UHPLC–MS/MS determination and pharmacokinetic study of plantamajoside in rat plasma after oral administration of single plantamajoside and Plantago asiatica extract

A sensitive and reliable ultra‐high performance liquid chromatography coupled with tandem quadrupole mass spectrometry (UHPLC–MS/MS) method was developed for quantitation of plantamajoside in rat plasma. First, this study compared the pharmacokinetic properties of plantamajoside after oral administration of Plantago asiatica extract and pure plantamajoside in rat plasma with approximately the same dosage of 8.98 mg/kg. Second, chromatographic separation was performed on an Acquity HSS C₁₈ column (50 × 2.1 mm, p.d.1.7 μm) with isocratic elution using methanol–water (80:20, v /v) as mobile phase at a flow rate of 0.25 mL/min. The calibration curves were linear over the range of 0.1–100 ng/mL for plantamajoside. At different time points (0, 0.083, 0.167, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6 and 8 h) after administration, the concentrations of plantamajoside in plasma were measured and the main pharmacokinetic parameters were estimated. The study indicates that the pharmacokinetics of plantamajoside in rat plasma have significant differences between two groups.     

LC–MS/MS method for simultaneous determination of flavonoids and physalins in rat plasma: Application to pharmacokinetic study after oral administration of Physalis alkekengi var. franchetii (Chinese lantern) extract

A rapid and sensitive liquid chromatography with tandem mass spectrometry (LC‐MS/MS) method was developed and validated for the simultaneous determination of luteolin, luteolin‐7‐O ‐β ‐D‐glucopyranoside, physalin A, physalin D and physalin L in rat plasma. Scutellarein and dexamethasone were used as the internal standards (IS). Plasma samples were prepared by liquid‐liquid extraction with ethyl acetate. The five constituents were separated on an Acquity UPLC BEH C₁₈ column (100 mm × 2.1 mm, 1.7 μm). A gradient elution procedure was used with acetonitrile (A)‐0.1% aqueous formic acid (B). Mass spectrometric detection was performed in negative ion multiple reaction monitoring mode with an electrospray ionization (ESI) source. This method showed good linearity (r ² > 0.997) over a concentration range of 2.0–500 ng/mL with a lower limit of quantification of 2.0 ng/mL for all five compounds. The inter‐ and intra‐day accuracy ranged from 91.7 to 104%, and precisions (RSD) were <6.46% for all analytes. The extraction recoveries of all analytes were >85%. This validated method was successfully applied for the first time to the pharmacokinetic study of five ingredients after oral administration of 70% ethanol extract of Chinese lantern in rats.     

Study of the effect of Wuzhi tablet (Schisandra sphenanthera extract) on tacrolimus tissue distribution in rat by liquid chromatography tandem mass spectrometry method

A liquid chromatography/tandem mass spectrometry (LC‐MS/MS) method was developed and validated for determining tacrolimus (FK506) in rat tissues to study the effect of Schisandra sphenanthera extract on FK506 tissue distribution. After a liquid–liquid extraction with ethyl acetate, FK506 and ascomycin (IS) were subjected to LC‐MS/MS analysis using positive electrospray ionization under multiple reactions monitoring mode. Chromatographic separation of FK506 and ascomycin was achieved on a Hypersil BDS C₁₈ column with a mobile phase consisting of methanol‐water (containing 2 mM ammonium acetate, 95 : 5, v/v). The intra‐ and inter‐batch precision of the method were less than 8.8 and 9.8%, respectively. The intra‐ and inter‐batch accuracies ranged from 97.5 to 104.0%. The lowest limit of quantification for FK506 was 0.5 ng/mL. The method was applied to a FK506 tissue distribution study with or without a dose of Wuzhi (WZ) tablet. Most of the FK506 tissue concentrations were slightly increased after a concomitant WZ tablet dose, but the whole blood concentration of FK506 was dramatically increased 3‐fold after a concomitant WZ tablet dose. These results indicated that the LC‐MS/MS method was rapid and sensitive enough to quantify FK506 in different rat tissues, and strict drug monitoring is recommended when co‐administering WZ tablet in clinical use. Copyright © 2009 John Wiley & Sons, Ltd.     

人参中锗的分光光度法测定

采用灰化法分解人参样品，用分光光度法测定人参中的有机锗含量，方法简便，快捷，回收率为98．90％－99．78％。     

一种通过改进Canny算子提取光弹条纹骨架线的方法

光弹性法是确定应力集中系数的有效手段，在实际工程中应力参数都是通过分析光弹干涉条纹图获得的，由于光弹干涉条纹图的复杂性，且影响成像质量的因素较多，因此如何从光弹干涉条纹图中撇开其复杂性，较高精度的提取骨架线，是一项较困难的工作，本文提出一种由改进的Canny算子对条纹方位图进行直接运算提取光弹条纹骨架线的算法，实验表明此方法对光弹条纹图很有效。     

Chemical composition and antibacterial activity of methanolic extract and essential oil of Iranian Teucrium polium against some of phytobacteria

The antibacterial activity of essential oil and methanolic extract of Teucrium polium was determined against Pseudomonas aeruginosa, Pantoea agglomerans, Brenneria nigrifluens, Rhizobium radiobacter, Rhizobium vitis, Streptomyces scabies, Ralstonia solanacearum, Xanthomonas campestris and Pectobacterium cartovorum by disc diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration were determined by using the serial dilution method. Chemical composition of essential oil and methanolic extract was determined by GC-MS and HPLC. α-Pinene (25.769%) and myrcene (12.507) were of the highest percentage in T. polium essential oil, and sinapic acid (15.553 mg/g) and eugenol (6.805 mg/g) were the major compounds in the methanolic extract. Our results indicate that both methanolic extract and essential oil did not show antibacterial activity against P. aeruginosa. Also the essential oil did not show antibacterial activity against P. cartovorum. In general, both methanolic extract and essential oil showed the same antibacterial activity against R. solanacearum, P. agglomerans, B. nigrifluens and S. scabies.     

Effect of a topical formulation containing Calophyllum brasiliense Camb. extract on cutaneous wound healing in rats

This study evaluated the wound healing effects of topical application of an emulsion containing the HPLC-standardised extract from Calophyllum brasiliense Cambess (Clusiaceae) leaves in rats. The macroscopic analysis demonstrated that the wounds treated with the C. brasiliense emulsion healed earlier than the wounds treated with emulsion base and Dersani®. The percentage of wound healing in the group treated with the C. brasiliense emulsion was significantly higher than in the other groups at 7 and 14 days. On day 14, the animals treated with the C. brasiliense emulsion exhibited a 90.67% reduction of the wound areas. The histological evaluation revealed that on day 21, the group treated with the C. brasiliense emulsion exhibited a significant increase in fibroblasts compared with the other groups. Thus, the C. brasiliense emulsion had healing properties in the topical treatment of wounds and accelerated the healing process.     

Simultaneous quantification of 10 saponins in Chinese Shizhu Panax by UPLC-ESI-MS

A simple and rapid method was established and validated for the simultaneous quantification of 10 saponins, namely ginsenosides-Rb₁, Rb₂, Rb₃, Rc, Rd, Rg₁, Rg₂, Re, Rf and Notoginsenside R₁, in Chinese Shizhu Panax by ultra performance liquid chromatography coupled with an electrospray mass spectrometry (UPLC-ESI-MS). In addition, the contents of the analytes in different parts of Chinese Shizhu Panax were also analysed. The results showed that the concentration of saponins had a reference to the different parts of Chinese Shizhu Panax. The established method could be used as a new analytical approach for assessment of the quantity of Chinese Shizhu Panax.     

Inhibition of thermal induced protein denaturation of extract/fractions of Withania somnifera and isolated withanolides

This study describes the in vitro inhibition of protein denaturation of extract/fractions of Withania somnifera and isolated withanolides including 20β hydroxy-1-oxo(22R)-witha-2,5,24 trienolide (1), (20R,22R-14α,20α)-dihydroxy-1-oxowitha-2,5,16,24 tetraenolide (2). The results showed that the extract/fractions of the plant evoked profound inhibitory effect on thermal-induced protein denaturation. The chloroform fraction caused the most dominant attenuation of 68% at 500 μg/mL. The bioactivity-guided isolation from chloroform fraction led to the isolation of compounds 1 and 2 that showed profound protein inhibition with 78.05% and 80.43% effect at 500 μg/mL and thus strongly complimented the activity of extract/fractions. In conclusion, extract/fractions of W. somnifera possessed strong inhibition of protein denaturation that can be attributed to these isolated withanolides.     

Characterization of odorous contaminants in post‐consumer plastic packaging waste using multidimensional gas chromatographic separation coupled with olfactometric resolution

The increasing world population with their growing consumption of goods escalates the issue of sustainability concepts with increasing demands in recycling technologies. Recovery of post‐consumer packaging waste is a major topic in this respect. However, contamination with odorous constituents currently curtails the production of recycling products that meet the high expectations of both consumers and industry. To guarantee odor‐free recyclates, the main prerequisite is to characterize the molecular composition of the causative odorants in post‐consumer plastic packaging waste. However, targeted characterization of odorous trace contaminants among an abundance of volatiles is a major challenge and requires specialized and high‐resolution analytical approaches. For this aim, post‐consumer packaging waste was characterized by sensory analysis and two‐dimensional high resolution gas chromatography coupled with mass spectrometry and olfactometry. The 33 identified odorants represent various structural classes as well as a great diversity of smell impressions with some of the compounds being identified in plastics for the first time. Substances unraveled within this study provide insights into sources of odorous contamination that will require specific attention in the future in terms of screening and prevention in recycling products.