By Abbas Nazil
A new study has found that fractions of Tinospora cordifolia, a medicinal plant, can serve as an effective and environment-friendly inhibitor of carbon steel corrosion in seawater.
Researchers from Indonesia, India, Morocco, Saudi Arabia, and Indonesia’s National Research and Innovation Agency (BRIN) discovered that the plant-based inhibitor significantly reduces corrosion current density, offering a greener alternative to conventional synthetic chemicals.
The study evaluated the Tinospora cordifolia fraction (TCF) at varying concentrations and temperatures using electrochemical methods such as potentiodynamic polarization and electrochemical impedance spectroscopy.
At 150 milligrams per liter, the inhibitor achieved an impressive efficiency of 90.89 percent by PDP and 92.25 percent by EIS, demonstrating a strong ability to prevent rusting and surface degradation.
Although the efficiency declined slightly from 90.89 percent to 83.74 percent as temperature increased from 300 to 320 Kelvin, the inhibitor remained effective even at elevated conditions.
According to the research, the inhibitory mechanism is mixed-type but predominantly cathodic, meaning it mainly reduces oxygen reactions on the metal surface.
The bioactive compounds in Tinospora cordifolia adsorbed spontaneously on the steel, forming a protective film that followed the Langmuir adsorption isotherm with a free energy of –26.73 kJ/mol.
Computational analysis using density functional theory confirmed that moupinamide, the main active compound, interacts strongly with the steel surface, contributing to corrosion resistance.
The findings position TCF as a promising “green” corrosion inhibitor capable of replacing toxic industrial chemicals used to protect steel infrastructure in marine environments.
Researchers highlighted that its bio-based nature makes it cost-effective, sustainable, and suitable for industries such as offshore construction, shipping, and energy.
The study recommends further development to optimize extraction processes and improve long-term durability for industrial-scale applications.
The discovery of Tinospora cordifolia’s corrosion-inhibiting properties marks a vital step toward eco-conscious industrial materials protection.
