Rosmarinus officinalis L. is a dietary source that produces polyphenols as secondary metabolites. These natural compounds with potent antioxidant abilities are increasingly recommended as a supplement to inhibit oxidative stress. In the current work, we evaluated the impact of the extraction method on the chemical composition of R. officinalis extract, especially on the content of carnosic (CA) and rosmarinic (RA) acids using UPLC-MS-DAD as well as on their antioxidant potency. Four extracts of Tunisian rosemary were obtained from non-conventional extraction techniques:ultrasound-assisted extraction (UAE),supercritical extraction (SFE) and UAE and SFE combined ((UAE-SFE(I), UAE-SFE(II)). The UAE exhibited the best total phenolic compounds (i.e., 85.27 mg GAEg⁻¹), the highest content of CAand RA and the strongest antioxidant abilities (i.e., IC₅₀ = 0.13 mg/mL and EC₅₀ = 0.93 mg/mL for DPPH scavenging test and iron reducing power ability assay). The evaluation of antioxidant activity of UAE inhuman skin fibroblast (HS-68) cell line was carried out after the induction of oxidative stress. The results determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed a strong protective effect against H₂O₂oxidative stress induction in cells pretreated with UAE. The obtained results allow us to give new insight about the effect of the extraction method on the chemical composition and biological activities of the extract and the importance of the choice of the most appropriate processing technique to prepare rosemary extract with a high antioxidant potency and protective effect against oxidative stress.

Large quantities of plant waste are rejected daily in our universe. Consequently, several researchers have proposed various ways to enhance them. One of these possible routes is recovery as a natural dye for textile use. This study aims to explore the possibility of recovering the Juglans Regia. L barks residues in natural dyeing. Hence, the extraction of a bio-dye was carried out by microwave, several parameters were studied, namely: the microwave power, the pH, and the duration. The total phenolic compounds, flavonoids, condensed and hydrolyzable tannins contents were estimated each time. Then, the colored extracts were used for dyeing wool fabrics. The Dyeing quality resulted was estimated by calculating the colorimetric coordinates (L*, a*, b*) and the color strength (K/S). Good results were obtained, with brown shades and a color strength (K/S) close to 15 was reached. The dyeing fastnesses were also checked, acceptable fastnesses to washing, rubbing and to light were obtained. Finally, the dyed and undyed wool samples were characterized by spectral Infrared analysis and a proposal of possible dyeing mechanisms was suggested.