Abstract: An improved process for recovering Indicine-N-oxide from plant sources which involves water extracting the plant material, preferably by water buffered at pH 7, followed by adsorbing the Indicine-N-oxide from the extract, after which the Indicine-N-oxide is eluted from the adsorbent in alcoholic solution, then concentrated and purified as heretofore.Desirably, the adsorbed Indicine-N-oxide is water washed prior to elution so as to remove any water soluble impurities that had been adsorbed from the extract.A preferred adsorbent is a cross linked polystyrene.

Abstract: A quantitative evaluation of the intestinal microflora is made by administering to an animal organism an effective amount of novel chemical conjugates of a bile acid or related acid with an amino acid which will be cleaved from the bile or related acid by the enzymes elaborated by the intestinal microflora and then measuring the amount of the released amino acid in the urine after a predetermined time interval. The novel compounds and their use in in vitro tests are included in the invention.