Antioxidant Evaluation, Acute Toxicity Screening and Heavy Metal Analysis of a Poly Herbal Mixture

Abstract

The persistent exposure of plants to contaminants is a great public health concern. This makes it pertinent to determine the safety levels of herbal  extracts especially for the presence of heavy metals. RUZU bitters is a polyherbal plant extract with demonstrated antidiabetic activity. It is  composed of the medicinal plants; Uvaria chamae, Curculigo pilosa and Colocynthis citrullus. This study is aimed at investigating the acute toxicity,  antioxidant activity and heavy metal contents of RUZU bitters. Phytochemical screening and polyphenolic content were done using standard  methods. The acute toxicity study was carried out using modified Lorke’s method while the heavy metals analysis was carried out using Atomic  Absorption Spectrophotometer. Antioxidant potential of the extract was evaluated using 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging  method. The results of the phytochemical screening revealed the presence of carbohydrates, reducing and deoxy sugars, saponins, phenolics,  flavonoids and tannins. The extract showed significant polyphenolic content with total phenol content of 30.22 ± 3.42 mgGAE/g and total flavonoid  content of 43.5 ± 2.17 mgQE/g. Further, it demonstrated low radical scavenging activity with IC₅₀ of 236.32μg/mL. The metal content showed  1.09mg/L for Cr, 0.10 mg/L for Zn, 2.10mg/L for Fe, 0.23mg/L for Mn, 0.20mg/L for Cu, 0.06mg/L for Cd, 6.50mg/L for Na, 37.50mg/L for K,  32.00mg/L for Mg, 8.90mg/L for Ca and nil for Pb and Cd. RUZU bitters has little radical scavenging activity, hence low antioxidant potential. The  little or no presence of heavy metals showed that it is safe for daily consumption.