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Investigations with solid sampling gaschromatography of separate leaves and of hydrodistilled oil of Juniperus communis L. var. saxatilis Pall. growing in Norway at an altitude of 1000-1300 m above sea level, showed a terpinen-4-ol content varying from traces to about 1 % in separate leaves and up to 16-17% in hydrodistilled oil of uncomminuted leaves and twigs.

The essential oils from herb samples of Salvia coccinea Juss. ex Murr. were analysed by GLC, LSC and GC-MS. The plant material was collected from the same location in Ile-Ife, Nigeria, in three consecutive years. About 40 components including polynuclear aromatic compounds and their alkyl derivatives were identified in some oil samples. Their major components were acenaphthene (18%), trans-hex-2-enal (11%) and globulol (11%) in 1987, globulol (65%) and aromadendrene (11%) in 1988, and 2,5-dimethoxy-p-cymene (29%) and globulol (16.5 %) in 1989. The polynuclear aromatic compounds detected most likely originate in the plants.

Capillary GC analysis of the essential oils of Ocimum basilicum var. canum Sims and O. gratissimum L. grown on Aruba showed that O. basilicum var. canum belonged to the methyl cinnamate type. Half of the material of O. gratissimum belonged to the methyl cinnamate chemotype and the other half contained sesquiterpene hydrocarbons and varying amounts of eugenol as the main volatile components, indicating the existence also of a sesquiterpene hydrocarbon-eugenol chemotype of O. gratissimum.

The essential oil isolated from aerial parts of Hyptis spicigera Lam., used for example in baths in northern Nigeria, was analysed by capillary GC. Forty‐three components of the oil were identified, among which many occurred in small quantities. The identity of the components was confirmed by GC–MS using an ion trap detector. The oil was characterized by a high content of I²â€caryophyllene (68%) and the presence of C16 and C18 fatty acid methyl esters. The present paper describes the analysis of the essential oil of H. spicigera, family Lamiaceae, grown in Nigeria. Neither phytochemical nor pharmacological studies on the plant have been reported previously.

Capillary GC analysis of the essential oil of Hyptis suaveolens Poit. grown on Aruba showed high contents of 1,8-cineole (27-38%) and sabinene (12-18%). The oil showed a strong antimicrobial activity against Staphyloccocus aureus.

Capillary GC of the essential oil of Cordia cylindrostachya Roem. & Schult. grown on Aruba showed a high content of tricyclene (ca. 58%), α-pinene (ca. 11%) and camphene (ca. 12%). The rest—about 20% of the total oil—consisted of 35 components, most of which were identified. Most of them occurred in amounts of less than 1%. The oil showed weak antibacterial and antifungal activities.

Treatment of suspension cultures of some Tabernaemontana species (Apocynaceae) with elicitors (e.g. cellulase, Candida albicans) result in a rapid de novo production of antimicrobial active triterpenes. The triterpenes are identified as ursene carboxylic acid derivatives. These triterpenes are not produced by an elicited cell suspension culture of Catharanthus roseus, another Apocynaceae.

From ASPIDOSPERMA EXCELSUM, rootbark, which has previously been shown to exhibit antimicrobial activity, 6 antimicrobial active alkaloids were isolated and identified: 11-methoxytubotaiwine, ochrolifuanine A, tetrahydrosecamine, 16-demethoxycarbonyltetrahydrosecamine, 16-hydroxytetrahydrosecamine and 16-hydroxy, 16-demethoxycarbonyltetrahydrosecamine. The minimum inhibitory concentration was determined for some of the alkaloids, using BACILLUS SUBTILIS as test organism. Didemethoxycarbonyltetrahydrosecamine was also shown to exhibit antimicrobial activity. No activity against gram negative bacteria could be found for the alkaloids by means of biograms. The site of demethoxycarbonylation in demethoxycarbonyltetrahydrosecamine was established as C-16. The structures of the two new secamine type alkaloids, 16-hydroxytetrahydrosecamine and 16-hydroxy,16-demethoxycarbonyltetrahydrosecamine were determined by means of their spectral data. During the isolation of the antimicrobially active alkaloids some inactive alkaloids were also isolated: compactinervine, N a -acetylaspidospermidine, O-dimethylaspidospermine, aricine, yohimbine and O-acetylyohimbine.

The composition of the essential oil from Hemizygia welwitschii twigs was analyzed by means of GLC, LSC and GC/MS. The portion investigated so far consisted of 51% sesquiterpene hydrocarbons, 17% monoterpene hydrocarbons, 17% oxygen-containing sesquiterpenes, 6% oxygencontaining monoterpenes and 2% oxygen-containing, straight chain aliphatic compounds. The main components were β-caryophyllene (35%) and trans-α-bergamotol (11%); this is the first reported occurrence of the latter compound in Lamiaceae. The composition of the oil of H. welwitschii has not been reported previously. Additionally, 30–40% diterpenes were detected in the total oil.

The essential oil from herb of Ducrosia anethifolia (DC.) Boiss., growing wild in Iran, was investigated by LSC, GLC and GC-MS. The oil consisted mainly of aliphatic compounds. alpha-Pinene, myrcene and limonene were main components of the hydrocarbons present in the oil, while n-decanal, n-dodecanal, n-decanol, trans-2-dodecenal, and cis-chrysanthenyl acetate were the major oxygen-containing constituents. The oil and the main oxygen-containing aliphatic components showed a remarkable antimicrobial activity against gram-positive bacteria, a yeast, and some dermatophytes.

From callus cultures of Cinchona ledgeriana seven known anthraquinones, purpurin, anthragallol-1,2-dimethylether, anthragallol-1,3-dimethylether, rubiadin, 1-hydroxy-2-hydroxymethylanthraquinone, 1-hydroxy-2-methylanthraquinone and morindone-5-methylether (or 1,7-dihydroxy-8-methoxy-2-methylanthraquinone), and eight new anthraquinones, 5,6-dimethoxy-1-(or -4-)hydroxy-2-(or -3-)hydroxymethylanthraquinone, 5-methoxy-2-(or -3-)methyl-1,4,6-trihydroxyanthraquinone, 2-hydroxy-1,3,4-trimethoxyanthraquinone, 4-methoxy-1,3,5-trihydroxyanthraquinone, 1,4-dimethoxy-2,3-methylenedioxyanthraquinone, 1,3-dihydroxy-4-methoxyanthraquinone, 1,3-dihydroxy-2,5-dimethoxyanthraquinone and 2,5-(or 3,5-)dihydroxy-1,3,4-(or -1,2,4-)trimethoxyanthraquinone have been isolated.

rz For-the analysis of quaternary alkaloids, paper c~xGIIIG such separations can o& be made by use of very polar solvent systems. The ciassical solvent systems of butanol, water and acetic or formic acid may be used in co~ectioo with thin layers of silica gel_ The disadvantage of such systems is the rather long development time of the chromatograms and the long saturation time of the chrGmato_maphy tanks (24 h). The bisquatemary curare afkaloids have very low R, values in such solvent systems. Other TLC systems were therefore required for the analysis of this type of alkaloid. We found that the solvent systems described by Jane6 for high-speed liquid chromato_mphy of drugs of abuse on silica gel cohunns were also useful for TLC separations of quaternary alkaloids and alkaloid N-oxides. The solvent systems were aqueous methanol solutions of ammonium nit-ate of various concentrations.

The use of an agar diffusion method for the optimization of the phytohormone concentrations in growth media for plant cell cultures was studied. The method allows a rapid determination of both growth-supporting levels as well as toxic levels of the phytohormones. These levels were determined for aTabernaemontana divaricata cell line and the results could be extrapolated to suspension cultures.

The essential oils isolated from foliage of various clones of x Cupressocyparis leylandzi were analyzed by gas chromatography to determine whether the oils could be used as aids in clonal identification. Several botanical gardens supplied foliage which was submitted to hydrodistillation. The oils were isolated under standardized conditions and then analyzed. Comparison of the oil components (mostly monoterpene hydrocarbons) revealed that it is possible to identify, on the basis of the composition of the monoterpene hydrocarbon mixture, clones 1–6 as a group and clones 10 and 11 individually. The composition of the oils from foliage of the widely propagated clones 1,2, 10 and 11 is given in more detail.

From callus cultures of Cinchona pubescens seven known anthraquinones, alizarin-2-methylether, anthragallol-1,2-dimethylether, purpurin, purpurin-1-methylether, 1-hydroxy-2-hydroxymethylanthraquinone, 2-hydroxy-1,3,4-trimethoxyanthraquinone and 2,5-(or 3,5-)dihydroxy-1,3,4-(or -1,2,4-)trimethoxyanthraquinone, and five new anthraquinones, 2-hydroxy-1,3,4,6-(or -1,3,4,7-)tetramethoxyanthraquinone, 1,6-(or 1,7-)dihydroxy-2-methylanthraquinone, 5-hydroxy-purpurin-1-methylether, 4,6-(or 4,7)-dihydroxy-2,7-(or -2,6-)dimethoxyanthraquinone and 6,7-dihydroxy-1-methoxy-2-methylanthraquinone have been isolated.

Three alkaloids of the stem bark of Strychnos dolichothyrsa Gilg ex Onochie et Hepper (Loganiaceae) were isolated and identified as caracurine V and its mono- and di-N-oxide by comparison with synthesized compounds. 13C-NMR was used to confirm the structure of the N-oxides. The muscle relaxant activity and the toxicity of the N-oxides were less than those of caracurine V.

The taxonomy, phytochemistry, ethnobotany, and pharmacology of the genus Tabernaemontana L. (Apocynaceae) is reviewed. The genus is currently being revised taxonomically; most of the segregate genera are being reunited with it and the number of species that will ultimately be recognized will probably be about 100. All the names encountered in the chemical and ethnobotanical literature have been evaluated as far as possible, and a list is presented of the recognized species and their synonyms. The biogenesis and classification of the indole alkaloids found in Tabernaemontana species is set out and some problems in the determination of their stereochemistry are discussed. To facilitate access to the information, three lists have been compiled: the alkaloids in alphabetical order; the alkaloids in order of increasing molecular weight; and the alkaloids grouped according to their biogenetic classification, together with the species and plant part(s) in which they are known to occur. Biogenetic and chemotaxonomic aspects are briefly considered. A table of the non-alkaloidal constituents is also included. The ethnobotany of individual Tabernaemontana species is outlined and an overall assessment made. Likewise, information on the pharmacology of crude extracts and individual alkaloids from Tabernaemontana species has been assembled and appraised.

A review is presented which shows the vegetable kingdom as an almost inexhaustible reservoir of potential drugs. Some historical aspects about the use of plants and their constituents in medicine are dealth with. A number of problems connected with the search for new prototype drugs of biological origin is reported as well as modern methods used in this promising research. Some examples are given concerning recent results of investigations of plants used in traditional and modern medicine in China. Special attention is paid to the present role of natural products in therapy: as biologically active compounds as such, as starting materials for (semi)synthetic drugs and, last but not least, as source of inspiration or as models for the synthesis of new drugs with better therapeutic, chemical or physical properties than the original compounds.

The isolation of 18 indole alkaloids from a whole plant extract of TABERNAEMONTANA ELEGANS is described. Five new and 13 known alkaloids were isolated and identified. The five new alkaloids are tabernaemontaninol, dregaminol, dregaminol-methylether, 3- R/S-hydroxy-tabernaelegantine B and 3-methoxy-tabernaelegantine C. The other alkaloids are apparicine, 16- S-hydroxy-16, 22-dihydro-apparicine, tubotaiwine, vobasine, vobasinol, dregamine, tabernaemontanine, iso-voacangine, 3- R/S-hydroxy-conodurine, tabernaelegantine A, B, C and D.

The essential oil of OCIMUM KILIMANDSCHARICUM Guerke, growing wild in Rwanda, was investigated by LSC, GLC and GC-MS. The oil contained 62% 1.8-cineole, indicating the occurrence of a new chemotype of the species concerned. In addition to 1.8-cineole, 16 oxygen-containing compounds and 14 monoterpene hydrocarbons were identified, of which limonene and beta-pinene were the main components. Most of the constituents were not previously known to be present in the essential oil of O. KILIMANDSCHARICUM.

A review is given of the literature on the antimicrobial activity of various indole alkaloids. The data are briefly discussed. A screening was performed of a series of plants belonging to the indole alkaloid rich plant families Apocynaceae and Loganiaceae, 25 materials representing 14 Apocynaceae species and 54 materials representing 41 Strychnos species were investigated. No activity against the yeast or the fungus, used as test organisms was found. A number of extracts showed activity against the gram-positive test organisms, 4 species showed activity against gram-negative bacteria.

NTEZURUBANZA, L., SCHEFFER, J. J. C. & SVENDSEN, A. B., 1988. Composition of the essential oils of Ocimum urticifolium (Lamiaceae) chemotypes grown in Rwanda. Leaves and flowers of 48 specimen of Ocimum urticifolium (synonym: O. suave), Lamiaceae, were collected in different parts of Rwanda. The volatile components of each specimen were isolated by hydrodistillation under standardized conditions, and the 48 essential oils analysed by thin-layer chromatography. This preliminary analysis showed six different oil compositions. Thereafter, six oil samples were fractionated by liquid—solid chromatography. The fractions thus obtained, and all other oil samples were then analyzed by capillary gas chromatography. In this way 46 compounds were identified in the various oil samples. Eight components, which amounted to more than 10% in at least one oil sample, were used to characterize the oils. Twelve oil types were distinguished, three of which were dominated by one component only: eugenol, methyleugenol and transmethylisoeugenol respectively. The other types were more complex. In some parts of Rwanda almost one oil type seemed to occur, whereas in other areas a more heterogeneous collection of types was found. Eugenol was quantitatively most important in 31 of the 48 oil samples, in 22 of which this component amounted to more than 50%.

ADSERSEN, A. & SVENDSEN, A. B., 1986. A comparative study of Scalesia species (Asteraceae) by gas chromatographic analysis of the monoterpene hydrocarbons of their essential oils. The monoterpene hydrocarbons of the essential oils of 13 species of Scalesia, Asteraceae, endemic to the Galapagos Islands, were analysed by gas chromatography to determine whether the composition of these compounds could show any characteristics for the various species. Marked differences in the monoterpene hydrocarbon patterns of the Scalesia species investigated were observed. Whereas a-pinene was usually found in amounts of 30–50%, Scalesia villosa contained only 12%. Sabinene usually occurred in amounts of 10-1.5%, but S. divisa and S. affinis contained about twice as much. The limonene content was usually less than 1%, but S. microcephala, S. baurii and S. affinis contained amounts varying from about 2% to 9.5%.

Natural abundance 15N-NMR spectra were obtained from quinidine, quinine and epiquinidine. Correlation of the 15N chemical shifts with X-ray studies and minimal energy conformer calculations, reported previously, enabled definite conclusions about the solution conformations of these alkaloids. Also the protonation of quinidine in CDCl3 was studied. It was determined that the first protonation occurs on the quinuclidine nitrogen and not on the quinoline nitrogen as was reported by Yanuka et al.1

Twenty-three alkaloids and five steroids and triterpenes have been isolated and identified from the root bark and stem bark of a Nigerian Tabernaemontana pachysiphon . The following bases have not previously been obtained from this species: isositsirikine, 16-epiisositsirikine, normacusine B, 16-epiaffinine, anhydrovobasindiol, tubotaiwine, ibogaline, isovoacangine, voacamine, lochnericine, 3 R -hydroxyconopharyngine, 3 S -hydroxyconopharyngine and 11-demethylconoduramine, the last three being new alkaloids. The dimeric indole alkaloids and 3 R/S -hydroxyconopharyngine were shown to possess strong antibacterial activity against Gram-positive bacteria and the dimers against Gram-negative bacteria also.