Native wild plants in Karachi, Pakistan: Rich source of antioxidant raw material.

Extracts of nine plants were studied for DPPH radical scavenging and reducing abilities. Pentatropis spiralis, Calotropis procera, Helitropium curassavicum, Withania somnifera and Chenopodium album showed reducing power ranging from 34% to 146%. Suaeda fruticosa, Trianthema portulacastrum, Pluchea lanceolata and Rumex dentatus has excellent antioxidant potential proved by their DPPH scavenging and reducing power. 1000 mu g/10 mu l chloroform extract of S. fruticosa gave 92% scavenging with IC50 value less than 0.7 mu g/10 mu l while its hexane extract possessed 80% reducing activity at 100 mu g/10 mu l concentration. DPPH free radical scavenging by methanolic extract of Trianthema portulacastrum was 60% and 76% at 1000 and 100 mu g/10 mu l respectively with IC50 value of 0.03 mu g/10 mu l while the reducing activity of 124% at 100 mu g/10 mu l. Methanolic extract of P. lanceolata showed 91% and 70% scavenging activity at 1000 and 100 mu g/10 mu l with IC50 value of 0.7 mu g/ 10 mu l. Reducing power is comparable with the reference BHA standard that is 98% at 100 mu g/10 mu l concentration. Rumex dentatus' extracts are excellent DPPH scavengers and hydrogen donators produced 156% reduction. Chloroform extract was inefficient antioxidant. These results make these plants a candidate for future research for treating ailments due to imbalance in free radicals.