BENGALURU: Researchers at the Indian Institute of Science (IISc) have discovered enzymes that can successfully degrade toxic chemicals in industrial wastewater in the presence of sunlight. This research could be a game-changer in treating wastewater and reducing toxicity.
This will be important, since according to a Karnataka State Pollution Control Board (KSPCB) report, 68 Bengaluru lakes fall under the ‘D’ and 40 in the ‘E’ category, which only qualify for the propagation of wildlife and fisheries and for industrial cooling, irrigation and controlled water disposal.
IISc scientists have produced nano-sized enzyme mimetics or nanozymes, manufactured in the lab that can mimic natural enzymes. These nanozymes can also overcome challenges such as easily damaged, complex production procedures, high costs, and difficulties in recycling – which generally makes natural enzymes unpractical.
“Enzymes are proteins that catalyse a majority of biological reactions in living systems. However, the practical use of natural enzymes is greatly hindered. Laccase, a natural enzyme used for degrading phenols in industries, is extracted from a fungus called white rot, but the amount of enzyme produced depends on how much of the fungus is available,” said Subinoy Rana, Assistant Professor at Materials Research Centre (MRC), IISc, and corresponding author of the paper published in Nanoscale.
He added that such enzymes can be made in only milligram amounts and is an expensive affair. Another problem is storage, most of the natural enzymes are temperature-sensitive and require storage at -20°C. However, nanozymes that researchers produced in the labs can mimic the properties of natural enzymes and overcome all the problems including producing them at an industrial scale at a minimal cost.
The IISC team tested the nanozyme’s effect on common effluents that pollute water such as phenols and dyes and discovered that it could degrade even small (micromolar) quantities of the products within ten minutes when placed under sunlight.
Scientists synthesised the nanozyme on a platinum-containing called NanoPtA, which can be converted into powder form for industrial use. “It mimics the function of oxidases – natural enzymes that remove hydrogen from substrates (the underlining layer) in the presence of oxygen to give water and can withstand a range of pH and temperature changes,” said the paper.