We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships be...We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships between the structure and emulsifying, thickening, moisture-absorption, and moisture-retention capabilities of rhodococcal FACEPS using S-2 EPS produced by R. rhodochrous strain S-2. We prepared chemically deacylated S-2 EPS (DeAcyl S-2 EPS) and palmitoylated DeAcyl S-2 EPS (ReAcyl S-2 EPS), and compared them with native S-2 EPS. All of the properties were attenuated and recovered by deacylation and reacylation of S-2 EPS, respectively. These results suggest that the fatty acid moiety of rhodococcal FACEPS is involved in such functional properties. We also showed that palmitoylation improved the emulsifying, moisture-ab-sorption, and moisture-retention abilities of other acidic polysaccharides that are commercially available. These results suggest that the acidity of the polysaccharide backbone is at least partly responsible for the observed functionality of fatty acid-containing polysaccharides. To our knowledge, this is the first report on multifunctional property of an anionic polymer incorporating low amounts of hydrophobic residues. The present findings could be useful for the creation of new multifunctional surfactants from renewable raw materials for use in various industries, e.g., in cosmetics.展开更多
The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the...The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40-48 h and when the pH value was 4 under 30℃.Glucose was the most suitable carbon source for LAB-producing EPS.The rough EPS was obtained from L15 culture after centrifugation,dialysis,deprotein,decoloration,and ethanol-precipitation.The sample was at least composed of two polysaccharides that were completely different in molecular weight and the amount.The purified EPS was passed through the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.展开更多
A new extracellular polysaccharide (EPS-I) isolated and purified from Z_ 222 ,a strain of Lactic acid bacteria has been investigated. Sugar composition analysis,methylation analysis and 1H NMR and 13 C NM...A new extracellular polysaccharide (EPS-I) isolated and purified from Z_ 222 ,a strain of Lactic acid bacteria has been investigated. Sugar composition analysis,methylation analysis and 1H NMR and 13 C NMR spectroscopy reveal that the EPS-I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two-dimensional NMR spectroscopy,including heteronuclear multiple-bond correlation (HMBC) and nuclear overhauser effect spectroscopy (NOESY).展开更多
从生水牛乳中筛选出两株高产胞外多糖(EPS)的乳酸菌株LB2、LB7,经MRS肉汤培养基发酵后,菌液中的胞外多糖(EPS)产量分别达135 mg/L、148 mg/L,通过形态学、生理生化特征、API细菌鉴定系统、16S r RNA序列分析,鉴定出菌株LB2为植物乳杆菌(...从生水牛乳中筛选出两株高产胞外多糖(EPS)的乳酸菌株LB2、LB7,经MRS肉汤培养基发酵后,菌液中的胞外多糖(EPS)产量分别达135 mg/L、148 mg/L,通过形态学、生理生化特征、API细菌鉴定系统、16S r RNA序列分析,鉴定出菌株LB2为植物乳杆菌(Lactobacillus plantarum),LB7为类肠膜魏斯氏菌(Weissella paramesenteroides)。将其应用到水牛乳酸奶的发酵中,结果表明,植物乳杆菌LB2和类肠膜魏斯氏菌LB7均可用来发酵水牛乳酸奶,且能有效增加酸奶的黏度和胞外多糖产量,其黏度和EPS产量分别为4 050 m Pa·s和149 mg/L。展开更多
文摘We have been studying the function and structure of fatty acid-containing extracellular polysaccharides (FACEPS) produced by bacteria belonging to the genus Rhodococcus. In this study, we examined the relationships between the structure and emulsifying, thickening, moisture-absorption, and moisture-retention capabilities of rhodococcal FACEPS using S-2 EPS produced by R. rhodochrous strain S-2. We prepared chemically deacylated S-2 EPS (DeAcyl S-2 EPS) and palmitoylated DeAcyl S-2 EPS (ReAcyl S-2 EPS), and compared them with native S-2 EPS. All of the properties were attenuated and recovered by deacylation and reacylation of S-2 EPS, respectively. These results suggest that the fatty acid moiety of rhodococcal FACEPS is involved in such functional properties. We also showed that palmitoylation improved the emulsifying, moisture-ab-sorption, and moisture-retention abilities of other acidic polysaccharides that are commercially available. These results suggest that the acidity of the polysaccharide backbone is at least partly responsible for the observed functionality of fatty acid-containing polysaccharides. To our knowledge, this is the first report on multifunctional property of an anionic polymer incorporating low amounts of hydrophobic residues. The present findings could be useful for the creation of new multifunctional surfactants from renewable raw materials for use in various industries, e.g., in cosmetics.
文摘The influencing factors of extracellular polysac-charide(EPS)produced from a strain of lactic acid bacteria(LAB L15)were studied by using the phenol-H2SO4 method.It was demonstrated that the strain produced EPS at the most amount when it was incubated for 40-48 h and when the pH value was 4 under 30℃.Glucose was the most suitable carbon source for LAB-producing EPS.The rough EPS was obtained from L15 culture after centrifugation,dialysis,deprotein,decoloration,and ethanol-precipitation.The sample was at least composed of two polysaccharides that were completely different in molecular weight and the amount.The purified EPS was passed through the SephadexG-200 column and it showed that it was a sample purified by thin layer chromatography.
文摘A new extracellular polysaccharide (EPS-I) isolated and purified from Z_ 222 ,a strain of Lactic acid bacteria has been investigated. Sugar composition analysis,methylation analysis and 1H NMR and 13 C NMR spectroscopy reveal that the EPS-I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two-dimensional NMR spectroscopy,including heteronuclear multiple-bond correlation (HMBC) and nuclear overhauser effect spectroscopy (NOESY).
