• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.40-46
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• 2005

This study was performed to investigate the antimicrobial effects of the Citrus unshiu Markovich extracts against food-borne pathogens. First, the Citrus unshiu Markovich was extracted with methanol at room temperature, and fractionation of the methanol extracts from Citrus unshiu Markovich was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol. The antimicrobial activity of the Citrus unshiu Markovich extracts was determined using the paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of Citrus unshiu Markovich showed the highest antimicrobial activity against Bacillus cereus and Shigella sonnei. A synergistic effect was found in combined extracts of Citrus unshiu Markovich and Hedyotis diffusa Willd as compared to each extract alone. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Citrus unshiu Markovich against Bacillus cereus and Shigella sonnei. The ethyl acetate extract of Citrus unshiu Markovich showed strong antimicrobial activity against Bacillus cereus at the concentration of 5,000 ppm. The 5,000 ppm of ethyl acetate extract from Citrus unshiu Markovich retarded the growth of Bacillus cereus more than 24 hours and Shigella sonnei up to 24 hours. The ethyl acetate extracts of Citrus unshiu Markovich have shown an antimicrobial effect against Bacillus cereus and Shigella sonnei.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.23-29
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• 2005

To investigate potential characteristics of clay minerals (illite, kaolin, zeolite, vermiculite, and bentonite) for food industry application, antioxidative properties of clay minerals, electron-donating ability (EDA), peroxide value (POV), and thiobabituric acid (TBA) were measured, and antimicrobial activity against several food spoilage microorganisms were evaluated by minimum inhibition concentration (MIC) method. Changes in components by cooking clay minerals added to stored rice were measured by GC-MS. DPPH (1,1-diphenyl-2-picrylhydrazyl) analysis results revealed bentonite has strongest EDA at 20.6%. Antioxidant activities measured based on POV were similar to DPPH results. Induction period of linoleic acid with vermiculite was longest among. TBA results revealed zeolite hasstrongest antioxidant ability. Growth inhibition against E. coli and S. aureuswas observed in illite, vermiculite, and zeolite. Aroma components indicated decrease in hex anal, pent anal, non anal, linoleate, stearic acid, and oleic acid when clay minerals were added to stored rice. These results indicate that several clay minerals have antioxidative and antimicrobial abilities and improve flavor profiles in stored rice.

• The Korean Journal of Food And Nutrition
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• v.18 no.1
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• pp.81-87
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• 2005

This study was performed to investigate the antimicrobial activities of the Plagiorhegama dubium extracts against food-borne pathogens. The methanol extract was partitioned into petroleum ether, chloroform, ethyl acetate, and methanol portions. The antimicrobial activity of the P. dubium extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extracts of P. dubium showed the highest antimicrobial activity against Staphylococcus aureus and Escherichia coli. The synergistic effect has been found in combined extracts of P. dubium and Hedyotis diffsa as compared to each extracts alone. Finally, the growth inhibition curve was determined using methanol extracts of P. dubium against S. aureus and E. coli. The methanol extract of P. dubium showed strong antimicrobial activity against S. aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate portion from P. dubium retarded the growth of S. aureus more than 36 hours and E. coli up to 60 hours. The methanol extracts of P. dubium has been shown the antimicrobial activity against S. aureus and E. coli.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1106-1111
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• 2004

This study was performed to investigate the antimicrobial effect of the Indigofera kirilowii extracts against food-borne pathogens. The Indigofera kirilowii was extracted with methanol at room temperature, and fractionation of the methanol extract from Indigofera kirilowii was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol, respectively. The antimicrobial activity of the Indigofera kirilowii extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extract of Indigo/era kirilowii showed the highest antimicrobial activity against Staphylococcus aureus and Shigella dysenteriae. The water extract of Indigofera kirilowii showed relatively low antimicrobial activity against microorganisms used in this experiment. The synergistic effect has been found in combined extracts of Indigofera kirilowii and Pulsatilla koreana as compared to each extract alone. The growth inhibition curve was determined using ethyl acetate extracts of Indigofera kirilowii against S. aureus and S. dysenteriae. The ethyl acetate extract of Indigofera kirilowii showed strong antimicrobial activity against S. aureus at the concentration of 4,000 ppm. The 4,000 ppm of ethyl acetate extract from Indigofera kirilowii retarded the growth of S. aureus more than 24 hours and S. dysenteriae up to 48 hours. This study showed the possibility of using ethyl acetate extract of Indigofera kirilowii as a material of food preservative.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.130-135
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• 2005

To investigate the antimicrobial effect of the Patrinia scabiosaefolia extracts against food-borne pathogens, we extracted the P. scabiosaefolia with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, ethyl acetate, and methanol, respectively. The antimicrobial activity of the P. scabiosaefolia extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The ethyl acetate extracts of P. scabiosaefolia showed the highest antimicrobial activity against Escherichia coli and Shigella sonnei. Synergistic effect in inhibition was observed when P. scabiosaefolia extract was mixed Forsythiae fructus extract as compared to each extracts alone. Finally, the growth inhibition curves were determined by using ethyl acetate extracts of P. scabiosaefolia against Staphylococcus epidermidis and Shigella sonnei. The ethyl acetate extract of P. scabiosaefolia had strong antimicrobial activity against S. sonnei at the concentration of 4,000 ppm. At this concentration, the growth of S. Sonnei was retarded more than 72 hours and up to 48 hours for S. epidermidis. These results suggest that the ethyl acetate extracts of P. scabiosaefolia can be used for the efficient material against the growth of S. epidermidis and S. sonnei.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1579-1585
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• 2016

Sugar esters are valuable compounds composed of various sugars and fatty acids that can be used as antibacterial agents and emulsifiers in toothpaste and canned foods. For example, fructose fatty acid esters suppress growth of Streptococcus mutans, a typical pathogenic bacterium causing dental caries. In this study, fructose laurate ester was chosen as a target material and was synthesized by a transesterification reaction using Candida antarctica lipase B. We performed a solvent screening experiment and found that a t-butanol/dimethyl sulfoxide mixture was the best solvent to dissolve fructose and methyl laurate. Fructose laurate was synthesized by transesterification of fructose (100 mM) with methyl laurate (30 mM) in t-butanol containing 20% dimethyl sulfoxide. The conversion yield was about 90%, which was calculated based on the quantity of methyl laurate using high-performance liquid chromatography. Fructose monolaurate (M_r 361) was detected in the reaction mixture by high-resolution mass spectrometry. The inhibitory effect of fructose laurate on growth of oral or food spoilage microorganisms, including S. mutans, Bacillus coagulans, and Geobacillus stearothermophilus, was evaluated.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.271-278
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• 2016

The main purpose of milk heat-treatment is to improve milk safety for consumer by destroying foodborne pathogens. Secondly, heat-treatment of milk is to increase maintaining milk quality by inactivating spoilage microorganisms and enzymes. Pasteurization is defined by the International Dairy Federation (IDF, 1986) as a process applied with the aim of avoiding public health hazards arising from pathogens associated with milk, by heat treatment which is consistent with minimal chemical, physical and organoleptic changes in the product. Milk pasteurization were adjusted to $63{\sim}65^{\circ}C$ for 30 minutes (Low temperature long time, LTLT) or $72{\sim}75^{\circ}C$ for 15 seconds (High temperature short time, HTST) to inactivate the pathogens such as Mycobacterium bovis, the organism responsible for tuberculosis. Ultra-high temperature processing (UHT) sterilizes food by heating it above $135^{\circ}C$ ($275^{\circ}F$) - the temperature required to destroy the all microorganisms and spores in milk - for few seconds. The first LTLT system (batch pasteurization) was introduced in Germany in 1895 and in the USA in 1907. Then, HTST continuous processes were developed between 1920 and 1927. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. At present, UHT is most commonly used in milk production.

• Fisheries and Aquatic Sciences
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• v.26 no.10
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• pp.593-604
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• 2023

Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

• Journal of Nutrition and Health
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• v.38 no.2
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• pp.112-116
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• 2005

This study was performed to investigate the antimicrobial effect of the Agrimonia pilosa Ledeb. extracts against food-borne pathogens. First, the Agrimonia pilosa Ledeb. was extracted with methanol at room temperatures, and fractionation of the methanol extracts from Agrimonia pilosa Ledeb. was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol respectively. The antimicrobial activity of the Agrimonia pilosa Ledeb. extracts was determined using a paper disc method against food-borne pathogens and food spoilage bacteria. The petroleum ether extracts of Agrimonia pilosa Ledeb. showed the highest antimicrobial activity against Pseudomonas aeruginosa. The synergistic effect has been found in combined extracts of Agrimonia pilosa Ledeb. and Perillae folium as compared to each extracts alone. Finally, the growth inhibition curve was determined using ethyl acetate extracts of Agrimonia pilosa Ledeb. against Bacillus Cereus and Salmonella Enteritidis. The petroleum ether extract of Agrimonia pilosa Ledeb. showed strong antimicrobial activity against Bacillus Cereus at the concentration of 4,000 ppm. The 4,000 ppm of petroleum ether extract from Agrimonia pilosa Ledeb. retarded the growth of Bacillus Cereus more than 24 hours and Salmonella Enteritidis up to 36 hours. The petroleum ether extracts of Agrimonia pilosa Ledeb. has been shown the antimicrobial effect against Bacillus Cereus and Salmonella Enteritidis. (Korean J Nutrition 38(2): 112～116, 2005)

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.107-112
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• 2005

This study was performed to investigate the antimicrobial effect of the Hedyotis diffusa extracts against food-borne pathogens. First, the Hedyotis diffusa was extracted with methanol at room temperature and the fractionation of the methanol extracts was carried out by using petroleum ether, chloroform, and ethyl acetate, and methanol respectively. The antimicrobial activity of the Hedyotis diffusa extracts was determined by using a paper disc method against food-borne pathogens and food spoilage bacteria. The methanol extracts of Hedyotis diffusa showed the highest antimicrobial activity against Staphylococcus aureus and Shigella flexneri. Synergistic effect in inhibition was observed when Hedyotis diffusa extract was mixed Sophora subprostrata extract as compared to each extracts alone. Finally, the growth inhibition curves were determined by using ethyl acetate extracts of Hedyotis diffusa against Staphylococcus aureus and Salmonella Typhimurium. The methanol extract of Hedyotis diffusa had strong antimicrobial activity against Staphylococcus aureus at the concentration of 4,000 ppm. At this concentration, the growth of Staphylococcus aureus was retarded more than 36 hours and up to 24 hours for Salmonella Typhimurium. In conclusion, the methanol extracts of Hedyotis diffusa inhibit efficiently Staphylococcus aureus and Salmonella Typhimurium.