Evaluation of a Spectrophotometric Method for Determination of Total Fecal Lipid

Abstract

Abstract A spectrophotometric method is evaluated for determination of total fecal lipid. Duplicate samples of fecal homogenate, an appropriate standard, and a blank, each in acidic, aqueous alcohol, are extracted with petroleum ether. The extracts are analyzed by the spectrophotometric, acid-dichromate oxidation method. The procedure is much briefer and simpler than current gravimetric and titrimetric methods for fecal fat, and a comparative study suggests that the values obtained are of equal diagnostic value to those obtained by the popular Van de Kamer [J. Biol. Chem. 177, 347 (1949)] method for total fatty acids. Fecal samples from patients with various degrees of steatorrhea gave results having a linear relationship between total lipid and total fatty acid excretion (coefficient of correlation, 0.995; regression formula, total lipid = 1.09 (total fatty acid) + 3.4). The slope of near unity indicates that the increased lipid excretion in steatorrhea is almost wholly accounted for by increased triglyceride and fatty acid excretion and that the unsaponifiable fraction remains relatively constant.