Effectiveness of corn stalk ash in reducing tannin levels and improving In vitro enzymatic degradation of polysaccharides in crop residues

Abstract

The condensed tannin content of three major plant by-products in the West African subregion, namely cassava peel (CP), plantain peel (PP) and cocoa pod husk (CPH) were measured. The values recorded for cassava peel and plantain peel were 2.0 and 1.8 per cent, respectively. Cocoa pod husk had the highest content (Amelonado–2.6 %; Tafo Hybrid–2.9 %; Amazonia–3.4 % dry wt). An aqueous extract of corn stalk ash, with a pH of 10.7, contained substantial amounts of potassium (51.0 ppm), sodium (16.4 ppm), chloride (22.4 ppm), and sulphate (9.5 ppm) ions. Treatment of the crop residues with corn stalk ash extract resulted in a timedependent reduction of condensed tannin content of all crop residues (84 % reduction in cocoa pod husk after 48 h of treatment) and improved in vitro rates of degradation of cellulose (CPH–72.1%, CP–116.1%, PP– 133.3 % after 48 h) and starch (CPH–107.5 %, CP–84.3 %, PP–82.2 % after 48 h). The findings suggest that treatment with corn stalk ash might be an effective means of detannifying and improving digestion of crop residues.

Ghana Journal of Science Vol. 44, 2004: 87-92