• Journal of agriculture & life science
• /
• v.50 no.3
• /
• pp.119-127
• /
• 2016

The current disinfection method of vehicles being applied in South Korea has various shortcomings. So, the epidemic has generated continuously at livestock farms. It is very important to develop an effective disinfection system for reduction of the epidemic. And various basic data is required for this development. Therefore, this study was performed to identify the nozzle type and proper discharge pressure of sprayers. The experiment was conducted from January 10, 2012 until February 28, 2012. All the performance measurement experiments were repeated five times. The subjects of experiment were the A, B and C company's products. The sprayed capacity, angle of spray and the covering area ratio were measured for each product. As a result, the sprayed capacity, angle of spray and the covering area ratio were increased as the discharge pressure of the sprayer was increased. In conclusion, the conical shaped of the nozzle is considered more appropriate than V-shaped, and the proper discharge pressure is expected to be at least 20kg/㎠.

• Journal of Life Science
• /
• v.12 no.6
• /
• pp.796-802
• /
• 2002

The purpose of this study was to determine changes in their insluin and leptin in 30 obese girls' high school students, 26kg/$m^2$ or over in BMI after the aerobic exercise and obese education program over 8 weeks and then those changes 8 weeks after the program. Those 30 obese students were divided into four groups, aerobir exercise and obese education(8), aerobic exercise(8), obese education(8) and control group(6). Aerobic exercise was applied in the form of jogging for 8 weeks, 4 times a week and 50 minutes a time and with the exercise strength of 65 to 75% HRmax. Obese education was provided 60 minutes per week over the same weeks. The results of the study can be described as follows. 1) For the level of insulin, aerobic exercise and obese education, and aerobic exercise groups showed a more significant decrease after the programs were completed than either before they were applied or 8 weeks after they were halted(p＜.05). 2) In terms of the level of leptin, aerobic exercise and obese education, and aerobic groups accomplished a more significant lowering after the programs were completed than either before they were started or 8 weeks after they were stopped(p＜.05).

• Microbiology and Biotechnology Letters
• /
• v.2 no.1
• /
• pp.1-7
• /
• 1974

For the purpose of producing cellulosic single-cell protein from the agricultural wastes, 172 strains of cellulose-assimilating bacteria were isolated from 102 samples of rotten woods, compost soils, soils and so on by the enrichment culture technique. The isolates were examined for their ability to utilize cellulose as carbon source, and then six strains were screened by their strong cellulose assimilating ability and identified as follows: 1. Among six strains of bacteria screened, five strains were identified as species belonged to the genus Cellulomonas and the remainder to the genus of Sporocytophaga. 2. The isolated Sporocytophaga species was identified as S. ellipsosporn because it has a ellipsoidal microcyst. 3. The isolated Cellulomonas species were identical to a strain of C. fimi, C. aurcgena, C. gelida, respectively and two strains to C. flavigena. 4. The isolated C. aurogena was proved to be a new variety becauuse it has different characteristics of assimilating pentoses such as arabinose and xylose from the strain discribed in Bergey's Manual.

• Microbiology and Biotechnology Letters
• /
• v.36 no.4
• /
• pp.320-325
• /
• 2008

Some anti-dementia, cardiovascular and antioxidant functionalities of Korean traditional alcoholic beverages were characterized. Anti-dementia acetylcholinesterase inhibitory activities were generally not detected or low except BHS-ju (19.5%) and buthyrylcholinesterase inhibitory activities were also show below 1.0%. However, $\beta$-Secretase inhibitory activities were high in PMR-ju (42.5%), WJY-ju (41.6%) and SSJ-ju (42.9%). Antihypertensive angiotensin I-converting enzyme inhibitory activities was the highest in YON-ju (85.6%), however fibrinolytic activities were not detected in all traditional alcohol beverages. Furthermore, antioxidant activities were very high in SBB-ju (72.2%) and GMB-ju (67.9%), however SOD like activities generally were show below 20%.

• Journal of Life Science
• /
• v.19 no.12
• /
• pp.1705-1711
• /
• 2009

Carcinoma cells that had acquired resistance to a chemotherapeutic drug often show cross-resistance to various other cytotoxic drugs. In the present study, we explored the effect of heat shock in cisplatin-resistant gastric cancer cells SNU601/Cis2 to figure out the efficacy of hyperthermia in drug-resistant carcinoma. While SNU601/WT cells showed a high-sensitivity response to heat shock by dying through apoptosis, SNU601/Cis2 cells were considerably resistant to mild heat shock, but died by necrosis upon treatment with harsh heat shock. The occurrence of necrosis in SNU601/Cis2 cells was linked to the suppression of both JNK1/2 activation and HSP27 induction in response to heat shock. Since necrosis is closely associated with tumor malignancy and poor prognosis through inflammatory responses, our result suggests that hyperthermic treatment should be carefully applied when it is combined with chemotherapy.

• Journal of Life Science
• /
• v.15 no.2 s.69
• /
• pp.202-210
• /
• 2005

Following ingestion, Salmonella must adhere to and colonize the intestinal epithelium of the host in order to establish infection. S. typhimurium synthesize several appendages that are believed to mediate attachment. These include type 1 fimbriae, plasmid-encoded (PE) fimbriae, long polar (LP) fimbriae, and thin aggregative fimbriae. However, the precise roles of these putative adhesins remain unclear, due to conflicting data in the literature. We constructed strains lacking four different fimbriae including type 1 fimbriae, PE fimbriae, LP fimbriae, and thin aggregative fimbriae, as well as strains lacking each fimbriae alone. In cell culture adhesion assays, these mutants adhered to several mammalian cell lines as well as wild-type S. typhimurium. These strains were also screened for virulence in mice, and all strains were virulent or nearly as virulent as their wild-type parents. In contrast, When a strain lacking four fimbriae was screened for virulence in chicks, it was found to be highly attenuated. This suggests a role for either type 1 fimbriae, PE fimbriae, LP fimbriae or thin aggregative fimbriae or a combination of thease fimbriae in the colonization of chicks. It also suggests that differences exist with respect to the surface structures that mediate attachment of Salmonella in chicks as compared with mice.

• Journal of Life Science
• /
• v.14 no.1
• /
• pp.115-120
• /
• 2004

Lepista nuda is a world-wide species which has and international reputation as a excellent edible species. In this study, we investigated the genetic variation and taxonomic relationship of L. nuda and other five Tricholomataceae species were analyzed by random amplied polymorphic DNA (RAPD). 15 kinds of random primers were used. The distance matrix was calculated using UPGMA and phyolgenetic relationship were inferred by neighnor-joining (NJ) method. Various bands of 100bp∼1600bp were observed in electrophoretic patterns of RAPD. Nei's genetic distance was calculated using a total of 228 DNA bands identified, and phylogenetic tree was made. The Nei's genetic variations of L. nuda, Lepista surdida, Collybia peronata, Collybia confluens, Lyophyllum cinerascens, Laccara laccata were 0∼21.3%, 21.2∼28.0%, 15.4∼23.0%, 14∼21.8%, 16.5∼34.6%, and 12.4∼27.4%, respectively The consistency index, the retention index and homoplasy index were 0.5217, 0.5769 and 0.5156, respectively. Also, two groups could be made by NJ tree. The genetic distance between L. nuda and C. confluens was closer than that between L. nuda and L. sordida.

• Journal of Life Science
• /
• v.20 no.6
• /
• pp.964-967
• /
• 2010

Plasmid-mediated quinolone resistance (PMQR) determinants have been contributed to quinolone resistance of gram-negative bacteria worldwide. However, little data on the prevalence of these determinants in bacteria from animals are available in Korea. In this study, the prevalence of PMQR genes was investigated with E. coli originating from diseased animals. Among 55 E. coli tested, 11 showed PMQR genes by PCR. The most prevalent genotype was qepA (14.5%), followed by aac(6')-Ib-cr (7.3%) and qnrS (1.8%). Interestingly, two isolates with PMQR genes did not show quinolone resistance in this study. The isolates exhibited higher fluoroquinolone resistance in aac(6')-Ib-cr in combination with qnrS or qepA compared with aac(6')-Ib-cr only. In a conjugal transfer test, PMQR genes were transferred from donor to recipient.

• Microbiology and Biotechnology Letters
• /
• v.42 no.3
• /
• pp.211-218
• /
• 2014

In order to isolate probiotic lactic acid bacteria possessing high inhibitory activities against porcine and zoonotic pathogens, such as enterotoxigenic E. coli, Salmonella Typhimurium, and Clostridium perfringens, a total of 65 anaerobic strains were initially isolated from a variety of sources including cattle rumen fluids, chicken intestines and swine feces. Four Bifidobacterium strains were selected for their high anti-pathogenic bacterial activities. By using the 16S rDNA sequencing method, three B. boum strains and one B. thermophilum were identified. B. thermophilum demonstrated the best adhesive ability to epithelial cells of swine intestine among the isolates. Indeed, B. thermophilum was seen to have superior characteristics as a probiotic for swine, as judged by their high growth inhibitory activities against various pathogens, and high acid- and bile-tolerance.

• Microbiology and Biotechnology Letters
• /
• v.16 no.5
• /
• pp.413-420
• /
• 1988

The strain capable of growing on minimal medium containing aniline as a sole source of carbon was isolated from activated sludges and identified as Pseudomonas putida biotype A. The characterizations of the strain were determined. The optimum concentration for growth of the strain was 1-20 mM of aniline. No changes of pH were detected during cultivation. Some metabolic products of biodegradation of aniline were detected after cultivation of the strain on 10 mM aniline for 48 hours. The strain showed to be resistant to streptomycin, tetracycline, trimethoprim, and sulfanilamide. The strain was also capable of utilizing other aromatic compounds related to aniline as a sole source of carbon. One plasmid carried by this strain was detected. The properties of some of the mutant strains treated with mitomycin C were also discussed. The results suggest that separate, regulatory enzyme systems capable of degrading aniline may exist in plasmid DNA.