初冬银杏叶总黄酮超声浸取工艺优化

超声辅助浸提初冬银杏叶总黄酮,考察超声浸提时间、乙醇浓度、水浴温度、浸提次数对银杏叶总黄酮浸提的影响,并对试验结果进行验证.结果表明,初冬银杏叶总黄酮超声浸取的最佳工艺为:料液比1∶20,45 ℃水浴中60%的乙醇超声浸提20 min,共浸提3次,测得浸提液中银杏叶总黄酮含量为22.35 mg/g.验证性试验结果表明此工艺稳定,重复性好,回收率高,简单可行,省时,节能,可为工厂化浸提初冬季节银杏叶总黄酮提供技术参考.     

沙棘叶中总黄酮提取纯化工艺研究

[目的]建立沙棘叶中总黄酮的最佳提取纯化工艺。[方法]采用正交设计试验,以高效液相色谱图中主要化学成分的峰面积为指标,考察提取温度、提取料液比、乙醇浓度对沙棘叶中总黄酮提取率的影响。[结果]确定沙棘叶中总黄酮的最佳提取条件为A3B2C2,即提取温度60℃、料液比1∶10(g∶m L)、乙醇浓度60%;固定超声功率60 Hz,时间30 min,连续提取2次。[结论]该提取工艺黄酮提取率高,质量易于控制,为沙棘中黄酮类成分的提取和测定提供依据。     

荞麦总黄酮提取工艺研究

[目的]优选提取荞麦粉总黄酮的工艺条件。[方法]在标准液的制备及标准曲线的制作基础上,选用4个试验因素(浸提温度、乙醇浓度、浸提时间及乙醇用量)进行3水平正交试验优选,确定提取荞麦总黄酮的最佳工艺参数。[结果]4种因素对荞麦粉中总黄酮提取结果影响依次为:提取时间>提取温度>乙醇浓度>乙醇用量;总黄酮提取的最佳工艺条件为:10倍体积的75%乙醇溶液在65℃下浸提4 h。在此工艺条件下,荞麦总黄酮得率平均为2.91%。荞麦总黄酮的加样回收率为97.41%,RSD为0.847 2%,其吸光度在1 h内稳定,操作过程不影响测定结果。[结论]该试验优选的提取工艺结果重复性好,回收率高,简单可行。     

微波辅助提取杏花总黄酮工艺的研究

[目的]研究杏花总黄酮的微波辅助提取工艺条件.[方法]通过单因素试验和正交试验,探讨乙醇浓度、料液比、提取时间、提取功率、提取温度对杏花总黄酮提取效果的影响.[结果]各因素对杏花总黄酮提取效果影响的次序为:乙醇浓度>提取时间>提取温度>料液比.试验中最佳提取工艺条件为:乙醇浓度40;,提取时间8 min,提取温度70℃,料液比1:80.[结论]优化提取工艺简单、稳定、可行.     

正交试验法优选杜梨果实总黄酮的提取工艺

[目的]研究杜梨果实总黄酮最佳提取工艺条件.[方法]采用L9(34)正交试验法,以总黄酮得率为考察指标,研究提取温度、提取时间、提取次数及液料比对总黄酮得率的影响.[结果]影响杜梨果实总黄酮得率的主要因素为提取温度,其次是提取次数、提取时间和液料比.[结论]最佳提取工艺为60倍50 ;乙醇在80 ℃下水浴提取4次,每次3.5 h,在此条件下,黄酮提取率为0.377 5;.     

吴起野生沙棘不同部位总黄酮含量测定

对吴起野生沙棘不同部位的总黄酮含量进行了研究,发现沙棘果泥中总黄酮含量最高为814.03 mg/100g,其次为沙棘果皮、果油、果渣等,沙棘枝中含量最少为90.39 mg/100 g,这将为吴起野生沙棘总黄酮的进一步开发利用提供理论依据。     

不同水肥处理对枣果维生素C、黄酮和出干率的影响

[目的]本文通过研究不同水肥处理对红枣品质的影响,为合理科学的水肥管理提供理论基础。[方法]以延川木枣为供试材料,分析测定了在不同水肥处理条件下木枣果实中维生素C含量、黄酮含量以及出干率。[结果]结果表明：施氮和灌水在一定程度上可以显著提高枣果品质。其中,施氮量对枣果品质的影响较大。在施氮0.5 kg/株、灌水60 kg/株处理下,枣果中的维生素C含量最高,为492.3 mg/100g。在施氮0.5 kg/株,灌水20 kg/株处理下,枣果黄酮含量最高,为74.7 mg/100g。在施氮1.0 kg/株和灌水60 kg/株处理下,枣果出干率最高,为74.1%。[结论]从枣果的营养角度来看,本实验最佳施氮量为施氮0.5 ~1.0 kg/株,最佳灌水量为60 kg/株。总的来看,施氮和萌芽期灌水均能提高枣果维生素C和黄酮含量。     

甘薯叶中清除自由基活性物质的提取·保存与定性分析

探讨影响甘薯叶提取物清除不同种类自由基的提取工艺和保存温度,为其应用于抗衰老化妆品提供理论依据。     

Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves

[Objective] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [Method] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent,pH 8.0 of extracting liquid,storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves,just a correlation with scavenging rate against hydroxyl free radical shown in test. [Conclusion] The phenols in extracts could effectively scavenge both the DPPH free radical and hydroxyl free radical,whereas the flavones in extracts can only function on the hydroxyl free radical.     

Essential Oils and Antioxidants Derived From Citrus By-Products in Food Protection and Medicine: An Introduction and Review of Recent Literature

After a brief overview of the general production, market value, and uses of citrus by-products, this literature review will focus on the most highly refined “pharmaceutical grade” citrus oils and antioxidants that have been derived from peels or other fruit parts. Citrus oils have been used as a part of the perfume industry and in the practice of alternative medicine for a long time, but now there is a great deal of mainstream food processing and drug industry interest in them owing to the rediscovery or confirmation of some of their beneficial properties, as well their development for entirely new applications. Their roles as antimicrobial, immunomodulatory, and cancer chemopreventive or chemotherapeutic agents appear promising.