Estimation of total carotenoids and free radical scavenging activity of selected vegetables
Main Article Content
Abstract
Background: Vegetables are known for their rich carotenoid content responsible for their antioxidant properties.
Objectives: This study sought to estimate the total carotenoid content (TCC) in four edible Nigerian vegetables, compare their free radical scavenging activity (FRSA) and relate their TCC to their respective FRSA.
Methods: The method employed for extraction involved homogenization with ethanol using a blender. Estimation of the TCC was obtained by an equation derived from their Chlorophyll A and B contents from reading absorbances of homogenates at 470nm, 649nm and 665nm. FRSA of ethanolic homogenates on 2,2-diphenyl-1- picrylhydrazyl (DPPH) by decreased absorbance of 1mM DPPH on adding extracts was read at 517nm. The FRSA obtained by 0.2-1% concentrations done in triplicates was compared statistically (ANOVA Test, p<0.01). Mean Inhibitory concentration (IC50) value was obtained graphically via percentage inhibition/concentration curve.
Results: Capsicum annum had the highest TCC compared to the other vegetables. Carica papaya leaves exhibited a superior FRSA compared to other plants (p<0.0001). Results showed that there may be a direct relationship between TCC and FRSA. However, Carica papaya which had the highest FRSA did not show a high TCC. Hence, Carica papaya may possess other phytochemicals other than carotenoids responsible for its high FRSA.
Conclusion: This study shows that Carica papaya leaves had a high FRSA and antioxidant capacity due to the presence of carotenoids and other beneficial phytochemicals. This evidence supports the fact that it can be included into our diet as Africans.
Downloads
Article Details
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
References
Sofowora A (1993). Medicinal plant and Traditional medicine in Africa. 3rd Edn. Spectrum books, Ibadan, p12.
Caldecott T (2011). Food as Medicine: The theory and Practice of Food. PhytoAlchemy, New York, pp 11-12.
Pala FS and Gurkan H (2008).
Rietjens IM (2002). The pro-oxidant chemistry of the natural antioxidants, Vitamin C, Vitamin E, carotenoids and flavonoids. Environmental
Toxicology and Pharmacology, 11(3-4):321-33.
Badifu GIO, Akpapunam MA and Mgbemere VM (1995). The fate of beta-carotene in processed leaves of fluted pumpkin (Telfairia
occidentalis Hook.): A popular vegetable in Nigerian diet. Plant Foods for Human Nutrition, 48(2):141-147.
Maisarah AM, Amira BN, Asmah R and Fauziah O (2013). Antioxidant analysis of different parts of Carica papaya. International Food Research Journal, 20(3): 1043-1048.
Southon S and Faulks R (2003). Carotenoids in food: Bioavailability and functional benefits. In: Johnson I, Williamson G (Eds.), Chapter 7.
Phytochemical functional foods. Woodhead Publishing Limited, CRC Press, Cambridge, UK, pp. 107-127.
Mech-Nowak A, Świderski A, Kruczek M, Łuczak I and Kostecka-Gugała A (2012). Content of carotenoids in roots of seventeen cultivars of Daucus carota L. Acta Biochimica Polonica, 59(1):139–141.
Qian H and Nihorimbere V (2004).Antioxidant power of phytochemicals from Psidium guajava leaf. Journal of Zhejiang University Science, 5
(6): 676-683.
Dere S, Gunes T and Sivaci R (1998). Spectrophotometric Determination of Chlorophyll - A, B and Total Carotenoid Contents of Some Algae Species Using Different Solvents. Turkish Journal of Botany , 22: 13-17.
Lichtenthaler HK and Wellburn AR (1983). Determination of Total Carotenoids and Chlorophylls A and B of Leaf in Different
Solvents. Biochemical Society Transactions, 11:591-592. The role of free radicals in ethiopathogenesis of diseases. Advances in Molecular Biology, 1: 1-9.
Ayoola GA, Coker HAB, Adesegun SA, Adepoju Bello AA, Obaweya K, Ezennia EC and Atangbayila TO (2008). Phytochemical Screening and Antioxidant Activities of Some Selected Medicinal Plants used for Malaria. Tropical Journal of Pharmaceutical Research, 7 (3): 1019 - 1024
Sierzant K and Gabrielska J (2009). Estimation of antioxidative properties of the natural polyphenols in the oxidation process of model
liposome membranes. Proceedings of International Ph.D. Students Conference Faculty of Agronomy, Mendel University of Agriculture and Forestry, Brno, Czech Republic. ISBN: 978-80-7375-352-8.
Wall MM, Waddell CA and Bosland PW (2001).Variation in β-Carotene and Total Carotenoid content in Fruits of Capsicum. Horticultural Science , 36(4): 746-749.
Jaswir I, Noviendri D, Hasrini RF and Octavianti F (2011). Carotenoids: Sources, medicinal properties and their application in food and nutraceutical industry. Journal of Medicinal Plants Research, 5(33): 7119 – 7131.
Kasim LS, Olaleye KO, Oladosu IA, Aiyelaagbe OO and Flamin G (2014). Antioxidant and Cytotoxicity of Essential oils from Struchium
sparganophora (Linn) Ktze Asteraceae. Journal of Pharmaceutical Sciences and Pharmacy Practice, 10 (1): 12-15.
Aravind G, Bhowmik D, Duraivel S and Harish G (2013). Traditional and Medicinal Uses of Carica papaya. Journal of Medicinal Plants Studies, 1(1): 7-15.