• Journal of Plant Biology
• /
• v.32 no.4
• /
• pp.247-253
• /
• 1989

Protoplasts were enzymatically isolated from suspension culture of sweet potato. High yields of single protoplasts were produced from nonembryogenic cell aggregates. However, most protoplasts obtained from embryogenic cell clumps were spontaneously fused during enzyme treatment; a small portion of them remained single. Upon transfer to Murashige and Skoog's(MS) liquid medium supplemented with 0.1 mg/1 6-benzyladenine(BA) and 1 mg/12,4-dichlorophenoxyacetic acid(2,4-D), protoplasts from nonembryogenic cell aggregates sustained cell divisions to form cellus. Upon subculture onto MS media with 0.2 mg/12,4-D or without growth regulators, the callus did not give rise to any organs. On the other hand, first cell division of single protoplasts from embryogenic cell clumps was sporadically observed.

• Journal of Plant Biotechnology
• /
• v.49 no.3
• /
• pp.213-221
• /
• 2022

Wild garlic (Allium victorialis var. platyphyllum, AVVP) is a nontimber forest product used as an edible and medicinal vegetable. AVVP is usually propagated form offspring bulbs but it takes a long time to harvest. Using tissue culture technology could overcome this problem. This study investigated the optimal conditions for shoot multiplication, root growth, and plant growth by scooping AVVP bulbs. AVVP bulbs harvested from Ulleung Island, Korea, the main producer of AVVP, were surface-sterilized and used for in vitro propagation. Shoot multiplication was performed by the scooping method. More than five multiple shoots were induced from scooped tissue in Quoirin and Lepoivre (QL) medium containing plant growth regulators (PGRs); the maximum number of multiple shoots were induced from scooped tissue in QL medium containing 0.45 μM thidiazuron (TDZ) after 16 weeks of culture. Roots were induced directly at the base of the shoots in all treatments. In vitro rooting depended on the type of PGRs, and the best root-inducing treatment was QL medium containing 9.84 μM indole-3-butyric acid (IBA). Plants with in vitro roots were transferred to pots containing artificial soil and successfully acclimatized for 4 weeks. The acclimatized plants showed a survival rate of 80% after 20 weeks and gradually promoted growth depending on the acclimatization period. The results of this study will be of great help to AVVP dissemination through sustainable mass propagation.

• Journal of the Korean Dietetic Association
• /
• v.19 no.3
• /
• pp.209-222
• /
• 2013

This study examined the hygiene practices of contract foodservice employees and investigated the influence of education and work environment on these hygienes practices. A questionnaire was distributed to 250 contract foodservice employees and a total of 232 responses were received and analyzed. The overall score for hygiene practices of contract foodservice employees was 3.89 based on a 5-point scale. Cross-contamination was prominent (highest score at 4.46) and the heating temperature was less prominent (lowest score at 3.49). The factors most affecting contract foodservice employees were their work period, the size of the contract foodservice management company, the number of meals served daily, the frequency of meal service per day and the frequency of hygiene education. Compared to small and medium-sized contract foodservice management companies, the major contract foodservice management companies showed higher scores for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection (P<0.01), and personal hygiene (P<0.05). The frequency of hygiene education had a significant effect on the performance levels for refrigerator/freezer control (P<0.001), vegetable/fruit disinfection (P<0.001), thawing (P<0.001), heating temperature (P<0.001), cleaning/disinfection control (P<0.001), food supply control (P<0.05), and personal hygiene (P<0.05). From these results, to increase the sanitation quality of contract foodservice operations, hygiene practice levels need to increase and hygiene education systematically should be enforced for foodservice employees.

• The Korean Journal of Food And Nutrition
• /
• v.28 no.5
• /
• pp.782-793
• /
• 2015

The purpose of this study is the examination of stress levels and the eating habits that are affected by stress, and the provision of basic nutritional education data for the improvement of the eating habits of students who have experienced stress-related nutritional problems. Using the BEPSI-K instruments, a questionnaire survey was administered to 327 student subjects (166 male and 161 female) in the areas of Seoul and Gangwon province. The subjects were classified into 3 groups (low-stress, medium-stress and high-stress), and 59 students (18%) belonged the high-stress group. The BMI readings of the Gangwon province students are significantly higher than those of the Seoul students. The survey results show that the lunch frequency and vegetable intake levels are lower in the high-stress group, whereas the intakes of hot spicy food is higher in this group; they also show that Gangwon province students had eating habits that are relatively undesirable compared with the Seoul students. There are significant differences between the Seoul students and Gangwon porvince students regarding residence type, household economic level, types of leisure activities and level of some stresses. The Gangwon province students ate occasionally breakfast, lunch and snacks, but their midnight snack consumption is relatively frequent compared with the Seoul students. The results of the survey indicate that the BEPSI-K score has a negative correlation with the following variables : sleeping time, economic level of household, degrees of satisfaction regarding appearance and academic achievements, lunch frequency and vegetable intakes. Desirable eating habits are essential for the maintenance of a favorable health status and for the stress-management of university students who need to be a healthy members of society in the near future. To facilitate the formation of desirable eating habits among university students, community-based nutritional assistance and appropriate nutritional education programs should be considered necessary.

• Korean Journal of Community Nutrition
• /
• v.11 no.4
• /
• pp.520-533
• /
• 2006

The purpose of this study was to investigate satisfaction and preference for current military meal service and food behaviors and food habits of some military personnel in Chunchen and Wonju of the Kwangwon area. The results are as follows. In the anthropometric survey, average height of the subjects was 175.03 $\pm$ 5.30 cm, average weight was 69.15 $\pm$ 7.74 kg. As a result of surveying satisfaction in the current food service, an item high in satisfaction was adequacy of serving hours, whereas an item of low satisfaction was diversity of menu. The item of food service improvement needs of the subjects were in order more variety of menu, nutrition, preference, sanitation, cooking method. As a result of surveying eating behavior of the subjects, most items were high medium response. They preferred soju and relish and also they liked the bokkum cooking method. As a result of surveying food habits of the subjects, items of good habits were regularity of meals, marginal meals, diversity of food intake, dairy and dairy products, avoiding too exciting meals and natural food diet; whereas, items of bad habits were fast food intake, alcohol, smoking, carbonated and caffeine beverages, skipping breakfast. snacks, fatty food intake, yellow or green vegetable intake and fruit and seaweed intake. Following is the result of a survey on the preference of meals by cooking method serving the current military meal service. They liked one-dish meals such as Bokkeumbap, Bibimbap, Tteokguk, whereas, they disliked curryrice, Jajangbap. In case of soup, they liked soup made from meat better than vegetable soup or soup made with fish. Also they liked pot stem better than soup. Generally they liked meals containing meat in most cooking methods. These results suggest that continuous and practical nutrition education to change food habits in military life are necessary to Prevent chronic disease with increasing age.

• The Korean Journal of Mycology
• /
• v.20 no.4
• /
• pp.354-359
• /
• 1992

The effect of the addition of various vegetable oils on the mycelial growth was studied. Most vegetable oils were proved to be stimulative for the mycelial growth, and the best mycelial growth (12 mg/ml) was obtained with the addition of cotton seed oil. Several agricultural wastes i.e., rice straw, peanut hull, sawdust, rice hull, cocoa hull, coffee waste and beer waste were empolyed as substrates for sporophore production of p. sajor-caju. The biological efficiency(BE) for sporophore productions of rice straw and peanut hull were 36.4% and 32.6%, respectively. The highest yield of sporophore was obtained from the mixture of rice straw (50%) and beer waste (50%)(BE 109.6%) followed by peanut hull (50%) and beer waste (50%)(BE; 74.5%).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.16 no.3
• /
• pp.225-230
• /
• 1983

The proteolytic bacteria were isolated from the market foods such as ground beef, cooked shrimp meat, perch fillet, oyster meat, beef with textured vegetable protein and fish digest distributed at supermarket in Corvallis, Oregon, U.S.A. Two hundred and twenty-eight strains($30.8\%$) have proteolytic activity from 740 strains isolated from the examined samples and the strongest proteolytic strain among them was identified as a Streptococcus sp. Its maximum growth was showed at about 6 hours culture at $37^{\circ}C$ with shaking incubator in the medium added $0.15\%$ potassium phosphate monobasic and $0.4\%$ potassium phosphate dibasic, while the strongest activity of its extracellular protease was observed after 7 hours culture. The exoenzyme produced by the Streptococcus sp. was observed as a metal chelator sensitive protease, which are strongly inhibited by EDTA and o-phenanthroline but not affected by phenylmethylsulfonylfluoride and p-hydroxymercuribenzoate.

• Korean Journal of Plant Resources
• /
• v.31 no.6
• /
• pp.622-633
• /
• 2018

Chinese cabbage grown during autumn season is confronted with drought conditions for a certain period, especially during the early growth stage. In this study, we investigated the effects of drought stress on plant growth characteristics, as well as free amino acid, carotenoid, and proline in Chinese cabbage. Chinese cabbage seeds (Bulam Plus) were germinated, and all the seedlings were transplanted into plastic containers (28 cm diameter ${\times}$ 22 cm high) containing a commercial growth medium. The soil water content was measured and maintained at 10% for the drought-stressed plants and at 30% for the control plants, for three weeks. The results revealed that plant growth parameters were lower in the drought-stressed plants than in the control plants. The total free amino acid content tended to decrease in both drought-stressed and control plants with time. The total free amino acid content was found to be lower in the drought-stressed plants than in the control plants and the proline content was unaffected. Moreover, at three weeks after treatment, carotenoid content in drought stressed plants was significantly higher than that in the untreated plants. We believe that our study makes a significant contribution to the literature because the effects of drought stress on plant growth parameters, free amino acid, carotenoids, and proline accumulation in autumn growing cultivar of Chinese cabbage have not been widely studied in Korea, and our study provides valuable information in this regard, as Chinese cabbage is consumed throughout the year in Korea.

• Journal of Microbiology and Biotechnology
• /
• v.32 no.11
• /
• pp.1435-1446
• /
• 2022

Zinc-solubilizing bacteria can convert the insoluble form of zinc into soluble forms available to plants. This study was conducted to isolate and screen zinc-solubilizing actinobacteria from rhizosphere soils and to assess their effect on vegetable soybean growth. In total, 200 actinobacteria strains belonging to 10 genera were isolated from rhizosphere soil samples. Among these isolates, four showed zinc solubilization with solubilizing index values ranging from 3.11 to 3.78 on Bunt and Rovira agar supplemented with 0.1% zinc oxide. For the quantitative assay, in broth culture, strains CME34 and EX51 solubilized maximum available zinc contents of 529.71 and 243.58 ㎍/ml. Furthermore, indole-3-acetic acid (IAA) and ammonia were produced by these two strains, the strain CME34 produced the highest amount of IAA 4.62 ㎍/ml and the strain EX51 produced the highest amount of ammonia 361.04 ㎍/ml. In addition, the phosphate-solubilizing abilities in Pikovskaya's medium of CME34 and EX51 were 64.67 and 115.67 ㎍/ml. Based on morphological and biochemical characterization and 16S rDNA sequencing, the strains CME34 and EX51 were closely related to the genus Streptomyces. In a greenhouse experiment, single-strain inoculation of Streptomyces sp. CME34 or EX51 significantly increased the shoot length, root length, plant dry weight, number of pods per plant and number of seeds per plant of vegetable soybean plants compared to the uninoculated control. These findings facilitated the conclusion that the two Streptomyces strains have potential as zinc solubilizers and can be suggested as bioinoculants to promote the growth and yield of soybean.