Evaluación del potencial antioxidante y calidad nutricional de Portulaca Oleracea L. Inoculada con Bacillus Subtilis y micorrizas arbusculares nativas en un sistema hidropónico vertical

Abstract

The degradation of agricultural soils, water scarcity, and increased abiotic stress associated with salinity have driven the search for sustainable alternatives for plant production. In this context, Portulaca oleracea L. stands out for its high tolerance to adverse conditions and its high nutritional and antioxidant value. The objective of this study was to evaluate the antioxidant potential and nutritional quality of P. oleracea inoculated with Bacillus subtilis and native arbuscular mycorrhizal fungi, grown in a vertical hydroponic system under drinking water and seawater conditions. A completely randomized block design was used, considering two blocks defined by water type and four treatments: control, inoculation with B. subtilis, inoculation with AMF, and co-inoculation. Agronomic parameters such as height, leaf area, and chlorophyll content were evaluated, as well as antioxidant capacity in leaves and stems using the DPPH assay and macronutrient content using ICP-OES spectrometry. The results showed higher antioxidant activity in stems, with the control treatment with saline water standing out, suggesting that saline stress stimulates endogenous antioxidant mechanisms. The inoculated treatments did not outperform the control, indicating a possible mitigating role in oxidative stress. Potassium was the predominant macronutrient, followed by magnesium, while calcium was not quantified due to analytical oversaturation. Statistical analysis showed significant differences in leaf area, where co-inoculation favored vegetative development under drinking water conditions, confirming the high potential of P. oleracea as a functional crop in sustainable hydroponic systems.