Antioxidant Potential and Stabilization Studies of Sunflower Oil Using Sorbaria tomentosa Extract and its Cu(II)/Zn(II) Chelates

摘要

Sorbaria tomentosa,, commonly known as “Berre” is native to Himalaya and Hindukush range in Pakistan. Qualitative phytochemical screening as well as quantitative antioxidant potential of its ethanolic extract was evaluated. Antioxidant potential of the extract was determined using standard methods like DPPH, FRAP, total phenolics, total flavonoids, ABTS radical cation scavenging assay and β-carotene linoleic acid emulsion system. Cu(II) and Zn(II) chelates of ,,Sorbaria tomentosa,, were also prepared and their antioxidant potential was compared with the extract as well as with synthetic antioxidants (BHT and BHA). It was observed that ,,Sorbaria tomentosa,, is a good source of natural antioxidant that worked efficiently compared to respective chelates. Keeping in view less efficiency of chelated extracts, stabilization studies of sunflower oil were conducted with ethanolic extract (250, 500, 1000 ppm) of ,,Sorbaria tomentosa,,. Various parameters like PV, FFA and IV were estimated to evaluate stabilization of oil. ,,Sorbaria tomentosa,, extract (1000 ppm) showed almost same role during stabilization like BHA at ambient condition during a storage period of 45 days.