Interdisciplinary Seminar:
Education for Sustainable development
Convener: Eliane Didier, France

Variations in Nimbin and Salannin Production from Neem (a zadirachta indica ) in relation to the ecological factors in Sudan
Intisar E. Elteraifi, International Member, Sudan

The neem tree is important to Sudanes agriculture as a source for safe and environmental friendly pesticides. Two triterpenoids from the neem seed kernel extracts, salannin and nimbin, have been quantified in this study using HPLC. Samples from ten different regions in Sudan had been analyzed over two successive seasons. Salannin was found to range from 1.594 mg/g to 3.023 mg/g and 1.045 mg/g to 2.82 mg/g in the first and second season respectively. Nimbin ranged from 1.389 mg/g to 2.114 mg/g and 1.048 mg/g to 2.561 to 2.561 mg/g in the two respective seasons. Significant inter and intra variations were observed among and between the ten regions in quantities of the two limonoids in both seasons. The rainfall affected Salannin, while nimbin was not affected by any of the meteorological factors studied. Although rainfall was found to be the most important factor on salannin content, the relative humidity and temperature were found to have no direct effect on both salannin and nimbin.

Overall, the results show great variation within and between regions in Sudan in salannin and nimbin content. Practical implications of these findings in plantations programs and use of the limonoids in the commercial bio-pesticides are discussed in this report.

Keywords: Azadirachta indica; neem; triterpenoids, salannin; nimbin; meteorological data; ecological variation; limonoids, Sudan.

Dr Intisar E. Elteraifi is an Assistant Professor and Head of the Environmental Sciences & Natural Resources Department, Faculty of Agricultural Sciences at the University of Gezira , where she was awarded her PhD for her thesis on Variability in growth, oil, and limonoids in neem (Azadirachta indica A. Juss) from different ecozones in Sudan in 2004.