“The developed systems were efficient in removing hazardous contaminants, including heavy metals like cadmium, nickel, and hexavalent chromium, as well as pesticides like chlorpyrifos. Laboratory validation showed removal efficiencies as high as 92% for heavy metals and 96% for pesticides. The researchers also found that the biochar–microbe immobilised complexes achieved 31% to 48% higher efficiency compared to using biochar or microbial cells independently,” Dr Vaishakh told TOI.The study revealed that the effectiveness of the system lay in its dual-action mechanism. Biochar physically adsorbed pollutants onto its porous surface, while the immobilised microbes biologically degraded or transformed these toxins into harmless forms. This synergistic interaction significantly enhanced bioremediation efficiency.“The biochar–microbe systems improved soil water-holding capacity by up to 41.5% and enhanced crop growth indicators such as seed vigour index in plants including spinach, okra, and tomato. These findings highlight the potential of the technology to improve soil health and crop productivity,” explained Dr Vaishakh.The research group secured a patent titled ‘Method of Developing Pseudomonas stutzeri Immobilised Rice Husk Biochar.’ The work was primarily carried out by Soumya Koippully Manikandan under the guidance of Dr Vaishakh Nair as part of her thesis—’Microbial Cell Immobilised Biochar for the Bioremediation of Metal Ions and Pesticide from Water and Soil’.“Indian soil face a threat from the industrial waste and excessive agricultural chemicals with toxic heavy metals and pesticides, which not only reduce soil fertility but also pose serious health risks. Converting locally available farm residues into biochar offers a sustainable solution in restoring soil health. It helps manage agricultural waste, and supports efforts like National Mission on Sustainable Agriculture (NMSA) and PM Programme for Restoration, Awareness Generation, Nourishment, and Amelioration of Mother Earth (PM-PRANAM) to promote climate-resilient, food-secure agriculture,” added Dr Vaishakh.
