*2.7.2 Total phenolic content*

Estimation of the total phenol content was determined by the Folin–Ciocalteu calorimetric method [38] where gallic acid was used as the standard. Therefore, it was measured as gallic acid equivalent (GAE) and expressed as g of GAE/L of OMW.

## *2.7.3 OMW phenolic compounds identification*

HPLC analysis was conducted at the Center for Analysis and Characterization (Cadi Ayyad University, Marrakesh, Morocco) with C18 column (Eurospher II 100–5, 250 x 4.6 mm) in gradient system (eluting solution A = acetonitrile; eluting solution B = *o*-phosphoric acid/water (pH = 2.6), 5/95 v/v). A volume of 10 μl was injected at a flow rate of 1 mL/min and pressure of 117 bar. The characterization of phenolic compounds was carried out using their UV–Vis diode-array detector at a spectrum of 280 nm and their identification was performed by comparing their retention time (RT) with standards. Then these compounds were quantified through the calibration curve of the corresponding standards. The results obtained were expressed in g/L.

#### **2.8 Larvae cultures**

Sampling of larvae of *P. opaca* var. cardui Gyllenhal (**Figure 3**) was conducted according to section sampling techniques. The larvae were reared in round boxes (8 cm x 5 cm: diameter x height) containing a mixture of palm waste (150 g). The larvae culture was maintained in darkness at an optimal temperature between 25 and 30°C inside an incubator. The experiments were conducted in the same conditions as those for the cultures.
