Levels Of Selected Macronutrients In Varieties Of Pumpkin (Cucurbita Spp) Grown In Four Selected Districts In Lake Victoria Basin

ABSTRACT

Lake Victoria Basin is one of the regions in sub-Sahara Africa which is densely populated and majority of the inhabitants are poor economically. Cases of diseases related to nutrient deficiency, child mortality, high HIV and AIDS have increased in the recent years due to malnutrition and undernourishment as the cost of basic foods have been on the rise. One way of reducing malnutrition is increased consumption of indigenous fruits and vegetables which offer variety of nutrients. The region has various indigenous foods not commonly consumed among them being pumpkins. Studies on pumpkin production, utilization and the nutritional content involving micronutrients have shown that different varieties of pumpkins contain different levels of nutrients. The need to promote varieties with higher levels of nutrients requires that levels are known. This study sought to determine varieties of pumpkins grown and the levels of selected macronutrients- proteins, carbohydrates, lipids, potassium, sodium, calcium, magnesium and phosphorus from Gucha & Busia in Kenya, Jinja in Uganda and Tarime in Tanzania. Identification of farmers was done through snowball (chain/referral) sampling method to obtain the pumpkin fruits. The levels of proteins were determined using kjeldahl method, carbohydrates using athrone method, lipids using soxhlet extraction, sodium and potassium using flame atomic emission spectroscopy, calcium and magnesium using flame atomic absorption spectroscopy and phosphorus using UV-visible spectrophotometry. Calibration curves of standards gave R2 > 0.995 which were used to determine the concentrations. Samples of six pumpkin varieties identified namely banana, carnival squash, crown prince, green kabacha, butternut and bottle guard were collected for macronutrient analysis. The level of proteins in the fruit flesh was 2.525 ± 0.620 g per 100g sample while in seeds was 34.882 ± 1.805 g, carbohydrates 7.604 ± 1.128 g in the fruit flesh and 3.118 ± 1.054 g in seeds, lipids in fruit flesh was 1.737 ± 1.031 g and 40.581 ± 6.543 g in seeds, phosphorus was 29.439 ± 2.371 ppm in the fruit flesh and 702.468 ± 6.910 ppm in seeds, potassium was 326.698 ± 20.73 ppm in the fruit flesh and 83.981 ± 621 ppm in seeds, sodium was 90.034 ± 14.23 ppm in the fruit flesh and 36.061 ± 4.24 ppm in seeds, magnesium was 21.144 ± 3.721 ppm in the fruit flesh and 57.261 ± 2.537 ppm in seeds, and finally, calcium was 64.654 ± 4.613 ppm in the fruit flesh and 99.659 ± 8.731 ppm in seeds. The levels of these nutrients varied significantly with variety and crown prince was superior over the others which support the view that pumpkins can be used to supplement nutrient availability to the inhabitants if grown.