• Journal of Microbiology and Biotechnology
• /
• 제25권5호
• /
• pp.709-717
• /
• 2015

Airborne bacteria from hog farms may have detrimental impacts on human health, particularly in terms of antibiotic resistance and pathogen zoonosis. Despite human health risks, very little is known about the composition and diversity of airborne bacteria from hog farms and hog-related spray fields. We used pyrosequencing analysis of 16S rRNA genes to compare airborne bacterial communities in a North Carolina hog farm and lagoon spray field. In addition, we isolated and identified antibiotic-resistant bacteria from both air samples. Based on 16S rRNA gene pyrosequence analysis, Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria were the dominant phyla in airborne bacterial communities from both hog farm and spray field sites. Within the Firmicutes genera, Clostridium spp. were more abundant in the hog farm, whereas Staphylococcus spp. were higher in the spray field. The presence of opportunitic pathogens, including several Staphylococcus species and Propionibacterium acnes, was detected in both bioaerosol communities based on phylogenetic analysis. The isolation and identification of antibiotic-resistant bacteria from air samples also showed similar results with dominance of Actinobacteria and Proteobacteria in both hog farm and spray field air. Thus, the existence of opportunistic pathogens and antibiotic resistant bacteria in airborne communities evidences potential health risks to farmers and other residents from swine bioaerosol exposure.

• 한국식품과학회지
• /
• 제52권3호
• /
• pp.296-303
• /
• 2020

Hop-resistant lactic acid bacteria (LAB) are well-known, major beer-spoilage bacteria. The hop-gradient agar containing ethanol (c-HGA+E) method has been used to examine hop-resistance of beer-spoilage LAB. However, the selection of beer-spoilage bacteria by the c-HGA+E method is either too selective or too inclusive. Furthermore, it is accompanied by a complicated experimental procedure, high-cost and time. To overcome these disadvantages, the modified hop-gradient agar with ethanol (m-HGA+E) method was developed. The most remarkable modifications were the shape of the petri dish and the inoculation method for bacteria. The efficiency and validation of the m-HGA+E approach were proven by the formation of colonies at different hop concentrations in the bottom layer, co-culture with the bacteriocin producer and by PCR detection of hop-resistant genes. This study demonstrated that m-HGA+E is a rapid, economical, and easy method to monitor potential hop-resistant beer-spoilage LAB during the beer brewing process.

• 한국환경보건학회지
• /
• 제19권2호
• /
• pp.10-15
• /
• 1993

Hygienic condition of farm waters has an effect on the hygiene of dairy foods. So we examined Standard Plate Count, coliform, E. coli, heat-resistant bacteria, psychrophilic bacteria, Pseudomonas aeruginosa and enterococcus for the bacterial sanitation of 78 farm waters in Kyunggi Province. Of the 78 farm waters, the average number of psychrophilic bacteria was 750 $\pm$ 170/ml, SPC 440 $\pm$ 130/ml, Pseudomonas aeruginosa 130 $\pm$ 97/100/ml, Coliform 22 $\pm$ 17/ml, E. coli 10 $\pm$ 6/100/ml, Heatresistant bacteria 5 $\pm$ 1ml, and Enterococcus 2 $\pm$ 1/100/ml. The percent of over than 1000/ml in SPC and psychrophilic bacteria of 78 farm water was 11.5% and 23.1%, respectively. The rate of over than 10/ml in coliform and heat-resistant bacteria was 12.8% and 15.4%, respectively and the rate of over than 10/100 ml in E. coli, Pseudomonas aeruginosa and enterococcus was 8.9%, 33.3%, and 2.6%, respectively. Pseudomonas aeruginosa was no significant between any other indicator organisms, and psychrophilic bacteria was significant with only SPC but other indicator organisms were highly significant with each other.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
• /
• 제30권2호
• /
• pp.15-22
• /
• 2024

Purpose: In general, cross-infection caused by bacteria occurs more in hospitals than in local communities. In most cases, infectious diseases spread through contact transmission (direct contact, indirect contact). This study tries to examine which places are most likely to detect infections bacteria and what materials should be used to effectively suppress the spread of infectious bacteria. Methods: Domestic and international literature have been reviewed to determine which bacteria are common and spread in which places. At the same time, antibacterial experiments for several finishing materials are performed to determine the survival period of bacteria for each material. The experiment is conducted mainly on antibiotic-resistant bacteria (MRSA, CRE, etc.) that have a high mortality rate and are very contagious. Results: MRSA has a high incidence in many hospital departments with surgery or immunocompromised patients, such as the elderly, organ transplant patients, and hemodialysis patients. There are experimental results that MRSA dies early in ceramics or silk wallpaper. CRE has a high incidence in hospital departments where there are many patients who are prone to bacteria entering the body directly, such as ventilator patients or critically ill patients with surgical wounds. There are experimental results that CRE dies early in silk wallpaper. In addition, bacteria die on the surface for a variety of reasons. Most MRSA and CRE develop in patients with impaired immunity or surgery, and rapidly die in copper or materials with antibacterial properties. Implications: If finishing materials surface with the ability to kill specific bacteria is used in the place where a large number of specific bacteria are detected, the spread of infectious diseases can be effectively controlled.

• 한국환경농학회지
• /
• 제33권4호
• /
• pp.409-413
• /
• 2014

BACKGROUND: Large amount of veterinary antibiotics have been used in the livestock industry to prevent diseases and promote growth. These antibiotics are excreted through feces and urine in unchanged form and reach to agricultural fields via application of the livestock manure based composts. The purpose of this study was to evaluate the occurrence of tetracyclines-resistant bacteria in the soil received livestock manure compost for a long term. METHODS AND RESULTS: Tetracyclines (tetracycline TC, chlortetracycline CTC, and oxytetracycline OTC) resistance bacteria in the soil of rice-onion field applied pig manure compost (PM), in the soil of grass-rye field received cow manure compost (CM), and in the soil of rice field applied inorganic fertilizer (NPK) were determined. The soil received livestock manure composts clearly showed higher number of TC, CTC, and OTC resistance bacteria compared with the soil treated with inorganic fertilizer. The antibiotic resistant bacteria recovered appeared at 80 mg/L of tetracyclines was identified 1 specie, 6 genera 7 species, and 6 genera 7species in the soils received CM, PM, and NPK, respectively. The dominant resistant bacteria with the CM and PM application were Ochrobactrum and Rhodococcus. CONCLUSION: The application of livestock manure compost in the agricultural field is likely to contribute the occurrence of antibiotic resistance bacteria in the agricultural environment.

• 한국자기공명학회논문지
• /
• 제6권1호
• /
• pp.69-77
• /
• 2002

During the screening of material which has the antimicrobial activity against aminoglycoside-resistant bacteria, A new material $\varepsilon$-(L-$\beta$-Iysine) polypeptide from a culture medium of Streptomyces sp.(DWGS2) was isolated, and the structure and the physicochemical properties of the new material were elucidated. The new material was separated by column chromatography of the culture medium using Dowex1$\times$2, Silica gel, and Sephadex LH20 etc. The chemical structure and molecular weight were determined with the data of various NMR experiments, MALDI mass, and ESI mass experiments. The antimicrobial activity of $\varepsilon$-(L-$\beta$-Iysine) polypeptide is not only better than equal to the activity of known aminoglycoside type of antibiotics(MIC=3.125 - 6.25ug/mL) but also effective against aminoglycoside-resistant bacteria and fungi. If the mechanism of antimicrobial activity against aminoglycoside- resistant bacteria is figured out, the $\varepsilon$-(L-$\beta$-Iysine) polypeptide can be utilized for the treatment of diseases caused by aminoglycoside-resistant bacteria.

• 한국수산과학회지
• /
• 제51권4호
• /
• pp.397-403
• /
• 2018

We determined the resistance rates of pathogenic bacteria isolated from cultured olive flounder Paralichthys olivaceus to erythromycin (Em), antibiotic typically used in aquaculture and analyzed the genotypes of resistant bacteria using polymerase chain reaction (PCR). We isolated and utilized 160 isolates of Streptococcus parauberis, 1 of S. iniae, 66 of Edwardsiella tarda, 56 of Vibrio sp. and 23 of unidentified bacteria from presumed infected olive flounder from Jeju Island from March 2016 to October 2017. Of the 306 isolated strains, Em-resistant strains included 33 of S. parauberis, 39 of E. tarda and 2 of Vibrio sp. We conducted PCR to assess the resistance determination of Em-resistant strains. Five different types of Em-resistance genes were detected in the 74 Em-resistant strains: erm (A), erm (B), erm (C), mef (A) and mef (E); erm (A) and erm (B) were detected in 1 (3%) and 24 (72.7%) S. parauberis isolates, respectively. In E. tarda, erm (B) was detected in five isolates (12.8 %) and no Em-resistance genes were detected in the two Vibrio sp. isolates.

• 한국의상디자인학회지
• /
• 제24권3호
• /
• pp.63-71
• /
• 2022

This paper aims to compare and verify the antibacterial effects of cotton fabrics naturally dyed with extracts of Ulmus davidiana var. japonica Nakai, Caesalpinia sappan, Saururus chinensis, and Artemisia princeps against antibiotic-resistant strains of bacteria. After natural dyeing of the test fabric, Al, Cu, Fe mordants were used. The color fastness against washing, rubbing, and perspiration of the cotton fabrics dyed with the 4 types of extracts were mostly excellent. However, the color fastness against light showed poor results for all four types. As for the antibacterial test method, MRSA (ATCC 33591) was applied to the cotton fabrics dyed with the four kinds of extracts and cultured for 24 hours. After that, the bacteria that proliferated on the fabrics were collected and spread on a solid medium. The bacteria were measured to find out the bacteriostatic reduction rate for the antibiotic-resistant strains. As a result of the analysis, all four extracts showed a high bacteriostatic reduction rate of more than 99% when the copper mordant was used. Even with the lack of a mordant, the bacteriostatic reduction rate was high, at 99.9% for Caesalpinia sappan and 94.6% for Saururus chinensis.

• 한국식품영양학회지
• /
• 제24권4호
• /
• pp.708-712
• /
• 2011

This study was focused on the determination of antibacterial activity of $Scutellaria$ $baicalensis$ extract against antibiotic resistant bacteria($Salmonella$ Enteritidis, $Staphylococcus$ $aureus$ and enteroaggregative $E.$ $coli$). Extract of $Scutellaria$ $baicalensis$ were tested for antibacterial activity by paper disc methods. The $Scutellaria$ $baicalensis$ extract in 0.1 g/$m{\ell}$ and 0.2 g/$m{\ell}$ showed a significant antibacterial activity against antibiotic resistant bacteria. Minimum inhibitory concentration (MIC) of $Scutellaria$ $baicalensis$ extract were appeared to 2,048 ${\mu}g/m{\ell}$ at $S.$ Enteritidis, $S.$ $aureus$ and enteroaggregative $E.$ $coli$. Finally, the growth incubation curve was determined using $Scutellaria$ $baicalensis$ extract against $S.$ Enteritidis, $S.$ $aureus$ and enteroaggregative $E.$ $coli$. The growth of $S.$ Enteritidis was significantly inhibited within 10 hours by the addition of at least 10,000 ppm of $Scutellaria$ $baicalensis$ extract. The 10,000 ppm of $Scutellaria$ $baicalensis$ extract retarded the growth of $S.$ $aureus$ and enteroaggregative $E.$ $coli$ more than 10 hours. In conclusion, $Scutellaria$ $baicalensis$ extract might be useful to control antibiotic resistant bacteria $in$ $vitro$.

• 환경생물
• /
• 제29권4호
• /
• pp.286-295
• /
• 2011

Bacteria resistant to various antibiotics have recently become an issue of the utmost importance. Resistant strains are not uncommon, even in municipal drinking water sources. The health threat posed by resistant, pathogenic bacteria has serious ramifications for both public health and agriculture. In this study, we isolated antibiotic resistant bacteria from water samples from the Han River, Korea, which is contaminated by the wastewater from many industrial complexes, hospitals, agricultural and animal husbandry estates, and from wastewater treatment facilities. We determined the degrees of resistance to various antibiotics exhibited by the isolated strains. The similarities between the isolated $E.$ $coli$ strains were examined, using the pulsed field gel electrophoresis and multilocus sequence typing, in order to trace their origins and to explore the syntechnic adaptations and pathogenicity of the various strains and relate these to their genetic sequence. A total of 25 $E.$ $coli$ strains were isolated from six stations along the Han River. All the 25 strains exhibited resistance to ampicillin. We also investigated resistance to amoxicillin, clavulanic acid, cefazolin, cofoxitin, cefotaxime, cefpodoxime, ceftriaxone, cefepime, nalidixic acid, aztreonam, ciprofloxacin, streptomycin, gentamicin, chloramphenicol and imipenem. Based on the ESBL detection, 14 strains belonged to the ESBL producing strains. The number of the clonal complex producing strains was 5 among the 14 isolated strains. The 5 strains were included in the 168, 23, 38, 469, 156 clonal complex, respectively. The rest 9 strains were not included in the clonal complex, but showed independent STs.