Nutritional values and bioactive components of under-utilised vegetables consumed by indigenous people in Malaysia.

Background: Diverse plants species in the forest remain under-utilised and they are mainly consumed only by local people. However, increasing issues in food security prompted the present study, which explores the nutritional and antioxidant aspects of Malaysian under-utilised vegetables. The studied vegetables were Paku Nyai (Stenochlaena palustris), Cemperai (Champereia manillana), Maman Pasir (Cleome viscose), Dudung (Erechtites valerianifolia) and Semambuk (Ardisia pendula).

Results: Overall, these vegetables exhibited a low proximal content but they were high in vitamin C [7.07-1263 mg kg(-1) edible fresh sample (EFS)] and β-carotene content (18.4-43.9 mg kg(-1) kg(-1) EFS). Cemperai had the highest calcium content (565 mg kg(-1) EFS), whereas Semambuk had the highest total phenolic content [28.21 g gallic acid equivalents kg(-1) edible dried sample (EDS)] and antioxidant activity (86.1%) measured using β-carotene bleaching assay. Maman Pasir contained the highest total flavonoid content (39.99 g CE kg(-1) EDS) and 1,1-diphenyl-2-picryl hydrazyl radical scavenging activity (82.2%). The extracts of these vegetables had significantly prevented the oxidation of haemoglobin and low-density lipoprotein, which yielded a reduced production of malondialdehyde.

Conclusion: Semambuk and Maman Pasir are potent to be used as new food and functional food sources as they are rich in nutrients and antioxidants.