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Aflatoxicosis is a public health problem in Nigeria like other tropical and sub-tropical regions of the world. Control of aflatoxin contamination requires thorough risk assessment, monitoring, quality control and empirical data. This study assayed total aflatoxin levels, identified and quantified four aflatoxin types in five food commodities commonly consumed in the six geopolitical zones of Nigeria. The food materials: <em>Zea mays, Colocynthis citrullus, Capsicum frutescens, Irvingia gabonensis</em> and <em>Arachis hypogea</em> were obtained from Watt market in Calabar urban. ELISA method was used for total aflatoxin, HPLC for aflatoxin types, AOAC for moisture. All (100%) the samples were contaminated with aflatoxin. Contamination was highest in<em> Irvingia gabonensis</em> (63.40 ± 1.79 µg/kg) and least in <em>Zea mays</em> (3.20 ± 0.12 µg/kg) (p &lt; 0.05). Except for <em>Irvingia gabonensis</em> and <em>Colocynthis citrullus</em>, total aflatoxin was within safe intake level of the Nigerian regulatory authority (National Agency for Food and Drug Adminstration and Control {NAFDAC}). All four aflatoxin types occurred in <em>Irvingia gabonensis</em>, <em>Capsicum frutescens</em> and <em>Colocynthis citrullus</em>; none was detected in <em>Arachis hypogea</em>. AFB₁ contamination was highest in<em> Irvingia gabonensis</em> (11.71±0.10 µg/kg) followed by <em>Capsicum frutescens</em> (1.21 ± 0.01 µg/kg); AFB₂ ranged from 0.00 ± 0.00-2.43 ± 0.05 µg/kg, AFG₁0.00 ± 0.00-3.73 ± 0.04 µg/kg, and AFG₂ 0.00 ± 0.00-0.54 ± 0.01 µg/kg (p &lt; 0.05). Only<em> Irvingia gabonensis</em> exceeded the limit of AFB₁ specified by NAFDAC for human foods. Moisture content varied widely (3.23 ± 0.03%-10.37 ± 0.19%).<strong> </strong>The trend in the occurrence of aflatoxins in the food samples was directly proportional (r = 0.91) to their moisture contents. Food<strong> </strong>commodities sold in Calabar carry potential health hazard. Improved handling through food processing, preservation and storage can minimize aflatoxins in foodstuffs and ensure sustainable quality of food supply.

Aim: The aim of the study was to carry out a comparative analysis of the proximate, vitamin and mineral composition of the leaves of four selected tropical vegetable plants namely: Ocimum gratissimum, Piper guineense, Gongronema latifolium and Vernonia amygdalina. Methodology: Fresh leaves of each vegetable were washed and air dried at room temperature for two weeks. The dried leaves were pulverized using a mechanical grinder. Measured amounts were subjected to quantitative proximate, vitamin and mineral analysis. Results: For all four plants, carbohydrates was the major macronutrient constituents (range 49.61-64.09% dry wt.) followed by fats (15.06-29.43%), Protein (7.28-12.53%), ash (1.81-14.82%) and fiber (2.92-7.53%) in that order. G. latifolium had the highest carbohydrate (64.09±0.09% dry weight) and protein (12.53±0.10%) composition while V. amygdalina had the highest fat (29.43±0.03%) composition. Results of Ash analysis of the four leaves showed P. guineense to have the highest total mineral content (14.82±0.12% dry wt.) followed by V. amygdalina (10.75±0.01%), O. gratissimum (4.60±0.04%) and G. latifolium (1.81±0.01%) in that order. O. gratissimum and P. guineense had the highest composition of fiber (7.53±0.02% and 7.22±0.02% respectively) closely followed by G. latifolium (6.03±0.02%) and V. amygdalina (2.92±0.02%). Vitamin analysis revealed that leaves of the four vegetable plants contained high levels of vitamin C (range 18.1-43.4 mg/100 g) and appreciable quantities of vitamins A (0.3-1.2 mg/100 g) and E (0.67-0.9 mg/100 g). V. amygdalina leaf contained the highest concentration of vitamin C (43.4±0.01 mg/100 g) and A (1.2±0.9 mg/100 g) while O. gratissimum had the highest vitamin E content (0.9 mg/100 g). The mineral assay indicated that the leaves of the plants contain high levels of Magnesium (Mg)(3.6-24.8 mg/100 g), Phosphorus (P) (2.8-34.3 mg/100 g), Calcium (Ca) (12.1-19.0 mg/100 g) and copper (Cu) (5.8-18.5 mg/100 g) relative to their Zinc (Zn) (1.1-2.1 mg/100 g), Potassium (K) (2.1-6.9 mg/100 g)  and Sodium (Na) (4.3-8.1 mg/100 g) contents. Conclusion: In conclusion, these plants were shown to be rich in carbohydrates, proteins and fats, vitamins and minerals justifying their use in diets. That the plants were particularly rich in vitamins and mineral with antioxidant properties could explain the therapeutic uses of the various preparations of these leafy vegetables, in traditional medicine, for the treatment and management of diseases that have their etiology and pathophysiology in free radical generation and oxidative stress.

Aim: The nutritive value, proximate, vitamin and mineral compositions of seven commonly consumed vegetables in South-Southern Nigeria were determined. Methodology: Pods and leaves of vegetables were divided into two parts. One part was analyzed raw and the remaining part was cooked by boiling. The raw vegetable leaves and okro pods were separately washed and dried using a food dehydrator (40ºC) for 24hrs. After drying, it was milled into fine flour using an electric blender. The second part of the vegetables were processed by boiling using variable time, after boiling, they were separately drained and dried using a food dehydrator at a temperature of about 50ºC for 48 hrs. Chemical analyses were carried out using standard laboratory methods. Means and standard deviations were calculated using the statistical package for social science. The least significant difference (LSD) was accepted at P = .05 significance. Results: For the raw vegetables the results were as follows: Moisture 71.2 – 91.2%, ash 0.9- 2.9%, dietary fibre 9.2 – 13.1%, fat 0.3 -1.4%, protein 2.1 – 8.2%, available Carbohydrate 1.0 – 8.7%, phosphorus 8 -52 mg/100 g, potassium 263- 1152 mg/100 g, sodium 3-23 mg/100 g, calcium 183-815 mg/100 g, magnesium 67-217 mg/100 g, iron 0.26-1.27 mg/100 g, zinc 0.26-1.10 mg,  folate 3-13 mcg/100 g. The results of the boiled vegetables were: moisture 80.9– 93.8%, protein 1.7 – 3.2%, fat 0.2 – 0.5%, ash 0.5– 1.1%, dietary fibre 3.9 – 9.3%, available carbohydrate 3.8 – 9.9%, phosphorus 7 – 35 mg/100 g, Potassium 0.33 – 300 mg/100 g, sodium 0.3 – 20 mg/100 g, magnesium 45 – 132 mg/100 g, calcium 82 – 200 mg/100 g, iron 0.21 -0.60 mg/100 g, zinc 0.13 – 0.30mg/100g. Folate 3 – 6 mcg/100 g. The range of the percentage contributions of the vegetables that are consumed raw to the recommended nutrient intake or recommended dietary allowance of adults are as follows: protein 5-18%, fat 1-3%, carbohydrates 1-6%, dietary fibre 3-52%, iron 2-14%, zinc 6-36%, calcium 26 -116%, phosphorus 8-31%, sodium 0.3-1%, Potassium 8-32%, Magnesium 26-99%, Folate 3-4%. Conclusion: Boiling significantly reduced most nutrient studied. Bitter leaves are more nutrient dense than other studied vegetables. Knowing the food compositions of these vegetables will promote their use.

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