• Journal of Life Science
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• v.14 no.6 s.67
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• pp.951-962
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• 2004

Hot water extracts of 141 indigenous plants were screened for antibacterial activity against 7 Gram (+) and 12 Gram (-) bacteria by agar diffusion method. Of the 141 plants tested, 55 showed antibacterial activity against one or more species of Gram (+) bacteria and especially extracts of Oenothera stricta Ledebour (Onagraceae), Quercus variabilis Blume (Fagaceae), Alnus firma (Betulaceae), Geranium thunbergii (Geraniaceae), Lagerstroemia indica (Lythraceae) showed broad spectrum antibacterial activity on over 6 strains. Of the 141 plants tested, 45 showed antibacterial activity against one or more species of Gram (-) bacteria and especially extracts of Oenothera stricta Ledebour (Onagraceae), Punica granatum (Lythraceae), Quercus variabilis Blume (Fagaceae), Schizandra chinensis Baillon (Magnoliaceae), Alnus firma (Betulaceae), Alnus hirsuta (Betulaceae), Magnolia kobus (Magnoliaceae) showed broad spectrum antibacterial activity on over 8 strains. The most active antibacterial plants were Oenothera stricta Ledebour (Onagraceae), Punica granatum (Lythraceae), Quercus variabilis Blume (Fagaceae), Schizandra chinensis Baillon (Magnoliaceae) which are edible as permitted by Korea Food & Drug Adminstration. With in-depth research, the hot water extracts of these plants can be applied as food preservatives and alternatives of antimicrobials for livestock feeds.

• Journal of Microbiology and Biotechnology
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• v.30 no.4
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• pp.526-532
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• 2020

A bacterial strain, designated B301^T and isolated from raw chicken meat obtained from a local market in Korea, was characterized and identified using a polyphasic taxonomic approach. Cells were gram-negative, non-motile, obligate-aerobic coccobacilli that were catalase-positive and oxidase-negative. The optimum growth conditions were 30℃, pH 7.0, and 0% NaCl in tryptic soy broth. Colonies were round, convex, smooth, and cream-colored on tryptic soy agar. Strain B301^T has a genome size of 3,102,684 bp, with 2,840 protein-coding genes and 102 RNA genes. The 16S rRNA gene analysis revealed that strain B301^T belongs to the genus Acinetobacter and shares highest sequence similarity (97.12%) with A. celticus ANC 4603^T and A. sichuanensis WCHAc060041^T. The average nucleotide identity and digital DNA-DNA hybridization values for closely related species were below the cutoff values for species delineation (95-96% and 70%, respectively). The DNA G+C content of strain B301^T was 37.0%. The major respiratory quinone was Q-9, and the cellular fatty acids were primarily summed feature 3 (C_16:1 ω6c/C_16:1 ω7c), C_16:0, and C_18:1 ω9c. The major polar lipids were phosphatidylethanolamine, diphosphatidyl-glycerol, phosphatidylglycerol, and phosphatidyl-serine. The antimicrobial resistance profile of strain B301^T revealed the absence of antibiotic-resistance genes. Susceptibility to a wide range of antimicrobials, including imipenem, minocycline, ampicillin, and tetracycline, was also observed. The results of the phenotypic, chemotaxonomic, and phylogenetic analyses indicate that strain B301^T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter pullorum sp. nov. is proposed. The type strain is B301^T (=KACC 21653^T = JCM 33942^T).

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.377-387
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• 2020

This study is a retrospective and descriptive research to identify the factors affecting development of spontaneous abortion in women of childbearing age. The subjects totaled 198 females aged 20~45 who had experienced childbirth or spontaneous abortion at least once, and data was collected for one month since July 2019 through self-reporting questionnaires. The results showed that the factors affecting development of spontaneous abortion were use of panty liners (daily: reference, 1~2 times a week: B=-1.74, no: B=-0.77) and antimicrobials (often or a lot: reference, small or normal: B=-0.71, no: B=0.79), occupational groups (inoccupation: reference, service industry employee: B=0.73, white collar: B=1.22, professional: B=0.63, manager: B=1.54), and exposure-risk behavior toward endocrine-disrupting chemicals (B=0.81) during pregnancy, and their explanatory power for development of spontaneous abortion was 24.4% (R²=.24). As a result, it is necessary to prevent endocrine-disrupting chemicals exposure and pay attention to the occupational environment during pregnancy in order to reduce the development of spontaneous abortion.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.423-432
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• 2018

This study was performed to develop a new natural antimicrobial materials by analyzing the effect of extracts obtained from Ten Lauraceae Species on the inhibitory activity against Propionibacterium acnes. The plant materials were collected from Wando and Jeju islands, and the antimicrobial activity of the crude extracts was examined by the agar diffusion method with different part (i.e., leaf and branch), solvents (i.e., distilled water, 80% ethanol, and 100% methanol) and at different ultrasonic extracting times (i.e., 15, 30, and 45 minutes). The control agents used were synthetic antimicrobials, methylparaben and phenoxyethanol, at concentrations of 0.4, 1, 2, and 4 mg/disc. Altogether, extracts of 10 species used in the study showed inhibitory activity, which confirmed their antimicrobial action against acnes. Among these, leaves of Laurus nobilis L. which was extracted in 80% ethanol for 45 min showed the largest clear zone (19.8 mm). Leaves of L. nobilis L., showing highest antimicrobial activities among 10 species, were successively reextracted with n-hexane, chloroform, ethylacetate and n-butanol. As a results, in all fractions except butanol, clear zone above 10 mm were formed. The ethyl acetate fraction showed the highest inhibitory activity (13.3 mm) and the inhibitory activity was significantly higher than that of crude extract (10.2 mm) and phenoxyethanol as a control (12.5 mm).

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.556-562
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• 2007

A total of 126 crossbred weanling pigs (average body weight of $6.3{\pm}0.3$ kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, nutrient digestibility, pH of gastro-intestinal tract (GI), intestinal and fecal microflora of young piglets. Pigs were allocated to three dietary treatments based on body weight and gender in a single factorial arrangement. Treatments were control (No COS), T1 (0.2% COS during starter (6-13 kg) and 0.1% COS during grower (13-30 kg) phases, and T2 (0.4% COS during starter (6-13 kg) and 0.3% COS during grower (13-30 kg) phases, respectively. Each treatment had 3 replicates and 14 pigs were raised in each pen. COS is a low molecular weight water-soluble chitosan that can be obtained from chitin of the crab shell after deacetylation with concentrated sodium hydroxide at high temperature and then further decomposition by chitosanase enzyme in the presence of ascorbic acid. For the starter and grower periods, there were no significant differences (p>0.05) in average daily gain (ADG) and feed to gain ratio among treatments. However, during the overall period (6-30 kg), T2 showed better (p<0.05) feed to gain ratio than other treatments. A digestibility study was conducted at the end of grower phase which showed improvement (p<0.05) in DM and crude fat digestibility in T2 over the control. At 25 kg body weight, 6 pigs per treatment (2 per replicate) were sacrificed to determine the effect of diets on pH and microbial count at different sections of the GI tract. The pH of the cecal contents in pigs fed 0.1% COS was higher (p<0.05) than in the other treatments. Total anaerobic bacterial number increased from cecum to rectum in all treatments. The weekly total bacterial counts showed higher (p<0.05) in feces of pigs fed COS than that of untreated pigs at the $8^{th}$ week. The number of fecal E. coli in untreated pigs at $4^{th}$ wk was 7.35 log CFU/g compared to 6.71 and 6.54 log CFU/g in 0.1 and 0.3% COS-treated pigs, respectively. Similarly, at $8^{th}$ wk, fecal clostridium spp. were lower in pigs fed 0.3% COS (5.43 log CFU/g) than in untreated pigs (6.26 log CFU/g). In conclusion, these results indicated that chito-oligosaccharide could improve feed efficiency in young pigs and inhibited the growth of harmful bacteria.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.3
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• pp.382-392
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• 2012

This study evaluated the effects of dietary anticoccidial drugs plus antibiotic growth promoters (AGPs) on parameters of immunity in commercial broiler chickens. Day-old chicks were raised on used litter from a farm with endemic gangrenous dermatitis to simulate natural pathogen exposure and provided with diets containing decoquinate (DECX) or monensin (COBN) as anticoccidials plus bacitracin methylene disalicylate and roxarsone as AGPs. As a negative control, the chickens were fed with a non-supplemented diet. Immune parameters examined were concanavalin A (ConA)-stimulated spleen cell proliferation, intestine intraepithelial lymphocyte (IEL) and spleen cell subpopulations, and cytokine/chemokine mRNA levels in IELs and spleen cells. ConA-induced proliferation was decreased at 14 d post-hatch in DECX-treated chickens, and increased at 25 and 43 d in COBN-treated animals, compared with untreated controls. In DECX-treated birds, increased percentages of $MHC2^+$ and $CD4^+$ IELS were detected at 14 d, but decreased percentages of these cells were seen at 43 d, compared with untreated controls, while increased $TCR2^+$ IELs were evident at the latter time. Dietary COBN was associated with decreased fractions of $MHC2^+$ and $CD4^+$ IELs and reduced percentages of $MHC2^+$, $BU1^+$, and $TCR1^+$ spleen cells compared with controls. The levels of transcripts for interleukin-4 (IL-4), IL-6, IL-17F, IL-13, CXCLi2, interferon-${\gamma}$ (IFN-${\gamma}$), and transforming growth factor${\beta}$4 were elevated in IELs, and those for IL-13, IL-17D, CXCLi2, and IFN-${\gamma}$ were increased in spleen cells, of DECX- and/or COBN-treated chickens compared with untreated controls. By contrast, IL-2 and IL-12 mRNAs in IELs, and IL-4, IL-12, and IL-17F transcripts in spleen cells, were decreased in DECX- and/or COBN-treated chickens compared with controls. These results suggest that DECX or COBN, in combination with bacitracin and roxarsone, modulate the development of the chicken post-hatch immune system.

• Korean Journal of Veterinary Service
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• v.33 no.3
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• pp.241-248
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• 2010

The present study was conducted to investigate isolation and antimicrobial resistance ratio of E. coli, E. faecium and E. faecalis from feces(l50 samples) and carcasses (150 samples) on slaughtered pigs from 6 slaughterhouse of 13 cities in the Gyeongnam during the period from January 2009 to December 2009. Isolation ratio of E. coli from feces and carcasses were 98 (65.3%) and 110(73.3%), respectively, and simultaneously, E. faecalis and E. faecium from feces and carcasses were isolated 21 (14%), 52(34.7%) and 18(12%), 14 (9.3%), respectively. All E. coli isolated from feces and carcasses except cefepime (0%) and ceftiofur (0%) were exhibited 2.4~83.6% of resistance to teteracycline (83.6%), ampicillin (68.2%), streptomycin (60%), chloram-phenicol (53.8%) and cephalothin (2.4%). All E. faecalis isolated from feces and carcasses except penicillin(0%) and vancomycin (0%) were exhibited 2.7~80.8% of resistance to teteracycline (80.8%), quinupristin/dalfopristin (78%), erythromycin (56.1%), streptomycin (43.8%) and bacitracin (2.7%). All E. faecium isolated from feces and carcasses except gentamicin (0%), vancomycin (0%), florfenicol (0%), linezloid (0%) and bacitracin (0%) were exhibited 3.1~53.1% of resistance to rifampin (53.1%), erythromycin and tetracycline (25%), penicillin (15.6%), ciprofloxacin (9.3%), and streptomycin, chloramphenicol, and quinupristin/dalfopristin (3.1%). According to the heard size, resistance ratio of E. coli strains isolated from feces and carcasses in slaughtered pigs-breeding farms over 1,500 heard to tetracycline, ampicillin, streptomycin and chloramphenicol showed higher resistance ratio (1.0~16.8%) than those of farms-breeding under 1,500 heard. From the our results, we suggest that a few of antimicrobials were used in the Gyeongnam than the other cities.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.47-53
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• 2011

Salmonella enterica serovar Typhimurium (ST) is one of the most common serovars isolated from humans and animals. It has been suggested that ST infections in Koreans are largely due to the consumption of contaminated pork and beef. To investigate the genotypes, phage types, and antimicrobial resistance patterns for ST isolates of different origins, a total of 70 ST strains, including 19 isolates from humans, 44 isolates from pigs, and 6 isolates from cattle, were analyzed using pulsedfield gel electrophoresis (PFGE), phage typing, and antimicrobial susceptibility tests. Forty-three distinct PFGE patterns were generated from 70 ST isolates, which were grouped into 14 PFGE groups (from A to N) at the level of 75% similarity. The most prevalent group was the A (A1-A17 subtypes) group, encompassing 54.5% (38/70) of ST isolates. ST isolates from pigs and cattle mostly belong to groups A and L, whereas ST isolates from humans mostly belong to groups F and C. Antimicrobial susceptibility tests using 11 antimicrobial agents showed that resistance to tetracycline (TE) (81.4%) was highly prevalent, followed by streptomycin (S) (64.3%) and nalidixic acid (NA) (31.4%) resistance. A total of seventeen antimicrobial resistance patterns were observed. Only 8.6% of isolates, including a reference strain, were susceptible to all antimicrobial agents tested. The most prevalent resistance pattern was TE-S (37.1%), which was seen in 66.6% of bovine, 40.8% of swine and 21.1% of human isolates. Three ST isolates from humans (15.9%) showed resistance to 7-8 antimicrobials. The most predominant phage type (PT) was U302 (64.3%), followed by DT170 (10.0%). PFGE types did not coincide with antimicrobial resistance patterns and phage types; therefore, the combination of those types allowed for further differentiation between tested ST isolates.

• The Korea Journal of Herbology
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• v.31 no.5
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• pp.93-98
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• 2016

Objectives : Hwangheuk-san is a complex prescription composed of oriental traditional medicine and has been reported for antioxidant, antimicrobial and anticancer effects in the recent study. Methicillin-resistant Staphylococcus aureus (MRSA) is one of important causes of fatal infectious diseases such as septicemia, endocarditis, toxic shock syndrome, pneumonia, skin and soft tissue infections (SSTIs). S. aureus is reported as being for a variety of human diseases and its epidemiological relevance is mainly due to their ability of becoming highly resistant to common antimicrobials such as tetracycline, penicillin, cphalosporin and aminoglycoside. The objective of this study is to determine the antimicrobial effect of Hwangheuk-san ethanol extracts (HHS) and synergistic effects with antibiotics oxacillin against MRSA.Methods : The antimicrobial activity of HHS was measured by the disc diffusion method, broth microdilution method and the checkerboard dilution test, time-kill curve assay was performed to investigate synergistic effects with antibiotics oxacillin against MRSA.Results : HHS showed antimicrobial activity against MRSA with a MIC value of 125 ㎍/㎖. In the checkerboard test, the interaction of HHS with antibiotics oxacillin produced almost synergy or partial synergy against MRSA. This study showed that HHS reduced the MICs of oxacillin tested, and a remarkable antibacterial effect of HHS, with membrane permeability enhancers.Conclusions : These results suggest that HHS has the antimicrobial effect and synergistic effects with antibiotics oxacillin against MRSA. This study thus can be a valuable source for the development of a new drug with low MRSA resistance.

• Journal of Veterinary Clinics
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• v.27 no.1
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• pp.17-22
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• 2010

The natural herbal antimicrobial additive, Flavo-$SK^{TM}$, was developed by Zoonosis Research Center of Wonkwang University. The purpose of this study was to evaluate the effects of Flavo-$SK^{TM}$ on the health status and performance of growing chickens. This study was conducted on the growing chickens (n=20,000) for 31 days in a growing chickens husbandry. The animals were divided with two groups; Flavo-$SK^{TM}$ treated group (n=10,000) and commercial diet feeding group (n=10,000). The Flavo-$SK^{TM}$ treated animals had provided with commercial diet adding the Flavo-$SK^{TM}$ as 0.29%. During the study period, we compared clinical signs, weight increase rate, diet consumption amount, gross finding, necropsy findings and histopathological findings between the treated group and non treated group. As the results of this clinical trial, the natural herbal antimicrobial additive, Flavo-$SK^{TM}$, showed the effects on disease reduction. It is suggested that Flavo-$SK^{TM}$ has the antimicrobial effects.