Abstract
The effect of concurrent addition (5%) of various vegetable residues or konjac mannan was examined in weanling rats fed a toxic level (5%) of Food Red No. 2 (amaranth) in a semi-purified diet. The vegetable residues were prepared from great edible burdock (gobo), carrot roots (ninjin), Japanese raddish roots (daikon) and bamboo shoots (takenoko) by treating successively as follows: grinding with running water by a ISE-disposer, boiling in water for 20min, filtering centrifugally and washing thoroughly with ethanol. Air-dried sample was powdered by a Wiley mill with 1mm sifter (crude vegetable residues).
The following results were obtained.
(1) All the residues completely prevented the growth retardation caused by the addition of 5% amaranth to a purified basal diet.
(2) This effect was closely associated with the improvement of food efficiency, the value completely restoring up to that of the basal diet group.
(3) Konjac mannan (water-soluble polysaccharide, a glucomannan from thet ubers of Amorphophallus konjac, K. Koch) showed a similar but slightly less effect.
(4) The beneficial effect of these indigestible polysaccharides was apparently enhanced when the supply of the essential trace elements (Zn, Cu and Mn) is limited to the marginal levels.
(5) Demineralized gobo-residue also improved the balance of these elements.
Irrespective of observations 4 and 5, we concluded that the beneficial effect of the vegetable residues should be related to the other mechanism (s) than the improvement of mineral balance because the latter is small.
