Wood from Hardwood Angiosperms and Coniferous Gymnosperms Shows Distinctive Lignin Peaks in Direct Analysis in Real Time (DART) Mass Spectra.

A data set was constructed consisting of 3021 mass spectra randomly selected from all available families in the ForeST© (Forensic Spectra of Trees) database of mass spectra for wood analyzed by Direct Analysis in Real Time ionization coupled with time-of-flight mass spectrometry (DART-TOFMS). Clear and reproducible differences were observed between the lignin peaks for hardwood angiosperms and coniferous gymnosperms, with DART-TOFMS spectra of angiosperms showing significantly higher relative abundances for peaks associated with syringyl subunits. Application of the method to processed wood samples demonstrated that these differences can be used to provide support for enforcing trade laws by accurately identifying the source of finished wood products from hardwood angiosperms and coniferous gymnosperms.

Identification of rhinoceros keratin using direct analysis in real time time-of-flight mass spectrometry and multivariate statistical analysis.

RATIONALE: Trade in rhinoceros horn is regulated or banned internationally in recognition of its impact on wild populations worldwide. Enforcement of the laws and regulations depends on successfully identifying when violations occur, which is complicated by the presence of alternative/imitation rhinoceros horn keratin (e.g., bovid horn keratin). In this study, we assess the potential for Direct Analysis in Real Time (DART) ionization paired with Time-Of-Flight Mass Spectrometry (DART-TOFMS) to classify different keratin types from four taxonomic groups: rhinoceros, bovid, domestic horse, and pangolin. METHODS: The spectra of 156 keratin samples from all five rhinoceros species (horn keratin), eight genera of bovids (horn keratin), domestic horses (hoof keratin), and all extant species of pangolins (scale keratin) were collected. Fisher ratio analysis identified the most important ions that characterized each class and these ions were used for the training model, which consisted of 143 spectra. Kernel Discriminant Analysis (KDA) was used to classify the different groups. RESULTS: The spectra collected for each taxonomic group are distinctive. The chemotypes demonstrate that the spectra of rhinoceros, bovids, and domestic horse are similar to each other, whereas the chemotypes of pangolins show a different chemical profile. The model built by KDA resolved each taxonomic group: 95% of samples were correctly assigned using leave-one-out cross validation. The 13 blind samples not used in model development were all correctly classified to taxonomic source. CONCLUSIONS: 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.

Metabolic chemotypes of CITES protected Dalbergia timbers from Africa, Madagascar, and Asia.

RATIONALE: The genus Dalbergia includes approximately 250 species worldwide. Of these, 58 species are of economic importance and listed under CITES. Identification of illegal transnational timber trade is a challenge because logs or boards lack the typical descriptors used for species identification such as leaves and flowers; therefore, frequently the lowest taxonomic determination of these tree byproducts is genus. In this study, we explore the use of Direct Analysis in Real Time (DART) Time-Of-Flight Mass Spectrometry (TOFMS) in making species determinations of protected Dalbergia trees from Africa, Madagascar, and Asia. METHODS: Metabolic profiles were collected using DART TOFMS from the heartwood of seven species and the sapwood of 17 species of Dalbergia. Also included in this study are 85 Dalbergia heartwood samples from Madagascar that were only identified to genus. In all, 21 species comprising 235 specimens were analyzed, the metabolic chemotypes were interpreted, and the spectra were analyzed using chemometric tools. RESULTS: Dalbergia cochinchinensis and Dalbergia spp. from Madagascar (both CITES Appendix II) could be differentiated from each other and from the non-protected Dalbergia latifolia and Dalbergia melanoxylon. CONCLUSIONS: DART TOFMS is a valuable high-throughput tool useful for making phytochemical classifications of Dalbergia spp. The data produced allows the protected Dalbergias from Madagascar to be distinguished and can differentiate closely related rosewood trees.

Forensic analysis of black coral (Order Antipatharia).

Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported.