Antipseudomonal Ergosteryl Triterpenes from the Paste of Spondias pinnata kruz. Bark, Pre-Treated with Curd-Brew

Two new ergosteryl triterpenes were isolated from ethnopharmacological lead of Indian origin consisting of a paste of Spondias pinnata barks, pre-treated with curd brew. The chemical structures of the newly isolated compounds were established from detailed IR, 1H NMR, 13C NMR, GCMS and HRMS spectroscopic analyses. The triterpenes were evaluated for their antipseudomonal activities against a tetracycline and ampicillin-resistant strain of Pseudomonus aeruginosa by disc diffusion method. One of the compounds exhibited significant protection against the test microbe, comparable to streptomycin.