蓝莓花青素的提取工艺条件

以蓝莓果为原料采用乙醇浸提法提取花青素,确定的最佳提取条件为pH 3.5、浸提温度50℃、浸提60 min,浸提剂乙醇浓度为50%,提取1次.该条件下提取率为5.8%.     

红莓果中花青素的提取工艺研究

以HCl-乙醇为溶剂,研究了红莓果中花青素的最佳提取工艺。在单因素试验中,选择了单次提取和2次提取,分别测定了不同提取级数下各因素(物料比、提取时间、提取温度)的最佳水平值。同时,以果实中花色苷的绝对含量作为提取效率的评价标准,提高了单纯采用吸光度值测定法作为评定指标的精确性与可靠性。通过响应面试验确定了最佳的提取工艺参数为:浓度为1.5 mol/L的HCl和体积分数95%的乙醇(体积比15∶85)为溶剂,提取料液比为5 g∶1 mL,提取时间为53 min,提取温度为71℃,提取2次。依此工艺,红莓花青素的提取得率为36.39 mg/100 g(鲜果)。     

石榴汁花青素的制备与稳定性研究

研究了石榴汁花青素的稳定性，结果表明：石榴汁花青素的最大吸收波长λmax=516nm；温度对该色素有一定的降解作用，在加工中热处理温度应不高于60℃;pH对该色素的影响明显，宜在酸性食品中应用；柠檬酸对该色素有一定的增色作用；蔗糖、葡萄糖、紫外光照射对该色素影响作用很小；低浓度的苯甲酸钠和山梨酸钾对该色素无影响，高浓度的则有降解作用；而H2O2、Na2SO3、VC和O3则对该色素有破坏作用。     

新疆小檗属果实花色苷成分的初步鉴定

以新疆南疆小檗属植物——喀什小檗、红叶小檗和黑果小檗的果实为实验材料.采用光谱法和纸色谱法对其花色苷的成分进行了初步鉴定.结果表明:喀什小檗果实中花色苷为矢车菊色素,在C3位带有葡萄糖或是半乳糖糖苷.红叶小檗果实中花色苷为天竺葵色素和锦葵色素,在C3位带有葡萄糖或是半乳糖的酰化基团.黑果小檗果实中花色苷为天竺葵色素,在C3或是C7位带有葡萄糖或是半乳糖的酰化基团.     

不同品种彩色马铃薯总花色苷含量与总抗氧化活性

以10 个彩色马铃薯品种为实验材料,采用pH示差法测量其总花色苷含量、1,1-二苯基-2-三硝基苯肼（2, 2-diphenyl-1-picrylhydrazyl,DPPH）法分析其总抗氧化活性,比较不同品种的彩色马铃薯的总花色苷含量和总抗氧化活性。结果表明：不同品种的彩色马铃薯的表皮、薯肉、整薯总花色苷含量的变化范围分别为59.67～293.57 mg/100 g、0～56.11 mg/100 g、1.34～63.32 mg/100 g;表皮、薯肉、整薯抗坏血酸当量（ascorbic acidequivalent antioxidant capacity,AEAC）的变化范围分别为2.74～6.43 mg/g、0.50～1.39 mg/g、0.65～1.50 mg/g。其中,紫云1号的总花色苷含量和总抗氧化活性均为最高;S05-603的总花色苷含量最低;S03-2677的总抗氧化活性最低。此外,整薯总花色苷含量与总抗氧化活性的正相关性极显著（P＜0.01）。     

二次正交旋转组合设计优化药桑花青素提取工艺

在超声波辅助条件下,采用四元二次正交旋转组合设计研究乙醇体积分数、液料比、时间、温度4个因素对药桑花青素提取效率的影响,用DPS7.05软件分析得出4个因素的回归方程。结果表明,超声波辅助提取最佳工艺条件为：乙醇体积分数范围52.46%～55.93%、提取液料比范围39.51:1～42.43:1(mL/g)、提取时间范围27.77～32.23min、提取温度范围50.18～52.4℃,在此工艺条件下花青素提取效率均能达到67%以上。     

Fermentation, degradation and microbial nitrogen partitioning for three forage colour phenotypes within anthocyanidin-accumulating Lc-alfalfa progeny

BACKGROUND: Alfalfa has the disadvantage of having a rapid initial rate of protein degradation, which results in pasture bloat, low efficiency of protein utilisation and excessive nitrogen (N) pollution into the environment for cattle. Introducing a gene that stimulates the accumulation of monomeric/polymeric anthocyanidins might reduce the ruminal protein degradation rate (by fixing protein and/or direct interaction with microbes) and additionally reduce methane emission. The objectives of this study were to evaluate in vitro fermentation, degradation and microbial N partitioning of three forage colour phenotypes (green, light purple‐green (LPG) and purple‐green (PG)) within newly developed Lc‐progeny and to compare them with those of parental green non‐transgenic (NT) alfalfa. RESULTS: PG‐Lc accumulated more anthocyanidin compared with Green‐Lc (P < 0.05), with LPG‐Lc intermediate. Volatile fatty acids and potentially degradable dry matter (DM) and N were similar among the four phenotypes. Gas, methane and ammonia accumulation rates were slower for the two purple‐Lc phenotypes compared with NT‐alfalfa (P < 0.05), while Green‐Lc was intermediate. Effective degradable DM and N were lower in the three Lc‐phenotypes (P < 0.05) compared with NT‐alfalfa. Anthocyanidin concentration was negatively correlated (P < 0.05) with gas and methane production rates and effective degradability of DM and N. CONCLUSION: The Lc‐alfalfa phenotypes accumulated anthocyanidin. Fermentation and degradation parameters indicated a reduced rate of fermentation and effective degradability for both purple anthocyanidin‐accumulating Lc‐alfalfa phenotypes compared with NT‐alfalfa. Copyright © 2012 Society of Chemical Industry     

花青素纳米载体的研究进展

花青素是一种黄酮类的水溶性天然色素,具有抗氧化、抗癌、抗炎、抗菌、降血糖等生理活性。然而,在加工和贮存过程中,不同环境条件下花青素的稳定性较低,容易发生降解。以脂类、多糖和蛋白质为材料制备的纳米载体具有良好的生物相容性、生物降解性和无毒性,能显著提高花青素的稳定性、生物活性和生物利用度。本文综述了近年来载花青素的纳米脂质体、生物大分子纳米载体和纳米乳液的制备技术及其在提高花青素理化稳定性方面的应用,并对花青素纳米载体的未来发展趋势进行了展望。