• The Journal of Korean Medicine
• /
• v.23 no.3
• /
• pp.223-232
• /
• 2002

Objectives : Methicillin-resistant Staphylococcus aureus (MRSA) CCARM 3251 and S. aureusKCTC 1928 have been known to be resistant to many kinds of antibiotics. The extract of Glycyrrhizae Radix showed antibacterial activity against MRSA and antibiotics-resistant S. aureus. Methods : We examined the effects of the water-soluble extract and the methanol-soluble extract of Glycyrrhizae Radix on MRSA and antibiotic-resistant S. aureus. The methanolic extract was further fractionated with organic solvents such as hexane, chloroform, and ethyl acetate in that order. Results and Conclusions : The methanol-soluble extract of Glycyrrhizae Radix showed relatively high antibacterial activity against MRSA and antibiotic-resistant S. aureus. However, the water-soluble extract of Glycyrrhizae Radix showed no antibacterial activity against MRSA and antibiotic-resistant S. aureus. Among the fractions tested, the chloroform fraction showed the highest antibacterial activity against MRSA and antibiotic-resistant S. aureus. The methanol-soluble extract of Glycyrrhizae Radix minimal inhibitory concentrations (MICs) against MRSA and antibiotics-resistant S. aureus were $5{\;}mg/m{\ell}$ in both. The methanol-soluble extract of Glycyrrhizae Radix was separated using thin-layer chromatography and detected with UV -detector. Further study should be carried out to identify which effects cell growth inhibition of MRSA and antibiotics-resistant S. aureus.

• Food Science and Biotechnology
• /
• v.16 no.4
• /
• pp.621-625
• /
• 2007

Staphylococcus aureus in Korean kimbab rolls was monitored seasonally in 4 major cities of Korea to investigate the risk of S. aureus in a pre-prepared meal. Thirty-five (28.6%) of 105 kimbab rolls purchased in winter were contaminated with S. aureus with an average level of 2.6 log CFU/g. Thirty-six (33.0%) of 109 kimbab rolls purchased in summer and autumn were contained S. aureus with an average level of 2.9 log CFU/g. Kimbab purchased in snack bars showed higher S. aureus contamination rates with the maximum level of 4.7 log CFU/g than that purchased in convenience stores. Of the raw materials in kimbab, uncooked perilla leaf had the highest contamination rate of S. aureus. Less than 50% of S. aureus isolated from kimbab produced enterotoxin and most of the staphylococcal enterotoxin produced by S. aureus in kimbab was type A.

• Journal of Microbiology and Biotechnology
• /
• v.34 no.4
• /
• pp.795-803
• /
• 2024

Microorganisms usually coexist as a multifaceted polymicrobial community in the natural habitats and at mucosal sites of the human body. Two opportunistic human pathogens, Pseudomonas aeruginosa and Staphylococcus aureus commonly coexist in the bacterial infections for hospitalized and/or immunocompromised patients. Here, we observed that autolysis of the P. aeruginosa quorum-sensing (QS) mutant (lasRmvfR) was suppressed by the presence of the S. aureus cells in vitro. The QS mutant still displayed killing against S. aureus cells, suggesting the link between the S. aureus-killing activity and the autolysis suppression. Independent screens of the P. aeruginosa transposon mutants defective in the S. aureus-killing and the S. aureus transposon mutants devoid of the autolysis suppression revealed the genetic link between both phenotypes, suggesting that the iron-dependent metabolism involving S. aureus exoproteins might be central to both phenotypes. The autolysis was suppressed by iron treatment as well. These results suggest that the interaction between P. aeruginosa and S. aureus might be governed by mechanisms that necessitate the QS circuitry as well as the metabolism involving the extracellular iron resources during the polymicrobial infections in the human airway.

• Journal of the Korean Home Economics Association
• /
• v.37 no.4
• /
• pp.29-40
• /
• 1999

Effects of the commercial laundry detergents, fabric softeners, and bleaches on bactericidal activities were studied. Bactericidal activities under various conditions during washing, rinsing, and bleaching were evaluated in terms of minimum inhibitory concentration(MIC) by a broth dilution method. The experiments were carried out using Staphylococcus aureus and Escherichia coli which were usually employed in antibacterial activity tests. The results are summarized as follows : 1. All samples of Powder detergents(10 samples), soaps(7 samples) and fabric softeners(4 samples) were inactive against the Staphylococcus aureus and Escherichia coli. 2. One sample in the liquid detergents(6 samples) showed a very low MIC for Staphylococcus aureus and Escherichia coli., and three samples showed a selective effect for two bacterial strains. 3. Bleaching agent(containing peroxide) did not have bactericidal effect for Staphylococcus aureus and Escherichia coli. but the other(containing chlorine) had the effect for every bacterial strain in standard concentration. 4. All samples showed bactericidal effect above 60$^{\circ}C$.

• Journal of Marine Bioscience and Biotechnology
• /
• v.9 no.2
• /
• pp.49-57
• /
• 2017

We isolated marine bacterium, isolate DG-2 which produces the antibiotics against MRSA (methicillin-resistant Staphylococcus aureus). This isolate DG-2 was examined by its morphological, biochemical properties, and 16S rRNA sequencing analysis. And then, isolate DG-2 was identified to the genus Streptomyces. Therefore, this isolate was designated as Streptomyces sp. DG-2. Streptomyces sp. DG-2 grew relatively well at $25^{\circ}C$, pH 7.0, and NaCl 1.0%. For the pre-purification of the bioactive compounds, DG-2 was fermented in 30 L PPES-II medium, and the culture filtrates of DG-2 was extracted by ethyl acetate. The ethyl acetate extract of DG-2 showed the significant anti-MRSA and antibacterial activities.

• Journal of Veterinary Clinics
• /
• v.34 no.3
• /
• pp.225-227
• /
• 2017

This study was investigated the zoonotic possibility of Staphylococcus schleiferi by adherence to both canine and human corneocytes. Staphylococcus pseudintermedius, Staphylococcus aureus, and S. schleiferi were prepared and canine and human corneocytes were collected via double-sided tape. Adhesion to human corneocytes was higher for S. schleiferi than S. pseudintermedius but highest for S. aureus. Regarding the canine corneocytes, S. schleiferi was the least adhesive strain. Furthermore, S. pseudintermedius adhered to the entire surface of both human and canine corneocytes. S. aureus and S. schleiferi, however, adhered to the corneocyte peripheries. Thus, S. schleiferi may have zoonotic potential and the potential is higher than S. pseudintermedius.

• Korean Journal of Microbiology
• /
• v.54 no.1
• /
• pp.77-78
• /
• 2018

Staphylococcus aureus is a Gram-positive and a round-shaped bacterium of Firmicutes phylum, and is a common cause of skin infections, respiratory infections, and food poisoning. Bacteriophages infecting S. aureus can be an effective treatment for S. aureus infections. Here, the draft genomic sequence is announced for a lytic bacteriophage SA7 infecting S. aureus isolates. The bacteriophage SA7 was isolated from a sewage water sample near a livestock farm in Chungcheongnam-do, South Korea. SA7 has a genome of 34,730 bp and 34.1% G + C content. The genome has 53 protein-coding genes, 23 of which have predicted functions from BLASTp analysis, leaving the others conserved proteins with unknown function.

• Journal of Food Hygiene and Safety
• /
• v.29 no.3
• /
• pp.223-227
• /
• 2014

This study was investigated to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) isolated from raw milk samples and to further study on the molecular characteristics of the MRSA isolates. Using Staphylococcus Medium 110, Staphylococcus spp. were isolated from raw milk samples and further identification was carried by Vitek2 system. Minimum inhibitory concentrations (MICs) of antibiotics were conducted by serial dilution method according to the Clinical Laboratory Standards Institute (CLSI) guideline. For the detection of resistance genes and molecular characterization, PCR reaction was performed by gene specific primers and followed by DNA sequencing. Of the 698 milk samples, 94 Staphylococcus aureus (S. aureus) were identified (94 S. aureus/286 Staphylococcus spp.). Of the 94 S. aureus, seven isolates have mecA, a methicillin resistant gene. mecA positive seven isolates were then characterized by staphylococcal cassette chromosome mec (SCCmec) typing, and Panton-Valentine Leukocidin (pvl) gene using PCR. All of mecA positive isolates were resistant to ampicillin and oxacillin, but sensitive to teicoplanin, vancomycin and ciprofloxacin. One of seven isolates was SCCmec type II and six isolates were type IV and all seven isolates were pvl gene negative.

• Korean Journal of Veterinary Service
• /
• v.23 no.4
• /
• pp.313-320
• /
• 2000

Staphylococcus aureus is a causative pathogen of bovine mastitis. It is recognized as a common pathogen in human and animal and specially enterotoxin-producing strain of S aureus is a common cause of staphylococcal food poisoning in human. Various food originated raw milk, cheese, butter produced from mastitic cow causes staphylococcal food poisoning. It is difficult to treat the staphylococcal mastitis because of increasing resistance by using overdose of antibiotics. This study was conducted to investigate the enterotoxin-production and coagulase serotypes of S aureus in Chonnam province for 6 month, 1999. Also we studied the antibiotic resistant pattern with 14 types against isolates. 18(10.1%) S aureus were isolated from 178 raw milk samples in seven farms. and 8 strains(38%) were isolated in 21 raw milk samples which was below 500,000 somatic cells. We identify that 7(87.5%) of 8 isolates and 15(83.3%) 18 isolates produce enterotoxin. Their enterotoxin serotype was type B(66.7%), type A(33.3%) and type C(13.3%). Also 2 strains of isolates was positive to the type A and B. Coagulase serotype of isolates was 2, 3, 4, 7, and 8. Most stains(70.6%) were serotype 2. And most strains(17 isolates, 94.4%) except one isolate was multiple resistant to the tested antibiotics.

• Korean Journal of Pharmacognosy
• /
• v.34 no.2 s.133
• /
• pp.142-144
• /
• 2003

Acetone extracts of 301 strains of marine-derived fungus were tested for antimicrobial activity against three strains of bacteria. The bacteria consisted of three pathogens, Staphylococcus aureus, methicillin-resistant S. Aureus, and multidrug-resistant S. aureus. The acetone extracts of 10 strains (MFA117, MFA130, MFA134, MFA206, MFA217, MFA268, MFA277, MFA291, MFA292, MFA301) showed strong activity, inhibiting 100% of the bacterial growth. These antimicrobial active strains were cultlued in SWS medium on a 1 L scale and the resulting broth and mycelium were extracted to afford mycelium extract (000M) and broth extract (000B), respectively. Antimicrobial activity for all extracts has been tested as the results, the mycelium extract of one strain (217M) and the broth extracts of 9 strains (117B,130B, 134B, 206B, 268B, 277B, 291B, 292B, 301B) exhibited relatively high levels of activity at minimal inhibitory concentration (MIC) values of $500-125\;{\mu}g/mL$ range. Among them, the extracts, 277B, 291B, 292B and 301B showed the most significant antimicrobial activity with $IC_{50}$ values of $125\;{\mu}g/mL$.