Conservación y estandarización de extractos antioxidantes de accesiones silvestres: una estrategia en el tratamiento de cáncer colorrectal empleando Amaranthus blitoides, Amaranthus hypochondriacus y Beta macrocarpa

Germplasm Banks play a crucial role in plant genetic diversity conservation. Among them, BGV-UPM was the first Germplasm Bank dedicated to wild crops from crucifer family. Nowadays, 1112 accessions from BGV-UPM are in suboptimal conservation conditions, resulting in an unpredictable viability. Moreover, some of these accessions (Amaranthus hypochondriacus, Amaranthus blitoides and Beta macrocarpa) are of great interest to health research due to the presence of secondary metabolites. Hypotheses for secondary metabolites include a potential antioxidant activity as well as an anticancer activity. This work aims to start an accession rescue program; obtain and standardize extracts from A. hypochondriacus, A. blitoides and B. macrocarpa with antioxidant capacity; and evaluate the effect of these extracts on the cell viability od the DLD-1 colorectal cancer cell line. Here we show that A. hypochondriacus is the most viable accession (90%) of the three studied. Also, the maximum antioxidant capacity is obtained when 70% methanol is used in comparison to water, absolute methanol, cyclohexane and ethyl acetate. Extracts from A. hypochondriacus and A. blitoides show a similar IC50 for antioxidant activity (48±4-55±3 and 55±9-69±4 μmol TE/g DW respectively) whereas B. macrocarpa extract present 31±3-41±3 μmol TE/g DW. Compared to previous studies there are strong differences between the antioxidant capacity of the accessions. It is mainly because secondary metabolites synthesis depends on biotic and abiotic stresses. Additionally, A. blitoides show the smallest IC50 (0.19±0.03 mg extract/mL) against DLD-1 cell line. We identify that the range of action these extracts are 0,195- 3,125; 7,81∗10−3-0,625; and 0,313-25 mg/mL for A. hypochondriacus, A. blitoides and B. macrocarpa respectively. We believe that these results are a direct consequence of secondary metabolites such as betalains and saponins, but further research is needed. We anticipate our work to be a starting point for more detailed experiments about the characterization of the secondary metabolites present in the extracts as well as the molecular mechanisms in which these compounds are involved. Plus, our work has stablished the foundation for the rescue program of BGV-UPM.