Comparative Study on Anti-Inflammatory Effect of Polysaccharides from Vinegar-Baked Radix Bupleuri Using Different Methods

[Image: see text] The impact of the extraction method on the physiochemical characteristics and anti-inflammatory effect of polysaccharides from vinegar-baked Radix Bupleuri (VBCPs) was studied. Five extraction methods were employed to obtain the VBCPs: hot water extraction (HW), ultrasound-assisted extraction (UA), enzyme-assisted extraction (EA), citric acid-assisted extraction (CA), and ammonia-assisted extraction (KA). The results showed that the extraction method affects the yield, characteristics, and anti-inflammatory effect of the polysaccharides significantly. KA produced the highest yield, Ara content, and the strongest effect of enhancing IL-10 secretion. VBCP-EA exhibited the largest molecular weight (Mw), the highest Man content, and the poorest effect on inhibiting NO, VBCP-UA possessed more Gal than other VBCPs, the lowest Mw, and a comparable effect on inhibiting NO and TNF-α with VBCP-KA and VBCP-CA. All VBCP self-assembled into nanoparticles in solutions, and VBCP-KA presented the lowest particle size. The structure–activity analysis showed that Mw and Man content are negatively correlated and Ara content is positively correlated with the NO inhibition and IL-10 secretion effects; Rha and Gal A content are positively correlated and Glu is negatively correlated with the TNF-α inhibiting effect. The above results indicated that KA is an efficient method for obtaining anti-inflammatory VBCP, which provides new insight into the extraction of VBCP.