Use of headspace mulberry paper bag micro solid phase extraction for characterization of volatile aromas of essential oils from Bulgarian rose and Provence lavender

In this study, a new sampling method called headspace mulberry paper bag micro solid phase extraction (HS-MPB-μ-SPE) combined to gas chromatography-mass spectrometry has been applied for the analysis of volatile aromas of liquid essential oils from Bulgarian rose and Provence lavender. The technique uses an adsorbent (Tenax TA) contained in a mulberry paper bag, minimal amount of organic solvent. Linearities for the six-points calibration curves were excellent. LOD values were in the rage from 0.38 ng mL⁻¹ to 0.77 ng mL⁻¹. Overall, precision and recovery were generally good. Phenethyl alcohol and citronellol were the main components in the essential oil from Bulgarian rose. Linalyl acetate and linalool were the most abundant components in the essential oils from true lavender or lavandin. Additionally, the relative extraction efficiencies of proposed method have been compared with HS-SPME. The overall extraction efficiency was evaluated by the relative concentration factors (CF) of the several characteristic components. CF values by HS-MPB-μ-SPE were lower than those by headspace solid phase microextraction (HS-SPME). The HS-MPB-μ-SPE method is very simple to use, inexpensive, rapid, requires small sample amounts and solvent consumption. In addition, this method allowed combining of extraction, enrichment, and clean-up in a single step. HS-MPB-μ-SPE and GC/MS is a promising technique for the characterization of volatile aroma compounds from liquid essential oils.     

Sensitive distinction between herbs by terahertz spectroscopy and a metamaterial resonator

Terahertz spectroscopy, combined with a metamaterial resonator, was used to distinguish varieties of herbs that look alike to the naked eye. The metamaterial resonator, based on an ohm-ring, was experimentally demonstrated to exhibit two significant resonant peaks in the range from 0.2 to 1.4?THz. The resonant peaks were shifted to lower frequency with changes of the surface permittivity, and this feature was applied to identify varieties of herbs. In the experiment, different borneols were effectively identified according to the different degree of redshift. This work demonstrates that metamaterial resonator is a sensitive tool for terahertz spectral sensing, and shows a new detection method for different herbs.     

Three New Abietane‐type Diterpenes from the Bark of Cryptomeria japonica

Three new abietane‐type diterpenoids, 7β‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐6α,11‐diol ( 1 ), 7α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐6α,11‐diol ( 2 ), and 6α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐7α,11‐diol ( 3 ), as well as two known abietane‐type diterpenoids, 12‐methoxyabieta‐8,11,13‐triene‐6α,7β,11‐triol ( 4 ) and 6α‐acetoxy‐12‐methoxyabieta‐8,11,13‐triene‐7β,11‐diol ( 5 ), were isolated from the MeOH extract of the bark of Cryptomeria japonica. Their structures were determined by analysis of spectroscopic data and comparison of NMR data with those of related metabolites.     

Simultaneous determination of total arsenic and total selenium in Chinese medicinal herbs by hydride generation atomic fluorescence spectrometry in tartaric acid medium

By HG-AFS, a new method was proposed for simultaneous determination of total arsenic and total selenium existed in the Chinese medicinal herbs in tartaric acid medium. The effects of analytical conditions and coexisting ions on the fluorescence signal intensity of analytes were investigated. The proposed method was provided with linear response ranges above 22 μg l⁻¹ for As and 44 μg l⁻¹ for Se, and the detection limits of 0.13 and 0.12 μg l⁻¹ were obtained for As and Se respectively. The recoveries of 93.8–96.1% for As and 95.3–99.1% for Se, and the precision of 1.2–3.8% and 2.4–5.3% (R.S.D., n = 8) respectively, were obtained via simultaneous determined four samples of Chinese medicinal herbs and three certified botanic reference materials successfully. The proposed method has the advantages of simple operation, high sensitivity and high efficiency.     

Recent advances on herb‐derived constituents‐incorporated wound‐dressing materials: A review

Since ancient times, wound dressings have evolved with persistent and substantial changes. Several efforts have been made toward the development of new dressing materials, which can meet the demanding conditions for the treatment of skin wounds. Currently, many studies have been focused on the production and designing of herb‐incorporated wound dressings. Herb‐derived constituents are more effective than conventional medicines because of their nontoxic nature and can be administered over long periods. Herbal medicines in wound healing provide a suitable environment for aiding the natural course of healing. This review mainly focuses on the diverse approaches that have been developed to produce a wound dressing material, which can deliver herb‐derived bioactive constituents in a controlled manner. This review also discusses the common wound‐dressing materials available, basic principles of wound healing, and wound‐healing agents from medicinal plants.     

五种抗HIV活性中草药微量元素的主成分分析

对产自云南的5种抗HIV活性中草药:臭灵丹、紫茎泽兰、辣子草、滇石栎、密蒙花进行了微量元素测定和主成分分析.结果显示,微量元素分为3个主分量,综合评价第一位的是臭灵丹.     

导数-原子捕集-火焰原子吸收光谱法测定中草药中的微量铜

研究了在原有基础上对原子捕集装置的改进，并与导数原子吸收光谱法结合，使铜的测定灵敏度有较大提高。在10mV/min灵敏度档下，捕集时间为2min时，方法的检出限和特征浓度分别为0.52和0.85μg/L，分别较常规火焰原子吸收法改善1和2个数量级。利用该法成功测定了甘草、柴胡等10味中药中的微量铜，平均回收率为94.2%－104％。     

SPE isolation of low‐molecular oxygen compounds from essential oils

Analytical procedures of complex mixtures frequently involve their initial pre‐fractionation to make the analysis easier or possible. Recently, SPE is frequently applied for this purpose. This article discusses the possibility of essential oil's fractionation using SPE with octadecyl modified silica. The presented results show that developed SPE with C‐18 sorbent allows for easy and total isolation (100% recovery) of low‐molecular oxygen compounds from the remaining compounds, for which the recovery exceeds 95%. The obtained recoveries are satisfactory for preliminary separation of essential oils for analytical and preparative purposes.     

ICP-OES和ICP-MS法研究中草药中元素的溶出特性

中药中微量元素的含量,尤其是有毒重金属的含量日益引起人们的重视[1].测定中草药原生药金属元素含量的报道较多[2-7],而系统研究煎煮前后微量元素分布的报道较少[8-12].本文选取了常用配方中最常用的十八种中草药,采用电感耦合等离子体原子发射光谱法(ICP-OES)和电感耦合等离子体质谱法(ICP-MS)对其中的Al、Ca、Fe、K、Mg、Mn、Na、Sr、Zn、V、Ni、Cu、Cd和Pb等14种金属元素煎煮溶出的情况进行了初步研究,试图为中药研究提供一些基础数据.     

六种常用滋补中药铅、汞、镉含量的测定

为了解山楂、山药、百合、枸杞子、麦冬、莲子六种常用滋补中药有害重金属含量,用石墨炉原子分光光度法测定了六种中药的铅和镉含量,用冷原子吸收分光光度法测定了六种中药的汞含量。结果表明,六种中药有害重金属含量由高到低顺序为:铅、镉、汞,六种中药汞含量均不超过0.02 mg/kg,镉含量最高0.32 mg/kg,最低0.08 mg/kg,铅含量在0.53~2.43 mg/kg之间。