Nilce V. Gramosa

Volatile Constituents of Copaifera langsdorffii from the Brazilian Northeast

Abstract GC/MS analysis of the hydrodistilled essential oils from leaves, root bark, fruit peel, trunk bark, trunk wood, root wood and fruits of Copaifera langsdorffii Desf. obtained in 0.04%, 0.01%, 0.7%, 0.003%, 0.008%, 0.07% and 0.3% yield, respectively, and also from copaiba balsam (7.3%), allowed the identification of 40 different constituents. The major compounds were: leaf and fruit oils: β-caryophyllene (16.6% and 14.8%) and γ-muurolene (25.2% and 29.8%); fruit peel oil: caryophyllene oxide (47.3%); root wood oil: caryophyllene oxide (40.5%) and 4-α-copaenol (17.6%); root bark oil: caryophyllene oxide (30.7%) and kaurene (8.2%); trunk wood oil: γ-muurolene (8.3%), caryophyllene oxide (31.0%) and kaurene (30.2%); trunk bark oil: β-bisabolol (30.5%), kaurene (16.7%) and kaurenal (31.9%); copaiba balsam oil: β-caryophyllene (53.3%).

Solubilisation capacity of Brij surfactants

The aim of this study was to investigate the potential of selected Brij non-ionic surfactants for enhancing the solubility of poorly water-soluble drugs. Griseofulvin was selected as a model drug candidate enabling comparisons to be made with the solubilisation capacities of other poly(ethylene oxide)-based copolymers. UV/Vis and (1)H NMR spectroscopies were used to quantify the enhancement of solubility of griseofulvin in 1 wt% aqueous micellar solutions of Brij 78 (C(18)H(37)E(20)), Brij 98 (C(18)H(35)E(20)) and Brij 700 (C(18)H(37)E(100)) (where E represents the OCH(2)CH(2) unit of the poly(ethylene oxide) chain) at 25, 37 and 40 °C. Solubilisation capacities (S(cp) expressed as mg griseofulvin per g Brij) were similar for Brij 78 and 98 (range 6-11 mg g(-1)) but lower for Brij 700 (3-4 mg g(-1)) as would be expected for the surfactant with the higher ethylene oxide content. The drug loading capacity of micelles of Brij 78 was higher than many di- and triblock copolymers with hydrophilic E-blocks specifically designed for enhancement of drug solubility.

Constituintes químicos dos frutos de Copaifera langsdorffii Desf.

Phytochemical investigation of the hexane extract of fruit shells of Copaifera langsdorffii Desf. (Caesalpinioideae) afforded ent-kaur-16-en-19-oic acid, polyalthic acid, nivenolide and the mixture of caryophyllene oxide and ent-kaur-16-en-19-oic acid. The chloroform extract of unripe seeds led to the isolation of coumarin and the GC/MS analysis of the extract allowed the identification of 81.8% of the fatty acid composition after hydrolysis followed by methylation. The main fatty acid identified was oleic acid (33.1%). The isolation of all secondary metabolites was accomplished by modern chromatographic methods and the structure determination was accomplished by spectrometric methods (IR, MS, NMR 1H and 13C).

Matrix‐assisted diffusion‐ordered spectroscopy: choosing a matrix

Diffusion‐ordered spectroscopy (DOSY) is an important technique for separating the NMR signals of the components in a mixture, and relies on differences in diffusion coefficient. Standard DOSY experiments therefore struggle when the components of a mixture are of similar size, and hence diffuse at similar rates. Fortunately, the diffusion coefficients of solutes can be manipulated by changing the matrix in which they diffuse, using matrix components that interact differentially with them, a technique known as matrix‐assisted DOSY. In the present investigation, we evaluate the performance of a number of new, previously used, and mixed matrices with an informative test mixture: the three positional isomers of dihydroxybenzene. The aim of this work is to present the matrix‐assisted DOSY user with information about the potential utility of a set of matrices (and combinations of matrices), including ionic and non‐ionic surfactants, complexing agents, polymers, and mixed solvents. A variety of matrices improved the diffusion resolution of the signals of the test system, with the best separation achieved by mixed micelles of sodium dodecyl sulfate and cetyl trimethylammonium bromide. The use of mixed matrices offers great potential for the analyst to tailor the matrix to a particular sample under study.

Constituintes químicos voláteis das folhas e galhos de Zanthoxylum syncarpum Tull.

The essential oils of the leaves and twigs from Zanthoxylum syncarpum Tull. were examined by GC/MS and GC-FID. Variation in the oil composition relative to the harvesting time was also described. The major components in the leaves oils were limonene (23.1-47.3%) and myrcene (4.8-10.8%). In the oils of twigs, the main components were ar-curcumene (12.8-18.1%), E-β-farnesene (9.1-9.7%) and β-caryophyllene (9.2-9.3%). This paper describes for the first time the composition of the essential oil of the twigs from Z. syncarpum.

Chemometric analysis of NMR and GC datasets for chemotype characterization of essential oils from different species of Ocimum

The genus Ocimum (Labiatae) comprises 30 species found in tropical and subtropical regions of the planet, of which species O. basilicum L. and O. gratissimum are widely used in food and traditional medicine. Phytochemical studies on Ocimum have revealed a number of essential oil chemotypes, for example, eugenol, methyl chavicol, linalool, and methyl cinnamate. Since essential oils are commercially assessed according to their content, the aim of this study was to develop a simple and precise method for their qualitative and quantitative analysis using NMR spectroscopy combined with chemometrics. Seven essential oils from different species of Ocimum, an unknown sample, and a commercial sample were evaluated and the results compared to those from established and precise GC-MS and GC-FID methods. Chemometric evaluation from both 1H NMR and GC-MS data revealed three chemotypes: eugenol for O. gratissimum, O. micranthum, and O. tenuiflorum; estragole for O. basilicum, O. basilicum var. purpuracens, and O. selloi; and methyl cinnamate for O. americanum. The unknown and commercial species were classified as cinnamate and eugenol chemotypes, respectively. Despite the corroborating results, the chemometric analysis revealed the higher robustness (better adjustment) of the 1H NMR model compared to the GC-MS method in terms of certain statistical parameters. The 1H NMR method allows for the detection and quantification of organic compounds in a complex mixture without the need for certified standard compounds. Although GC-MS and GC-FID were able to detect five compounds not observed by NMR spectroscopy, the four most important metabolites (eugenol, estragole, methyl cinnamate, and eucalyptol) were more readily detected and quantified by 1H NMR.

Constituintes químicos voláteis e não-voláteis de Moringa oleifera Lam., Moringaceae

Phytochemical analysis of the ethanol extract from leaves of Moringa oleifera Lam., Moringaceae, yield the benzylnitriles: niazirine, niazirinine and 4-hydroxyphenylacetonitrile, while of fruit shells only octacosane was isolated. The essential oils from leaves, flowers and fruits were examined by gas chromatography-mass spectrometry. The major constituents identified were: phytol (21.6%) and thymol (9.6%) in the leaves oil, octadecane (27.4%) and hexadecanoic acid (18.4%) in the flowers oil, docosane (32.7%) and tetracosane (24.0%) in the fruits oil. The structures of all compounds were identified by spectroscopic analyses (NMR, IR and MS). 4-hydroxyphenylacetonitrile is reported for the first time to the Moringa genus and the essential oils of flowers and fruits are reported for the first time to the species M. oleifera.

Volatile Components of the Essential Oil From Bauhinia ungulata L.

Abstract Air-dried leaves of Bauhinia ungulata L. were submitted to volatile oil isolation by hydrodistillation to produce an oil in 0.007% yield. The oil obtained was examined by gas chromatography (GC-FID) and gas chromatography/mass spectrometry (GC/MS). Thirteen compounds comprising 95.9% of the total peak area were identified. The main constituents identified were spathulenol (47.7%) and caryophyllene oxide (18.3%).

Volatile Constituents Isolated from Capparis flexuosa of Brazil

Abstract Essential oil analysis of Capparis flexuosa (Capparaceae) from Brazil allowed us to characterize 3-methyl-3-buteneisothiocyanate, 4-methyl-4-pentenenitrile and butyl isothiocyanate. Structure determinations were established by spectroscopic analysis (IR, MS, NMR) and chemical derivatization.

Binary Micellar Solutions of Poly(Ethylene Oxide)-Poly(Styrene Oxide) Copolymers with Pluronic® P123: Drug Solubilisation and Cytotoxicity Studies

The non-commercial copolymers E45S8, E45S17 and their mixtures with Pluronic® P123 (E21P67E21) were studied as carriers of the model drug griseofulvin. Critical micelle concentration (cmc) (dye solubilisation method), drug solubilisation capacity (Scp and Sh) determined by ultraviolet-visible (UV-Vis) spectroscopy and 1H nuclear magnetic resonance (1H NMR) and cytotoxicity (LDH activity in human neutrophils) were studied. E45S17 1.0 wt.% dispersions presented colloidal aggregates limiting its Scp in comparison to E45S8, but in 0.1 wt.% solutions this phenomenon seemed to be absent and E45S17 presented a higher Scp. The mixtures that showed the best Scp results contained 50% of P123 and presented low cmc. An evaluation of literature data suggested a minimum Em content of 62% in EmSn copolymers below which the increase of Sn length does not lead to an increase of Sh. The results suggested no toxicity of the copolymers on human neutrophils, supporting the use of P123 and poly(styrene oxide) containing copolymers as drug carriers.