Wu Ding-Tao, Feng Kang-Lin, Li Fen, Hu Yi-Chen, Wang Sheng-Peng, Gan Ren-You, Zou Liang
Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, 610106, China.
Institute of Food Processing and Safety, College of Food Science, Sichuan Agricultural University, Ya'an, 625014, Sichuan, China.
Curr Res Food Sci. 2022 Apr 21;5:752-762. doi: 10.1016/j.crfs.2022.04.004. eCollection 2022.
Polysaccharides exist as one of the most abundant components in lotus leaves, which attract increasing attention owing to their promising health-promoting benefits. In this study, the digestive and microbial degradation characteristics of lotus leaf polysaccharides (LLP) were studied by using an gastrointestinal model. The results suggested that LLP was stable in the human upper gastrointestinal tract according to its digestive stabilities at different simulated digestion stages. Conversely, the indigestible LLP (LLPI) could be remarkably utilized by intestinal microbiota in human feces during fermentation, and its fermentability was 58.11% after the fermentation of 48 h. Indeed, the microbial degradation characteristics of LLPI during fermentation by human fecal inoculum were revealed. The results showed that the content of reducing sugars released from LLPI obviously increased from 0.498 to 2.176 mg/mL at the initial fermentation stage (0-6 h), and its molecular weight sharply decreased from 4.08 × 10 to 2.02 × 10 Da. Notably, the molar ratios of arabinose (Ara), galactose (Gal), and galacturonic acid (GalA) in LLPI decreased from 2.89 to 1.40, from 5.46 to 3.72, and from 21.24 to 18.71, respectively, suggesting that the utilization of arabinose and galactose in LLPI by intestinal microbiota was much faster than that of galacturonic acid at the initial fermentation stage. Additionally, LLPI could remarkably regulate gut microbial composition by increasing the abundances of several beneficial microbes, including and , resulting in the promoted generation of several short-chain fatty acids, especially acetic, propionic, and butyric acids. The findings from the present study are beneficial to better understanding the digestive and microbial degradation characteristics of LLP, which indicate that LLP can be used as a potential prebiotic for the improvement of intestinal health.
多糖是荷叶中含量最丰富的成分之一，因其具有促进健康的潜在益处而受到越来越多的关注。在本研究中，利用胃肠模型研究了荷叶多糖（LLP）的消化和微生物降解特性。结果表明，根据LLP在不同模拟消化阶段的消化稳定性，其在人体上消化道中是稳定的。相反，难消化的LLP（LLPI）在发酵过程中可被人粪便中的肠道微生物群显著利用，发酵48小时后其发酵率为58.11%。事实上，揭示了人粪便接种物发酵过程中LLPI的微生物降解特性。结果表明，在发酵初期（0-6小时），LLPI释放的还原糖含量从0.498明显增加到2.176mg/mL，其分子量从4.08×10急剧下降到2.02×10Da。值得注意的是，LLPI中阿拉伯糖（Ara）、半乳糖（Gal）和半乳糖醛酸（GalA）的摩尔比分别从2.89降至1.40、从5.46降至3.72和从21.24降至18.71，这表明在发酵初期，肠道微生物群对LLPI中阿拉伯糖和半乳糖的利用速度远快于半乳糖醛酸。此外，LLPI可通过增加包括和在内的几种有益微生物的丰度来显著调节肠道微生物组成，从而促进几种短链脂肪酸的产生，尤其是乙酸、丙酸和丁酸。本研究结果有助于更好地理解LLP的消化和微生物降解特性，这表明LLP可作为改善肠道健康的潜在益生元。
