DART-TOFMS appears to be a reliable approach for taxonomic identification of keratin. This analysis can be carried out with a small sliver of keratin, with minimal sample preparation, inexpensively and quickly, making it a potential valuable tool for identification of rhinoceros horn and other keratin types.

Attention to illegal logging practices and demanding policies in transnational timber trade have driven the need for species-level identification of timber. Historically wood has been identified to genus level using microscopy and anatomical characteristics, however, new chemometric and imaging methods have been developed to increase the speed and precision of timber identification. This study approaches species identification using a combination of complementary methods: Direct Analysis in Real Time–Time-of-Flight Mass Spectrometry (DART-TOFMS), wood anatomy, and fluorescence spectroscopy. Seven commercially and environmentally significant species in Pterocarpus, including P. erinaceus (CITES Appendix II), P. santalinus (CITES Appendix II), P. tinctorius (CITES Appendix II), P. indicus, P. macrocarpus, P. dalbergioides, and P. soyauxii were studied. It was found that DART-TOFMS paired with discriminant analysis of principal components (PCA) could classify species with an accuracy of 95–100%, while anatomy in combination with PCA applied to fluorescence spectra could be used to classify CITES Appendix II species. In the absence of access to DART-TOFMS, a combination of wood anatomy and fluorescence spectrometry can permit more accurate identification than anatomy alone.

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Background To enforce timber import laws and perform timber species identification, the identity of the botanical species must be well-defined. Since the Sapotaceae family is known as a taxonomically challenging family, we focus in this study on the four most valuable Sapotaceae timber species from tropical Africa: Autranella congolensis (De Wild.) A.Chev., Baillonella toxisperma Pierre, Tieghemella africana Pierre and Tieghemella heckelii (A.Chev.) Pierre ex Dubard. The wood anatomical characteristic fiber lumen fraction and Direct Analysis in Real Time—Time of Flight Mass Spectrometry (DART-TOFMS) were used to differentiate the four species and to make inferences on species delineation and taxonomic identity. Results We observed differences in the fiber lumen fraction measurements and discerned two groups: (1) A. congolensis and B. toxisperma, and (2) T. africana and T. heckelii. In addition, all Mann–Whitney U comparisons and differences in distributions (Kolmogorov–Smirnov) for the fiber lumen fraction measurements were significant between all species. When permutating the data between species within those two groups, significant differences were still found between the species within those groups. This could indicate that the fiber lumen fraction is not diagnostic to discern the species. DART-TOFMS analysis showed that A. congolensis and B. toxisperma have distinct chemotypes, while T. heckelii and T. africana have remarkably similar chemotypes. Conclusions Based on our observations of similar chemotype and weakly differentiated fiber lumen ratio, we support an alternative taxonomic hypothesis that considers Tieghemella monotypic, because of the strong resemblance between T. heckelii and T. africana. Larger sample sizes and further research is required to develop methodology for the identification of these species. A taxonomic study utilizing molecular genetics would be beneficial to assess the status of the genus and the species limits. This could have implications towards their potential inclusion on CITES appendices if there is ever need for them to be listed. If Tieghemella africana and T. heckelii remain two distinct species, they should both be listed. Screening agents should be aware that the morphological and chemical differences between T. africana and T. heckelii are minimal.