Nutritional quality of protein in the leaves of eleven Asphodeline species (Liliaceae) from Turkey

Abstract

The nutritional quality of the protein in the leaves of 11 Asphodeline (Liliaceae) species was investigated by the determination of the amino acid composition and calculation of several nutritional parameters. The average protein content was 4.7% and ranged from 2.5% in Asphodeline damascena ssp. rugosa to 8.2% in A. turcica. The most abundant essential amino acids were Thr (5.7%), Val (6.0%), Ile (4.7%), and Trp (2.1%). The amino acid composition of Asphodeline peshmeniana was well equilibrated according to Food and Agriculture Organisation standards, but Lys and sulphur amino acids were at limiting concentrations in all the other taxa. Determination of the protein efficiency ratio and biological value revealed that the protein in the leaves of Asphodeline species is of high nutritional quality. Hence, the Asphodeline leaves that are typically used in Turkey for the preparation of salads, represent a good source of protein with high levels of several essential amino acids and a good nutritional value. Analysis of the similarity based on the amino acid composition indicated the existence of different clusters that are consistent with the taxonomical classification, area of distribution, and morphological similarities of the Asphodeline species.