Optimization of Microwave-Assisted Extraction of Pectin from Premna Microphylla by Response Surface Method and Its Antioxidant Activity

Pectin is abundant in Premna microphylla and has uarious biological activities.Its microwave-assisted extraction process was optimized by Box-Behnken design on the basis of a series of single-factor experiments. Meanwhile, the antioxidant activity of pectin was assessed by scavenging assays of hydroxyl and superoxide anion free radicals.The results indicated that, the optimal extraction conditions are microwave power 635 W,extraction time 29 s and liquid-material ratio 20 : 1(m L/g). Under the optimal conditions,the maximum extraction rate is 20.49%. Extracted pectin had strong scavenging capacity on hydroxyl and superoxide anion free radicals in a dosage-dependent manner and the pectin from Premna Microphylla has strong antioxidant capacity.