Evaluation of physicochemical and DPPH· Cleaning activity of ultrasonic assisted extraction of polysaccharide from leonurus japonicus

Abstract

Leonurus japonicus is rich in bioactive compounds especially polysaccharide. Single factors test and response surface methodology were used to study the optimum conditions for ultrasonic - assisted extraction of polysaccharide from L. japonicus, and its physiochemical and DPPH scavenging activities also were evaluated. The optimal conditions as underpinned by this paper is as follow: extraction temperature of 70 °C, extraction time of 50 min and extraction power of 210W. The polysaccharide of L. japonicus was shown to be a non-reducing sugar and to exhibit DPPH scavenging activity to an extent. The polysaccharide structures were studied using SEM, AFM, and FT-IR. It showed L. japonicus polysaccharide had been having more than one chains which were branched and entangled with each other. and existed a broad band wavelength of 2925.64, 1635.06, 1539.7, 1046.73, and 477.86 cm-1. The study indicated that L. japonicus may have a beneficial use to the medical and food industries.