Evaluation of Minerals, Phytochemical Compounds and Antioxidant Activity of Mexican, Central American, and African Green Leafy Vegetables

Abstract

The green leafy vegetables Cnidoscolus aconitifolius and Crotalaria longirostrata are native to Mexico and Central America, while Solanum scabrum and Gynandropsis gynandra are native to Africa. They are consumed in both rural and urban areas in those places as a main food, food ingredient or traditional medicine. Currently, there is limited information about their nutritional and phytochemical composition. Therefore, mineral, vitamin C, phenolic and flavonoid concentration, and antioxidant activity were evaluated in multiple accessions of these leafy vegetables, and their mineral and vitamin C contribution per serving was calculated. The concentrations of Ca, K, Mg and P in these leafy vegetables were 0.82-2.32, 1.61-7.29, 0.61-1.48 and 0.27-1.44 mg/g fresh weight (FW), respectively. The flavonoid concentration in S. scabrum accessions was up to 1413 μg catechin equivalents/g FW, while the highest antioxidant activities were obtained in C. longirostrata accessions (52-60 μmol Trolox equivalents/g FW). According to guidelines established by the US Food and Drug Administration, a serving size (30 g FW) of C. longirostrata would be considered an excellent source of Mo (20 % or more of the daily value), and a serving of any of these green leafy vegetables would be an excellent source of vitamin C. Considering the importance of the minerals, phytochemicals and antioxidants in human health and their presence in these indigenous green leafy vegetables, efforts to promote their consumption should be implemented.

Genetic diversity and association mapping of mineral element concentrations in spinach leaves

“…There is a growing interest in the mineral and phytochemical composition of foods and diets, and especially in leafy vegetables. Recent studies with Mexican, Central American, and African green leafy vegetables, including Cnidoscolus aconitifolius , Crotalaria longirostrata , Solanum scabrum , Gynandropsis gyandra , and several leafy Amaranthus species, have highlighted the contributions that these vegetables can provide to one’s daily intake of essential nutrients and health-beneficial compounds [ 44 , 45 ].…”

A comparison of the phenolic profile and antioxidant activity of different Cichorium spinosum L. ecotypes

“…Fruit and vegetables are considered a valuable source of phytonutrients and bioactive compounds, and according to various studies their high intake could reduce the risk of many diseases, such as cancer, diabetes and heart disease, and generally improves overall physical condition and health . Moreover, wild edible greens, including many species of the Asteraceae family, are important ingredients of the so‐called Mediterranean diet, owing to their high nutritional value and bioactive compound content .…”

African Nightshade (Solanum scabrum Mill.): Impact of Cultivation and Plant Processing on Its Health Promoting Potential as Determined in a Human Liver Cell Model

“…), locally known as mnavu in Swahili language, is widely used in West, Central and East Africa where it is cultivated as leafy vegetable [ 1 ]. The leaves are rich in nutrients, especially proteins, iron, ascorbic acid and riboflavin [ 2 , 3 ] which makes it a very important nutritional source for poor people. During the last years, a rising trend in the use of this crop can be observed as local people become aware of its proclaimed health benefits.…”

“…During the last years, a rising trend in the use of this crop can be observed as local people become aware of its proclaimed health benefits. A variety of health promoting, bioactive phytochemicals such as phenolic compounds, carotenoids and chlorophylls [ 2 , 3 ] have been identified recently in S. scabrum , which could be the reason for its gained popularity in the urban areas but also help explain its long use in traditional medicine. However, it is still unclear how these contribute to human nutrition and health, since scientific evidence on the health promoting activities of S. cabrum is scarce.…”