乌索酸的生产工艺

Production of ursolic acid, the anti-hepatitis effective composition from natural plant, Sambucus chinensis Lindl. was carried out and the scale-up preparation technology was studied. Extraction of the herb Sambucus chinensis Lindl. was extracted in reflux with 7 volume times of refluxing ethanol at 80℃ for 1 h for two times. The extract was purified with a seh-made specific impurity remover ＂YCXY-1＂ to yield ursolic acid of high purity. A new ＂Extraction/Gelation＂ technology for the production of ursolic acid was developed. The specific impurity remover ＂YCXY-1＂ showed high effectiveness in purification. The purity of the mass-produced ursolie acid was up to 99.8%. The chemical structure of the product was confirmed by the physicochemical constants and spectroscopic identification. The production of high-purity ursolic acid was optimized with natural plant as raw material and with only ethanol as extracting solvent. The difficulties such as isolation and impurity removal were addressed effectively. The novel technology is reasonable, convenient, practical, low-cost, high-yield, suitable for mass production.     

Protective effect of phytic acid hydrolysis products on iron-induced lipid peroxidation of liposomal membranes

Beneficial effects of dietary phytic acid (myo-inositol hexaphosphate; IP₆) have often been explained by its strong iron ion-chelating ability, which possibly suppresses iron ion-induced oxidative damage in the gastrointestinal tract. Because phytic acid is hydrolyzed during digestion, this work aimed to know whether its hydrolysis products (IP_2′ IP_3′, IP_4′ and IP₅) could still prevent iron ion-induced lipid peroxidation. Studies using liposomal membranes demonstrated that hydrolysis products containing three or more phosphate groups are able to inhibit iron ion-induced lipid peroxidation although their effectiveness decreased with dephosphorylation. Similarly, they also prevented iron ion-induced decomposition of phosphatidylcholine hydroperoxide. These results demonstrate that intermediate products of phytic acid hydrolysis still possess iron ion-chelating ability, and thus they can probably prevent iron ion-induced lipid peroxidation in biological systems.     

熊果酸衍生物的研究现状和展望

熊果酸(UA,3β-羟基-乌苏烷型-12-烯-28-羧酸),五环三萜化合物,作为药草的主要成分,存在于丰富的植物王国中.据报道,UA具有广谱的生物活性,调控和控制肿瘤细胞形成.UA多效件的抗肿瘤活性激发了专家们在这方面的积极研究,现综合国内外文献报道.对熊果酸结构修饰物及其药理活性进行综述.     

离子液体/盐双水相萃取分离锁阳中熊果酸

利用1-丁基-3-甲基咪唑氯([Bmim]Cl)和磷酸氢二钾(KH2PO4)双水相体系萃取分离锁阳中熊果酸,首先对[Bmim]Cl质量分数、KH2PO4质量分数、熊果酸粗提取液质量分数、NaCl质量分数、pH进行单因素研究,确定双水相体系组成为质量分数25%[Bmim]Cl-21%KH2PO4。然后,利用Box-Benhnken Design实验,对黄酮粗提取液质量分数、pH、NaCl质量分数进行了优化,结果表明:粗提液质量分数8.5%、NaCl质量分数1%、pH=4.7,熊果酸萃取率可达97.85%,与预测值98.3%接近。说明该优化工艺具有可行性。     

红枣中熊果酸的微波提取工艺研究

以红枣为原料,利用微波技术提取红枣中熊果酸。通过单因素实验和正交实验,考察φ(乙醇)、液料比、提取温度、微波功率、微波提取时间对熊果酸提取率的影响。结果表明,微波法提取红枣熊果酸的最佳工艺条件为:φ(乙醇)=90%、液料比20∶1(mL/g)、提取温度60℃、微波功率300 W、微波提取时间90 s。在此工艺条件下,熊果酸的提取率为2.412 7 mg/g。     

高效液相测定沙棘果皮中熊果酸和齐墩果酸的含量

建立沙棘果皮中齐墩果酸、熊果酸的含量测定方法。采用高效液相色谱法,Nova-Pack型C18柱,乙腈-甲醇-水-醋酸铵（65∶20∶15∶0.5）为流动相,检测波长为210nm;流速0.6mL/min。熊果酸回归方程为y=74.0x＋9.12,r=0.9995,线性范围0.11～10.64μg/mL,齐墩果酸回归方程为y=61.6x＋7.40,r=0.9992,线性范围0.12～12.36μg/mL。沙棘果皮中熊果酸和齐墩果酸的平均含量为1.187mg/g和0.352mg/g,平均回收率为100.3%、100.5%（n=3）,RSD分别为1.47%、1.50%（n=3）。该方法可同时测定沙棘果皮中齐墩果酸和熊果酸的含量,可用于药材质量控制。     

超声法提取山楂果中熊果酸和齐墩果酸的工艺研究

对超声法提取山楂果中熊果酸和齐墩果酸的工艺进行研究,利用L9(34)正交分析法考察各种因素的影响。结果表明,超声波提取山楂中熊果酸的最佳提取条件为:温度60℃,提取时间20 min,超声波功率180 W,溶剂乙醇体积浓度为80%;提取山楂中齐墩果酸的最佳提取条件为:温度60℃,提取时间20 min,超声波功率210 W,溶剂乙醇体积浓度为70%。     

离子液体中结晶分离熊果酸和齐墩果酸研究

为拓展结晶溶剂的范围和提高结晶分离熊果酸和齐墩果酸的性能,引入离子液体作为结晶溶剂。测定了熊果酸和齐墩果酸在六种离子液体+乙醇溶液中的溶解度数据,根据该数据,选取1-辛基-3-甲基咪唑六氟磷酸+乙醇混合溶液作为溶剂对熊果酸和齐墩果酸进行了结晶分离,并采用单因素实验对结晶工艺进行了初步优化。结果表明:在1-辛基-3-甲基咪唑六氟磷酸质量分数5%,熊果酸和齐墩果酸质量比1.5∶1,结晶温度30℃,结晶时间14 h的条件下,结晶产物中齐墩果酸的质量分数可以达到85%左右。     

高效液相色谱法测定化妆品中熊果酸的含量

采用甲醇超声提取,液相色谱分离的方法测定化妆品中熊果酸的含量。色谱条件为:Agilent HC-C18(250 mm×4.6 mm,5μm)色谱柱,流动相V(甲醇)∶V(水)∶V(冰乙酸)=87∶13∶0.03,流速1.0 mL/min,紫外检测波长215 nm。结果表明,在此条件下熊果酸在0.2μg/mL~103μg/mL与相应的峰面积具有良好的线性关系(r>0.999 7),线性回归方程为y=25.367 5x 0.546 9,回收率在96.4%~101.3%,方法精密度RSD<3.6%。     

氰尿酸合成工艺研究进展

从直接热解法、熔盐热解法、溶剂热解法三个方面对以尿素为原料热解制备氰尿酸的生产工艺和研究进展进行了综述,分析了各种工艺技术的优势与不足,提出了今后的研发重点和改进方向。重点介绍了氰尿酸生产工艺所取得的技术进步,对今后氰尿酸合成工艺的发展前景进行了展望。     

反相高效液相色谱法快速测定竹节参中齐墩果酸的含量

建立高效液相色谱快速测定竹节参中齐敦果酸含量的方法。选用Kromasil C18柱(150 mm×4.6 mm,5μm),乙腈-水(93∶7)为流动相,流速1.0 m L/min,检测波长215 nm。结果表明,齐墩果酸在2.36~23.60μg/m L浓度与峰面积有良好的线性关系(r=0.999 8),平均回收率98.86%,RSD 0.41%(n=6)。本法简单易行、重复性好、结果准确,可为竹节参中药材的质量评价提供依据。     

熊果酸香皂的制备及其生物活性研究

以棕榈油皂粒为皂基制备熊果酸香皂,按照国家标准方法对香皂中游离苛性碱、水分和挥发物含量进行检测,采用平板计数法和动物实验对该香皂的体外抑菌作用和安全性进行研究。结果表明,熊果酸香皂对白色假丝酵母、肺炎克雷伯氏菌、伤寒沙门氏菌、铜绿假单胞菌、MRSA1和MRSA2均具有明显抑菌作用,在熊果酸质量分数为7.5%时抑菌效果最为显著,动物实验表明香皂对小鼠皮肤和眼睛黏膜无不良反应和毒副作用,长期使用不会对皮肤产生刺激性。     

Extraction of ursolic acid from Ocimum sanctum leaves: Kinetics and modeling

Ursolic acid (UA) is a triterpene compound which shows significant biological potential. This study deals with the optimization and kinetics of UA extraction from Ocimum sanctum (OS) leaves in a stirred batch extraction. The influence of various extraction parameters on the extraction yield has been studied. The optimum extraction conditions were extraction time 40 min, speed of agitation 1000 rpm, temperature 323 K, solute to solvent ratio of 1:120. This resulted in 11.21 mg of UA/g of dried leaf powder of OS. The extraction kinetics behavior of UA from OS revealed that the extraction of UA followed a first order kinetics. The kinetic expression developed by Spiro and Siddique was used and the model is in good agreement with the experimental results. The diffusion coefficient determined ranged from 2 × 10^?11 to 6.10 × 10^?11 m²/s for the all set of experiments. The activation energy for the extraction of UA was found to be E_a = 10.45 kJ/mol.     

Carbonyl-carbonyl interactions stabilize the partially allowed Ramachandran conformations of asparagine and aspartic acid

Asparagine and aspartate are known to adopt conformations inthe left-handed -helical region and other partially allowedregions of the Ramachandran plot more readily than any othernon-glycyl amino acids. The reason for this preference has notbeen established. An examination of the local environments ofasparagine and aspartic acid in protein structures with a resolutionbetter than 1.5 Å revealed that their side-chain carbonylsare frequently within 4 Å of their own backbone carbonylor the backbone carbonyl of the previous residue. Calculationsusing protein structures with a resolution better than 1.8 Åreveal that this close contact occurs in more than 80% of cases.This carbonyl–carbonyl interaction offers an energeticsabilization for the partially allowed conformations of asparagineand aspartic acid with respect to all other non-glycyl aminoacids. The non-covalent attractive interactions between thedipoles of two carbonyls has recently been calculated to havean energy comparable to that of a hydrogen bond. The preponderanceof asparagine in the left-handed -helical region, and in generalof aspartic acid and asparagine in the partially allowed regionsof the Ramachandran plot, may be a consequence of this carbonyl–carbonylstacking interaction.     

Three phase partitioning coupled with ultrasound for the extraction of ursolic acid and oleanolic acid from Ocimum sanctum

In this study, three phase partitioning (TPP) is coupled with ultrasound for the extraction of ursolic acid (UA) and oleanolic acid (OA) from Ocimum sanctum leaves and process has been optimized to obtain maximum recovery. TPP is a relatively novel bioseparation technique used for the extraction, concentration and purification of enzymes and natural products. The technique of TPP was explored for the extraction of ursolic acid (UA) and oleanolic acid (OA) from O. sanctum leaves. The influence of various process parameters (pH, ammonium sulfate saturation, crude extract to t-butanol ratio, time and feed loading) on the extraction efficiency was investigated to get highest yield. The optimized conditions were found to be as follows: time – 120 min, pH – 7, ammonium sulfate saturation – 50% w/v, crude extract to t-butanol ratio – 1:1 and feed loading – 7.5% w/v. The highest yield obtained for UA and OA was 79.48% and 80.67% respectively under optimized conditions of TPP. Compared with TPP higher yield (83.36% and 85.58%) was obtained by ultrasound assisted TPP (UATPP) at 40 kHz and 180 W power and the time required was only 14 min as compared to 120 min of TPP. The extraction yield obtained was also compared with conventional solvent extraction and TPP-ultrasound was found to be an attractive technique for the extraction of UA and OA from O. sanctum leaves.     

Interactive transport of guanidinylated poly(propylene imine)-based dendrimers through liposomal and cellular membranes

The ability of guanidinylated poly(propylene imine) dendrimers to translocate across lipid bilayers was assessed by employing either a model phosphate-bearing liposomal membrane system or A549 human lung carcinoma cells. Two dendrimer generations, differing in the number of surface guanidinium groups, were employed, while surface acetylation or the use of spacers affected the binding of the guanidinium group to the phosphate moiety and finally the transport efficiency. Following adhesion of dendrimers with liposomes, fusion or transport occurred. Transport through the liposomal bilayer was observed at low guanidinium/phosphate molar ratios, and was enhanced when the bilayer was in the liquid-crystalline phase. For effective transport through the liposomal membrane, an optimum balance between the binding strength and the degree of hydrophobicity of the guanidinylated dendrimer is required. In experiments performed in vitro with cells, efficient penetration and internalization in subcellular organelles and cytosol was observed.     

以枸骨叶为原料提取熊果酸工艺的研究

采用正交实验筛选出从枸骨叶中提取熊果酸的最佳工艺。当使用 85%～ 95%乙醇提取两次、每次 80min时 ,对干枸骨叶的提取率达到 90 %。在后处理中使用 2 .5倍于沉淀物质量的石油醚洗涤 3次 ,最后使用乙醇重结晶得到产品。     

Ultrasonic assisted extraction of ursolic acid from apple pomace: A novel and facile technique

Substantial amount of apple pomace (AP) is produced in apple processing industries and is often discarded as waste which becomes a source of polluting the environment. However, the by-product constitutes a promising bioresource of ursolic acid with various biological activities. Therefore, this particular research study was aimed to develop a novel and facile method to separate ursolic acid from AP. First, AP was extracted with ultrasound assistance using methanol as extraction solvent, 2.86% with 10:1 (mL g^?1) of liquid–solid ratio, 300 W of ultrasonic power, 50°C of extraction temperature, and 90 min of ultrasonic time. Meanwhile, the disruption effect of ultrasound on AP was observed by scanning electron microscope. Second, a novel and facile method was applied to separation of ursolic acid, then a perfect colorless needle crystal of ursolic acid was obtained with the yield of about 1.34% of dry AP.     

Chain-breaking fused heterocyclic antioxidants: Antioxidant activities of 9H-xanthene-2,7-diols and α-tocopherol upon liposomal membranes

We evaluated the antioxidant activities of 9H-xanthene-2,7-diols and α-tocopherol (α-Toc) upon the oxidation of soybean phosphatidylcholine liposomal membranes, induced by 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) and 2,2′-azobis(2,4-dimethylvaleronitrile (AMVN). The stoichiometric factors of 9H-xanthene-2,7-diols, initiated with water-soluble AAPH and lipid-soluble AMVN, were 1.9–2.7 and 1.2–1.8-fold greater than those of α-Toc, respectively. The consumption profile of the antioxidant confirmed that 9H-xanthene-2,7-diol was completely consumed within the induction period (t _inh) and that the 9H-xanthene-2,7-diol oxidation product was formed. When all oxidation product was depleted, t _inh was terminated, and rapid oxidation occurred. These results suggested that the antioxidant activities of 9H-xanthene-2,7-diol depend not only on the initial hydrogen abstraction from 9H-xanthene-2,7-diol but also on a second hydrogen abstraction from the residual phenolic OH group of the oxidation product. Ascorbic acid (AsA) could not scavenge the radicals by itself in the lipid bilayer. However, when 9H-xanthene-2,7-diol was located in the lipid bilayer, the addition of AsA into the aqueous phase prolonged t _inh and reduced the rate of decay of 9H-xanthene-2,7-diol.     

酸性气体分离膜的研究现状及进展

当前,气体分离膜是一种环保绿色的分离技术,本文概括了目前用于去除CO2的商业膜材料(醋酸纤维素、聚酰亚胺和含氟聚合物),对不同膜的物理化学性质,气体渗透特性等进行了介绍。