A practical method of extracting mimosine from ipil-ipil, Leucaena leucocephala, leaves and its effect on survival and growth of Penaeus monodon juveniles

Abstract

Soaking fresh ipil-ipil, Leucaena leucocephala, leaves in tap water (1:1, v/v; or 50 g in 500 ml) for 30-48 hours with a water change after 24 hours extract atleast 90% of its mimosine, a toxic lysine derivative. This extraction procedure is more economical and practical for fish farmers than the use of dry or moist heat or iron compounds.

Soaked or unsoaked leaves of Peruvian or Hawaiian ipil-ipil Leucaena leucocephala formed 1/3 of trial diets fed to Penaeus monodon juveniles (1-2 g). Other protein sources consisted of fish and shrimp-head meals. A diet without ipil-ipil leaves (FS) served as the control.

After 8 weeks, the mass weight of shrimp fed the FS and soaked Hawaiian leaf diets (HLS) was significantly (α= 0.05) higher than soaked (PLS) and unsoaked (PLU) Peruvian leaves. The HLS group had a significantly higher survival rate than the PLS and PLU groups but not the FS-fed shrimps; survival among shrimp fed unsoaked Hawaiian leaves (HLU) was zero.

It was found that the Hawaiian variety of ipil-ipil leaves when soaked for 24 hours can be incorporated in the P. monodon juvenile diet with good survival (87%) under laboratory conditions. However, the optimum amount of leaves to be included in a low cost and efficient diet has yet to be determined.