GC法测定止痒消炎水中麝香草酚的含量

目的建立麝香草酚含量的气相色谱测定法。方法色谱条件为DB-I石英毛细管色谱柱,程序升温,起始温度80℃,保持4 m in,以15℃.m in-1的速率升至120℃,保持6 m in,FID检测器,内标物为水杨酸甲酯。结果麝香草酚在0.1506~0.3514g.L-1的浓度范围内线性关系良好(r=0.9991),加样平均回收率为98.34%,RSD=1.77%(n=6)。结论该方法处理简单、分离效果好,结果准确可靠。     

Thymol analogues with antioxidant and L‐type calcium current inhibitory activity

Thymol is a natural product, which has antioxidant activity. 4‐Morpholinomethyl‐2‐isopropyl‐5‐methylphenol (THMO), and 4‐Pyrrolidinomethyl‐2‐isopropyl‐ 5‐methylphenol (THPY) were synthesized by reacting thymol with formaldehyde and, respectively, morpholine or pyrrolidine. Since there is a relationship between the antioxidative status and incidence of human disease, anti‐superoxidation, free radical scavenger activity, and anti‐lipid peroxidation of the thymol analogues were determined by xanthine oxidase inhibition, cytochrome C system with superoxide anion releasing with formyl‐Met‐Leu‐Phe (fMLP)/cytochalasin (CB) or phorbol myristate acetate (PMA) activating pathway in human neutrophils. All compounds studied had antioxidant activity. Mannich bases derived from thymol were generally found to be more potent compounds than thymol. THMO demonstrated the greatest antioxidant activity with IC₅₀ values for xanthine oxidase inhibition and anti‐lipid peroxidation being 21±2.78 and 61.29±5.83 µM, respectively. Moreover, since oxidative stress by free radical regulates the activity of L‐type Ca²⁺ channel, the whole‐cell configuration of the patch‐clamp technique was used to investigate the effect of THMO upon ionic currents within NG108‐15 cells. THMO (10 µM) suppressed the peak amplitude of L‐type Ca²⁺ inward current (I_Ca,L), indicating that the antioxidative potential of the thymol analogues might be related to calcium current inhibition. The present studies suggest that THMO‐dependent antioxidant and calcium ion current inhibition activity may be useful in treating free radical‐related disorders. Drug Dev Res 64:195–202, 2005. © 2005 Wiley‐Liss, Inc.     

麝香草脑霜剂的二阶导数分光光度测定

采用二阶导数分光光度法测定百里香霜中麝香草脑的含量，可消除基质的干扰。平均回收率为９９．２９％，ＲＳＤ为０．３５％。方法简便、准确。     

香朴感冒软胶囊质量标准研究

目的:建立香朴感冒软胶囊(香薷、厚朴、黄芩)的质量标准。方法:采用薄层色谱法鉴别香朴感冒软胶囊中香薷、厚朴及黄芩;用高效液相色谱法同时对制剂中百里香酚、厚朴酚、和厚朴酚进行定量分析。结果:定性鉴别分离度好,专属性强;百里香酚的含量测定线性范围为0.32~3.2μg(r=0.9998,n=6),平均回收率为99.44(RSD=1.3,n=6);和厚朴酚的含量测定线性范围为0.20~2.0μg(r=0.9997,n=6),平均回收率为99.78(RSD=1.58,n=6);厚朴酚的含量测定线性范围为0.49~4.89μg(r=0.9998,n=6),平均回收率为99.41(RSD=0.51,n=6);结论:所建立之方法可靠、准确、专属性强,可有效控制香朴感冒软胶囊的质量。     

Thymol and related alkyl phenols activate the hTRPA1 channel

BACKGROUND AND PURPOSE: Thymol, a major component of thyme and oregano, has medical uses in oral care products as an astringent and antibiotic. Its distinctive sharp odour and pungent flavour are considered aversive properties. The molecular basis of these aversive properties is not well understood. EXPERIMENTAL APPROACH: The ability of thymol to activate human transient receptor potential channel A1 (hTRPA1) expressed in stably transfected human embryonic kidney 293 (HEK293) cells was measured by membrane potential and calcium-sensitive dyes in a fluorescence-imaging plate reader (FLIPR) assay. Direct activation of hTRPA1 currents was measured by whole-cell voltage clamp recording. Intracellular calcium changes were measured using fura-2 dye. The FLIPR assay was also used to measure membrane potential changes elicited by thymol after pretreatment with camphor, a known TRPA1 inhibitor. The ability of related alkyl phenols to activate hTRPA1 was also determined. KEY RESULTS: Thymol potently activated a membrane potential response and intracellular calcium increase in hTRPA1-expressing HEK293 cells in a concentration-dependent manner. Activation by thymol desensitized hTRPA1 to further exposure to thymol or the known ligand allyl isothiocyanate (AITC). The related phenols 2-tert-butyl-5-methylphenol, 2,6-diisopropylphenol (propofol) and carvacrol also activated hTRPA1. Phenols with less bulky carbon substitutions and lower logP values were less potent in general. The response to thymol was blocked by camphor.CONCLUSIONS AND IMPLICATIONS: These results suggest a role for hTRPA1 activation in the reported pungent and aversive properties of some of these pharmaceutically important phenols.     

Thymol,thyme, and other plant sources: Health and potential uses

Thymol is a naturally occurring phenol monoterpene derivative of cymene and isomer of carvacrol. Thymol (10–64%) is one of the major constituent of essential oils of thyme (Thymus vulgaris L., Lamiaceae), a medicinal plant with several therapeutic properties. This plant, native to Mediterranean regions, is commonly used as a culinary herb and also with a long history of use for different medicinal purposes. Nowadays, thymol and thyme present a wide range of functional possibilities in pharmacy, food, and cosmetic industry. The interest in the formulation of pharmaceuticals, nutraceuticals, and cosmeceuticals based on thymol is due to several studies that have evaluated the potential therapeutic uses of this compound for the treatment of disorders affecting the respiratory, nervous, and cardiovascular systems. Moreover, this compound also exhibits antimicrobial, antioxidant, anticarcinogenesis, anti‐inflammatory, and antispasmodic activities, as well as a potential as a growth enhancer and immunomodulator. In the present review, these bioactivities have been covered because some of them can contribute to explain the ethnopharmacology of thymol and its main source, T. vulgaris. Other important aspects about thymol are discussed: its toxicity and bioavailability, metabolism, and distribution in animals and humans.