linoleic-acid and beta-pinene

Chemical composition, antioxidant and antimicrobial activities of the fresh leaves and stems oils of Piper caninum were investigated. A total of forty eight constituents were identified in the leaves (77.9%) and stems (87.0%) oil which were characterized by high proportions of phenylpropanoid, safrole with 17.1% for leaves and 25.5% for stems oil. Antioxidant activities were evaluated by using β-carotene/linoleic acid bleaching, DPPH radical scavenging and total phenolic content. Stems oil showed the highest inhibitory activity towards lipid peroxidation (114.9 ± 0.9%), compared to BHT (95.5 ± 0.5%), while leaves oil showed significant total phenolic content (27.4 ± 0.5 mg GA/g) equivalent to gallic acid. However, the essential oils showed weak activity towards DPPH free-radical scavenging. Evaluation of antimicrobial activity revealed that both oils exhibited strong activity against all bacteria strains with MIC values in the range 62.5 to 250 μg/mL, but weak activity against fungal strains. These findings suggest that the essential oils can be used as antioxidant and antimicrobial agents for therapeutic, nutraceutical industries and food manufactures.

Topics: Anti-Infective Agents; Antioxidants; beta Carotene; Bicyclic Monoterpenes; Bridged Bicyclo Compounds; Gas Chromatography-Mass Spectrometry; Linoleic Acid; Lipid Peroxidation; Microbial Sensitivity Tests; Monoterpenes; Oils, Volatile; Phenols; Piper; Plant Extracts; Plant Leaves; Plant Stems; Polycyclic Sesquiterpenes; Safrole; Sesquiterpenes; Sesquiterpenes, Germacrane

The genus Citrus has a number of species and hybrids that are well established for their pharmaceutical and economic importance. The essential oil from Citrus karna Raf (Rutaceae) was analyzed for D-limonene (92.31%), the major chemical constituent, along with other minor constituents such as alpha-pinene (1.23%) and beta-pinene (1.80%). It showed significant inhibition for the oxidation of linoleic acid in the beta-carotene-linoleic acid system. Essential oils A and B obtained from C. sinensis, with 35.08% and 76.68% d-limonene, respectively, were used to evaluate the effect of the d-limonene concentration on antioxidant potential. Studies showed that d-limonene and C. karna essential oil have a similar antioxidant potential (39.6 and 38.3%, respectively). C. sinensis oils A and B showed only 10.5% and 30% antioxidant potential, respectively, indicating the possible role of d-limonene in antioxidant activity.

Topics: Antioxidants; beta Carotene; Bicyclic Monoterpenes; Bridged Bicyclo Compounds; Citrus; Cyclohexenes; Gas Chromatography-Mass Spectrometry; Limonene; Linoleic Acid; Monoterpenes; Oils, Volatile; Oxidation-Reduction; Terpenes