Mohammad Khairul Alam*, Rumana Tuli, Mohammad Sharif Khan, Abu Tareq Mohammad Abdullah, Maksuda Khatun, Mohammad Akhtaruzzaman and Sheikh Nazrul Islam Pages 40 - 50 ( 11 )
Background: Polyphenolic compounds are known to provide health benefits and protect against degenerative chronic diseases. Utilization and identification of foods with a high content of these compounds are gaining greater attention nowadays.
Objective: The present study reports the total phenolic content (TPC), polyphenolic composition and antioxidant activity (DPPH, FRAP and TEAC) of 10 commonly consumed leafy vegetables growing in Bangladesh.
Materials and Methods: The samples were collected from different locations of Bangladesh and mixed together to ensure sample representativeness. Folin-Ciocalteu method was used for the analysis of TPC, and quantification of polyphenolic components was done by high-performance liquid chromatography (HPLC- DAD). Additionally, antioxidant activities of the selected vegetables were also analysed by utilizing DPPH, FRAP & TEAC.
Results and Discussion: TPC ranged from 23.64 ± 1.20 to 45.59 ± 3.04 mg gallic acid equivalent (GAE)/g freeze-dried sample (fds). The polyphenolic spectrum ranged from 0.30 ± 0.02 to 647.42 ± 147.12 mg/100 g fds; quantity and spectrum of which varied in the vegetables. Among the studied vegetables, Centella asiatica contained the highest amount of TPC (45.59 ± 3.04 mg GAE/g fds) and also exhibited high antioxidant capacities, as documented by DPPH, FRAP and TEAC assays. Moreover, Principal component analysis (PCA) of investigated variables clearly separated Centella asiatica from other samples.
Conclusion: Phenolic compounds being strong antioxidants reduce the risk of chronic diseases and the finding of this study would aware the people to take vegetables rich in phenolics. It would also fill up the data gap in the existing food composition table of Bangladesh.
Antioxidants, HPLC-DAD, leafy vegetables, polyphenolic profile, principal component analysis, total phenolic content.
Institute of Nutrition and Food Science, University of Dhaka, Dhaka-1000, Institute of Nutrition and Food Science, University of Dhaka, Dhaka-1000, Thayer school of Engineering, Dartmouth College, Hanover, New Hampshire 03755, Institute of Nutrition and Food Science, University of Dhaka, Dhaka-1000, Department of Botany, University of Dhaka, Dhaka- 1000, Institute of Nutrition and Food Science, University of Dhaka, Dhaka-1000, Institute of Nutrition and Food Science, University of Dhaka, Dhaka-1000