• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.458-463
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• 2022

We evaluated the antibiotic susceptibilities, hemolytic activities, and technological properties of 36 Staphylococcus xylosus strains and 49 S. pseudoxylosus strains predominantly isolated from fermented soybean foods from Korea. Most of the strains were sensitive to chloramphenicol, erythromycin, gentamycin, kanamycin, lincomycin, oxacillin, tetracycline, and trimethoprim. However, 23 strains exhibited potential phenotypic acquired resistance to erythromycin, lincomycin, and tetracycline. Based on breakpoint values for staphylococci from the Clinical and Laboratory Standards Institute, >30% of the isolates were resistant to ampicillin and penicillin G, but the population distributions in minimum inhibitory concentration tests were clearly different from those expected for acquired resistance. None of the strains exhibited clear α- or β-hemolytic activity. S. xylosus and S. pseudoxylosus exhibited salt tolerance on agar medium containing 20% and 22% (w/v) NaCl, respectively. S. xylosus and S. pseudoxylosus strains possessed protease and lipase activities, which were affected by the NaCl concentration. Protease activity of S. pseudoxylosus was strain-specific, but lipase activity might be a characteristic of both species. This study confirms the potential of both species for use in high-salt soybean fermentation, but the safety and technological properties of strains must be determined to select suitable starter candidates.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.918-926
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• 2021

We isolated 28 Vibrio vulnificus strains from seawater and fisheries and investigated the positive rate of eight virulence genes. Additionally, we evaluated the susceptibility of these strains to 25 antimicrobials. The positive rates of fur, vvhA, tcp, rtxA, vcgC, viuB, vvp, and acfA were 100, 92.9, 92.9, 67.9, 64.3, 25.0, 14.3, and 7.1%, respectively. A disk diffusion susceptibility test revealed that, all the investigated strains had the highest resistance to amoxicillin and oxacillin, followed by that to streptomycin (96.4%), cefoxitin (92.9%), clindamycin (82.1%), amikacin (67.9%), vancomycin (46.4%), nalidixic acid (7.1%), penicillin G (7.1%), and ampicillin (3.6%). Moreover, they were susceptible to 10 other antimicrobials, including cefotaxime, chloramphenicol, erythromycin, gentamicin, and rifampicin. Notably, amoxicillin, oxacillin, and streptomycin had average minimum inhibitory concentrations of 132.6, 603.4, and 23.1 ㎍/mL against V. vulnificus, respectively. These observations provide new insights regarding the necessity for sanitation of commercial fisheries and can potentially, help reduce the risk posed by fisheries contaminated with bacteria resistant to antimicrobials.

• Journal of Marine Bioscience and Biotechnology
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• v.14 no.2
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• pp.143-154
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• 2022

We isolated marine actinomycetes, strain D-5 which produces anti-methicillin resistant Staphylococcus aureus (anti-MRSA) compound. Streptomyces sp. D-5 relatively grew well in the 20~25℃, pH 8.0, and NaCl 3.0%. The ethyl acetate extract of D-5 culture was separated by C₁₈ ODS open column and reverse phase HPLC to yield anti-MRSA compound. The molecular weight of this compound was determined to be 898 by a Liquid chromatograph-mass spectrometer (LC-MS). Compared with penicillin G, this compound showed significant anti-MRSA activity. It also exhibited an inhibition zone of 26 mm at a concentration of 64 ㎍/disk and an inhibition zone of 16 mm at a concentration of 16 ㎍/disk against the MRSA KCCM 40511. Furthermore, the co-treatment of HPLC peak 5 compound and vancomycin caused a more rapid decrease in MRSA cells than each compound alone. It showed 86.8% growth inhibition activity within 12 hours at a low concentration of 50 ㎍/mL during co-treatment, and 97.1% growth in-hibition activity within 48 hours against MRSA KCCM 40511. Taken together, our results suggest that Streptomyces sp. D-5 and its anti-MRSA compound could be employed as a potent agent in MRSA infection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.6
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• pp.850-857
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• 2022

Seventy-five Vibrio parahaemolyticus isolates from the surface seawater of the Geum River Estuary area, on the west coast of Korea, were analyzed for the presence of virulence genes and susceptibility to 17 different antimicrobials. All 75 isolates were examined for the presence of two virulence genes (tdh or trh) using polymerase chain reaction; Only one of the isolates possessed the tdh or trh gene. According to the results of disk diffusion susceptibility tests, all of the strains were resistant to penicillin G, 92.0% were resistant to ampicillin, 82.7% were resistant to amoxicillin, 2.7% were resistant to ciprofloxacin, 2.7% were resistant to trimethoprim, 1.3% were resistant to cephalothin, and 1.3% were resistant to erythromycin. However, all of the strains were susceptible to amikacin, cefoxitin, chloramphenicol, gentamycin, kanamycin, nalidixic acid, nitrofurantoin, rifampin, streptomycin, and tetracycline. The average minimum inhibitory concentrations for ampicillin for V. parahaemolyticus was 557.6 ㎍/mL. These results not only provide novel insight into the necessity for seawater sanitation in Geum river estuary area, but they help reduce the risk of contamination of antimicrobial-resistant bacteria.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.420-429
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• 2000

Oral & maxillofacial infections are most commonly odontogenic in origin. Although such infections are usually self-limiting, they may occasionally spread deeply into fascial spaces or planes far from the initial site of involvement. If early diagnosis and appropriate therapy is delayed, complications such as mediastinal extension, retropharyngeal spread and airway obstruction could happen to the patients. For the study of the microbiology, we have retrospectively analysed the oral & maxillofacial infected patients in the Dept. of Oral & Maxillofacial Surgery. In-Ha University Hospital from 1997 September to 2000 April. The results were as follows 1. The male patients were more common than female, with male 61.9% and female 38.1%. 2. Dental originated infections were most common cause with the incidence of 62%. 3. Most common fascial space involved was buccal space 42cases(37.2%) followed by submandibular space 13cases(11.5%), infraorbital space 13cases(11.5%), masseteric space 11cases(9.7%), periapical abscess 11cases(9.7%). 4. The causative organisms isolated from the pus culture were Gram Positive Bacterial species, which were 46cases(31.9%) of Streptococcus viridans, 16cases(8.6%) of ${\alpha}$ and ${\beta}-hemolytic$ streptococcus, 4cases(3.1%) of Strep.-group D non enterococci, 7cases(5.1%) of Staphylococcus Coa. neg., 5cases(3.9%) of Staphylococcus aureus, 3cases(2.3%) of Enterococcus faecalis, 1case(0.8%) of Bacillus species, 1case(0.8%) of Peptostreptococcus, 1case(0.8%) of Clostridium and Gram negative bacterial species, which were 4cases(3.1%) of Acinetobacter baumannii, 2cases(1.6%) of Pseudomonas aeruginosa, 2cases(1.6%) of Burkholderia cepacia, 1case(0.8%) of Neisseria species, 1case(0.8%) of Klebsiella pneumoniae, 1case(0.8%) of Klebsiella oxytoca, 1case(0.8%) of Escherichia coli. 5. In drug sensitivity test, high resistant tendency was found in Penicillin system(Penicillin G 83.3%, Ampicillin 60%) and Aminoglycosides (Gentamycin 50%, Tobramycin 45.5%), but tertiary Cephalosporin system(Cefoperazone 9.1%, Ceftazidime 18.2%), and glycopeptides system (Teicoplanin 0%, Vancomycin 0%) showed lower resistancy.

• Journal of Life Science
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• v.14 no.4
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• pp.664-669
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• 2004

The contamination of Bacillus cereus was investigated in 240 RTE (ready-to-eat) food samples including 118 seafoods, 82 Korean packaged meals and 40 other RTE foods. Many B. cereus presumptive strains were isolated from the enrichment culture in Tryptic Soy Broth (TSB) added polymyxin, followed by selective culture in Mannitol Egg Yolk Polymyxin (MYP) agar and Gram staining. A total of 36 strains (16 in seafoods, 17 in Korean pack-aged meals and 3 in other RTE foods) were identified as B. cereus by the analysis of 61 biochemical tests of the API 50CHB/20E system test and supplementary tests of $\beta$-hemolysis, rhizoid growth, motility and oxidase activity. The 28 strains out of 36 B. cereus isolates produced diarrhoeal enter-otoxin in Brain Heart Infusion (BHI) broth. All isolates were resistant to ampicillin and penicillin antibiotics, and most of them were susceptible to gentamicin, vancomycin, bacitracin, chloram-phenicol, kanamycin and streptomycin. The growth of B. cereus was affected by environmental temperature and incubation time. Culture with temperature under 1$0^{\circ}C$ effectively restricted the growth of B. cereus.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.133-138
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• 2013

In this study, a total of 256 samples of retail raw meats (beef, pork and chicken) and sashimi were investigated for the presence of Enterococcus faecalis and Enterococcus faecium. We isolated a total of 117 E. faecalis and E. faecium from the samples, with contamination rates ranging from 18.8% for sashimi samples to 68.8% of chicken samples. E. faecalis was the predominant species recovered from all of the retail raw meats beef (42.2%), pork (42.2%), chicken (65.6%) and sashimi (12.5%). Among 117 isolates, 61 isolates (52.1%) were resistant to tetracycline, 32 isolates (27.4%) were resistant to erythromycin, 23 isolates (19.7%) were resistant to chloramphenicol, 16 isolates (13.7%) were resistant to ripampin, 10 isolates (8.5%) were resistant to gentamycin, 9 isolates (7.7%) were resistant to ciprofloxacin and 1 isolate (0.9%) was resistant to ampicillin and penicillin G. No resistance to amoxicillin + clavulanic acid and vancomycin was observed. Although no strain was resistant to vancomycin, the vanB gene was observed in 9 of 117 of Enterococcus (7.7%) demonstrating potential risk of vancomycin-resistant Enterococcus (VRE). Our results indicate that E. faecalis and E. faecium were highly prevalent in retail raw meats, but most strains were sensitive to tested antibiotics.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.279-289
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• 1995

The most important object of periodontal treatment is the perfect regeneration of destructed periodontal tissue. The healing of periodontal lesion is affected by several cells & factors, which result in formation of long juntional epithelium, root resorption, bony ankylosis or connective tissue attachment. And ideal healing is enhanced by epithilial exclusion or periodontal ligament cell activation. In this investigation, I studied the effect of Zizyphus Fructus extract which enhances biologic activity& collagen synthesis, on the chemotaxis & cell nature. The cells were obtained from interdental area & middle third area of the freshly extracted teeth for the orthodontic purpose. And they were fully incubated in${\alpha}-MEM$ solution containing $100{\mu]g/ml$ penicillin & $100{\mu]g/ml$ streptomycin followed by 6 generation incubation. The test cells were collected by trypsin-EDTA & centrifuge in the fully incubated cells, counted by Hernacyotmeter, incbated $5{\times}10^5/ml$ cells for 24 hours, re-incubated 24 hours in media containing natural extract and photographed. The cells were incubated for 4 hours in 48 well microchemotaxis chamber bisecting upper & lower chamber by 8ug/m pore polycarbonate membrane coating 5mg/ml gelatin solution. The migrated cells in microscope were counted, which meaned cell chemotaxis activity. The study had shown that the morphology of cell was spindle-shaped as the control group, and the subextract test groups were not significantly different. In gingival fibroblasts, the chemotaxis effect of PDGF was statistically significant compared to control group. The Zizyphus Fructus extract was more or less enhanced chemotaxis effect and in $1{\mu}g/ml$ concentration the chemotaxis effect was slightly elevated compared with $10{\mu}g/ml$ concentration. But, among the subextracts, it was not significantly defferent. In PDL cells, the chemotaxis effect of PDGF in statistically significant, and the zizyphus Fructus extract had shown the enhanced effect. The effect was slightly higher in $1{\mu}g/ml$ concentration than 10g/ml concentration,and no significance among the subextracts.

• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.291-310
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• 1998

This study was performed to evaluate the effects of extracts of Drynariae Rhizoma on the characteristics of rat calvaria cells(RCV) and bone marrow cells(RBM) which have the important role on the bone formation in vitro. Drynariae Rhizoma has been known as the useful herbal medicament for treatment of the wound healing including regeneration of bone fracture, and also has been used to treat the periodontal lesions, tooth mobility, gingival bleeding and pus discharge via sulcus in Oriental Medicine. In control group, the cells were cultured alone with Dulbeco's Modified Eagle's Medium contained with 10% fetal bovine serum, 100U/ml penicillin, $100{\mu}g/ml$ streptomycin, $0.5{\mu}g/ml$ amphotericin-B. In experimental group, extracts of Drynariae Rhizoma(0.1, 1, 5, 10, $50{\mu}g/ml$) were added into the above culture condition. And then each group was characterized by examing the cell proliferation at 1, 3, 7, 14, 21, 30th day, the amount of total protein synthesis and alkaline phosphatase activity of RCV at 2,4th day and those of RBM at 3, 6th day. And also, the calcified nodule of RCV was examed at 3, 5th day in three goup, control, experimental, culture with the PDGF group. The results were as follow ; 1. Both RCV and RBM cells in Drynariae Rhizoma-treated experimental group proliferated more rapidly than nontreated control group. The experimental group below $5{\mu}g/ml$ Drynariae Rhizoma-treated showed more prominent cell proliferation from the 7th day to the 21st day than the control group and above $10\;{\mu}g/ml$ treated group in RCV. 2. Amount of total protein synthesis was more increased in Drynariae Rhizomatreated group than in control group. In $5{\mu}g/ml$ Drynariae Rhizoma-treated group showed most prominent protein synthesis of the any other exrperimental group and control group. 3. Alkaline phosphatase activity also more increased in Drynariae Rhizomatreated group than control group. 4. Mineralized nodules in Drynariae Rhizoma-treated group were more than not in control group but also in PDGF-treated group. From the above results, Drynariae Rhizoma appeared to enhanced the proliferation, protein synthesis, alkaline phosphatase activity and cellular ability of mineralized nodule formation than PDGF. So that, we conclude that Drynariae Rhizoma enhances the activities of bone cells which have the important role on the periodontal regeneration and optimal application of Drynariae Rhizoma was thought to be useful as the means in bone regeneration.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.1
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• pp.57-63
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• 2019

This study was conducted to find out the effect that ${\kappa}-Carrageenan$ has on the properties of dog sperm when it was added to the cryoprotectant. Extender basically was contained 1.21 g Trizma base, 0.67 g citric acid, 0.4 g glucose, 0.03 g penicillin G, 0.05 g streptomycin sulfate. Extender1 was added with 0.1%, 0.2%, 0.3%, and 0.5% carrageenan, while extender2 was supplemented with glycerol. After freezing-thawing, the motility, viability, acrosome integrity, apoptosis, and ROS (reactive oxygen specifications) of sperm were measured to analyze the effects of the supplementation of carrageenan. Total Motile (TM), Rapid Progressive Motile (RPM), Medium Progressive Motile (MPM), and Immotile were measured through the CASA system after thawing in 37 degree water. Extender with 0.2% ${\kappa}-carrageenan$ ($64.26{\pm}0.49$) was significantly higher than control ($40.24{\pm}8.27$) (p < 0.05). RPMs of extender with 0.1%, 0.2% ${\kappa}-carrageenan$ ($57.64{\pm}6.34$, $56.47{\pm}1.35$) were significantly higher than the other groups (p < 0.05). Acrosome integrity was measured by dyeing to PSA-FITC with an epifluorescence microscope. Normal acrosome ratio of extender with 0.5% ${\kappa}-carrageenan$ ($61{\pm}8.03$) was higher than the other groups (p < 0.05). Apoptosis was measured with a FACSCalibur flow cytometer using FITC (FITC Annexin V Apoptosis Detection Kit). Treated groups of ${\kappa}-carrageenan$ of 0.1% ($0.81{\pm}0.05$), 0.2% ($0.85{\pm}0.05$) were significantly higer (p < 0.05) than control. Modified SYBR/PI staining was used for determination of viability and DCF staining was used for evaluation of ROS. Viability and ROS were not significantly different from other groups. In conclusion, adding a certain concentration of carrageenan to the extender of cryopreservation, carrageenan contributes to the improvement of the sperm motility, acrosome integrity and prevention of apoptosis.