4202 Abstract. – OBJECTIVE: Natural wound dressings composed of gelatin (GEL) and chi- tosan (CH) impregnated with bioactive com- pounds (Nigella sativa oil) were prepared and characterized to evaluate their potential appli- cation. MATERIALS AND METHODS: The formu- lated composite was subjected to γ-irradiation. In vitro, the ferric-reducing antioxidant pow- er (FRAP) assay and antibioflm activities were evaluated. In vivo, the tissue wound-healing pro- cess was studied by applying GEL-CH-Nigella in dorsal skin rabbit tissue. On days 7 and 14, the biochemical biomarker and histological analysis were determined. RESULTS: At 10 kGy, FRAP assays exhibit- ed the highest antioxidant activity (380 mmol/ kg). A signifcant inhibition of anti-bioflm activi- ty was observed against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) (p<0.01). Fourteen days post-surgery, a signifcant reduc- tion in thiobarbituric acid-reactive compounds (TBARs) was observed compared to the GEL- CH group. Concerning oxidative stress status, GEL-CH-Nigella signifcantly improved superox- ide dismutase (SOD), catalase (CAT), and gluta- thione peroxidase (GPx) activities. A histological analysis revealed that GEL-CH-Nigella accelerat- ed wound closure and improved collagenisation and enhanced epidermal tissue thickness. CONCLUSIONS: These results indicate that GEL-CH-Nigella wound dressing is a promising biomaterial for engineered tissue. Key Words: Nigella sativa, Gelatin, Chitosan, Wound dressing, γ-irradiation, Anti-biofilm inhibition, Oxidative stress, Rabbit model. Introduction Many advantages of chitosan (CH) on skin injuries have been reported 1 including attractive pharmacological actions such as biocompatibility, antibacterial, anti-infammatory, hemostatic and cell skin regenerative behavior. The amino and hydroxyl groups of these molecular chains allow the grafting of other groups and chemical compo- nents to enhance certain biological functions. Despite its favorable biological properties, the weak mechanical strength of CH has limited the scope of its application 2 . Many physicomechani- cal properties are needed in an ideal wound dress- ing material, such as high elongation and good tensile strength 3 . Gelatin (GEL), a collagen-de- rived substance, exhibits attractive mechanical properties that associate with desired biocompat- ible properties 4 . GEL does not trigger any immune response in the human body 5 . It is made of proline, hydroxy- proline and glycine which help cells join togeth- European Review for Medical and Pharmacological Sciences 2023; 27: 4202-4210 G. BEN SALAH 1 , S. JEBAHI 2,3 , S. BESSALEH 4 , M.A. AHMAD 5 , H. KHIREDDINE 6 , M. ABDULGHANI 7 , N. MEJRI 8 1 Department of Pharmacology and Toxicology, Unaizah College of Pharmacy, Qassim University, Buraidah, Al Qassim, Saudi Arabia 2 Energy and Matter for Nuclear Sciences Development, National Center for Nuclear Sciences and Technologies, Sidi Thabet, Tunisia 3 Laboratory of Biodiversity, Molecules and Applications (BMA), Higher Institute of Applied Biology Medenine, University of Gabes, Gabes, Tunisia 4 Livestock and Wildlife Laboratory, Arid Lands Institute (I.R.A), University of Gabes, Medenine, Tunisia 5 Department of Mathematics, Physics & Statistics, University of Guyana, Turkeyen Campus, Georgetown, Guyana 6 Process Engineering Department, Faculty of Technology, University of Bejaia, Bejaia, Algeria 7 Department of Pharmacology, International Medical School, Management and Science University, Shah Alam, Selangor, Malaysia 8 Laboratory of Biotechnology and Nuclear Technologies, National Center of Nuclear Sciences and Technologies, Sidi Thabet, Tunisia Corresponding Author: Ghada Ben Salah, Ph.D; e-mail: G.SALAH@qu.edu.sa Skin healing effects of an innovative polymer-based oil Nigella sativa: a rabbit model experimental study