• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.1
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• pp.65-71
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• 2000

Chitosan oligosaccharide, chitosan polysaccharide and monolaurin were used to impart the antimicrobial properties onto paper for food products . Staphylococcus aureus (ATCC 25923) was used as test microorganism and shake flask test was carried out in order to examine the antimicrobial activity of each sample. Chitosan oligosaccaride showed the greatest antimicrobial effect among them and gave the promising result even at the concentration of 0.005%. Its antimicrobial power was enhanced when it is used with nomolaurin together. Chitosan oligosaccharide improved the tensile strength of antimicrobial paper.

• Food Science and Preservation
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• v.2 no.1
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• pp.203-207
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• 1995

Spices(Tumeric, Celery-seed, Cumin, Black pepper, Coriander) were irradiated at dose levels of 0, 5, 7 and 9kGy using Co60 source and stored at room temperature. After 12 months of storage following 9kGy irradiated spice, total aerobic bacteria were significantly decreased. When the irradiation dose was 7kGy, microbial levels showed l02-103 levels. However, total lactic acid bacteria and E-coli were shown negative at below 5kGy.

• The Korean Journal of Community Living Science
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• v.21 no.1
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• pp.13-18
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• 2010

This study was performed to investigate the antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens. The growth inhibitory effects of the extract at a concentration of 250, 500, 1,000 or 2,000 mg/L on food poisoning microorganism were determined against Salmonella typhimurium, Listeria monocytogenes, Yersinia enterocolitica, Escherichia coli O157:H7 and Staphylococcus aureus. The microorganisms growth was not affected by the extract at the concentration up to 250 mg/L, but was significantly (p<0.05) inhibited by the extract at a concentration higher than 1,000 mg/L. The extract of Euphorbia humifusa had strong antimicrobial activity against all test strains at a concentration of 2,000 mg/L. The results in the present study demonstrate antimicrobial effects of Euphorbia humifusa ethanol-extract against food-borne pathogens, suggesting that Euphorbia humifusa could be an effective natural antibacterial agent in food.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.260-263
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• 2006

In this study, we investigated the antimicrobial effect of 14 different herbal petal extracts on various foodborne and food spoilage bacteria. Herbal petal extracts were prepared with 70% ethanol followed by sequential hexane, chloroform, ethyl acetate, n-butanol, and water fractionation. Antimicrobial activity was highest in the ethanol fraction from roselle (Hibiscus sabdariffa L.) petals as determined by the paper disc method. The roselle ethanol extract retarded the growth of food spoilage bacteria in kimbap (rice rolled in dried laver). Foodborne microorganisms (e.g. Bacillus cereus and Clostridium perfringens), on the other hand, were most efficiently inhibited by the ethyl acetate fraction of the roselle petal extract as determined by growth inhibition curves. Our study shows that roselle petals harbor antimicrobial activity against foodborne and food spoilage microorganisms. The critical ingredient is highly enriched in the ethyl acetate fraction of the extract.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.277-280
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• 2006

This study was carried out to investigate the effect of HPLT on the inactivation rates of microorganisms in raw milk depending on the pressurization time and temperature. Raw milk samples were submitted to HPLT of 200 MPa at -4, 4, 12 and $20^{\circ}C$, respectively. Inactivation increased with pressurization time and HPLT of microorganisms at 200 MPa was time dependent at any temperature. At sub-zero temperature of $-4^{\circ}C$, high pressure pasteurization was the most effective in inactivating microorganisms.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1327-1332
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• 1998

The optimum thermal condition of retort Biji product was determined by heat penetration curve, aerobic bacteria count and sensory test. Retort Biji showed a simple logarithmic heating curve regardless of solid content. Heating time was a $26{\sim}27$ min until Fo value reached 9 min and the amount of microorganism in the Biji product sterilized for 26 min at $121^{\circ}C$ were decreased to $10^{-4}\;CFU/g$, indicating the safe range for retort product. The rate of heat penetration was reduced as solid content and size of product were increased, whereas sterilization temperature and initial temperature of product influenced the heat penetration curve. Sensory scare indicated that there was no significant difference in color, flavor, and appearance among different thermal processes. However, Biji product sterilized at $121^{\circ}C$ showed the highest score in overall preference value.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.9
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• pp.1445-1450
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• 2004

The plum (Prunus salicina L., cv. ‘Soldam’) fruits were harvested at different growth stages, and then extracted using 80% methanol, respectively. The methanol extracts of plum were investigated for their growth inhibition on 6 kinds of human cancer cells using MTT assay and for their activity to induce quinone reductase (QR) in murine Hepa1c1c7 cells. Among various methanol extracts of plum, the plum 1~4 (immature fruit), which thin out 10~25 days before final harvest, showed higher anticarcinogenic activity against 5 kinds of cancer cells than plum 5~9 (intermediate-mature and mature fruit). Especially, plum 1 and 2 were exhibited the strongest growth inhibiting activities to AGS, HepG2 and MDA cancer cells. Also the plum extracts induced the activity of QR, an anticarcinogenic marker enzyme, in Hepa1c1c7 cells while the induction of QR activities by adding plum extracts were shown to be a little difference depending on growth stages. These results suggested that methanol extracts of immature plum can be considered as an effective natural cancer chemoprevention materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1479-1484
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• 2008

This study was conducted to investigate the quality characteristics of fermented-defatted soybean grits (DSG). Fermented-DSG was prepared by inoculating Bacillus subtilis NUCI into steamed DSG at 2% (v/w) concentration and fermenting at $40^{\circ}C$ for 24 hr. The protein contents of DSG and fermented-DSG were higher by $57.2{\sim}61.0%$ than those of Chungkukjang, but lipid contents of these samples were not detected. The protease and $\alpha$-amylase activities, and solid contents in DSG were not shown. However, the activities of protease and $\alpha$-amylase, tyrosine contents, fluid consistency, and viscous substance contents of fermented-DSG were higher than those of Chungkukjang. The levels of free amino acids and isoflavone of fermented-DSG tended to increase more than those of DSG. The sensory score of fermented-DSG were higher in odor and taste than those of Chungkukjang groups, while lower in color and overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.521-526
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• 2007

The effects of red ginseng powder on hepatotoxicity in $benzo(\alpha)pyrene\;[B(\alpha)P]$-treated mice were investigated. Male ICR mice were pretreated with red ginseng powder (50 or 100 mg/kg/day, for 5 days, intraperitoneally) before treatment with $B(\alpha)P$ (0.5 mg/kg, i.p, single dose). The ability of red ginseng powder to protect against oxidative damage to the mouse liver was examined by determining the level of lipid peroxide, glutathione, and the antioxidant enzyme activities. The glutathione content depleted by $B(\alpha)P$ were significantly increased by red ginseng powder, but elevation of lipid peroxide content induced by $B(\alpha)P$ was decreased by red ginseng powder. The increased activities of superoxide dismutase, catalase and glutathione peroxidase after $B(\alpha)P$-treatment were decreased by the treatment of red ginseng Powder; however, glutathione S-transferase activity depleted by $B(\alpha)P$ were significantly increased. These results suggest that red ginseng powder can protect against $B(\alpha)P$ intoxification through its antioxidant properties.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.363-370
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• 2017

In this study, we stored frozen shrimp (Litopenaeus vannamei) at $4^{\circ}C$ during 12 days and investigated the effect of chitosan coating with natural preservatives (0.05% carvacrol, 0.05% thymol) on the growth of microorganism (mesophilic bacteria, psychrophilic bacteria, Pseudomonas spp., $H_2S$ producing bacteria) and physiological characteristics (total volatile basic nitrogen and pH) and sensory evaluation (appearance, odor and general acceptance). Chitosan coating with natural antimicrobial compounds (0.05% carvacrol and 0.05% thymol) had inhibited the growth of all the target microorganism and showed the significant antimicrobial activity (p < 0.05) to mesophilic bacteria, psychrophilic bacteria and $H_2S$ producing bacteria until 12 day (the last day of this study). These treated groups had showed the significant difference (p < 0.05) in total volatile basic nitrogen and all the sensory characteristics but not in pH. Therefore, chitosan coating combined with natural antimicrobial compounds (0.05% carvacrol and 0.05% thymol) showed the effective antimicrobial activity on major spoilage microorganism on shrimp and could be used to elongate the shelf life of refrigerated shrimp.