Determination of Major Carotenoids in Processed Tropical Leafy Vegetables Indigenous to Africa


Tropical leafy-vegetables (n = 21) indigenous to Cameroon, Africa, were collected, processed, and analyzed for carotenoids by HPLC. The processing techniques used were oven drying; sun-drying; squeeze-washing and boiling; and a combination of boiling in alkaline salt and squeeze-washing. Carotenoids included lutein, α-carotene, zeaxanthin, β-cryptoxanthin, and β-carotene (all-trans, 13-cis, and 9-cis), which varied by species (P < 0.001). With the exception of P. purpureum and H. sabdarifa, lutein and β-carotene were the predominant carotenoids. In the oven dried vegetables, β-carotene was between 15% and 30% of total carotenoids and the values ranged from 7.46 ± 0.04 in T. indica to 39.86 ± 2.32 mg/100 g DW in V. oleifera. Lutein concentrations for these leafy vegetables ranged from 11.87 ± 0.7 in H. sabdarifa to 75.0 ± 3.6 mg/100 g DW in V. colorata and made up > 40% of total carotenoids. Traditional preparation and processing procedures led to significant losses of carotenoids and β-carotene was most affected during sun-drying with a maximum of 73.8% loss observed in A. acanthochiton.

Share and Cite:

V. Djuikwo, R. Ejoh, I. Gouado, C. Mbofung and S. Tanumihardjo, "Determination of Major Carotenoids in Processed Tropical Leafy Vegetables Indigenous to Africa," Food and Nutrition Sciences, Vol. 2 No. 8, 2011, pp. 793-802. doi: 10.4236/fns.2011.28109.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] R. A. Ejoh, A. N. Tanya and V. N. Djuikwo, C. M. Mbofung, “Effect of Processing and Preservation on the Iron and Vitamin A Levels of Some Species of Vernonia,” Sciences des Aliments, Vol. 25, No. 3, 2005, pp. 189-192. doi:10.3166/sda.25.185-192
[2] FAO/WHO, “Workshop on Fruit and Vegetables for Health. Fruit and Vegetables for Health,” Report of a Joint FAO/WHO Workshop, Kobe, 1-3 September 2004.
[3] S. A. Tanumihardjo and Z. Yang, “Epidemiology of Health Effects,” In: B. Caballero, L. Allen, A. Prentice, Eds., Encyclopedia of Human Nutrition, 2nd Edition, Elsevier Ltd., Oxford, 2005, pp. 339-345. doi:10.1016/B0-12-226694-3/00048-X
[4] M. Kimura and D. B. Rodriguez-Amaya, “Carotenoid Composition of Hydroponic Leafy Vegetables,” Journal of Agricultural Food Chemistry, Vol. 51, No. 9, 2003, pp. 2603-2607. doi:10.1021/jf020539b
[5] P. R. G. De Oliveira and D. B. Rodriquez-Amaya, “Processed and Prepared Corn Products as Sources of Lutein and Zeaxanthin: Compositional Variation in the Food Chain,” Journal of Food Science, Vol. 72, No. 1, 2007, pp. S79-S85. doi:10.1111/j.1750-3841.2006.00235.x
[6] D. S. McLauren and M. Frigg, “Practical Guide on Vitamin A in Health and Disease,” “Sight and Life Manual, Sight and Life Publication, 2002, p. 172.
[7] S. A. Tanumihardjo, “Food-Based Approaches for Ensu-Ring Adequate Vitamin A Nutrition,” Comprehensive Review of Food Science and Food Safety, Vol. 7, 2008, pp. 373-381.
[8] N. I. Krinsky, “Actions of Carotenoids in Biological Systems,” Annual Review of Nutrition, Vol. 13, 1993, pp. 561-587. doi:10.1146/
[9] A. Rodriguez-Bernaldo de Quiros and H. S. Costa, “Analysis of Carotenoids in Vegetable and Plasma Samples,” Journal of Food Composition and Analysis, Vol. 19, No. 2-3, 2006, pp. 97-111. doi:10.1016/j.jfca.2005.04.004
[10] Institute of Medicine, “Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc,” National Academy Press, Washington, D.C., 2001, pp. 65-126.
[11] WHO, “Global Prevalence of Vitamin A Deficiency in Populations at Risk 1995-2005,” WHO Global Database on Vitamin A Deficiency, 2010.
[12] K. J. Yeum and R. M. Russell, “Carotenoid Bioavailability and Bioconversion,” Annual Review of Nutrition, Vol. 22, 2002, pp. 483-504. doi:10.1146/annurev.nutr.22.010402.102834
[13] M. T. Ruel, “Can Food Based Strategies Help Reduce Vitamin A and Iron Deficiencies? A Review of Recent Evidence,” International Food Policy Research Institute, Washington, D.C., 2001, p. 79.
[14] K. Tontisrin, G. Nantel and L. Bhattacharjee, “Food-Based Strategies to Meet the Challenges of Micronutrient Malnutrition in the Developing World,” Proceedings of Nutrition Society, Vol. 61, No. 2, 2002, pp. 243-250. doi:10.1079/PNS2002155
[15] R. A. Ejoh, V. N. Djuikwo, I. Gouado and C. M. Mbofung, “Effect of the Method of Processing and Preservation on Some Quality Parameters of Three Non- Conventional Leafy Vegetables,” Pakistan Journal of Nutrition, Vol. 6, No. 2, 2007, pp. 128-133. doi:10.3923/pjn.2007.128.133
[16] K. Judprasong, S. Charoenkiatkul, P. Sungpuag, K. Vasanachitt and Y. Nakjamanong,, “Total and Soluble Oxalate Contents in Thai Vegetables, Cereal Grains and Legume Seeds and Their Changes after Cooking,” Journal of Food Composition and Analysis, Vol. 19, No. 4, 2006, pp. 340-347. doi:10.1016/j.jfca.2005.04.002
[17] U. Kidmosea, R. Y. Yang, S. H. Thilstedc, L. P. Christensena and K. Brand. “Content of Carotenoids in Commonly Consumed Asian Vegetables and Stability and Extractability during Frying,” Journal of Food Composition and Analysis, Vol. 19, No. 6-7, 2006, pp. 562-571. doi:10.1016/j.jfca.2006.01.011
[18] E. S. Tee and C. L. Lim, “Carotenoid Composition and Content of Malaysian Vegetables and Fruits by AOAC and HPLC Methods,” Food Chemistry, Vol. 41, 1991, No. pp. 309-339.
[19] E. P. Wasantwisut, V. Sungpuag, U. Chavasit, S. J. Chittchang and T. Viriyapanich, “Identifying and Recommending Vitamin A Rich Foods in Northeast Thailand,” In: E. Wasantwisut and G. A. Attig, Eds., Empowering Vitamin A Foods, Institute of Nutrition, Bangkok, 1995, pp. 69-90.
[20] M. M. Rahman, M. A. Wahed, D. Mahalanabis and R. B. Sack, “Preparing and Preserving Green Leafy Vegetables for Poor Communities in Bangladesh,” In: E. Wasantwisut and G. A. Attig, Eds., Empowering Vitamin A Foods. Institute of Nutrition, Bangkok, 1995, pp. 61-68.
[21] F. Khachik, M. B. Goli, G. R. Beecher, J. Holden, W. R. Lusby, M. D. Tenorio and M. R. Barrera, “Effect of Food Pre- Paration on Qualitative and Quantitative Distribution of Major Carotenoid Constituents of Tomatoes and Several Green Vegetables,” Journal of Agricultural Food Chemistry, Vol. 40, No. 3, 1992, pp. 390-398. doi:10.1021/jf00015a006
[22] T. C. Mosha, R. D. Pace, S. Adeyeye, H. S. Laswai and K. Mtebe, “Effect of Traditional Processing Practices on the Content of Total Carotenoid, β-Carotene, α-Carotene and Vitamin A Activity of Selected Tanzanian Vegetables,” Plant Foods for Human Nutrition Vol. 50, No. 3, 1997, pp. 189-201. doi:10.1007/BF02436056
[23] M. A. Horvitz, P. W Simon and S. A. Tanumihardjo, “Lycopene and Beta-Carotene Are Bioavailable from Lycopene ‘Red’ Carrots in Humans,” European Journal of Clinical Nutrition, Vol. 58, 2004, pp. 803-811. doi:10.1038/sj.ejcn.1601880
[24] J. A. Howe and S. A. Tanumihardjo, “Evaluation of Analyticcal Methods for Carotenoid Extraction from Biofortified Maize (Zea mays sp.),” Journal of Agricultural Food Chemistry, Vol. 54, No. 21, 2006, pp. 7992-7797. doi:10.1021/jf062256f
[25] J. C. Bauerfeind, “Carotenoids as Colorants and Vitamin A Precursors,” Academic Press, Orlando, 1984, p. 883.
[26] WHO, “Control of Vitamin A Deficiency and Xerophthalmia,” World Health Organization, 1982.
[27] National Research Council, “Recommended Dietary Allowances,” 10th Edition, National Academy Press, Washington, D.C., 1989.
[28] B. Kandlakunta, A. Rajendran and L. Thingnganing, “Carotene Content of Some Common (Cereals, Pulses, Vegetables, Spices and Condiments) and Unconventional Sources of Plant Origin,” Food Chemistry, Vol. 106, No. 1, 2008, pp. 85-89. doi:10.1016/j.foodchem.2007.05.071
[29] F. X. Cunningham Jr., “Regulation of Carotenoid Synthesis and Accumulation in Plants,” Pure and Applied Chemistry, Vol. 74, No. 8, 2002, pp. 1409-1417. doi:10.1351/pac200274081409
[30] D. J. Hart and K. J. Scott, “Development and Evaluation of an HPLC Method for the Analysis of Carotenoids in Foods and the Measurement of the Carotenoid Content of Vegetables and Fruits Commonly Consumed in UK,” Food Chemistry, Vol. 54, No. 1, 1995, pp. 101-111. doi:10.1016/0308-8146(95)92669-B
[31] A. J. Speech, S. Speek-Saichua and W. H. P. Schreurs, “Total Carotenoid and β-Carotene Contents of Thai Vegetables and the Effect of Processing,” Food Chemistry, Vol. 27, No. 4, 1988, pp. 245-257. doi:10.1016/0308-8146(88)90010-6
[32] R. Lakshminarayana, M. Raju, T. P. Krishnakantha and V. Baskaran, “Determination of Major Carotenoids in a Few Indian Leafy Vegetables by High-Performance Liquid Chromatography,” Journal of Agricultural. Food Chemistry, Vol. 53, No. 8, 2005, pp. 2838-2842. doi:10.1021/jf0481711
[33] Y. S. Cho, K. J. Yeum, C. Y. Chen, G. Beretta, G. Tang, N. I. Krinsky, S. Yoon, Y. C. Lee-Kim, J. Blumberg and R. M. Russell. “Phytonutrients Affecting Hydrophilic and Lipophilic Antioxidant Activities in Fruits, Vegetables and Legumes,” Journal of Science of Food Agriculture, Vol. 87, No. 6, 2007, pp. 1096-1107. doi:10.1002/jsfa.2817
[34] L. Ryan, O. O’Connell, L. O’Sullivan, S. A. Aherne and N. M. O’Brien, “Micellarisation of Carotenoids from Raw and Cooked Vegetables,” Plant Foods for Human Nutrition, Vol. 63, No. 3, 2008, pp. 127-133. doi:10.1007/s11130-008-0081-0
[35] B. H. Chen and Y. Y. Chen, “Determination of Carotenoids and Chlorophylls in Water Convolvulus (Ipomea aquatica) by Liquid Chromatography,” Food Chemistry Vol. 45, No. 2, 1992, pp. 129-134. doi:10.1016/0308-8146(92)90023-U
[36] F. M. Clydesdale, C.-T. Ho, C. Y. Lee, N. I. Mondy and R. L. Shewfelt, “The Effects of Postharvest Treatment and Chemical Interactions on the Bioavailability of Ascorbic Acid, thiamin, Vitamin A, Carotenoids, and Minerals,” Critical Reviews in Food Science and Nutrition, Vol. 30, 1991, No. 6, pp. 599-638.
[37] M. I. Gomez, “Carotene content of Some Green Leafy Vegetables of Kenya and Effects of Dehydration and Storage on Carotene Retention,” Journal of Plant Foods, Vol. 3, 1981, pp. 231-244.
[38] C. A. Pesek and J. J. Warthesen, “Photodegradation of Carotenoids in a Vegetable Juice System,” Journal of Food Science, Vol. 52, No. 3, 1987, pp. 744-746. doi:10.1111/j.1365-2621.1987.tb06717.x
[39] A. K. Baloch, K. A. Buckle and R. A. Edwards, “Effect of Processing Variables on Quality of Dehydrated Carrot. II. Leaching Losses and Stability of Carrot during Dehydration and Storage,” Journal of Food Technology, Vol. 12, No. 3, 1977, pp. 295-307. doi:10.1111/j.1365-2621.1977.tb00110.x
[40] R. Aman, A. Schieber and R. Carle, “Effects of Heating and Illumination on Trans-cis Isomerization and Degradation of β-Carotene and Lutein in Isolated Spinach Chloroplasts,” Journal of Agriculture and Food Chemistry, Vol. 53, No. 24, 2005. pp. 9512-9518. doi:10.1021/jf050926w
[41] S. K. Thakkar, B. Maziya-Dixon, A. G. O. Dixon and M. L. Failla, “Carotene Micellarization during in Vitro Digestion and Uptake by Caco-2 Cells is Directly Proportional to β-Carotene Content in Different Genotypes of Cassava,” Journal of Nutrition, Vol. 137, 2007, pp. 2229-2233.
[42] L. A. Chandler and S. J. Schwartz, “Isomerization and Losses of Trans β-Carotene in Sweet Potatoes as Affected by Processing Treatment,” Journal of Agricultural Food Chemistry, Vol. 36, No. 1, 1988, pp. 129-133. doi:10.1021/jf00079a033
[43] J. P. Sweeney and A. C. Marsh, “Effect of Processing on Provitamin A in Vegetables,” Journal of American Dietetics Association, Vol. 59, 1971, pp. 238-243.
[44] P. Rajyalakshmi, K. Venkatalaxmi, K. Venkatalakshmamma, Y. Jyothsna, K. Balachandramanidevi and V. Suneetha, “Total Carotenoid and β-Carotene Contents of Forest Green Leafy Vegetables Consumed by Tribals of South India,” Plant Foods Human Nutrition, Vol. 56, No. 3, 2001, pp. 225-238. doi:10.1023/A:1011125232097

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.