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Plectranthus barbatus is largely used in the Northeast region of Brazil by the local population for treatment of digestive problems as substitute of boldo (Pneumus boldus). Phytochemical analysis of the leaf extracts of Plectranthus barbatus (Labiatae) cultivated in this region yielded two abietane diterpenoids, cyclobubatusin (1) and barbatusin (2) and a new one named 7beta-acetyl-12-deacetoxycyclobutatusin (3). The structures of the isolated compounds were established by spectral analysis, using mainly mass spectra and ¹H and 13CNMR (1D and 2D). These procedures permitted the assignment of all chemical shifts in the diterpenoids.

A new isoflavone named harpalycine and quercetin were isolated from the leaves and 3-hydroxy-4-isopentenyl-8,9-methyle-nedioxypterocarpan and betulinic acid from the roots of Harpalyce brasiliana. The structures were elucidated using spectroscopic methods, including 2D NMR techniques of the new isoflavone. Uma nova isoflavona denominada harpalicina e quercetina foram isoladas das folhas e 3-hidroxi-4-isopentenil-8,9-metilenodioxipterocarpano e ácido betulínico das raizes de Harpalyce brasiliana. As estruturas foram elucidadas usando métodos espectrométricos, inclusive RMN bidimensional (2D) da nova isoflavona.

The Plectranthus species (Lamiaceae) have been used in traditional medicine in several places around the world, including Brazil, to treat different diseases. P. grandis and P. ornatus, growing in north-eastern Brazil, were collected at four different times of day and the essential oils from the leaves were analysed by GC–MS. The oil of P. grandis contained mainly trans-β-caryophyllene (31.3–40.2%), germacrene D (12.5–24.5%) and eugenol (15.4%) and the oil of P. ornatus contained trans-β-caryophyllene (9.6–62.4%), eugenol (38.0%) and thymol (14.1%) as the major components. The oils were submitted to DPPH antioxidant assay. The oil of P. ornatus showed a higher antioxidant activity than that of P. ornatus, probably due to its higher yield of the phenolic compounds eugenol and thymol. Copyright © 2006 John Wiley & Sons, Ltd.

The aim of this work was to study the larvicidal activity of Lippia sidoides essential oil against Aedes aegypti larvae. The essential oil and its hydrolate (saturated solution of essential oil in water) were obtained by vapor extraction and their chemical composition determined by GL-chromatography coupled to mass spectroscopy. Bioassays were run with the essential oil, pure and diluted hydrolate and with their main constituents thymol and carvacrol. The results obtained showed that L. sidoides essential oil and its hydrolate have larvicidal action against the mosquito A. aegypti, causing an almost instantaneous mortality. Thymol, an alkylated phenol derivative and one of the major components of L. sidoides essential oil, was identified as the active principle responsible for the larvicidal action, causing 100% larval mortality at the lowest tested concentration of 0.017% (w/v). These results suggest that the essential oil of L. sidoides is promising as larvicide against A. aegypti and could be useful in the search of newer, more selective, and biodegradable larvicidal natural compounds to be used in official combat programs and at home.

The essential oils of Lippia alnifolia Schau. and L. aff. gracillis H.B.K. from northeast Brazil were analyzed by GC/MS. Z. alnifolia oil was found to contain limonene (47.2%) and piperitenone oxide (44.6 %) as major components. The oil of L. aff. gracillis contained p-cymene (14.5%), γ-terpinene (10.6%) and carvacrol (38.4%) as dominant constituents.

From the ethanolic extract of the heartwood of Cedrela odorata were isolated gedunin, 3β- O -β- d -glucopyranosyl-24-methyllenecholesterol, oleanonic acid, sitosterol, n -octacosanol and a new triterpene threo -23,24,25-trihydroxytirucall-7-en-3-one. Structural determinations of these compounds were made by spectrometric data. GC-MS analysis of the essential oil identified the sesquiterpenoids α-copaene, β-elemene, α-muurolene, calamenene, guayazulene, dihydroguayazulene, torreyol, γ-muurolene and α-cubebene.

Lippia sidoides Cham, and L. gracillis H.B.K. (Verbenaceae) are wild aromatic small trees or shrubs of Northeast Brazil vegetation. Chemical analysis of the oils obtained from the two plants by GC/MS revealed that L. sidoides contained thymol (73.1%), while L. gracillis contained carvacrol (47.7%) and p-cymene (19.2%) as main components.

Ocimum tenuiflorum L.f. (syn O. sanctum L.) (Labiatae) is an ayurvedic medicinal plant from India that was introduced in Northeastern Brazil in 1970. Oils produced by steam distillation and microwave distillation from leaves and inflorescences were analyzed by GC/MS and retention indices. The leaf oil contained eugenol (79.0–82.7%) and β-caryophyllene (7.9–9.8%) as major constituents, whereas the inflorescence oil was rich in eugenol (17.6–60.0%), β-caryophyllene (24.5–40.7%) and caryophyllene oxide (5.9–18.5%).

Variation of chemical composition of the essential oil of Ocimum gratissimum eugenol type was studied for 11 h during the daytime. Microwave oven technique was used for the serial extraction and the obtained oils were analysed by GC/MS. A considerable variation was observed in the eugenol yield, 98% at 12.00 am. to 11% at 05.00 p.m. These results show the influence of the solar light on eugenol production and can be useful to indicate the optimal time for collection of the plant.

The north-eastern region of Brazil comprises about one third of the country's territory. It is a semi-arid region with a flora rich in aromatic, toxic and medicinal plants. Screening of aromatic plants led to the investigation of about 2000 samples of essential oil from plants from the region and from abroad. Studies done by the Universidade Federal do Ceara and other research groups in the region discovered several new substances with distinct pharmacological activities. Recent examples are: schultezin, hydroxy-bisabolol, trans-annonene, (-)-hardwickic acid, trans-cascarillone, nor-cucurbitacins, oleanolic saponin and chalcone dimer. A social programme called the Living Pharmacy was created to teach poor people how to cultivate and use medicinal plants correctly. A project to develop interaction between the university and industry also arose from these studies.

The essential oil of Siparuna guianensis Aublet leaves collected during different months of the year were analyzed by GC/MS. (E)-Nerolidol was the major component of the oil of S. guianensis, collected in June during flowering. A large seasonal variation in the nerolidol content (0-99–3%) of S. guianensis oil was observed.

Essential oils from the leaves and inflorescences of Ocimum basilicum L. var purpurascens Benth, were obtained by steam distillation and using microwave distillation. Oils were investigated by GC and GC/MS. The main constituent in the leaf oils and inflorescence oil was linalool (39.3–79.6% and 81.5%).

The leaf oils of Turnera calyptrocarpa Urban and Turnera caerulea DC were characterized by GC/MS, Kovats indices and 13C-NMR analysis. Seventeen constituents were identified in the oil of T. calyptrocarpa, β-elemene (17.1%), β-caryophyllene (17.1%), γ-cadinene (13.2%) and curzerene (12.5%) being the major constituents. The main constituents found in the oil of T. caerulea were γ-cadinene (47.2%) and β-caryophyllene (32.1%).

Twenty-seven compounds have been characterized by GC/MS and Kovats indices in the essential oil of Tagetes erecta L. (Compositae). The major compounds are terpinolene (12.4%), (E)-β-ocimene (13.1%), piperitone (20.0%) and limonene (11.0%). The presence of indole among the minor compounds is somewhat surprising, since it was not reported before in this genus.

The essential oils obtained from the leaves of Wedelia paludosa DC. and Wedelia trilobata (L.) Hitch., were analyzed by GC/MS. α-Pinene was the chief constituent found in all samples of both oils in a yield above 30%. W. paludosa oil was also rich in β-pinene (10.3%), limonene (21.3%) and γ-muurolene (11.8%), while α-phellandrene (17.4%) and limonene (16.3%) were the other major components of W. trilobata oil.

The constituents of the essential oil obtained from flowerheads of Chamomilla recutita (L.) Rausch. plants growing around Medianeira city, in Parana State, Brazil, were analyzed by GC/MS. The major constituents identified in the oil were similar to those found in oils from other parts of the world. The Brazilian oil contained the following major components: bisabolol oxide B (23%), bisabolol oxide A (17%), (Z)-β-farnesene (16%), α-bisabolol (13%), chamazulene (8%) and chamo-spiroether (5%).

The neoflavonoids 7-hydroxy-5-methyl-4-(4’-methoxyphenyl)-3,4-dihydrocumarin (1), 5-hydroxy-7-methyl-4-(4’-methoxyphenyl)-3,4-dihydrocoumarin (2), 5-methyl-7-O-coumaroyl-4-(4’-methoxyphenyl)-3,4-dihydrocoumarin (3), 5-hydroxy-4-(4’-methoxyphenyl)-a-pirano-(6",5":7,8)-3,4-dihydrocoumarin (7), and 7-pentadecyl-4-(4’-methoxyphenyl)-3,4- dihydrocoumarin (8) were synthesized via the AlCl3-catalyzed condensation of 4-methoxycinnamic acid chloride with orcinol, 5,7-dihydroxycoumarin and hydrogenated cardanol. The compounds were characterized on the basis of their ¹H- and 13C-NMR spectroscopic properties, including nOe difference spectroscopy. Os neoflavonóides 7-hidroxi-5-metil-4-(4’-metoxifenil)-3,4-diidrocumarina (1), 5-hidroxi-7-metil-4-(4’-metoxifenil)-3,4-diidrocumarina (2), 5-metil-7-O-cumaroil-4-(4’-metoxifenil)-3,4-diidrocumarina (3), 5-hidroxi-4-(4’-metoxifenil)-a-pirano-(6",5":7,8)-3,4- diidrocumarina (7) e 7-pentadecil-4-(4’-metoxifenil)-3,4-diidrocumarina (8) foram sintetizados por condensação, catalisada pelo tricloreto de alumínio, entre o cloreto do ácido 4-metoxicinâmico com orcinol, 5,7-dihidroxicumarina e cardanol hidrogenado. Os produtos das reações foram caracterizados com base nos dados espectrais de RMN ¹H e 13C, usando-se principalmente a técnica de espectroscopia nOe diferencial.

Ocimum basilicum L. occurs everywhere in several forms, varieties and chemotypes whose essential oils presents marked variation on chemical composition. A new analysis of O. basilicum, O. basilicum var. minimum L. and O. basilicum var. purpuracens Benth. growing in north-eastern Brazil showed that O. basilicum var. minimum represented a true estragole chemotype, while the other two species analysed may be considered linalool chemotypes. Copyright © 2002 John Wiley & Sons, Ltd.

Essential oils from the leaves, fruit and resin of Protium heptaphyllum were analyzed by GC/MS from a sample collected in Crato-Ceara, Brazil. The major constituents identified in the leaves were mono and sesquiterpenes such as myrcene (18.6%), β-caryophyllene (18.5%) whereas oils from resin and fruit contained mainly monoterpenes such as α-pinene (10.5%), limonene (16.9%), α-phellandrene (16.7%), and terpinolene (28.5%) in the resin oil, and α-pinene (71.2%) in the fruit oil

The essential oil from inflorescence, fruit, bark and leaves of Croton lanjouwensis Jablonski was analyzed by GC/MS. The major constituents found in the leaf oil α-pinene (26.6%) and α-phellandrene (8.5%); in the fruit oil linalool (14.5%) and β-caryophyllene (190%); in the inflorescence oil α-pinene (28.4%) and linalool (26.7%) and in the bark oil α-pinene (72.2%).

The chemical composition of steam distilled oil of Erichtites hieracifolia was examined by GC/MS. The main compounds were found to be α-phellandrene (41.2%), p-cymene (22.1%), β-caryophyllene (7.%), camphor (5.4%), cis-ascaridole (10.0%) and α-phellandrene epoxide (1.0%).

The leaf and inflorescence oils of Ocimum micranthum Willd. were investigated by GC (retention time data), GC/MS and 13C-NMR spectroscopy. The main constituents in the leaves were eugenol (44.8%) and β-caryophyllene (14.7%), whereas in the inflorescence elemicin (32.9%) and eugenol (14.0%) were the major compounds

The oil from leaves of Guazuma ulmifolia Lam. was analyzed by GC and GC/MS. The major constituents found were precocene I (56.0%), β-caryophyllene (13.7%) and (2Z,6E)-farnesol (6.6%).

The oil obtained by steam distillation of the leaves of Acanthospermum australie DC was analyzed by a combination of GC/MS, retention indices and 13C-NMR spectroscopy. The major components found in the oil were β-caryophyllene (16.0%), β-elemene (14.4%), γ-cadinene (13.0%), germacrene A (10.1%) and δ-cadinene (5.5%).

Steam distillation of leaves of the Brazilian shrub Zanthoxylum gardneri Engl, gave an essential oil in 0.3% yield. GC/MS of the oil revealed the presence of (E)-nerolidol (81.5%) as the major component. Six other sesquiterpenoid constituents were also identified in the oil.

From the root bark of Guettarda angelica were isolated 3- O -β- d -glucopyranosyl-quinovic acid and its aglycone. The root wood gave the same glucoside, rotundic acid, hederagenin and 3β,23-dihydroxyurs-12-en-28-oic acid.

From branches of Bursera leptophloeos five flavonoids were isolated: 8-(3″-hydroxy-3″-methylbutyl)-5,7,4′-trihydroxydihydroflavonol, 6″,6″-dimethyldihydropyran (2″,3″:7,8)-5,4′-dihydroxydihydroflavonol, 8-(3″-hydroxy-3″-methylbutyl)-5,7,4′-trihydroxyflavonol, 6″,6″-dimethyldihydropyran (2″,3″:7,8)-5,4′-dihydroxyflavonol, 8-(γ,γ-di-methylallyl)-5,7,4′-trihydroxyflavonol, and two new related compounds 8-(γ,γ-dimethylallyl)-5,7,4′-trihydroxydihy-droflavonol and 5″-isopropenyldihydrofuran-(2″,3″:7,8)-5,4′-dihydroxydihydroflavonol.

The essential oils from Vanillosmopsis arborea Baker grown in Brazil were analyzed by capillary gas chromatography and mass spectrometry. β-Caryophyllene accounted for 23 percent of the oil extracted from the leaves, α-bisabolol for 70 percent of the oil extracted from the bark after steam distillation and more than 95 percent of the oil extracted from wood with hexane. Twelve more compounds were identified in the former oil and 11 more constituents were identified in the oil extracted from barks.

Centratherumpunrtatum Cass., which is known locally as perpetua roxa, is a member ofthe Compositae family commonly found throughout Northeartern Brazil. The oil of C. pwnctatum, which was analyzed by a combination of gc/ms, was found to contain: a-pinene (1.8%) a-humulene (2.4%) sabinene (2.2%) caryophyllene (11.1%) P-pinene (9.1%) y-cadinene (8.6%) p-cymene (0.8%) y-muurolene (1.7%) limonene (1.4%) 6-cadinene (17.9%) P-cubebene (2.6%) germacrene D (5.7%) a-copaene (5.6%) 6-cadinol (1.1%) fenc hone (1.7%) Previously ( l ) , a-hurnulene, caryophyllene, gerrnacrene D, and bicyclogermacrene had been identified as components of this above-ground plant