Phytochemical Analysis and Characterization of Corn Silk (Zea mays, G5417)

Abstract

Corn silk has long been thought of as a waste product; however, due to its numerous therapeutic attributes, it has remarkably gained popularity in Asian and African countries. Therefore, this study aimed to assess the bioactivity of dried corn silk powder (Zea mays, G5417) in terms of its physic-ochemical and bio-functional characteristics. The protein (15.29 ± 1.23) and ash (5.29 ± 0.29) contents in the corn silk powder were found to be high. The high phenolic content (94.10 ± 0.26 mg GAE/g) and flavonoid content (163.93 ± 0.83 mg QE/100 g) are responsible for its high antioxidant activity. The corn silk powder showed 45.40 ± 0.92% FRSA, 75.25 ± 0.59 TEAC mg/gdw of ABTS, and 86.77 ± 0.88% of FRAP. FT-IR spectroscopy revealed stretching, bending, and vibrations of abundantly present polysaccharides and protein functional groups. Moreover, the DSC thermograph revealed the exothermic reactions at on-set temperature (Tonset) = 21.9◦C and end temperature (Tendset) = 102.80◦C, and exothermic reactions at on-set temperature (Tonset) = 252.02◦C, end temperature (Tendset) = 296.80◦C, and denaturation peak temperature (Tpeak) = 277.48◦C, whereas XRD (2θ = 21.5◦) confirmed the amorphous nature of the corn silk powder. Therefore, due to the potential bioactivity and thermal stability, dry corn silk powder can be scaled up at an industrial level.