Antimicrobial and Antioxidant Properties of Tropaeolum tuberosum Extracts from Ecuador

Abstract

Background and Objective: Nowadays, there is a growing interest in the use of natural antioxidants and antimicrobials for the treatment of diseases and this is where Andean tubers are playing an important role. Whereby, the objective of this work was to study the antimicrobial and antioxidant properties of Tropaeolum tuberosum extracts. Materials and Methods: In the present investigation, the extracts of 2 varieties of mashua were studied, white and yellow (Tropaeolum tuberosum), the extracts of the tuber were obtained by soxhlet and Supercritical Fluids (SCF) techniques, to these extracts were analyzed for their antioxidant activity by ABTS method and antimicrobial by disc-plate diffusion on 3 bacterial strains: Salmonella spp., Escherichia coli and Arcobacter spp. The extracts were characterized by mass coupled gas chromatography (GC-MS). Results: After the analysis of the antioxidant activity, the highest concentration presented the white mashua extract by supercritical fluids with a value of 6596.10 µmol trolox/g. In antimicrobial activity, the best inhibitory effect was evidenced on Salmonella strains with a halo diameter >8 mm, especially in the extract obtained from FSC, highlighting the white mashua (with an inhibition diameter of up to 20 mm). Through GC-MS, between 21 and 11 compounds were identified, where the compounds with the largest area were: Campesterol, $-Sitosterol, γ-Sitosterol, 4-Methoxybenzyl isothiocyanate and "-Tocopherol, which have been described as having antioxidant and antimicrobials effects. Conclusion: Consequently, it is concluded that the extracts can be used as a natural food additive