• Korean Journal of Microbiology
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• v.42 no.2
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• pp.142-148
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• 2006

In order to develop chitosanase for the production of chitosan oligosaccharides, a chitosanase-producing bacterium was isolated from the traditional fermented soybean, Meju, and identified as Bacillus amyloliquefaciene MJ-1. The cloned chitosanase gene, 825 bp in size, encoded a single peptide of 274 amino acids with a estimated molecular mass of 30.9 kDa. The deduced amino acid sequence showed significant homology with microbial chitosanases. The recombinant chitosanase was expressed in Escherichia coli upon induction with isopropyl-D-thiogalactopyranoside, and purified using $Ni^{2+}-NTA$ agarose column chromatography. The maximal activity of the recombinant chitosanase is at pH 5.0 and $60^{\circ}C$. The recombinant chitosanase is stable between pH 5.0 and pH 7.0 at $37^{\circ}C$ for 30 min, and more than 75% of the activity still remain at $80^{\circ}C$ for 30 min incubation.

• Research in Plant Disease
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• v.12 no.2
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• pp.108-114
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• 2006

This study was conducted to elucidate the interactions among soil microorganisms in a special field where one, two or three of N, P, K fertilizers were continuously not applied for 29 years. Crop yield (barley, soybean), soil chemical properties and microflora and microfauna including nematodes, nematophagous fungi, actinomycetes, bacteria, and fungi were examined for two years. Tylenchorhynchus sp. was the most important plant-parasitic nematode (range $11{\sim}642/300 cm^3$ soil) followed by Pratylenchus sp. and Helicotylenchus sp. Among nematophagous fungi, Monacrosporium spp. was the most frequently found followed by Harposporium sp. and Cystopage sp. In general, plots treated with phosphate fertilizer yielded more, had more nematodes, bacteria and actinomycetes. In contrast, total fungal population densities including nematophagous fungi, Cystopage sp. and Harposporium sp. were in reverse; they were more abundant in the plots with lower phosphate contents. Phosphate and pH are positively correlated and two most important determining factors for the population density of soil organisms under investigation. According to correlation analysis, Ca, Mg, and $SiO_2$ contents in soil and population densities of Tylenchorhynchus sp., saprophitic nematodes, actinomycetes, and bacteria were positively correlated with pH, but were negatively correlated with fungal population densities. We hope that the study will add an additional knowledges to understand our mysterious underworld.

• Journal of Preventive Medicine and Public Health
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• v.35 no.4
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• pp.295-304
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• 2002

Objectives : This study was carried out to investigate the cause, magnitude and transmission route of the cholera outbreak in 2001 Methods : The study population were those persons who ingested foods at the restaurant, were confirmed as cholera patients, had symptoms of diarrhea and sewed as workers at the restaurant. A questionnaire survey and microbiological examinations on the microbes isolated from rectal swabs were conducted. Of the cases, 316 food histories were surveyed by an analysis of the restaurant menu. Results : There were 139 confirmed cases of cholera reported in Korea in 2001. Of these, 104 were related to the restaurant. By region, Gyeongsangbuk-do had the highest incidence with 91 cases. Of these 91 cases, 74 had ingested foods at the restaurant, 2 were employees and 3 were secondary infection cases within the families. The results of the odds ratio analysis of the 316 persons having ingested foods at the restaurant were as follows: sandwiches 5.07 (95% CI, 1.85-14.59), soybean curd 2.45 (95% CI, 1.09-5.56), noodles 2.34 (95% CI, 1.24-4.42), steamed squid 2.01 (95% CI, 1.17-3.47) and vinegared rice 1.82 (95%, CI, 1.08-3.09). It was certain the restaurant in question was the cause of the 2001 outbreak. Conclusions : We suspected that more than one restaurant employee contaminated foods served at the restaurant. In addition, eating raw fishes purchased at the Pohang Fisheries infected the employees of the restaurant. There is a possibility that these raw fishes were themselves contaminated by cholera bacilli in the sea.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.209-219
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• 2010

This study was carried out to evaluate the effects of applying levels of organic liquid fertilizer (OLF) on growth and fruit quality of hot pepper. The OLF was made with compositions of chicken dung : rice bran : soybean meal (2:1:1). Hot pepper was applied with 5 treatments; control (chemical fertilize), OLF-1.0X (standard applying levels), OLF-0.7X (70% of standard applying level), and OLF-1.3X (130% of standard applying level). The plant height was reduced at 23cm in the OLF-1.0X treatment compared to control of 293cm. The number of hot pepper fruits was significantly increased. The content of capsaicin in the ripened pepper decreased by 23.6% in the OLF-1.0X treatment with $253mg{\cdot}kg^{-1}$ compared with control of $331mg{\cdot}kg^{-1}$, but the content of free sugar increased by 19.5%. The content of capsaicin and soluble solid content in OLF-1.3X treatment were significant different with other treatments. The yield of red pepper in OLF-1.0X treatments increased by 15% with $4,190kg{\cdot}10a^{-1}$ compared to control of $3,643kg{\cdot}10a^{-1}$, and OLF-1.3X and OLF-0.7X treatments showed increase by 10% and 6%, respectively.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.141-149
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• 2018

This experiment was conducted to investigate the effects of multi-enzyme on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.1% multi-enzyme (Multi; mixture of ${\beta}-mannanase$, xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Measurements were growth performance, morphology of ileum, apparent ileal digestibility and apparent total tract digestibility of dry matter, crude protein, and energy of weaned pigs. There were no significant differences on growth performance during overall experimental period. No differences were found for the morphology of ileum and nutrient digestibility between CON and Multi groups. Therefore, the results in the current study indicated that multi-enzyme supplementation in diets had no effects on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.151-161
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• 2018

This study was designed to investigate the effects of multi-enzyme on diarrhea and immune responses of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.1% multienzyme (Multi; mixture of ${\beta}-mannanase$, xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Frequency of diarrhea, levels of packed cell volume (PCV), white blood cells (WBC), immunoglobulins, cortisol, tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), transforming growth $factor-{\beta}$ ($TGF-{\beta}$), and C-reactive protein (CRP) were measured. Multi group tended to decrease (p<0.1) diarrhea frequency than CON group during 2 wk after weaning. Lower values of PCV on d 3 (p<0.05) and d 7 (p<0.1) were found in Multi group compared with CON group. There were no significant differences on WBC number and immunoglobulin (Ig) M and A between Multi and CON groups. However, Multi group tended to increase (p<0.1) Ig G on d 7 than CON group. Moreover, Multi group showed modulated immune responses, indicated by decreased levels of cortisol (p<0.05) on d 7 and 14, $TNF-{\alpha}$ on d 3 (p<0.05) and d 7 (p<0.10), $TGF-{\beta}$ on d 2 (p<0.05) and d 7 (p<0.10), and CRP (p<0.10) on d 3 and 7 after weaning compared with CON group. Consequently, inclusion of multi-enzyme in diets for weaned pigs improved gut health and modulated immune responses of weaned pigs.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.652-655
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• 2013

Natural habitats of weedy melons were distributed on the islands along and on the west and south coasts of Korean peninsula including Boryeong, Seosan (Taean), Seocheon, Okgu, Buan, Gochang, Yeonggwang, Muan, Shinan, Haenam, Jindo, Wando, Goheung, Yeocheon, Hadong, Namhae, Goseong, Tongyeong, Geoje, and Jeju islands including Jeju city, Bukjeju-gun and Nam Jeju-gun. Weedy melons were found growing wildly in or around the cultivated lands in these regions. Natural habitats of weedy melons were in and around the cultivated lands. Weedy melon plants were found most often in soybean fields, followed by fields of mungbean, sweet potato, pepper, sesame, cotton, and peanuts. The plants were also found growing wild in foxtail millet fields, rice paddy levees along the streams, upland field edges, watermelon fields, corn fields, vegetable gardens near farmhouse, orange fields, compost piles, fallow fields, roadside and home gardens. They inhabited in sunny and a little dry spaces in relatively low-height crop plant fields in general. The time of fruit maturity was from early July to late October with the most frequency in September according to post survey answer. Fruits dropped off from the fruit stalk when matured. This phenomenon was thought beneficial for perpetuation in the wild. The fruits were being used commonly for food and toys for children. It was thought that weedy melons were perpetuating through the cycle of human and animal feeding of the fruits, human and animal droppings, often mixed in compost, and application of the compost to crop fields by human.

• Korean Journal of Food Science and Technology
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• v.6 no.4
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• pp.193-198
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• 1974

The antioxidant activity of ground red pepper, ethyl alcohol extracts of ground red pepper peel and alcohol extracts plus organic acid was studied by using edible soybean oil as a substrate. All the substrates were stored in a dark place at $45.0{\pm}0.5^{\circ}C$ respectively. The results of the study were as follow: 1. Ground red pepper, black pepper and cassia exhibited slight antioxidant activity and there was no significant difference in antioxidant activity among them. 2. Although both ground red pepper peel and red pepper seed showed antioxidant activity, ground red pepper peel exhibited greater antioxidant activity than ground red pepper peel did. 3. Ethyl alcohol extracts of red pepper peel showed strong antioxidant activity, but the residue did not show the antioxidant activity. 4. The antioxidant activity of the ethyl alcohol extracts of red pepper peel increased in direct proportion to the concentration of the extracts. 5. In connection with the synergistic effect of organic acid to the ethyl alcohol extracts of red pepper peel, citric acid showed a very strong synergistic effect on the antioxidant activity of red pepper, while ascorbic acid showed a weak effect. On the other hand, phosphoric acid showed an accelerating effect on the oxidation of oils. 6. The maximum antioxidant activity of the ethyl alcohol of ground red pepper peel was observed at the citric acid concentration of 0.04%, when tested at various concentration of citric acid.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.2
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• pp.104-108
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• 2016

The objective of this study was to determine how feeding forage and concentrate separately (SF) or as a total mixed ration (TMR) affects enteric methane production of cattle. Six Holstein steers ($203{\pm}22.5kg$) were used in a $2{\times}3$ changeover design experiment. Experimental diets (TMR and SF) consisted of compound feed, timothy hay and soybean curd residue in a ratio of 40:48:12, respectively, and diets were fed at 10% of metabolic body weight, on an as-fed basis. There were no differences in dry matter intake and enteric methane production (g/d) between SF and TMR but the methane conversion rate (methane energy/GE intake) of TMR was significantly higher (p=0.05) than that of SF. The mean methane emission factor (kg/head/year) and conversion rate of the two treatments were 21.4 and 0.05, respectively. There was a strong relationship between metabolic body weight and enteric methane production (p<0.001). At the present time, further studies may be necessary in order to establish the effects of TMR and SF on enteric methane production.

• Korean Journal of Food Science and Technology
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• v.52 no.2
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• pp.125-129
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• 2020

In this study we developed a method for determining the geographic origin of soybeans by combining energy dispersive X-ray fluorescence spectrometry with statistical analysis. In 2018, 197 soybean samples (100 Korean domestic samples and 97 foreign samples) were collected for the construction of a geographic origin model. The mineral concentrations of 26 elements were measured and determined via the fundamental parameters approach. One-way analysis of variance, t-test, and canonical discriminant analysis were employed to reveal five elements (P, Ni, Br, Zn, and Mn) that could be used for the determination of geographic origins. The sensitivity, specificity, and efficiency for the above method were 91.0, 95.9, and 93.4%, respectively. Validation results from 60 samples collected in 2019 showed a predictive rate of 93.3% for Korean domestic soybeans and 100.0% for foreign soybeans. In conclusion, the combination of energy dispersive X-ray fluorescence spectrometry and chemometrics could be used to effectively determine the geographic origin of soybeans.