A green approach for the sustainable and effective valorization from Populus nigra buds as a renewable source of high value-added extract using an alternative solvent with prospective application in skin care formulation

Abstract

Many studies have been conducted on the biological potential of medicinal plant extracts; the present study looked into the use of antioxidant extracts from P.nigra buds in cosmetic formulations to boost photoprotection potential, with a particular emphasis on green extraction and the biological activities of these compounds. Extraction of phenolic compounds using ultrasonically assisted lactic acid reported content of 42.64 ± 0.16 mg GAE/g dw with an antioxidant potential of 72.20 ± 1.05 mmol TE/100g dw and 72.73 ± 2.59 mg AAE/g dw for DPPH• and OH• scavenging activities, respectively. Furthermore, a significant iron chelation capacity of the extract was recorded (104.45 ± 1.66 mg EDTA E/g dw). In addition, a strong anti-inflammatory activity of the extract was demonstrated (IC50 : 0.122 and 0.1788%) for the inhibition of the mono-nitrogen oxide radical and cyclooxygenase respectively. The evaluation of the photoprotective effect expressed a high protection factor (34.81) and no irritant effects. Chemical analysis of the crude extracts was carried out by FTIR, LC-MS and GC-MS. The FTIR spectral study revealed the presence of different functional groups such as alcohols, ketones and amines, indicating the richness of the extract in various metabolites. GC-MS and LC-MS studies revealed the presence of 15 bioactive compounds, of which 9 phenolics and 6 organic acid components were identified for the first time in P.nigra buds. This approach using lactic acid as an ecological solvent and ultrasound as an alternative energy source represents a good choice for the design of an extraction system of bioactive compounds with antioxidant, anti-inflammatory and photoprotective properties. Further studies are needed to extend the screening approach anti-irritancy to develop antioxidant-enriched.