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Sorghum is one of the staple food crops in Tigray, northern Ethiopia. Despite this, limited research attention was given to the nutritional and antinutritional profiling of sorghum. Thus, this research was initiated to profile and evaluate the variabilities in protein, starch, minerals, flavonoid, tannin, and antioxidant activities among sorghum landraces of Tigray, northern Ethiopia. Protein and starch were analyzed using an infrared spectrophotometer, whereas mineral elements were estimated using an atomic absorption spectrophotometer. Antioxidant activity was analyzed using DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging, ferric-reducing antioxidant power, and phosphomolybdenum assays. The result revealed significant variation among the landraces for all the evaluated parameters. Protein and starch contents ranged from 6.21 to 18% and 33.42 to 78.30%, respectively. Wider variations were observed for Fe (32–101), Zn (16.9–42.98), Cu (1.48–5.25), Mn (9.21–20.23), and Cr (0–1.5) as measured in mg/100 g. The variabilities were high for total flavonoid (0–665 mg CE/g) and tannin (0.18–7.5 mgCE/100 g). DPPH (EC50 = 29.09–818.37 µg/mL), ferric reducing antioxidant power (17.85–334.81 mgAAE/g), and total antioxidant activity (1.71–63.88 mgBHTE/g) were also highly variable among the samples. The relationship between seed color and phenolics, as well as antioxidant activities, are discussed. Multivariate analysis revealed that the landraces were clustered into four distinct groups. The rich genetic diversity in the nutritional and antinutritional attributes may be an opportunity for breeding for grain quality improvements of sorghum that, in turn, helps in addressing malnutrition.

This study evaluated the genotype by environment interactions in the yield and nutraceutical traits of the orange-fleshed sweet potato (OFSP) storage root in different agro-climatic zones of northern Ethiopia. Five OFSP genotypes were cultivated at three different locations following a randomized complete block design, and the yield, dry matter, beta-carotene, flavonoids, polyphenols, soluble sugars, starch, soluble proteins, and free radical scavenging activity were measured in the storage root. The results showed consistent variations in the nutritional traits of the OFSP storage root depending on both the genotype and the location, as well as on their interaction. Ininda, Gloria, and Amelia were the genotypes that provided the higher yield and dry matter, as well as the higher content of starch and beta-carotene; they also showed a high antioxidant power. These findings suggest that the studied genotypes have the potential to alleviate vitamin A deficiency. This study demonstrated a high possibility of sweet potato production for storage root yield in arid agro-climate regions with limited production inputs. Moreover, the results suggest that it is possible to enhance the yield, dry matter content, beta-carotene, starch, and polyphenols of the OFSP storage root through genotype selection.

This study investigated the influence of the agro-climatic environment of Northern Ethiopia on the content of essential mineral elements of selected orange-fleshed sweetpotato genotypes, the potential contribution of each genotype’s essential mineral elements to the recommended dietary allowance, and the potential risk to human health from the accumulation of potentially toxic elements in the tuberous roots of the studied genotypes. The results showed consistent interspecific variations in the content of essential mineral elements among the studied orange-fleshed sweetpotato genotypes, as well as important intraspecific differences, which could depend on the variations in soil mineral and organic matter content, rainfall, temperature, as well as interactions between genotype and environment. The investigated genotypes, especially Kulfo, Ininda, Gloria, and Amelia, can provide an amount of several essential mineral elements high enough to meet 100% of the recommended dietary allowance for all age groups ≤8 years. The mean content of potentially toxic elements in tuberous roots and their daily intake values were within the recommended permissible levels; likewise, no health risk was associated with the consumption of these genotypes for Cr, As, and Pb. However, Al, Cd, Cu, Fe, Mn, and Ni is > 1, consumption imposes health risks based on daily accumulation.