• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2159-2170
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• 2016

Many plant-pathogenic bacteria are dependent on quorum sensing (QS) to evoke disease. In this study, the population of QS and quorum quenching (QQ) bacteria was analyzed in a consecutive monoculture system of Pseudostellaria heterophylla. The isolated QS strains were identified as Serratia marcescens with SwrIR-type QS system and exhibited a significant increase over the years of monoculture. Only one QQ strain was isolated from newly planted soil sample and was identified as Bacillus thuringiensis, which secreted lactonase to degrade QS signal molecules. Inoculation of S. marcescens to P. heterophylla root could rapidly cause wilt disease, which was alleviated by B. thuringiensis. Furthermore, the expression of lactonase encoded by the aiiA gene in S. marcescens resulted in reduction of its pathogenicity, implying that the toxic effect of S. marcescens on the seedlings was QS-regulated. Meanwhile, excess lactonase in S. marcescens led to reduction in antibacterial substances, exoenzymes, and swarming motility, which might contribute to pathogensis on the seedlings. Root exudates and root tuber extracts of P. heterophylla significantly promoted the growth of S. marcescens, whereas a slight increase of B. thuringiensis was observed in both samples. These results demonstrated that QS-regulated behaviors in S. marcescens mediated by root exudates played an important role in replanting diseases of P. heterophylla.

• Journal of Mushroom
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• v.18 no.1
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• pp.107-114
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• 2020

Fifteen species of wild mushrooms, which are classified as edible, medicinal, poisonous, or unknown types, were analyzed for their free amino acid contents. The average total amino acid content was 1,120.0 mg/kg in the edible type, 1,037.8 mg/kg in the medicinal type, and 1,010.8 mg/kg in the poisonous or unknown type, respectively. The edible type wild mushrooms showed the highest average content of total essential amino acids; conversely, the poisonous or unknown type showed the lowest content. Leucopaxillus giganteus (OK811) showed the highest total amino acid (1,212.4 mg/kg) and essential amino acid (490.2 mg/kg) contents among edible type, while Pycnoporus sanguineus (OK1071) showed the highest total amino acid (1,233.7 mg/kg) and essential amino acid (412.8 mg/kg) contents among the medicinal type. Among the poisonous or unknown type, Hypholoma fasciculare (OK826) showed the highest total amino acid (1,223.4 mg/kg) and essential amino acid (442.8 mg/kg) contents. The amino acid contents of wild mushrooms are fundamental data for the screening of useful genetic resources with nutritionally superior properties.

• Food Science and Preservation
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• v.12 no.1
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• pp.80-85
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• 2005

The effect of 12 edible mushroom species on the antioxidant and cytotoxicity on cancer cells were studied Methanol extract of Lyophyllum ulmarium, Cordyceps militaris and Sarcodon aspratus showed $30\~60\%$ DPPH radical scavenging activity and $39\~53\%$ protective effects against the cytotoxicity of $B_2O_2$. Methanol extracts of Sarcodon aspratus, Lyophyllum ulmarium, Cordyceps militaris, Agaricus blazei and Ganoderma lucidum revealed high inhibitive activities in cytotoxicity on human leukemia tells such as promyelocytic leukemia cell (HL60) and histiocytic lymphoma cell (U937). Highest toxicity was observed against HL60 cells in Sarcodon aspratus methanol extract showing $70.5\%$ inhibition at 1mg/mL whereas Cordyceps militaris methanol extract showed $81.5\%$ inhibition against U937 cells. Most water extracts of edible mushrooms exhibited the lowest effect against HL60 and U937 cells compared to methanol extract. These extract did not show cytotoxic effects against human lymphocyte. Results revealed 5 kinds of edible murshroom (Cordyceps militaris, Agaricus blaxei, Lyophyllum ulmarium, Ganoderma lucidum and Sarcodon aspratus) have strong antioxidative and in vitro anticancer efforts.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.641-647
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• 1997

Volatile flavor components in whole edible portion, stem and leaf of fresh angelica (Angelica keiskei Koidz) were extracted by SDE (simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether (1:1, v/v) as an extract solvent and analyzed by GC-FID and GC/MS. Identification of the volatile flavor components in aroma concentrate was mostly based on the RI of GC and mass spectrum of GC/MS. Twenty five hydrocarbons, 15 alcohols, 3 aldehydes, 6 esters, 2 ketones and 1 acid were identified in the whole edible portion of angelica. Twenty hydrocarbons, 13 alcohols, 4 esters and 1 acid were identified in the stem sample of angelica. Nineteen hydrocarbons, 11 alcohols, 4 aldehydes, 6 esters, 2 ketones and 1 acid were identified in the leaf sample of angelica. ${\gamma}-Terpinene$, germacrene B, ${\delta}-3-carene$, cis-3-hexen-1-ol, ${\gamma}-muurolene$ and ${\gamma}-elemene$ were the main components in each edible portions of angelica. The terpenoid compounds in volatile flavor components identified from whole edible portion, stem and leaf samples were confirmed as 75.76%, 86.42% and 78.21%, respectively. These results suggest that terpenoid compounds have a great effect on the flavor characteristics of angelica.

• Food Science and Preservation
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• v.14 no.5
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• pp.439-444
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• 2007

This study was carried out to analyze the quality change of salted mackeral treated with extracts of edible plan(Diospyros kaki, Teucerium veronicoides and Zanthoxylum schinifolium) during storage for develope of preparation methods and high quality of mackerel. The Hunter's color values of salted mackerel was not changed during strange. L, a and b value of salted mackerel teated with Korean herbal extracts was lower changed than those of control(mackerel not treated extracts of edible plants). Adhesiveness, and viscosity of salted mackerel was higher at $4^{\circ}C$ during storage than those at $25^{\circ}C$, and was higher in groups treated extects of edible plants at early storage than those in control group. Hardness was low in the salted mackerel treated extracts of edible plane and control group during storage. The salted mackerel treated Z. schinifolium extracts was the highest scores in sensory evaluation among groups.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.29-36
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• 2011

The present study was performed to investigate antioxidant activities of Korean edible wild extracts. In water and methanol extracts of edible wild plants, total polyphenol content of water and methanol extracts ranged 4.6~183.8 and 8.2~270.1 mg/g, respectively. Radical scavenging activity against DPPH and ABTS radicals was observed to be high in Lysimachia barystachys, Aceriphyllum rossii, Securinega suffruticosa, Sedum kamtschaticum, and Pedicularis resupinata. Pedicularis resupinata, Securinega suffruticosa, Patrinia villosa, and Solidago virga-aurea var. asiatica showed effective SOD-like activity. There was significant correlation between polyphenol content and DPPH and ABTS radical scavenging activities, and SOD-like activity. Plant extracts such as Pedicularis resupinata, Securinega suffruticosa, Rhapontica uniflora, Lysimachia barystachys, and Aceriphyllum rossii had higher polyphenol content, radical scavenging, and SOD-like activity. These results indicate that Korean edible wild plants may be useful as potential antioxidant sources for improving human antioxidant defense system.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.470-473
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• 2008

A new kidney bean cultivar, "Hwanghyeob 2" was developed for edible pod kidney bean adaptable to Korean cultivation at the National Institute of Crop Science in 2005. "Hwanghyeob 2" was selected from a cross between KLG50073 and KLG50072. It has determinate growth habit, white flower, yellow pod color, oval shape of crossed section of pod at the harvesting time for edible pod. It has white seed coat and middle seed size (20.4 grams per 100 seeds). The average yield of edible pod of "Hwanghyeob 2" was 22.43 M/T per hectare in the yield trials which was carried out at the green house in spring and autumn in 2005. This yield level was 11 percent higher than that of the check cultivar "Kangnangkong 1".

• Journal of Food Hygiene and Safety
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• v.38 no.3
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• pp.89-98
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• 2023

Currently, no guidelines exist regarding the maximum residues of pesticides in edible oil which is a processed food commonly consumed in Korea. This lack of guidelines hinders the evaluation of the safety of edible oil in terms of pesticide contamination. In this study, an analysis method based on heat distillation and GC-MS/MS was established by optimizing the extraction and purification procedure for 68 pesticides. Important variables in the thermal distillation procedure included heating temperature and time, and we found the nitrogen flow rate as a mobile phase and the type of dissolving solvent were not considerably affected. The determination coefficient (R²) of the residual pesticide was 0.99 or higher, and the quantitative limit (LOQ) was 0.01-0.02 mg/L. The average recovery rate (n=5) was 66.1-120.0% and the relative standard deviation was lower than ±10% when 68 pesticides were spiked at concentrations of 0.01-0.02, 0.1, and 0.5 mg/L. In addition, the within-laboratory precision was less than ±11%, meeting the Korea Food and Drug Safety Evaluation Institute's Guidelines on Standard Procedures for Preparing Food Testing Methods (2016). Therefore, the test method developed in this study can be used as a test method for managing the safety of the residual pesticide concentration in edible oil.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1822-1831
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• 2015

This study was carried out to optimize coating process of the rice snack added with dried shrimp powder by using single extruder. A total of 8 independent variables were used for 4 independent variables of edible oil coating and 4 independent variables of seasoning coating. 4 independent variables for edible oil coating were set up as 10, 15, 20, 25 and 30% for the content of edible oil; 40, 50, 60, 70 and $80^{\circ}C$ for the tumbler temperature; 60, 70, 80, 90 and 100 rpm for the tumbler speed; 2, 3, 4, 5 and 6 min for the coating time. 4 independent variables for seasoning coating were set up as 2, 3, 4, 5 and 6% for the content of seasoning; 40, 50, 60, 70 and $80^{\circ}C$ for the tumbler temperature; 50, 60, 70, 80 and 90 rpm for the tumbler speed; 2, 3, 4, 5 and 6 min for the coating time. The characteristics of the dependent variables as coating yield and Breaking ratio of collet due to the condition changes of the independent variable was studied during process of edible oil coating and seasoning coating, respectively. As a results of this study, 20% of edible oil content, $70^{\circ}C$ of tumbler temperature, 80 rpm of tumbler speed, 4 min of coating time for process of edible oil coating, 3% of seasoning content, $60^{\circ}C$ of tumbler temperature, 70 rpm of tumbler speed, 3 min of coating time for process of seasoning coating were found to be the most preferable over other independent variables for the production of snack. In conclusion, it is necessary to set the independent variable in order to produce the high quality snack added with the rice as the main raw material and dried shrimp, edible oil and seasoning as the sub-materials.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.696-704
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• 2010

The objective of this study was analysis of two methods of land suitability classification for wild edible green. One method was Maximum limiting factor method (MLFM) and the other was Multi-regression method (MRM) for land suitability classification for wild edible green. The investigation was carried out in Pyeongchang, Hongcheong, Hoeingseong, and Yanggu regions in Korea. The obtained results showed that factors related to the decision classification of the land suitability for wild edible green cultivation were land slope, altitude, soil morphology and gravel contents so on. The classification of the best suitability soil for wild edible greens were fine loamy (silty), valley or fan of soil morphology, well drainage class, B-slope (2~7%), available soil depth deeper than 100cm, and altitude higher than 501m. Contribution of soil that influence to crop yields using Multi-regression method were slope 0.30, altitude 0.22, soil morphology 0.13, drainage classes 0.09, available soil depth 0.07, and soil texture 0.01 orders. Using MLFM, area of best suitable land was 0.2%, suitable soil 15.0%, possible soil 16.7%, and low productive soil 68.0% in Hongcheon region of Gangwon province. But, area of best suitable land was 35.1%, suitable soil 30.7%, possible soil 10.3%, and low productive soil 23.9% by MRM. There was big difference of suitable soil area between two methods (MLFM and MRM). When decision classificatin of the land suitability for wild edible green cultivation should consider enough analysis methods. Furthermore, to establishment of land suitability classification for crop would be better use MRM than MLFM.