Products of natural origin remain important in the discovery of new bioactive molecules and are less damaging to the environment. Benzaldehyde is a product of the metabolism of plants, and similarly to oxygenated terpenes, it can have antibacterial activity against Staphylococcus aureus and toxic action against Drosophila melanogaster; we aimed to verify these activities. The broth microdilution tests determined the minimum inhibitory concentration (MIC) of benzaldehyde alone and in association with antibiotics and ethidium bromide (EtBr). Toxicity against Drosophila melanogaster was determined by fumigation tests that measured lethality and damage to the locomotor system. The results indicated that there was an association of norfloxacin and ciprofloxacin with benzaldehyde, from 64 μg/mL to 32 μg/mL of ciprofloxacin in the strain K6028 and from 256 μg/mL to 128 μg/mL of norfloxacin in the strain 1199B; however, the associations were not able to interfere with the functioning of the tested efflux pumps. In addition, benzaldehyde had a toxic effect on flies. Thus, the results proved the ability of benzaldehyde to modulate quinolone antibiotics and its toxic effects on fruit flies, thus enabling further studies in this area.
The Aedes aegypti is responsible for the transmission of arboviruses, which compromise public health. In the search for synthetic product alternatives, essential oils (OEs) have been highlighted by many researchers as natural insecticides. This systematic review (SR) was performed according to PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and its objective was to evaluate studies addressing OEs with larvicidal properties against Ae. aegypti, through electronic database searches (Pubmed, Science Direct and Scielo), covering an overview of the plant sources OEs, which plant parts were used, the extraction methods, analytical techniques, major and/or secondary constituents with greater percentages, as well as the LC50s responsible for larval mortality. Following study analysis, plants distributed across 32 families, 90 genera and 175 species were identified. The Lamiaceae, Myrtaceae, Piperaceae, Asteraceae, Rutaceae, Euphorbiaceae and Lauraceae families obtained the highest number of species with toxic properties against larvae from this vector. Practically all plant parts were found to be used for OE extraction. Hydrodistillation and steam distillation were the main extraction methods identified, with GC-MS/GC-FID representing the main analytical techniques used to reveal their chemical composition, especially of terpene compounds. In this context, OEs are promising alternatives for the investigation of natural, ecologically correct and biodegradable insecticides with the potential to be used in Ae. aegypti control programs.
1 February 2017 in Saudi Journal of Biological Sciences
Evaluations of the therapeutic potential of medicinal plants and their components have been the subject of many studies. Furthermore, the biological activities of various plant species have been reported in various pieces of literature. Hyptis martiusii Benth (Lamiaceae), popularly known as "mad balm" is commonly found in the North, Southeast, and Northeast of Brazil. Its leaves are used ethnobiologically as antiulcerogenic, antimicrobial, antitumor and as insecticide. This study aimed to analyze the chemical composition of the essential oil of H. martiusii Benth (OEHM) by GC/MS as well as its possible topical activity as an antiedematogenic. This is verified by the models of ear edema induced by single (acute edema) and multiple (chronic edema) applications of croton oil topically, and systemically verified through the model of paw edema induced by carrageenan 1%. Doses of 50, 75 and 100 mg/kg OEHM were used in all tests. Chemical analysis of the oil revealed the 1,8-cineole (34.58%) and δ-carene (21:58%) as major components present in the essential oil. On the model of ear edema, acute and chronic OEHM in all the tested doses showed no significant antiedematogenic activity (p < 0.05). The systemic model of paw edema induced by carrageenin showed that a dose of 100 mg/kg effectively reduced swelling by 55.37% in the second hour evaluation when compared to the saline group. The anti-inflammatory systemic effect can give greater bioavailability of the components present in the essential oil and your interference in cytokines and leukotriene, thromboxane and prostaglandin biosynthesis. It is therefore concluded that OEHM presents systemic antiedematogenic activity but not topical activity at these doses.