Studies On The Extracts Of Larix Gmelinii Bark And Their Antioxidant Synergistic Effects

This study is based on the efficient use of the important forestry by-product Larix gmelinii bark.Supercaritical CO2 extraction and ultrasonic assisted ethanol extract were used for extraction in sequence. The components of two extracts weredetected,respectively. Then the study of alcohol extract on antioxidant activity and synergistic effect analysis were investigated.The supercritical CO2 extract wasexamined by GC-MSand 44 components were detected, the major constituents of the extractswere5,6-2-ol-β-Carotene(36.30%), resin acids and their derivatives (27.60%), manool (17.14%), geranyl linalool (12.51%), all of these constituentsare of high economic value.The alcohol extract was rich in proanthocyanidins, flavonoids, polyphenols. and was examined by HPLC-ESIMS. Results proved that there were 3 proanthocyanidinsmonomer,4B-type dimers and 1 trimers. What’s more, flavonoid including taxifolin and larixinol, organic acids including ferulic acid and coffee acid,lignans including secoisolariciresinol etc. were found. The extracts was fractionated by ethyl acetate by which can separate polymers and oligomers.Antioxidant capacity assay was investigated under DPPH and TBARS system, DPPH free radical scavenging ability of each single samplewas in turn:VC>PE>LOPC>RT>LPPC>CE, on the other hand, anti lipid peroxidation ability was as follows:LOPC>PE>RT>LPPC>CE.The direct comparison method, addition method and the Isobologram analysis method were used to judge synergistic effect between every two antioxidants.In DPPH system,VC, rutin combined with PEand LOPC showed bettersynergistic effect. The corresponding rutin combined with LOPC showed a better synergistic effect in the TBARS system.