• Food Science and Preservation
• /
• v.24 no.6
• /
• pp.827-833
• /
• 2017

This study was investigated the effects of various commercial sanitizers on microbial characteristics in fresh-cut iceberg lettuce during storage. For screening sanitizer, lettuce was cut and dipped in chlorine water ($0.2ml{\cdot}L^{-1}$), solution of organic acids such as ascorbic acid, citric acid, acetic acid, mixture of ascorbic acid and acetic acid (1-6%), and solutions of commercial sanitizers such as Formula 4$^{TM}$ (1,3,4%), Fresh produce wash$^{TM}$ (1,3,4%), Cleancol$^{TM}$ (1%), Chitochol$^{TM}$ (1%) and Natural Ca$^{TM}$ (0.1%) for 3 min, respectively. Washing lettuce with selected sanitizers resulted in reduction of aerobic bacteria of more than 2 log CFU/g. Initial pH of lettuce was related with the pH of sanitizers. pH ranged from 4.7 to 6.1 in Formula 4 (4%, pH 1.7) and Natural Ca (0.1%, pH 12.0), respectively. Chlorine water showed consistent and significant inhibition effect in all of microorganisms except total coliform. Over 3% of Formula 4 and Fresh produce wash were found to have high bactericidal activity among sanitizers. The sanitizers of chlorine water, Fresh produce wash, Chitochol and Natural Ca were effective in reducing yeast and mould populations. As coliform and E. coli, Formula 4 (4%) showed the highest bactericidal activity. The bactericidal effect of commercial sanitizers during storage varied with the kinds and concentrations of tested sanitizers. Although inhibition effect was not showed during storage, these results suggest that commercial sanitizers could be an alternative to chlorine for washing fresh-cut produce.

• Korean Journal of Environmental Agriculture
• /
• v.6 no.2
• /
• pp.1-11
• /
• 1987

The degradation of two chemicals seem to be clearly affected by soil microbial activity in submerged soil $conditions(30{\pm}1^{\circ}C)$. The Active ingredient of Diazinon disappeared about 5 times faster than that of Dursban. By Applying 300% higher concentrations of both chemicals. under the above soil conditions, however, degradation was retarded by about one day. Some of the metabolites of Diazinon were as follows: 0.0-diethyl phosphorothioate and sulfotep as hydrolytic products, and diazoxon, 0.0-diethyl-0-[2-(1-hydroxy-1, 1-dimethyl)-6-methyl]-pyrimidinyl phosphorothioate and 2-isopropyl-6-methyl-pyrimidine-4-one as degradation products of monooxygenase. But 0. 0-diethyl phosphorothioate was the only methabolite of Dursban.

• Korean Journal of Environmental Agriculture
• /
• v.25 no.1
• /
• pp.85-92
• /
• 2006

Fungicides including keroxym-methyl (strobilurin fungicide), fenarimol and trifulmizole (DMI, boscalid (anilide) and metrafenone (benzophenone) were evaluated for preventive and curative efficacies against powdery mildew on oriental melon. The fungicides were applied preventatively at 7 days, 3 days and 3 hours before inoculation. Curative applications were made by applying fungicides three times at the interval of one week when infected leaves by powdery mildew were about 16% or 30%. Then preventative and curative efficacies were evaluated one week after inoculation and final application, respectively. Boscalid and metrafenone showed preventive efficacies of 74.3 and 68.3% against powdery mildew development respectively, when treated at 7 days before inoculation. They showed 89.4 and 87.2% efficacies when treated at 3 days before iniculation and 98.5 and 93.2% at 3 hours before inoculation respectively. However, there were no preventive efficacies in kresoxym-methyl, triflumizole and femarimol (DMI fungicides) when trebled at both 7 and 3 days before inoculation. At the preventive treatment 3 hours before inoculation, they indicated 59.0, 42.5, and 37.2% efficacies, respectively. When leaves were infected about 30% by powdery mildew, curative application of boscalid and metrafenone showed 85.9 and 74.0% of efficacies, respectively. Curative efficacies of kresoxym-methyl, tiflumizole and fernarimol were 5.5, 23.0 and 46.7% respectively. When leaves were infected about 16%, curative application of boscalid and metrafenone showed 100 and 97.5% of efficacies, respectively. However, the triflumizole and fernarimol showed relatively low curative efficacies of 30.8 and 51.6%, respectively. Microscopic observation of mycelial growth and conidia formation after detection of powdery mildew disease indicated lysis of mycelium and these lysis suppression of conidia formation showed tendency in accordance with curative efficacies of fungicides.

• The Korean Journal of Pesticide Science
• /
• v.10 no.1
• /
• pp.36-42
• /
• 2006

For the effective control of pepper anthracnose, in vitro antifungal activities of 13 commercial fungicides were tested on spore germination, mycelial growth, and sporulation of Colletotrichum gloeosporioides, anthracnose fungus. Among them, captan, chlorothalonil, dithianon, fluazinam and folpet completely inhibited the spore germination of C. gloeosporioides at the concentration of 0.8 ${\mu}g/ml$. They were followed by mancozeb and propineb, showing more than 80% inhibition of spore germination at 20 ${\mu}g/ml$. The mycelial growth of C. gloeosporioides was strongly inhibited by fluazinam and nuarimol. Except for nuarimol, most of the fungicides represented more antifungal activity on the spore germination than the mycelial growth of C. gloeosporioides. Azoxystrobin and metominostrobin, Strobilurin fungicides, were only moderately active against the spore germination and the mycelial growth of C. gloeosporioides, but they were effective antisporulant against C. gloeosporioides. From these results, control of pepper anthracnose will have achieved by preventive spray of the commercial fungicides.

• Korean Journal of Food Science and Technology
• /
• v.37 no.5
• /
• pp.838-843
• /
• 2005

Bacterial suspension test was used to establish Standardization Test Method to investigate bactericidal activity of disinfectant/sanitizer product. Using acceptable verification methodology, test substance showing 5 log or higher reduction in viable count against Escherichia coli ATCC 10536 and Staphylococcus aureus ATCC 6538, representing Gram-negative and -positive bacteria, respectively, under test conditions for $5\;min{\pm}10\;sec\;at\;20{\pm}1^{\circ}C$ was considered to have sanitizing capability. All disinfectant/sanitizer products tested under manufacturer's recommended in-use condition gave good reduction values against major food-poisoning bacteria. This standardized method was valuable for evaluating efficacy of disinfectants/sanitizers and could be used as Standardization Test Method for assessing bactericidal activity

• Research in Plant Disease
• /
• v.19 no.1
• /
• pp.7-11
• /
• 2013

Forty eight isolates of Botrytis elliptica and 23 isolates of B. cinerea from several locations in Korea were tested for resistance to fungicides used in the farmer's fields. Isolation frequency of B. elliptica having $EC_{50}$ (effective concentration of 50%) value $500-1000{\mu}g/ml$ to benomyl and mancozeb appeared highly, suggesting that the two fungicides are not effective in controlling leaf blight of lily in the field. The isolates were tested for resistance to fungicides procymidone and iprodione which were most commonly used in the farmer's fields. The rates of $EC_{50}$ value $5-50{\mu}g/ml$ to procymidome and iprodione were 93.7% and 100%, respectively, and those of $0-0.1{\mu}g/ml$ to diethofencarb+carbendazim and fludioxonil were 98.0% and 93.8%, respectively. In the rain-protected cultivation, control of leaf blight of lily was the most effective when iprodine, diethofencarb+carbendazim, and fludioxonil were sprayed alternately four times during the growing season.

• Research in Plant Disease
• /
• v.30 no.2
• /
• pp.131-138
• /
• 2024

The effects of five fungicides on the spore growth phase of Alternaria dauci, which causes carrot leaf blight, were tested using the spore viability assay (SVA) and agar dilution method (ADM). The average EC₅₀ values for chlorothalonil against seven isolates of A. dauci examined by SVA and ADM were 14.21 ㎍/ml and more than 100 ㎍/ml. Dithianon and folpet also had lower EC₅₀ values in SVA than in ADM, while iminoctadine trisalbesilate had lower EC₅₀ value in ADM. For fluazinam, the EC₅₀ values of SVA and ADM were 1.63 and 2.40 ㎍/ml, respectively. As EC₅₀ values of five fungicides according to the spore growth phase of A. dauci KACC 42997, the efficacy of each fungicide as chlorothalonil, dithianon, and folpet decreased when treated after spore germination rather than when treated with spores before germination. However, iminoctadine tris-albesilate was more effective when treated after spores germinated than when treated before treatment. The excellent effect of fluazinam on the pathogen was maintained until A. dauci KACC 42997 was cultured in potato dextrose broth for 6 hr and the germ tube grew beyond the size of the spore. However, when treated with iminoctadine tris-albesilate and fluazinam after culturing for 12 hr, as the EC₅₀ values of the two fungicides increased to 8.87 and 20.65 ㎍/ml, their efficacies decreased. The results of this study show that the treatment time of the fungicide should be determined by considering the effect of the fungicide on the spore growth phase of pathogens.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.9
• /
• pp.1265-1270
• /
• 2009

Pathogens contaminated on the surface of utensils could contribute to the occurrence of outbreaks due to cross-contamination to foods during the food preparation process. Therefore, the efficacy of chemical sanitizers (chlorine-based and alcohol-based commercial sanitizers) and dry-heat ($71^{\circ}C$) on inhibiting biofilms of five foodborne pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus) on the surface of stainless steel and polypropylene were investigated in this study. Initial populations of pathogens were 8.8$\sim$9.3 and 9.4$\sim$10.3 log CFU/coupon on the surface of stainless steel and polypropylene coupon, respectively, and these populations were not significantly reduced when they were treated with water for 5 min at room temperature. Treatments with chlorine sanitizer and dry-heat were not effective on inactivating pathogens on the surfaces of stainless steel and polypropylene. In contrast, treatments with alcohol sanitizer were very effective on inactivating pathogens on the surfaced of stainless steel and polypropylene. Reduction levels ranged from 3.4 to 6.4 log and from 5.5 to 7.4 log CFU/coupon in stainless steel and plastic coupons, respectively. From these results, alcohol-based sanitizer could be used as a potential way for controlling microbial contamination on the surface of utensils, cooking equipment, and other related environments.

• Journal of Food Hygiene and Safety
• /
• v.31 no.4
• /
• pp.299-303
• /
• 2016

Salmonella spp. and Brucella spp. can cause considerable diseases on both humans and animals. In addition, these microorganisms cause the economic loss in animal farming and food industry. In this study, the disinfection efficacy of a disinfectant spray, composed to grapefruit seed extract, citric acid, malic acid and benzalkonium chloride, was evaluated against S. Typhimurium and B. ovis. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test bacteria for 30 min at $4^{\circ}C$. The disinfectant and test bacteria were diluted with hard water (HW) or organic matter suspension (OM) according to treatment condition. On HW condition, the bactericidal activity of the disinfectant spray against S. Typhimurium and B. ovis was 5 and 4 fold dilutions, respectively. On OM condition, the bactericidal activity of the disinfectant spray was 2 and 1 fold dilutions against S. Typhimurium and B. ovis, respectively. As the disinfectant spray possesses bactericidal efficacy against foodborne pathogens such as S. Typhimurium and B. ovis, the disinfectant spray can be used to control the spread of bacterial diseases.

• Research in Plant Disease
• /
• v.26 no.2
• /
• pp.61-71
• /
• 2020

With 32 fungicides, it was examined the inhibitory effects on the mycelial growth of Alternaria dauci KACC42997 causing Alternaria leaf blight of carrot. Showing the results of the agar dilution method, the fungicides belonging to C2, C5, G1, E2, and E3 group were excellent in inhibiting mycelial growth. Protective fungicides belonging to M group, except for iminoctadine tris-albesilate, and pyraclostrobin belonging to C3 group were effective in inhibiting spore germination of pathogens. The fungicides included into C2 group inhibiting succinate dehydrogenase activity and the G1 group inhibiting demethylase activity showed the excellent inhibitory effect on mycelial growth but the inhibitory effect of spore germination was very low. However, fluazinam belonging to C5 group was excellent in inhibiting spore germination as well as mycelial growth. Especially, when 100 ㎍/ml of fluxapyroxad belonging to the C2 group was treated, 47.1% of spore formation was inhibited on the medium. In comparison of the resistance factors of 3 fungicide groups, as G, C, and E group, in populations of A. dauci isolates collected from Gumi, Pyeongchang, and Jeju, resistance factor in the population of Jeju was the lowest. However, two isolates resistant to fludioxonil belonging to E2 group were found in the isolate group of Pyeongchang, and both showed cross-resistance to iprodione and procymidone.