Development of antioxidant active PVA films with plant extract of Caesalpinia ferrea Martius

In this work, antioxidant active films of poly (vinyl alcohol) – PVA incorporated with plant extract of Caesalpinia ferrea Martius (PF) were developed. The films were prepared through the solution casting technique. The concentrations of the plant extract used in the films were 0, 1 and 5% w/w. The analyses of phenolic and flavonoid content of the extracts resulted in 464.4 and 10.54 mgEQU/g, respectively. Antioxidant activity showed an index of 42.22 and 87.90% efficiency for free radical capture (DPPH) and total antioxidant capacity (TAC) techniques, respectively. Through the results of thermal analyses, a decrease in the degree of crystallinity and enthalpy of fusion were observed. An increase in thermal stability occurred after the incorporation of plant extract in the PVA matrix. For the mechanical test, an increase in tensile strength was noted. An increase was verified for water vapor permeability with the addition of plant extract. These films showed potentially antioxidant activities. It can be concluded that the incorporation of Caesalpinia ferrea Martius extract in the PVA had promising results, therefore, presenting an alternative for conventional passive packaging. •Development of PVA films added with Caesalpinia ferrea Martius tree extract.•The plant extract showed good antioxidant activities.•The incorporation of plant extracts in the PVA films was indicated using FTIR.•Changes in the thermal and mechanical properties of PVA were observed.•The antioxidant activity remained considerable even after the addition in PVA.