• Journal of Ginseng Research
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• 제44권2호
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• pp.194-204
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• 2020

The detrimental impact of air pollution as a result of frequent exposure to fine particles posed a global public health risk mainly to the pulmonary disorders in pediatric and geriatric population. Here, we reviewed the current literature regarding the role of ginseng and/or its components as antimicrobials, especially against pathogens that cause respiratory infections in animal and in vitro models. Some of the possible mechanisms for ginseng-mediated viral inhibition suggested are improvements in systemic and mucosa-specific antibody responses, serum hemagglutinin inhibition, lymphocyte proliferation, cell survival rate, and viral clearance in the lungs. In addition, ginseng reduces the expression levels of proinflammatory cytokines (IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-6, IL-8) and chemokines produced by airway epithelial cells and macrophages, thus preventing weight loss. In case of bacterial infections, ginseng acts by alleviating inflammatory cytokine production, increasing survival rates, and activating phagocytes and natural killer cells. In addition, ginseng inhibits biofilm formation and induces the dispersion and dissolution of mature biofilms. Most clinical trials revealed that ginseng, at various dosages, is a safe and effective method of seasonal prophylaxis, relieving the symptoms and reducing the risk and duration of colds and flu. Taken together, these findings support the efficacy of ginseng as a therapeutic and prophylactic agent for respiratory infections.

• Food Science and Biotechnology
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• 제18권3호
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• pp.636-640
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• 2009

The effect of post-cut vanillin treatment at high concentrations on changes of quality and microorganism in fresh-cut apples was studied. Apples (Malus domestica Borkh. cv. Fuji) were sliced, treated by dipping in different vanillin solution, 0, 40, 80, and 120 mM, packed in polyethylene bag, and then stored for up to 3 weeks at $4^{\circ}C$. Changes in total aerobic bacteria, yeast and molds, browning, soluble solids, and titratable acidity during storage were investigated. Growth of total aerobic bacteria throughout storage was strongly inhibited by vanillin regardless of treatment concentrations. Growth of yeast and molds was inhibited by vanillin of all concentrations until 2 weeks of storage. Levels of browning index, soluble solids, and titratable acidity were not significant difference among the treatment conditions until 2 weeks of storage. However, when stored for 3 weeks, browning index increased more at 80 or 120 mM vanillin, while soluble solids and titratable acidity more be decreased by 120 mM vanillin as compared with other treatment conditions. These results show that the usage of vanillin in processing of fresh-cut apples had a limitation for maintaining quality.

• Clinical and Experimental Pediatrics
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• 제62권6호
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• pp.199-205
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• 2019

Although Mycoplasma pneumoniae pneumonia (MPP) has been generally susceptible to macrolides, the emergence of macrolide-resistant MPP (MRMP) has made its treatment challenging. MRMP rapidly spread after the 2000s, especially in East Asia. MRMP is more common in children and adolescents than in adults, which is likely related to the frequent use of macrolides for treating M. pneumoniae infections in children. MRMP is unlikely to be related to clinical, laboratory, or radiological severity, although it likely prolongs the persistence of symptoms and the length of hospital stay. Thereby, it causes an increased burden of the disease and poor quality of life for the patient as well as a societal socioeconomic burden. To date, the only alternative treatments for MRMP are secondary antimicrobials such as tetracyclines (TCs) or fluoroquinolones (FQs) or systemic corticosteroids; however, the former are contraindicated in children because of concerns about potential adverse events (i.e., tooth discoloration or tendinopathy). A few guidelines recommended TCs or FQs as the second-line drug of choice for treating MRMP. However, there have been no evidence-based guidelines. Furthermore, safety issues have not yet been resolved. Therefore, this article aimed to review the benefits and risks of therapeutic alternatives for treating MRMP in children and review the recommendations of international or regional guidelines and specific considerations for their practical application.

• Obstetrics & gynecology science
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• 제61권6호
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• pp.688-692
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• 2018

Listeriosis is a rare foodborne infection caused by Listeria monocytogenes. It is 12-20 times more prevalent in pregnant women compared to the general population, with a 20-40% mortality rate in neonates. Early treatment with appropriate antimicrobial agents is critical for pregnancy outcomes; however, the infection is difficult to control because the nonspecific clinical manifestations and rarity of the disease often preclude early diagnosis. We encountered 2 cases of pregnancy-associated listeriosis that occurred at 29 and 37 weeks of gestation. Both neonates were delivered by emergent cesarean section due to fetal condition, and one of the preterm infants died immediately after birth. Pregnancy-associated listeriosis should be considered in the management of unexplained fever or inflammatory conditions in pregnant women.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.429-438
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• 2020

The emergence of multi-drug resistant, pathogenic methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health and has created a need for novel functional therapeutic agents. In this study, we evaluated the underlying mechanisms of the anti-MRSA effect of an azaphilone pigment, sclerotiorin (SCL) from Penicillium sclerotiorum. The antimicrobial activity of SCL was evaluated using agar disc diffusion, broth microdilution, time-kill assays and biophysical studies. SCL exhibits selective activity against Gram positive bacteria including MRSA (range, MIC = 128-1028 ㎍/ml) and exhibited rapid bactericidal action against MRSA with a > 4 log reduction in colony forming units within three hours of administration. Biophysical studies, using fluorescent probes and laser or electron microscopy, demonstrated a SCL dose-dependent alternation in membrane potential (62.6 ± 5.0.4% inhibition) and integrity (> 95 ± 2.3%), and the release of UV260 absorbing materials within 60 min (up to 3.2 fold increase, p < 0.01) of exposure. Further, SCL localized to the cytoplasm and hydrolyzed plasmid DNA. While in vitro checkerboard studies revealed that SCL potentiated the antimicrobial activity of topical antimicrobials such as polymixin, neomycin, and bacitracin (Fractional Inhibitory Concentration Index range, 0.26-0.37). Taken together these results suggest that SCL targets the membrane and DNA of MRSA to facilitate its anti-MRSA antimicrobial effect.

• 한국축산식품학회지
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• 제41권5호
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• pp.883-893
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• 2021

Clostridium difficile present in feces of food animals may contaminate their meats and act as a potential source of C. difficile infection (CDI) to humans. C. difficile resistance to antibiotics, its production of toxins and spores play major roles in the pathogenesis of CDI. This is the first study to evaluate C. difficile prevalence in retail raw animal meats, its antibiotics susceptibilities and toxigenic activities in Al-Jouf, Saudi Arabia. Totally, 240 meat samples were tested. C. difficile was identified by standard microbiological and biochemical methods. Vitek-2 compact system confirmed C. difficile isolates were 15/240 (6.3%). Toxins A/B were not detected by Xpect C. difficile toxin A/B tests. Although all isolates were susceptible to vancomycin and metronidazole, variable degrees of reduced susceptibilities to moxifloxacin, clindamycin or tetracycline antibiotics were detected by Epsilon tests. C. difficile strains with reduced susceptibility to antibiotics should be investigated. Variability between the worldwide reported C. difficile contamination levels could be due to absence of a gold standard procedure for its isolation. Establishment of a unified testing algorithm for C. difficile detection in food products is definitely essential to evaluate the inter-regional variation in its prevalence on national and international levels. Proper use of antimicrobials during animal husbandry is crucial to control the selective drug pressure on C. difficile strains associated with food animals. Investigating the protective or pathogenic potential of non-toxigenic C. difficile strains and the possibility of gene transfer from certain toxigenic/ antibiotics-resistant to non-toxigenic/antibiotics-sensitive strains, respectively, should be worthy of attention.

• 한국수산과학회지
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• 제55권6호
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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.

• 한국축산식품학회지
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• 제34권5호
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• pp.591-596
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• 2014

This study evaluated the effect of sodium diacetate and sodium lactate solutions for reducing the cell count of Pseudomonas spp. in frankfurters and hams. A mixture of Pseudomonas aeruginosa (NCCP10338, NCCP10250, and NCCP11229), and Pseudomonas fluorescens (KACC10323 and KACC10326) was inoculated on cooked frankfurters and ham. The inoculated samples were immersed into control (sterile distilled water), sodium diacetate (5 and 10%), sodium lactate (5 and 10%), 5% sodium diacetate + 5% sodium lactate, and 10% sodium diacetate + 10% sodium lactate for 0-10 min. Inoculated frankfurters and ham were also immersed into acidified (pH 3.0) solutions such as acidified sodium diacetate (5 and 10%), and acidified sodium lactate (5 and 10%) in addition to control (acidified distilled water) for 0-10 min. Total aerobic plate counts for Pseudomonas spp. were enumerated on Cetrimide agar. Significant reductions (ca. 2 Log CFU/g) in Pseudomonas spp. cells on frankfurters and ham were observed only for a combination treatment of 10% sodium lactate + 10% sodium diacetate. When the solutions were acidified to pH 3.0, the total reductions of Pseudomonas spp. were 1.5-4.0 Log CFU/g. The order of reduction amounts of Pseudomonas spp. cell counts was 10% sodium lactate > 5% sodium lactate ${\geq}$ 10% sodium diacetate > 5% sodium diacetate > control for frankfurters, and 10% sodium lactate > 5% sodium lactate > 10% sodium diacetate > 5% sodium diacetate > control for ham. The results suggest that using acidified food additive antimicrobials, as dipping solutions, should be useful in reducing Pseudomonas spp. on frankfurters and ham.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.151-159
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• 2016

Nanoparticles have wide-scale applications in various areas, including medicine, chemistry, electronics, and energy generation. Several physical, biological, and chemical methods have been used for synthesis of silver nanoparticles. Green synthesis of silver nanoparticles using plants provide advantages over other methods as it is easy, efficient, and eco-friendly. Nanoparticles have been extensively studied as potential antimicrobials to target pathogenic and multidrug-resistant microorganisms. Their applications recently extended to development of antivirals to inhibit viral infections. In this study, we synthesized silver nanoparticles using Cinnamomum cassia (Cinnamon) and evaluated their activity against highly pathogenic avian influenza virus subtype H7N3. The synthesized nanoparticles were characterized using UVVis absorption spectroscopy, scanning electron microscopy, and Fourier transform infrared spectroscopy. Cinnamon bark extract and its nanoparticles were tested against H7N3 influenza A virus in Vero cells and the viability of cells was determined by tetrazolium dye (MTT) assay. The silver nanoparticles derived from Cinnamon extract enhanced the antiviral activity and were found to be effective in both treatments, when incubated with the virus prior to infection and introduced to cells after infection. In order to establish the safety profile, Cinnamon and its corresponding nanoparticles were tested for their cytotoxic effects in Vero cells. The tested concentrations of extract and nanoparticles (up to 500 μg/ml) were found non-toxic to Vero cells. The biosynthesized nanoparticles may, hence, be a promising approach to provide treatment against influenza virus infections.

• Journal of Periodontal and Implant Science
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• 제45권6호
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• pp.223-228
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• 2015

Purpose: The goal of this study was to characterize the patterns of antimicrobial resistance and virulence genes in samples of Staphylococcus aureus (S. aureus) isolated from periodontitis patients. Methods: From July 2015 to August 2015, oral saliva was collected from a total of 112 patients diagnosed with periodontitis, including 80 outpatients in dental hospitals and 32 patients in dental clinics located in Seoul and Cheonan. The samples were subjected to a susceptibility test to evaluate the prevalence of antimicrobial resistance, and the pathogenic factors and antimicrobial resistance factors in the DNA of S. aureus were analyzed using polymerase chain reaction. Results: A susceptibility test against 15 antimicrobial agents showed that 88% of cultures were resistant to ampicillin, 88% to penicillin, and 2% to oxacillin. Resistance to at least two drugs was observed in 90% of cultures, and the most common pattern of multidrug resistance was to ampicillin and penicillin. Enterotoxins were detected in 65.9% of samples. The cell hemolysin gene hld was detected in 100% of cultures and hla was detected in 97.6% of samples. All strains resistant to penicillin and ampicillin had the blaZ gene. The aph(3')IIIa gene, which encodes an aminoglycoside modifying enzyme, was detected in 46.3% of samples. Conclusions: In the treatment of oral S. aureus infections, it is important to identify the pathogenic genes and the extent of antimicrobial resistance. Furthermore, it is necessary to study patterns of antimicrobial resistance and cross-infection in the context of periodontological specialties in which antimicrobials are frequently used, such as maxillofacial surgery, where the frequency of antimicrobial use for minor procedures such as implant placement is increasing.