食物中蛋白质和碳水化合物对睡眠影响的研究进展

大量研究表明食物中常量营养素蛋白质和碳水化合物对睡眠有重要影响,但不同的研究所得结果不尽相同,因此尚不完全清楚食物中蛋白质和碳水化合物对睡眠究竟有何影响。本文结合国内外相关研究,对蛋白质和碳水化合物对睡眠的具体影响进行综述,发现高碳水化合物低蛋白质的食物可能有助于促进睡眠,改善睡眠质量。本文旨在从膳食营养素角度出发为改善睡眠提供一定的理论指导。     

Carbohydrates of rapeseed: A review

Graded extraction of oil-free, dehulled, rapeseed cotyledon meal with boiling aqueous ethanol, hot water, hot ammonium oxalate and finally sodium hydroxide yielded a series of fractions. The composition, identification and structural evaluation of the various products is presented and the results compared with those obtained from other seeds.     

Plant-Derived Supplementary Carbohydrates,Polysaccharides and Oligosaccharides in Management of Diabetes Mellitus: A Comprehensive Review

ABSTRACT

Background and aims: Diabetes mellitus is a chronic heterogenic disease characterized by the deregulation of the metabolism of insulin and glucose. The aim of this review has been to evaluate the efficacy of medical plant-based carbohydrates, excluding monosaccharides, to manage glycemic response in clinical trials.

Methods: The range of literature presented was compiled by searching electronic databases, including Scopus, PubMed and Cochrane library, from their inception through to June 2018. Only clinical-based studies were considered for this review. Dietary carbohydrates were investigated, especially those containing fiber possessing beneficial effects in the management of hyperglycemia. The most common oligosaccharides, including xylooligosaccharide, isomaltooligosaccharide, fructooligosaccharide, galactooligosaccharide, and sucrose, were able to manage glycemic and insulin metabolism in clinical trials.

Results: In light of 77 selected papers, several plant-based oligosaccharides and polysaccharides have been shown to significantly improve the management of glucose and insulin metabolism in healthy and diabetic patients.

Conclusions: Oligosaccharides and polysaccharides derived from plants possess promising hypoglycemic potential, similar to and even more effective than current synthetic drugs, with no deleterious side effects.

Abbreviations: AMPK: AMP-activated protein kinase; AX: Arabinoxylan; CAT: Catalase; CFDA: Chinese food and drug administration; DM: Diabetes mellitus; FBS, Fasting blood glucose; FDA: United States food and drug administration; FOS: Fructooligosaccharide; G6Pase: Glucose-6- phosphatase; GCK: glucokinase; GD: Gestational diabetes; GI: Glycemic index; GL: Glycemic load; Glut4: Glucose transporter 4; GOS: Glucooligosaccharide; GPx: glutathione peroxidase; GRAS: generally regarded as safe HCF: high-carbohydrate, high fiber diet; HNF1α: Hepatic nuclear factor 1 alpha, HNF4α: Hepatic nuclear factor 4α; HNF1β: Hepatic nuclear factor 1β; II: Insulinemic index; IOS: Isomaltooligosaccharides; KGM: Konjac glucomannan; LBP: L. barbarum polysaccharide; MODY: Maturity onset diabetes of the young; PECK: phosphoenolpyruvate carboxykinase; RDS: Rapidly digestible starch; RS: Resistant starch; SBOS: Soybean oligosaccharides; SDS: Slowly digestible starch; SNP: Single nucleotide polymorphism; SOD: Superoxide dismutase; T1DM: Type 1 diabetes; T2DM: Type 2 diabetes mellitus; TBARS: Thiobarbituric acid reactive substances; XOS: Xylooligo-saccharide.     

氧脱木素过程中氧自由基的产生及其脱木素选择性

氧脱木素是一个包含有多种活性氧参与的复杂的反应过程.O2在木素、碱液以及金属离子的共同作用下逐步被还原为O2、HO、H2O2等活性氧.HO?与O2?是氧脱木素过程中两种主要自由基,在脱木素过程中发挥协同作用使得木素大分子降解并溶出.氧脱木素选择性由碳水化合物的降解程度以及木素脱除率决定.HO?的强氧化性是造成碳水化合物降解的主要原因;联苯结构、对羟基苯结构等"惰性"木素单元不易降解溶出以及LCC连接、碳水化合物的结晶结构对O2及氧自由基的阻碍作用,是限制木素脱除的主要原因.     

类胡萝卜素肠道吸收及生物利用度研究进展

类胡萝卜素是一种广泛存在于果蔬中的脂溶性色素,在预防疾病和保护人体健康方面发挥重要功能,但是人体无法合成类胡萝卜素,只能从食物中摄取,且由于类胡萝卜素的溶解性差、不稳定等原因,其生物利用度通常非常低。本文简述类胡萝卜素的消化过程,以SR-B1、CD36、NPC1L1等肠道转运蛋白为重点,介绍类胡萝卜素在小肠上皮细胞的吸收,并从类胡萝卜素的亲脂性与化学存在形式、食物基质、胃肠道消化、宿主因素及肠道转运蛋白的表达或活性等方面出发,综述影响类胡萝卜素生物利用度的因素。     

稻米碳水化合物消化速度影响因素的研究进展

体外模拟碳水化合物消化速度的方法可以很好地预测食物的血糖反应,本文对有关研究的数据加以总结,并分析了影响稻米碳水化合物消化速度的因素,包括稻米的淀粉组成、理化特性以及品种和加工、储藏等方面.     

果酸钙和其它钙源对预防骨质疏松症的比较研究

在10000年前的农业时代初期，人类学就认为人类一直是钙的高吸收者。如果现代人类与旧石器时代人类的基因完全相同，则现代人类饮食中的钙只能被吸收三分之一，钙撮入量明显不足，满足不了人体的生理需求。对钙和骨质的分析研究表明：青少年、成年人、老人以及绝经后的女性每日撮入500-1500mg钙有利于骨质生长。由于果酸钙具有较高的生物吸收利用性，已成为当前钙研究的主题。果酸钙对青春期女孩、青年和绝经后妇女都起了积极的作用，而且微量元素和Vo的存在更有利于人体增强骨密度，降低骨折发生率。     

食品中钙吸收的机理与钙体外转化新方法探讨

人类缺钙的主要原因是钙的吸收率低。食品中的钙通过消化过程在胃部与体内所含氨基酸发生反应,吸收方式为氨基酸螯合钙;此吸收过程中的影响因素主要为VD,蛋白质和氨基酸的含量等。钙的转化通过人体体内代谢过程调节较为缓慢且难以控制,因此提出将钙以易于吸收的方式富集在人类日常食用的食品当中显得尤为重要。     

肠道转运蛋白P-糖蛋白对药物吸收的影响

P-糖蛋白是一种膜转运蛋白,可将药物由胞液泵出胞外,从而降低了药物的生物利用度.现将P-糖蛋白影响药物吸收的特点及相关内容作一论述.     

肠道转运蛋白P-糖蛋白对药物吸收的影响

P-糖蛋白是一种膜转运蛋白,可将药物由胞液泵出胞外,从而降低了药物的生物利用度.现将P-糖蛋白影响药物吸收的特点及相关内容作一论述.     

动物吸收类胡萝卜素的肠道内环境控制研究

本研究证明了类胡萝卜素在肠道内的被动吸收机制，对不同动物肠道内环境进行了检测，结果表明不同动物的肠道内环境有较大的差异。对差异较大的因素（如pH值、胆盐浓度、游离脂肪酸等）进行了．系列的研究，发现这些因素对动物吸收β-胡萝卜素有明显的影响。因此首次提出了肠道内环境控制动物吸收胡萝卜素的假说。     

Lignin Effect on Calcium Absorption in Rats

The effect of lignin on calcium absorption was studied in a rat model. Lignin preparations were isolated directly from wheat bran and from kale by two treatments, enzymatic and acidic. Calcium absorption in the presence or absence of isolated wheat bran lignin, isolated kale lignin, commercially available pine lignin, and wheat bran was determined by femur uptake of 45Ca. The fractional calcium absorption of wheat bran was significantly lower than for the control. However, there were no differences in calcium absorption between the various lignin sources and the control without lignin. Thus, lignin is probably not inhibitory to calcium absorption in plant foods.     

姜黄素固体脂质纳米粒在大鼠体肠中吸收的研究

采用乳化-超声法制得姜黄素固体脂质纳米粒(Curcumin solid lipid nanoparticles,CNSLN),比较游离药姜黄素(Curcumin,CRM)和CNSLN的在体肠中吸收情况。选用大鼠在体单向肠灌流模型(Single-pass intestinal perfusion model,SPIP),以紫外分光光度法测定游离CRM和CNSLN通过肠液后CRM的减少量来确定药物的吸收。结果:透射电镜下观察到CNSLN成圆形或椭圆形,平均粒径为(120.7±5.4)nm,平均Zeta电位为(-41.90±1.81)m V,平均包封率为(91.12±0.42)%。游离CRM和CNSLN在十二指肠、空肠、回肠和结肠4段的吸收速率常数(Ka)、有效渗透率(Peff)和百分吸收率(W)均存在显著性差异(P0.01),CNSLN比游离CRM均提高了2倍以上,且CNSLN的最大吸收部位在结肠。在体肠吸收结果显示,CNSLN的肠吸收比游离CRM高,CNSLN能明显的提高大鼠对游离CRM的肠吸收。     

肠类器官应用于营养素吸收的研究进展

肠道不仅是营养物质消化吸收的主要部位,也是重要的免疫器官和内分泌器官。营养物质在肠道内的消化吸收状况是决定其高效利用的重要因素。构建适宜的体外肠道模型对明确营养物质的有效吸收部位、吸收效率及机制具有重要意义。类器官由于可高度模拟目标组织或器官的遗传特性和表观特征被广泛应用于各个领域。本文综述了近年来肠类器官在营养物质消化吸收方面的研究进展,以期为肠类器官在营养物质的消化吸收中的广泛应用提供参考。     

虾壳中复合钙粉的制备工艺优化及大鼠对其吸收效果的评价

为研究虾壳中复合钙粉的制取工艺及评价大鼠对其吸收效果,以南美白对虾虾壳为研究对象,采用胰蛋白酶-柠檬酸法制取钙粉,进而以缺钙为模型研究大鼠对复合钙粉的吸收效果。结果表明：采用胰蛋白酶-柠檬酸制取复合钙粉的最佳工艺为加酶量2.5×103 U/g、酶解pH 8.0、酶解时间1.5 h、酶解温度45 ℃,此时,蛋白水解度为57.24%;柠檬酸浓度0.35 mol/L、柠檬酸用量20 mL、处理时间1.5 h时,钙溶出率为85.78%;制取的复合钙粉中钙含量为19.6%,总氨基酸含量为18.3%。复合钙粉质地细腻,呈淡褐色,无异味。动物实验表明,从虾壳中制取的复合钙粉的大鼠钙吸收效果显著（P＜0.05）,灌胃剂量66.5 mg/（kg•d）（以钙含量及大鼠体质量计）的复合钙粉能明显提高大鼠血清钙、磷水平,促进大鼠正常生长。胰蛋白酶结合柠檬酸能有效地从虾壳中制取复合钙粉,其吸收效果优于相同钙含量的碳酸钙。     

植物多糖结构类型及对肠道微生态影响研究进展

多糖是植物中主要的功能活性物质,具有抗氧化、免疫抗炎、抗肿瘤、保肝、降脂、调节肠道菌群等生物活性。该文对植物多糖不同结构类型及对肠道微生态影响方面的研究进行综述,为植物多糖进一步作为功能性食品的开发与利用提供重要的理论依据。     

类胡萝卜素肠道吸收与代谢的影响因素研究进展

类胡萝卜素是类异戊二烯单元组成的一类萜类色素,在维持眼部健康、提高免疫力等方面具有重要作用。人体不能合成这种色素,必须从膳食中摄取。人体摄入后,类胡萝卜素会经历复杂的消化吸收与代谢过程,并受到食物本身以及人体内环境等多种因素的影响。肠道是类胡萝卜素吸收、代谢最重要的场所。本文综述化合物结构、膳食因子、加工方式、包埋、转运蛋白、生物裂解酶等因素对类胡萝卜素在肠道吸收、代谢的影响,并探讨肠道菌群在其中发挥的作用,为类胡萝卜素体内的吸收与生物转化研究提供参考。     

Intestinal Absorption of Lycopene from Different Types of Oleoresin Capsules

ABSTRACT: After a 2-wk depletion period, 24 volunteers, divided into 3 groups, ingested 5 mg/d lycopene for 4-wk from 5 capsules containing tomato oleoresin or synthetic lycopene. Plasma samples were analyzed on carotenoids using C₁₈ HPLC with diode array detection. Basal lycopene levels (0.19 to 0.31 μmol/L) in plasma of the 3 groups were in a comparable range (p > 0.05) and significantly decreased after the 2-wk diet low in lycopene to 21 to 52 % of the basal values. Four out of 5 investigated capsules significantly (p < 0.05) enhanced the plasma lycopene levels relative to the depleted state after 1 wk of supplementation to 0.20 to 0.27 μmol/L. Increasing the surface of lycopene crystals by reducing the particle size was the most effective processing step to enhance intestinal absorption of lycopene. However, presence of tomato oil in oleoresin and partly removal of selective fatty acids affected the intestinal absorption of lycopene, too.