Aims: In this study, some physical properties of Bacillus sp. exo-polysaccharide were investigated. Methods and Results: An extracellular polysaccharide was purified by sequential precipitations after homogenization of the diluted culture supernatant of Bacillus sp. CP912. Its physical properties were examined such as lipid emulsifying effect on several vegetable oils and flocculating activity against the activated carbon suspension. The melting point and endothermic calories of the polysaccharide were 128AE7°C and 50AE864 kCal mol )1 , respectively. Its pyrolysis temperature was 284AE58°C. The polysaccharide showed high lipid emulsifying activity on oil-water emulsion, against olive, peanut, sunflower and corn oils. It exhibited high flocculating activity as well against activated carbon. Conclusions: The present findings suggest that the extracellular polysaccharide produced by Bacillus sp. CP912 has a great industrial potential because of its high lipid emulsifying and flocculating activity. Significance and Impact of the study: These data represent a novel Bacillus sp. extracellular polysaccharide possessing high emulsifying and flocculating effects.

An improved extraction method for ethyl carbamate, a genotoxic and carcinogenic compound found in various fermented foods and beverages, was investigated for its determination in the two most typical Korean traditional rice wines, takju and yakju. When the rice wines were extracted twice with chloroform at 30 degrees C for 60 min, the recovery of ethyl carbamate was less than 16%. When they were saturated with NaCl before extraction, the recovery of ethyl carbamate increased to 24.4% in takju and 67.2% in yakju. Adjustment of pH to 9.0 after NaCl saturation in takju resulted in a dramatic increase of recovery to 81.2%, but not in yakju. When the contents of ethyl carbamate and its precursor, urea, in various Korean traditional rice wines were determined, there was no correlation between the two contents. This is due to the fact that storage time is more important than urea content in the formation of ethyl carbamate in rice wine. In addition, its storage at high temperature resulted in a dramatic increase in ethyl carbamate content according to the prolonged storage time, suggesting that storage time and temperature play a key role in the formation of ethyl carbamate in Korean traditional rice wine.

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