Iodine Fortification Study of Some Common African Vegetables

Abstract

Iodine Deficiency Diseases (IDDs) occupy important positions in the health problems of developing countries. Salt Iodisation has been the common approach to solving these problems. However, apart from the problems of lack of compliance by salt manufacturers, and inculturation of the consumers, health conditions aggravated by high salt intake by humans have become increasingly relevant. These problems can be eliminated if the commonly produced and consumed plants are fortified with Iodine. The prospects are in the inclusion of Iodine-containing compounds in the inorganic fertilizers used by farmers. In this study, Potassium Iodide and Potassium Iodate were used as inoculants. Five different concentrations—0.1 M, 0.2 M, 0.3 M, 0.4 M, and 0.5 M of Potassium Iodide and Potassium Iodate solutions were used to inoculate the soils on which the following edible African plants were planted: Murraya koenigii; Ocimum gratissimum; Cucurbita pepo; Solanum nigrum; Amaranthus hybridus and Abelmoschus esclentus, Corchorous olitoruis, Solanum lycopersicum, Zingiber officinale, Telfairia occidentalis, Talinium triangulare, Solanum melongena. Controls were also planted. After 14 days, alkaline dry ash method was used to determine the Iodine concentrations in the plants. The results showed that Murraya koenigii showed the highest absorption of Iodine 6.90 mg/kg at 0.3 M using KI, followed by Amaranthus hybridus 6.40 mg/kg at 0.1 M. Solanum nigrum, Ocimum gratissimum and Zingiber officinale also showed good absorption. Other plants except Murraya koenigii, Ocimum gratissimum, Solanum nigrum and Zingiber officinale showed very low tolerance to KI absorption. The result also showed that Telfairia occidentalis showed the highest absorption of iodine 8.20 mg/kg at 0.2 M of KIO3 followed by Cucurbita pepo 6.40 mg/kg at also 0.2 M of KIO3. Murraya koenigii, Ocimum gratissimum, Solanum nigrum, Zingiber officinale also showed good absorption of KIO3. Some of the plants were not able to tolerate the absorption at higher concentration for both KI and KIO3. All the plants were poisoned at concentration of 0.5 M for both Ki and KIO3. Murraya koenigii, Ocimum gratissimum, Solanum nigrum, Zingiber officinale can be used in iodine biofortification using KI and KIO3 at concentration The overall result may be very significant, when it is considered that Iodine is a micronutrient, with a daily intake requirement of 100 - 150 μg/kg. It can be seen that there is hope in achieving this kind of biofortification.