Elementary study on nutritional compositions of the green alga, Ulva lactuca in the South China Sea

In this paper,the contents of general nutritional compositions,amino acid composition of the protein,and of some inorganic elements of the green alga, Ulva lactuca in the South China Sea were studied. The results demonstrated that Ulva lactuca was is an alga rich in protein,cellulose,and ash. The essential amino acid contents of the protein in Ulva lactuca accounted for 41.2% of the total amino acid content,which indicated the alga was rich in essential amino acids.The contents of four kinds of flavor amino acids accounted for 41.5% of the total amino acid contents,so Ulva lactuca is a nutritional and delicious alga.The protein nutritive value in Ulva lactuca was estimated to be lower from first limit amino acid score (44.3),but to be higher from the second limit amino acid score(88.0),and the other essential amino acid scores were balanced,with the valine score being the highest.The contents of the five mineral elements in Ulva lactuca were higher than those in other algae,and the contents of iron (Fe)and magnesium(Mg)were very obvious,which indicated that the mineral contents of the alga were much richer.