超声辅助低共熔溶剂提取的鳞杯伞多糖的体外消化与酵解特性

In vitro digestion and fermentation characteristics of Clitocybe squamulosa polysaccharides extracted by ultrasound-assisted deep eutectic solvents

本研究主要探讨体外消化与粪便发酵对超声辅助低共熔溶剂提取的鳞杯伞多糖(D-CSFP)的化学组成、结构特征和生物活性的影响。结果表明,经唾液-胃-肠消化后,D-CSFP的还原糖含量分别从0.44mg/mL上升到0.45、0.55和0.57mg/mL;分子量分别由35312Da降低到32090、25519和25473Da,但D-CSFP的官能团结构无明显改变。体外粪便发酵后,D-CSFP发酵液的OD600数值呈先增高后下降的趋势,为0.63→1.24→1.19;pH由6.75降低至6.13(P<0.05);总碳水化合物含量由8.59 mg/mL降低至5.05 mg/mL(P<0.05);总短链脂肪酸含量由1.83 mmol/L显著上升至11.15mmol/L(P<0.05)。16SrRNA测序结果显示:D-CSFP可有效促进有益菌(如Bacteroides、Prevotella和Dialister)的相对丰度,抑制有害菌(如Klebsiella)的繁殖。综上所述,D-CSFP可作为一种潜在功能性食品被充分开发利用。

This study aims at investigating the effects of in vitro digestion and fecal fermentation on the chemical composition,structural characteristics and biological activities of Clitocybe squamulosa polysaccharides(D-CSFP)extracted by ultrasound-assisted deep eutectic solvents.The results showed that after saliva,stomach and intestine digestion,the content of D-CSFP increased from 0.44 mg/mL to 0.45,0.55 and 0.57 mg/mL respectively and the molecular weight of D-CSFP decreased from 35312 Da to 32090,25519 and 25473 Da respectively,but the structure of D-CSFP had no obvious change.After fecal fermentation in vitro,the OD600 of D-CSFP fermentation broth increased first and then decreased(0.63→1.24→1.19);pH decreased from 6.75 to 6.13(P<0.05);the total carbohydrate content in D-CSFP fermentation broth decreased from 8.59 mg/mL to 5.05 mg/mL(P<0.05);the total short chain fatty acids(SCFA)content was significantly increased from 1.83 mmol/L to 11.15 mmol/L(P<0.05).16S rRNA sequencing results showed that D-CSFP could effectively promote the relative abundance of beneficial bacteria(such as Bacteroides,Prevotella and Dialister),and inhibit the propagation of harmful bacteria(such as Klebsiella).In conclusion,D-CSFP can be used as a potential functional food to promote intestinal health.