Nutritional Composition of Duckweed (Lemna minor) Cultured with Inorganic Fertilizer and Organic manure in Earthen Ponds

Abstract

Duckweed (Lemna minor) have been used for several years to recover nutrients from wastewater and as feed ingredient for livestock, including fish and poultry. This study aimed at assessing the effect of different manure sources; inorganic fertilizer (a combination of DAP and Urea), and organic sources (chicken manure and cow dung manure) on the proximate composition, amino acid and fatty acid profile of L. minor under culture conditions. Results indicated that L. minor cultured with chicken manure had significantly higher crude protein level (36.8%) (P < 0.05) and lower crude fat content (8.10%) compared to the ones cultured with inorganic fertilizer and cow dung manure. Essential amino acids proportion was 50% in L. minor cultured with inorganic fertilizer, 45.4% in chicken manure and 44.8% in cow dung manure with lysine and phenylalanine being the most abundant amino acids. The total polyunsaturated fatty acids (PUFA) were significantly higher (P < 0.05) in L. minor cultured using inorganic fertilizer (43.05 mg/100 g) with linoleic acid being the most dominant PUFA. The presence of high levels of amino acids and PUFA in the L. minor cultured with organic and inorganic fertilizer respectively indicates that it can provide quality protein and PUFA required for fish growth and well-being.