[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.
College of Life Science and Technology, Beijing University of Chemical and Technology, Beijing 100029, China.
Feng-Jie
FJ
Xu
Tian-Wei
TW
Tan
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