不同品种膳食纤维降血脂功能的比较

连续4周给小鼠喂食高脂饲料(胆固醇1％、胆酸0．3％、猪油6％）后，其血清TC、LDL－C以及动物硬化指数（AI）显著升高，但血清TC和HDL－C无明显变化。在高脂饲料中加入6％多功能大豆纤维（MSF）、燕麦纤维或果胶后，可显著降低小鼠的血清TC、LDL－C及动脉硬化指数，但对血清TC和HDL－C无明显影响。同剂量的纤维素或小麦纤维，对小鼠的各项血脂参数均无明显影响。水溶性、粘性纤维可显著降低膳食胆固醇的吸收率和胆汗酸的重吸了率，从而起到明显的降血脂效果。水溶性纤维这方面的作用并不明显。     

不同品种膳食纤维降血脂功能的比较_注

连续 4周给小鼠喂食高脂饲料 (胆固醇 1%、胆酸 0 .3%、猪油 6 %)后 ,其血清TC、LDL -C以及动脉硬化指数 (AI)显著升高 ,但血清TC和HDL -C无明显变化。在高脂饲料中加入 6 %多功能大豆纤维 (MSF)、燕麦纤维或果胶后 ,可显著降低小鼠的血清TC、LDL -C及动脉硬化指数 ,但对血清TC和HDL -C无明显影响。同剂量的纤维素或小麦纤维 ,对小鼠的各项血脂参数均无明显影响。水溶性、粘性纤维可显著降低膳食胆固醇的吸收率和胆汁酸的重吸收率 ,从而起到明显的降血脂效果。水溶性纤维这方面的作用并不明显。     

膳食纤维的功能及开发研究

近一个时期来，膳食纤维引起世界各国营养学家的极大关注，将其列为“第七营养素”。早在1991年WHO专家组将膳食纤维推荐入“人群膳食营养目标”。膳食纤维是指不被人体消化吸收的以多糖类为主体的高分子物质的总称，按其溶解特性分为水溶性纤维和不水溶性纤维两大类：水溶性纤维是指植物细胞壁内的贮存物质和分泌物，主要包括果胶、树胶、葡聚糖、瓜儿豆胶、羧甲基纤维素等；不水溶性纤维是细胞壁的组成成分，包括纤维素、半纤维素、木质素     

膳食纤维的功能及开发研究

近一个时期来,膳食纤维引起世界各国营养学家的极大关注,将其列为“第七营养素”。早在1991年WHO专家组将膳食纤维推荐入“人群膳食营养目标”。膳食纤维是指不被人体消化吸收的以多糖类为主体的高分子物质的总称,按其溶解特性分为水溶性纤维和不水溶性纤维两大类:水溶性纤维是指植物细胞壁内的贮存物质和分泌物,主要包括果胶、树胶、葡聚糖、瓜儿豆胶、羧甲基纤维素等;不水溶性纤维是细胞壁的组成成分,包括纤维素、半纤维素、木质素和壳聚糖等。     

蒸汽爆破处理苦荞麸皮膳食纤维改性分析

目的：为了提高苦荞麸皮膳食纤维的综合利用率,采用蒸汽爆破技术对苦荞麸皮进行预处理,探究不同蒸汽爆破压力及保压时间对苦荞麸皮膳食纤维改性的影响。方法：以可溶性膳食纤维含量为主要指标得到最优蒸汽爆破改性条件,并对改性前后苦荞麸皮可溶性和不溶性膳食纤维的单糖组成、可溶性膳食纤维的理化性质及结构特性进行分析。结果：蒸汽爆破处理后,苦荞麸皮不溶性膳食纤维、纤维素、半纤维素、木质素及果胶含量显著降低（P＜0.05）,可溶性膳食纤维、可溶性糖、还原糖含量及总糖含量显著提高（P＜0.05）;最佳蒸汽爆破改性条件为1.2 MPa、90 s,在该条件下可溶性膳食纤维含量（12.36 g/100 g）较未蒸汽爆破处理（8.02 g/100 g）提高了54.11%;经最佳条件蒸汽爆破处理后,苦荞麸皮膳食纤维单糖组成发生改变,可溶性膳食纤维的持水力、持油力、膨胀力、α-淀粉酶活性抑制能力、葡萄糖吸收能力及热稳定性增强;可溶性膳食纤维羟基基团暴露增加,并呈现疏松多层蜂窝式网状结构。结论：蒸汽爆破预处理有助于提高苦荞麸皮可溶性膳食纤维含量,改善其理化结构特性,可为苦荞麸皮可溶性膳食纤维的利用及保健食品开发提供理论参考。     

膳食纤维对大鼠钙平衡及骨生物力学性能的影响

目的：研究不同结构的膳食纤维对钙平衡及生物力学性能的影响。方法：以大鼠作为动物模型分组饲养,分别饲喂含有50 g/kg麦麸、纤维素、木聚糖、果胶、菊粉、魔芋胶及其混合物的饲料。利用原子吸收光谱法检测饲料、粪便、尿样、股骨中钙含量;利用电解质分析仪测定血清中的总钙、游离钙、结合钙浓度;用三点弯曲法检测股骨的最大载荷。比较摄入不同膳食纤维大鼠钙吸收、血钙水平、尿钙流失、钙保留率、骨钙含量、骨的生物力学性能等参数的差异。结果：在钙吸收率方面,麦麸、纤维素组高于木聚糖、果胶、菊粉、魔芋组,其中木聚糖和魔芋组与麦麸组具有极显著差异（P<0.01）;在尿钙日排出量方面,木聚糖和纤维素组低于其余各组;在钙保留率方面,果胶组最低,处于负钙平衡;在血清钙水平方面,麦麸组血清游离钙浓度和其余实验组没有显著性差异（P>0.05）,但麦麸组结合钙和总钙浓度均高于其他各组;在骨钙含量和骨生物力学性能方面,果胶组明显低于其他各组,木聚糖组的骨最大载荷高于其他各组。结论：麦麸和纤维素等低发酵型膳食纤维的肠道钙吸收率高于木聚糖、果胶、菊粉、魔芋等高发酵型膳食纤维;木聚糖有助于提高大鼠骨生物力学性能;不同膳...     

膳食纤维对人体健康的影响

膳食纤维是包含纤维素、半纤维素、木质素、果胶及可溶性多糖等多种成分的混合物，膳食纤维具有多种生理保健功能，与人体健康密切相关，缺乏膳食纤维会引发多种疾病，所以含有膳食纤维的制品倍受消费者的青昧。     

甘薯膳食纤维构成及对乙醇发酵的影响

对14个甘薯品种(系)的膳食纤维构成成分进行了测定,分析了不同品种甘薯膳食纤维含量和组成差异及其对乙醇发酵的影响。结果表明:甘薯总膳食纤维(TDF)、不溶性膳食纤维(IDF)、可溶性膳食纤维(SDF)含量平均值分别为16.05、11.89、4.16 g/100 g干物质,变异系数分别为15.08%、13.79%、23.31%;甘薯果胶、半纤维素、纤维素和木质素含量平均值分别为33.35、37.46、21.10、2.13 g/100 g DF,变异系数分别为7.44%、16.68%、21.52%、16.89%,不同品种甘薯膳食纤维含量和组成差异显著。相关性分析表明,甘薯膳食纤维含量、各组成成分之间均显著正相关;发酵黏度与SDF、SDF/IDF、果胶显著正相关,而乙醇产量、发酵效率与膳食纤维相关性均不显著,因此甘薯果胶等SDF是影响乙醇发酵特性的重要因素。提高甘薯TDF和SDF含量可以作为高膳食纤维专用品种的选育方向。     

膳食纤维与人体健康

膳食纤维是包含纤维素、半纤维素、木质素、果胶及可溶性多糖等多种成分的混合物。膳食纤维具有多种生理保健功能，与人体健康密切相关，缺乏膳食纤维会引发多种疾病，所以含有膳食纤维的制品倍受消费者的青睐。     

碱法提取普洱茶渣膳食纤维的工艺优化

以普洱茶渣为原料,通过碱法提取茶渣中膳食纤维,研究影响因素（碱液浓度、碱解温度、碱解时间和料液比）对普洱茶渣中膳食纤维得率的影响。结合单因素和响应面试验得到最优提取工艺参数为碱液浓度3.35%、碱解温度100 ℃、碱解时间2.36 h、料液比1∶28（g/mL）。在该条件下,普洱茶渣中膳食纤维的得率为82.26%,较提取前极显著提高（P＜0.001）。提取后的茶渣膳食纤维中纤维素、半纤维素、木质素和果胶的含量分别为52.10%、14.20%、15.30%和5.00%,以不溶性纤维为主。     

EFFECT OF DIETARY FIBER ON THE PREVENTION OF LIVER LIPID ACCUMULATION INDUCED BY HIGH POLYUNSATURATED OIL

This study investigated whether dietary fiber can prevent the accumulation of liver lipids due to the ingestion of polyunsaturated oil. Fifteen percent fish oil (FO) was added to the basal diet as a source of polyunsaturated oil. Ten percent cellulose, pectin, guar gum, konjac mannan or gum Arabic was mixed in the diet as a source of dietary fiber. Commercial Purina rat chow was used as a control and a fiber-free (blank) diets were also employed in the study. Each experimental diet was fed to each group of 6 Wistar rats for 8 weeks. Fish oil feeding lowered the plasma triacylglycerols (TG) and cholesterol (CS) levels. Rats fed a fiber-free diet had higher liver weights indicating hepatomegaly and a marked accumulation of liver lipids. With the exception of cellulose and gum Arabic, the inclusion of dietary fiber in FO diets lowered the plasma total lipids and CS; plasma TG was unchanged. Pectin and guar gum enhanced the CS-lowering effect of the FO diet. All of the test fibers, but especially pectin and guar gum, reduced the accumulation of total lipids, TG and CS in rat liver caused by dietary FO. Hepatic glucose-6-phosphate dehydrogenase activity was reduced in rats fed FO, but dietary fiber had no effect on the activity of this enzyme.     

多功能大豆纤维影响小鼠排便功能及机理研究

0.5、0.8或1.2g/kg·d的多功能大豆纤维(MSF),可增加小鼠粪便排泄量及粪便含水量。当MSF剂量增加时粪便排泄量随之增加,但粪便含水量无明显变化。0.8g/kg·d小麦纤维的作用相似,而同剂量的果胶也可明显提高粪便含水量,但对粪干质量无明显影响。水溶性纤维的持水力高,易被大肠微生物所降解,对增加粪便水分含量的效果较好,但对增加粪干质量的效果较差;水不溶性纤维的作用恰好相反。     

In Vitro Fermentabilities of Purified Fiber Supplements

Six commonly used dietary fiber supplements (pectin, tragacanth gum, psyllium gum, guar gum, soy fiber and cellulose) were fermented in vitro with human fecal microbiota for 4, 8,12, and 24 hr. Short chain fatty acids (SCFA), hydrogen and methane productions, and neutral-detergent fiber digestibility differed significantly with fiber source. The most rapid fermentation rate was with pectin followed by psyllium gum, tragacanth gum, guar gum, soy fiber, and finally cellulose. Such differences in fermentability should be considered when food products are formulated. Dietary fiber source and intake may also affect breath hydrogen measurements and estimates of available carbohydrate malabsorption.     

Effect of pH and Heat Treatment on the Binding of Calcium, Magnesium, Zinc, and Iron to Wheat Bran and Fractions of Dietary Fiber

The effect of pH and heat treatment on the binding of added food grade sources of calcium, magnesium, zinc, and iron to a standard wheat bran, cellulose, and lignin was investigated. 1% solutions of pectin and guar gum were examined for their ability to bind these metals in aqueous solution. Lignin and pectin was found to have high metal binding capacities. Metal binding to fiber was found to be pH dependent. Toasting had no effect on metal binding by cellulose, but had a significant effect on the binding of metals by lignin and wheat bran. Boiling had a significant effect on the binding of metals by cellulose, lignin, and wheat bran.     

Effect of guar gum on the serum lipid profile of Sprague Dawley rats

The aim of the study was to probe the hypocholesterolemic effect of legumes dietary fiber through “chapaties” a staple diet of the South Asia. Commercial wheat flour (atta) was blended with legumes i.e. lentil, chickpea and guar gum in various combinations to make composite flour for the preparation of chapaties. Maximum dietary fiber (8.85%) was observed in composite flour with 3g/100 g guar gum, which also gave whiter look and puffiness to the end product. Highest percent increase in dietary fiber (35.3%) was in flour with 3g/100 g guar gum followed by guar gum 2g/100 g (24.1%). The diets prepared from three best selected compositions along with control, were fed to male Sprague Dawley rats for 8 weeks. Lowest serum cholesterol (82.46 mg/dl) was observed in rats fed on guar gum 3g/100 g which showed a significant reduction (17.2%) as compared to control. Similarly, in case of LDL and triglycerides, guar gum 3 g/100 g showed highest decline i.e., 29.7% and 28.4% with reference to control, respectively. The present investigation suggests that five chapaties per day prepared from selected compositions provides an extra 5-8 g of dietary fiber that is helpful in lowering cholesterol in hypercholesterolemic individuals.     

复合膳食纤维素的结构及物性研究

采用大豆纤维素为基料,水溶性天然植物胶——瓜尔豆胶、果胶为辅料复合后,制备一种兼有水溶性和非水溶性双重特性的复合膳食纤维素。测定复合膳食纤雏素的粘度和表面张力,并对复合膳食纤维素体系进行扫描电镜观察后发现,大豆纤维素与瓜尔豆胶复合物的粘度和表面张力较两种单一成分均有明显提高,且复合物可调和成为以瓜尔豆胶溶胶为基体、大豆纤维素颗粒均匀镶嵌其间的稳定体系。大豆纤维素与果胶复合物的上述指标也有提高,但体系不稳定。     

湿热-胶体改性对小麦面筋蛋白功能性质的影响

研究了在湿热条件下将羧甲基纤维素钠(CMC)、明胶、海藻酸钠、果胶、瓜尔胶这几种不同胶体作为添加剂添加到小麦面筋蛋白中,测定了其对小麦面筋蛋白功能性质的影响,主要以小麦面筋蛋白的粘稠性、乳化性和乳化稳定性、溶解性、起泡性这几个指标作为参考。实验结果表明,与简单混合相比,羧甲基纤维素钠、明胶、海藻酸钠、果胶在湿热条件下使小麦面筋蛋白的溶解性,乳化性和粘稠性都有一定幅度的提高,但是对小麦起泡性和乳化稳定性的影响不大;瓜尔胶在湿热条件下对小麦蛋白性质的影响与简单混合相比基本持平。