Correlation Relationship between Phase Inversion of Pickering Emulsions and Biocatalytic Activity of Microbial Transformation of Phytosterols

Microbial transformation of hydrophobic phytosterols into the pharmaceutical steroid precursors AD (androst-4-ene-3, 17-dione) and ADD (androst-4-diene-3, in a water–plant oil two-phase system by Mycolicibacterium neoaurum is paradigm interfacial biocatalysis Pickering emulsions stabilized bacterial cells. In present work, phase inversion emulsions—i.e., turning from water-in-oil (W/O) oil-in-water (O/W) ones—was observed during microbial presence high concentrations crystal phytosterols. It was found that there correlation relationship between behaviors biocatalytic activity utilizing M. as whole-cell catalyst. Efficient under phytosterol loadings achieved due to formation O/W where took place. Under optimal conditions (volume ratio soybean water: 15:35 mL, concentration oil: 80 g/L, glucose co-substrate aqueous culture medium: 10 g/L), reached 4.8 g/L based on whole broth (16 phase) after for 9 days.