Biotechnology Club

Unfortunately I have kept nothing from my MSc – two years of chopping up plants, extracting them with solvents and endless gravity silica chromatography columns broken up with the occassional acetylation or excursion to photograph wax crystals on leaves or do GC-MS of oils.

The two plants indigenous to South Africa that I looked at were Dioscorea dregeana (a type of yam used medicinally rather than for food) and Avonia rhodesica a tiny succulent. Both of them are used for narcotic purposes (though the yam was used for many other things as well), though I certainly did not find anything terribly exciting in either of them.

A compound that was in every single extract that I made was beta-sitosterol.

This compound was isolated so frequently in our laboratory that the nmr technician claimed that he was able to identify it from the raw NMR data (i.e. before Fourier transformation).

From leafy extracts we would also isolate a black compound which sometimes seemed to have a death grip to glass. NMR spectra showed what looked like a series of aldehyde groups. These would be terribly excting to the naive researcher, but it would turn out to (just) be one of the chlorophylls (the aromatic hydrogens are shifted out there because the porphyrin moiety is very aromatic – is that a meaningful statement?). Don’t get me wrong: chlorophylls are very interesting molecules, they just aren’t new and publishable from a Natural Product Chemistry point of view.