Monoterpene composition of cortical oleoresin from different clones of Pinus sylvestris

Monoterpene composition of cortical oleoresin was determined in a number of 9-yr-old grafts of Scots pine (Pinus sylvestris), growing in a clone trial at two different levels of mineral nutrient supply. Variation between clones was considerable for some of the monoterpene constituents, indicating genetic control. In one of the clones, δ³-carene, α-terpinene and terpinolene were totally absent. The monoterpene composition was not significantly affected by the annual application of macro-nutrients.     

Tissue-specific regulation of volatile emissions moves predators from flowers to attacked leaves

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C31,-secodammarane-type triterpenoid saponins from the male flowers of Alnus pendula

Six C₃₁-secodammarane-type triterpenoid saponins, in addition to alnustic acid, were isolated from the male flowers of Alnus pendula. Two of these saponins were new and were shown to be the 12-O-(2′-O-acetyl)-β-d-xylopyranoside and the 12-O-(2′-O-acetyl)-β-d-glucopyranoside of alnustic acid, respectively, on the basis of their physico-chemical data.     

Cestric acid,a caffeic acid ester from Cestrum euanthes

Cestric acid, a new phenolic ester was isolated from leaves of Cestrum euanthes. By means of GC, HPLC, mass spectroscopy, GC/MS, and ¹³C NMR, it was shown to be an ester of caffeic acid with glucaric acid. The ester occurs as an equilibrium mixture of four isomers.     

Lupin alkaloids from flowers of Echinosophora koreensis

(?)-Methyl 12-cytisineacetate (2) was isolated from methanol extracts of fresh flowers of Echinosophora koreensis together with seven known lupin alkaloids. Ethyl 12-cytisineacetate (3) was also isolated from ethanol extracts of the same flowers. Compounds 2 and 3 were artifacts and (?)-12-cytisineacetic acid (4) is assumed to be the principal source of 2 and 3. The variations in alkaloid content during growth of the flowers and the seedlings were also examined.     

Hydroxytropane tiglates in the roots of Mandragora species

Roots of Mandragora autumnalis and M. vernalis contain hyoscyamine, hyoscine, cuscohygrine, apoatropine 3α-tigloyloxytropane and 3,6-ditigloyloxytropane. Belladonnine is present in the dried roots but could not be detected in fresh roots. No major differences were found in the alkaloids present in the two species. This is the first time the presence of tiglic acid esters has been reported in Mandragora species and the significance of this in the chemotaxonomy of the genus is indicated.     

Analysis of 3-indole carboxylic acid in Pinus sylvestris needles

3-Indole carboxylic acid (ICA) has been characterized as an endogenous constituent of Pinus sylvestris needles. Quantitative estimates of 3-indole acetic acid (IAA) and ICA, corrected for both sample losses and the conversion of IAA to ICA occurring during purification, indicate that Pinus needles contain 24.5 ± 6.5 ng IAA/g and 2.3 ± 0.4 ng ICA/g.     

Influence of temperature on the rhythmic emission of volatiles from Ribes nigrum flowers in situ

The floral volatiles of blackcurrant (Ribes nigrum) were collected in situ using the headspace technique. Eleven compounds were identified, including monoterpenes hydrocarbons and monoterpene ethers. The fragrance was emitted in a rhythmic manner, the maximum being in the middle of the photoperiod. Emission at 20°C was significantly higher than at 10°C. The rhythmic nature of emission seemed to cease under conditions of constant light. However, a slight rise in emission during the second period in continuous light may indicate a circadian control of emission. The significance of flower volatiles in relation to pollination is discussed.     

Two triterpenes from the flowers of Camellia japonica

Two new triterpenoids from the flowers of Camellia japonica have been identified as 3β,18β-dihydroxy-28-norolean-12-en-16-one and 18β-hydroxy-28-norolean-12-ene-3,16-dione. A large amount of 3β-hydroxy-28-noroleana-12,17-dien-16-one was also obtained.     

Scent chemistry and pollinator attraction in the deceptive trap flowers of Ceropegia dolichophylla

Ceropegia species (Apocynaceae, Asclepiadoideae) have pitfall flowers and are pollinated by small flies through deception. It has been suggested that these flies are attracted by floral scent. However, the scent that is emitted from Ceropegia flowers has not been studied using headspace and gas chromatography mass spectrometry methods. It has also been unclear whether or not the flowers are mimics of particular models that attract flies. In the present study, we determined the composition as well as the spatial and temporal patterns of floral scent emitted by C. dolichophylla. Furthermore, we determined the pollinators in the native (China) and non-native (Germany) range of this species, and tested the capability of the floral scent to attract flies in the non-native range. Our data demonstrate that the floral scent, which is emitted from morning until evening, primarily from the tips of the corolla lobes, consists mainly of spiroacetals and aliphatic compounds. Milichiid flies were common visitors/pollinators in the native as well as non-native range, and were attracted by floral scent in bioassays performed in the non-native range. The compounds emitted by C. dolichophylla are unusual for flowers, but are well known from insect pheromones and occur in the glandular secretions of insects. The milichiid flies that visit and pollinate the flowers are kleptoparasites that feed on the prey (haemolymph or other secretions) of predatory arthropods, e.g. spiders, to which they are attracted by scent. Our data thus suggest that the floral scent of C. dolichophylla mimics the feeding sites of kleptoparasitic flies.     

Cannabis sativa: volatile compounds from pollen and entire male and female plants of two variants, Northern Lights and Hawaian Indica

Sixty-eight compounds were identified by coupled gas chromatography and mass spectrometry (GC-MS) in the chemosphere of Cannabis sativa L. pollen and entire male and female plants of two cultivated varieties, Northern Lights and Hawaian Indica. Twenty-one and 28 substances, respectively, were present in pollen of the two forms. To conserve the natural composition of volatiles a delicate headspace method was employed. The two varieties represent different chemotypes which distinguish themselves, in the main quantitatively, in the setup of volatiles from pollen and entire male and female plants. Twenty compounds were monoterpenes, including the five major components: β-myrcene (E)-β-ocimene, terpinolene, β-pinene and limonene; 25 were sesquiterpenes, and the other 23 were of mixed biogenetic origin, including 3-methyl-1-butanol and benzylalcohol which occurred only in pollen; two pyrazines occurred only in Northern Lights females. Besides being of interest in natural products chemistry, the results should have relevance for plant systematics and for the pharmaceutical and technical applications of Cannabis . We demonstrate that the pollen has a distinct chemical character in possessing two exclusive volatiles, while lacking seven compounds occurring in males and females of both variants.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 387–397.     

Bitter phenylpropanoid glycosides from Conandron ramoidioides

A new bitter glycoside, conandroside and a known glycoside, acteoside were isolated from Conandron ramoidioides. On the basis of the chemical and spectral evidence, conandroside was shown to be 2-(3′,4′-dihydroxy-phenyl)-ethanol 1-O-β-D-xylosyl-(1 → 3)-β-D-(4-caffeyl)-glucoside.     

Flavonol glycosides from the flowers of Cucurbita pepo

Two new flavonol glycosides were isolated from the male flowers of Cucurbita pepo and their structures determined by UV, NMR and FDMS as rhamnazin     

Solid-phase microextraction of volatile compounds from flowers of two Brunfelsia species

Two plant species belonging to the genus Brunfelsia, commonly known as “Yesterday-Today-and-Tomorrow”, are closely related, however, differ by their flower fragrance. Flowers of Brunfelsia australis present a pleasant fragrance, whereas flowers of Brunfelsia pauciflora are scentless. SPME/GC/MS analysis on flower samples of both species of Brunfelsia indicated that flowers of B. australis emitted a fresh flowery fragrance, essentially comprising two monoterpenic compounds (linalool and (E)-ocimene). B. pauciflora, on the other hand, produced only a few sesquiterpenoids. These results are considered in an ecological and evolutionary context.     

Macrocyclic diterpene esters of the cytotoxic fraction from Euphorbia kamerunica

The ether-soluble resin of the latex of Euphorbia kamerunica was separated into a non-polar and a polar fraction by gradient elution column chromatography. From the non-polar fraction three macrocyclic diterpene esters were isolated by adsorption and partition preparative TLC methods. These compounds were identified as 3,7,8-triacetyl-ingol-12-tigliate,3,7-diacetyl-ingol-12-tigliate and ingol-tetra-acetate by means of spectroscopic data, together with hydrolysis and partial synthesis.     

Structures of verbascoside and orobanchoside,caffeic acid sugar esters from Orobanche rapum-genistae

The complete structural elucidation of the two caffeic acid sugar esters verbascoside and orobanchoside, has been realized by ¹H and ¹³C NMR studies. It has been demonstrated that verbascoside is β-(3′,4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl(1→3)-β-D-(4-O-caffeoyl)-glucopyranoside, and orobanchoside is β-hydroxy-β-(3′,4′-dihydroxyphenyl)-ethyl-O-α-L-rhamnopyranosyl(1→2)-β-D-(4-O-caffeoyl)-glucopyranoside.     

Halogenated monoterpenes of the red alga Microcladia

The red marine algae Microcladia borealis, M. californica and M. coulteri produce several unusual halogenated monoterpenes including violacene, plocamene-B, plocamene-C, and plocamane-D. The isolation of these terpenes along with a study of their variation in each Microcladia at different locations are described.     

Novel aspects of the flowers and floral pigmentation of two Cleome species (Cleomaceae), C. hassleriana and C. serrulata

Palely pigmented inflorescences of cultivated Cleome hassleriana Chodat (spider flower) have a unique two-toned appearance shown in the present study to be due to a loss of petal pigmentation within 24 h of anthesis, accompanied by an equally unique loss of petal mass. A similar loss occurs in deeply pigmented petals but is less evident to the eye because of the high initial content due to the presence, in the petal mesophyll, of globular anthocyanic vacuolar inclusions (AVIs). Inflorescences of the wild species, Cleome serrulata Pursh. (Rocky Mountain bee flower) are also two-toned because of the deeper pink colour of the unopened bud. No AVIs were seen. The pink colour of the bee flower petals is due to the same five acylated cyanidin glycosides as those previously isolated from mauve petals of spider flower. The structural pattern of the spider flower anthocyanins is shared with at least three genera of the Brassicaceae.     

Lipid and sterol composition of the pollen of the west african oilpalm, Elaeis guineensis

The lipid classes, fatty acid methyl esters and the sterols of oilpalm pollen were analysed. The neutral lipid fraction consisted of triglycerides, esterified and free sterols and trace amounts of hydrocarbons. Monogalactosyl and digalactosyl diglycerides, phosphatidyl choline, phosphatidyl inositol and phosphatidyl ethanolamine represented the polar lipids. The major fatty acids were linoleic, palmitic and linolenic acids together with small to trace amounts of oleic, stearic, arachidic, myristic, lauric, palmitoleic and margaric acids. Unsaturated fatty acids predominated over saturated ones in the ratio of 3:2. The 4-desmethyl sterols were the major phytosterols in the free form but they constituted a lower proportion of the sterols in the esterified state. 28-Isofucosterol was isolated and characterized as the principal sterol.