• Bulletin of the Korean Chemical Society
• /
• v.32 no.11
• /
• pp.3928-3932
• /
• 2011

We synthesized peptide-resin conjugates (1 and 2) by immobilizing ${\beta}$-sheet antibacterial peptide and ${\alpha}$ helical antibacterial peptide on PEG-PS resin, respectively. Conjugate 1 showed considerable antibacterial activity in various conditions, whereas conjugate 2 did not exhibit antibacterial activity. The growths of various bacteria were inhibited by conjugate 1 even at lower concentrations than MIC. Conjugate 1 killed bacteria at MIC and had a potent synergistic effect with current antibacterial agents such as vancomycin and tetracycline, respectively. Overall results indicate that polymer surface modification using antibacterial ${\beta}$ sheet peptide is a powerful way to prevent microbial contamination on polymer surfaces.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.1
• /
• pp.161-164
• /
• 2005

• Archives of Pharmacal Research
• /
• v.15 no.2
• /
• pp.187-189
• /
• 1992

In the preceding paper, we reported the synthessis and biological properties of cephalosporins having quinoliniumthiomethyls at the C-3 position and demonstrated that quinoliniumthiomethylcephalosporins exhibited an extended antibacterial spectrum including antipseudomonal activity, especially strong antiGram-positive activity. With the aim of elaboration to optimize the antibacterial potency of the quaternary ammonium cephalosporins, we have studied the modification of substituents in the pyrrolidine ring of cefepime 1 which is characterized by its potent activity.

• Bulletin of the Korean Chemical Society
• /
• v.8 no.3
• /
• pp.189-192
• /
• 1987

The syntheses of mercaptotetrazoles and cephalothin analogs are described. Their in vitro potency was established. The compounds exhibited high antibacterial activity against Gram-positive bacteria and moderate activity against Gram-negative bacteria.

• Korean Journal of Microbiology
• /
• v.54 no.2
• /
• pp.113-125
• /
• 2018

Purpose of the present study was to investigate the factors affecting the production of antibacterial substances and histamine in rennet curd prepared by inoculation of histamine-producing lactic acid bacteria (LAB) and probiotic LAB. Probiotic Lactobacillus sakei PIL52 and Lactobacillus plantarum FIL20 produced strong antimicrobial agents against histamine-producing bacteria Lactobacillus brevis LAS129, Enterococcus faecium SBP12, and Enterococcus faecalis SBP58. The lactic acid and crude bacteriocin produced from the probiotic LAB inhibited histamine-producing bacteria in a concentration-dependent manner. As the number of probiotic LAB inoculated for the production of rennet curd increased, the antibacterial activity against histamine-producing bacteria was elevated due to the increased amount of lactic acid and crude bacteriocin in the sample. The growth of probiotic LAB as well as histamine-producing bacteria was inhibited by addition of 10% NaCl, thus the antibacterial substances and histamine contents in rennet curd were significantly lower than those of the control (P < 0.05). Meanwhile, the histamine content was not significantly increased when the rennet curd prepared by mixing probiotic LAB and histamine-producing bacteria was stored at $25^{\circ}C$ for 5 days. However, the amount of histamine detected in the rennet curd was significantly (P < 0.05) increased because the antibacterial activity of the bacteriocin produced by the probiotic LAB was decreased at $20^{\circ}C$ for 20 days.

• Microbiology and Biotechnology Letters
• /
• v.44 no.2
• /
• pp.201-207
• /
• 2016

The aim of this study was to investigate the potential of lactic acid bacteria (LAB) strains as probiotics. Two strains were isolated from healthy chicken cecum and their acid and bile tolerance, residual organic acids, antibacterial activity against pathogenic bacteria, and immunomodulation activity were measured. Identification of the isolated strains was performed using the API 50CHL system and phylogenetic analysis using 16S rDNA sequencing. The isolates were determined to be Lactobacillus sakei strains. The acid tolerance of strains L2 and L8 was high enough that 75% of the inoculum survived in pH 2 for 2 h. The bile tolerance of both strains was observed at a 1% Oxgall concentration in MRS broth. The production of organic acids (lactic acid and acetic acid) and pH changes during growth were monitored and the maximum concentrations were obtained after 48 h of incubation. Culture supernatants of the two LAB strains showed strong antibacterial activity against pathogenic bacteria. The heat-killed LAB cells also induced high levels of immune cell proliferation compared with the control, and stimulated IL-6 and TNF-α production in mouse macrophages. Therefore, L. sakei strains L2 and L8 can be considered suitable probiotic bacteria.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.567-568
• /
• 2010

• Archives of Pharmacal Research
• /
• v.13 no.4
• /
• pp.385-387
• /
• 1990

3-[(1-Methyl-1H-tetrazol-5-y)thiomethyl] is one of the most important side chains in cephaloporins. This side chain which occures in numerous antibacterial agents, suc as cefamandole, latamoxef, cefoperazone, and cefmenoxime, contributes remarkable potency and broad spectrum. For the continuous work of study on the development of broad spectrum cephalosporins, we become interested in the effect of structural modification of the substituent at the N-1 position of mercaptoterazole toward biological activity because our recent work had demonstraated that the arylsubstituted mercaptotetrazoles (Fig. 1) had favorable effect on the activity against gram-positive bacteria. The main focus of this report was to investigate the relationship between activity and functional groups in the mercaptotetrazole.

• Bulletin of the Korean Chemical Society
• /
• v.8 no.5
• /
• pp.418-421
• /
• 1987

Syntheses of cefotaxime analogs with halosubstituted phenyltetrazolthiomethyl at the $C_{3^-}$position are described. Their in vitro potency was established. The compounds exhibited a broad antibacterial spectrum. Some of these compounds showed activity against Gram-positive bacteria superior to the parent cefotaxime. Against Gram-negative bacteria, these compounds are less effective than cefotaxime.

• Journal of Dairy Science and Biotechnology
• /
• v.40 no.1
• /
• pp.23-34
• /
• 2022

In this study, to determine the importance of lactic acid bacteria (LAB) in Kombucha fermentation, biological functions, such as organic acid production and anti-inflammatory and antibacterial activities, of Kombucha, with or without LAB inoculation, were evaluated. Lactobacillus paracasei DK215, Saccharomyces cerevisiae C3, and Acetobacter pasteurianus P2 were selected as the inoculants. Organic acids were measured every 3 days from the end of fermentation using HPLC; the organic acid content of LAB-inoculated Kombucha was relatively high. Samples with or without LAB inoculation showed high antibacterial activity against Escherichia coli. The MTT assay results indicated no significant difference in concentration difference and cell death. In the NO production test, compared with the uninoculated Kombucha sample, the LAB-inoculated Kombucha sample exhibited a value similar to that of the group without LPS treatment. The levels of cytokine (IL-1α, IL-6, TNF-α) production were significantly lower than those of the LPS(+) group, indicating the anti-inflammatory activity potential of the Kombucha sample. This improvement in the biological function of the LAB-inoculated Kombucha further verifies the value of LAB in the fermented food and beverage industry.