Exploring Green Food Packaging Properties of Bauhinia variegata, Prunus dulcis, Tectona grandis and Nelumbo nucifera – A Comparative Analysis

Objectives: The purpose of this current research is to develop suitable food packaging films with extended shelf using medicinal plant leaves. Methods: The four medicinal plants for their traditional food packaging leaves, namely Mantharai (Bauhinia variegata), Badam (Prunus dulcis), Teak (Tectona grandis), and Lotus (Nelumbo nucifera) were used. Qualitative determination of the phytochemical compounds in the aqueous extracts of all four leaves were done. The antioxidant activities were assessed by DPPH Radical Scavenging assay and Ferric Reducing Antioxidant Power assay. The antibacterial and antifungal activity was screened against the bacterial (Staphylococcus aureus, Escherichia coli, and fungal species Candida albicans, Aspergillus flavus of clinical importance using the disc diffusion method. Findings: B. variegata showed the highest flavonoid content of 2.273 ± 0.0021 mg Catechin Equivalent /100 mg and presented potent antioxidant activity in DPPH and FRAP assays. Among all the extracts screened, N. nucifera and T. grandis had the highest phenolic content of (886.5 ± 0.776 μg GAE/100 mg and 861.5 ± 1.211μg Gallic Acid Equivalent/100 mg respectively). The antimicrobial activity indicated high efficacy of B. variegata (17 mm against S. aureus at 500 µg/ml), followed by N. nucifera with reasonable inhibition zones (13 mm against C. albicans and 12 mm against E.coli both at 500 µg/ml. The other extracts had moderate to weak antioxidant and antimicrobial activity compared to the standard positive control. From the percentage inhibition of antibacterial activity, it was revealed that the extract of B. variegata was able to inhibit the growth of S. aureus up to 94.44 % and E. coli up to 94.12 % at the concentration of 500 µg/mL compared to Ciprofloxacin (100 %). Similarly, N. nucifera, P. dulcis, and T. grandis extracts displayed inhibition ranging from 0 % at 100 µg/mL to 84. 21%, 66. 67% and 35% at 500 µg/mL. Inhibition of C. albicans by B. variegata was recorded to be 94.12% while it was 60% for A. flavus. N. nucifera maceration reached 85.71 % inhibition of C. albicans and 47.06% for A. flavus. With P. dulcis and T. grandis extracts at a concentration of 500 µg/mL, the inhibition was recorded to be 63.16% and 70% respectively to that of fluconazole (100%). Novelty: This study explores the usage of Bauhinia variegata as eco-friendly green food packaging material. It is evidenced that due to their highly efficient antioxidant and antimicrobial characteristics, these natural polymers present in B. variegata might overcome oxidative stress and microbial harm in food and packaging products for sustainable and safe applications. Keywords: Phytochemical analysis, Antimicrobial activity, Antioxidant activity, Bauhinia variegata Linn, Food packaging