Comparative Study of Mineral Composition of Selected Staple Green Leafy Vegetables in Nigeria

Abstract

Six varieties of green leafy vegetables, namely, Amaranthus hybridus, Corchorus olitorius, O. gratissimum, Talinum triangulare, Telfaria occidentalis and Vernonia amygdalina were estimated in their raw, steamed and boiled forms for their mineral compositions. The effect of two different cooking methods (steaming i.e. water blanching and boiling) on fresh leafy vegetables were also evaluated. The mineral contents of fresh leaves of the vegetables were determined using Energy Dispersive X-ray Fluorescence techniques (EDXRF). The results from EDXRF analysis of mineral contents of the six leafy vegetables revealed that fresh, steamed and boiled C. olitorius had the highest quantity of K (133.5, 131.5 and 91.2 mg/100 g) and Zn (28.9, 28.4 and 21.4 mg/100 g) respectively. The fresh, steamed and boiled T. occidentalis had the highest quantity of Ca (124.2, 122.2 and 80.3 mg/100 g), Na (102.2, 100.6 and 71.1 mg/100 g) and Mg (324.5, 319.2 and 225.5 mg/100 g) respectively, while the fresh, steamed and boiled A. hybridus had the highest quantity of Fe (48.6, 47.7 and 29.1 mg/100 g) respectively. The results of percentage loss of mineral composition revealed that almost 40 % of minerals in boiled vegetables was lost, while the amount lost in steamed vegetables was < 2 %. The results obtained from evaluation of sodium/potassium (Na/K) ratio showed that all fresh and steamed leafy vegetables have the same values but the boiled leafy vegetables gave different values. The results have shown that vegetables could serve a better source of some important minerals that can contribute qualitatively to the nutritional need of humans. Based on the results from the processing of vegetables, we suggest that the daily nutritional needs can better be acquired by consuming the steamed processed vegetables rather than consuming the boiled processed vegetables, which would also probably reduce high blood pressure diseases.

Proximate and Anti -Nutritional Properties of Four Forms ofthegenusBasella (Basellaceae) in South-western, Nigeria

“…The four forms of Basella vary signi cantly at p < 0.05. (15) Comparative studies of the protein contents of the four forms of Basella, vary signi cantly in their protein contents at p < 0.05. Although the protein contents of the vegetables studied were low, they contribute to protein intake in the diet even though the report of ( 15) noted that plants food that provide more than 12% of their calorie values from proteins are good sources of protein.…”

Effect of processing methods on the nutritional quality of Solanum aethiopicum and Colocasia esculenta leafy vegetables commonly consumed in Ebonyi State, Nigeria

“…Water is also the holding medium for electrolytes and all other ions throughout the human body, according to Mepha, Eboh, and Banigbo (36). Some of the changes in % moisture composition might be attributed to factors such as climate, soil species and type, growth circumstances, the application of natural or artificial manure, and the time period of study (1). On the contrary, Studies have implicated moisture content in deteriorative activities in vegetable and is used as a measure of stability and the susceptibility to microbial contamination (13).…”

“…A large percentage of undeveloped nations rely on starch-based foods as their primary source of energy as well as other nutrients. This act of relying on starchbased foods as the primary source of energy has contributed to other nutrient deficiencies and inadequacya leading cause of anemia among vulnerable populations, as acknowledged by the Food and Agricultural Organization (1). In Nigeria, the burden and incidence of anemia are high, especially for the vulnerable and disadvantaged population (pregnant women and children) in most rural communities (2).…”

An Assessment of trace metals in selected Leafy vegetables in Lagos state

“…Vegetables are considered important in the human diet as they contain essential nutrients namely minerals, vitamins, fibers and antioxidants which offers health benefits (Gupta et al, 2021). Their regular consumption either raw or cooked helps in the prevention and cure of many diseases such as diabetes, anaemia, hypertension and cardiovascular diseases (Adeniyi et al, 2018;Aslam et al, 2020). Vegetables take up metals and absorbed them into both their consumable and non-consumable parts (Guerra et al, 2012).…”

“…They are widely consumed in Nigeria together with other foods due to their nutritional value and for improving the quality of soups (Adeleke & Biodun, 2010). They are also proven useful for medicinal purposes (Ayoola et al, 2010;Adeniyi et al, 2018). They offer economic benefits as they are cheap, and a highly valuable source of important nutrients, especially for the population of developing countries.…”