Salvador Cañigueral

Antifungal activity of Paraguayan plants used in traditional medicine

The antifungal activity of aqueous, dichloromethane and methanol extracts from 14 Paraguayan plants used in traditional medicine for the treatment of skin diseases was assayed in vitro by the agar disk diffusion method against 11 fungal strains comprising several filamentous fungi and yeasts. Among them, the dichloromethane extracts of Acanthospermum australe, Calycophyllum multiflorum, Geophila repens and Tabebuia avellanedae, as well as the aqueous and methanol extracts of the latter, showed the highest activity.

Activity of artichoke leaf extract on reactive oxygen species in human leukocytes.

Artichoke leaf extract was studied in human leukocytes for activity against oxidative stress using flow cytometry and dichlorofluorescin diacetate as a fluorescence probe. It produces a concentration-dependent inhibition of oxidative stress when cells are stimulated with agents that generate reactive oxygen species (ROS): hydrogen peroxide, phorbol-12-myristate-13-acetate (PMA), and N-formyl-methionyl-leucyl-phenylalanine (FMLP). Cynarin, caffeic acid, chlorogenic acid, and luteolin, constituents of artichoke leaf extract, also show a concentration-dependent inhibitory activity in the above models, contributing to the antioxidant activity of the extract in human neutrophils.

Essential oils of Mentha pulegium and Mentha rotundifolia from Uruguay

Essential oils obtained by hydrodistillation from leaves of Mentha pulegium L. and Mentha rotundifolia (L.) Huds. from Uruguay were analysed by GC-FID and GC-MS. Oxygen-containing monoterpenes were the main group of constituents in both oils. Pulegone, isomenthone and menthone were the major components in the oil of M. pulegium, whereas piperitenone oxide and (Z)-sabinene hydrate were the major ones in M. rotundifolia. Enantiomerically pure (-)-menthone, (+)-isomenthone, (+)-isomenthol, (-)-menthol and (+)-pulegone were detected by multidimensional gas chromatography in the case of M. pulegium oil.

Essential oils from four piper species

Abstract The essential oils from Piper capense , P. nigrum , P. guineense and P. umbellatum from S. Tome e Principe were investigated for the first time. They were analysed by GC, GC-mass spectrometry and 13 C NMR. Monoterpene hydrocarbons were the main group of constituents in three of the samples ( P. capense, P. nigrum and P. umbellatum ), whereas for the other species ( P. guineense ) phenylpropanoid derivatives were the most important ones. β -Pinene (32.5%) and β -caryophyllene (12.6%) were the major compounds in the volatile oil of P. capense . Dillapiole (44.8%), followed by myristicin (9.8%), were the main constituents of P. guineense . The most important constituents in the essential oil of P. nigrum were limonene (18.8%), β -caryophyllene (15.4%), sabinene (16.5%) and β -pinene (10.7%). The essential oil of P. umbellatum was characterised by its high β -pinene (26.8%), α -pinene (17.6%) and (E)-nerolidol (12.4%) content.

Screening for antifungal activity of nineteen Latin American plants

Dichloromethane and methanol extracts of 19 Latin American plants, most of them selected on the basis of traditional medicine reports, were subjected to screening for antifungal activity, using the agar disk diffusion assay against several fungi. Of the extracts tested, those of Andira inermis, Andira surinamensis, Bixa orellana, Blepharocalyx tweediei, Croton zehtneri, Gallesia integrifolia, Hedyosmum anisodorum, Heterotheca inuloides, Hura crepitans, Mansoa alliacea, Ocimum micranthum, Persea laevigata, Piper elongatum, Piper fulvescens, Polygonum hydropiperoides and Potalia amara exhibited some level of activity.

Chemical polymorphism of the essential oil of Thymus carnosus from portugal

Abstract The composition of the essential oils of 11 populations of Thymus carnosus from Portugal and their infraspecific variability were investigated by GC, GC-MS and 13CNMR. The results obtained were submitted to Principal Component and Chemometric Cluster Analyses. Borneol was the main constituent in all the populations except in one, which had a high content of linalool. This compound showed high percentages in samples originating from the region of Estremadura. Multivariate analysis allowed the distinction between three different groups of essential oils, (i) borneol/cis-sabinene hydrate/terpinen-4-ol, (ii) linalool/borneol/trans-sabinene hydrate and (iii) borneol/camphene.

Composition and biological activity of the essential oil from leaves of Plinia cerrocampanensis, a new source of α-bisabolol.

The essential oil from fresh leaves of Plinia cerrocampanensis Barrie (Myrtaceae), obtained by hydrodistillation, was analysed by GC-FID and GC-MS. Forty components, representing more than 91% of the oil, were identified. Oxygenated sesquiterpenes represented the main fraction with alpha-bisabolol (42.8%) as the major constituent, making this plant a new and good source of this substance. Biological activity of the essential oil was evaluated against several bacterial and fungal strains as well as larvae from Aedes aegypti. The highest activity was found against Staphylococcus aureus, Pseudomonas aeruginosa, Microsporum gypseum, Trichophyton mentagrophytes and Trichophyton rubrum with MIC values from 32 to 125 microg/ml. The essential oil also showed potent inhibitory and bactericidal activities against three H. pylori strains, with MIC and MBC values of 62.5 microg/ml, and caused 100% mortality of A. aegypti larvae at a concentration of 500 microg/ml.

Variability of essential oils of Thymus caespititius from portugal

Abstract The composition and variability of the essential oils of several populations of Thymus caespititius from Portugal were investigated by GC, GC-mass spectrometry and 13 C NMR. All samples from NW Portugal were characterized by their high α-terpineol content, while the main components in the oil sample from Pico island (Azores archipelago) were carvacrol and thymol. The analytical data of individual samples from NW Portugal showed no chemical polymorphism in this area. The different areas of distribution (NW Portugal and Azores) that show great climatic and soil variation conditions may be the origin of the α-terpineol-type oil from NW Portugal and the carvacrol/thymol-type oil from the Azores. 13 C NMR spectra of the essential oil, previously fractionated by column chromatography, led to the identification of trans -dihydroagarofuran, a new oxygenated sesquiterpene for the genus Thymus and a characteristic compound of T.caespitiuius .

Essential oil composition of four Turkish species of Sideritis

The composition of the essential oils of four species of Sideritis, three of them endemic to Turkey, was investigated by GC and GC-mass spectrometry. They were characterized by the presence of a high percentage of monoterpene hydrocarbons. α- and β-pinene were the main constituents of S. congesta and S. argyrea, while limonene was the major one of the oil of S. perfoliata. S. condensata provided an essential oil with high proportions of β-caryophyllene and α-pinene.

Essential Oil Composition of Eryngium foetidum from S. Tomé e Príncipe

Abstract The essential oil of Eryngium foetidum leaves from S. Tomé e Príncipe was investigated for the first time. The oils were obtained by hydrodistillation of the leaves, from two different sites, and subsequently analyzed by GC, GC/MS and 13C-NMR. The oils were characterized by the presence of small amounts of monoterpene hydrocarbons and sesquiterpenoids, and by a large number of aromatic and linear aldehydes in high proportions, with 2,3,6-trimethylbenzaldehyde (5.5–23.7%), (E)-2-dodecenal (15.9–37.5%) and (E)-2-tetradecenal (18.7–25.3%) being the most dominant.