The polysaccharide of green coffee beans from Yunnan Coffea arabica was purified by Sevag method,macroporous resin,cellulose column,and gel separation technology,respectively.The purification effect of green coffee beans polysaccharide was compared by determining the content changes of polysaccharide,uronic acid,protein,total phenols and total flavonoids in the sample.The structural characteristics of the green coffee beans polysaccharide was characterized by Fourier Transform Infrared spectroscopy(FTIR)and scanning electron microscope(SEM).Moreover,the antioxidant capacity of the green coffee beans polysaccharide was evaluated by DPPH radical scavenging assay and FRAP method.The results showed that purified polysaccharides had many irregular hollows,and the protein,total polyphenols,total flavonoids,and uronic acid contents decreased.The results of antioxidant assays showed that polysaccharides of green coffee beans had a certain antioxidant activity.IC50 value of DPPH radical scavenging capacity was 2.843 mg/mL.The ferric reducing antioxidant power was 0.333 mmol Fe2+/g RP.Therefore,polysaccharides of green coffee beans have certain antioxidant capacity and have potential value for further development as natural antioxidants.
The purpose of this study is to screen excellent probiotics with hypoglycemic ability in human milk,and lay a foundation for developing probiotic dairy products with hypoglycemic function. The strains were isolated and purified by dilution coating method to identify strains with α-Glucosidase and α-amylase inhibitory activity. A total of 21 probiotics were obtained from human milk,15 of which were identified as Lactobacillus plantarum,3as Lactobacillus reuteri,and 3 as Lactobacillus formosanus. For R15 and R17,the inhibition rate of glucosidase reached 12.73% and 13.83%,respectively. For R15 and R7,the inhibition rate of amylase reached 88% and 89.3%,respectively. For commercial bacteria Lactobacillus reuteri 254474,α-glucosidase and α-amylase inhibition rates were only 11.4% and 80%,respectively. This indicates that Lactobacillus plantarum R15 has the best hypoglycemic ability,and can be a potential strain in the future functional dairy products development.
β-胡萝卜素是人体不可缺少一种天然色素,具有抗氧化、抗癌、抗心血管疾病等功能活性,但极性较低且极易氧化,这使得其在食品体系中的应用与消化吸收具有挑战性,利用乳液体系将其包埋是解决上述问题的有效方法.油脂体作为植物种籽细胞中贮藏甘油三酯的特殊细胞器,具有"单层磷脂嵌套蛋白-油脂"的"膜-核"结构,是天然存在的乳化后的油滴,适宜作为水包油乳液的分散相.本研究采用微热搅拌和层层自组装相结合的方法,利用天然油脂体负电与壳聚糖正电性,将β-胡萝卜素包裹在壳聚糖-菜籽油脂体乳液中,并实现了对其稳定性、包埋性的提高,产生了较小粒径的高电荷阳离子乳液(d3,2 = 2.25 μm;ζ =+66.67 mV).类胡萝卜素的包封率为81.98%,载药量为 1.23 mg/g 油脂体;本研究结果为开发纯天然乳液递送体系的理论与应用创新提供了参考.
研究不同产地的丁香花蕾油的生物活性成分鉴定及其抗氧化性影响.采用重油提取器提取产自广东、印度尼西亚、坦桑尼亚和马来西亚的丁香花蕾油样品,并进行香气评吸,采用GC-MS法鉴定其主要成分及其相对含量,用DPPH自由基分析法测定其抗氧化活性.香气评吸结果为印度尼西亚丁香花蕾油最佳;DPPH自由基实验结果显示为各个产地的丁香花蕾油都有较好的清除自由基能力,其中印尼丁香花蕾油清除自由基效果最好;根据GC-MS分析谱图,得出挥发油的成分主要为丁香酚和丁香烯,两者含量之和达到90%以上,印尼丁香花蕾油的主要成分之一为约5%的 3-甲氧基苯乙酮,与其他三种丁香花蕾油成分不同.由上述结果得出丁香花蕾油优选产地为印度尼西亚.本研究为丁香花蕾油的应用提供更多的理论依据.
番茄红素是一种脂溶性功能性色素,其分子式为 C40H56,是一种直链碳氢化合物.研究发现番茄红素在抗氧化、保护神经系统、延缓衰老、抑制肿瘤、降低心血管疾病发病率、减少肝损伤、提高人体免疫力和延缓骨质疏松等多个方面均具有较好的保健作用,是一种很有发展前景的新型功能性天然色素.番茄红素的功能性及保健作用的研究一直以来都是医药保健营养食品开发领域的研究热点,本文结合全球新品开发的应用前景及发展趋势,对番茄红素产品的新产品上市趋势及现行相关法规状况进行分析,为后续食品及新型医药保健产品的开发提供借鉴和参考作用.
