Biomass Production of Water-Meal (Wolffia globosa) and Its Chemical Composition and Amino Acid Profiles when Grown with Chemical Fertilizer in an Out-door Polyethylene (PE) Tank Cultivation System

Water-meal (Wolffia globosa) was cultivated with NPK (15:15:15) fertilizer under three treatments with four replicates. The treatments consisted of NPK fertilizer applications at three different levels: 16 g/tank (CF1), 26 g/tank (CF2), and 36 g/tank (CF3), which were applied weekly. The water-meal was grown for 35 days, the biomass production was assessed, and the treatment with the highest mass production was harvested in order to determine the chemical composition and the amino acid profiles. The results showed that water-meal cultivated with NPK fertilizer at the rate of 26 g/tank (CF2) had exhibited the highest biomass production. There was a significant difference (P<0.05) compared to the CF1 treatment, while no significant difference (P0.05) was found when compared to the CF3 treatment. The water-meal that had been cultivated with the CF2 treatment exhibited high protein content (40.64±2.13%) and rich amino acid profiles. It contained 17 types of amino acid profiles, with 9 essential amino acids (EAA), and 8 non-essential amino acids (NEAA). Glutamic acid was the major amino acid, while leucine and lysine were the most abundant EAA. Our findings indicated that this cultivation system can be used to produce highly nutritious water-meal biomass for human consumption or animal feed.