• Food Science and Biotechnology
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• v.15 no.1
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• pp.24-27
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• 2006

A simple HPLC quantification method was developed for genistein, genistin, daidzein, and daidzin in soybeans and soybean products. The procedure used a $4.6{\times}100\;mm$ $Chromolith^{(R)}$ RP-18e column with a mobile phase of 1% HOAc in 20% MeOH to 1% HOAc in 80% MeOH for 10 min. The injection volume was $2\;{\mu}L$ at a flow rate of 2 mL/min. Detection was carried out under UV at 254 nm. Under these conditions, the major isoflavones daidzein, daidzin, genistein, and genistin in soybean and soybean pastes were eluted within 7 min with baseline separation. Optimal extraction of the above four major isoflavones was achieved when 40 g of soybean or soybean paste was refluxed in 100 mL of 95% ethanol for 2 hr. Ten different soybean cultivars and nine commercial soybean pastes were analyzed by this method. The total isoflavone content was highest in the cultivar Somyung ($2,497\;{\mu}g/g$ dry weight). The isoflavone content in soybean pastes varied widely from manufacturer to manufacturer (an almost five-fold difference between the highest and lowest values). Such variations were presumably due to differences in fermentation conditions, type of soybeans used, and levels of such additives as starch and salt.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2207-2212
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• 2013

Cancer prevention is rapidly emerging as a major strategy to reduce cancer mortality. In the field of breast cancer, significant strides have recently been made in the understanding of underlying preventive mechanisms. Currently, three major strategies have been linked to an increase in breast cancer risk: obesity, lack of physical exercise, and high levels of saturated dietary fat. As a result, prevention strategies for breast cancer are usually centered on these lifestyle factors. Unfortunately, there remains controversy regarding epidemiological studies that seek to determine the benefit of these lifestyle changes. We have identified crucial mechanisms that may help clarify these conflicting studies. For example, recent reports with olive oil have demonstrated that it may influence crucial transcription factors and reduce breast tumor aggressiveness by targeting HER2. Similarly, physical exercise reduces sex hormone levels, which may help protect against breast cancer. Obesity promotes tumor cell growth and cell survival through upregulation of leptin and insulin-like growth factors. This review seeks to discuss these underlying mechanisms, and more behind the three major prevention strategies, as a means of understanding how breast cancer can be prevented.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.397-401
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• 1997

The present research program was conducted to characterize a strain of actinomycetes producing an anti methicillin-resistant Staphylococcus aureus (MRSA) antibiotic. Soil samples were collected from various sites in Korea and a number of actinomycetes were isolated from the soil samples by applying selective agar for actinomycetes. Among over 400 isolates, a strain (AMLK-135) producing anti-MRSA antibiotic against S. aureus TK 784 was selected. According to the morphological and physiological characteristics, the strain AMLK-135 was confirmed to belong to the genus Streptomyces. From the results of species identification with the TAXON program, the strain AMLK-135 was shown to belong to major cluster 5 (Streptomyces exfoliatus), but it had a low simple matching coefficient ($S_{SM}$ SM/) value to member organisms of major cluster 5. Percentage ($\%$) of strain further away of the strain AMLK-135 was low (1.9400) and it was placed further away than the outer-most members in major cluster 5. Therefore, the strain AMLK-135 was identified as a new species of the genus Streptomyces.

• Journal of The Korean Association For Science Education
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• v.13 no.2
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• pp.219-229
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• 1993

The purpose of this study is to investigate college science students' and science teachers' understanding of chromosomal behavior in the context of cell division. The research problems were as follows: 1. What is the level of college science students' understandings of chromosomal behaviors? 2. What is the level of science teachers' understandings of chromosomal behaviors? 3. What is the level of understanding by grade and major area? The sample consisted of 28 sophomore, 17 junior and 23 senior biology students; and 23 middle school science teachers and 14 high school biology teachers. The instrument of the study was a short answer required paper and pencil test. The results of the study were as follows: 1) About 15 percent of the sample could not count the number of chromosome in a cell in appropriate. 2) Seventy percent of the students, and 80 percent of the teachers identified homologous chromosomes as ones with the similar shape and size, and 30 percent of the whole sample could not pair two homologous chromosomes. 3) About 70 percent of the students and 30 percent of the teachers could not mark corresponding allele on chromosome. 4) Biology major students showed higher understanding of overall chromosomal behaviors than non Biology students. Based upon the results, some implications were made. The major one was a development of a teaching model in which students can improve the ability to connect chromosome theory to mendelian genetics.

• Korean Journal of Veterinary Research
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• v.46 no.1
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• pp.13-19
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• 2006

Generally known psittacosis or ornithosis is a disease of birds caused by the bacterium Chlamydia psittaci. Humans are accidential hosts and are most commonly infected from avian sources. It raises hepatitis or neurosis. As major outer membrane protein (MOMP) of Chlamydia psittaci has been known to play a role in the avoidance of host immune defenses, research on developing a Chlamydia vaccine has focused on the MOMP. In this study, the gene encoding the major outer membrane protein (MOMP) of the Chlamydia psittaci strain 6BC was cloned and expressed in Escherichia coli strain M-15. The recombinant DNA was cloned by fusion prokaryotic expression vector pQE30-GFPII. Expression of the recombinant protein was performed in E. coli and was induced by IPTG. The size of expressed recombinant protein is 74.220 kDa (MOMP, 43.260 kDa; GFP expression region, 30 kDa; $6{\times}His$ tag, 960Da). This protein was purified by using his-tagging-inclusion body. Recombinant protein was reconfirmed through ELISA test and western blot with antibody against pQE30-GFPII. It will be useful antibody development.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.2
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• pp.29-37
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• 2011

Commercially managed bees are available for pollination services and are used in large commercial fields, small gardens, or enclosures such as greenhouses and screen houses. This paper describes the current status and agricultural utilization of commercially managed bumblebees as well as bumblebee rearing techniques in Korea. We surveyed the use rate and number of bumblebees for the pollination of 10 major horticultural crops and fruit trees in Korea; in 2009, the use rates were approximately 7.9% and 2.8%, respectively. The use number of bumblebees as pollinators was more than 64,345 colonies, which included 51,400 colonies for 10 major horticultural crops and 12,945 colonies for 10 major fruit trees in 2009. The value of bumblebees as pollinators in 2009 in Korea was estimated at more than 5,100,000,000 won. We also describe feeding, rearing room conditions, colony initiation, mating and diapause breaks to establish year-round mass rearing techniques of the bumblebee Bombus ignitus.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.97.1-97.1
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• 2006

• Proceedings of the Zoological Society Korea Conference
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• 2000.10a
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• pp.216.2-217
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• 2000

No Abstract, See Full Text

• BMB Reports
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• v.29 no.4
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• pp.343-352
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• 1996

The biosynthesis of phospholipid and the composition of fatty acid were analyzed in mitochondria isolated from Chlorella ellipsoidea treated with carbon sources (glucose, sucrose, raffinose) during the culture. The growth of Chlorella and total lipid contents in mitochondria treated with various carbon sources was increased to compare with the control. When Chlorella mitochondria was treated with various carbon sources, four kinds of phospholipid were increased predominantly. The major fatty acids utilized for the biosynthesis of the phospholipid were analyzed linoleic acid (average 25.18%) and stearic acid (average 10.52%) in the control. But, it was shown that the major fatty acids in Chlorella mitochondria treated with glucose were stearic acid (average 30.93%), palmitic acid (average 17.47%) and stearic acid (average 20.31%), linoleic acid (average 16.68%) in sucrose treatment and oleic acid (average 17.17%), palmitic acid (average 15.64%) in raffinose treatment.

• Journal of Life Science
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• v.13 no.5
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• pp.732-739
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• 2003

The purpose of this study was to determine if the addition of spermatozoa into the culture medium could influence the nuclear maturation of denuded porcine germinal vesicle (GV) oocytes in vitro. Cumulus-oocyte complexes were collected from follicles of 3 to 5 mm in diameter, The cumulus and corona cells were removed from oocytes. Porcine denuded oocytes were cultured in tissue culture medium containing spermatozoa. After 48 h culture, oocytes were examined for the evidence of GV breakdown, metaphase I, anaphase-telophase I, and metaphase II (M II). The proportion of oocytes reaching M II stage was significantly (P<0.01) increased in the oocytes cultured in media containing spermatozoa compared to those in media without spermatozoa $(31.9\pm1.8%\; vs\; 14.9\pm1.0%)$.No differences in the rates of M II were observed among the different period of spermatozoa exposure nor among the spermatozoa from different species. The proportion of oocytes reaching M II stage was significantly different between high and low concentrations of spermatozoa. The present study suggests that mammalian spermatozoa contain a substance(s) that improves nuclear maturation in vitro of GV oocytes. Enhancing effect of spermatozoa for oocytes maturation in vitro is a highly dose-dependent.