Biological and Nonbiological Antioxidant Activity of Some Essential Oils.

Fifteen essential oils, four essential oil fractions, and three pure compounds (thymol, carvacrol, and eugenol), characterized by gas chromatography and gas chromatography-mass spectrometry, were investigated for biological and nonbiological antioxidant activity. Clove oil and eugenol showed strong DPPH (2,2-diphenyl-1-picrylhydrazyl) free-radical scavenging activity (IC50 = 13.2 μg/mL and 11.

Antioxidant and Hepatoprotective Activity of a New Tablets Formulation from Tamarindus indica L.

Hepatotoxic chemicals damage liver cells primarily by producing reactive oxygen species. The decoction of the leaves of Tamarindus indica L. is used for liver disorders.

Effect of some essential oils on phagocytosis and complement system activity.

The aim of the present study was to investigate the in vitro activity of 15 essential oils, 4 essential oil fractions, and 3 pure compounds (thymol, carvacrol, and eugenol) on phagocytosis by human neutrophils and on complement system. Samples were characterized by GC and GC-MS. Most of the oils (nutmeg, clove, niaouli, tea tree, bay laurel, lemon, red thyme, ginger), nutmeg terpenes, eugenol, and carvacrol showed mild to moderate inhibition of phagocytosis (25-40% inhibition at doses ranging from 40 to 60 μg/mL); highest inhibitory activity was found for thymol (72% at 56 μg/mL), whereas the mixture of bornyl and isobornyl acetates showed a mild stimulating activity (21% at 56 μg/mL).

Antioxidant activity of Tween-20 and Tween-80 evaluated through different in-vitro tests.

Objectives: This study aimed to evaluate the possible antioxidant activity of Tween-20 and Tween-80, two amphipathic nonionic surfactants commonly used as solubilizers and stabilizers, whose pharmacological effects have been ignored to a large degree.

Methods: Antioxidant activity was investigated in vitro measuring the scavenging activity on the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH(●) ), the production of reactive oxygen species (ROS) in activated human neutrophils using flow cytometry and the myeloperoxidase (MPO) inhibitory activity.

Key Findings: Tween-20 and Tween-80 did not show scavenging activity on DPPH(●) , while produced a decrease of the ROS production in human neutrophils, being Tween-20 more active than Tween-80.

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

Quantitative study of the structure-retention index relationship in the imine family.

The Kováts retention index is one of the most popular descriptors of the performance of organic compounds in gas chromatography (GC). The mathematical modeling of this index is an interesting and open problem in analytical chemistry. In this paper, two models for the prediction of the Kováts retention index are presented.