木质素基多酚的制备及生物活性

Preparation and Bioactivities of Lignin-based Polyphenols

针对木质素活性位点低,活性差的问题,利用酸性熔盐水合物通过一锅法脱甲基化及酚化改性制备了木质素基多酚化合物即连苯三酚改性木质素(PEHL)。实验结果表明:脱甲基化木质素(DEHL)和PEHL的反应位点显著增加,含酚羟基的量由原料酶解木质素(EHL)中的1.25 mmol/g分别提高到3.49和5.70 mmol/g。DPPH·清除实验发现,木质素基多酚化合物的抗氧化活性显著增加,与EHL对DPPH·抑制率(25.4%)相比,质量浓度10 mg/L下DEHL和PEHL的DPPH·清除率分别提高了46.9和64.4个百分点;PEHL展示了良好的抑菌活性,添加量1 g/L时对大肠杆菌和金色葡萄球菌的抑制率分别为85.22%和99.76%;木质素基多酚还表现出较低的细胞毒性。

Aiming at the problems of low active sites and poor activity of lignin,pyrogallol modified enzymatic hydrolyzed lignin(PEHL),a lignin-based polyphenol compound,was prepared by one-pot demethylation and phenolic modification from acidic molten salt hydrate.The experimental results demonstrated a significant increase in the reaction sites of demethylated enzymatic hydrolyzed lignin(DEHL)and PEHL,with phenolic hydroxyl groups increasing from 1.25 mmol/g in raw enzymatic hydrolyzed lignin(EHL)to 3.49 and 5.70 mmol/g,respectively.Furthermore,DPPH·scavenging experiments revealed a significant enhancement in the antioxidant activities of lignin-based polyphenol compounds,and the DPPH·scavenging rates of DEHL and PEHL increased by 46.9%and 64.4%,respectively.Moreover,PEHL showed promising antibacterial activity,and low cytotoxicity with inhibition rates of E.coli and S.aureus by 85.22%and 99.76%,respectively.