Composition de la poudre des feuilles sèches de moringa oleifera dans trois régions du Niger

Abstract

In Niger, the acute and chronic malnutrition constitutes a public health problem among children aged from six to fifty-nine months. The use of local foods was identified in the national protocol of malnutrition management as an alternative for ready to use therapeutic foods that are currently used. Among these local foods, the powder of dried leaves of Moringa oleifera was analyzed in order to know the composition of the powder of dried leaves of Moringa oleifera produced in Niger compared to the available data. To achieve this, four samples from the three main Moringa production regions in Niger namely Tillabéri, Niamey both located in the river basin and southern Maradi of the Sahel-Sudanese zone, were analyzed. The chromatographic analysis hasbeen made in the laboratory of the International Crops Research Institute for the Semi- Arid Tropics. The nitrogen extraction technique was done using H₂SO₄ digestion + salicylic acid + H₂O₂ and selenium. It was measured using the calorimetry auto analyzer, based the Bertholet reaction. Total phosphorous, iron, zinc, potassium, calcium, magnesium, sodium and copper was also extracted, using the same method. Phosphorus was measured by calorimetry using the method of molybdo-phosphate reduced to ascorbic acid. The other elements were measured using atomic spectroscopy absorption. The results correspond to the average of two parallel tests. Five standards enabled to make the calibration and a control sample was analyzed in the same conditions. The test is valid if the regression is about 0,9950 - 0,9999. The powder of dried leaves of Moringa produced in Niger turned out be rich in proteins with an average of 24, 8 % (Confidence Interval at 95%: 19, 34-30, 24) with values going from 21,58% in Tillabéri to 28,72% in Niamey and in micronutrients. According to regions, the composition varies for iron between 51,9 and 55,12 mg/100g, 0,45 and 1,58 mg/100g for zinc, 1192,5and 1957,5 mg/100g for calcium, 414,37 and 714,37 mg/100g for magnesium,1587 and 2037 mg/100g for potassium, 207,75 and 326,25 mg/100g for sodium, 32 and 61 mg/100g for phosphorus. These results are close to those revealed by earlier studies.

Key words: Moringa oleifera, composition, powder, dry, leaves, different, regions, Niger