Structural Analysis And Antioxidant Activities Of Polysaccharide Isolated From Pleurotus Ferulae Lenzi

In this paper, the Pleurotus ferulae Lenzi was used as the main material. The PFLPs(Pleurotus ferulae Lenzi polysaccharides) was studied systematically, included the extraction, purification and separation of different component. 1. Isolation and purification of polysaccharidesThe hot water extraction method with ultrasonic assistant method was used to extract PFLPs. By the purification of the DEAE-52 ion-exchange chromatography and the gel filtration chromatography on Sephadex G-150, two main pure fractions were got, coded as PFLP1 and PFLP2 2. Structural Analysis of of PFLP1 and PFLP2The structure was analyzed by gel filtration chromatography, gas chromatography(GC), partial acid hydrolysis, periodate oxidation, Smith degradation, methylation, Fourier transform infrared spectrum(FT-IR), 1H-Nuclear magnetic resonance(1H-NMR), Congo red experiment and iodine-potassium experiment. The result indicated that the relative molecular mass analysis showed that PFLP1 was 9900 Da and composed of L-Rha, D-Gal, D-Glu and D-Man with a molar ration of 1︰3.64︰18.6︰1.54. PFLP2 was 10300 Da; monosaccharide composition of L-Rha, D-Glu, D-Gla, D-Xyl and D-Man with a molar ration of 1︰6.76︰4.28︰1.08︰0.65. The main glycosidic bond configuration of PFLP1 and PFLP2 were 1â†'2, 1â†'3, 1â†'4 and 1â†'6; Both of them were proteoglycan with β-D-glycopyranoside; They were triple helical structure. The side chains was long and branche relatively more. 3. The antioxidant activities of PFLP1 and PFLP2The antioxidant activity tests in vitro indicated that PFLP1 showed high DPPH(64.52%, 5 mg/mL) and ABTS(94.26%, 5 mg/mL) scavenging activities. The hydroxyl radical scavenging activity was not so good. The reducing power activity, Fe2+ chelating activity, and superoxide radical scavenging activity were low. PFLP2 showed high hydroxyl radical(64.78%, 5 mg/mL), DPPH(81.85%, 5 mg/mL) and ABTS(85.97%, 5 mg/mL) scavenging activities, moderate superoxide radical scavenging activity, lower reducing power activity, and Fe2+ chelating activity. The results suggested that PFLP1 and PFLP2 could be used as potential natural antioxidants.