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排序方式: 共有679条查询结果,搜索用时 31 毫秒
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目的 探究安庆地区5个高产蓝莓品种(奥尼尔、灿烂、海岸、巴尔德温、密斯蒂)花青素稳定性。方法 以花青素保存率为评价指标,分别研究了环境因素(pH、光照、温度)和添加物(金属离子、氧化剂、还原剂、蔗糖、氯化钠、柠檬酸、山梨酸钾)对5个品种蓝莓花青素稳定性的影响。结果 5个品种蓝莓花青素对pH、光照和高温比较敏感; Zn2+、蔗糖、柠檬酸、山梨酸钾能增强花青素稳定性;花青素与Cu2+、Ca2+共存超过5 d,降解速度加快; Fe3+、H2O2、Na2SO3和浓度高于5%的氯化钠能破坏花青素的稳定性。结论 奥尼尔蓝莓花青素稳定性最弱,巴尔德温蓝莓花青素稳定性最强。研究结果可以为蓝莓花青素的加工与保藏提供参考。 相似文献
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采用双侧海马CA1区注射Aβ42构建阿尔茨海默症(Alzheimer′s disease,AD)动物模型,通过穿梭箱被动回避记录行为学数据;以大鼠血清和脑组织中的总超氧化物歧化酶(T-SOD)、过氧化氢酶(CAT)活力及还原型谷胱甘肽(GSH)、丙二醛(MDA)和蛋白质羰基(PC)含量作为评价指标,分析黑果枸杞花青素(OPC)样品对AD模型大鼠记忆力以及体内抗氧化活性的影响。结果表明,模型组动物的记忆能力显著下降,而黑果枸杞花青素组可改善AD模型大鼠的记忆损伤;同时,发现灌胃剂量为80 mg/kg的黑果枸杞花青素组能显著提高AD大鼠血清和脑组织中T-SOD、CAT活力和GSH含量,并降低MDA和蛋白质羰基含量水平。综合上述结果可知,本研究所述黑果枸杞花青素具有良好的增强体内抗氧化活性和提高AD大鼠记忆力的作用,并具有预防AD的潜在功效。 相似文献
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龙陵紫皮石斛色素的提取及其稳定性 总被引:1,自引:0,他引:1
以3 种类型的龙陵紫皮石斛(Dendrobium devonianum)茎为试材,用溶剂法提取色素,并研究其稳定性。结果表明:3 种类型龙陵紫皮石斛色素溶液在可见光533.0 nm波长处有吸收峰,其色素的主要成分为花色苷。紫鞘型、紫条型和血草型紫皮石斛花色苷含量分别为39.65、35.05、15.85 mg/L。温度的改变对紫皮石斛花色苷影响较大,随着温度升高,颜色逐渐加深;在阳光照射下,花色苷极不稳定,Mg2+和Al3+对花色苷有很好的增色、稳定作用;Cu2+、Zn2+和Fe3+使花色苷明显褪色,并伴有沉淀;随着H2O2 和VC、Na2SO3浓度的增大,颜色逐渐消退;食盐对紫皮石斛花色苷有一定的增色作用;蔗糖和柠檬酸使花色苷明显褪色。 相似文献
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目的:研究牛血清白蛋白(bovine serum albumin,BSA)与花青素相互作用形成的纳米颗粒的特性,及其对花青素的氧化稳定性的影响。方法:采用扫描透射电子显微镜和纳米粒度仪,研究BSA与笃斯越橘花青素形成纳米颗粒的表观形态及粒径大小,用盐析法测定BSA对花青素的结合量,并用自由基(DPPH自由基、ABTS+·)清除方法和胃肠模拟体系分别研究BSA对花青素氧化稳定性的影响。结果:BSA-花青素在磷酸盐缓冲液(pH 7.4)中能通过自组装形成纳米颗粒,其纳米颗粒较BSA的粒径变小,由30~35 nm减小到15~20 nm。BSA对花青素的结合量是每摩尔BSA分子上结合的花青素为10 mol。BSA-花青素纳米颗粒较花青素的DPPH自由基、ABTS+·清除能力明显增强。在胃模拟体系中,BSA与花青素结合对花青素稳定性没有显著性影响;在肠模拟体系中,BSA与花青素结合对花青素稳定性有显著性影响,未结合的花青素在6 h后含量降低70%左右,而有BSA结合的花青素含量几乎保持不变,表明BSA与花青素结合对花青素的氧化稳定性有明显的保护作用。 相似文献
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E. REVILLA E. GARCÍA-BENEYTEZ F. CABELLO 《Australian Journal of Grape and Wine Research》2009,15(1):70-78
Background and Aims: Different clones with distinctive enological characteristics have been identified in many grape cultivars, but data on differences in anthocyanin composition of clones of the same cultivar are scarce. Thus, it has been considered of interest to check changes in the anthocyanin fingerprint of six different clones of Tempranillo grapes grown in the same vineyard, and of wines made with them, over three consecutive years.
Methods and Results: Data were submitted to different statistical procedures. Despite slight differences in the anthocyanin fingerprint of some clones (relative content of different anthocyanins analysed), variations from year to year were more important than differences in the anthocyanin profile of the clones considered. This fact was also observed when the content (mg/kg grapes) of those molecules was considered. Moreover, Tempranillo wines made with different clones could be classified by discriminant analysis, using the anthocyanin fingerprint or the levels (mg/L wine) of several anthocyanins as predictor variables, and the year grapes were collected as a classification factor.
Conclusions: The anthocyanin fingerprint of six clones of Tempranillo grapes grown in the same vineyard and that of wines made with them over three consecutive years was affected mostly by weather conditions, despite slight differences in the anthocyanin fingerprint of some clones.
Significance of the Study: This is the first report on the anthocyanin composition of different clones of Tempranillo grapes and of wines made with them, and indicates that anthocyanin fingerprint of Tempranillo wines depends mainly on agroclimatic factors, and not on genetic differences among clones. 相似文献
Methods and Results: Data were submitted to different statistical procedures. Despite slight differences in the anthocyanin fingerprint of some clones (relative content of different anthocyanins analysed), variations from year to year were more important than differences in the anthocyanin profile of the clones considered. This fact was also observed when the content (mg/kg grapes) of those molecules was considered. Moreover, Tempranillo wines made with different clones could be classified by discriminant analysis, using the anthocyanin fingerprint or the levels (mg/L wine) of several anthocyanins as predictor variables, and the year grapes were collected as a classification factor.
Conclusions: The anthocyanin fingerprint of six clones of Tempranillo grapes grown in the same vineyard and that of wines made with them over three consecutive years was affected mostly by weather conditions, despite slight differences in the anthocyanin fingerprint of some clones.
Significance of the Study: This is the first report on the anthocyanin composition of different clones of Tempranillo grapes and of wines made with them, and indicates that anthocyanin fingerprint of Tempranillo wines depends mainly on agroclimatic factors, and not on genetic differences among clones. 相似文献