Jitterbugs

Peas, beans and some other plant seeds contain proteins, called globulins, which have been shown to act as a defence against insects and other herbivores. Coffee beans contain large amounts of globulins, so scientists in Brazil studied the beans to assess their potential for warding off insects.

Their study, published in the Journal of Agricultural and Food Chemistry,^{1 tested the proteins against cowpea weevil larva. Proteins from the seeds of two coffee species were characterized and isolated by gel filtration and reversed-phase chromatography, before being fed to the weevil larva. The coffee proteins killed up to half of the insects and significantly reduced the larval weight relative to the control group confirming the insecticidal effect.}

Next, the researchers hope to isolate the genes responsible for producing these proteins and insert them into tobacco for further insect tests. It is suggested that in the future similar gene insertions could be used in other food crops, such as grains, to allow those plants to produce their own insecticide.

^{M.B. Coelho et al., J. Agric. Food Chem., 58(5), 3050–3055 (2010).}

This story originally appeared in The Column. Click here to view that issue.