*2.1. Phytochemical Screening*

Phytochemical screening indicated the presence of secondary metabolites families in *Origanum compactum* aerial parts: alkaloids, catechic tannins, sterols and triterpenes, flavonoids, saponosides, leucoanthocyanins, oses and holosides, and mucilages. On the other hand, gallic tannins and reducing compounds were almost absent.

Gallic acids, tannins, anthocyanes and flavonoids were previously reported as constituents of *Origanum compactum* [6]. Other species belonging to the same genus, e.g., *Origanum vulgare*, have also been proven to contain tannins, mucilages, proteins, alkaloids, steroids, flavanoids, starch and anthraquinones [7].

#### *2.2. Polyphenols Extractions Yield*

The extraction yield obtained using hydroethanolic solvent at 70% for *Origanum compactum* was 30.60%. A similar yield of polyphenol extraction by methanol from *Origanum compactum* was obtained by Zeroual et al. (31.70%), while the lowest yield (10.30%) was obtained for n-hexane extraction [3]. It has been reported that ethanol and methanol present similar yields in most cases [8].

The yield of extraction depends on the solvent used. A solvent's effectiveness is mostly determined by its capacity to dissolve particular phenolic groups [8]. Ethanol is one of the solvents that have been used for the extraction of polyphenols from different plants, whether as an aqueous mixture or as absolute ethanol [9], as it provides better results, being also safer for human health [10].
