• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1793-1800
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• 2020

Bifidobacterium strains can provide several health benefits, such as antimicrobial and immunomodulatory effects. Some strains inhibit growth or cell adhesion of pathogenic bacteria, including multidrug-resistant bacteria, and their antibacterial activity can be intensified when combined with certain antibiotics. In addition, some strains of bifidobacteria reduce viral infectivity, leading to less epithelial damage of intestinal tissue, lowering the virus shedding titer, and controlling the release of antiviral substances. Furthermore, bifidobacteria can modulate the immune system by increasing immunoglobulins, and inducing or reducing pro- or anti-inflammatory cytokines, respectively. In particular, these anti-inflammatory effects are helpful in the treatment of patients who are already suffering from infection or inflammatory diseases. This review summarizes the antimicrobial effects and mechanisms, and immunomodulatory effects of Bifidobacterium strains, suggesting the potential of bifidobacteria as an alternative or complementary treatment option.

• The Korean Journal of Community Living Science
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• v.26 no.4
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• pp.697-705
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• 2015

This study investigates antimicrobial effects of food-borne pathogens and the antioxidant activity of Torreya nucifera extract. The growth of food-borne pathogens including Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans was inhibited by the extract. The antimicrobial activity of the extract was highest for Staphylococcus aureus among seven gram-positive bacteria and for Pseudomonas aeruginosa among six gram-negative bacteria. The extract exhibited slightly lower DPPH radical-scavenging activity, but its ABTS radical-scavenging activity was higher than that of ${\alpha}$-tocopherol. The results demonstrate the extract's antimicrobial effects on food-borne pathogens as well as potent antioxidant capacity and suggest that Torreya nucifera may be used as a natural antibacterial agent and an effective antioxidant in food.

• International Journal of Oral Biology
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• v.38 no.4
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• pp.149-154
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• 2013

In general, oleanolic acid (OA) and ursolic acid (UA) have antimicrobial effect against Gram-positive bacteria but not Gram-negative bacteria whereas sophoraflavanone G has antimicrobial activity against both bacterial types. However, the antimicrobial effects of OA, UA, and sophoraflavanone G against periodontopathogens have not been studied to any great extent. The aim of this study was to investigate antimicrobial effect of OA, UA, and sophoraflavanone G against 15 strains (5 species) of oral Gram-negative bacteria, which are the major causative bacteria of periodontal disease. The antimicrobial activity was evaluated by minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) determinations. OA and UA showed antimicrobial effects against all of the Porphyromonas gingivalis strains tested and also Prevotella intermedia ATCC $25611^T$. Interestingly, P. intermedia ATCC 49046 showed greater resistance to OA and UA than P. intermedia ATCC $25611^T$. In contrast, sophoraflavanone G had antimicrobial activity against all strains, with MIC and MBC values below $32{\mu}g/ml$, except Aggregatibacter actinomycetemcomitans. These results indicate that sophoraflavanone G may have potential for use in future oral hygiene products such as dentifrices and gargling solution to prevent periodontitis.

• Korean Journal of Veterinary Research
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• v.54 no.3
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• pp.159-164
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• 2014

Bacterial infection of the uterus in Hanwoo can kill embryos. Therefore, many antibiotics have been used to treat this infection in the uterus of repeat breeders. Incorrect use of antibiotics has led to resistance in bacteria. Natural compounds have used as substitutes for antibiotics because they are safe and have very mild side effects. This study was conducted to examine the antimicrobial effects of five extracts from medicinal plants including Humulus japonicas (Hj), Phelledendron amurense (Pa), Viola mandshurica (Vm), Carthamus tinctorius (Ct), and Chelidoni herba (Ch) on bacteria isolated from the uterus of Hanwoo using the paper disc diffusion method. Hj and Pa extracts had potent antimicrobial effects against Staphylococcus lentus, Streptococcus infantarius subsp. coli, and Bacillus pumilus. Pa had the greatest antimicrobial effect among the five medicinal plants and was effective against 19 types of bacteria from bovine uterus. Compared to Pa, Hj showed weaker antimicrobial effects on all the bacteria tested except Pseudomonas aeruginosa. Vm, Ct, and Ch also showed weak antimicrobial effects on the tested bacteria. The results obtained suggest that Hj and Pa are natural compounds suitable for treating bacterial infection in repeat breeders and improving conception rates of Hanwoo.

• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.19-23
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• 2010

Recently, marine organisms are emerging as a leading group for identifying and extracting novel bioactive substances. These substances are known to possess a potential regarding not only as a source of pharmaceutical products but also their beneficial effects on humans. Among the substances, antimicrobial peptides (AMPs) specifically have attracted considerable interest for possible use in the development of new antibiotics. AMPs are characterized by relatively short cationic peptides containing the ability to adopt a structure in which cationic or hydrophobic amino acids are spatially scattered. Although a few reports address novel marine organisms-derived AMPs, their antimicrobial mechanism(s) are still remain unknown. In this review, we summarized the peptides previously investigated, such as Pleurocidin, Urechistachykinins, Piscidins and Arenicin-1. These peptides exhibited significant antimicrobial activities against human microbial pathogens without remarkable hemolytic effects against human erythrocytes, and their mode of actions are based on permeabilization of the plasma membrane of the pathogen. Therefore, the study of antimicrobial peptides derived from marine organisms may prove to be useful in the design of future therapeutic antimicrobial drugs.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.1
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• pp.1-15
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• 2007

Purpose : This study was conducted to investigate the antimicrobial effects of herb for removing dampness and promoting urination against vaginal microbes. Methods : Staphylococcus aureus. Methicillin-resistant Staphylococcus aureus(MRSA), Candida albicans and Gardnerella vaginalis were used for vaginitis-induced microbes. Lactobacillus gasseri, Streptococcus spp. and Escherichia coil HB101 were used for normal vaginal florae. And herbs for removing dampness and promoting urination(Dianthi herbs. Tokoro Rhizoma, Saururi Herbs, Pyrrosiae Folium, Artemisiae Iwayomogii Herba, Plantaginis Semen, Tetrapanacis Medulla, Polygoni Avicularis Herba, Malvae Semen, Akebiae Caulis, Kochiae Fructus, Lygodii Spora) were used. Antimicrobial activities were estimated by the change of optical densities and colony test in vitro. Results : Plantaginis Semen, Artemisiae Iwayomogii Herba and Lygodii Spora had the antimicrobial susceptibility and selective toxicity against MRSA and Gardnerella vaginalis. Polygoni Avicularis Herba had the antimicrobial susceptibility and selective toxicity against Staphylococcus aureus. MRSA and Gardnerella vaginalis. Malvae Semen and Kochiae Fructus had the antimicrobial susceptibility and selective toxicity against MRSA. Dianthi Herba had the antimicrobial susceptibility and selective toxicity against Gardnerella vaginalis. Conclusion : According to these results, we can suggest that Plantaginis Semen, Artemisiae Iwayomogii Herba, Lygodii Spora, Polygoni Avicularis Herba, Malvae Semen, Kochiae Fructus and Dianthi Herba would be available to the antimicrobial agent for vaginitis-induced microbe in vitro.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.130-136
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• 2007

Artemisia capillaris THUNB is a perennial herb that belongs to the family Compositae spp and the most common plant among the various herbal folk remedies used in treatment of abdominal pain, hepatitis, chronic liver disease, jaundice and coughing in Korea. In this study, antimicrobial effects of Artemisia capillaris extracts on the food poisoning bacteria were investigated for further clinical application, which is an alternative for the use of antibiotics and their unexpected resistance. Artemisia capillaris extract using ethyl acetate showed the highest antimicrobial effects on S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus. The chloroform extract showed strong effects on all kinds of bacteria; whereas ethanol and methanol extracts showed weaker effects. Finally, ether and water extracts showed the weakest effects under the same conditions. The minimum inhibitory concentration (MIC) of ethyl acetate extract was 1 mg/mL for E. coli O157 : H7 and L. monocytogenes, and 2 mg/mL for S. enteritidis and S. aureus. The inhibitory effects on all the bacteria continued for 12 hours after incubation using 20 mg/mL and 30 mg/mL of ethyl acetate extract. The inhibitory effects continued maximally for 72 hours. The results of these studies indicate Artemisia capillaris extract exhibited excellent antimicrobial and inhibitory effects on the food poisoning pathogenic bacteria; S. enteritidis, E. coli O157 : H7, L. monocytogenes and S. aureus.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.612-617
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• 2012

The antioxidant, antimicrobial, and cytotoxic activities of ovotransferrin were investigated in vitro. The antioxidant capacity of ovotransferrin was evaluated using the 2,2-Diphenyl-1-picryl hydrazyl (DPPH) radical scavenging method, antimicrobial effects using the agar well diffusion method, and cytotoxicity using the 3-(4,5-dimethylthizol-2-yl)-2,5-diphenylatetetrazolium bromide (MTT) assay. The DPPH radical-scavenging capacity of ovotransferrin at 1 mg/mL level reached approximately 60% after 48 h of reaction. The antimicrobial effects of ovotransferrin against common food-borne pathogens, Staphylococcus aureus KCCM 32395, Bacillus cereus KCCM 40935, Listeria monocytogenes ATCC 15313, Escherichia coli O157:H7 ATCC 43895, and Helicobacter pylori HpKCTC 26695 were dose dependant. Gram-positive bacteria was more sensitive to ovotransferrin than gram-negative bacteria. Ovotransferrin showed stronger antimicrobial effect against L. monocytogenes than other gram-positive bacteria tested. The cytotoxicity of ovotransferrin was evaluated in human cancer cell lines, various tissue origins, including the larynx (Hep-2), stomach (AGS), lung (SK-MES-1), liver (HepG2), breast (MCF-7), cervix (HeLa), and colon (HT-29). Ovotransferrin displayed relatively high cytotoxicity (${\leq}60%$ inhibition effects) at 40 mg/mL. At lower concentrations (${\leq}10mg/mL$), however, ovotransferrin cytotoxic effects were not significant in all cancer cell lines tested. These results indicated that ovotransferrin has potential to be used as an antioxidant or antimicrobial agent in foods or a pharmaceutical agent against cancers.

• Food Science and Preservation
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• v.6 no.1
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• pp.110-114
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• 1999

In order to study the natural preservation of food, sixteen kinds of medicinal plants were extracted by 80% methanol and then antimicrobial activity of the extracts was investigated against various kinds of microorganisms. The extracts of medicinal plants showed good effects of antimicrobial activity against bacteria except Bacillus cereus, Escherichia coli O-157. Especially, the extracts of Artemisia annua, Aster scaber, Solidago virganrea shower good inhibitory effects on the growth of bacteria to the cooling preservation foods, and Artemisia annua was decreased of the TMA(Trimethylamine) test. the result thus indicate that Artemisia annua, Aster scaber, Solidago fischeri extract inhibitory effects on cooling preservation foods, so that it may be potential as a natural preservatives.

• The Korean Journal of Community Living Science
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• v.21 no.1
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• pp.13-18
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• 2010

This study was performed to investigate the antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens. The growth inhibitory effects of the extract at a concentration of 250, 500, 1,000 or 2,000 mg/L on food poisoning microorganism were determined against Salmonella typhimurium, Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Staphylococcus aureus. The microorganisms growth was not affected by the extract at the concentration up to 250 mg/L, but was significantly (p<0.05) inhibited by the extract at a concentration higher than 1,000 mg/L. The extract of Euphorbia humifusa had strong antimicrobial activity against all test strains at a concentration of 2,000 mg/L. The results in the present study demonstrate antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens, suggesting that Euphorbia humifusa could be an effective natural antibacterial agent in food.