2017-2020年大同糯性白高粱抗性淀粉介导肠道菌群调节绝经大鼠脂代谢数据集

雌马酚作为大豆苷元的代谢产物，对比大豆苷元具有更高的生物活性与雌激素受体相结合，在人体中可以降低心血管疾病、骨质疏松症、乳腺癌、非酒精性脂肪肝等疾病发病率，而相关研究结果表明，食物组成极大的影响了肠道中雌马酚的形成，在可以刺激发酵的非淀粉多糖较高环境下，肠道菌能够迅速而完整的把大豆苷元转化为雌马酚，因此通过改善日粮方式来提高雌马酚产量以减轻绝经后女性肥胖具有较大的发展前景。本实验研究目的在于通过高粱(Sorghum)抗性淀粉对绝经大鼠肠道菌群结构的调节作用，进而探究抗性淀粉与豆制品协同对绝经大鼠脂代谢的影响，并探讨其调节机制。实验将高粱进行自然发酵 8 天，以增加高粱直链淀粉含量及回生值指标，利用碱提法提取高粱淀粉，通过压热复合酶法制备抗性淀粉，通过凝胶色谱-示差-多角度激光光散射仪、傅里叶红外光谱、X-射线衍射仪及扫描电镜等研究发酵预处理前后高粱抗性淀粉的结构变化；通过体内动物试验即利用 SD（Sprague-Dawley）大鼠，建立福美司坦绝经模型，并日常灌胃抗性淀粉，以是否给予含豆粕饲料为影响因素，通过大鼠体重、肝脏重量及腹脂数，肠道菌群结构变化，血脂生化六项、肝脏脂类相关酶活性及所表达基因含量等多角度共同证明了雌马酚对绝经肥胖大鼠的改善作用。研究结果如下： (1) 通过对发酵高粱直链淀粉含量及老化性质的测定，发酵 8 d 时直链淀粉含量最高，回生值较大，适合生产发酵高粱抗性淀粉。 (2) 通过压热复合酶法制备得到的抗性淀粉分的重均分子量及数均分子量均低于原料原淀粉；且发酵处理对于高粱老化过程的晶型排序没有太大的影响；高粱原淀粉在压热复合酶法处理后结晶结构被完全破坏，形成了 A+V 型晶体结构，从而产生了抗酶解性能；通过发酵处理的高粱抗性淀粉结晶度要低于未发酵的高粱抗性淀粉，扫描电镜可知高粱抗性淀粉表面均呈现深浅不一的条纹状沟壑。(3) 在相同剂量组抗性淀粉干扰饮食的前提下，给予普通含有豆粕饲料使绝经大鼠产雌马酚 Lactobacillus 及 Clostridium Xl Va 菌属的丰富度增加，即雌马酚含量更高，使大鼠的体重、腹脂及肝脏重量减小；且经过不同的含量 RS 和有无豆粕饲料的干预，血液中 LPL、HL 及 GE 的活性增加，肝脏中脂代谢的相关基因及相关酶活性与模型组差异显著，肝脏中脂肪空泡减小。 综上所述，本实验将高粱进行自然发酵后利用压热复合酶法制备抗性淀粉，通过灌胃 绝经大鼠探讨在有无含豆粕的条件下对绝经大鼠脂代谢的影响，证明了抗性淀粉与大豆苷元协同作用效果明显优于单独灌胃同剂量抗性淀粉，并初步验证了雌马酚在肝脏中调节脂代谢的功能基因及其作用靶点。

Equol, a metabolite of daidzein, exhibits higher biological activity and stronger binding affinity to estrogen receptors compared to daidzein. In the human body, it can reduce the incidence of cardiovascular diseases, osteoporosis, breast cancer, non-alcoholic fatty liver disease and other disorders. Relevant studies have shown that dietary composition greatly affects the formation of equol in the intestinal tract. Under the environment with high levels of fermentable non-starch polysaccharides, intestinal microbiota can rapidly and completely convert daidzein into equol. Therefore, improving equol production by optimizing dietary regimens to alleviate obesity in postmenopausal women has great development prospects.

The purpose of this experiment is to regulate the intestinal microbiota structure of formestane-induced postmenopausal rats using sorghum (Sorghum) resistant starch, explore the synergistic effect of resistant starch and soybean products on lipid metabolism in postmenopausal rats, and investigate its regulatory mechanism. In this study, sorghum was naturally fermented for 8 days to increase its amylose content and retrogradation value. Sorghum starch was extracted via alkali extraction method, and resistant starch was prepared using autoclaving combined with enzymatic method. Structural changes of sorghum resistant starch before and after fermentation pretreatment were characterized by gel permeation chromatography-refractive index detector-multi-angle laser light scattering (GPC-RID-MALLS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). In the in vivo animal experiment, Sprague-Dawley (SD) rats were used to establish the formestane-induced postmenopausal rat model, and they were daily gavaged with resistant starch. The influencing factors included whether soybean meal-containing feed was provided. Multiple indicators were measured to verify the improving effect of equol on obese postmenopausal rats, including rat body weight, liver weight and abdominal fat mass, changes in intestinal microbiota structure, six serum lipid biochemical parameters, liver lipid-related enzyme activities and gene expression levels.

The research results are as follows:
(1) The determination of amylose content and retrogradation properties of fermented sorghum showed that the amylose content was the highest and the retrogradation value was relatively high when fermented for 8 days, which is suitable for the production of fermented sorghum resistant starch.
(2) The weight-average molecular weight and number-average molecular weight of the resistant starch prepared by autoclaving combined with enzymatic method were lower than those of the raw native starch. Fermentation treatment had little effect on the crystal form ordering during the aging process of sorghum. The crystalline structure of native sorghum starch was completely destroyed after autoclaving combined with enzymatic treatment, forming an A+V-type crystal structure, which endowed it with anti-enzymatic hydrolysis properties. The crystallinity of fermented sorghum resistant starch was lower than that of unfermented sorghum resistant starch. Scanning electron microscopy observations revealed that the surfaces of sorghum resistant starch showed striated grooves of varying depths.
(3) Under the premise of the same dose of resistant starch intervention diet, feeding the postmenopausal rats with ordinary soybean meal-containing feed increased the abundance of Lactobacillus and Clostridium Xl Va genera, which elevated the equol content, and reduced the body weight, abdominal fat mass and liver weight of the rats. After intervention with different doses of RS and soybean meal-containing or non-soybean meal-containing feed, the activities of LPL, HL and GE in the blood increased. The liver lipid metabolism-related genes and enzyme activities were significantly different from those in the model group, and the hepatic fat vacuoles were reduced.

In summary, this experiment prepared resistant starch from naturally fermented sorghum using autoclaving combined with enzymatic method. The effect of gavage administration in postmenopausal rats with or without soybean meal-containing feed on lipid metabolism was investigated. It was proved that the synergistic effect of resistant starch and daidzein was significantly better than that of gavage administration of the same dose of resistant starch alone. The functional genes and their targets of equol in regulating liver lipid metabolism were preliminarily verified.