Effect of Foliar Application of Elicitors on the Growth and Nutraceutical Properties of Cape Gooseberry (Physalis peruviana L.) Plants

Cape gooseberry is a wild plant whose fruits and leaves have been widely used in traditional medicine due to its multiple beneficial health properties, which can be improved using elicitors during cultivation. The aim of this study was to evaluate the foliar application of chitosan (0, 10, 25 and 50 mg/L), hydrogen peroxide (0, 50, 100 and 150 µM) and sodium nitroprusside (0, 50, 100 and 150 µM) on cape gooseberry plants and its effect on the metabolite content, antioxidant capacity and digestive enzyme inhibitory activity of leaves. Results showed that foliar application of chitosan at 25 and 50 mg/L or sodium nitroprusside 100 and 150 µM during cultivation of cape gooseberry significantly improved the phenolic compounds, flavonoids, proline, and total chlorophyll contents of methanolic extracts of leaves, enhancing its antioxidant capacity, as well as α-amylase and α-glucosidase inhibitory activities, without affecting the growth of the plants, whereas hydrogen peroxide 150 µM improved the flavonoid content and pancreatic lipase inhibitory activity, however, this treatment decreased the proline content of leaves. Therefore, elicitors as chitosan and sodium nitroprusside, applied at low concentrations during growth of plants, could be considered as a tool to improve the nutraceutical potential of cape gooseberry leaves.