Metals corrode easily which leads to environmental hazards, structural cracks and economic loss. To mitigate metals from corrosion, the organic coating was preferred since it aids as a barrier to separate oxygen, corrosive ions and water. However, some organic inhibitors are toxic in some extent. The significance of the research is to deepen the corrosion studies using natural biopolymer materials especially rich in nitrogenous matter. Zinc oxide, titanium dioxide, papaya leaves and DGEBA (diglycidyl ether of bisphenol A) were used in this study. The presence of alkaloid material and nitrogenous matter in the papaya leaf provides a beneficiary effect by accelerating the corrosion resistance in carbon steel. Mechanical properties/electrochemical behavior of carbon steel was studied by impedance and polarization test in an acidic environment. The microhardness of nano-hybrid composite was found to be 800 HV200 with surface wettability of 109.5° (hydrophobic). In addition, corrosion rate of composite coating was reduced by 79% and 22.5% from virgin and DGEBA coating medium, respectively. An acoustic emission (AE) test was also taken to monitor the characterization of these materials. The acoustic emission parameters are within the error margin of around 60% of the operating load. Microstructural analysis shows the morphological behavior of the coated substrate. Biopolymer shows a prominent anti-corrosive performance for carbon steel at 0.5 mol/L. The results are justified in comparison with nano-hybrid composite biopolymer coating (ZnO–TiO2–PLE) to the organic polymer coating (DGEBA).