Standardization of a Formulation of Timogar and Ferula Assa-Foetida Dry Resin Extract and its Biological Activity

A dry extract of Ferula assa-foetida L. gum-resin was obtained. A formulation was developed on the basis of the extract and timogar preparation. Esters were qualitatively determined using the reaction with vanillin solution (1%) in conc. H₂SO₄; polysaccharides, with phenol in the presence of conc. H₂SO₄; coumarins, by TLC using umbelliferone standard. The quantitative content of timogar was determined using UV spectrophotometry; total phenolic compounds, the Folin–Ciocalteu method. The flavonoid content was also quantitatively determined. The formulation was standardized for description, solubility, mass loss on drying, heavy metals, authenticity (timogar, esters, polysaccharides, and coumarins), and quantitative content (timogar, total phenolic compounds, and flavonoids). The timogar content was 0.009 – 0.011%; total phenolic compounds, at least 75%. The flavonoid content was quantitatively determined using spectrophotometry and the reaction with an AlCl₃ solution (10%) and should be at least 89% when recalculated using cynaroside as a standard. Experimental studies of acute and chronic toxicity showed that the proposed formulation was nontoxic and could be classified as hazard class 6 (relatively harmless). The immunostimulatory activity of the formulation exceeded by 1.3 times that of timogar alone.