RESUMO
The present work was aimed to study the toxicity of the essential oils of three aromatic and medicinal plants on the tomato leaf miner Tuta absoluta and the Medfly Ceratitis capitata as an alternative to conventional pesticides. We carried out a phytochemical and insecticide study of T. zygis L., S. officinalis L. and M. suaveolens Ehrh. essential oils (EOs) through the study of their chemical composition and their toxicity on C. capitata adults and T. absoluta larvae. The extraction of the EOs by hydrodistillation showed yields of 3.87 ± 0.03, 4.09 ± 0.23 and 4.35 ± 0.11 for T. zygis, S. officinalis L. and M. suaveolens Ehrh., respectively. The identification of the chemical composition of the EOs by GC/MS showed that oxygenated monoterpenes constituted the most abundant group for all the extracted EOs. The major compounds were rather diversified depending on plant species. In fact, the S. officinalis L. EO mainly contained trans-thujone (21.80 %), the M. suaveolens Ehrh. EO mainly contained piperitenone oxide (71.19%), and carvacrol (61.60%) was the main component of the T. zygis L. EO. An insecticidal effect was observed for the three studied EOs on C. capitata adults and T. absoluta larvae. The observed LD50 values were 0.80 µL/mL and 11.04 µL/mL for M. suaveolens and S. officinalis, respectively, on T. absoluta larvae. For C. capitata adults, the obtained LD50 values were 0.9 µL/mL and 11.78 µL/mL for M. suaveolens and T. zygis, respectively. The presented findings could contribute to the development of biopesticides for plants as a component of integrated pest management strategies in citrus and tomato crops.
RESUMO
Anacyclus pyrethrum (L.) (Asteraceae) is an important annual medicinal herb and is widespread in Morocco and Algeria. Most of its parts are used in traditional medicine and the roots are the most important parts used. The present review gives an account of the updated information on its phytochemical and pharmacological properties. We have collected the essential characteristics and the different scientific data of the A. pyrethrum species, and reviewed its potential. It is seen from the literature that A. pyrethrum is a rich source of the phytochemical constituents such as alkaloids (pellitorin) and n-alkylamides. This species also contains pyrethrins, sesamin, traces of essential oils and a wide range of other chemical compounds. These active substances possess antimicrobial and anti-inflammatory activities. The plant has an antidiabetic, insecticidal and immunostimulatory effect, as well as an aphrodisiac and antioxidant potentials, and various other important medicinal properties. Many traditional uses are also reported in previous research such as for rheumatism, sciatica, colds, neuralgia and paralysis. This species is considered to be a sialagogue, and used in the treatment of stomach ailments, diseases of inflammation of the mouth, against cysts in the genital tract and to relieve toothaches. Thus, further research must be carried out in order to establish any relationship between the traditional uses, phytochemistry and toxicity. Moreover, A. pyrethrum is quite promising as a medicinal agent, so further clinical trials should be performed to prove its efficacy.
RESUMO
Thymus capitatus and Thymus broussonnetii are two Moroccan endemic medicinal plants used traditionally by the local population. The present study aims to investigate their essential oil chemical composition, antioxidant and antibacterial activities. The chemical composition of the essential oils was determined using the GC-MS analysis, the antioxidant activity assessed using DPPH and FRAP methods while the antimicrobial activity was evaluated against nine bacteria species tested (Enterococcus faecalis, Serratia fonticola, Acinetobacter baumannii, Klebsiella oxytoca, sensitive Klebsiella pneumoniae, sensitive Escherichia coli, resistant Escherichia coli, resistant Staphylococcus aureus and Enterobacter aerogenes). The major identified compounds of T. capitatus essential oil where carvacrol (75%) and p-cymene (10.58%) while carvacrol (60.79%), thymol (12.9%), p-cymene (6.21%) and γ-terpinene (4.47%) are the main compounds in T. broussonnetii essential oil. The bioactivity of the essential oils of the two species of thyme was explained by their richness in oxygenated monoterpenes known for their great effectiveness with an IC50 of 3.48 ± 0.05 and 4.88 ± 0.04 µL/mL and EC50 of 0.12 ± 0.01 and 0.20 ± 0.02 µL/mL in the DPPH and FRAP assays, respectively, with an important antibacterial activity. These results encourage the use of these plants as a source of natural antioxidants, and antibacterial additives, to protect food from oxidative damage and to eliminate bacteria that are responsible for nosocomial infections.