Optimum conditions on extraction of tannin from Leucaena leucocephala

The optimum conditions, including four main factors: ratio of liquid to material, extraction temperature, extraction time and extractant concentration, for extracting tannins from leaves and stems of Leucaena leucocephala were optimized by using a combined method of single factor analysis and orthogonal experiment design. The results showed that the optimum conditions of each factor in tannin extraction were: ratio of liquid to material 40∶1, extraction temperature 50 ℃, extraction time 40 min and acetone concentration 50%. The extracting rate of the tannin from the leaves and stems of L. leucocephala was 2.54%. Key words: Leucaena leucocephala; tannins; extraction