BOUABDELLI, SarraBENDAHMANE, ImaneBENNABI, FARID2025-07-132025-07-132025http://dspace.univ-temouchent.edu.dz/handle/123456789/6638The use of plants in cosmetics dates back to ancient times. Cosmetics play an important role in everyday life. This study explores the formulation and evaluation of natural cosmetics based on Curcuma longa, including a soap, a hair oil, and a body oil, highlighting their therapeutic properties. The antioxidant activity, measured by the DPPH test, reveals a remarkable efficacy of the oils (IC50 of 4.0569 mg/ml for hair oil and 2.9131 mg/ml for body oil), comparable to ascorbic acid (IC50 of 1.2881 mg/ml), while the soap shows reduced activity (IC50 of 19.3704 mg/ml), likely due to degradation during saponification. The antimicrobial activity, assessed by the disk diffusion method, demonstrates that the soap excels against Bacillus subtilis (inhibition zone of 16 mm) and shows moderate efficacy against other pathogens, unlike the inactive oils, suggesting a dependence on the formulation matrix. The anti-inflammatory activity, measured by membrane stabilization (70% for oils, 30.8% for soap) and hemolysis (30.2-30.8% for oils, 10.4% for soap), confirms the potential of the oils, though inferior to Diclofenac (90% and 70.2%). The physicochemical properties (suitable pH, pleasant texture) and cosmetic tests (no irritation, good hydration) validate their tolerance and appeal. These results highlight a successful synthesis of tradition and innovation, positioning these cosmetics as a sustainable alternative to synthetic products, with prospects for optimization (e.g., nano-encapsulation, expanded clinical trials) and global commercialization to meet the growing demand for green care.frAnti-inflammatory activity, Antimicrobial activity, Antioxidant activity, Curcuma longa, Natural cosmetics.Thesis