Fig. 4
![Fig. 4](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40494-020-00449-1/MediaObjects/40494_2020_449_Fig4_HTML.png)
a Py-GC/MS chromatogram obtained upon derivatization with TMAH of sample S5, i.e. a small chip of untinted resin from the gourd’s interior, compared with b a chromatogram acquired in the same conditions from a reference sample of Elaeagia pastoensis boiled resin. Compounds identified in both chromatograms include glycerol derivatives along with various fatty acids, several molecules containing a single aromatic group, two cinnamic acid derivatives, a series of unidentified but characteristic compounds, the dimethyl and trimethyl ethers of apigenin, as well as the tetramethyl ether of luteolin, and numerous pentacyclic triterpenoids