Chionanthus virginicus L.: phytochemical analysis and quality control of herbal drug and herbal preparations.

Root barks of Chionanthus virginicus L. are used in homeopathic medicines in the treatment of icterus and hepatitis. The objective of this study is to identify novel secoiridoids and lignans and to develop a simple and reliable HPLC method for the determination of oleuropein, phillyrin, total secoiridoids and total lignans for quality control and stability studies of C. virginicus herbal drug and preparations. Secoiridoids and lignans were purified by preparative HPLC. Compounds previously described were identified by HPLC according to their retention times and UV spectra. Structures of new compounds were determined by NMR. Two compounds namely excelside B and acetoxypinoresinol-4"-O-beta-D-glucoside are described for the first time in the drug. HPLC separation was performed on Symmetry C18 (Waters) by gradient elution using acetonitrile and 0.2% aqueous phosphoric acid. The method was validated for specificity, linearity, precision, accuracy, limits of detection and quantification for simultaneous determination of secoiridoids and lignans in herbal drug and herbal preparations as mother tinctures. The proposed HPLC method is linear in the range studied (r2 > or = 0.9989) for all the analytes. The method is precise with intra- and inter-day variations of less than 4%. The mean recoveries of the analytes range from 99.65 to 102.81%. The method is successfully applied to the quantification of nine compounds belonging to secoiridoids and lignans and for the stability studies of these compounds. The study allowed completing the phytochemical knowledge of C. virginicus. This simple developed assay could be used as tools for routine quality control of C. virginicus herbal drug and herbal medicinal products.

Lignans and secoiridoids from the root bark of Chionanthus virginicus L.: isolation, identification and HPLC analysis.

Five lignans, phillyrin (1), pinoresinol-beta-D-glucoside (2), pinoresinol di-beta-D-glucoside (3), phillyrin-2-O-beta-D-glucoside (6), phillyrin-6-O-beta-D-glucoside (7), and three secoiridoids, oleuropein (4), ligustroside (5) and angustifolioside B (8), have been isolated from the root bark of Chionanthus virginicus L. (Oleaceae), a raw material used in the commercial preparation of homeopathy tinctures. Compound 6 is a new lignan, and compounds 2, 3, 4, 5, 7 and 8 are described for the first time in the title plant. The structures of these compounds were elucidated by spectroscopic methods (NMR and HPLC-MS). An isocratic HPLC method for the rapid characterisation and quantification of the major constituents, 1 and 4, of the root bark is described and validated.

Repellency and toxicity of aromatic plant extracts against the mosquito Culex pipiens molestus (Diptera: Culicidae).

The insecticidal activities of essential oil extracts from leaves, flowers and roots of aromatic plants against fourth-instar larvae of the mosquito Culex pipiens molestus Forskal were determined. Extracts of Foeniculum vulgare Mill were the most toxic, followed by those of Ferula hermonis Boiss, Citrus sinensis Osbeck, Pinus pinea L, Laurus nobilis L and Eucalyptus spp with LC50 values of 24.5, 44.0, 60.0, 75.0, 117.0 and 120.0 mg litre(-1), respectively. Combination tests between the LC50 and the maximum sub-lethal concentration (MSLC) were determined. Over 20 major components were identified in extracts from each plant species tested. Five essential oils and nine pure components were studied for their repellency against mosquito bites. Terpineol and 1,8-cineole were the most effective against Culex pipiens molestus bites offering complete protection for 1.6 and 2 h, respectively.