Biochemical characterisation of soybean germplasms with respect to bioavailable iron and zinc, vitamin A and crude protein

Abstract

Soybean germplasms were assessed for bioavailable zinc (Zn) and iron (Fe), vitamin A and crude protein using standard methods. Thirty soybean germplasms were investigated. Results were analysed using analysis of variance (ANOVA) and showed statistically significant differences in their Zn, Fe and vitamin A concentrations, as well as in crude protein content (P < 0.05). The Zn content ranged from 5.74 ± 0.04 to 18.15 ± 0.05 mg/100 g. TGX 1987-62F had the highest amount of Zn (18.15 ± 0.05 mg/100 g), while TGX 1485-1D had the least Zn concentration (5.74 ± 0.04 mg/100 g). The concentration of the Fe ranged from 6.65 ± 0.05 to 11.58 ± 0.05 mg/100 g with TGX 1987-62F showing the highest (11.58 ± 0.05 mg/100 g) and TGX 1987-10F the least (6.65 ± 0.04 mg/100 g) Fe concentrations. Investigation of the vitamin A content showed that TGX 1951-4F had the highest (8.83 ± 0.03 mg/L), while TGX 1989-53F had the least (2.48 ± 0.01 mg/L) vitamin A levels. Crude protein content ranged from 35.40 ± 0.09 to 57.92 ± 0.02%. TGX 1989-11F (57.92 ± 0.02%) showed the highest crude protein content, while TGX 1990-55F showed the least crude protein content (35.40 ± 0.09%). The germplasm TGX 1987-62F consistently showed high levels of crude protein, Zn and Fe concentrations, but moderate levels of vitamin A, whereas TGX 1989-11F and TGX 1951-4F had the highest levels of crude protein and vitamin A, respectively. No direct correlation with earlier observed genetic and morphological variabilities were observed in terms of bioavailable Fe and Zn, vitamin A and crude protein levels in these soybean germplasms. These genotypes can be widely used in the food industry for the commercial production of high quality protein diet for both human and animal consumption, and can be recommended as good sources of the micronutrients Fe, Zn and vitamin A.   Key words: Soybean, diversity, micronutrients, crude protein, iron, zinc, vitamin A.