Abstract:
The protein content and amino acid profile of Anchote (Coccinia abyssinica) leaves and tubers were determined from ten different accessions taken from Debre Zeit Agricultural
Research Center, Ethiopia. Crude protein content was determined by Kjeldahl method and
amino acid profile was analyzed using performic acid oxidation and acid hydrolysis by
ninhydrin-derivatized analysis with amino acid analyzer. Crude protein content of Anchote
tuber ranged from 10.70% ± 0.26% to 13.72% ± 0.10%, whereas the crude protein content
in leaves were ranged between 30.38 ± 0.01% (“240407-1”) and 35.42 ± 0.05% (“223109-
1”). Total amino acid content ranged from 45.12 to 62.89 and 67.31 to 75.69 g/100 g protein for tuber and leaf samples, respectively. The mean values of essential, conditionally
essential and nonessential amino acids were 37.22 & 36.79%; 28.62 & 24.10%; and 34.16
& 39.11% for tubers and leaves, respectively. Arginine in tubers and glutamic acid in leaves
ranked the highest of all amino acids; while the least dominant essential amino acid was
methionine in both parts. Among the essential amino acids, leucine was dominant in all accessions tested with values ranged from 3.12 to 5.32 g/100 g protein in tubers and from
5.15 to 5.65 g/100 g protein in leaves. In general, the average amino acid content was
higher in the leaves (71.08 g/100 g protein) compared to the tubers (51.11 g/100 g protein). The nutritional quality of Coccinia abyssinica leaves and tubers range as follows: total
essential amino acids (TEAA)/ total amino acids (TAA) (37.57 & 36.82%), TEAA/total nonessential amino acids (TNEAA) ratio (0.60 & 0.58), The predicted protein efficiency ratio
(P-PER) (1.22 & 1.80), Essential amino acid index (EAAI) (35.28 & 53.93%), Predicted biological value (P-BV) (26.76 & 47.09%), Nutritional index (4.11 & 17.71%), and Amino acid
score (73 & 108) for tuber and leaf sample, respectively. A significant variability was observed in protein and amino acid profile among accessions and plant parts, and the leaf part
were found to be richer in protein content and associated nutritional quality.
