Background:The Gracilaria bursa-pastoris is an abundant alga that is responsible for the eutrophication in Nador lagoon in Morocco. Therefore, the lagoon is a deposit of bioresources whose economic value can be enhanced. Antioxidative properties of seaweed extracts have been studied in several geographic regions, but only a few studies have been performed on tropical seaweed species, and no research has been done to determine antioxidant activity and valorization of the indigenous algae in Nador lagoon in Morocco. Methods:The present study evaluated the antioxidant potential of methanolic and aqueous extracts from Gracilaria bursa-pastoris by measuring the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and total content of phenolic, flavonoids and flavonols content in each extract.Results: This study showed that this macroalgae contained a high total phenolic content (142.26 and 79.43 mg GAE g−1 extract) for ethanolic and aqueous extracts, respectively. All extracts exhibited a DPPH radical scavenging activity, and the methanolic extracts demonstrated a great antioxidant potential with very low value of EC50 (0.085 mg/mL), significantly equivalent to EC50 (0,028 mg/mL) of commercial antioxidant ascorbic acid. These results suggest that the macroalgae have a great antioxidant potential which could be considered for future applications in medicine, food production or cosmetic industry in Morocco. Conclusions:This work showed that the ethanolic extract was rich in phenolic compounds. This extract exhibited the highest antioxidant activity which may be explained by the presence of a large quantity of phenolic compounds. The Gracilaria bursa-pastoris can be utilized as a source of natural antioxidant compounds.

The focus of this study is the physicochemical and bacteriological characteristics of groundwater in the Triffa plain, Morocco. In total, 34 groundwater samples were analyzed for major elements (Tp, pH -) and trace metal (Al, Cd, Cu, Fe, and Zn) content. The results show that the pH values range between 6.7 and 8.9, electrical conductivity ranges between 740 and 7340 lS/cm, and nitrate content ranges between 1.7 and 212 mg/l. Hydrochemical facies represented using a Piper diagram indicate an Na-K-Cl type water. All the trace metal concentrations are within the admissible standard range except for Cd. The bacteriological analysis showed that the majority of groundwater samples are contaminated. Generally, the content of total coliforms, fecal coliforms, and fecal streptococci ranged from 0 to 140, 0 to 125, and 0 to 108 CFU/100 ml, respectively. The samples are grouped according to three factors. Factor 1 shows strong positive loadings of EC, Mg, Cl, Na and K with 51.91% of total variance (TV); factor 2 shows strong negative loadings of NO 3 , SO 4 and Ca with 17.98% of TV; and factor 3 shows strong negative loading of HCO 3 with 15.56 of TV. We conclude that the quality of this groundwater is suitable for irrigation and domestic use (cleaning house, ect).

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