The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic...The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic, space group C2 with a = 19.391(3), b = 5.715(4), c = 15.755(3) ? b = 115.23(1), V = 1579(1) 3, Z = 4, Dc = 1.335 g/cm3, F(000) = 672, m = 0.099 mm-1, R = 0.033 and wR = 0.060 for 1278 observed reflections (I > 2s(I)). The complex consists of (R)-mandelic acid and (R)-phenylalanine in 1:1 molar ratio, and the complex molecules form layered crystal structure by self-assembly through intermolecular H-bonding between carboxyl and carboxylate of the neighboring molecules.展开更多
A novel phenanthrene (PHE)-degrading strain named as Sphingomonas sp.GF2B was isolated and identified from a farmland soil.Effects of a synthetic surfactant (Tween-80) and a rhamnolipid biosurfactant on PHE degradatio...A novel phenanthrene (PHE)-degrading strain named as Sphingomonas sp.GF2B was isolated and identified from a farmland soil.Effects of a synthetic surfactant (Tween-80) and a rhamnolipid biosurfactant on PHE degradation by Sphin- gomonas sp.GF2B were investigated at different concentrations of the surfactants.The results showed that Sphingomonas sp.GF2B was able to mineralize up to 83.6% of PHE within 10 days without addition of surfactants.The addition of Tween-80 to the reaction medium inhibited greatly PHE biodegradation,with only 33.5% of PHE degraded.However,the biosurfactant facilitated PHE biodegradation,with up to 99.5% of PHE degraded.The preferential utilization of PHE as a carbon source and the enhanced solubility of PHE by the biosurfactant were likely responsible for the higher biodegra- dation efficiency of PHE in the presence of the biosurfactant.Therefore,it could be concluded that the application of the biosurfactant to PHE-contaminated soils was perhaps a feasible way to facilitate the PHE biodegradation.展开更多
基金The work was supported by the National Natural Science Foundation of China (29973036)
文摘The racemic phenylalanine has been separated by (R)-mandelic acid through the formation of diastereomeric molecular complex. The crystal of the title chiral complex (C8H8O3 C9H11NO2, Mr = 317.33) belongs to monoclinic, space group C2 with a = 19.391(3), b = 5.715(4), c = 15.755(3) ? b = 115.23(1), V = 1579(1) 3, Z = 4, Dc = 1.335 g/cm3, F(000) = 672, m = 0.099 mm-1, R = 0.033 and wR = 0.060 for 1278 observed reflections (I > 2s(I)). The complex consists of (R)-mandelic acid and (R)-phenylalanine in 1:1 molar ratio, and the complex molecules form layered crystal structure by self-assembly through intermolecular H-bonding between carboxyl and carboxylate of the neighboring molecules.
基金Supported by the National Natural Science Foundation of China (No. 20377024)the National High Technology Research and Development Program (863 Program) of China (Nos. 2007AA061101 and 2009AA063103)
文摘A novel phenanthrene (PHE)-degrading strain named as Sphingomonas sp.GF2B was isolated and identified from a farmland soil.Effects of a synthetic surfactant (Tween-80) and a rhamnolipid biosurfactant on PHE degradation by Sphin- gomonas sp.GF2B were investigated at different concentrations of the surfactants.The results showed that Sphingomonas sp.GF2B was able to mineralize up to 83.6% of PHE within 10 days without addition of surfactants.The addition of Tween-80 to the reaction medium inhibited greatly PHE biodegradation,with only 33.5% of PHE degraded.However,the biosurfactant facilitated PHE biodegradation,with up to 99.5% of PHE degraded.The preferential utilization of PHE as a carbon source and the enhanced solubility of PHE by the biosurfactant were likely responsible for the higher biodegra- dation efficiency of PHE in the presence of the biosurfactant.Therefore,it could be concluded that the application of the biosurfactant to PHE-contaminated soils was perhaps a feasible way to facilitate the PHE biodegradation.
