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Secondary plant metabolites, in particular phenolic compounds, are characterized by great diversity in the plant kingdom and are widely used in the medical and industrial fields. The extraction of these compounds represents a critical step, and the differences in extraction conditions strongly affect the yields and the total concentrations of polyphenols in the extracts. In this way, the objective of the present study was to optimize the extraction parameters of the polyphenols from Lavandula stoechas using the extraction technique assisted by ultrasound. Yield and the total concentration of polyphenols have been optimized, taking into account three variables, the extraction time (min), the ethanol concentration (%), and the solvent/extract ratio (ml/g). The optimum extraction yield (31.88%) was obtained by ensuring the following parameters: an ethanol concentration of 40%, a liquid/solid ratio of 30 ml/g, and a time processing of 32.62 min. The maximum concentration of total polyphenols (190.14 mg gallic acid equivalents (GAE)/g) was obtained after 21.5 min of extraction, with a liquid/solid ratio of 30 ml/g and a concentration of ethanol at 40%. In order to obtain the maximum yield (24.9%) and the total concentration of polyphenols (190.14 mg GAE/g) simultaneously, the following parameters must be adjusted: an extraction time of 21.5 min, a liquid/solid ratio of 30 ml/g, and a concentration of ethanol at 40%. The experimental values of the yield and the total concentration of the polyphenols were in good agreement with the predicted values, which suggests that the ultrasonic extraction model adopted in this study is validated.

Background. Withania frutescens. L (W. frutescens) is a perennial woody medicinal plant belonging to family Solanaceae largely used by the indigenous population to Morocco for the treatment of disease. Objective. The purpose of this study was to investigate the chemical composition, acute, and subacute toxicity of W. frutescens extract in mice. Materials and Methods. The phytochemical composition of W. frutescens extract was determined using a gas chromatograph (GC/MS). Acute toxicity study was carried out in mice through oral administration of single doses 500 mg/kg, 1000 mg/kg, and 2000 mg/kg for 14 days. Subacute toxicity was performed with oral administration of repeated doses 500 and 2000 mg/kg/day for 28 days. Biochemical parameters (alanine aminotransferase, aspartate aminotransferase, urea, and creatinine), as well as histopathological changes potentially occurred in organs, (liver, kidney, and spleen) were evaluated. Results. The results of chromatographic analysis showed the richness of W. frutescens extract in interesting phytochemical compounds majorly constituted of bicyclo[3.1.1]heptane, 6,6-dimethyl-2-methylene-(C10H16). Regarding acute toxicity study, the results showed no clinical symptoms occurred in treated mice compared to the control group and no histological changes detected in analyzed organs of treated mice with dose put to 2000 mg/kg nor adverse effect on biochemical parameters. Conclusion. The outcome of this work showed no toxic effect of W. frutescens in mice up to dose 2000 mg/kg bodyweight. Therefore, this study could scientifically validate further traditional use with safety in the range of tested doses.

The aim of this study is to investigate in vitro antioxidant and antibacterial activities of the aqueous and hydroethanolic extracts for aerial parts of Herniaria hirsuta. Extracts were screened for their possible antioxidant activities by three tests: DPPH free radical-scavenging, reducing power, and molybdenum systems. The screening of antibacterial activity of extracts was individually evaluated against sixteen bacteria species using a disc diffusion method. Flavonoids, total phenols, and tannins content were performed for both extracts. It shows higher content in the hydroethanolic extract. The hydroethanolic extract showed a significant antioxidant activity for the three methods studies to the aqueous extract, but nonsignificant results compared to the reference (BHT). However, both extracts have negative effect on the strains studies for the antibacterial activity.