Differentiation of Toxic and Non-Toxic Leaves of Jatropha curcas L. Genotypes by Leaf Spray Mass Spectrometry

Jatropha curcas L. is an oil crop that has been studied as a potential source of biodiesel. A high protein pie is produced as a byproduct of the biodiesel production, which could be used as animal feed. However, the pie has toxic compounds, as phorbol esters and other toxins, which prevents the use as animal feed. For this reason, Embrapa (Brazilian Agricultural Research Corporation) has been working in genetic breeding to develop non-toxic J. curcas genotypes. To evaluate this process, a simple and fast analytical technique was employed to obtain responses in a short time. Leaf spray (LS) is a recent ambient ionization mass spectrometry technique in which the sample itself serves as support and ion source. Here, toxic and non-toxic J. curcas leaves were differentiated by LS using a linear ion trap mass spectrometer and partial least squares discriminant analysis (PLS-DA) model chemometrics. It was possible to differentiate toxic and non-toxic leaves and to identify the m/z values that contribute to discrimination between the groups.