• Korean Journal of Agricultural Science
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• v.49 no.3
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• pp.397-405
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• 2022

Castor oil cake is widely used as a raw material for organic fertilizers (OF) in Korea. Compared to other fertilizer raw materials, it is highly dependent on imports. In terms of replacing raw materials, dehydrated food waste powder (FDP) and castor oil cake have similar nutritional content, and if 30% is replaced, about 20% of the raw material cost can be saved. However, few studies on the effects on crop growth and soil properties when organic fertilizer and dry food waste powder are mixed and applied to the soil have been reported. The effects of an organic fertilizer made by mixing the commercial available organic fertilizer with dehydrated food waste (OF + FDP) on soil properties and the growth of two types of leafy vegetables (lettuce and young radish) were evaluated and compared with the performance of OF. The fresh weights of lettuce and young radish were the highest with OF amendment and stood at 114.3 and 119.0 g·plant^-1, respectively. These were followed by OF + FDP amendment, which produced 103.1 and 109.6 g·plant^-1, respectively. Compared to the control, OF and OF + FDP increased the lettuce fresh weights by about 69% and 52%, respectively, while the fresh weights of the radish were increased by about 223% and 207%, respectively. The soil pH, EC, total carbon content, and organic matter content in OF and OF + FDP increased. The mixture of dehydrated food waste powder and organic fertilizers is expected to improve soil quality and facilitate stable production of crops and contribute to the substitution of imported organic fertilizer raw materials.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.518-524
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• 2014

Heavy metal pollution in agricultural field near at the abandoned metal mines has been a critical issue in Korea. In particular, bioaccumulation in plants can have detrimental effect on human health. Main objective of this research was to examine arsenic (As) concentration in soil with varied extraction methods and to determine bioaccumulation and biological transfer factor in different crops. Results showed that bioaccumulation ratio of As for total contents in soil was ordered leafy and stem vegetables (1.19%) > fruit bearing vegetables (0.79%) > pulses (0.40%) > root vegetables (0.36%) with different crop species. Among 6 different extraction methods, all of extraction methods showed high correlation ($R^2=0.87-0.97$) except DTPA ($R^2=0.25$) when comparing As concentration in soil extracted with different extractants and As concentration in each crops. Calculated biological transfer factor was ranged 0.002-0.018 depending on crop species. Overall, concentration of As in crops can be varied and best management practice for minimizing bioaccumulation of As should be considered depending on crop species.

• Journal of Food Hygiene and Safety
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• v.19 no.1
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• pp.9-11
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• 2004

Safety evaluation of lead and cadmium were taken in Kimchi, of which imports is on the increase. The results showed that the levels of lead and cadmium in domestic Kimchi were 0.2964 mg/kg and 0.0637 mg/kg, and the levels in imported Kimchi were 0.3557 mg/kg and 0.0656 mg/kg, respectively; the difference was not significant. Compared with the previous results, the contamination levels of Kimchi, which are composed of various vegetables, were higher than those of vegetables or leafy vegetables. Ingestion levels of heavy metals were lower than the PTWI by mean values or simulation results, but the total safety evaluation must be taken in every food category.

• Korean Journal of Community Nutrition
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• v.14 no.5
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• pp.531-544
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• 2009

This study was conducted to survey multiple factors of aversion to vegetables and preferences for vegetable-related recipes in school meal services among elementary school children in order to help develop various menus and recipes for school meal services. Questionnaire survey was carried out with the study subjects, who were 401 children in 6th grade attending elementary schools in Chonnam and Kwangju metropolitan regions. Results from the survey can be summarized as follows: 65.1% of respondents answered they try to eat vegetables and other namul side dishes served in school meal service for health. As for the frequency of taking vegetables and namul side dishes out of daily meals, 47.4% of respondents chose 'once or twice'. The reasons for aversion to vegetables in boys were taste and cooking method, while girls were taste and feeling between teeth. In boys there were no differences between regions of Kwangju and Chonnam but the tendency of aversion to vegetables was significantly high in girls. As for the aspects of vegetable aversion of subjects, 46.9% of respondents took up 'black & purple' in the unfavorable color of vegetables. 49.1% in 'bitterness' and 39.2% in 'greasiness' were in terms of the aversive taste of vegetables. The aversive vegetable recipes were 58.6% in 'raw & seasoned' and the unfavorable feeling of vegetables were 53.1% in 'squashiness'. There were differences between regions of Kwangju and Chonnam with boys in color and cooking method in girls. Results from the survey on their preferences for vegetable recipes showed that leafy vegetables like crown daisy (raw/slightly seasoned) and pak choi (broth/pot stew) fell to the most aversive category, while bean sprouts (broth/pot stew) were chosen as the most favorable one. Among root vegetables bell-flowers were found to belong to the least preferred recipe, while potatoes were proven to be most preferable in terms of recipes. As for fruit vegetables and other vegetables, all respondents didn't like 'fatsia shoots' vegetable and it's cooking method and they preferred 'green pumpkins (broth/pot stew)'. In respect of mushrooms, enoki mushroom (broth/pot stew) was found most preferred and had high tendency of preferences in boys and girls in Kwangju compared with Chonnam region. The study results indicated that respondents did not show big differences in factors influencing them to be averse to vegetables and their preferences for vegetable recipes depending on regions. In order to have high preference and intake in children's diets, it needs to study in reform of menu about using namul or vegetables mixed with meats and fruits that children preferred or applying roasted and fried other less than namul.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.326-331
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• 2009

This study was carried out to evaluate the effects of row cover materials supported by flexible FRP frames with three kinds of non-woven fabric, and five kinds of net in leaf vegetable cultivation. Leaf radish (Raphanus sativus L.), Chinese cabbage (Brassica rapa L. ssp. pekinensis) were sown on May 21, 2003, and leaf lettuce (Lactuca sativa L.) was planted at the same date in Agricultural Research Center for Climate Change, Jeju, Korea. Net coverings showed higher light transmittance than in non-woven fabric coverings. The average air and soil temperatures increased by $0.3{\sim}1.0^{\circ}C$ in net coverings and $0.5{\sim}3.0^{\circ}C$ in non-woven fabric coverings, respectively. There was no difference in relative humidity among the covering materials. All the vegetables showed higher growths and yields in non-woven coverings than in non-covering. The yields increased 81% in leaf lettuce, 58% in leaf radish, and 93% in Chinese cabbage, respectively. In addition, the insect damages were considerably reduced in the row covering plots than in the control, especially in non-woven fabric coverings.

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.35-39
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• 2002

This study was conducted to investigate the effect of early $CO_2$ enrichment during seedling stage on long-term $CO_2$ enrichment after transplanting in the culture of pat-choi (Brassica campesris L), spinach (Spinacia oeracea L.), and leaf lettuce (Lactuca saliva L). During seedling stage, $CO_2$enrichment had significantly higher fresh and dry weight and leaf area of the top parts (above ground) of all three plant species than the control (no $CO_2$ enrichment). About 53%, 70% , and 40% increase in fresh weight of the top parts of pak-choi, spinach, and leaf lettuce were observed, respectively. Also, in seedling stage, dry weights of roots of spinach and leaf lettuce were significantly increased by early $CO_2$ enrichment. Relative fresh weight increment, compared with fresh weight of the control, in the top parts of roll three plants showed the highest values in 10 days after $CO_2$ enrichment treatment. In the long-term $CO_2$ enrichment experiment, early $CO_2$ enrichmented plants had 20% greater leaf area than the control in all three leafy vegetables. Fresh and dry weights of top parts of early $CO_2$-treated plants were also increased from 10 to 20%, as compared with the control plants. However, these increasement rates in the long-term $CO_2$ enrichment were lower than those seedling stage, which had 30-60% increment-rates. After transplanting, photosynthetic rate of each leafy vegetable in the control treatment slowly decreased, but those rates of early $CO_2$ enriched plants rapidly decreased.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2001.10a
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• pp.171-174
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• 2001

Solid phase micro-extraction (SPME), a solvent-free, rapid and inexpensive method for the extraction of organic compounds from aqueous sample matrices, was evaluated for determination of the 120 pesticides in vegetables such as crown daisy, perilla leaf, leafy lettuce and to mato. The analysis conditions were chosen for the SPME method: 15 min of immersion of the PDMS fiber in 10 ml of the solution with stirring at 1,000 rpm. The recovery tests were carried out in triplicate. The range of recoveries was 0-142% for organochlorine pesticides and $4.9\sim200\%$ for organophosphorus pesticides. The recoveries were very low in the pesticide groups with low solubility in water. The recoveries became lower in proportion to the interference materials in vegetables. The recovery in tomato was relatively higher than that in perilla Ie af and crown daisy. The recovery values obtained by SPE and SPME were compared. In leaf y lettuce, recovery obtained by SPE method ranged from $58.1\%\;to\;136.1\%$ and recovery by SPME ranged from $9.6\%\;to\;176.3\%$ In organophosphorus pesticides. The recovery in SPME method was satisfactory with $136\%$ for ethoprophos, $119\%$ for methidathion and $113\%$ for diazinon. Meanwhile, recovery of EPN, phenthoate and 2,4-DDT revealed relatively low value of $38\%,\;41\%\;and\;3.4\%,$ respectively. However, most of pesticides applied to SPME method sho wed constant recovery and precision. From these results, it can be concluded that solid phase micro-extraction might be an appropriate method for the screening test of pesticides in vegetables.

• Nutrition Research and Practice
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• v.16 no.4
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• pp.489-504
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• 2022

BACKGROUND/OBJECTIVES: This study examined socio-economic differences in diverse food consumption among children 6-23 months of age in South Asia and Southeast Asian countries. SUBJECTS/METHODS: Data from Demographic and Health Surveys in four countries in South Asia (n = 15,749) and four countries in Southeast Asia (n = 10,789) were used. Survey-design adjusted proportions were estimated for the following 10 food items: grains, legumes, dark green leafy vegetables (DGLV), vitamin A-rich fruits, vitamin A-rich vegetables, other fruits and vegetables (OFV), fish, meat, dairy, and eggs. An equity gap was defined as an arithmetic difference in the proportion of each food item consumed in the past 24-hours between the wealthiest and lowest quintiles and between rural and urban areas, denoted by percentage points (pp). RESULTS: The consumption of most of the 10 food items was higher in the wealthiest quintiles and urban areas across eight countries. The size of equity gaps was greater in Southeast Asia than in South Asia, particularly for vitamin A-rich fruits (3.3-30.0 pp vs. 0.3-19.6 pp), vitamin A-rich vegetables (12.1-26.7 pp vs. 2.4-5.9 pp), meat (17.7-33.4 pp vs. 3.4-13.4 pp), and dairy (14.7-32.5 pp vs. 3.3-11.4 pp). However, the size of equity gap in egg consumption was greater in Southeast Asia than South Asia (11.2-19.8 pp vs. 11.0-26.7 pp). Relatively narrower gaps were seen in the consumption of grains (0.3-12.9 pp), DGLV (0.6-12.4 pp), and fish (0.1-16.8 pp) across all countries. CONCLUSIONS: Equity gaps in food consumption differed by socio-economic status and region. Reducing equity gaps in nutrient-rich foods and utilizing regionally available food resources may increase child dietary quality.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.833-847
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• 2016

Drought stress is a major agricultural limitation to crop productivity worldwide, especially by which leafy vegetables, plant leaves eaten as vegetable, could be more lethal. The study was carried out to know the effect of drought tolerance plant growth promoting bacteria (PGPB) on water stress of kale seedlings. A total of 146 morphologically distinct bacterial colonies were isolated from bulk soil and rhizosphere soil of leafy vegetables and screened for plant growth promoting microbioassay in greenhouse. Out of them the isolate SB19 significantly promoted the growth of kale seedlings in increasement of about 42% of plant height (14.1 cm), 148% of leaf area ($19.0cm^2$) and 138% of shoot fresh weight (1662.5 mg) attained by the bacterially treated plants compared to distilled water treated control (9.9 cm, $7.7cm^2$, 698.8 mg). Shoot water content of SB19 treated kale seedlings (1393.8 mg) was also increased about 152% compared with control (552.5 mg). The SB19 isolated from bulk soil of kale plant in Iksan, Korea, was identified as species of Bacillus based on 16S rRNA gene sequencing analysis. We evaluated the effect of drought tolerance by the Bacillus sp. SB19 on kale seedlings at 7th and 14th days following the onset of the water stress and watering was only at 7th day in the middle of test. In the survey of 7th and 14th day, there were mitigation effect of drought stress in kale seedlings treated with $10^6$ and $10^7cell\;mL^{-1}$ of SB19 compared to distilled water treated control. Especially, there were more effective mitigation of drought damage in kale seedlings treated with $10^7cell\;mL^{-1}$ than $10^6cell\;mL^{-1}$. Further, although drought injury of bacterially treated kale seedlings were not improved at 14th day compared with 7th day, drought injury of $10^7cell\;mL^{-1}$ of SB19 treated kale seedlings were not happen rapidly but developed over a longer period of time than $10^6cell\;mL^{-1}$ of SB19 or control. The diffidence of results might be caused by the concentration of bacterial suspension. This study suggests that beneficial plant-microbe interaction could be a important role of enhancement of water availability and also provide a good method for improving quality of leafy vegetables under water stress conditions.

• Journal of Food Hygiene and Safety
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• v.21 no.4
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• pp.250-257
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• 2006

The purpose of this study is to evaluate microbiological contamination of leafy vegetables. Total aerobic bacteria and coliforms were monitored to get the contamination levels and Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Escherichia coli, Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni to detect pathogens with risk of foodpoisoning from fresh vegetables. The colony count of total aerobes and coliforms was also performed to determine the efficacy of washing with tab water by common consumers. 124 samples which are divided into 8 kinds of vegetables - Sesame leaf, Dropwort, Chinese cabbage, Korean leek, Lettuce, Crown daisy, Pimpinella brachycarpa, Chicory were sampled in 2 wholesale markets in Incheon. Mean counts of total aerobic bacteria for individual vegetables ranged from $2.2\times10^6\;CFU/g\;to\;6.0\times10^7\;CFU/g$ and total coliforms were from $4.1\times10^5\;CFU/g\;to\;9.8\times10^6\;CFU/g$. Both show the peaks in summer on this study from March to September. Decrease rates after washing with tab water averaged 81.0% and 82.5% in total aerobic bacteria and coliform counts respectively. Staphylococcus aureus was isolated 8.1%, Bacillus cereus 14.5%, Clostridium perfringens 5.6%, Escherichia coli 18.5%. 11 samples showed overlapped bacterial contamination. For respective vegetables Staphylococcus aureus isolated from 0.0% to 22.2%, Bacillus cereus from 0.0% to 29.4%, Clostridium perfringens from 0.0% to 23.1 %, Escherichia. coli from 0.0% to 35.0%. Escherichia coli O157:H7, Salmonella spp., Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Campylobacter jejuni were not isolated. This study is expected to be available as the reference for the basal data of pathogens in fresh vegetables.