Quality Evaluation, Antioxidant Capacity Assessment, and Environmental Correlations of Sinopodophyllum hexandrum From...

Sinopodophyllum hexandrum, a Berberidaceae medicinal herb, contains lignans and flavonoids with anticancer, antibacterial, antiviral, and expectorant activities, and its antioxidant capacity underpins therapeutic effects. This study evaluated the quality and antioxidant capacity of S. hexandrum from 12 Qinghai Plateau origins, and analyzed their correlations with environmental factors. Cluster analysis classified the origins into three groups. Principal component analysis (PCA) showed that the first four principal components contributed a cumulative variance of 86.395%, with podophyllotoxin-4-O-glucoside (PPG) as the main contributor. Orthogonal partial least squares-discriminant analysis (OPLS-DA) further confirmed PPG as a key origin discriminant (VIP > 1). Comprehensive quality evaluation recognized P3 (Huzhu), P2 (Ledu), and P11 (Nangqian 2) as high-quality origins. While antioxidant capacity analysis showed strong activity in P10 (Nangqian 1) samples-with 4'-demethylepipodophyllotoxin (4'-DMEP) as the key related component. Redundancy analysis (RDA) and Mantel Test results showed that component contents (especially quercetin, PPG, and podophyllotoxin [PPT]) and antioxidant capacity of S. hexandrum correlated significantly with environmental factors. Notably, antioxidant capacity correlated significantly with B1 (precipitation supply capacity and temperature fluctuation stability), and quercetin was the most environment sensitive component. This study provides a scientific basis for resource protection, elite germplasm screening, and targeted cultivation of S. hexandrum.