• Maxillofacial Plastic and Reconstructive Surgery
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• v.27 no.6
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• pp.523-527
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• 2005

Allograft donations are commonly found to be contaminated. The most of tissue banks has promoted the use of ionizing radiation for the sterilization of biological tissues. The potential for transmission of human infectious diseases and contamination of microorganism has created serious concern for the continued clinical use of hard and soft-tissue allografts. Tissue banks have employed 15-25kGy for sterilization of hard and tendon allografts, which, according to the national standards, approaches the level at which the tissue quality is adversely affected for transplantation. The donations of allogeneic tissues to the Korea Tissue Bank over a 2-year period were reviewed, and the incidence and bacteriology of contamination were detailed. Clinical outcomes were determined for donors who had positive cultures at the time of retrieval and during the processing and they were compared with those of post sterilization. After exposure of the frozen block bone to 25kGy and the processed tissues to 15kGy of gamma irradiation, the authors were able to demonstrate complete inactivation of the bacteria. The aim of this study was to obtain the effects of gamma irradiation and the irradiation dose according to the type of tissue, through conventional microbiologic test without on influence of biocompatibility in allografts. The contamination rate after the final irradiation sterilization is 0% in the processed allografts. This may be due to the fact that the gamma radiation and processing steps are effective to control contamination.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.277-281
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• 2000

Agar, one of the most abundant marine products has not been utilized extensively because of low level of processing technology in Korea. This research was carried out to improve the utilization of agar and consequent increase in profit. Antibacterial activity of agarooligosaccharides were evaluated against bacteria causing putrefaction and flood poisoning. Addition of 0.4% agarooligosaccharides showed antibacterial activity toward Staphylococcus aureus and Escherichia coli O157:H7; furthermore, autoclave treatment of agarooligosaccharides solution enhanced the antibacterial activity. Agarooligosaccharides showed high stability against the pH change. Addition of amino acid(alanine, lysine, glycine, phenylalanine) in agarooligosaccharides solution enhanced antibacterial activity in E. coli O157:H7, Streptococcus mutans and Staphylococcus aureus.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.1-5
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• 1992

Antibacterial activity of the water-soluble portion of Ulmus pzcmila L. extract against 10 bacterial species was studied by both cylinder plate dilution method and broth dilution test tube method. Inhibitory effect of the extract on the bacteria was also investigated by plotting bacterial survival at various concentration of the extract. The crude extract exhibited antibacterial activity against all of the tested bacterial species with exception of K pneurnoniae. The fractions of the extract prepared by CM Sephadex-C 50 ion exchange chromatography were also subjected to test the antibacterial activity, and the activity was studied after autoclaving for 20 minutes.

• Korean journal of food and cookery science
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• v.13 no.3
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• pp.293-298
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• 1997

The changes of microorganisms, pH, color and flavor were examined in the chicken treated with O％, 1%, 2%, and 3% lactic acid solutions during the storage at 4$^{\circ}C$. Lactic acid treatment inhibited the growth of mesophiles, psychrotrophs, and enteric bacilli as the concentration increased, however, it was not effective on yeasts and molds. Extension of lag phase for mesophilic bacteria and suppression of log phase for psychrotrophs and enteric bacilli were observed in the growth inhibition patterns. The pH of the chicken increased during the storage and antimicrobial effect of lactic acid appears to be due to mainly the decrease of pH. No flavor change of the chicken was observed by any lactic acid treatment, however, 3％ lactic acid caused discoloration of the chicken.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.184-191
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• 2008

Entomopathogenic bacteria (Xenorhabdus nematophila, X. sp. and Photorhabdus temperata subsp. temperata) isolated from entomopathogenic nematodes express potent insecticidal activity in insect hemocoel. They are also known to suppress insect immune mediation by inhibiting phospholipase $A_2$, leading to host immunosuppression. This study analyzed effects of their cultured broths on inhibiting insect immunosuppression. For this, we removed all bacterial cells using $0.2\;{\mu}m$ pore sized membrane from the bacteria-cultured broth. All three sterilized cultured media, in dose-dependent manners, significantly inhibited hemocyte-spreading behavior of 5th instar larvae of Spodoptera exigua. However, they showed differential inhibitory activities among different bacterial species, in which X. nematophila showed the most potent inhibitory activity. This immunosuppressive effect was applied to increase the pathogenicity of Bacillus thuringiensis (Bt). All three bacterial cultured broths including bacterial cells significantly potentiated Bt pathogenicity against young S. exigua larvae when each of them was orally administered in a mixture of low dose of Bt. Finally, we tested the effect of oral administration of the cultured media containing the immunosuppressive compound(s) secreted by the bacteria. The membrane-sterilized cultured broths were mixed with the low dose of Bt and then orally administered to the young S. exigua. Only the cultured medium of X. nematophila showed increase of Bt pathogenicity. These results indicated that the; cultured media of the three bacteria possessed immunosuppressive factor(s), which may act to potentiate Bt toxicity to young S. exigua larvae.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.276-282
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• 1982

The UHT treatment and consequent storage effect on nutritional value of milk are discussed. Compared with the conventional sterilization the UHT treatment of milk represents a relatively small thermal stress. During UHT processing, nutritive value of protein, fat, carbohydrates, fat-soluble vitamins and minerals are generally unaffected. Nutritive value of some water soluble vitamins and protein are adversely affected in a small degree during storage. It has been recommended that UHT milk has best nutritional and organoleptic qualities on storage under refrigeration. Some unsolved future problems are also suggested.

• 한국약용작물학회:학술대회논문집
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• 2011.04a
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• pp.168-169
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• 2011

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.613-618
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• 1999

This study investigated the effect of tea fungus/kombucha(TF) beverage on body weights, pancreas weights, serum glucose and lipid concentrations of both normal and diabetic male rats. Sprague Dawley male rats weighing $140{\pm}10g$ were randomly assigned to one control and five streptozotocin(STZ) diabetic groups. Diabetic groups were divided into D control(TF free water), 20% TFD(20% TF in water), 40% TFD(40% TF in water), 20% TFSD(20% TF disinfection in water) and 40% TFSD(40% TF disinfection in water) according to the level of TF supplementation. Diabetes was experimentally induced by intraperitoneally administration of STZ in citrate buffer(pH4.3) after 3 week feeding of four experimental water. Animals were sacrificed at the 4 week of diabetic state. The diabetic groups showed significant decrease of body weight(-29.4~48.6g) compared with the control group(72.4g). Pancreatic weights relative to body weights in all diabetic groups were heavier than those of the control group. The levels of fasting serum glucose were higher in all diabetic groups than that of the control group. The concentrations of triglyceride in serum was lower in 20% TFD and 20% TFSD groups than in those D control group. The levels of total cholesterol, LDL cholesterol in serum and atherogenic index were significantly decreased in all(20 or 40%) TFD and TFSD groups than in those D control group, but those were similar to control group. The levels of HDL cholesterol in serum was similar to all groups, but HDL cholesterol/total cholesterol ratio were significantly increased in all(20 or 40%) TFD and TFSD groups than in those D control group. Liver triglyceride concentration of the all diabetic groups significantly decreased compared with the control group. Liver total cholesterol and phospholipid were not affected by TF and TFS feeding. The results indicated that tea fungus/kombucha beverage feeding improved the cholesterol, triglyceride and atherogenic index levels in diabetic rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1157-1163
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• 2011

This study was conducted to investigate the cause of microbiological contaminants in aseptic chocolate milk and evaluate the effect of a physicochemical treatment on the growth inhibition of isolated bacterial strains. The bacterium isolated from aseptic chocolate milk was identified as Bacillus lentus and was named B. lentus M1. In the heat and pH treatment, the growth of B. lentus was inhibited at 110$^{\circ}C$ for >15 min and at pH's <5 and >10. An electrolyzed water treatment against B. lentus M1, revealed 5 mm growth past the inhibition zone. The effect of ozone gas on B. lentus M1 growth was evaluated using viable cell counts. When the initial number of B. lentus M1 was $10^2$ and $10^3$ CFU, the bacteria were completely suppressed by ozone gas treatment for 10 and 30 min, respectively. In a microwave treatment, B. lentus M1 was sterilized following microwave treatment for 1 min. As the result of ${\gamma}$-irradiation against B. lentus M1, numbers decreased as the ${\gamma}$-irradiation dosage increased. These results show the growth inhibition effects against contaminants in aseptic chocolate milk using physicochemical treatments.

• Korean Journal of Clinical Laboratory Science
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• v.52 no.4
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• pp.372-380
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• 2020

In this study, the sterilization ability of S. aureus and P. aeruginosa was evaluated using a plasma generator with a flexible electrode structure. Both strains were prepared at a concentration of 1.5×106 CFU/mL and inoculated and spread evenly on two medium plates. The medium were kept at a distance of 3 cm and 9 cm from the plasma generator and were plasma discharged from 30 sec to 10 minutes. The growth of colonies on the media, were subsequently compared with the control group. The mean colonies of S. aureus formed at a 3 cm distance were 9.2×102 (log value 2.96) CFU/mL for the 5 min discharge period and 8.0×10 (1.90) CFU/mL for the 10 min discharge period. When the medium was exposed for 5 min and 10 min at a 9 cm distance, the mean colonies of S. aureus formed were 2.16×103 (3.33) and 2.4×102 (2.38) CFU/mL, respectively. The medium containing P. aeruginosa kept at a 3 cm distance and exposed to 3, 5, 10-minute discharge, did not form any colonies. When kept at a 9 cm distance for 3 minutes, 6.0×102 (2.78) CFU/mL mean colonies were formed but no colonies were formed at exposure periods of 5 and 10 minutes. This enhanced sterilization effect was confirmed in experiments of S. aureus and P. aeruginosa using TiO2.