Comparative Analysis of Volatile Constituents of Pachira aquatica Aubl. and Pachira glabra Pasq., their Anti-Mycobacterial and Anti-Helicobacter pylori Activities and their Metabolic Discrimination using Chemometrics

The leaves and stems of the two Pachira species cultivated in Egypt, namely Pachira aquatica, and Pachira glabra were qualitatively and quantitatively examined for their volatile constituents employing GC/FID and GC/MS. Sixty compounds have been identified from P. aquatica leaves and stem representing 87.26 and 90.14%, respectively of their total oil content. However, fifty seven compounds were determined from P. glabra leaves and stems representing 89.67 and 94.69%, respectively. Trans-phytol represented the major component of P. glabra leaf oil with a content of 28.72% of the oil, however β-cadinene (15.46%), was the predominating compound in P. glabra stem oil. Palmitic acid methyl ester (21.08%) and 9,12-octadecadienoic acid ethyl ester (26.20%) were the prevailing constituents in Pachira aquatica leaves and stems oil, respectively. Hierarchical cluster analysis (HCA) and principle component analysis (PCA) as unsupervised chemometric technique were successfully employed to differentiate the two morphologically close related species based upon their GC chromatograms. Only P. aquatica leaf oil showed effectiveness against both Mycobacterium tuberculosis and Helicobacter pylori infection showing MIC values of 50 and 20 μg/mL against them, respectively emphasizing its potent inhibitory activity against both hazardous infections. Thus, volatile constituents from the P. aquatica leaves offer a natural, cheap and relatively safe candidate for pharmaceutical industries to combat these life-threatening bacterial infections.