Microbial transformations are important tools for renewing natural resources (such as hydroxycinnamic acids) into commercially valuable products. Ferulic acid is one of the most abundant hydroxycinnamic acids that accumulates mainly in the cell wall of cereal plants through covalently crosslinking to lignin and polysaccharides. During the process of side chain degradation of ferulic acid, several value added products can be formed such as vanillin and vanillic acid, which are the major ingredients of natural vanilla flavour. Schizophyllum commune, Paecilomyces variotii and Streptomyces sannanensis were selected for their capabilities to biotransform ferulic acid into vanillic acid. The biotransformed products of ferulic acid were detected by using thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). An efficient isocratic HPLC method has been developed to separate ferulic acid and its biotransformed products. The identities of the HPLC purified products were further confirmed by mass spectrometry. Vanillic acid was observed as a major degradation product with transient accumulation of vanillin, when Schizophyllum commune, Paecilomyces variotii and Streptomyces sannanensis were grown individually on minimal medium containing ferulic acid as sole carbon source. Various cultural parameters have been standardized to enhance the product(s) formation. In case of P. variotii, supplementation of glucose along with ferulic acid (10 mM) resulted in a two-fold increase in the production of vanillic acid (226 mg/l) as compared to the incubation with ferulic acid alone at 37 0C. Streptomyces sannanensis showed a maximal accumulation of vanillic acid (400 mg/l) after 16 days of incubation with 5 mM ferulic acid at 28 0C. Among other parameters, supplementation of trace salts in the minimal medium containing ferulic acid as sole carbon source showed a marginal increase (ca. 10%) in vanillic acid accumulation. When cells of S. sannanensis pre-grown on ferulic acid were used as inoculum, a maximum amount of 467 mg/l vanillic acid accumulation was observed after 12 days of incubation. A stable accumulation of vanillic acid led to its purification, which was performed by gel filtration chromatography using Sephadex™ LH20 matrix.