Abstract Chitosan possesses intrinsic antimicrobial activity, whereas Aloe vera leaves are rich in antioxidants and phenolic compounds that can enhance polymeric bioactivity. In this study, advanced carboxymethyl chitosan/polyvinyl alcohol (CMCS/PVA) films functionalized with Aloe vera rind extract (RE), a rarely explored bioactive byproduct, were developed and evaluated for their structural, mechanical, and antibacterial properties. O -carboxymethyl chitosan ( O -CMCS) and N , O -carboxymethyl chitosan ( N , O -CMCS) were synthesized from 90%-deacetylated chitosan, with degrees of carboxymethylation of 86.6% and 107.6%, respectively. Among tested solvents, an ethanol/water (4:1 v/v) mixture proved the most effective solvent for extracting phenolic and non-phenolic antioxidants from Aloe vera rinds. Incorporation of up to 20% RE enhanced the tensile performance of CMCS/PVA films, with RE/ N , O -CMCS/PVA showing greater strength than RE/ O -CMCS/PVA. Ethanolic RE exhibited stronger antibacterial activity against Propionibacterium acnes ( P. acnes ) than Staphylococcus aureus ( S. aureus ). The 20%-RE/ O -CMCS/PVA inhibited bacterial growth to the greatest extent, whereas the 10%-RE/ N , O -CMCS/PVA film was as effective as the 15%-RE/ O -CMCS/PVA films. Among all tested formulations, the 10%-RE/ N , O -CMCS/PVA film demonstrated the optimal combination of mechanical strength, hydrophilicity, and antimicrobial efficacy. These findings highlight Aloe vera rind as a sustainable source of functional additives and emphasize the key role of CMCS substitution patterns in tuning polymer network interactions. The developed composite films provide a green and multifunctional platform for eco-friendly bioactive film applications, exhibiting enhanced mechanical and antimicrobial properties, with potential relevance to advanced functional film platforms.
Pankaew et al. (Thu,) studied this question.