Protein Extracts from Fish Head as Natural Fertilizer for Corn Plants

The amino acid composition in the hydrolysates of fish proves to be a most promising source of protein. Two extracts from fish by-products (P1, from the head and fins of sturgeon and P2, from the cartilage of sturgeon head and fins) were obtained as liquids that were dried at 40°C. Liquid extracts were characterized physico-chemically (dry matter 3.86% and 4.25%, protein content 1.44% and 3.25%), and particle size (247nm, 94% and 4148nm, 65% majority populations for P1 and P2) and zeta potential (-27.4mV and -15.8mV) were measured. The smaller particle size for the P1 extract led to its choice for treatments applied in the growth of corn seeds. Four samples of concentrations of 0.5%, 1%, and 1.5% and control concentrations were experimented, each on 25 corn seeds, observing the growth of plants over a period of 13 days. A 13% higher increase of the corn plants was obtained in the case of the sample treated with 1.5% fish protein extract, P1. Throughout the experiments, the P1 sample with 1.5% fish protein extract had higher increases than the control sample. These results suggest that extracts from the head by-products of sturgeon fish could be used in agriculture as a nutrient in the growth of corn plants.