School of Pharmaceutical Sciences, Health Science University of Hokkaido, Kanazawa, Tobetsu, Hokkaido 061-0293, Japan.
Department of Forensic Medicine, Graduate School of Medicine, Hokkaido University, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
Steroids. 2020 Jun;158:108605. doi: 10.1016/j.steroids.2020.108605. Epub 2020 Feb 19.
Steryl glucosides (SGs) and acylated steryl glucosides (ASGs) are phytochemicals found in plant-based foods and are known as bioactive compounds with potential health benefits. These include anti-inflammatory properties, anti-diabetic effects, and modulation of immunoregulatory functions as well as having cholesterol lowering effects. In this study, three major SGs, i.e., glucosides of β-sitosterol, stigmasterol, and campesterol, were synthesized and used as standards for measurement of their contents in rice bran (RB)-based fermented food (FBRA) utilizing Aspergillus oryzae and raw material (RM). The compounds were quantified using liquid chromatography/electrospray ionization-tandem mass spectrometry. It was found that β-sitosteryl glucoside was most abundant among the analyzed glucosides in both samples, and the contents of each SG in FBRA decreased about 35% from those of RM. In contrast to SGs, the contents of ASGs in FBRA increased 1.5-fold during the fermentation process as evidenced by an alkaline hydrolysis. The present results suggest that the FBRA might have greater beneficial effects than the RM, since ASGs have shown to have more potent cholesterol lowering effects and stronger anti-diabetic properties than SGs.
甾醇葡萄糖苷（SGs）和酰化甾醇葡萄糖苷（ASGs）是植物性食物中含有的植物化学物质，被认为是具有潜在健康益处的生物活性化合物。它们具有抗炎、抗糖尿病和调节免疫调节功能的特性，同时还具有降低胆固醇的作用。在这项研究中，我们合成了三种主要的 SG，即 β-谷甾醇、豆甾醇和菜油甾醇的葡萄糖苷，并利用米糠（RB）为原料，利用米曲霉（Aspergillus oryzae）发酵生产发酵食品（FBRA），将其作为测量标准。使用液相色谱/电喷雾串联质谱法对这些化合物进行了定量分析。结果发现，在所分析的糖苷中，β-谷甾醇葡萄糖苷在两种样品中含量最多，而 FBRA 中每种 SG 的含量比 RM 中的含量降低了约 35%。与 SGs 不同，FBRA 中的 ASGs 含量在发酵过程中增加了 1.5 倍，这可以通过碱性水解得到证明。本研究结果表明，FBRA 可能比 RM 具有更大的有益作用，因为 ASGs 具有比 SGs 更强的降低胆固醇作用和更强的抗糖尿病特性。
