• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.357-366
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• 2011

BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.

• Journal of Biosystems Engineering
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• v.39 no.3
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• pp.227-234
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• 2014

Purpose: The aim of this research was to develop and evaluate natural hydroxyapatite (HA) ceramics produced from the heat treatment of pig bones. Methods: The properties of natural HA ceramics produced from pig bones were assessed in two parts. Firstly, the raw materials were characterized. A temperature of $1,200^{\circ}C$ was chosen as the calcination temperature. Fine bone powders (BPs) were produced via calcinations and a milling process. Sintered BPs were then characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and a 2-year in vitro degradability test. Secondly, an indirect cytotoxicity test was conducted on human osteoblast-like cells, MG63, treated with the BPs. Results: The average particle size of the BPs was $20{\pm}5{\mu}m$. FE-SEM showed a non-uniform distribution of the particle size. The phase obtained from XRD analysis confirmed the structure of HA. Elemental analysis using XRF detected phosphorus (P) and calcium (Ca) with the Ca/P ratio of 1.6. Functional groups examined by FTIR detected phosphate ($PO{_4}^{3-}$), hydroxyl ($OH^-$), and carbonate ($CO{_3}^{2-}$). The EDX, XRF, and FTIR analysis of BPs indicated the absence of organic compounds, which were completely removed after annealing at $1,200^{\circ}C$. The BPs were mostly stable in a simulated body fluid (SBF) solution for 2 years. An indirect cytotoxicity test on natural HA ceramics showed no threat to the cells. Conclusions: In conclusion, the sintering temperature of $1,200^{\circ}C$ affected the microstructure, phase, and biological characteristics of natural HA ceramics consisting of calcium phosphate. The Ca-P-based natural ceramics are bioactive materials with good biocompatibility; our results indicate that the prepared HA ceramics have great potential for agricultural and biological applications.

• Research in Plant Disease
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• v.13 no.1
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• pp.57-60
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• 2007

A rhizopus soft rot caused by Rhizopus stolonifer occurred sporadically on grape in orchard in Gyeongsang-nam-do Agricultural Research and Extension Services and in Wholesale Market of Agricultural Products in Jinju city. The infected fruits were rapidly water-soaked, softened and eventually rotted, and the symptoms were initiated from wounds or cracks occurred at harvest time. Sporangiophores were $850{\sim}1,800{\mu}m$ in length and $12{\sim}23{\mu}m$ in width. Sporangia were globose or hemispheric and $80{\sim}190{\mu}m$ in size. The color of sporangia was white and cottony at first and gradually to brownish black, bearing abundant spores when it matured. Columella were hemispheric and $70{\sim}95{\mu}m$ in size. Sporangiospores were irregular round or oval, brownish-black streaked and $8{\sim}22{\times}6{\sim}10{\mu}m$ in size. The optimum temperature for mycelial growth of the fungus on PDA was 25$^{\circ}C$. On the basis of mycological characteristics and pathogenicity to grape (Vitis vinifera), the causal fungus was identified as Rhizopus stolonifer (Ehrenberg ex. Fr,) Lind. This is the first report of Rhizopus soft rot by R. stolonifer on grape (V. vinifera) in Korea.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.210-215
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• 2007

This study aims to investigate if the properly use of pesticide in Ginseng farmland at Gangwon-do, Korea. Questionnaire included 36 questions such as control method for plant diseases, pests and weeds and pattern of pesticide use was answered by 271 Ginseng farmers lived in 4 cities and 8 counties at Gangwon-do. Ginseng farmers have noxious plant diseases, insects and weeds such as leaf spot, anthracnose, snail, stem-mining fly, horseweed and hairy crabgrass. To control of these, 35% of farmers relied on various type of pesticides and 31.5% of farmers used pesticides mingling with natural enemy, microorganism and organic materials. Farmers selected the pesticide based on the their own experiences or by recommendation of market dealers and neighbors, resulting in the use of inappropriate pesticides in the Ginseng farmland(78.8 % ). They followed standard dosage of the pesticide from Handbook of Pesticide Application(96.3%). They, however, used the same pesticides from 2 to 5 years(44.1 %). This consecutive use of pesticide could be induced resistance. This survey resulted that study for pesticide resistance and systematic educational program for proper use and selection of pesticide to Gingseng farmers should be conducted in farmland at Gangwon-do, Korea.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.463-472
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• 2023

The insecticidal activities of 27 different commercial products with environmentally friendly organic material(EFOM) against Scotinophara lurida, a major rice pest, were evaluated in the laboratory using spraying methods on plants and insects. Seven plant-derived organic farming materials (EFOM-8, -10, -12, -13, -19, -20, and -26) with high insecticidal effects when sprayed directly on the insect's body rather than on the plant were selected. In the indoor rice pot test, all 7 EFOMs showed an insecticidal rate of over 73.3% under flooding conditions. Notably, EFOM-13 and EFOM-20 demonstrated much higher insecticidal rates, ranging from 1.5 to 1.8 times, in flooding conditions compared to drained conditions. In the semi-paddy field test, EFOM-10 (80% garlic extract), EFOM-13 (62% neem extract), and EFOM-26 (70% sophora extract+28% ethyl alcohol+2% pyrethrum extract) exhibited a higher control value of 88.9% in the irrigated paddy on the 7th day, surpassing the control values in the drained paddy by 1.4 to 1.9 times. The control value in the irrigated rice paddy field sprayed with EFOM-10 reached 86.2% on the 7th day, which was 1.4 times higher than 61.9% in the drained paddy. Taken together, the findings suggest that direct contact of the insect's body with sufficient amounts of spray solution and the maintenance of paddy irrigation can enhance the controlling effect of EFOMs. These findings will be valuable in developing an optimal S. lurida control strategy for application in rice paddy fields in the near future.

• Food Science and Preservation
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• v.24 no.6
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• pp.802-812
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• 2017

This study was conducted to investigate the quality properties depending on the cultivation methods (general, organic, pesticide-free) of yuza and its various parts (peel, pulp, seed). The contents of hesperidin were the highest in yuza feel grown by pesticide-free method (13.23 mg/g). The contents of naringin presented a higher content in the peel, especially which of the general (4.62 mg/g) showed the highest value. Vitamin C analysis showed the highest content in the peel, significantly varied according to the cultivation method and various parts (p<0.05). Vitamin C value was significantly highest in organic peel, which was 770.02 mg/100 g, whereas among the peel, the pulp and the seed were it the lowest in the seed. The content of total polyphenols were the highest in general peel (0.85 mg/g). Flavonoid content of pesticide-free seed was significantly higher than those of the other yuja samples which was 0.89 mg/g (p<0.05). The DPPH radical scavenging activity was relatively more active in the peel among the above-mentioned three parts, especially the pesticide-free peel was most active, which was 73.94%. The ABTS radical scavenging activity of organic peel was significantly active among the samples, which was 84.47% (p<0.05). Based on these results, it can be said that yuja has variety of useful components in the pulp and the seed as well as the peel: and thus it's hight recommended to develop more varied yuja products.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.3
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• pp.402-413
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• 2001

Food safety is a term broadly applied to food quality that may adversely affect human health. These include zoonotic diseases and acute and chronic effects of ingesting natural and human-made xenobiotics. There are two major areas of concern over the presence of residues of antibiotics in animal-derived foodstuffs with regard to human health. The first is allergic reactions. Some antibiotics, such as penicillins can evoke allergic reactions even though small amounts of them are ingested or exposed by parenteral routes. The second is development of antibiotic resistance in gut bacteria of human. Recently multi-resistant pneumococcal, glycopeptide-resistant enterococci and gram negative bacteria with extended-spectrum $\beta$-lactamases have spread all over the world, and are now a serious therapeutic problem in human. Although it is evident that drugs are required in the efficient production of meat, milk and eggs, their indiscriminate use should never be substituted for hygienic management of farm. Drug should be used only when they are required. In addition to veterinary drugs, environmental contaminants that were contaminated in feed, water and air can make residues in animal products. Mycotoxins, heavy metals, pesticides, herbicides and other chemicals derived from industries can be harmful both to animal and human health. Most of organic contaminants, such as dioxin, PCBs and DDT, and metals are persistent in environment and biological organisms and can be accumulated in fat and hard tissues. Some of them are suspected to have endocrine disrupting, carcinogenic, teratogenic, immunodepressive and nervous effects. The governmental agencies concerned make efforts to prevent residue problems; approval of drugs including withdrawal times of each preparation of drugs, establishment of tolerances, guidelines regarding drug use and sanitation enforcement of livestock products. National residue program is conducted to audit the status of the chemical residues in foods. Recently HACCP has been introduced to promote food safety from farm to table by reducing hazardous biological, chemical and physical factors. Animal Production Food Safety Program, Quality Assurance Programs, Food Animal Residue Avoidance Databank are para- or non-governmental activities ensuring food safety. This topic will cover classification and usage or sources of chemical residues, their adverse effects, and chemical residue status of some countries. Issues are expanded to residue detection methodologies, toxicological and pharmacokinetic backgrounds of MRL and withdrawal time establishments, and the importance of non-governmental activities with regard to reducing chemical residues in food.

• Analytical Science and Technology
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• v.28 no.3
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• pp.175-181
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• 2015

Cyantraniliprole, which is an ananthranilic diamide insecticide that was developed by the DuPont Corporation, was registered in the Republic of Korea in 2012. It offers exceptional insecticidal activity on a broad range of Lepidopera, Coleoptera, Diptera, and Isoptera. The maximum residue limits are set to pepper, peach, apple, sweet pepper, welsh onion, and so on (0.2~2.0 mg/kg). Therefore, an analytical method for determining cyantraniliprole residue in agricultural products was developed to ensure food safety. In previous studies, welsh onions were among vegetables included in the allium species, which is a representative plant with sulfur organic compounds. In this study, the analytical method was developed and evaluated for the elimination of sulfur compounds from the test solution of allium species during pesticide residue analysis. In order to inactivate the enzyme allinase and produce sulfur compounds, sample extraction was made in the base state pH 10 by reducing the activity of the enzyme. The recoveries of the developed method ranged from 81.9% to 83.2%, and the relative standard deviations were less than 10%. Therefore, based on the results, the method developed in this study is accurate and appropriate for use in cyantraniliprole determination. It will be used as the official method for managing the safety of cyantraniliprole residues in agricultural products.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.130-138
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• 1976

In order to utilize the agricultural waste products, two strains of mold producing powerful cellulolytic enzyme were sereened from various soils, composts, rotten wood and others. The optimum condition of cellulase production was studied. The results obtained were summarized as follows. 1. Two strains of mold which showed remarkably high cellulolytic activity were identified as Aspergillus niger-SM 6 and Trichoderma viride-SM 10. 2. The highest cellulase production was obtained at pH 5.0-6.0 in 5 days. 3. Cellulase production in strain Aspergillus niger-SM 6 increased with the addition of C.M.C., $(NH_4)_2SO_4$, C.S.L., orange peel powder and rice hull. The rice hull, treated with 3N NaOH at $120^{\circ}C$ for 15 min. and neutralized with various acids, was used. Up to 50% of wheat bran could be substituted by the treated rice hull without any decrease of cellulase activity. 4. In the strain of Trichoderma viride-SM 10, cellulase production increased with the addition of C.M.C., $NH_4NO_3$, Vitamin-free casamino acid and orange peel powder, while the other carbon, nitrogen, phosphate sources, natural nutrients and organic substances gave no remarkable effect.

• Journal of Life Science
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• v.30 no.12
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• pp.1128-1139
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• 2020

Over recent years, it has become evident that food and agricultural products are easily contaminated by fungi of Aspergillus, Fusarium, and Penicillium due to rapid climate change, which is not only a global food quality concern but also a serious health concern. Owing to consumers' interest in health, resistance to preservatives such as propionic acid and sorbic acid (which have been used in the past) is increasing, so it is necessary to develop a substitute from natural materials. In this review, the role of lactic acid bacteria as a biological method for controlling the growth and toxin production of fungi was examined. According to recent studies, lactic acid bacteria effectively inhibit the growth of fungi through various metabolites such as organic acids with low molecular weight, reuterin, proteinaceous compounds, hydroxy fatty acids, and phenol compounds. Lactic acid bacteria effectively reduced mycotoxin production by fungi via adsorption of mycotoxin with lactic acid bacteria cell surface components, degradation of fungal mycotoxin, and inhibition of mycotoxin production. Lactic acid bacteria could be regarded as a potential anti-fungal and anti-mycotoxigenic material in the prevention of fungal contamination of food and agricultural products because lactic acid bacteria produce various kinds of potent metabolic compounds with anti-fungal activities.