• Food Science of Animal Resources
• /
• v.18 no.2
• /
• pp.157-163
• /
• 1998

This study was carried out to examine that pepsin-hydrolyzed bovine lactoferrin has applicabilities which are market milk and dairy products. The stability of pepsin-hydrolyzed bovine apo-lactoferrin and the change of its antibacterial character has been studied under various method for pasteurization (LTLT; 65$^{\circ}C$ / 30min., HTST ; 75$^{\circ}C$ / 15sec., UHT ; 135$^{\circ}C$ / 3sec.) and pH Values (pH 2.0, pH 4.0, pH 6.8). The ehated samples were assayed for minimal bacteriocidal concentrations (MBCs) and bacteriocidal effect against E. coli. The results obtained were summarized as follows: After fractionation of pepsin-hydrolyzed bovine lactofeerin by gel filtration. several peptide fractions were found that had strong antibacterial activity. SDS-PAGE showed that the one of these fractions with strong antibacterial activity, which had a molecular mass a range of 30∼33KDa. The MBCs for pepsin-hydrolyzed bovine lactoferrin fraction No. 2 against E. coli required to cause complete inhibition of growth varied within the range of 200∼400 $\mu\textrm{g}$/ml, depending on heat treatments and pH conditions. The peptide fraction No. 2 showed strong bacteriocidal activity against E. coli at LTLT and HTST treatments under acidic pH conditions. and was reduced activity at UHT treatment under pH 6.8 condition.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.18 no.7
• /
• pp.549-555
• /
• 2006

In the present study, sterilizing and antibacterial performance tests of Polybutylene pipe with nano-silver were carried out in the testing bench of water supply facilities. Experimental results show that the average sterilizing and antibacterial rate of two micro-biological samples such as E. coli and S. aureus is about 90% in case of stillness experimental condition and 99% in case of flowing experimental condition, when elapsed time is 120 hours and 3 hours, respectively. Experimental results also show that the supply water velocity in nano-silver Polybutylene pipe varies from 1 m/s to 1.5 m/s, the elapsed time needed sterilizing rate reach to 100% decreases.

• Journal of Microbiology and Biotechnology
• /
• v.18 no.5
• /
• pp.990-996
• /
• 2008

In a previous study, we found an antifungal effect on human pathogenic fungi by the cell-penetrating peptide Tat (47-58) derived from HIV-1. Tat (47-58) immediately entered into the fungal nucleus and affected some physiological changes on the intracellular condition. In this study, Tat (47-58) showed a broad spectrum of antibacterial activity against pathogenic bacteria including bacterial clinical isolates. To improve resistance against proteases for use in vivo, we synthesized an analog of Tat (47-58) by substituting the L-amino acid for the D-amino acid. The D-enantiomer of Tat (47-58) also exhibited a broad spectrum of antibacterial activity at almost the same level of L-Tat (47-58) concentration. Unlike L-Tat (47-58), D-Tat (47-58) showed a significant proteolytic resistance against all proteases tested and antimicrobial activities in the presence of trypsin. Moreover, D-Tat (47-58) inhibited MRSA infection in human HeLa cells whereas L-Tat (47-58) partially allowed MRSA infection, and the results were due to the proteolytic resistance of D-Tat (47-58).

• Journal of Microbiology and Biotechnology
• /
• v.32 no.1
• /
• pp.56-63
• /
• 2022

This study aims to determine the antibiofilm effect of cell-free supernatant (CFS) of Lactobacillus brevis strains against Streptococcus mutans strains. To study the antibiofilm mechanism against S. mutans strains, antibacterial effects, cell surface properties (auto-aggregation and cell surface hydrophobicity), exopolysaccharide (EPS) production, and morphological changes were examined. The antibiofilm effect of L. brevis KCCM 202399 CFS as morphological changes were evaluated by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM), compared with the control treatment. Among the L. brevis strains, L. brevis KCCM 202399 showed the highest antibiofilm effect on S. mutans KCTC 5458. The antibacterial effect of L. brevis KCCM 202399 against S. mutans KCTC 5458 was investigated using the deferred method (16.00 mm). The minimum inhibitory concentration of L. brevis KCCM 202399 against S. mutans KCTC 5458 was 25.00%. Compared with the control treatment, L. brevis KCCM 202399 CFS inhibited the bacterial adhesion of S. mutans KCTC 5458 by decreasing auto-aggregation, cell surface hydrophobicity, and EPS production (45.91%, 40.51%, and 67.44%, respectively). L. brevis KCCM 202399 CFS inhibited and eradicated the S. mutans KCTC 5458 biofilm. Therefore, these results suggest that L. brevis KCCM 202399 CFS may be used to develop oral health in the probiotic industry.

• International Journal of Internet, Broadcasting and Communication
• /
• v.13 no.2
• /
• pp.82-92
• /
• 2021

Purpose: It has been reported that the diversity and abundance of microbes in the vagina decrease due to the use of antimicrobial agents, and the high recurrence rate of female vaginitis due to this suggests that a new treatment is needed. Methods: In the experiment, we detected that 10% potassium sorbate solution, 1% eucalyptus oil solution, 1% tea tree oil solution, 400 µL/10 mL grapefruit seed extract solution, 100% lactic acid, 10% acetic acid solution, and 10% lactic acid solution were prepared and used. After adjusting the pH to 4, 5, and 6 with lactic acid and acetic acid in the mixed culture medium, each bacterium was inoculated into the medium and incubated for 72 h at 35℃. Incubate and 0 h each. 24 h. 48 h. The number of bacteria was measured after 72 h. Results: In the mixed culture test between lactic acid bacteria and pathogenic microorganisms, lactic acid bacteria showed good results at pH 5-5.5. Potassium sorbate, which has varying antibacterial activity based on the pH, killed pathogenic bacteria and allowed lactic acid bacteria to survive at pH 5.5. Conclusion: The formulation ratio obtained through this study could be used for the development of a feminine cleanser that can be used as a substitute for antibacterial agents. Further, the findings of this study may be able to solve the problem of antimicrobial resistance in the future.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.6
• /
• pp.881-887
• /
• 2010

This study was conducted to investigate the antibacterial activities of medicinal plant extracts. The results were as follows. Crude water and methanolic extracts of Sanguisorba officinalis Linne, Coptis chinensis Makino, and Portulaca oleracea Linne, among 31 kinds of medicinal plants, had strong antibacterial activities against S. aureus and V. parahaemolyticus, with the methanolic extract more effective than the water extract. The methnolic and water extracts of S. officinalis Linne had strong antibacterial activities against S. aureus and V. parahaemolyticus. Antibacterial activity against S. aureus and V. parahaemolyticus was observed with extracts of S. officinalis Linne at dilutions of 5 and 10%, respectively. The EtOAc, BuOH, and $H_2O$ fractions of the extract of S. officinalis Linne had antibacterial activities against S. aureus and V. parahaemolyticus. Specifically, the fractions had antibacterial activity against S. aureus at dilutions of 5, 2, and 1%, respectively. Regarding V. parahaemolyticus, the EtOAc, $H_2O$, and BuOH fractions had antibacterial activities at dilutions of 5, 2, and 1%, respectively.

• Journal of Dairy Science and Biotechnology
• /
• v.41 no.4
• /
• pp.191-202
• /
• 2023

In this study, lactic acid bacteria (LAB) was isolated from blueberries. The isolated LAB were rod-shaped and gram-positive, as shown using gram staining. In addition, the identified bacteria showed high homology to Lactiplantibacillus argentoratensis. The culture supernatant was isolated from L. argentoratensis and its antibacterial activity against the pathogenic bacteria Salmonella and Escherichia was analyzed. Culture supernatants of L. argentoratensis significantly inhibited the growth of Salmonella. Enteritidis NCCP 16947, Salmonella Typhimurium NCCP 16960, and Salmonella. Thompson NCCP 11704. Interestingly, the higher the concentration of the culture supernatant, the more significant was the antibacterial activity. Additionally, the culture supernatant of L. argentoratensis showed significant antibacterial activity against Escherichia strains. To determine whether the antibacterial substance is stable to heat and pH, the LAB culture supernatant was heat-treated under 65℃ for 30 min, 75℃ for 15 min, 85℃ for 10 min, and 100℃ for 5 min. Measurement of antibacterial activity against pathogenic strains by adding 5% of heat-treated culture medium showed the same antibacterial activity as before heat treatment. However, in a test where the pH of the culture supernatant was adjusted to 7.0 from 3.73, no antibacterial activity was observed.

• Archives of Plastic Surgery
• /
• v.37 no.2
• /
• pp.115-121
• /
• 2010

Purpose: Many topical agents had been used for contaminated wound treatment. Although antimicrobial ointments were widely used as topical agents, their comparative antibacterial and wound healing effects were largely unreported. The purpose of this study was to compare antibacterial effects and wound healing effects of common topical ointments on infected full thickness skin defect in the mouse. Methods: One full thickness skin defects in the mice (n=60) were developed on the back and left open for twenty-four hours. Sixty mice were divided into four groups: group B (dressing with Bactroban$^{(R)}$, n=15), group I (dressing with Iodosorb$^{(R)}$, n=15), group T (dressing with Terramycin$^{(R)}$, n=15), group G (control group, dressing with dry gauze, n=15). The size of wound defects and the grades of wound healing were evaluated at 4, 7, 10 days, and antibacterial effect was evaluated with restricted zone in Mueller Hinton agar by disk diffusion method. After the wound was left open for twenty-four hours, many Staphylococcus aureus was cultured. The wound defect size was decreased in order of Bactroban$^{(R)}$ (B), Iodosorb$^{(R)}$ (I), Terramycin$^{(R)}$ and gauze dressing group in all days, but difference among experimental groups was not statistically significant. The grade score of wound healing was increased in order of Bactroban$^{(R)}$, Iodosorb$^{(R)}$, Terramycin$^{(R)}$ and gauze dressing group, and the difference was statistically significant. Antibacterial effect for was increased in order of Bactroban$^{(R)}$, Iodosorb$^{(R)}$, Terramycin$^{(R)}$ and gauze dressing group, and the difference was statistically significant. Conclusion: Topical antimicrobial ointments application was effective against wound infections by S. aureus. Bactroban$^{(R)}$ may be an optimal topical treatment for infected wounds according to this study. However, further study is necessary to evaluate the clinical efficacy of antimicrobial ointments and to search for the mechanisms that explain their effects.

• The Journal of the Korea Contents Association
• /
• v.17 no.10
• /
• pp.300-306
• /
• 2017

The purpose of this study was to investigate the antibacterial effect of functional multiwall carbon nanotube (MWCNT) on the conventional glass ionomer cement(GIC). The MWCNT was incorporated into a commercial powder at 0.125, 0.25, 0.5 and 1.0 wt%. Specimens for vickers hardness(VHN) disks(Ø$10mm{\times}2mm$) each were prepared. Indention were made using a load of 200 N and 20 s dwell on four specimens for each distilled water storage time 1d, 7d, and 14days. The antibacterial effects using agar diffusion test with S. mutans and S. aureus. The diameters of the inhibition zones produced around the materials were measured. The results revealed that all the vickers hardness values were increase significantly with incubation time(p<0.05). Regarding the antibacterial effect for S. mutans, all the tested groups showed a slightly higher value not significantly with the control group(p<0.05). However S. aureus statistical analysis indicated a significant difference for antibacterial agents between control and MWCNT containing 0.25 wt%(p<0.05). These results of this study provide that the conventional GIC with containing MWCNT show good antibacterial effect against and favorable mechanical properties. Further this study on the efficient functionalization of multiwall carbon nanotube will be needed.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.44 no.1
• /
• pp.1-7
• /
• 2018

In this study, 1,2-hexanediol, ethylhexylglycerin, and glyceryl caprylate known as skin conditioning agents with antimicrobial activity in cosmetics were investigated for their antimicrobial activity against gram-positive and gram-negative bacteria when combining them with various ingredients in cosmetic formulations. Seven kinds of substances expected to improve the antibacterial activity in formulations were selected to blend with these three compounds.; 1,3-propanediol, 1,3-butanediol, glycerin, dipropylene glycol, niacinamide, EDTA-2Na, and ethanol. The checkerboard assay was conducted to confirm the antibacterial synergy of these seven substances and the three skin conditioning agents. Consequently, ethanol and EDTA-2Na were detected as the significant materials with synergistic effect as well as ethanol showed antibacterial synergy with all the three compounds. When seven of selected materials were mixed with glyceryl caprylate, there were synergistic or additive activity against S. aureus, gram-positive bacteria and it was suggested that the combination with 1,2-hexanediol and glyceryl caprylate was useful to control both gram-positive and gram-negative bacteria when there were four kinds of polyols. This study is meaningful in that it confirmed the antibacterial synergy of the skin conditioning agents with antimicrobial activity and the main raw materials frequently used in cosmetics, thereby contributing to prediction of the antibacterial activity of the skin conditioning agents in cosmetic formulations.