• Journal of Life Science
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• v.27 no.2
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• pp.202-210
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• 2017

As an effort to find a potential biopreservative, we isolated bacterial strains producing bacteriocin from fermented foods. A strain was finally selected and characteristics of the bacteriocin were investigated. The selected strain was identified as Bacillus subtilis E9-1 based on the 16S rRNA gene analysis. The culture supernatant of B. subtilis E9-1 showed antimicrobial activity against Gram-positive bacteria. Subtilisin A, ${\alpha}$-chymotrypsin, trypsin and proteinase K inactivated the antimicrobial activity, which means its proteinaceous nature, a bacteriocin. The bacteriocin activity was fully retained at the pH range from 2.0 to 8.0 and stable at up to $100^{\circ}C$ for 60 min. Solvents such as ethanol, isopropanol and methanol had no effect on the antimicrobial activity at the concentration of 100% but acetone and acetonitrile reduced the activity at up to 100% concentration. Cell growth of four indicator strains was dramatically decreased in dose-dependent manner. Listeria monocytogenes was the most sensitive, but Enterococcus faecium was the most resistant. Bacillus cereus and Staphylococcus aureus showed the medium sensitivity. The bacteriocin showed its antimicrobial activity against B. cereus and L. monocytogenes via bactericidal action. The number of viable cells of L. monocytogenes started to reduce after addition of bacteriocin to the minced beef. The bacteriocin was purified through acetone concentration, gel filtration chromatography and RP-HPLC. The whole purification step led to a 6.82 fold increase in the specific activity and 6% yield of bacteriocin activity. The molecular weight of the purified bacteriocin was determined to be 3.3 kDa by MALDI-TOF/TOF mass spectrometry.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.4
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• pp.514-528
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• 2014

This study examined the actual state and future improvement of food allergies in adolescents and adults in order to prevent damage. In this survey, proportions of females, people in their 40s, college graduates, and office workers and housewives with allergies were higher than other groups. Exactly 41.1% of participants responded that they had experienced food allergies while 58.9% responded that they had not. According to their responses, the most common food allergy symptom involved the skin while whole-body allergic reactions were rare. Most respondents answered that frequency of their food allergies was two or three times. There was a variety of allergenic foods, including fast food, eggs, mackerel and milk, and instant food was ranked as the most allergenic food. Therefore, in order to protect consumers from damage caused by food allergens, the food allergen labeling system must be improved. A better food allergen labeling system should be implemented to avoid potential risks of allergic reactions and ensure national food safety.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.355-363
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• 1982

In order to develop the commercial storage method of potatoes by irradiation combined with natural low temperature, storage room($450{\times}650{\times}250cm$; year round temperature change, $2-17^{\circ}C;\;70-85%\;R.H.$) on a batch scale followed by irradiation with optimum dose level. Irish cobbler and Shimabara were 100% sprouted after 3 months storage in control, whereas in 15 Krad irradiated group, sprouting was completely inhibited at Irish cobbler for 9 months storage, and at Shimabara for 12 months. The extent of loss due to rot attack after 9 months storage was 6% in control, 6-8% in 10-15 Krad irradiated group at Irish cobbler and weight loss was 16.5% in control, 5.1-5.6% in irradiated group, whereas rotting rate of Shimabara after 12 months storage was 100% in control, 15% in irradiated group and the weight loss of its was 12.6% in control, $7.3{\sim}7.4%$ in irradiated group. The moisture content in whole storage period of two varieties were $72{\sim}82%$ without remarkable changes. The total sugar and ascorbic acid contents were slightly decreased according to the dose increase and elapse of storage period, whereas reducing sugar content was increased. Irish cobbler was 90% marketable after 9 months storage and 85% in Shimabara after 12 months storage.

• Journal of Life Science
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• v.20 no.5
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• pp.710-716
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• 2010

This study was conducted to investigate the effect of Makgeolli (MG) and Makgeolli GiGemi (MGG) on blood flow, serum lipid improvement in vivo, and inhibition of angiotensin converting enzyme (ACE) in vitro. The activities of serum AST and ALT were increased by ovariectomy. Serum AST levels were decreased to $77.71{\pm}13.97$ and $74.57{\pm}14.90\;unit/ml$ in the OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($91.14{\pm}12.02\;unit/ml$). Serum ALT levels were decreased to $34.00{\pm}8.41$ and $30.43{\pm}3.60\;unit/ml$ in OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($37.14{\pm}5.40\;unit/ml$). Serum total cholesterol and triglyceride contents decreased in the sham group compared with OVX-control group by ovariectomy. Six weeks feeding of MG and MGG resulted in a decrease to $116.14{\pm}36.02$ and $109.14{\pm}11.55\;mg/dl$ compared to the OVX-control group ($120.43{\pm}8.36\;mg/dl$) in serum total cholesterol, and triglyceride levels were decreased to $52.43{\pm}12.41$ and $47.29{\pm}12.08\;mg/dl$ in the OVX-MG50 and OVX-MGG50 groups compared to the OVX-control group ($58.57{\pm}5.47\;mg/dl$). The level of HDL-cholesterol in the OVX-control group was significantly reduced to $51.29{\pm}20.49\;mg/dl$ compared to the sham group ($72.29{\pm}10.29\;mg/dl$), but it was increased to $70.71{\pm}19.53$ and $62.00{\pm}20.20\;mg/dl$ with MG and MGG supplementation. Furthermore, the effect of the MG group was higher than the MGG group. Microscopic observation showed that whole blood passed smoothly through the micro channels in the MG and MGG supplemented groups. The platelet aggregation ability of the groups treated with MG and MGG was less than that of the OVX-control group. In vitro assay, the angiotensin converting enzyme (ACE) activity was significantly inhibited by MG and MGG (82.6% and 68.9% inhibition at 0.4 g/ml). These results suggest that the beneficial effects of MG and MGG may be used to improve on the lipid metabolic syndrome of menopausal women. In addition, MG and MGG might improve blood homeostasis mediated activities via antiplatelets and MG and MGG may be used as antihypertensive functional foods and nutraceuticals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1544-1551
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• 2016

Various types of fermented soybean foods are consumed in various Asian countries, including China, Indonesia, Japan, Korea, and Vietnam. Cheonggukjang is a Korean whole soybean paste fermented by Bacillus subtilis and regarded as a healthy food. The objective of this study was to investigate the Ca-bioavailability and anti-osteoporotic effects of cheonggukjang (CGJ) containing high poly-gamma glutamate (PGA) contents in an animal model. Blood samples were collected from the jugular vein at 0, 0.5, 1, 2, 3, 4, and 5 h after a single oral dose in male rats. Ca-bioavailability in CGJ containing high PGA contents was approximately 3~5 times higher than that of natural CGJ. Female rats were either sham-operated (sham; n=5) or surgically ovariectomized (OVX; five animals per group) and then administered to OVX control, raloxifene hydrochloride (RLX) 1 mg/kg/d, or CGJ containing high contents of PGA (20 and 200 mg/kg/d) for 12 weeks. Serum osteocalcin concentration was significantly lower in the CGJ 200 mg/kg/d group compared with the OVX control group. Serum progesterone concentration was significantly higher in the CGJ 200 mg/kg/d group compared with the OVX control group. Reduction grade of the trabecular bone decreased in the RLX 1 and CGJ 200 mg/kg/d group compared with that of the OVX control group. In conclusion, CGJ 200 mg/kg/d may have inhibitory effects on osteoporosis in OVX rats, and Ca-bioavailability was improved in CGJ containing high PGA contents.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.1
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• pp.38-46
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• 2002

Chrysanthemum boreale M. (hereafter, C. boreale M.), a perennial flower, has been historically used as a natural medicine in Korea. With increasing concerns for health-improving foods, the demand for C. boreale M. has become higher than ever. Howevr, the amount of wild C. boreale M. collected from mountainous areas is not enough to cover all demands. The cultivation system and fertilization strategy are required to meet increasing demand on C. boreale M. with a good quality. We investigated the effects of nitrogen application on plant growth and effective components of C. boreale M. to suggest optimum rate of nitrogen fertilization. C. boreale M. was cultivated in a pot scale (1/2000a scale), and nitrogen applied with rate of 0(N0), 50(N50), 100(N100), 150(N150), 200(N200), and $250(N250)kg\;ha^{-1}$. Phosphate and potassium were applied at the same level ($P_2O_5-K_2O=80-80kg\;ha^{-1}$) in all treatments. Maximum yield achieved in 246 and $226kg\;ha^{-1}$ N treatment on the whole plant and the flower part, a valuable part as a herbal medicine, respectively. Proline was the most abundant amino acid in the flower of C boreal M. and the contents of amino acids increased with increasing nitrogen application rate in flower. Nitrogen recovery efficiency was high more than 41% in all nitrogen treatments and increased to 61.8% in nitrogen N100 treatment. From the nitrogen content, the high nitrogen uptake, the low residue of mineral N and the reasonably good apparent fertilizer recovery, it can be inferred that C. boreale M. made efficient use of the available nitrogen. In flower, contents of Cumambrin A. which is a sesquiterpene compound and has the effect of blood-pressure reduction, decreased with increasing nitrogen application. However, the amount of Cumambrin A in flower increased as nitrogen rate increased, because of increasing flower yield. Conclusively, nitrogen fertilization could increase yields and enhance quality. The optimum nitrogen application rate might be on the range of $225{\sim}250kg\;ha^{-1}$ in a mountainous soil.

• Journal of Korean Home Economics Education Association
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• v.19 no.4
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• pp.37-56
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• 2007

The purpose of this study is to provide basic resources to the first-grade Home Economics Regular Teacher Qualification Program (FGHERTQP) in order to improve its operation plans. For the study, the three methods were carried out: an analysis on the curricula of FGHERTQP over six years since 2000, a questionnaire asking their satisfaction degrees and needs on the programs which was answered by the home economics teachers who were the participants of FGHERTQP, and several statistical analyses such as a descriptive-test, a $X^2$-test, a t-test, and one way ANOVA by using SPSS Win ver 10.0. The results of the study were as follows; Firstly, FGHERTQP has been operated ten times by five training centers during resent six years. Subject matters ($1{\sim}7$), whole numbers of lectures ($11{\sim}29$), and their allotted working hours ($111{\sim}136$) vary with individual training centers and operation years. Secondly, when using 5 point likert scales, Contents and Methods of evaluation marked 3.08 which were the lowest scores, and Qualification Training in General marked 3.72 which was the highest score among five fields of Qualification Training in General, Contents, Organizations, Methods and Evaluation. The overall scores were low. Thirdly, in needs analysis on offering subject matters, the participants wanted to study the field of home economics education more than that of subject contents. Looking about the highest needs classified by domains, Food Principles & Meal Management showed the highest in Foods. And Consumer Issues in Clothing & Textiles in Textiles, Upcoming Housing Cultures in Housing, Family Relationship in Child Development & Family Relationship, Juveniles and their daily life as a consumer in Family & Consumer Resources Management. Fourthly, training centers' lectures available had a significant influence on the satisfaction degrees according to general characteristic variations of the participants. That is, as a training center offers more lectures in the field of subject education than those of subject contents, the participants showed higher satisfaction degrees (p<.05).