Analytical studies on Annabethi Chenthuram, a Siddha herbomineral formulations

Abstract

In Siddha system of medicine, herbs, metals, minerals, hydrochemicals, arsenics and animal products are predominantly used for medicine preparations. Annabethi is a common hydrochemical drug, which is popularly known as green vitriol (chemical name is ferric sulphate). Naturally Annabethi is collected in hills and also synthesized, which is green in colour with crystal form, nauseous astringent taste and has solubility in water. It is commercially prepared by mixing iron wire with sulphuric acid and evaporating the solution to crystallization. Annabethi chenthuram is commonly used in Siddha system of medicine for treating anaemia, fever and dysentery. Even though some research studies have been conducted on Ayurvedic kasisa bhasma (similar to Annabethi chenthuram in Siddha), there is no scientific work carried out on the Annabethi chenthuram. Hence, the present research work was focused on the in-house preparation and characterization of Annabethi chenthuram. Annabethi chenthuram was prepared, physico-chemical parameters were analysed and characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, X-ray fluorescence, scanning electron microscope and particle size analyzer. Physico-chemical parameters such as loss on drying (1.00 %), total ash (65.94 %), water soluble ash (1.864 %) and acid insoluble ash (39.02 %) were determined. Fourier-transform infrared spectra revealed an increase of iron content (peaks at 617 and 430) when compared to the raw drug. X-ray diffraction pattern confirmed the presence of α-Fe2O3 and absence of β-Fe2O3 in Annabethi chenthuram. X-ray fluorescence analytical data showed that the medicine contained iron (66.46 %) and iron oxide (93.58 %). These results provided scientific evidence for the conversion of iron sulphate into an edible and bioavailable form in Annabethi chenthuram.