Hong-Xia Zhao's research while affiliated with Jiangsu University and other places

Publications (2)

Article
Full-text available
D-isoascorbic acid is a food antioxidant additive and used in accordance with Good Manufacturing Practice (GMP). High solubility in water (about 150 g/L at 25[degree sign]C) reduces its effectiveness in stabilizing fats and oils. Our research group had successfully synthesized D-isoascorbyl palmitate using immobilized lipase Novozym 435 as a biocat...
Article
Full-text available
Isoascorbic acid is a stereoisomer of L-ascorbic acid, and widely used as a food antioxidant. However, its highly hydrophilic behavior prevents its application in cosmetics or fats and oils-based foods. To overcome this problem, D-isoascorbyl palmitate was synthesized in the present study for improving the isoascorbic acid's oil solubility with an...

Citations

... Interestingly, the kinetic parameters under UI were significantly altered compared with those under mechanical shaking. A previous study has shown that the V max and k m values of esterification of D-isoascorbyl palmitate under ultrasound was pronouncedly elevated by 2.85 and 1.50 times, respectively, compared with those under mechanical shaking [22]. The Bi-bi ping-pong model is extensively used in estimating parameters of lipase-catalyzed reaction kinetics since it was built for the reaction with two or more substrates and products [20]. ...
... However, when the enzyme is in excess, a problem arises in the diffusion of the substrate [25,26], leading to a reduction in the conversion of octyl formate. This occurs due to the limited internal and external mass transfer associated with high enzyme loading [4,7,26,27]. The non-contributing behavior of excessive immobilized enzyme towards higher molar conversion, and associated reduced product yield, was also reported in the production of amyl isobutyrate [28] and citronellyl acetate [15]. ...