The role of extracted Patchouli residue microparticle on the mechanical and microbial properties macroalgae biopolymer

Abstract Macroalgae is extensively being used to develop eco‐friendly biopolymer or biodegradable films, but have inferior mechanical strength. This study aims to enhance the mechanical properties of seaweed films by incorporating Patchouli microparticles (PMP) derived from dried Patchouli plants (DP‐PMP) and extracted residue (ER‐PMP) from Patchouli extraction process widely use in the perfume and cosmetic industry. The PMPs, were incorporated into films forming solution at varying concentrations (1%, 3%, 5%, and 7% wt/wt) respectively. Despite similar thermal properties, the inclusion of ER‐PMP resulted in an increasing ash residue content with an increase in concentration. The optimal tensile strength was achieved with a 3% PMP loading, while higher concentrations resulted in a decline in strength. Notably, the sample containing 1% PMP demonstrated superior elasticity. Moreover, with increasing concentrations of PMPs, all samples displayed elevated surface roughness and enhanced hydrophobicity. All samples display significant antimicrobial activity against E‐coli and Salmonella sp.; however, the sample incorporating ER‐PMP showed less effect. In summary, the study suggests that DP‐PMP and ER‐PMP can serve as effective fillers to enhance the mechanical properties of seaweed biofilms, with an optimal loading of 3%. Their antimicrobial activity renders them suitable biopolymers for active packaging in food applications and other purposes. Highlights Patchouli microparticle (PMP) enhance the properties of seaweed film. Film's surface morphology and hydrophobicity changed with increase in PMP. Introduction of either PMPs increase antimicrobial properties of the film. PMP from extracted residue (ER) provide lower antimicrobial activity. 3% DP‐PMP gave the optimum properties of the film for overall attributes.