• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.382-387
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• 2007

The approval of use of certain food-grade phosphates as food additives in a wide variety of meat products greatly stimulated research on the applications of phosphates in foods. Phytic acid is a natural plant inositol hexaphosphate constituting 1-5% of most cereals, nuts, legumes, oil seeds, pollen, and spores. In this study, we investigated antibacterial activity of sodium phytate (SPT) against Salmonella typhimurium in tryptic soy broth with different pHs and in chicken, pork and beef. In tryptic soy broth, SPT at the concentrations of 0.1, 0.5, and 1.0% effectively inhibited the growth of Salmonella typhymurium in a concentration-dependent manner. At pH 5.5-7.0 similar to meat pHs, 1% SPT almost completely inhibited the bacterial growth. The inhibitory effect of SPT was stronger at pH 7.0 than pH 5.5. In chicken, pork, and beef, SPT at the concentrations of 0.1, 0.5, and 1% significantly inhibited the growth of Salmonella typhimurium in a dose-dependant manner (p<0.01). The addition of 1% SPT in the meats significantly increased the meat pHs. These results indicate that SPT is very effective for inhibition of bacterial growth as a muscle food additive for increasing food safety and functions.

• Journal of Aquaculture
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• v.21 no.2
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• pp.82-88
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• 2008

A 12-week feeding trial was conducted to investigate the effects of dietary supplementation of probiotics as a feed additive for juvenile Korean rockfish Sebastes schlegeli. Four experimental diets supplemented with no probiotic(Control), Bacillus polyfermenticus(BP), Bacillus licheniformis(BL) or Bacillus polyfermenticus plus Saccharomyces cerevisiae(BP+SC) at $1.0{\times}10^7$ CFU/kg diet as a dry-mater(DM) basis were prepared by mixing with a basal diet. After 12 weeks of the feeding trial, fish fed BP+SC diet showed significantly higher weight gain(WG), feed efficiency(FE), specific growth rate(SGR) and protein efficiency ratio(PER) than those of fish fed control diet(P<0.05), however there were no significant differences in WG, FE, SGR and PER among fish fed the BP, BL and BP+SC diets. Fish fed BP and BP+SC diets showed significantly higher condition factor(CF) than that of fish fed control and BL diets. Fish fed BP, BL, BP+SC diets showed significantly higher hepatosomatic index(HSI) than that of fish fed control diet, however there was no significant difference in HSI among fish fed BP, BL and BP+SC diets. Fish fed BP+SC diet showed significantly lower serum glucose than that of fish fed control diet, however there was no significant difference in serum glucose among fish fed BP, BL and BP+SC diets. Fish fed BP+SC diet showed significantly higher respiratory burst activity(NBT assay) than that of the fish fed control and BL diets, however there was no significant difference in NBT assay between fish fed BP and BP+SC diets. Fish fed BP and BL diets showed significantly higher lysozyme activity than that of the fish fed control diet, however there was no significant difference in lysozyme activity among fish fed BP, BL and BP+SC diets. Fish fed BP and BP+SC diets showed significantly lower cumulative mortality than that of the fish fed control diet, however there was no significant difference in cumulative mortality among fish fed BP, BL and BP+SC diets after the challenge test. From these results, dietary B. polyfermenticus, B. licheniformis and B. polyfermenticus plus S. cerevisiae supplementation in juvenile Korean rockfish diet could enhance growth performances, non-speicific immunities and a higher resistance against the specific pathogen.

• Korean Journal of Microbiology
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• v.39 no.4
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• pp.267-271
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• 2003

Burkholderia sp. D5, a polyaromatic hydrocarbons(PAHs)-degrading bacterium, was isolated from oil-contaminated soil. The bacterium could utilize phenanthrene (Phe) as a sole carbon source but could not use pyrene (Pyr). However, the strain could degrade Pyr when a cosubstrate such as yeast extract (YE) was supplemented. The PAH degradation rate of the bacterium was enhanced by the addition of other organic materials such as YE, peptone and glucose. YE was a particularly effective additive in stimulating cell growth as well as PAH degradation. When 1 g-YE/L was supplemented into the basal salt medium (BSM) with 215 mg-Phe/L, the specific growth rate (0.28 h-1) and Phe-degrading rate (29.30 μmol/L/h) were enhanced approximately ten and two times more than those obtained in the BSM with 215 mg-Phe/L, respectively. Through kinetic analysis, the maximum specific growth rate (μmax) and PAH degrading rate (Vmax) for Phe were obtained as 0.34/h and 289 ${\mu}mol$/L/h, respectively. Also, μmax and Vmax for Pyr were 0.27 h-1 and 50 ${\mu}mol$/L/h, respectively. The degradation rates for each Phe (2.20 μmol/L/h) and Pyr (2.18 μmol/L/h) were lower in mixture substrates than in a single substrate (29.30 ${\mu}mol$/L/h and 9.58 ${\mu}mol$/L/h, respectively). Burkholderia sp. D5 can degrade Phe and Pyr contained in soil, and the PAH degradation rates in soil were 20.03 ${\mu}mol$/L/h for Phe and 1.09 ${\mu}mol$/L/h for Pyr.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.37-44
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• 2007

The approval of use of certain food-grade phosphates as food additives in a wide variety of meat products greatly stimulated research on the applications of phosphates in foods. Although phosphates have never been classified as antimicrobial agents, a number of investigators have reported that phosphates have antimicrobial activities. Phytic acid is a natural plant inositol hexaphosphate constituting 1-5% of most cereals, nuts, legumes, oil seeds, pollen, and spores. In this study, we investigated antibacterial activities of sodium phytate(SPT), sodium pyrophosphate (SPP), sodium tripolyphosphate (STPP) on Escherichia coli O157:H7 on tryptic soy broth and in beef, pork and chicken. In tryptic soy broth, SPT, SPP and STPP at the concentrations of 0.05, 0.1, and 0.5% effectively inhibited the growth of Escherichia coli O157:H7 in a concentration-dependent manner. The bactericidal activity of SPT was the stronger than that of SPP or STPP at the same concentrations. In addition, the antibacterial effects of SPT, SPP and STPP at the concentrations of 0.05, 0.1, 0.3, and 0.5% on Escherichia coli O157:H7 were also investigated in raw or cooked meats including beef, pork and chicken. SPT, SPP and STPP significantly inhibited the bacterial growth in a dose-dependant manner (p<0.05). The bactericidal effect of SPT was stronger than that of SPP or STPP. The addition of SPT, SPP and STPP in meats increased meat pHs. SPP and STPP also increased the levels of soluble orthophosphate in meats but STP did not. These results indicate that SPT is very effective for inhibition of bacterial growth and that can be used as a muscle food additive for increasing functions of meats.

• Food Science and Preservation
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• v.21 no.2
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• pp.187-192
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• 2014

This study was conducted to develop a salad dressing using jujube (Zizyphus jujuba Miller) puree and to evaluate the processing and quality characteristics of the salad dressing containing various amounts (0, 10, 20, 30, 40, and 50%) of jujube puree. Jujube puree was prepared by crushing peeled, deseeded and steamed fruit flesh. The dressing ingredients (jujube flesh puree, soy sauce, vinegar, oligosaccharide, olive oil, and water) were mixed, homogenized, and packaged in glass bottles. The quality characteristics (color property, total titratable acidity, soluble solids, viscosity, phenolic compound content, antioxidant activity, and sensory acceptability) of the dressing were analyzed. The lightness ($L^*$) and redness ($a^*$) of the dressing tended to increase as the amount of the jujube puree increased whereas the hue angle ($h^{\circ}$) decreased. The total titratable acidity, soluble solids, viscosity, phenolic compound content, and antioxidant activity of the dressing increased with the addition of more jujube puree. The sensory acceptability (color, smell, taste, texture, and overall acceptability) were significantly higher in the dressing added with 30% added jujube puree than in the other samples. The results show that jujube flesh puree (approximately 30%) can be utilized as an additive for preparing a dressing with simultaneously high antioxidant activity and acceptability.