Biostimulant effects of Moringa oleifera on growth and antioxidant activity in red amaranth (Amaranthus tricolor L.) microgreens

Universitas Aisyiyah Yogyakarta, Jl. Siliwangi (Ring Road Barat) No. 63, Nogotirto, Gamping, Sleman, Yogyakarta 55292, Indonesia

^* Corresponding author: dinar@unisayogya.ac.id

Abstract

The development of newfound functional foods is a key driver of innovation in the food industry, aiming to meet the growing demand and expectations of consumers for healthier options. Microgreens are gaining popularity as functional foods due to their high nutrient density and rich content of bioactive compounds or secondary metabolites. To optimize its growth and antioxidant content, natural additives such as Moringa oleifera leaf extract can be used. This study aimed to evaluate the antioxidant activity of red amaranth (Amaranthus tricolor L) microgreens after the application of MLE as a biostimulant. The red amaranth seeds were planted on rockwool where biostimulants can be easily integrated into plant growth. Furthermore, the relationship between used concentration and biostimulant potential of extracts was observed. To determine the antioxidant properties of all tested extracts, four different concentrations of MLE 0% w/v, 10% w/v, 15% w/v, and 20% w/v were used. The highest ability to scavenge DPPH radical was shown by the extract at the highest tested concentration of MLE 20% w/v. In the highest concentration, the ability to scavenge DPPH radical was on 47,78 ppm, which is categorized as a very strong antioxidant. These results indicate that red amaranth microgreen given the addition of MLE has a high inhibitory value of free radicals. Furthermore, the 20% w/v MLE concentration significantly enhanced plant growth, resulting in nearly a 50% increase in microgreen height, as well as in fresh and dry weight, compared to the control. Considering these findings, suggest that MLE is an effective natural additive for improving the nutritional value and growth performance of red amaranth microgreens.