The Physicochemical Characterization and In Vitro/In Vivo Evaluation of Natural Surfactants-based Emulsions as Vehicles for Diclofenac Diethylamine

ABSTRACT

Two sugar-based emulsifiers, cetearyl alcohol & cetearyl glycoside and sorbitan stearate & sucrose cocoate, known as potential promoters of lamellar liquid crystals/gel phases, were investigated in order to formulate an optimal vehicle for amphiphilic drug—diclofenac diethylamine (DDA).

Physico-chemical characterization and study of vehicle's physical stability were performed. Then, the in vitro DDA liberation profile, dependent on the mode of drug incorporation to the system, and the in vivo, short-term effects of chosen samples on skin parameters were examined.

Droplets size distribution and rheological behavior indicated satisfying physical stability of both types of vehicles. Unexpectedly, the manner of DDA incorporation to the system had no significant influence on DDA release. In vivo study pointed to emulsion's favorable potential for skin hydration and barrier improvement, particularly in cetearyl glycoside-based vehicle.     

Comparative Characterization of Total Flavonol Glycosides and Terpene Lactones at Different Ages, from Different Cultivation Sources and Genders of Ginkgo biloba Leaves

The extract from Ginkgo biloba leaves has become a very popular plant medicine and herbal supplement for its potential benefit in alleviating symptoms associated with peripheral vascular disease, dementia, asthma and tinnitus. Most research on G. biloba leaves focus on the leaves collected in July and August from four to seven year-old trees, however a large number of leaves from fruit cultivars (trees older than 10 years) are ignored and become obsolete after fruit harvest season (November). In this paper, we expand the tree age range (from one to 300 years) and first comparatively analyze the total flavonol glycosides and terpene lactones at different ages, from different cultivation sources and genders of G. biloba leaves collected in November by using the validated HPLC-ELSD and HPLC-PDA methods. The results show that the contents of total terpene lactones and flavonol glycosides in the leaves of young ginkgo trees are higher than those in old trees, and they are higher in male trees than in female trees. Geographical factors appear to have a significant influence on the contents as well. These results will provide a good basis for the comprehensive utilization of G. biloba leaves, especially the leaves from fruit cultivars.     

Microwave-Assisted Method for Simultaneous Extraction and Hydrolysis for Determination of Flavonol Glycosides in Ginkgo Foliage Using Brönsted Acidic Ionic-Liquid [HO(3)S(CH(2))(4)mim]HSO(4) Aqueous Solutions

The Brönsted acidic ionic-liquid [HO₃S(CH₂)₄mim] HSO₄, a novel dual catalyst–solvent, has been successfully applied in simultaneous microwave-assisted extraction and hydrolysis for the determination of flavonol glycosides in Ginkgo foliage. The parameters, namely the [HO₃S(CH₂)₄mim]HSO₄ concentration, microwave-irradiation power, microwave-irradiation time, and solid–liquid ratio, were optimized. The optimum conditions were: an amount of 1.5 M [HO₃S(CH₂)₄mim]HSO₄, a microwave-irradiation power of 120 W, an irradiation time of 15 min, and a solid–liquid ratio of 1:30 g/mL. Compared with traditional methods the proposed approach demonstrates higher efficiency in a shorter operating time, and is an efficient, rapid, and simple sample preparation method.     

直接苷化法合成十二烷基糖苷放大试验工艺过程的优化

在小试基础上,建立了一套反应釜体积为30 L直接苷化法合成十二烷基糖苷的实验室放大实验装置。考察了放大实验装置制备十二烷基葡萄糖苷的工艺参数的稳定性。结果表明,采用实验室小试工艺条件很难生产出与小试同等质量的烷基糖苷。指出了原料葡萄糖的含水量、醇糖摩尔比(简称醇糖比,下同)、葡萄糖在醇中的分散性及工艺参数的稳定性等因素影响了放大实验。最后确定优化的工艺条件为:原料葡萄糖选用无水的、且需过筛、脱水、预混合和分批投料;醇糖比为6∶1;温度、压力等工艺参数采用自动化控制;真空系统增设冷凝器和分离罐等。工艺过程优化后放大实验装置运行良好,所得产品经气相色谱仪分析与小试产品质量同等。     

甜菊糖苷的超声波提取及纯化工艺研究

研究了甜菊糖苷的超声波提取和纯化工艺.其中,甜菊糖苷的超声波提取的最佳工艺:在超声功率为200 W条件下,以水作为提取剂,料液比1∶8,提取温度80℃,提取时间60 min,甜菊糖苷的提取率为12.78％,较传统方法高10.27％.进而对提取液用醇沉法除杂,AB-8树脂富集,70％乙醇洗脱,活性氧化铝脱色,再经氧化铝柱层析深度脱色后,真空干燥得白色粉末,纯度为92.15％.该工艺具有用时短,提取率高,成本低,产品纯度高以及工艺绿色环保的优点.     

正交设计优选婆婆针中聚炔苷的提取工艺研究

目的探讨提取婆婆针中聚炔苷的工艺。方法以聚炔苷含量为指标,采用正交设计优选最佳提取工艺。结果最佳提取工艺为70%乙醇,10倍量,回流提取1 h,提取3次。结论乙醇提取法优于水提取法。乙醇浓度对婆婆针中聚炔苷溶出量影响显著。     

烷基糖苷聚氧丙烯醚的制备及性能

以碳链数为8/10、12/14的烷基糖苷(APG0810/APG1214)为原料,通过环氧丙烷(PO)改性得到一系列不同加合数的烷基糖苷聚氧丙烯醚.对样品的物理性能和应用性能进行测评,考察PO的引入对烷基糖苷理化性能的影响.结果表明:PO的引入在保持烷基糖苷优异乳化性能、润湿性能的同时大大降低了产品的泡沫性能,可以应用...     

糖苷对碱性溶液中钢筋表面钝化膜性能的影响

利用动电位极化和表面形貌观察技术,结合电容-电位曲线测量和Mott-Schottky分析,探讨了糖苷化合物对钢筋在含3.5%NaCl的Ca(OH)₂饱和溶液中的缓蚀行为和表面钝化膜性能的影响。结果表明,糖苷阻锈剂的加入可有效减缓钢筋的腐蚀,促进钢筋表面的钝化,提高钢筋耐Cl^-侵蚀能力;阻锈剂虽未改变钢筋表面钝化膜的半导体性能,但钝化膜内载流子密度却显著下降;钝化膜致密性分析表明,随糖苷浓度增大,钢筋表面钝化膜稳定性和致密性逐渐增强,耐蚀性提高。     

The C‐glycosyl flavonoid,aspalathin, is absorbed,methylated and glucuronidated intact in humans

Human bioavailability of the flavonoid dihydrochalcones is little understood, and no evidence exists for C‐glycosyl flavonoid absorption in humans. The present study uses catechol‐O‐methyltransferase to generate methylated metabolites of aspalathin (a C‐glycosyl dihydrochalcone from rooibos tea). One of the methylated forms, both with and without glucuronidation, was detected using LC‐MS/MS in the urine of human subjects (n = 6), demonstrating that deglycosylation is not a prerequisite for C‐glycosyl flavonoid absorption. Methylation is catalysed by both intestine and liver cytosolic extracts. The results show that flavonoid C‐glycosides are methylated and glucuronidated in vivo in an intact form in humans.