| To achieve a rapid and accurate determination method for single-cell lipid, sulfo-phospho-vanillin（SPV） reaction conditions were optimized and the application of SPV reaction in determination of microbial intracellular lipid was discussed. The optimal SPV reaction conditions were that oil samples were added with 2 mL of 98%H2 SO4 keeping in 90℃ water bath for 20 min， after they were cooled to room temperature, 3 mL of vanillin-phosphoric acid solution（prepared with 34%phosphoric acid solution） was added for color development and absorbance measurement was made at 530 nm after 20 min of color reaction to eliminate the non-oil components interference. Under the optimal conditions, lipid contents of Schizochytrium sp. and Crypthecodinium cohnii were detected， and there was no significant difference in lipid determination comparing with macro-gravimetric method. Thus, SPV reaction was proved to be a simple, accurate, rapid method for detecting microbial intracellular lipid which could be used as a routine analytical method for the determination of single-cell lipid. |
