Optimization of Downstream Process Parameters for Isolation of Androstenedione Using Statistical Approach

4-Androstenedione (AD), a 19-carbon steroid hormone is an oxidation product of phytosterol fermentation by Mycobacterium sp. The isolation of the product from the fermentation broth is a challenging task. Downstream processing is an important aspect of all biotechnological processes and has significant implications on quality and yield of the final product. In the present study, the statistical approach was employed to optimize the various parameters for the downstream processing of AD. The quantity of Hyflow (filtration aid) was optimized as 5%, initially using the one variable at a time method. Further the factors: rpm, volume, solvent polarity and extraction temperature were studied using full factorial design. Analysis of the experiment showed that the polarity and the extraction temperature had maximum impact on the AD extraction. Selection of solvent for extraction procedure was carried out using one variable at a time (OVAT) technique. Ethyl acetate showed maximum product recovery. A Central Composite Design of “response surface methodology” was conducted to optimize the most significant factors of downstream process, to maximize the product extraction. The optimized model shows rpm-3500, solvent volume-5V and temperature-30°C gives maximum extraction of androstenedione. Index Terms Androstenedione, downstream processing, Hyflow, solvent extraction, full factorial design, response surface methodology. ________________________________________________________________________________________________________