• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.6
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• pp.1080-1086
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• 1996

Monascus strains were isolated from Ang-Khak for the screening of antimicrobial activity. Two Monascus isolates, No.116 and No.481, were selected because they showed strong antimicrobial activity. Effect of various nutrients and incubation conditions on antimicrobial activity were different between two isolates. Strong antimicrobial activity of isolate No.116 was observed in the medium with 8% sucrose and $0.8%(NH_4)_2SO_4,$ 0.5% $KH_2PO_4and$ 0.5% $MgSO_4,$ while isolate No.481 required 8% sucrose, 1.6~2% $(NH_4)_2SO_4,$ 0.5% $MgSO_4and$ 0.5% $FeSO_4for$ the highest activity. The strong antimicroial activity was observed when both isolates were incubated on rice extract broth with initial pH of 5.3. The optiimum incubation temperature for the highest antimicrobial activity was $32.5^{\circ}C.$ With optimal conditions for the highest antimicrobial activity, isolate No.116 and No. 481 were both active for 51 hours or longer against test organisms Bacillus subtilis, Staphylococcus aureus, Listeria monocytogenes, and Enterococcus faecium.

• Food Science and Preservation
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• v.13 no.2
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• pp.246-251
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• 2006

Organic compost is a useful fertilizer for organic farming. However, it poses a microbiological hazard to the farm produce because most of the compose are originated from excrementitious matters of domestic animals. Irradiation was performed to improve microbiological safety of organic compost and the effectiveness of gamma-irradiation for inactivating Salmonella typhimurium and E. coli was investigated. Total aerobic bacteria and coliform bacteria in 16 produce or commercial compose were ranged from $10^5\;to\;10^7\;CFU/mL\;and\;0\;to\;10^3\;CFU/mL$, respectively. All coliform bacteria in the composts were eliminated by irradiation at 5 kGy, while about $10^2\;CFU/mL$ of total aerobic bacteria survived up to 10 kGy of irradiation. In the inoculation test the test organisms (inoculated at $10^7\;CFU/mL$) were eliminated by irradiation at 3 kGy. $D_{10}$ values of inoculated Salmonella typhimurium and E. coli in the compost were $0.4{\pm}0.05\;and\;0.39{\pm}0.03kGy$. It was considered that $3{\sim}5kGy$ of gamma irradiation was effective for radicidation (radiation sterilization of pathogenic microbes) of organic fertilizer.

• 한국해양학회지
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• v.19 no.2
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• pp.153-162
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• 1984

This study was conducted to interpret the relations between the polychaete community and its environments in Kwangyang Bay during July, 1982. The type of sediments in the study area varies from sand to clay and the organic content obtained by ignition was in the ranges of 0.3% to 15.4%. The polychaetes which occurred at 25 stations comprised 70 species representing 63 genera and had an average density of 490 animals/m$\^$2/. The most abundant species were Lagis bocki (20%), Lumbrineris longifolia (10%), Chohe teres (7%), and Sternaspis scutata (5%). The polychaete populations show the highest density in muddy sand sediments and have a tendency to decrease their abundance in finer sediments such as bud and clay. The individual numbers of each feeding type show the same tendency. Kwangyang Bay consists of three distinct characteristic communities, representing different physical and biological factors: delta community, muddy flat community and channel community. Delta community has very poor organisms and seems to be determined by physical factors such as tidal current, and by sediment conditions and seems to be determined by physical factors such as tidal current, and by sediment conditions and by the food availability. Muddy flat community shows more diverse and higher abundance than delta community but seems to be impoverished by the stress of oxygen deficiency in sediments. Channel community has the highest density in the study area and comprises more various feeding types. This is probably due to the supply of allochthonous materials from the Seomjin River and offshore as food, the heterogeneous sediments and some biological interactions within habitats.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.355-359
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• 1998

Platelet activation is originated by the intracellular or/and extracellular $Ca^{2+}$. Agonist-induced $Ca^{2+}$ entry through a plasma-membrane pathway has been reported repeatedly, but the mechanisms has proven harder to elucidate. Recently, a number of natural products have been isolated from medicinal plants and marine organisms and have proved to be useful chemical tools for resolving the mechanism of cellular functions. In an attempt to understand the mechanism of platelet activation in Bupleuri Radix, we have studied some aspects of the isolation of active components and their dependence of external $Ca^{2+}$> on platelet activation. Acetone extract of Bupleuri Radix has the most activity on platelet activation and it's active components were identified as saikosaponin a and d. Their optimal concentration was respectively $20\;\mu\textrm{g}/ml$ and $5\;\mu\textrm{g}/ml$ and their platelet activation was not dependent on external $Ca^{2+}$>, whereas optimal concentration of each agonist was arachidonic acid ($10\;\mu\textrm{M}$), collagen ($10\;\mu\textrm{M}/ml$), thrombin (0.1 unit/mi), PAF (5 nM), PMA ($5\;\mu\textrm{M}$), ionophore A23187 ($2\;\mu\textrm{g}$) and their dependence of external $Ca^{2+}$> on platelet activation appeared to thrombin > collagen $\geq$ PAF > PMA > arachdonic acid> ionophore A23187. These results suggest that saikosaponin is different from each agonists in the dependence of external $Ca^{2+}$ on platelet activation.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.587-592
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• 1991

The curd yogurt was prepared from milk or milk added with skim milk powder or four types of rice powder. Acid production by lactic acid bacteria in milk containing additive of 2% (w/v) was investigated and quality of curd yogurt (sensory property and keeping quality) was examined. Some organic acids in curd yogurt were analyzed by HPLC. Four types of rice powder, particularly brown rice, stimulated acid production by lactic acid bacteria more than control (milk yogurt). Among four organisms tested, Leuconostoc mesenteroides and Lactobacillus bulgaricus produced more acid than L. casei and L. delbrueckii. HPLC analysis of organic acids in curd yogurt showed that the amount of lactic acid markedly increased during the fermentation by L. bulgaricus for 24 hours while the amount of citric acid markedly decreased. Addition of rice powders to milk slightly reduced sensory property of curd yogurt. Among four types of rice powder tested, tongil rice added sample showed better sensory acceptability than other samples. When curd yogurt was kept at $5^{\circ}C$ for two weeks, acidity and number of viable cells of curd yogurt were not changed.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.1-7
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• 1991

The object of this study was to investigate the enzyme system in kimchi during fermentation. The results were as follows; 1. Pectinesterase (PE) activity initially increased, following a decrease in kimchi juice but progressively decreased in kimchi solid. 2. Polygalacturonase(PG) activity in kimchi juice initially increased following a decrease near to absence and then increased again. PG activity in kimchi solid, initially decreased following a increase. 3. Peroxidase (POD) activity in kimchi juice initially increased, following a decrease and that in kimchi solid progressively decreased. 4. The activity of ascorbic acid oxidase(AAO) in kimchi juice slightly decreased, following a increase but decreased again. The activity of AAO in kimchi solid, progressively decreased. The cause for the slight increase of the activities of enzymes in kimchi juice after kimchi making was thought to be the extracting effects from kimchi solid. The disappearance of all enzyme activities in fermentation was due to the decrease of pH and the inactivation of enzymes owing to prolongation of fermentation. The cause of increase of PG activity in late fermentation, may be the proliferation of aerobic organisms.

• Food Science of Animal Resources
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• v.28 no.1
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• pp.76-81
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• 2008

The objective of this study is to evaluate the microbial safety of raw pork used to produce Korean pork jerky. The raw pork samples harbored large populations of microorganisms. In particular, mesophilic bacteria were found to be most numerous $(3.9{\times}10^2-3.9{\times}10^5cfu/g)$ in the samples. Spore-forming bacteria and coliforms were not detected below detection limit. Yeast and molds were detected at $3.8{\times}10^1-5.1{\times}10^2cfu/g$ in the raw pork. Ten samples of raw pork were analyzed for the presence of pathogenic bacteria. Bacillus cereus was isolated from samples B and J and Staphylococcus aureus was isolated from sample B. The B. cereus isolates from raw pork samples were identified with 99.8% agreement and S. aureus isolate was identified with 97.8% agreement according to the API CHB 50 kit.

• Journal of Food Hygiene and Safety
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• v.6 no.3
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• pp.119-126
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• 1991

ABSTRACT - This study was performed to investigate the possible effect of Lactobacillus spp. on the growth and citrinin production by Penicillium citrinum. Lactobacillus bulgaricus and Lactobacillus casei were grown with Pen. citrinum in modified APT broth containing 7% of glucose and incubated at $30^{\circ}C$ for 15 days. Four inoculation procedures were used; (a) Lactobacillus spp. and Pen. citrinum were grown alone(Pc, Lb, and Lc), (b) both organisms were added simultaneously(ST; Pc+Lb and Pc+Lc), (c) Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc), and (d) Pen. citrinum was grown 3 days, then Lactbacillus spp. was added (PcLb and PcLc). At 0, 3, 6, 9, 12, 15 days of incubation, the growth of each organism, pH and total acidity of broth, and content of citrinin were determined. Lactobacillus spp. and Pen. citrinum, when grown associatively, influenced the growth of each other. It was observed that slower growth of Pen. citrinum when in the presence of Lactobacillus spp. than when the mold grew alone. Production of citrinin by Pen. citrinum was markedly less in the mixed culture. No apparent growth and toxin production was observed when the Lactobacillus spp. was grown 3 days, then conidia of Pen. citrinum were added(LbPc and LcPc). The above results indicate that another microorganism or competing microflora in the culture can affect the behavior of Pen. citrinum.trinum.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.700-706
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• 1990

The curd yogurt was prepared from milk or milk added with skim milk powder or soy proteins. Acid production by lactic acid bacteria in milk containing additive of 2% was investigated and quality of curd yogurt(sensory property and keeping quality) was examined. Some organic acids in curd yogurt were analyzed by HPLC. The soy proteins, particularly defatted soy flour or soy flour, stimulated acid production by lactic acid bacteria more than skim milk powder. Among the four organisms tested, Leuconostoc mesenteroides and Lactobacillus bulgaricus produced more acid than L. casei and L. delbrueckii. HPLC analysis of organic acids in curd yogurt showed that the amount of lactic acid and acetic acid markedly increased during the fermentation by L. bulgaricus for 24 hours while the amount of citric acid markedly decreased. The major organic acid produced during the fermentation was lactic acid. Addition of soy proteins to milk reduced sensory property of curd yogurt. Among the soy proteins tested, soy protein concentrate or soy protein isolate added sample showed better sensory acceptability than other samples. When curd yogurt was kept at $5^{\circ}C$ for two weeks, titratable acidity, pH and number of viable cells of curd yogurt were not changed.

• Food Science and Preservation
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• v.20 no.5
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• pp.684-690
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• 2013

The antioxidant and photoprotective effects of various extracts from the roots of Rumex crispus L. were evaluated. The concentrations ($IC_{50}$) of various extracts required to exert a 50% reducing effect on a DPPH radical were found to be 0.005~0.093 mg/mL. The ethyl acetate extract showed a more remarkable effect than the positive control ascorbic acid. The concentrations ($QC_{50}$) of the butanol and ethyl acetate extracts required to exert a 50% reducing effect on the singlet oxygen $^1O_2$ were found to be 0.464 and 0.365 mg/mL, respectively. Both extracts were also found to protect the in vitro biological system from the detrimental effect of a singlet oxygen $^1O_2$ on type II photosensitization in E. coli and genomic DNA. Among all the tested extracts, the ethyl acetate and butanol extracts contained higher amounts of total phenolic contents. The results suggest that our study may contribute to the development of new bioactive products with potential applications to the reduction of photo-produced oxidative stress involving reactive oxygen species in living organisms.