Bioactivities of Pseudocereal Fractionated Seed Proteins and Derived Peptides Relevant for Maintaining Human Well-Being

Food proteins and peptides are able to exert a variety of well-known bioactivities, some of which are related to well-being and disease prevention in humans and animals. Currently, an active trend in research focuses on chronic inflammation and oxidative stress, delineating their major pathogenetic role in age-related diseases and in some forms of cancer. The present study aims to investigate the potential effects of pseudocereal proteins and their derived peptides on chronic inflammation and oxidative stress. After purification and attribution to protein classes according to classic Osborne’s classification, the immune-modulating, antioxidant, and trypsin inhibitor activities of proteins from quinoa (Chenopodium quinoa Willd.), amaranth (Amaranthus retroflexus L.), and buckwheat (Fagopyrum esculentum Moench) seeds have been assessed in vitro. The peptides generated by simulated gastro-intestinal digestion of each fraction have been also investigated for the selected bioactivities. None of the proteins or peptides elicited inflammation in Caco-2 cells; furthermore, all protein fractions showed different degrees of protection of cells from IL-1β-induced inflammation. Immune-modulating and antioxidant activities were, in general, higher for the albumin fraction. Overall, seed proteins can express these bioactivities mainly after hydrolysis. On the contrary, higher trypsin inhibitor activity was expressed by globulins in their intact form. These findings lay the foundations for the exploitation of these pseudocereal seeds as source of anti-inflammatory molecules.     

一种苦荞冻凝胶食品的研究与开发

以苦荞茶和褐藻膳食纤维粉为主要原料,采用单因素试验和正交试验,结合质构仪测定指标和感官评价研制一种苦荞冻凝胶食品。以产品凝胶强度和感官得分为指标,通过单因素和正交试验优化出苦荞冻的最佳配方和制作工艺。结果表明,最佳配方为褐藻膳食纤维粉1.8%,成型剂添加量1.1%,苦荞茶汤添加60%(浸提比为1∶60)。按照此配方制作的产品具有很好的苦荞风味,凝胶强度和感官评分最高,具有很好的营养价值。     

荞麦降糖酸奶的研制

荞麦富含蛋白质、维生素、矿物质等众多营养物质,特别是生物类黄酮、手性肌醇、高活性蛋白等降糖因子的含量明显高于其它粮食作物。旨为糖尿病人群开发具有降糖作用的保健食品,使酸奶和荞麦得到更好的结合,以保加利亚乳杆菌和嗜热链球菌按l∶l混合作为生产茵种。采用单因素实验和正交实验对酸奶发酵工艺进行研究,实验结果表明,苦荞牛乳混合发酵酸奶的最佳工艺条件为苦荞浆添加量30%、木糖醇添加量8%。稳定剂添加复配比例CMC 0.15%、卡拉胶0.10%、黄原胶0.05%,菌种添加量3%,发酵时间4 h。同时在后熟过程中添加降糖因子,手性肌醇为6.55μg/mL,黄酮类化合物0.526 mg/mL,荞麦蛋白0.12 g/mL。     

荞麦壳色素的提取及对羊毛织物的染色性能

采用天然染料荞麦壳提取液对羊毛织物进行染色,通过响应面法得到优化的荞麦壳色素提取工艺:粉碎目数100目、提取温度100℃、提取时间144 min,色素的产率为4.36%。通过正交试验得到直接染色的优化工艺条件:染色pH值5、染色温度100℃、染色时间80 min。选择三种媒染方法和三种媒染剂分别对羊毛织物进行染色,测试染后织物K/S值、防紫外线性能及色牢度。结果表明,以硫酸铝钾作为媒染剂的后媒染工艺染得织物的K/S值较大,媒染剂的使用提高了织物的耐摩擦色牢度,降低了UVA、UVB的透过率。     

Antioxidant and radical-scavenging activities of buckwheat seed components

The search for endogenous components in food ingredients exhibiting antioxidant activity has been intensified in order to eliminate synthetic antioxidants. Tocopherols are widely used as natural antioxidants, although their protective ability is not always sufficient. Buckwheat seed components were evaluated for antioxidant and free radical-scavenging activities using solvents of different polarities to isolate components from hulls and groats. Components extracted from buckwheat hulls were pro-oxidant in canola oil. Antioxidant activity of extracts from buckwheat groats increased when more polar solvents were used for extraction. The highest activity was observed for the methanolic extract. Radical-scavenging activity of buckwheat extracts was analyzed with DPPH (2,2-diphenyl-2-picryl-hydrazyl). This activity increased when the more polar solvents were used for extraction, with the highest activity observed for the methanolic extract. It was also observed that the radical scavenging effectiveness of extracts was concentration dependent. Analysis revealed the presence of tocopherols in the hexane extract, while methanolic extracts were rich in phenolic acids and flavonoids.     

荞麦槲皮素对高脂饮食大鼠脂代谢及脂肪因子的调节作用

该文研究了荞麦槲皮素（QYE）对高脂饮食大鼠脂质代谢及脂肪因子的影响。将54只SD大鼠随机分为对照组、模型组、阳性组、荞麦槲皮素低（50 mg/kg）、中（100 mg/kg）、高（200 mg/kg）剂量组,建立高脂血症大鼠模型5周后,灌胃荞麦槲皮素干预治疗,测定各组大鼠血清、肝脏脂质水平,以及血清抗氧化、脂肪因子水平,并观察肝脏组织病理切片。结果表明,与模型组相比,荞麦槲皮素能够降低血清和肝脏TC、TG的含量,其中QUE高剂量组血清中TC、TG含量分别下降了33.47%和28.66%,较模型组差异极显著（P<0.01）;荞麦槲皮素高剂量组的Chemerin水平下降12.3%,CMKLR1水平下降19.83%,TLR4水平下降15.87%,NF-κB水平下降14.12%。同时荞麦槲皮素高剂量组上调了血清中33.87U/m L的GSH-Px酶活力,差异极显著（P<0.01）,荞麦槲皮素高剂量组下调了血清中79.56U/m L的CHE含量。由此可见,荞麦槲皮素能显著调节高脂膳食大鼠血脂异常,降低Chemerin及其受体CMKLR1、TLR4、水平,抑制NF-κB通路活化,减少...     

我国市场上荞麦挂面的品质分析

从市场采集42个荞麦挂面产品,对其品质指标进行分析研究,为《荞麦挂面》标准的制定提供数据支持。结果表明：采购的42个样品水分含量为9.07%~13.53%,74%样品的烹调损失率≤10.0%,煮熟增重率为93.2%~241.7%,熟断条率为0%~3.3%,均≤5.0%,自然断条率在0%~7.1%之间,95%样品的自然断条率≤5.0%。苦荞挂面中总黄酮含量为0.15%~1.94%,其他荞麦挂面中总黄酮含量为0.10%~0.55%。荞麦挂面的L*值为32.35~86.12,a*值为0.85~7.25,b*值为11.95~38.15。100%的荞麦挂面酸度值≤4.0 mL/10 g,储藏品质良好。     

基于响应面分析优化荞麦面条制备工艺

以小麦粉和荞麦粉为原料,选择荞麦粉和小麦粉质量比、谷朊粉添加量、黄原胶添加量及葡萄糖氧化酶添加量为单因素,蒸煮品质和感官品质为评定指标,在单因素的基础上,采用响应面分析法对荞麦面条制备工艺进行优化.试验结果表明荞麦面条最优制备工艺:荞麦粉和小麦粉质量比为32:68,谷朊粉添加量为5％,黄原胶添加量为0.2％,葡萄糖氧化...     

转谷氨酰胺酶对荞麦蛋白功能特性的影响

微生物转谷氨酰胺酶(MTGase)能够使荞麦蛋白(BWP)的大部分球蛋白亚基被聚合,而几乎不能使分子量低于36kDa的碱性亚基聚合。BWP聚合物(催化时间<60min)的溶解度(PS)较BWP显著增加,聚合物的PS随反应时间的延长而降低;MTGase催化BWP反应120min可明显降低其PS(P<0.05)。聚合反应能提高BWP的持水能力(WH)和持油能力(FA),且BWP聚合物的FA随反应时间的增加而增强。适当的交联会使BWP的起泡性能增加,但继续提高交联度(延长酶反应时间),BWP的起泡性能反而降低。BWP聚合物的乳化活性指数(EAI)降低,乳化液稳定性(ES)却增强。     

响应面法优化荞麦蜂花粉中黄酮类物质的提取

在单因素实验的基础上,采用响应面法的Box-Behnken进行实验设计,对荞麦蜂花粉中黄酮类物质的提取条件进行优化。研究表明,黄酮类物质的最佳提取条件为：提取剂80%乙醇,料液比1∶21.2,提取温度73.2℃,提取时间58.9 min,提取率为88.7%。