Call edition 2012
A new edition of the Prize of the Belgian Development Cooperation has been launched. This call is open until March 31st, 2011. You can read in the regulations whether you comply with the criteria for participation.
The Master's thesis of Wael El-Sayed is a carefully executed and beautifully presented study of the biologically active polyphenolic compounds in the local cultivar of the cotton plant (Gossypium barbadense L. var. Giza 86). Cotton is one of the most economically important cultivated plants in Egypt, as well as in many developing countries.
This species contains the substance gossypol, which has been extensively studied and is known from the literature for its potential male antifertility properties. However, it also shows a number of toxic effects, in part due to its metabolism in the body.
Major contributions of this work are:
(1) the thorough chemical and histochemical characterisation of the polyphenolic compounds (histochemistry is the technique used to detect the presence of the compound in the plant organs by microscopic observation of e.g. coloured derivatives)
(2) the adaptation of a microbial testing system - rather than expensive animal cell culture techniques- to evaluate the metabolism of gossypol
(3) most importantly, the development of three simple, inexpensive and readily available bench-top methods to assess the properties of gossypol and its metabolites. These assays are based on the inhibition of cell division in onion root tips, and of growth of crown gall tumors on potato slices, and on their lethality on brine shrimps, which are widely available and easily kept in culture.
The results of these tests confirmed that gossypol and derivatives are toxic for cells, interfere with cell division and may have potential antitumor activity. However, the author demonstrated that they are enclosed in special cellular compartments, so that they do not harm the growth of the cotton plant itself. Some of the flavonoid compounds isolated also display pronounced antioxidant properties.
These findings may help to develop ways for research and use of other inexpensive and abundant bioactive substances in the pharmaceutical industry. More importantly, the experience gained from these simple bioassay systems on the cotton plant may be readily adapted to investigate other potentially useful plant species in developing countries, with most often limited laboratory facilities.
report by Prof. Dr. Wilfried Rombauts, Department of biochemistry, Campus Gasthuisberg, Katholieke Universiteit Leuven, Belgium