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

Correlation of the Diffusion Parameters and the Biological Activities in the Formulation of <i>Pinus halepensis</i> Essential Oil in Phosphogypsum Material

The use of natural biopesticides, specifically essential oils, is being explored as an alternative solution to protect stored foodstuffs. This study focuses on a formulation of phosphogypsum–Pinus halepensis essential oil as a pesticidal product. First, the essential oil chemical composition was determined using gas chromatography with mass spectrometry (GC-MS), while the phosphogypsum (waste from the phosphate mining industry) was analyzed using scanning electron microscopy, X-ray fluorescence, X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric–differential thermal analysis; thus, physico-chemical properties and heavy metal contents were determined. In a second step, the preparation of the formulation consists in grafting the essential oil on the phosphogypsum (adsorption) in a cylindrical geometric shape adapted to the models applied in the bioprocesses of storage. The study of essential oil transfers in the material in the case of desorption along the axis (Oz) was carried out using analytical and numerical models of the Fickian diffusion process to understand the behavior of the oil and determine physicochemical parameters such as diffusivity (D) and evaporation flux (F). By using statistical methods such as experimental design and principal component analysis, these parameters can help explain the mechanisms involved in the insecticidal activities against the primary pest of lentils (Bruchus signaticornis) and in the parameters of lentil seed germination