Hydroalcoholic extracts were prepared from the leaves of Ocimum sanctum, Boswellia serrata, rhizomes of Zingiber officinale and roots of Glycyrrhiza glabra. By using these extracts polyherbal syrup and suspension were prepared. The antioxidant study of these crude extracts and the prepared polyherbal formulations was carried out by DPPH radical scavenging activity and Nitric oxide scavenging activity method. All the extracts and the polyherbal formulations exhibited antioxidant activity in concentration dependent manner but the polyherbal formulations displayed better activity than that of their crude extracts. The better activity of the prepared formulations may be due to the combined activity of phytoconstituents present in these extracts. The results from the present study support the incorporation and utilization of herbs in the formulations to give better effect for the management of respiratory diseases by polyherbal formulations.
