The purpose of this study is to determine the total content of phenols, flavonoids, and condensed tannins, as well as on the antioxidant activity of the extract, and their fractions were measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), phosphomolybdate reduction (or total antioxidant capacity), and cyclic voltammetry (CV). The hydromethanolic extract of Salvia officinalis showed the highest values of total phenolic (176 mgGAE/g of extract) and condensed tannins (162.53 mgEC/g of extract) from the Boulemane and Khenifra regions, respectively. The results showed that the best DPPH assay was found in the ethyl acetate fraction of Salvia officinalis leaves of the Boulemane region (IC50 = 0.002 mg/ml). For the ethyl acetate and butanolic fractions of Salvia officinalis leaves, those collected from different regions have a better reducing capacity (EC50 = 0.021 mg/ml, respectively). For the total antioxidant capacity, the best activity was found in the aqueous fraction of Salvia officinalis leaves of the Boulemane region (108 mgGAE/g of extract). By the cyclic voltammetry method, hydromethanolic extract of Salvia officinalis leaves from the Boulemane region showed an important result (288.8 mgGAE/g). There was a positive correlation between total phenol content (TPC), condensed tannin content (TCT), and total antioxidant capacity (TAC) (r = 0.932, r = 0.896, respectively). The main compounds that have been identified in the hydromethanolic extract of Salvia officinalis are ascorbic acid, gallic acid, 4-hydroxybenzoic acid, tannic acid, and rutin. Due to their antioxidant property, the leaf extracts from Salvia officinalis are used as natural preservative ingredients in food and/or pharmaceutical industries.

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A novel Microwave‐Assisted Soxhlet Extraction (MASE) was performed to upgrade the classic Soxhlet extraction of polyphenols from pomegranate peels, one of the most studied by‐products. The response surface methodology (RSM) modeling was used for the estimation of predictive total polyphenols content (TPC), total flavonoid content (TFC), and total tannin content (TTC). Maximum compounds of the three output parameters: 376 mg gallic acid equivalents (GAE)/g dry weight (dw) TPC yield, 163 mg rutin equivalents/g dw TFC yield, and 323 mg GAE/g dw TTC yield, were obtained under optimum extraction conditions. In addition, the extract had a high antioxidant capacity of 533g ascorbic acid equivalent/g dw using 2,2‐diphenyl‐1‐picrylhydrazyl assay. The major phenolic compounds, especially punicalagin, were identified by ultra‐high‐performance liquid chromatography followed by the electrospray ionization coupled with mass spectrometry (UHPLC/ESI/MS). The proposed method (MASE) permitted to develop a fast solvent‐minimized extraction process and improve the quantity of extracts obtained from a natural resource. Practical applications The valorization of natural by‐products involves the optimization and improvement of extraction techniques. MASE is a coupling of two conventional extractions that could be used in industry to improve yields, while reducing the time and cost of extracting target bioactive compounds. With this coupling, it is possible to modify or add other factors to target a well‐defined molecule in order to obtain the richest extract in these target molecules.

The aim of this work is to evaluate the antioxidant effects of the extracts of Pistacia atlantica collected in the Khenifra region (Morocco) in 2016. Different methods were used to study these extract: 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, the ferric reducing ability of plasma (FRAP) assay, the phosphomolybdate method for determining the total antioxidant capacity, and the electrochemical method for cyclic voltammetry were employed to evaluate the antioxidant capacity of Pistacia atlantica Desf. Phytochemical screening helped us to highlight the presence of secondary metabolites. The extraction of the phenolic compounds was carried out by the Soxhlet method in the presence of different mixtures solvents (ethanol/water and methanol/water); the fractions of the different extracts were affected using ethyl acetate and n-butanol. The dosage results showed that the ethanolic extract was rich in total phenols (260.4 mg GAE/g of the extract) and in total flavonoids (129.15 mg QE/g of the extract), while the butanolic fraction was rich in condensed tannin (50.96 mg CE/g of the extract). The qualitative analysis was performed by high performance liquid chromatography (HPLC). The main compounds that were identified in the methanolic and ethanolic extracts of Pistacia atlantica Desf were ascorbic acid, gallic acid, tannic acid, rutin, and quercetin. The results of the antioxidant activity revealed that the butanolic and ethyl acetate fractions exhibit a good iron reduction capacity (concentration that gave half maximal response, EC50 = 0.02 mg/ml and 0.03 mg/ml, respectively) and a very interesting antiradical activity with an IC50 (concentration of inhibitor where the response is reduced by half) = 0.08 mg/ml and 0.04 mg/ml, respectively. Cyclic voltammetry presented a single oxidation peak between 400 and 500 mV. The ethanolic and methanolic extracts were recorded from the oxidation currents values of 15.75 and 10.41 i/μA cm.2 respectively at the concentration 0.1 mg/ml. Hence, it is clear that the leaves of Pistacia atlantica Desf, which are currently often considered as potential antioxidants, contain antioxidants that can usefully be extracted and added to foods.