EN-1. Adsorption of LAS by the bacterial cell mass was high for the strain SH-2, as Freundlich equation: Y= 0.030X + 0.95 was calculated.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.2
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• pp.127-134
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• 2015

We investigated the growth-inhibitory activities of cosmetics and their preservatives against pathogens and resident skin bacteria. Of the tested cosmetics, preservatives such as parabens, 1,2-hexanediol, phenoxyethanol-contained toner, emulsion, cream and baby cream exhibited potent antibacterial effects against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Parabens, 1,2-hexanediol and phenoxyethanol inhibited the growth of pathogens, as well as skin-resident bacteria such as Staphilococcus epidermidis, Shigella flexneri, Enterobacter aerogenes and so on. The application of a basic cream containing phenoxyethanol to human skin was shown to disturb the skin microbiota: at the phylum level, Proteobacteria increased and at species level, 4P004125_s increased and Propionibacterium humerusii decreased. Based on these findings, parabens, 1,2-hexanediol and phenoxyethanol have antimicrobial activity and cosmetics containing phenoxyethanol may disturb skin microbiota.