SPME-GC-MS analysis of commercial henna samples (Lawsonia inermis L.)

The aim of this work was to provide a characterisation of volatile constituents from different commercial batches of henna (Lawsonia inermis) leaves of different geographic origin. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used for the purpose. A total of 72 components were identified by GC–MS in the headspace of different henna samples which proved to differ considerably from each other, because they were characterised by different classes of components, mainly aliphatic compounds (9.0–64.7%), terpenoids (5.8–45.5%) and aromatics (7.9–45.2%), with alkanes (0.9–18.5%), aldehydes (2.1–18.8%) and carboxylic acids (3.1–29.3%), monoterpenes (3.4–30.0%) and sesquiterpenes (0.8–23.7%) and phenyl propanoids (0.6–43.1%), being the most abundant, respectively. Major representatives of these groups were n-hexadecane (0.5–4.7%), (2E)-hexenal (0.5–11.7%) and acetic acid (2.8–24.5%), limonene (0.8–14.7%), carvol (3.8–7.1%), geranyl acetone (1.4–7.9%) and (E)-caryophyllene (3.3–8.4%), and (E)-anethole (0.6–35.0%), respectively. We assume that factors such as the manufacturing process, the storage conditions and the different geographic origin of the samples may contribute to such variability.     

High‐performance liquid chromatographic method for the quantification of Mitragyna inermis alkaloids in order to perform pharmacokinetic studies

In Africa, Mitragyna inermis (Willd.) O. Kuntze (Rubiaceae) is commonly used in traditional medicine to treat malaria. Antimalarial activity is mostly due to the hydromethanolic extract of M. inermis leaves and especially to the main alkaloids, uncarine D and isorhynchophilline. In the present study, we describe for the first time an HPLC method for the simultaneous quantification of uncarine D and isorhynchophylline in biological matrices. SPE was used to extract the components and the internal standard naphthalene from human and pig plasma samples. Chromatographic separation was performed on a C‐18 reversed column at a flow rate of 1 mL/min, using methanol–phosphate buffer (10:90, pH 7), as a mobile phase. Good linearity was observed over the concentration ranges of 0.0662–3.31 μg/mL for uncarine D and 0.0476–2.38 μg/mL for isorynchophylline. The precision was less than 12% and the accuracy was from 86 to 107% without any discrepancy between the two species. Uncarine D and isorhynchophylline recoveries were over 80%. These results allowed the quantification of both uncarine D and isorhynchophylline in pig plasma after intravenous administration of M. inermis extract.     

Four- and Eight-Carbon Homologation of Benzaldehyde by (1Z,3Z)-Butyltelluro-1,3-Butadiene: Synthesis of Navenone B: Alarm Pheromone of the Mollusk Navanax inermis

Four- and eight-carbon homologation of benzaldehydes is described. The hydrotelluration of (Z)-1-methoxy-but-1-en-3-ynes 1 afforded (1Z,3Z)-1-butyltelluro-4-methoxy-1,3-butadiene 2, this compound 2 underwent a Te/Li exchange reaction, and the butadienyllithium 3 obtained reacted with benzaldehyde to form the corresponding allylic alcohol 4 with total retention of configuration. The allylic alcohol 4a formed underwent acidic hydrolysis, resulting in 5-phenyl-(2E,4E)-dienal 5 (four-carbon homologation of benzaldehyde). Product 5 reacted with the butadienyllithium 3, affording the alcohol 9-phenyl-(1Z,3Z,6E,8E)-1-methoxy-5-hydroxy-nonatetraene 6, which was hydrolyzed or spontaneously transformed into 9-phenyl-(2E,4E,6E,8E)-tetraenal 7, completing the eight-carbon homologation of benzaldehyde. Reaction of 9-phenyl-nona-(2E,4E,6E,8E)-tetraenal 7 with methyllithium in tetrahydrofuran afforded (3E,5E,7E,9E)-10-phenyl-deca-3,5,7,9-tetraen-2-ol 8. The product of the reaction described was employed in the synthesis of (3E,5E,7E,9E)-10-phenyl-deca-3,5,7,9-tetraen-2-one 9, which is known as navenone B, an alarm pheromone of the mollusk Navanax inermis.     

First report of anti-inflammatory chromenyl derivatives from the spineless cuttlefish Sepiella inermis

Abstract

The spineless cuttlefish Sepiella inermis encompasses a major share in the marine fisheries sector, and represents as a culinary delicacy in many cultures. Bioactivity-guided fractionation of methanol:ethyl acetate (MeOH:EtOAc, 1:1) extract of the edible parts of the species ensued in identification of two hexahydro chromenyl analogues namely, methyl 7-ethyl-hexahydro-8a-methyl-2H-chromene-4-carboxylate (1) and methyl 1-acetoxy-hexahydro-3-methyl-3-propyl-1H-isochromene-4-carboxylate (2). The isolated metabolites were checked for their radical scavenging and anti-inflammatory potentials by selective in vitro models. The isochromenyl derivative exhibited potential 2,2-diphenyl-1-picryl-hydrazil and 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (IC₅₀?<?0.45?mg mL^?1) radical-scavenging capacities along with pro-inflammatory cyclooxygenase-2 (COX-2) (IC₅₀ 0.75?mg mL^?1) and 5-lipoxygenase (5-LOX) (IC₅₀ 0.77?mg mL^?1) inhibitory activities. The titled compounds displayed the selectivity indices (IC₅₀ anti-COX-1/IC₅₀ anti-COX-2) greater than 1.25, in comparison with synthetic anti-inflammatory drug ibuprofen (0.44), which attributed to their greater selectivity towards inducible pro-inflammatory enzyme COX-2.     

曼氏无针乌贼胚胎发育形态及发育时序的研究

观察了室内培育的曼氏无针乌贼自然生产的受精卵形态和胚胎发育过程.结果表明,曼氏无针乌贼受精卵成乳头状,平均卵长10mm,平均卵宽5.5mm,受精卵外被黑色坚韧而富有弹性的三级卵膜,成串聚集一起成葡萄状.胚胎发育分为12个阶段：受精卵期、卵裂期、囊胚期、原肠胚期、初具形态期、腕分化期、心跳出现期、色素出现期、内骨骼形成期、尾腺出现期、缘膜形成期、孵化期.其胚胎大小从卵裂期开始增长,卵裂期胚胎长（3.40±0.12）mm,胚胎宽（3.29±0.14）mm,到孵化出膜前胚胎长达（8.17±0.33）mm,胚胎宽达（7.17±0.33）mm,增大了2倍左右.初具形态期各器官开始形成,胴部、头部、腕部开始分化.在19~21℃水温下,从受精卵到孵化出膜历时28~30d,初孵小乌贼仍挂着梨状卵黄囊,卵黄囊均长3.70mm,均宽2.75mm,在水中游动1~10min后就自动脱落,乌贼幼体一出膜就能喷墨,同时能开口摄食动物性饵料.     

微波消解ICP-MS法测定曼氏无针乌贼肉和海螵蛸中八种微量元素

采用微波消解技术,建立了一种测定头足类食药两用生物曼氏无针乌贼肉和海螵蛸中Cr,Mn,Cu,Zn,As,Cd,Hg和Pb等八种微量元素含量的ICP-MS法.测定元索校正曲线的相关系数都在0.997 3以上,样品分析结果的相对标准偏差在2.4%～8.7%之间,加标回收率在96.5%～106.3%之间,最低检出限在0.002～0.032μg·L~(-1)之间.研究结果表明:曼氏无针乌贼肉和海螵蛸中含有丰富的元素Cu和Zn,但是苇金属元素Cd和As含最也超过规定标准,因此曼氏无针乌贼进入市场时,需要对Cd和As含量进行严格的检查.研究结果不仅对曼氏无针乌贼质量控制具有指导意义,而且可为曼氏无针乌贼的养殖、资源利用及产品出口提供科学依据.     

Capillary zone electrophoretic determination of phenolic compounds in chess (Bromus inermis L.) plant extracts

A simple CZE method for quantification of phenolic compounds (vanillin, cinnamic, sinapic, chlorogenic, syringic, ferulic, benzoic, p-coumaric, vanillic, p-hydroxybenzoic, rosmarinic, caffeic, gallic and protocatechuic acids) in less than 10 min using 20 mM sodium tetraborate (pH 9.2) with 5% v/v methanol as a BGE and with UV detection at 254 nm is described. The LODs (3 S/N) ranged between 0.02 and 0.12 microg/ mL. Repeatabilities (RSDs) were 0.66-1.8 and 1.56-4.23% for migration times and peak areas (n = 5), respectively. The method was applied to the determination of phenolic compounds in chess (Bromus inermis L.) after Soxhlet extraction and purification of the crude extracts with SPE procedures. The results compared well with those obtained by liquid chromatographic method. B. inermis was found as a suitable model plant containing a broad spectrum of phenolic compounds in easily detectable concentrations and as a potential source of antioxidants.     

Study of electropolishing inhibition of steel using natural products as a green inhibitor in ortho-phosphoric acid

ABSTRACT

Anodic inhibition of steel in 8?mol?L^?1 H₃PO₄ was investigated in the absence and presence of different concentrations of extracts of Lawsonia inermis. An experimental measurement, including galvanostatic polarization studies, was done. The anodic corrosion rate and the inhibition efficiencies of the extract were calculated. The results obtained show that the inhibition was found to increase with increasing concentration of Lawsonia inermis extract. The inhibition actions of extracts are discussed on the basis of adsorption of Lawsonia inermis at the steel surface. Theoretical fitting of different isotherms were tested to clarify the nature of adsorption. Polarization curves revealed that Lawsonia inermis inhibitor acts as a corrosion inhibitor. The activation energy (E_a) as well as other thermodynamic parameters (ΔH*, ΔS*, ΔG*) for the inhibition process were calculated. These thermodynamic parameters show strong interaction between the inhibitor and the steel surface. The scanning electron microscope analysis study confirmed the adsorption of inhibitor molecules on the steel surface. The social organization and morphology of the extract were characterized by Fourier transform infrared spectroscopy.     

微生物Streptomyces griseus ACCT 13273对喹喏酸苷的羟基化代谢研究

Microbial transformation of a triterpene glycoside, quinovic acid 3-O-β-D-quinovopyranoside by Streptomyces griseus ACCT 13273 was achieved with the aim of generating new bio-active derivatives. Preparative-scale biotransformation with standard two-stage fermentation protocol afforded a new oxidized metabolite, as a result of the hydroxylation of the methyl group at C-30, which was difficult to achieve by chemical means. The metabolite was elucidated based on extensive NMR and high-resolution mass spectral analyses.     

1,2,4-trihydroxynaphthalene-2-O-β-D-glucopyranoside: A new powerful antioxidant and inhibitor of Aβ42 aggregation isolated from the leaves of Lawsonia inermis

Mounting evidence indicates free radicals as toxic species causing damage to human cells leading to the pathogenesis of many diseases such as neurodegenerative disease. Plant derived antioxidants are considered as promising strategy to prevent free radical toxicity. In this study, the crude extract (CE), 50%MeOH, Petroleum Ether (PE) and Ethyl acetate (EA) fractions of Lawsonia inermis leaves were investigated for their antioxidant activity and their ability to counteract amyloid-β₄₂ (Aβ₄₂) aggregation. Elution of the most bioactive fraction (EA) on silica gel column chromatography led to six sub-fractions. The most active sub-fraction (1) was further resolved on silica gel column chromatography. A new compound with powerful antioxidant and anti-Aβ₄₂ aggregation properties was purified and characterised by spectroscopic methods as 1,2,4-trihydroxynaphthalene-2-O-β-D-glucopyranoside (THNG). This finding suggests that the antioxidant and anti-Aβ₄₂ aggregation activities of L. inermis leaves are strongly correlated to this compound.