A strategy by exogenous addition of quorum sensing molecule farnesol to improve the production, antioxidant activity and antitumor activity of extracellular polysaccharide (EPS) of Grifola frondosa by liquid fermentation was proposed in the study. The highest yield of EPS induced by farnesol was 1.25 g/L, which was 150% higher than that of the control. Four polysaccharides including EPS-C-0M, EPS-C-0.2M, EPS-F-0M and EPS-F-0.2M were extracted and purified under the conditions of control and farnesol respectively. The physicochemical properties, antioxidant activities and antitumor activities were studied. Their chemical composition differed in sugar, protein and uronic acid contents, and they were composed of six constituent monosaccharides with different ratios, with the average molecular weights of 1.12 × 10³, 1.89 × 10³, 1.41 × 10³ and 2.02 × 10³ kDa, respectively. They presented similar FT-IR spectra, but different surface morphology. Antioxidant experiments showed that they had strong scavenging activities on ABTS⁺, hydroxyl radical, O²⁻ and DPPH radical. Antitumor experiments showed that they had strong inhibitory effects on human cervical cancer (HeLa) cells and human liver cancer cells (HepG₂) cells. Among the four polysaccharides, EPS-F-0.2M showed the highest antioxidant and antitumor activities, indicating that farnesol could regulate the biological activity of EPS by affecting structure and properties. These results demonstrated that appropriate adjustment of culture conditions had potential application in the development of polysaccharides with high antioxidant and antitumor activity. It provided a new strategy to enhance the production and bioactivity of edible and medicinal fungal polysaccharides by using quorum sensing molecules.

该研究提出了一种通过外源添加群体感应分子法尼醇来提高灰树花细胞外多糖(EPS)的液体发酵产量、抗氧化活性和抗肿瘤活性的策略。法尼醇诱导的EPS最高产量为1.25 g/L，比对照高150%。分别在对照和法呢醇条件下提取纯化EPS-C-0M、EPS-C-0.2M、EPS-F-0M和EPS-F-0.2M四种多糖。对其理化性质、抗氧化活性和抗肿瘤活性进行了研究。它们的化学成分不同，糖、蛋白质和糖醛酸含量不同，由六种不同比例的单糖组成，平均分子量为1.12×10³ kDa、1.89 × 10 ³、1.41 × 10 ³和2.02 × 10 ³ kDa。它们呈现出相似的 FT-IR 光谱，但表面形态不同。抗氧化实验表明，它们对ABTS ⁺、羟基自由基、O ^2-和DPPH 自由基有很强的清除活性。抗肿瘤实验表明，它们对人宫颈癌（HeLa）细胞和人肝癌细胞（HepG ₂） 细胞。在四种多糖中，EPS-F-0.2M 显示出最高的抗氧化和抗肿瘤活性，表明法尼醇可以通过影响结构和性质来调节 EPS 的生物活性。这些结果表明，适当调整培养条件在开发具有高抗氧化和抗肿瘤活性的多糖中具有潜在的应用价值。它为利用群体感应分子提高食用和药用真菌多糖的产量和生物活性提供了一种新策略。