Indian scientists have synthesized a low-cost gold nano biocomposite material from onion peel with anti-inflammatory and antioxidant properties that can pave the way towards an effective herbal drug.
The secondary product of metabolism of plants, such as flavonoids, demonstrates high degrees of antioxidant, anti-inflammatory, and anti-cancer activities. Among flavonoids, quercetin which is found in many fruits, vegetables, red onions, plays an important role in decreasing inflammation bringing down the level of various cytokines.
Scientists from the Institute of Advanced Study in Science and Technology (IASST), an autonomous institute of the Department of Science & Technology (DST), GoI utilized the onion (Allium cepa) peel for the synthesis of gold nano bio-conjugate.
The team led by Dr. Devasish Chowdhury, Associate Professor, extracted the crude onion peel and subjected it to fractional distillation with ethyl acetate, butanol, methanol, and water. These fractionate were tested for various antioxidant activities.
The ethyl acetate fractionates showed high antioxidant activities in all the assays. The component in onion peel identified as quercetin was found in very high quantity. The team then prepared bio-conjugates or stable compounds with gold nanoparticles with the help of these fractionates. The nano bio-conjugates prepared were not found to be toxic to cells and did not show toxic effects on skeletal muscles tissues. The Reactive Oxygen Species (ROS) reduction of nano bio-conjugate showed a marked reduction of 76.77% at a maximum concentration of 200 µg/ml, whereas OPD showed 68.17 %. The finding recently published in the journal ‘ACS Omega’ could be a step towards effective, low-cost medicines from biocomposites of natural substances.