Phytochemical study and insecticidal activity of Mentha pulegium L. oils from Morocco against Sitophilus Oryzae

Abstract

Abstract:There is a growing interest of industry to replace synthetic chemicals by natural products with bioactive properties from plant origin. The aim of this study was to validate the therapeutic properties of Mentha pulegium L. by conducting a phytochemical study, to determine the chemical composition of its essential oils (EO) and evaluate its insecticidal activity against stored cereals pests. Leaves and flowers of M. pulegium L.were collected from three regions of the Moroccan Middle Atlas. Phytochemical tests on pennyroyal aerial parts revealed the presence of gallic tannins, flavonoids, alkaloids, sterols and triterpenes and saponins. The chemical composition of essential oils was analyzed by gas chromatography coupled with mass spectrometry. The main components were pulegone and piperitenone. The EO from Khénifra is dominated by pulegone (81.46%), and those from Azrou and M'rirt are rich both in pulegone (68.86 and 71.97%) and piperitenone (24.79% and 26.04%) respectively. Pennyroyal oil has showed an important fumigant effect against Sitophilus oryzae (L.) adults. This effect is influenced by the tested doses and exposure periods. The potential of this plant to be used to control stored product insects was discussed.

Fumigant and repellent potentials of Ricinus communis and Mentha pulegium essential oils against Tribolium castaneum and Lasioderma serricorne

“…Moreover, pulegone can be used in many other fields such as food, cosmetic, and pharmaceutical industries where it is used as a traditional remedy, a flavouring, and a spice. [34,35] These results were in accordance with other studies already carried out in Algeria, India, and Uruguay where M. pulegium EOs were characterized by their high rates of pulegone with percentages of 46.41%, (65.9-83.1%), and 73.4% respectively. [36][37][38] Nevertheless, this composition was different from Mentha pulegium EOs in Morocco and Iran and was characterized by two specific chemotypes: that of piperitone (35.56 and 38%) and piperitenone (21.12 and 33%) where the rate of pulegone did not exceed 2.3 and 6.42%, respectively.…”

“…[36][37][38] Nevertheless, this composition was different from Mentha pulegium EOs in Morocco and Iran and was characterized by two specific chemotypes: that of piperitone (35.56 and 38%) and piperitenone (21.12 and 33%) where the rate of pulegone did not exceed 2.3 and 6.42%, respectively. [35] Other compounds were poorly represented such as neoisomenthol (4.03%) and p-menth-3-ene (1.29%) ( Table 1). The contribution of monoterpene hydrocarbons in pennyroyal EO did not exceed 2.08%.…”

Biocidal Compounds from Mentha sp. Essential Oils and Their Structure–Activity Relationships

“…littoralis , M . persicae among other insect species, toxicity, insect growth inhibition and related effects . Pulegone epoxide, carvone, carvone epoxide, piperitenone oxide, and piperitone have been reported as a strong antifeedants, toxic, and repellent against chewing and sucking insects …”

Insecticidal effect of Mentha pulegium L. and Mentha suaveolens Ehrh. hydrosols against a pest of citrus, Toxoptera aurantii (Aphididae)

“…Some constituents were found in hydrosol but absent in EO such as suaveolens EO was also piperitenone oxide but with a higher rate than hydrosol (74.69 %) followed by pulegone (2.34 %). Other compounds occurred in EO, but they were absent in hydrosol as limonene (1.85 %), b-pinene (0.65 %), cis-sabinene hydrate (0.53 %), and a-pinene (0.36 %) [27]. The M. suaveolens Ehrh.…”

“…Moreover, the M. suaveolens Ehrh. And M. pulegium L.(EOs), extracted from the same plants, have a broad insecticidal effect against S. oryzae adults but the M. suaveolens were also the most effective [26,27]. Similarly, Boughdad et al [38] have reported that the mortality of C. Maculatus adults, induced by M. Suaveolens (piperitenone 34 %) and pennyroyal (pulegone 65 %) EOs, reached 100 % after 3 and 6 days of exposition, respectively.…”