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Four liter culture medium was prepared for Aspergillus niger, and distributed equally in 40 Erlenmeyer flasks of 250 mL i.e., each flasks contain 100 mL of culturing medium. Seed flaks were prepared by inoculating with A. niger spores and incubated at 26 _C for 3 days. Within two to three days, fungus growth was observed. The remaining flasks were inoculated by transferring spores from seed flasks. 6-Dehydroprogesterone (1) (300 mg) was dissolved in methanol (20 mL), and distributed to 40 flasks containing 3–4 days old cultures of A. niger (7.5 mg in each flask). These flasks were placed over rotary shaker for fermentation for 12 days at 26 _C. On completion of fermentation reaction, the fungal mass was filtered off, and extracted three times with CH2Cl2 (24 L). The extract was dried over Na2SO4 (anhydrous) and concentrated under reduced pressure to obtain a brown gum (2.1 g). This gum was fractionated with silica gel column chromatography with hexane: acetone mixtures of increasing polarity. The fractions were compiled together through comparative TLC analysis, which yielded five main fractions (1–5). Further purification was carried out using recycling HPLC.