증기폭쇄 방법으로 국내산 대나무줄기에서 추출된 리그닌의 자외선 차단효과

Abstract

Bamboo trees have high economic values because of rapid growth rate, rich biomass components and good health effects. Among several parts of bamboo tree, bamboo stem contains a considerable amount of cellulose and lignin, and a little amount of minerals, silica, and etc. In this study, domestic bamboos (Phyllostachys bambusoides (1) and Phyllostachys nigra var. henosis (2)) lignins were prepared by steam explosion (temperature 210oC, 2 MPa) and organosolv pretreatment. The results showed that steam explosion lignin (SEL1, SEL2) had a higher yield (12% and 21%). Characteristics of lignin structures were confirmed by FT-IR, and SUP1/SUPH-, SUP13/SUPC-, and 2D HSQC NMR. SEL1 and SEL2 were the typical GHS-type lignins and their bonds units were predominantly β-O-4’linkages. Antioxidant effects were assayed by DPPH and ABTS radical scavenging activity using ascorbic acid as a standard. The antioxidant activity of SEL1 was the best, and IC50 value of 383.89±25.35 μg/mL and 131.78±0.99 μg/mL, respectively. Cytotoxic concentration levels of all lignin samples were 100 μg/mL based on MTT assay. To confirm the UV protection effect of lignin, SEL1 was added to commercial sunscreen (SPF 15) and moisturizing cream (no SPF) respectively. Addition of 10 wt% lignin to commercial sunscreen increased 45% of UV absorbance higher than moisturizing cream after 2 h of UV (UVA+UVB) radiation. The result of lignin addition has shown synergistic effects in UV protection and antioxidant effect.