• Journal of Food Hygiene and Safety
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• v.27 no.1
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• pp.103-107
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• 2012

We compared between an automated most-probable-number technique $TEMPO^{(R)}$TVC and traditional plating methods $Petrifilm^{TM}$ for estimating populations of total aerobic bacteria in various livestock products. 257 samples randomly selected in local retail stores and 87 samples inoculated with $E.$ $coli$ ATCC 25922, $Staphylococcus$ $aureus$ ATCC 12868 were tested in this study. The degree of agreement was estimated according to the CCFRA (Campden and Chorleywood Food Research Association Group) Guideline 29 and the agreement indicates the difference of two kinds methods is lower than 1 log base 10($log_{10}$). The samples of hams, jerky products, ground meat products, milks, ice creams, infant formulas, and egg heat formed products were showed above 95% in the agreement of methods. In contrast, proportion of agreement on meat extract products, cheeses and sausages were 93.1%, 92.1%, 89.1%, respectively. One press ham and five sausages containing spice and seasoning, two pork cutlets containing spice and bread crumbs, two meat extract product and two natural cheeses and one processing cheese with a high fat content, and one ice cream containing chocolate of all samples showed the discrepancy. Our result suggest that $TEMPO^{(R)}$TVC system is efficient to analyses total aerobic bacteria to compare manual method in time-consuming and laborious process except livestock products having limit of detection.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.871-876
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• 2010

Seven native and four introduced herbs namely $Thymus$ $quinquecostatus$, $Chrysanthemum$ $zawadskii$ var. $latilobum$, $Rosmarinus$ $officinalis$, etc. were selected for analysis of the DPPH radical scavenging and anti-microbial activity of their extracts. These perennial herbs are classified as $Labiatae$ and $Compositae$ except for $Saururus$ $chinensis$ and can be propagated through seedling and cuttage. These edible herbs are used as medicinal as well as ornamental plants. Their extract has electron donating ability which ranges from 69.7 to 78.7% for native herbs and 67.4 to 75.4% for introduced herbs. Native herbs have higher (3.54%) average DPPH radical scavenging than introduced herbs. In native herbs, maximum DPPH radical scavenging activity was observed in $Agastache$ $rugosa$ (78.7%) followed by $Saururus$ $chinensis$ while $Chamaemelum$ $nobile$ showed highest activity among the introduced herbs. Many herbs viz. $Saururus$ $chinensis$, $Chrysanthemum$ $zawadskii$ var. $latilobum$ and $Solidago$ $virga-aurea$ var. $gigantean$ showed excellent anti-microbial activity against gram positive $Enterococcus$ $faecalis$, maximum (80.0%) by $Saururus$ $chinensis$. Other herbs viz. $Solidago$ $virga-aurea$ var. $gigantea$, $Chrysanthemum$ $zawadskii$ var. $latilobum$, $Salvia$Salvia $plebeia$, $Chrysanthemum$ $indicum$, $Rosmarinus$ $officinalis$, $Chamaemelum$ $nobile$ and $Lavandula$ $stoechas$ showed anti-microbial activity against gram negative $Citrobacter$ $freundii$. Especially, the inhibition of colony growth of $Citrobacter$ $freundii$ was highest in the extract of $Chrysanthemum$ $zawadskii$ var. $latilobum$, and $Chamaemelum$ $nobile$.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.367-375
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• 2010

The bacteriological and physiochemical analysis of sea water and sediments in Tongyeong harbor was conducted to evaluate sanitary conditions. The samples were collected at 8 stations established once a month from June, 2008 to May, 2009. During the study period, the range of temperature was from 6.7 to $25.2^{\circ}C$, transparency ranged from 1.2 to 2.6 m, chemical oxygen demand ranged from 1.90 to 2.92 mg/L, dissolved oxygen ranged from 6.2 to 10.5 mg/L, dissolved nitrogen ranged from 0.052 to 0.098 mg/L, phosphate ranged from 0.044 to 0.065 mg/L, respectively. Seafood, if eaten raw, carries the risk of food poisoning. Seafood poisoning is often cause by pathogenic microorganism originating from fecal contamination, such as Salmonella sp., Shigella sp. and norovirus. Fecal coliforms are an important indicator of fecal contamination. Therefore, data on fecal coliform are very important for evaluating the safety of fisheries in coastal areas. So, we investigated the sanitary indicate bacteria. The coliform group and fecal coliform MPN's of sea water in Tongyeong harbor were ranged from < 1.8~22,000/100 mL (GM 164.9 MPN/100 mL) and < 1.8~7,900 MPN/100 mL (GM 33.7 MPN/100 mL), respectively. Total coliform were detected 97.0% in 96 of samples and 68.9% of total coliforms were fecal coliforms. These results similar to another seawater detection ratio of total coloforms and fecal coliforms. The Vibrios was isolated and identified with VITEK system. Four hundred eighty strains that were obtained from sea water samples in Tongyeong harbor Detection ratio Vibrio alginolyticus, 34.2%, Vibrio parahaemolyticus, 13.8%, Vibrio vulnificus 10.0%, and V. mimicus 12.5% respectively. Vibrio cholerae O1, was not detected. During the study period, the ranges of water content, ignition loss, COD, and acid volatile sulfates in sediments in Tongyeoung harbor were 41.0~57.4%, 7.8~10.5%, 6.51~9.30 mg/g, 0.04~0.09 mg/g, respectively. Heavy metals in sediment of Tongyeoung harbor were Cd, $0.10{\pm}0.05$; Cu, $4.79{\pm}8.20$; As, $1.95{\pm}0.17$; Hg, $0.10{\pm}0.07$; $Cr^{6+}$, $0.34{\pm}0.12$; Zn, $125.33{\pm}16.40$; Ni, $16.43{\pm}1.93$ mg/kg.

• Food Science of Animal Resources
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• v.28 no.5
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• pp.610-615
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• 2008

This experiment was conducted to investigate the effects of drinking of Rhus tree-extract on laying performance and egg quality in hens. Four hundred eighty, 55-wk-old ISA brown, laying hens were divided into six groups, control, Rhus tree-extract 500 ppm, 1,000 ppm, 2,000 ppm, 3,000 ppm and 5,000 ppm. The hens were fed a supplemented drink containing Rhus tree-extract for 12 weeks. Egg production and egg mass increased by drinking Rhus tree-extract (p<0.05) and the feed conversion ratio also improved in Rhus tree-extract groups. Cecal numbers of Lactobacillus spp., E. coli and Salmonella were not different in treatments. Availability of protein and ash improved in the Rhus extract groups. The eggshell breaking strength and egg shell thickness were significantly increased in Rhus tree-extract 3,000 ppm and Rhus tree-extract 2,000 ppm groups compared to the other groups. Also, egg yolk color and Haugh unit were significantly improved by the dietary Rhus tree-extract (p<0.05).

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.22-30
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• 1982

Water quality of downstream of the Nagdong river, using for agricultural irrigation of the Gimhae plain, were observed. Water temperature, turbidity, residue, pH, BOD, COD, DO, hardness, chloride, sulphate, phosphate, inorganic nitrogenous compounds, sodium, general bacteria, E. coli and heavy metals of the water were investigated at Daejeo, Sikman, Bongrim, Noksan, Machal and Jangyou pumping stations in the Gimhae plain in May, July and October, 1981. The results obtained were as follows; 1) Average value of analyzed components of the water at all sampling sites were 7.8 pH, 6.3 ppm BOD, 6.5 ppm COD, 6.4 ppm DO, 231 ppm hardness, 582 ppm Cl-, 412 ppm $SO_4--$, 2.32 ppm $PO_4---$, 3.8 ppm $NH_4+,\;478\;ppm\;Na+$, 2964 No. /100 ml total coliform, 0.0040 ppm Cd, 0.0066 ppm Pb, respectively. 2) The most heavily polluted site of all investigated ones was Sikman. It seemed to be caused by the vast quantity of wastewater discharged from industrial district in Gimhae city. The next polluted sites were Bongrim, Daejeo and Noksan, and comparatively less polluted sites were Machal and Jangyou, judging from both appearance and physicochemical observation. 3) At Sikman, the most heavily polluted site, average value of components were 8.0 pH, 8.1 ppm BOD, 8.2 ppm COD. These values were close to the limit point of agricultural water quality standard of 8.0 ppm BOD (COD). 4) Any apparent variation was not observed by the sampling season in most components except DO and $NH_4+$. DO of October was higher than that of May or July but $NH_4+$ was low. 5) $NH_4+$ content was comparatively high in downstream of the Nagdong river of which water is used as the agricultural irrigation in the Gimhae plain. Therefore, fertilizer application on the farming land must make account of nitrogen content of the irrigation water 6) It was considered that chloride and sodium contents would not influence the crop cultivation in common season, but in dry season irrigation must be done carefully.

• Korean Journal of Food Science and Technology
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• v.26 no.2
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• pp.188-194
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• 1994

The inhibitory effects of rice extract on mutagenicity induced by 3-amino-1,4-dimethyl-5H-pyrido [4,3-b]indole(Trp-P-1), 3-amino-1-methyl-5H-pyrido [4,3-b]indole(Trp-P-2), sodium azide(SA), 2-nitrofluorene(2NF), mitomycin C(MMC), aflatoxin $B_1(AFB_1)$ and 4-nitroquinoline oxide(4-NQO) were investigated using Salmonella typhimurium reversion assay, SOS chromotest and spore rec-assay. In Salmonella typhimurium reversion assay, methanol extract from brown rice (Illpumbyeo, Japonica variety) showed the highest inhibitory effect among other extracting solvent including hexane, chloroform and water. Methanol extract showed stronger inhibitory effect, above 85%, on indirect-acting mutagens(Trp-P-1, Trp-P-2 and $AFB_1$) than those on direct-acting mutagens(4-NQO, 2NF). In SOS chromotest, methanol extracts showed $77.6{\sim}88.9%$ effects on SOS function induced by Trp-P-1, Trp-P-2, $AFB_1$ and 4-NQO. In spore rec-assay, methanol extracts inhibited the mutagenicity induced by $AFB_1$ and MMC. As the concentration of methanol extract increased, inhibitory effect on mutagenicity increased but reached at steady state as inhibition rate of 90% when the concentration was above 5 mg/plate. In inhibitory effects of methanol extracts by various rice varieties, all of 11 varieties turned out to have inhibitory effect on mutagenicity. There was no significant difference (p>0.05) in inhibitory effect of methanol extracts between brown and white rice against Trp-P-1, but showed difference (p<0.05) against 4-NQO.

• Journal of Bio-Environment Control
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• v.29 no.3
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• pp.239-244
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• 2020

Effect of 6kg large unit with the carton box (20% open ratio) and MA box (10,000cc·m^-2·day^-1·atm^-1 oxygen transmission rates modified atmosphere package), and the 100g small unit with MA film on asparagus sensory quality were evaluated. The CO₂ concentration depended largely on the packing unit and maintained at around 3% in small MA packages, whereas in the MA box increased to 12%. Ethylene concentration rapidly increased until after 3 days of storage in MA packages and then decreased to maintain 5μL·L^-1. Unrelated to the unit size, the lower weight loss was obtained in MA packages. A significant difference in visual quality was shown since the 15th day, the best and worst were the MA box and small MA package on the finish day. Off-odor was the highest in small MA packages and the lowest in the carton box (< 3.0). Although there was no significant difference in firmness among all treatments, the packages showed the highest firmness in tips and stems, respectively. The sugar content and hue angle decreased during storage, but there was no statistical difference in all treatments. EL was lowest and highest in small MA package and carton box, respectively. On the 10th day, the total aerobic bacteria was lowest in small MA packages, but no significant difference on the 20th day. E. coli was not found in all treatments on the 10th day, while it was the lowest in the MA box on the 20th day. The mold and yeast were not observed during the whole storage. Based on the above results, the carton box packaged with 10,000cc OTR film was more effective in maintaining the quality of green asparagus with the suitable CO₂ concentration for asparagus cold storage.

• Food Science and Preservation
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• v.24 no.5
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• pp.565-575
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• 2017

This study was carried out to investigate shelf-life and quality of fresh-cut Dungkunma (Dioscorea bulbifera) in order to elevate utilization of Dungkunma a fresh food. Before vacuum-packaging (in polyethylene/polypropylene film ($100{\mu}m$, $15{\times}20cm$, $75{\pm}2cmHg$) and storaging at $2^{\circ}C$, Dungkunma was peeled out and cut to dice type ($2.0{\pm}0.5cm^3$), and then washed and blanched using hot water (at $90{\pm}2^{\circ}C$ with 2% NaCl solution for 30 sec). Blanched Dungkunma was pre-dried at room temperature, $40^{\circ}C$ and $50^{\circ}C$ for removing surface water. Each peeled dice Dungkunma was packed 50 g in polyethylene/polypropylene film ($100{\mu}m$, $15{\times}20cm$) with vacuum treatment ($75{\pm}2cmHg$) and stored at $2^{\circ}C$ for 90 days. Hardness and adhesiveness of Dungkunma blanched by 2% NaCl and pre-dried at $50^{\circ}C$ (SB50) were the highest, but changes were the least during storage. Lightness and yellowness of stored Dungkunma in all treatments decreased slightly while redness increased during storage. Changes of color of SB50 was the least. Total concentration of aerobic bacteria in SB50 was $1.88{\pm}0.18log\;CFU/g$ during 90 days and E. coli was detected in all treatments during whole storage periods. Dioscin and allantoin contents of SB50 were virtually unchanged during the storage. Consequently, the results of this study suggest that vacuum packaged Dungkunma after blanching using 2% NaCl solution could be effective to prolong the quality of fresh-cut Dungkunma.

• Food Science and Preservation
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• v.24 no.5
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• pp.707-713
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• 2017

The objective of this study was to select yogurt starter from Korean traditional fermented foods. The 2 strains (KM24, KM32) among 50 strains of isolated lactic acid bacteria selected as starter based on milk clotting ability, antimicrobial activity against various pathogens, tolerance in artificial gastric and bile juice and growth in 10 % skimmed milk. The strains were identified as Lacobacillus plantarum (KM32) and Pediococcus pentosacesus (KM24) by 16S rRNA gene sequencing. Viable cell number of yogurt fermented with mixed strains (KM24 and KM32) was 9.66 log CFU/mL after fermentation for 48 h and maintained $10^9CFU/mL$ during fermentation for 72 h at $37^{\circ}C$. The pH and titratable acidity of mixed cultured yogurt were 4.25% and 0.83% after fermentation for 48 h at $37^{\circ}C$, respectively. The physico-chemical characteristics of mixed cultured yogurt after fermentation for 48 h were $38.45{\mu}g/mL$ (polyphenol content), 48.57% (DPPH radical scavenging activity) and 465.40 cp (viscosity), respectively. The mixed cultured yogurt maintained $10^9CFU/mL$ of lactic acid bacteria during storage 10 days at $4^{\circ}C$. The viable cell number of yogurt prepared with mixed culture(KM32+KM24) maintained higher and than that of control (L. casei) during storage. These results indicated the potential use of selected strains (KM32+KM24) isolated from kimchi as a yogurt starter with strong acid tolerance and probiotics properties.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.202-209
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• 2014

RNA interference (RNAi) is the method which controls phenotypes of gene in live cells. Chitinase is the enzyme helping digestion and absorption of old cuticles during the ecdysis of insects. In order to investigate molting-inhibition effect with the chitinase related gene in Spodoptera litura, RNA was extracted from the $5^{th}$ instars. cDNA was synthesized and then we obtained about 700 bp size chitinase. After PCR products were cloned into a pGEM T-easy vector, colonies were picked. DNA was extracted from the colony cultures. EcoR I enzyme was used to check whether PCR products were inserted or not. And then we confirmed vector band of about 3 kb and insert band of about 700 bp. To synthesize the dsRNA, each DNA was cut with Spe I and Nco I enzymes (Circular DNA became lineared DNA). After synthesis of dsRNA, approximately 5 ul dsRNA was injected into the $3^{rd}$ abdominal segment of S. litura $4^{th}$ larvae. The concentration of dsRNA was about $10{\mu}g/{\mu}l$. We confirmed larval-larval molting : there were phenotypically abnormal individuals - for instance malformation, molting inhibition and change of integument color. Pupaadult molting : there were phenotypically abnormal individuals - for instance molting inhibition, change of wings and malformation. Also we could investigate the pupation, emergence and variation about noninjection, treated with DW and dsRNA. Each pupation was non-injection 83.3%, DW 78.3% and dsRNA 66.7%. Each emergence was non-injection 90.0%, DW 72.3% and dsRNA 65.0%. So we considered that chitinase dsRNA induced molting inhibition effect. But each variation was non-injection 8.9%, DW 2.9% and dsRNA 19.2%. Therefore dsRNA group showed the highest variation value. When 18 hours after injecting dsRNA, we could obtain abnormal individual.