Comparison of two methods for determining in vitro intestinal absorption of nutrients using rats fed different diets

Absorption of sucrose, glucose, leucine and aspartate was studied using intestinal everted sac of rats fed on french bean diets namely PDR-14, HUR-137 and HUR-15 using casein as a control. Absorption of nutrients was monitored spectrophotometrically and by¹⁴C radio assay of metabolites using scientillation counting. The absorption pattern of amino acids was found to be similar but of glucose and sucrose differed. Glucose was found to be more absorbed than sucrose in spectrophotometer assay and the pattern reversed in radio assay. Absorption of sucrose and leucine were higher by rats fed on HUR-137 diet and similarly, more aspartate was absorbed when fed on HUR-15 diet as demonstrated by both the methods. Rats fed on HUR-137 diet exhibited higher glucose absorption as shown by spectrophotometric assay, but rats on HUR-15 diet by radio assay. Absorption of nutrients differed significantly between casein and french beans.