Khizar Hayat

Separation and Purification of Flavonoid from Ginkgo Extract by Polyamide Resin

An efficient separation process of flavonoid from Ginkgo extract was developed in this study. Polyamide resin offered the fine adsorption capacity, and its adsorption rate at 25°C fitted well to the Langmuir isotherm. Dynamic adsorption and desorption experiments were conducted to optimize the separation process of total flavonoids from the Ginkgo extract. After one run, the content of total flavonoids increased from 24.0% to 55.0%. The method will provide a potential approach for large-scale separation and purification of flavonoid for its wide pharmaceutical use.

Efficient lipase-selective synthesis of dilauryl mannoses by simultaneous reaction–extraction system

An efficient method for enzymatic-selective synthesis of dilauryl mannoses was developed using lipase-catalyzed condensation of d-mannose and lauric acid in a simultaneous reaction–extraction system. The highest equilibrium conversion of diesters of 51% (1,6-diester: 14%; 3,6-diester: 18%; 4,6-diester: 19%) and the total conversion of mono and dilauryl mannoses of 76% were achieved at the n-hexane/acetonitrile ratio of 1:1, the molar ratio of lauric acid to mannose of 4:1, 60xa0g/l molecular sieves and 5xa0g/l lipase at 50°C for 72xa0h in 15xa0ml SRE system. The new system will be important for the synthesis of dilauryl mannoses.