Onion and ginger sprouting is associated with increased antioxidant activity.

Abstract

Aim: Although onion (Allium cepa) and ginger (Zinziber officinale) has been extensively studied for its health benefits, sprouted onion and ginger has received little attention. We hypothesized that sprouting onion and ginger would stimulate the production of various phytochemicals that improve health. Objectives: To investigate the effect of sprouting on the antioxidant activity of Allium cepa and Zinziber officinale and to compare the antioxidant activity of both Allium cepa and Zinziber officinale. Methods: Ethanolic extracts from onion and ginger sprouted for different periods had variable antioxidant activities were assessed with in vitro assays, including the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity assay and their total phenolic content for over a period of 15 days. Results: Extracts from onion sprouted for 7 days had the highest antioxidant activity, whereas extracts from raw onion had relatively low antioxidant activity. Similarly extracts from ginger sprouted for 15 days had the highest antioxidant activity, whereas extracts from raw ginger had relatively low antioxidant activity. Furthermore, sprouting changed the total phenolic content of both onion and ginger. Conclusion: Sprouting may be a useful way to improve the antioxidant potential of both onion and ginger.