Seasonal variation in phytochemicals and nutraceutical potential of Begonia nelumbiifolia consumed in Puebla, México.

Abstract

Begonia nelumbiifolia is a traditional edible plant consumed and commercialized in the northern highlands of Puebla, México. The present study reports the seasonal variation inproximate analysis as well as organic acids, carotenoids and flavonoids content in both leaves and stalks of this plant. The stalks contained low concentrations of protein (~3%), fiber (~1.5%) and nitrogen free extract (~0.26%) during the time of study. Both organs showed contents of oxalic acid (91-103mg 100g-1 FW), ascorbic acid (50-65mg 100g-1 FW), lutein (1-2.5mg 100g-1 FW), β-carotene (1-3mg 100g-1 FW), quercetin (1.3-2.7mg 100g-1 DW) and rutin (0.5-1.7mg 100g-1 DW). Antioxidant activity against DPPH was observed by the stalk extracts from 30% methanol (IC50, 0.21-0.37mgL-1), pure methanol (IC50, 0.14-0.21mgL-1) and hexane: acetone (IC50, 0.77-1.21mgL-1). In vitro anti-HMG-CoA reductase (IC50, 0.07-0.36mgL-1) and anti-alpha-glucosidase (IC50, 0.28-0.43mgL-1) activities were observed in extracts from the edible stalks from pure methanol and 30% methanol. The leaf extracts from 30% methanol inhibited the growth of Pseudomonas syringae pv. tabaci TBR2004 (MIC, 254µgmL-1), P. syringae pv. tomato DC3000 (MIC, 423µgmL-1), P. syringae pv. glycinea (MIC, 605µgmL-1) and Clavibacter michiganensis AB299158 (MIC, 162µgmL-1). B. nelumbiifolia contained valuable phytochemicals associated to nutraceutical and biological properties. However, the consumption of the fresh stalks must be carefully considered because of the high oxalate content.