• Parasites, Hosts and Diseases
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• v.36 no.1
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• pp.15-22
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• 1998

An in uitro culture technique was established for harvesting Strongwloides venezuelensis free-living infective larvae using a nutrient broth medium as a substitute for rat-feces in polyvinyl culture bags ($10{\;}{\times}{\;}12{\;}cm$). The egg hatch rate V) in sterile saline at different incubation temperatures (X) was expressed as the quadratic function, Y = $-0.192X^2$ + 8.673x - 19.550 (r = 0.901). The highest (100%) egghatch rate was observed at $25^{\circ}C$. A significant difference (p<0.05) in development rate W) of free-living infective larvae was observed between different concentrations of nutrient broth (X) which was highest (20.6%1 in 0.12% nutrient broth concentrations, incubated at $20^{\circ}C$ for 5 days [Y = $-864.032X^2$ + 245.995X- 0.560 (r = 0.875)]. Yields (Y) of infective larvae were observed relatively high when the culture medium was incubated at higher temperatures (X) which peaked at $25^{\circ}C$ (20.0%) than at lower temperatures. $15^{\circ}C$M (10.9%) and $20^{\circ}C$ (18.1%) [Y = $-0.189X^2$ + 8.387x- 72.795 (r = 0.981)]. The period W) required for the development of infective larvae decreased with higher incubation temperatures (X) [Y = $0.035X^2$ - 2.025X + 32.375 (r = 0.995)] The highest yield (19.2%) of infective larvae was obtained from culture bag inoculated with 15.000 eggs than with below and over 15,000 eggs in 0.12% nutrient broth and incubated at $25^{\circ}C$ for 4 days. The newly adapted culture method (from egg to third-stage larva) may be useful as a bio-bar/bioassay system for screening new chemical products, anthelmintics and pesticides, as well as for parasito immunological studies with Strongwloides species.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.225-236
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• 2019

BACKGROUND: Hydroponics is one of the methods for evaluating plant production using the inorganic nutrient solutions, which is applied under the artificial light conditions of plant factory system. However, the application of the conventional inorganic nutrients for hydroponics caused several environmental problems: waste from culture mediums and high nitrate concentration in plants. Organic nutrients are generally irrigated as a supplementary fertilizer for plant growth promotion under field or greenhouse conditions. Hydroponic culture using organic nutrients derived from the agricultural by-products such as dumped stems, leaves or immature fruits is rarely considered in plant factory system. Effect of organic or conventional inorganic nutrient solutions on the growth and nutrient absorption pattern of green and red leaf lettuces was investigated in this experiment under fluorescent lamps (FL) and mixture Light-Emitting Diodes (LEDs). METHODS AND RESULTS: Single solution of tomatoes (TJ) and kales (K) deriving from agricultural by-products including leaves or stems and its mixed solution (mixture ration 1:1) with conventional inorganic Yamazaki (Y) were supplied for hydroponics under the plant factory system. The Yamazaki solution was considered as a control. 'Jeockchima' and 'Cheongchima' lettuce seedlings (Lactuca sativa L.) were used as plant materials. The seedlings which developed 2~3 true leaves were grown under the light qualities of FL and mixed LED lights of blue plus red plus white of 1:2:1 mixture in energy ratio for 35 days. Light intensity of the light sources was controlled at 180 μmol/㎡/s on the culture bed. The single and mixture nutrient solutions of organic and/or inorganic components which controlled at 1.5 dS/m EC and 5.8 pH were regularly irrigated by the deep flow technique (DFT) system on the culture gutters. Number of unfolded leaves of the seedlings grown under the single or mixed nutrient solutions were significantly increased compared to the conventional Y treatment. Leaf extension of 'Jeockchima' under the mixture LED radiation condition was not affected by Y and YK or YTJ mixture treatments. SPAD value in 'Jeockchima' leaves exposed by FL under the YK mixture medium was approximately 45 % higher than under conventional Y treatment. Otherwise, the maximum SPAD value in the leaves of 'Cheongchima' seedlings was shown in YK treatment under the mixture LED lights. NO₃-N contents in Y treatment treated with inorganic nutrient at the end of the experiment were up to 75% declined rather than increased over 60 % in the K and TJ organic treatment. CONCLUSION: Growth of the seedlings was affected by the mixture treatments of the organic and inorganic solutions, although similar or lower dry weight was recorded than in the inorganic treatment Y under the plant factory system. Treatment Y containing the highest NO₃-N content among the considered nutrients influenced growth increment of the seedlings comparing to the other nutrients. However effect of the higher NO₃-N content in the seedling growth was different according to the light qualities considered in the experiment as shown in leaf expansion, pigmentation or dry weight promotion under the single or mixed nutrients.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.385-391
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• 2013

In this study, the availability of slurry composting and biofiltration (SCB) solution as an alternative for synthetic nutrient solution was determined by monitoring the growth, fruit yield, and fruit quality of cherry tomato (Solanum lycopersicum L. 'Unicon'). Treatments for nutrient solution were consist of SCB 1/2N, 1N, 2N, and commercial nutrient solution 1N (CNS 1N) based on nitrogen concentration (218.32 $mg{\cdot}L^{-1}$) of cherry tomato nutrient solution (control 1N). All nutrient solution including SCB solution (440~520 mL per day) was supplied to rock wool medium using a timer. After 31 days of transplanting, fresh and dry weights of shoots, leaf area, plant height, stem diameter, SPAD value and number of node were measured. After measuring growth characteristics of tomato plants, total fruit yield, ratio of marketable fruit yield, fruit weight, total soluble solids content, total acidity, total phenolic concentration, and antioxidant capacity were determined once a week for 7 weeks. As a result, among the SCB treatments, SCB 1/2N was similar to control 1N and CNS 1N in terms of fresh and dry weights of shoots, leaf area, stem diameter, number of node, and SPAD value. Increased N concentration of SCB inhibited the growth of tomato plants. Total fruit yield of SCB 1/2N was 47% of that of control 1N which showed the best result. Percentage of marketable fruit yield in SCB 1/2N was about 58%. Soluble solids contents, total acidity, total phenolic concentration and antioxidant capacity was the highest in SCB 2N and the other treatments were not shown any difference. Blossom-end rot rarely occurred in control 1N and CNS 1N while SCB treatments without Ca induced the physiological disorder of 7~19%. In conclusion, SCB 1/2N was good for the vegetative growth of cherry tomato plants but reduced yield and quality of fruit compared with control 1N and CNS 1N. Thus, it is possible to apply SCB solution to grow cherry tomato plants hydroponically but in the consideration of fruits yield and quality additional supply of several minerals would be required.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1398-1406
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• 2005

The purpose of this study was to investigate effects of web-based nutrition counseling on nutrient intake and blood glucose in type ll diabetic Patients. Forty type II diabetic patients, twenty one of them were diabetic patients without complication (Ncx-DM) and nineteen of them were diabetic patients with complication (Cx-DM), participated in a web-based nutrition counseling program. At the first nutrition counseling, the patients were counselled through interview and then follow up nutrition counseling was accomplished four times during eight weeks through tile web-based internet program. Various markers of disease risk including anthropometric indices, nutrient intake and blood glucose were measured before and after the nutrition counseling. After the nutrition counseling, body mass index and waist circumference decreased in both group but did not change significantly. Fasting blood glucose significantly decreased from 153.9 mg/dL to 139.0 mg/dL (p<0.05) in NCX-DM and from 178.2 mg/dL to 128.5 mg/dL (p<0.01) in Cx-DM after the nutrition counseling. Glycosylated hemoglobin level decreased from $9.3\%$ to $8,7\%$ in Ncx-DM and significantly decreased from $9.7\%$ to $7.8\%$ (p<0.01) in Cx-DM after the nutrition counseling. In addition, total cholesterol and LDL-cholesterol level significantly decreased in both group (P<0,05) after the nutrition counseling. Energy intake decreased significantly in Ncx-DM (P<0.05) and Cx-DM (p<0.01). Although the nutrient intake did not change significantly, the nutrient intake was improved after the nutrition counseling. Therefore, this study shows that the web-based nutrition counseling is effective in improving energy and nutrient intake and influences positively in blood glucose and serum lipids of the patients. In addition, these results indicate that the internet presents us with potential as a new medium for nutrition counseling in informationized society.

• Korean Journal of Community Nutrition
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• v.11 no.2
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• pp.180-190
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• 2006

The purpose of this study was to assess several indices of diet quality based on nutrient, food and food group intake of Korean adolescents based on several indices on diet quality according to residence area and body size. Using the data from the 1998 National Health and Nutrition Survey, twenty-four-hour-dietary recalls of a total of 1,110 Korean adolescents aged 13 - 19 years (male 543, female 567) were analyzed for nutrient adequacy ratio (NAR) , index of nutritional quality (INQ) , the number of foods (Dietary Variety Score, DVS) and food group consumed (Dietary Diversity Score, DDS) . In doing that, it was attempted to apply only the minimum amount of solid foods of Kant's without inclusion of liquid foods because of the very limited variety in Korean foods. Based on weight length index, 13.1% of the subjects were categorized as obese, 14.2%, overweight, 44.4%, normal and 28.3%, underweight. Only vitamin B2 intake was higher in the obese group than in the underweight group. There was no meaningful difference in energy, protein and fat intakes according to the grade of the body size. In terms of residence area, intake of fat, niacin, vitamin $B_6$ and folic acid were lower in the rural areas than in the metropolitan city. Only vitamin E intake was higher in the rural areas. Mean value of NARs (MAR) and INQs (mINQ) was also higher in the metropolitan city than in the rural areas, but there was no significant difference of these two values according to body size of the subjects. Mean DVS was 21.02 for total subjects, and has no difference between male and female and between metropolitan city and other medium-small city. But, the rural areas showed the lowest DVS of 19.05. Mean DDS in which five is a maximum score was 3.3 with no significant difference by sex and by residence area in male subjects. However, in female subjects, DDS in the rural areas was the lowest. According to body size of the subjects, there was no meaningful difference in both scores of DVS and DDS. In conclusion, most indices of nutrient intake and food and food group intake were not significantly different by body size of the subjects, while most indices were significantly different by residence areas: higher in the metropolitan city than in the rural area.

• Korean Journal of Soil Science and Fertilizer
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• v.15 no.4
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• pp.233-240
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• 1982

This study was conducted to elucidate the translocation pattern of photosynthate labelled by $^{14}C$ in rice cultivars and the effects of nutrient composition on the translocation in rice plant during ripening, Showing coincidence between the grain filling rate and the translocation of $^{14}C$ into the grain during ripening period, the translocation patterns of cultivars tested were grouped by three; 1) the late dominance type (Akibare), 2) the early dominance type (Taebaegbyeo, Chupungbyeo), and 3) the semi-late dominance type (Milyang #23, Milyang #42, and Yushin). The negative relation ship existed between the translocation ratio of $^{14}C$ into the grain and the nitrogen content in plants, but not significant, The nutrient depletion of P, K, Ca, Mg, and Si in water medium from the panicle initiation to the heading stage resulted in the decrease of grain weight by 4 to 12 percent and the increase of translocation of $^{14}C$ into grain assimilated at heading. The effect of resupply of these nutrients after heading was recognized by the order of P>Mg>K and Ca. But the effect of Si resupply was hardly recognized in increasing grain weight. The photosynthetic rate was greatly affected by the nitrogen status and the depletion of P, K, and Ca decreased the photosynthetic rate in single leaf at heading, while the depletion of Si enhanced the rate.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1643-1653
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• 2018

Objective: This study investigated the effect of dietary crude protein (CP) supplementation on nutrient intake, nitrogen (N) utilisation, blood metabolites, ruminal fermentation and growth performance of young Holstein bulls. Methods: Twenty-one young bulls weighing $277{\pm}11.2kg$ were equally divided into three groups and were offered diets formulated with low CP (LCP; 10.21% CP and 4.22% rumen degradable protein [RDP]), medium CP (MCP; 12.35% CP and 5.17% RDP) and high CP (HCP; 14.24% CP and 6.03% RDP). Yellow corn silage was used as a unique forage source and was mixed with concentrate. This mixed feed was given ad libitum to the young bulls included in the study. Results: Results showed that CP intake, blood urea nitrogen, N intake, total N excretion and N balance increased linearly with an increase in dietary CP level (p<0.05). However, no significant difference was observed in nutrient digestibility among the bulls receiving the different diets. Ruminal pH (p<0.05) and ammonia nitrogen ($NH_3-N$) concentration (p<0.01) were significantly higher in the bulls receiving the MCP and HCP diets than in those receiving the LCP diet. The bulls receiving the HCP diet showed significantly higher ruminal bacterial protein level, propionate, acetate and total volatile fatty acid (TVFA) concentrations than bulls receiving the LCP diet (p<0.05). Moreover, dietary CP level exerted a significant positive effect on the final body weight, average daily gain and gain-to-feed ratio of the bulls (p<0.05). Conclusion: High dietary CP level is optimal for achieving maximum growth and high profitability without exerting a negative effect on the physiology of growing Holstein bulls.

• The Korean Journal of Mycology
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• v.27 no.1 s.88
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• pp.1-9
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• 1999

For the practical using of liquid spawn we carried out selection test of nutrient sources, cultural methods and cultural apparatus for liquid spawn production of oyster mushroom(ASTI 2001, ASTI 2018, ASTI 2072, ASTI 2016, ASTI 2070, ASTI 2180, ASTI 2183, ASTI 2042). The optimal temperature and pH range for mycelial growth of Pleurotus species were $25^{\circ}C\;to\;30^{\circ}C$ and 5.5 to 6.5, respectively. The effect of carbon sources, nitrogen sources and mineral salts on the mycelial growth was studied using petridish culture. Generally, the disaccharides and polysaccharides showed good effect for mycelial growth of Pleurotus species, and the polysaccharides were superior to the other classes of carbon sources for mycelial growth. For the mycelial growth of the 8 oyster mushroom stains, soybean flour was superior to the other kinds of nitrogen sources. On the other hand, addition of mineral salts did not affect, and even poor under certain mineral salts, the mycelial growth of the 8 oyster mushroom stains. The brown sugar selected out the carbon source of the agricultural medium. Also the soybean flour selected out the nitrogen source of agricultural medium. In the medium selection, we selected out agricultural optimum medium composed of brown sugar 3%, soybean flour 0.3%, potassium phosphate 0.05%, magnesium sulfate 0.05%. Under the 250 ml erlenmeyer culture, the effects of such factors as the inoculum rate, the working volume, cultural method and flask shapes on the mycelial growth were examined. The optimal inoculum rate and working volume on the mycelial growth of oyster mushroom was 2 mycelial disk (diameter 6 mm) and 100 ml, respectively. The shake flask culture was enhanced the mycelial growth than at the erlenmeyer flask. Pulp form growth of mycelium in the erlenmeyer flask culture was obtained in the culture with glass rod of length 50 mm, diameter 10 mm.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.189-201
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• 1976

In an effort to develop a microbial in secticide, B. thdringiensis var. thuringiensis was cultured in the medium composed of cocoon-cooked water from a filature. The results obtained are summarized as followss : (1) Bacillus thuringiensis is a bacterium producing a ${\delta}-endotoxin$ especially toxic to lepidopterous insects and a thermostable exotoxin harmful to dipterous insects. (2) With a view to utilizing the cocoon-cooked water discarded from the filature, as a nutrient source in the B. thuingiensis culture, it was analyzed to contain large amounts of various minerals and protein (7.5 mg/ml) believed to be extracted from the pupae. (3) A large amount of the ${\delta}-endotoxin$ can be obtained most cheeply by using cocoon-cooked water instead of distilled water in preparing GYS and citrate salts media. (4) The largest amount of a mixture of the vegetative cells, spores, and crystals was obtained by addition of 8 gr/l of glucose to the GYS medium. (5) The growth of the bacterium was far better, when leucine, isoleucine, and valine were added all together to the citrate salts medium to the concentration of $1.25{\times}10^{-3}M$. (6) The best growth was observed by addition of Na-glutamate to the citrate salts medium to the concentration of $2.5{\times}10^{-3}M$. (7) The optimal culture time ranged from 9 to 15 days. (8) The highest mortality was shown in Pieris rapae Linne with a pH of the total body extract of 8.4, whereas Dendrolimus spectabilis Butler and Bombyx mori Linne with lower pH's were less susceptible to the ${\delta}-endotoxin$. (9) The presence of the thermo stable exotoxin was confirmed by the fact that the supernatant of the culture was very toxic to the Drosophila melanogaster tested.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.461-465
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• 2005

To determine the cause of wet noodle spoilage, microorganisms isolated from wet noodles were identified and characterized. In addition, the growth inhibitory effects of organic acid mixture (OA: lactic acid 27.8%, acetic acid 12.0%, succinic acid 1.0%) and sodium dehydroacetate (SD) on the isolated strain were estimated in nutrient broth medium. The isolated strain was Gram-positive, rod shaped, motile, and spore forming. Based on physiological characteristics and the API 50 CHB-kit test results for the assimilation of 49 carbohydrates, the isolated strain was identified as Bacillus amyloliquefaciens (92.6%), which is able to degrade starch. Decimal reduction times (D-values) at 100, 105, and $110^{\circ}C$ for spores of B. amyloliquefaciens were 8.5, 5.1, and 2.5 min, respectively, and the z-value was $12.8^{\circ}C$. We estimated that B. amylo-liquefaciens isolated from spoiled wet noodles was a thermophilic species having high heat-resistance. Viable cell numbers in wet noodles and broth medium inoculated with B. amyloliquefaciens were decreased by 2-4 log cycles by combined treatment with 0.03 or 0.05% OA and 0.3% SD. These results revealed that OA combined with SD could be used as a potential agent to inhibit B. amyloliquefaciens in wet noodles.