• 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.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.265-270
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• 1993

In order to retain the freshness of fruits and vegetables and to reduce the rate of disease damage, grafruit seed extract (GPSE), natural microorganism control agent, was applied during the preservation process of fresh fruits and vegetables. GFSE showed an effective inhibitory action against plant putrefactive bacteria and fungi which were involved in the decay of fruits and vegetables. Minimal inhibitory concentrations for GFSE against the microbes were in the range of 50 to 2,000 ppm. Direct observation of microbial cells and spores using electron microscopy showed their function was destroyed by the treatment of the dilute solutions of GFSE. Fresh Welsh onions, onions and red peppers treated with GFSE and stored in polyethylene film (0.1 mm) retained better quality in color and texture than the non-treated control. GFSE was efficient in controlling the germination of potatoes. It was observed that GFSE would reduce disease damages and have bactericidal and fungicidal properties during the storage of such fruits and vegetables as zucchinis, cucumbers, tomatoes and mandarin oranges.

• KSBB Journal
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• v.29 no.3
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• pp.145-154
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• 2014

A fresh vegetable and fruit juice has become a new healthy food available for detoxification, dieting and health. This paper presents the useful information about the quality changes of fresh juice according to different juicer. Quality of fresh juice could be evaluated by several factors such as juice yield, enzyme activity, antioxidant activity, polyphenol contents, and anti-inflammatory activity. The juice yields of 12 different vegetables and fruits were compared using 6 different juicers and it was observed that the yield of slow juicer was better than that of conventional blender. Among 12 samples, the juice yield of grape is the best and the pH of the juice was in the acidic range of 3 and 4. Kiwi and grapefruit were the best in terms of protease enzyme activities by Hemoglobin units on the tyrosine basis and Spectrophotometric acid protease unit and papain units on the tyrosine basis of KFDA protocols. The total polyphenol contents were also high in kiwi and grapefruit. The antioxidant activity by diphenyl-1-picrylhydrazyl (DPPH), superoxide dismutase (SOD), and radical scavenging assay were high in the order of kiwi, grapefruit, grape, tomato, and orange. Anti-inflammatory activities were also assay for 12 samples with 6 juicers. It can be concluded that of fresh fruit and vegetable juice provides a source of antioxidant components and enzymes with high activity. And the enzyme activities could be used as one of the quality indicator of fresh juice. Concerning the juicers used in this study, slow juicer could be recommended to prepare the fresh juice in terms of the juice quality.

• Journal of Microbiology and Biotechnology
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• v.28 no.11
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• pp.1896-1907
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• 2018

Salmonellosis is commonly associated with meat and poultry products, but an increasing number of Salmonella outbreaks have been attributed to contaminated vegetables and fruits. Enteric pathogens including Salmonella enterica spp. can colonize diverse produce and persist for a long time. Considering that fresh vegetables and fruits are usually consumed raw without heat treatments, Salmonella contamination may subsequently lead to serious human infections. In order to understand the underlying mechanism of Salmonella adaptation to produce, we investigated the transcriptomics of Salmonella in contact with green vegetables, namely cabbage and napa cabbage. Interestingly, Salmonella pathogenicity island (SPI)-1 genes, which are required for Salmonella invasion into host cells, were up-regulated upon contact with vegetables, suggesting that SPI-1 may be implicated in Salmonella colonization of plant tissues as well as animal tissues. Furthermore, Salmonella transcriptomic profiling revealed several genetic loci that showed significant changes in their expression in response to vegetables and were associated with bacterial adaptation to unfavorable niches, including STM14_0818 and STM14_0817 (speF/potE), STM14_0880 (nadA), STM14_1894 to STM14_1892 (fdnGHI), STM14_2006 (ogt), STM14_2269, and STM14_2513 to STM14_2523 (cbi operon). Here, we show that nadA was required for bacterial growth under nutrient-restricted conditions, while the other genes were required for bacterial invasion into host cells. The transcriptomes of Salmonella in contact with cabbage and napa cabbage provided insights into the comprehensive bacterial transcriptional response to produce and also suggested diverse virulence determinants relevant to Salmonella survival and adaptation.

• Nutrition Research and Practice
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• v.6 no.3
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• pp.232-237
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• 2012

This study was done to explore the effect of Korean women's salt usage behavior on their sodium intake and excretion according to aging. Dietary sodium intake and salt usage behavior were analyzed to compare the difference between young and middle-aged women. One hundred fifty six young women and 77 middle-aged women without hypertension or any current medication were recruited. Body mass index, waist hip ratio, blood pressure were measured from each subject. Salt usage behaviors were surveyed with questionnaire, sodium intake with 24-hr recall method, and sodium excretion with spot urine. Middle-aged women were more obese than young women according to body mass index and waist hip ratio. Blood pressure was significantly higher for the middle-aged. Young women consumed more fats and middle-aged women more carbohydrates. Middle-aged women consumed more sodium and potassium, and excreted more sodium. Among questionnaire items, kimchi, soup or pot stew, or salted vegetables were found to be related with high sodium diet. Salted vegetables and salted nuts and potato chips were significantly correlated with young women's high sodium diet, while soy sauce on fried food, kimchi, salted vegetables accounted for middle-aged women's high sodium diet. With these results, we concluded that middle-aged women consumed more carbohydrates, less fat, and more sodium and potassium than young women. Middle-aged women frequently choose kimchi, soup or pot stew, or salted vegetables, and they contribute to high sodium intake. We recommend to choose low-salt kimchi, less soup or pot stew, and more fresh vegetables for lower sodium diet.

• The Korean Journal of Food And Nutrition
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• v.36 no.3
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• pp.185-192
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• 2023

This study analyzed the chemical characteristics and physiological activity of five kinds of fresh vegetables produced in trees in early spring and tried to use them as basic data for wild vegetable producers and processed food manufacturers using wild vegetables. The crude protein, minerals, ascorbic acid, folate, total phenol, total flavonoid, DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity and ACE (angiotensin converting enzyme) inhibitory activity were determined. Five spring wild vegetables contain high protein and phosphorus, indicating that they are useful food ingredients as sources of protein and phosphorus. Vitamin C content was high in R. venicifera and C. sinensis shoots, and in particular, R. venicifera and A. cortex shoots have high folic acid (folate) contents of 1,903.91 ug% and 1,525.35 ug%, respectively, which is considered a good food for folic acid intake in spring. The total phenol content was between 0.52% and 1.27%, and it was the highest in C. sinensis of 1.27%, followed by the order of R. venicifera, A.cortex, K.pictus, and A. elata, which tended to be consistent with the total flavonoid content. As for DPPH radical scavenging ability, C. sinensis (55.93%) showed the highest activity, and ACE inhibitory activity showed the highest activity in A. cortex (88.04%).

• Korean Journal of Agricultural Science
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• v.50 no.4
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• pp.967-976
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• 2023

Biochar is emerging as a promising substance for achieving carbon neutrality and climate change mitigation. It can absorb several nutrients via ion bonding on its surface functional groups, resulting in slow dissociation of the bonds. Biochar, like organic fertilizers, contributes to sustainable nutrient management. The purpose of this study was to investigate the effects of nutrient-coated biochar amendments on leafy vegetables production and soil fertility. The nutrient-coated biochar was produced by soaking rice husk biochar in a nutrient solution containing nitrogen (N), phosphorus, and potassium for 24 hours. Nutrient-coated biochar and organic fertilizers were applied to soil at a rate of 120 kg·N·ha^-1. The growth components of the leafy vegetables showed that nutrient-coated biochar led to the highest fresh weight (FW) of both lettuce and kale (i.e., 146.67 and 93.54 g·plant^-1 FW, respectively). As a result, nutrient-coated biochar amendments led to superior yield compared to the control treatment and organic fertilization. The elemental composition of leafy vegetables revealed that soil amended with nutrient-coated biochar resulted in higher nutrient contents, which was attributed to the high nutrient contents supplied by the rice husk biochar. Soil amendment with nutrient-coated biochar positively enhanced the soil fertility compared to amendment with organic fertilizer. Therefore, nutrient-coated biochar is a promising substance for enhancing agronomic performance of leafy vegetables and improving soil fertility.

• Journal of Nutrition and Health
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• v.10 no.4
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• pp.104-110
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• 1977

Vegetables are liberally taken to enhance the mineral, vitamin, and rouphage value of the diet. And calcium is an essential mineral at all ages, although the daily requirement varies with physiological status of the individual. On the other hand, oxalic acid is an unwanted constituent of several clinical disorders. It is therefore necessary to take into account the calcium as well as the oxalic acid content of the various calcium, foods. Oxalic acid, calcium, calcium/oxalic acid ratio and available calcium have been determined in 31 kinds of the Korean common vegetables. The results are summarized as follows; 1. The highest content of oxalic acid has been recorded in Amaranth. spinach and beet. It is respectively 1,100mg%, 619mg%, 550mg% in fresh sample. It is comparatively high in Leek, leavels of perilla, Mugwort, Chyi-leaves, green red pepper, Burdock. 2. Many vegetables have been calculated as below 2.0 in the calcium/oxalic acid ratio. 3. Avaiable calciumis much in Malaolitoria, Lettuce, Green onion whole, Green garlic, Wild onion, Cabbage and Radish root. 4. A food calendar is suggested as a guide to the proper selection of food items for normal individuals and for those suffering from urolithiasis, cardiovascular disease or calcium deficiency status.

• Journal of Nutrition and Health
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• v.27 no.1
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• pp.59-69
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• 1994

Dietary fiber(DF) intakes of Korean during 1969∼1990 were estimated and the major food sources of fiber were analyzed using the data from the Annual Reports of Korean National Nutrition Survey. The estimated daily DF intake of Korean has gradually decreased during the 22 years, from 24.46g in 1969 to 17.31g in 1990 with a remarkable decline in 1987. The average DF intakes of the rural population were higher than those fo urban's until 1980, but the situation was reversed until 1987 and the regional difference in DF consumption disappeared thereafter. Vegetables, cereals, grain and legumes were the major sources of fiber for Korean in recent 5 years(1986∼1990), providing 32%, 16% and 19% of DF intake respectively. Throughout the 22years, the intakes of DF from cereals and fresh vegetables have been reduced and those from processed vegetables, seaweeds and fruits has been increased. Df intake from legumes continuously increased until 1986, and it decreased thereafter. Rural population consumed more fiber from cereals than the urban's during the 1970s, but thereafter regional difference in cereal fiber intakes became insignificant. Urban population consumed more fiber from legumes and fruits than the rural's through the entire period. The results of this study indicate that the present DF intake of Korean is considerably lower than generally anticipated and is below the tentative recommended DF intake and thus higher DF intake than the present level is needed.

• Journal of Food Hygiene and Safety
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• v.34 no.6
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• pp.526-533
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• 2019

The purpose of this study was to investigate hazardous microorganisms in mixed baby leafy vegetables and various baby leafy vegetables used as raw materials for fresh-cut produce in spring and summer. To estimate microbial loads, a total of 298 samples including 181 samples of mixed baby leafy vegetables purchased in a Korean market and 117 samples of various baby leafy vegetables from distribution companies were collected. Fecal indicators (coliform and Escherichia coli) as well as food-borne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus) were enumerated. As a result, the mixed baby leafy vegetable samples showed significantly higher (P<0.05) coliform bacteria numbers in summer (5.59±1.18 log CFU/g) compared to spring (3.60±2.53 log CFU/g). E. coli was detected in 1.3% (1/79) and 42.2% (43/102) of samples collected in spring and summer, respectively. Only one sample collected from a market in spring was contaminated with S. aureus. In the experiment with baby leafy vegetables, the number of coliforms detected in baby leafy vegetables cultivated in soil in spring was 1.15±1.95 log CFU/g, and that in summer was 4.09±2.52 log CFU/g. However, the number of coliforms recovered from baby leafy vegetables cultivated in media was above 5.0 log CFU/g regardless of season. Occurrences of E. coli were 44.4% (12/27) and 19.0% (4/21) for baby leafy vegetables cultivated in soil and media, respectively. However, E. coli O157:H7 and Salmonella spp. were not detected. These results are in relation to microbial loads on mixed baby leafy vegetables associated with raw materials. Therefore, it is necessary to develop and implement hygienic practices at baby leafy vegetable farms to enhance the safety of fresh produce.