Effect of Condensed Tannin of False Acacia Leaves on Protein Digestibility, as Measured with Rats

DOI Web Site

Bibliographic Information

Other Title
  • 蛋白質の消化に対するニセアカシア葉縮合性タンニンの影響
  • タンパクシツ ノ ショウカ ニ タイスル ニセアカシア ハシュク ゴウセイ

Search this article

Abstract

Condensed tannin of false acacia (Robinia pseudo acacia L.) was examined for its influence on protein digestibility, as measured with male rats. The results obtained were as follow: (1) The protein digestibility averaged 49.1% for false acacia leaves treated with chilled acetone and the addition of polyethylene glycol (PEG 4, 000) into a diet containing false acacia leaves increased the protein digestibility from 49.1% to 70.7% and the protein efficiency ratio from 2.74 to 3.48. However, the addition of PEG had no effect on the values obtained for a diet containing brewer's grains which were free from condensed tannin. (2) Percent of administered PEG recovered in faeces averaged 46% as water-soluble PEG for rats given a diet containing false acacia leaves while the recovery averaged 91% for rats given a diet containing brewer's grains. It seemed reasonable to say that condensed tannin formed a water-insoluble complex with PEG in the alimentary canal, which resulted in the increase of protein digestibility and the decrease of water-soluble PEG in the faeces of rats given faelse acacia leaves. (3) Crude condensed tannin was prepared from fresh leaves of false acacia. The depression of protein digestibility was caused by the feeding of a diet containing the tannin, both as free tannin and as protein-tannin complex and the protein digestibility decreased with increasing tannin content in a diet. The digestibility of protein-tannin complex was also improved by the administration of PEG. These results indicate that the low nutritional value of protein in false acacia leaves is due to the presence of condensed tannin.

Journal

Details 詳細情報について

Report a problem

Back to top