Influence of germination on the bioactive compounds, antioxidant capacity and thermic characteristics of Phaseolus vulgaris L. and Cajanus Cajan seeds

Abstract

Aim: To evaluate the effect of germination on total phenols, antioxidant capacity, trace elements, and thermal behavior of the seeds of Pigeon peas (Cajanus cajan L.) and Chacha and Recline varieties of the common bean (Phaseolus vulgarisL.). Methodology: The evaluation of the total phenols was done using Folin Ciocalteu’s spectrophotometric method; the antioxidant capacity through the DPPH y ABTSº+ radicals;the macro and microelements using the spectrophotometric optical emission coupled inductively with plasma method ICP-OES; and the thermic behavior through differential scanning calorimetry (DSC). Results: The germination process influenced the total polyphenol content, antioxidant capacity, and macro and microelements in each specie that was studied. For example, for the Recline variety seedlings, the phenol content increased by 57.75% in comparison to the seed. The antioxidant capacity against DPPH and ABTS º+ was greater in the seedlings in the following order: Chaucha variety>Pigeon pea>Recline variety. For the seeds, the macro and micro-element content had the following order: K>Mg>Ca>Na y Fe>Zn>Cu>Cr; for the seedlings, the greatest decrease was in K, Cr and the greatest increase was in Ca and Mn; the Na:K relationship was less than one. Finally, the thermic behavior, in reference to the gelatinization enthalpy (ΔH) was greater for the seed than the seedlings.