离子液体在天然活性物质提取中的应用研究进展

查阅近年来国内外相关文献,并进行分析、归纳和总结 , 综述离子液体在天然活性物质提取中的应用研究进展。离子液体作为一 种绿色溶剂,并以其独特性质,近年来在天然活性物质提取领域的应用研究备受关注。不过,目前用于天然活性物质提取的离子液体大 多仅为咪唑类型, 且尚未发现不同类型离子液体对不同种类天然活性成分的提取效率具有明显的特异性和规律性, 这有待进一步深入研究。     

香菇多糖微波辅助提取及体外免疫学活性研究

利用微波辅助水浸提法优化影响香菇多糖提取的单因子试验(料液比、浸提温度、浸提时间、微波处理时间等)和多因子的正交试验[L9(34)]。结果表明,香菇多糖的最佳提取条件为:料液比1∶30,浸提温度90℃,浸提时间2h,微波处理3m in。在此条件下,香菇多糖提取率为4.75%。香菇多糖粗品的体外免疫学研究的结果表明,在25~1600μg/mL的浓度范围内,多糖都具有促进小鼠脾淋巴细胞体外增殖的作用;在25~400μg/mL的浓度范围内,多糖对脾淋巴细胞增殖活性呈现一定的剂量依赖性。     

龙眼壳黄酮的微波提取及体外抗氧化活性研究

研究了微波辅助提取龙眼壳黄酮的工艺条件,并对其进行了抗氧化性能的研究。正交试验结果表明较佳提取工艺为:V(70%乙醇)∶m(龙眼壳粉)=30 m L∶1 g,微波功率480 W处理20 s后,于水浴30℃浸提30min,龙眼壳黄酮得率为3.465%。抗氧化试验表明龙眼壳黄酮对亚硝酸盐具有良好的清除能力,其效果优于Vc,对卵黄脂蛋白脂质过氧化及羟基自由基具有明显的抑制作用,其效果分别弱于对照物2,6-二叔丁基-4-甲基苯酚(BHT)和Vc。     

微量元素在寻找新活性物质中的应用研究

通过对31种中草药的微量元素分析,应用现代生物学和现代医学的观点讨论了微量元素的种类、含量以及不同微量元素谱在生理生化、药理药效上的相关性,提出应用微量元素测定方法寻找新的活性物质和中草药深层开发的可能性。     

虎耳草中抗氧化活性物质的提取及成分研究

对虎耳草中抗氧化活性物质提取工艺进行优化研究并对其进行总黄酮、总多酚、多糖的含量测定。通过单因素试验和Box-Behnken设计,以虎耳草中抗氧化活性物质对DPPH.自由基的清除率为响应值,利用响应面分析法对提取参数进行优化。结果表明:在提取温度39℃、料液比1∶40.5(g/mL)、提取时间3.7 min,微波功率500 W的优化条件下,以水为提取溶剂时,其提取液对DPPH.的清除率达到最大,为80.32%,同时将该提取液进行成分分析,1 g提取液中含有总黄酮11.30 mg,总多酚20.27 mg,多糖55.85 mg。     

火龙果果皮红色素的微波提取工艺及其应用

以火龙果果皮干粉为原料,就微波提取火龙果果皮红色素的工艺进行研究。结果表明,果皮红色素的最大吸收峰波长是535 nm,溶液呈鲜红色;微波提取火龙果果皮红色素的最优条件为:以50%乙醇为浸提剂,微波功率为180 W,提取时间为60 s,最佳料液比为1∶60 g/mL。微波提取火龙果色素的效果明显优于常规的溶剂浸提法。当火龙果果皮红色素粗提物含量在40 mg/100 g果冻时,果冻的感官评分最高。当色素含量为23 mg/100 mL时,制作出来的调和酒与购买的调和酒颜色接近,呈粉色。应用在果冻及调和酒里的火龙果果皮红色素都在无避光室温放置一个月后颜色消失。维生素C对于火龙果果皮红色素有防降解作用。该色素应低温避光保存。     

龙眼壳黄酮的微波提取及体外抗氧化活性研究北大核心CSCD

研究了微波辅助提取龙眼壳黄酮的工艺条件,并对其进行了抗氧化性能的研究。正交试验结果表明较佳提取工艺为:V(70%乙醇)∶m(龙眼壳粉)=30 m L∶1 g,微波功率480 W处理20 s后,于水浴30℃浸提30min,龙眼壳黄酮得率为3.465%。抗氧化试验表明龙眼壳黄酮对亚硝酸盐具有良好的清除能力,其效果优于Vc,对卵黄脂蛋白脂质过氧化及羟基自由基具有明显的抑制作用,其效果分别弱于对照物2,6-二叔丁基-4-甲基苯酚(BHT)和Vc。     

两种水溶性抗菌活性物质的分离提取

对水溶性、不解离的极性物质分离时,一般采用吸附层析和凝胶层析等途径。实验通过硅胶柱层析、葡聚糖凝胶柱层析以及硅胶ＧＦ２５４制备型薄板层析,从发酵液样品中分离出两种有抗菌活性的纯物质。薄层层析的展开剂为二氯甲烷－四氢呋喃－甲醇－水（２５：３０：２）,分离出的组分中Ｒｆ＝０．７和Ｒｆ＝０．８两种物质有抗菌活性。硅胶柱层析洗脱过程为梯度洗脱,先用１５０ｍｌ上述展开剂洗脱,再用二氯甲烷－甲醇（２０：８０）     

Antimicrobially active substances

The antimycotic activity of 41 quaternary ammonium compounds was studied. The spectrum of their effect was evaluated in eight microbial strains. Homologues, isomers or close analogues of Septonex, i.e. α-carbetoxypentadecyl-trimethylammonium bromide (XII) were found to be the most active. The presence of an alicyclic or an aromatic ring or of a pyridine residue inhibited antimycotic activity, while substitution of hydrogen by a halogen potentiated it.     

Antibacterially active substances

Synthesis of two hydroxy-derivatives of nalidixic acid as a result of microbial transformation was demonstrated in certain species of the genusAspergillus. Aspergillus alliaceus produced 7-hydroxy-nalidixic acid andAspergillus niger 6-hydroxy-nalidixic acid. It was demonstrated that the antibacterial activity of both hydroxy-derivatives (tested inEscherichia coli) was lower than that of the initial nalidixis acid.     

Alternative sources of biologically active substances

The majority of antibiotics and substances with diverse biological activity used in medicine are produced by actinomycetes, nonfilamentous bacteria and fungi. Other microorganisms, such as myxobacteria, pseudomonads, nocardias, basidiomycetes, marine microorganisms, enterobacteria, halobacteria, hyperthermophiles etc. are investigated for new biologically active metabolites.     

Placenta--a source of biologically active substances

In the review there are some data displaying the scientific and patent literature presenting placenta as a rich source of some biologically active substances (BAS): proteins, lipids, enzymes, glycolipids and glycolipoproteins, hormones. This information is capable to be used while developing the techniques of BAS producing from placenta in order of creating the organospecific complex preparations with medically-preventive properties.     

Receptor-based assays in screening for biologically active substances.

Molecular biology has identified new receptors and ligands which are deregulated in diseases such as cancer and autoimmune conditions and which provide rational targets for therapeutic intervention. Advances in instrumentation and methodology make it possible to screen large numbers of samples in simple receptor-ligand binding assays in the search for drug candidates. Caution must be exercised in the interpretation of data derived from such assays. This is particularly pertinent to the recently characterized receptors, such as the cytokine receptors, as we do not fully understand the relationship between the receptor type and the linkage of receptors to the appropriate or inappropriate second messenger systems that are used in the experimental screening protocols and the disease state.