[Biological synthesis of L-ascorbyl palmitate].
Biological synthesis of L-Ascorbyl Palmitate in organic system were studied in this text. The contradiction between conversion of vitamin C and concentration of L-Ascorbyl Palmitate were resolved. High conversion of vitamin C and concentration of L-Ascorbyl Palmitate were obtained by Novo435. A series of solvents(log P from -0.24 to 3.5 )were investigated for the reaction,and acetone was found to be the most suitable from the standpoint of the enzyme activity and solubility of L-ascorbic. And the equilibrium of the reaction was affected by the addition of the molecular sieves and temperature. Reaction carried out at 60 degrees C and with 20% 0.4nm molecular sieves is good for the enzyme to keep its activity and for making the equilibrium go to the product. With 1.094 g palmitic acid, 0.107 g vitamin C and 0.020 g Novo435, rotate rate of 200 r/min, the conversion of ascorbic reached 80% and the concentration of L-ascorbyl palmitate is 20 g/L after 48 h. Furthermore, reaction batch of Novo435 and substrates recycle were observed, the result indicated that Novo435 may used 4-5 times continuously with high conversion. And 6-O-unsaturated acyl L-ascorbates were synthesized through Novo435 condensation of ascorbic acid and various unsaturated fatty acids with high conversion in this text.
Xu
Feng-Jie
FJ
College of Life Science and Technology, Beijing University of Chemical and Technology, Beijing 100029, China.
Tan
Tian-Wei
TW
D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D002384:Catalysis; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism*; D008049:Lipase / Q000737:chemistry / Q000378:metabolism*
D004800:Enzymes, Immobilized; D008049:Lipase; D001205:Ascorbic Acid; C031226:6-O-palmitoylascorbic acid