An Eco-benign synthesis of multifunctional TPP-Co3O4 NPs by polyphenol rich tea infusion extracted by microwave method with enhanced biomedical applications

Abstract

Green tea is widely known for its health benefits and is a valuable source of polyphenols that can be used for various physiological activities. A highly effective method involving microwave assistance was employed for polyphenol extraction from green tea leaves. The response surface methodology (RSM) enhanced the extraction parameters to produce a polyphenol-rich tea infusion to synthesize TPP-Co₃O₄ NPs. To look into the effect of different factors such as MW intensity (A), temperature (B), time (C), and solvent/tea ratio (D), we conducted single-factor experiments. We applied RSM using a four-factor, three-level Box-Behnken design (BBD) to optimize TPC yield. The optimal conditions for TPC contents were as follows: A = 600 W, B = 75 °C, C = 400 sec, and D = 30 mL/g, resulting in TPC contents of 51.21 mg GAE/g tea. The polyphenol-rich tea infusion was subjected to prepare cobalt oxide nanoparticles (TPP-Co₃O₄ NPs). Several physicochemical techniques were used to investigate the synthesized nanoparticles. TPP-Co₃O₄ NPs exhibited effective inhibition potential against gram positive Staphylococus aureaus (S. aureaus) and gram negative Escherchia coli (Escherichia coli) bacteria. Furthermore, TPP-Co₃O₄ NPs exhibited significant antioxidant potential, achieving an 88 % reduction in DPPH free radicals. TPP-Co₃O₄ NPs' enormous surface area and negligible size could explain these remarkable biological activities.