Optimization of the lotus leaf flavonoids preservative agent using response surface analysis

Flavonoids, which exhibt excellent biological activity and good pharmacological values, are the main active components in the lotus leaf. In order to obtain optimal protective agent of flavonoids in lotus leaves from leachate, the unoxidized rate of the flavonoids in lotus various solutions was investigated to assess the effect of different protective agents. Response surface method (RSM) was adopted relying on Box-Behnken test design principles, and the design-expert software was employed subsequently to establish a functional relationship between the influence factors and response values. Results suggested that the best performance in 100mL leachate was acquired when the dosage of glucuronide-α-Lactone was 0.280g with 0.444g niacinamide and 54.0μL hytic acid according to resultant regressive equation. Under this condition, the unoxidized rate of the flavonoids in lotus was 96.98%. The preliminary study set a primary basis to further the development and use of flavonoids in lotus leaves and relevant plants.