Le Bao, Pham Thi Ngoc Anh, Yang Seung Hwan
Faculty of Pharmacy, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
Department of Biotechnology, Chonnam National University, Yeosu 59626, Korea.
Foods. 2020 Dec 6;9(12):1808. doi: 10.3390/foods9121808.
In the present study, we assessed the extraction of low molecular weight soluble polysaccharides (MESP) from soybean by-products using microwave-assisted enzymatic technology and proposed the chemical structure of MESP using Fourier transform-infrared spectroscopy, gas chromatography, and H and C nuclear magnetic resonance spectrum analysis. The results suggested that MESP mainly comprised arabinose, rhamnose, and glucuronic acid with (1→4) glycosidic linkages in the backbone. Compared with inulin, MESP was found to selectively stimulate the growth of probiotics. Moreover, the results of in vitro fermentation indicated that MESP significantly increased the concentrations of both acetate and butyrate ( < 0.05). MESP were treated on lipopolysaccharide (LPS)-stimulated RAW264.7 cells to determine the anti-inflammatory effect in vitro. It was observed that MESP inhibited nitric oxide, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10 production. Furthermore, Western blotting results indicated that MESP significantly attenuated LPS-induced downregulation of phosphorylation levels of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3) in macrophages. The underlying mechanism might involve inhibition of the expression of pro-inflammatory cytokines, presumably via JAK2/STAT3 pathway. Collectively, the results of our study paved way for the production of MESP, which may be potentially used as nutraceutical ingredients for prebiotics and anti-inflammatory agents, from soybean residue.
在本研究中，我们评估了利用微波辅助酶技术从大豆副产品中提取低分子量可溶性多糖（MESP）的方法，并通过傅里叶变换红外光谱、气相色谱以及氢和碳核磁共振光谱分析对MESP的化学结构进行了推测。结果表明，MESP主要由阿拉伯糖、鼠李糖和葡萄糖醛酸组成，主链中含有（1→4）糖苷键。与菊粉相比，发现MESP能选择性地刺激益生菌生长。此外，体外发酵结果表明，MESP显著提高了乙酸盐和丁酸盐的浓度（P<0.05）。用MESP处理脂多糖（LPS）刺激的RAW264.7细胞以测定其体外抗炎作用。观察到MESP抑制了一氧化氮、肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β、IL-6和IL-10的产生。此外，蛋白质印迹结果表明，MESP显著减轻了LPS诱导的巨噬细胞中Janus激酶2（JAK2）和信号转导子及转录激活子3（STAT3）磷酸化水平的下调。潜在机制可能涉及抑制促炎细胞因子的表达，推测是通过JAK2/STAT3途径。总体而言，我们的研究结果为从大豆残渣中生产MESP铺平了道路，MESP可能潜在地用作益生元的营养成分和抗炎剂。
