Essential oils rich in pulegone for insecticide purpose against legume bruchus species: Case of <i>Ziziphora hispanica</i> L. and <i>Mentha pulegium</i> L.

Ziziphora hispanica L. and Mentha pulegium L. are aromatic shrubs known to produce essential oils demanded by food industries. This study reports on the insecticidal activity of these two oils harvested in Khenifra (Morocco) and of its major compound (Pulegone) against the main legume bruchids. Chromatographic analysis revealed the presence of 33 compounds in the essential oil of Ziziphora hispanica (EOZH) and 24 compounds in the essential oil of Mentha pulegium (EOMP), with pulegone being the most dominant in both with percentages respectively of 79.1% and 63.8%. According to the insecticidal activities exerted, the two essential oils, as well as the pulegone, showed significant results against all the bruchids tested of legumes. Pulegone has shown good insecticidal activity, thus the lethal doses of 50% are between 61.6mg/g and 74.4mg/g, which explains the remarkable activity of the two essential oils which are rich in this molecule. moreover, the addition of essential oils in the storage of legumes does not have a significant effect on the legumes and does not diminish their nutritional qualities. This study indicates that essential oils and their main constituent have the potential to be developed into botanical insecticides

Phytochemistry and Biological Activities of Essential Oils from <i>Satureja calamintha</i> Nepeta

Satureja calamintha nepeta (S. calamintha) has a history of successful use in the treatment of bacterial and fungal diseases. The present study was designed to investigate the chemical composition and antioxidant and antimicrobial activities of essential oils extracted from wild S. calamintha (EOSS) and domesticated S. calamintha (EOSD) for comparison purposes. Hydrodistillation was used to extract the essential oils (EOs), while GC/MS was used for chemical analysis. Antioxidant activity was studied using DPPH and FRAP assays. Antifungal activity was performed against Candida albicans, Aspergillus niger, Aspergillus flavus, and Fusarium oxysporum), while antibacterial activity was tested against clinically resistant bacteria, namely Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Proteus mirabilis. By using ab=n in silico approach, the antioxidant and antimicrobial activities of the main compounds of EOSS and EOSD were also investigated. The yields obtained of EOSS and EOSD were 2.80% and 1.95%, respectively, with a dominance of eucalyptol, pulegone and rotundifolone. Concerning the antioxidant power, the IC50 values recorded by the use of the DPPH assay were in the range of 23.03 ± 4.30 and 24.09 ± 4.38 μg/mL for EOSS and EOSD, respectively, while by using the FRAP assay, the EC50 values were in the range of 55.38 ± 2.16 and 60.72 ± 7.71 μg/mL for EOSS and EOSD, respectively. Importantly, both essential oils of EOSS and EOSD exhibited good antibacterial activity against all studied bacteria; notably, the inhibition zone ranged from 14 ± 0.00 to 48.67 ± 1.15 mm and the MICs ranged from 0.37 ± 0.00 to 5.96 ± 0.00 µg/mL. Similarly, the studied EOs showed important antifungal activities compared to all the studied fungi, wherein the inhibition percentage ranged from 47.33 ± 1.15 to 89.18 ± 0.75%, while the MICs ranged from 0.18 ± 0.00 to 2.98 ± 0.00 µg/mL. The molecular docking results showed that piperitenone and pulegone strongly inhibited human acetylcholinesterase, whereas (+)-Isomenthone and piperitenone strongly inhibited S. aureus nucleoside diphosphate kinase, and E. coli beta-ketoacyl-[acyl carrier protein] synthase, respectively. The outcome of this article suggests that EOs of S. calamintha can be developed as alternative agents to manage drug-resistant phenomena and free radical issues