Shaft Corrêa Pinto

Isolation and Identification of cis-7- Hydroxycalamenene from the Essential Oil of Croton cajucara Benth.

Abstract During agronomical and chemical studies with Croton cajucara Benth. (Euphorbiaceae), a shrub native to the Amazon area possessing an essential oil rich in linalool, it was observed that some individuals of a germplasm bank produced an oil containing a hydroxylated sesquiterpene as major component (up to 44.3%). Originally misidentified as 5-hydroxycalamenene, the compound was further isolated and properly identified by 1H and 13C NMR as cis-7-hydroxycalamenene. Measured retention indices were 1759 (Ultra-1), 1804 (HP-5), 2212 (FFAP) and 2663 (Carbowax 20M).

Application of pH-zone-refining countercurrent chromatography for the separation of indole alkaloids from Aspidosperma rigidum Rusby.

Species of Aspidosperma (Apocynaceae) are characterized by the occurrence of indole alkaloids, but few recent reports on Aspidosperma rigidum Rusby chemical constituents were found. The present work shows the application of pH-zone refining countercurrent chromatography on the separation of alkaloids from the barks of A. rigidum. In this study, the dichloromethane extract was fractionated with the solvent system composed of methyl-tert-butyl ether and water with different concentrations of the retainer triethylamine in the organic stationary phase and formic or hydrochloric acids as eluters in the aqueous mobile phase, in order to evaluate the most suitable condition. In each experiment, from circa 200mg of the dichloromethane extract of A. rigidum, three major alkaloids were isolated and identified as 3α-aricine (circa 17mg), isoreserpiline (ca. 22mg) and 3β-reserpiline (ca. 40mg), with relative purity of 79%, 89% and 82% respectively, in a one-step separation of 2h. Two of them - 3α-aricine and isoreserpiline - were isolated and identified for the first time in this species.

Separation of acetins by counter-current chromatography

In this work we report the purification of a crude acetin mixture into mono-, di- and triacetin by countercurrent chromatography. The process was initially tested on a small, semi-preparative scale (0.5 g) to determine its efficiency. The process was then scaled up to accommodate 2.5 g of crude reaction products containing a mixture of the acetins. The solvent system ethyl acetate/n-butanol/water 1:0.2:1 was used in all separation procedures. Mono-, di- and triacetins were separated similarly in the semi-preparative and preparative runs.

Evaluation of the chemical composition of the essential oil from a Brazilian Poejo, Hesperozygis myrtoides (St. Hill ex Benth.) Epling at different collection periods and sites

Abstract Hesperozygis myrtoides is a native species from Cerrado and Atlantic Forest of Brazil. The essential oil from aerial parts of this plant, collected at different periods of the year, was obtained by hydrodistillation and analyzed by GC and CG-MS. The most abundant compounds were limonene (2.1–22.7%), isomenthone (14.3–47.7%), neo-isomenthol (1.8–4.4%), pulegone (19.8–57.3%) and isomenthyl acetate (0.3–14.3%). The chromatographic data were processed using hierarchical cluster analysis (HCA) and principal component analysis (PCA) based on the major compounds. The multivariate analyses (MVA) indicated that the variation of chemical composition of principal substances of H. myrtoides essential oil depends on the altitude. The enantiomeric distribution of (R)-(+)-pulegone and (+)-isomenthone were established for the first time for this essential oil by bidimensional GC-chiral analysis.

Chemical composition of the volatile fractions from wild and in vitro plants of Anemia tomentosa var. anthriscifolia (Pteridophyta)

Anemia tomentosa var. anthriscifolia is a very aromatic fern with ornamental potential. The major constituent of the volatile fraction of this plant is the triquinane sesquiterpene (-)-9-epi-presilphiperfolan-1-ol, which displays in vitro antibacterial activity against Mycobacterium tuberculosis. In order to investigate the chemical composition of this volatile fraction in relation to their triquinane sesquiterpenes upon in vitro multiplication, the tissue culture of this plant was established. Gametophytes and early sporophytes were successfully developed from spores inoculated in MS medium without growth regulators. Volatiles of both in vitro and wild plants were extracted by simultaneous distillation and extraction (SDE) and analyzed by gas chromatography/flame ionization detector (GC/FID) and GC–mass spectrometry (GC/MS). Twenty-seven constituents were evidenced in the volatiles of the wild plant, accounting for 93.4% of its total composition, whereas only seven constituents accounted for 97.0% of the total composition of the volatiles of the in vitro plants, respectively. The volatiles from the in vitro plants were composed mainly of monoterpenes (79%), whereas those of the wild plants comprised mostly sesquiterpenes (97.5%). The major constituents from in vitro plants are α-pinene (20.7%), trans-pinocarveol (31.0%) and pinocarvone (27.3%), whereas the major constituents from wild plants are silphiperfol-6-ene (11.7%), 9-epi-presilphiperfolan-1-ol (31.3%) and presilphiperfolan-8-ol (21.2%).

Anemia tomentosa var. anthriscifolia in vitro culture: sporophyte development and volatile compound profile of an aromatic fern

Anemia tomentosa var. anthriscifolia is an aromatic fern with a pleasant woody aroma and antimycobacterial activity. In this paper, we describe for the first time its spore-derived gametophyte development and the effect of indole-3-acetic acid and jasmonic acid on in vitro gametophyte/sporophyte development, as well as volatile compound production. Volatiles were obtained by simultaneous distillation and extraction (SDE) and analyzed by high resolution gas chromatography coupled with mass spectrometry. Spore-derived gametophytes were able to develop into sporophytes independently of the media culture composition, even when no plant growth regulator was added. Fifty different substances were detected in all in vitro A. tomentosa SDE extracts, while 20 were detected in the wild SDE plant extract. Monoterpenes were more prevalent (69.8–89.8%) than sesquiterpenes (9.4–28.7%) in in vitro plants, while sesquiterpenes represent 97.5% of the volatiles produced by the wild-grown plants. The major monoterpene components in in vitro plants were α-pinene (9.3–24.3%), trans-pinocarveol (20.6–27.9%), pinocarvone (15.4–25.1%) and myrtenyl acetate (6.4–12.3%). The triquinane sesquiterpenes silphiperfol-6-ene (0.6–2.9%), α-guaiene (0.5–2.5%), β-barbatene (1.1–3.9%) and 9-epi-presilphiperfolan-1-ol (2.5–5.6%) represent the most abundant sesquiterpenes. The changes in the monoterpene/sesquiterpene rates between micropropagated and wild plants are not related to the presence of JA or IAA in the media culture. Further studies are still needed to obtain a complete understanding of the factors leading to these results, which could be related to differences in the irradiance levels of in vitro plants versus those from a wild environment, as well as the developmental stage of the plants. This is the first report of the use of plant growth regulators on Anemia tomentosa in vitro culture development and their effects on volatile profiles.