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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 non-essential 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. [ABSTRACT FROM AUTHOR]

The effect of natural and lactic acid bacteria ( LAB) fermentation processes on metabolite changes in pastes of soybeans and soybean-maize blends was studied. Pastes composed of 100% soybeans, 90% soybeans and 10% maize, and 75% soybeans and 25% maize were naturally fermented ( NFP), and were fermented by lactic acid bacteria ( LFP). LAB fermentation processes were facilitated through back-slopping using a traditional fermented gruel, thobwa as an inoculum. Naturally fermented pastes were designated 100S, 90S, and 75S, while LFP were designated 100 SBS, 90 SBS, and 75 SBS. All samples, except 75 SBS, showed highest increase in soluble protein content at 48 h and this was highest in 100S (49%) followed by 90 SBS (15%), while increases in 100 SBS, 90S, and 75S were about 12%. Significant ( P < 0.05) increases in total amino acids throughout fermentation were attributed to cysteine in 100S and 90S; and methionine in 100S and 90 SBS. A 3.2% increase in sum of total amino acids was observed in 75 SBS at 72 h, while decreases up to 7.4% in 100 SBS at 48 and 72 h, 6.8% in 100S at 48 h and 4.7% in 75S at 72 h were observed. Increases in free amino acids throughout fermentation were observed in glutamate ( NFP and 75 SBS), GABA and alanine ( LFP). Lactic acid was 2.5- to 3.5-fold higher in LFP than in NFP, and other organic acids detected were acetate and succinate. Maltose levels were the highest among the reducing sugars and were two to four times higher in LFP than in NFP at the beginning of the fermentation, but at 72 h, only fructose levels were significantly ( P < 0.05) higher in LFP than in NFP. Enzyme activities were higher in LFP at 0 h, but at 72 h, the enzyme activities were higher in NFP. Both fermentation processes improved nutritional quality through increased protein and amino acid solubility and degradation of phytic acid (85% in NFP and 49% in LFP by 72 h). [ABSTRACT FROM AUTHOR]