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As laws tighten to limit commercial ivory trading and protect threatened species like whales and elephants, increased sales of fake ivory products have become widespread. This study describes a method, handheld X-ray fluorescence (XRF) as a noninvasive technique for elemental analysis, to differentiate quickly between ivory (Asian and African elephant, mammoth) from non-ivory (bones, teeth, antler, horn, wood, synthetic resin, rock) materials. An equation consisting of 20 elements and light elements from a stepwise discriminant analysis was used to classify samples, followed by Bayesian binary regression to determine the probability of a sample being ‘ivory’, with complementary log log analysis to identify the best fit model for this purpose. This Bayesian hybrid classification model was 93% accurate with 92% precision in discriminating ivory from non-ivory materials. The method was then validated by scanning an additional ivory and non-ivory samples, correctly identifying bone as not ivory with >95% accuracy, except elephant bone, which was 72%. It was less accurate for wood and rock (25–85%); however, a preliminary screening to determine if samples are not Ca-dominant could eliminate inorganic materials. In conclusion, elemental analyses by XRF can be used to identify several forms of fake ivory samples, which could have forensic application.

Identifying human remains is a primary task in forensic science. In this study, we propose a possible new technique, handheld X-ray fluorescence (HHXRF), for determining whether a suspected tooth is an authentic human tooth. A total of 444 teeth obtained from 111 human skulls (male = 62, female = 49) aged between 30–67 years (51.81 ± 8.37 years) were used as subjects. The teeth were scanned by HHXRF to acquire their elemental profile. Differences in elemental composition were analyzed for different tooth positions (numbers 1–32), between crown and root, and between sexes (male and female); also, the proportion of elements in relation to different human ages was examined. Teeth from 20 different animal species, serving as non-human teeth samples, were used to distinguish between human and non-human teeth through a stepwise discriminant analysis. Our results revealed that different tooth positions, different regions (crown and root) of a tooth, and different sexes demonstrated disparities in the proportion of several elements. The accuracy rate of predicting sex based on the elemental profile of human teeth was 65.5%. Likewise, a dissimilar distribution of elements between human and non-human teeth was observed, leading to a high degree of correctness of 83.2% for distinguishing them. In conclusion, elemental analysis by HHXRF could serve as a promising candidate tool for identifying human teeth in forensic science, but is ineffective for sex determination.

Pangasianodon gigas (giant catfish) is well-recognized as a critically endangered species due to overhunting and habitat degradation. Giant catfish aquaculture has expanded to meet the ever-increasing demands with augmented prices. Contamination or substitution of P. gigas products with other related species e.g. Pangasianodon hypophthalmus and Pangasius larnaudii because of their similar morphology but lower cost requires investigation. A method was established to differentiate species by mini-barcodes or microsatellites conjugated with high resolution melting analysis (minibar-HRM or microsatellite-HRM) using mitochondrial genes cytochrome c oxidase subunit I (COI), cytochrome b (Cytb), the nuclear recombination activator gene 1 (Rag1) and two microsatellite loci (Pg-9 and Pg-13). Results revealed that primer sets for the mitochondrial genes PanCytb1 and PanCytb2 showed a significant difference in melting shapes and melting temperature (Tm) between the three species. For nuclear genes, a single locus was not sufficient to discriminate between the three species, and at least two loci such as PanRag1 + Pg9 or PanRag1 + Pg13 were required. The sufficient amount of DNA for species discrimination using minibar-HRM with PanCytb1 and PanCytb2 was suggested as at least 5 pg. This method can also be used for adulteration determination of the P. gigas substitution with P. hypophthalmus and P. larnaudii at greater than 5% adulteration. Findings demonstrated that mini-barcode or microsatellite-HRM offered optimal performance for species discrimination of P. gigas, P. hypophthalmus and P. larnaudii. This approach can be adopted for hybrid detection using PanRag1 + Pg9 or PanRag1 + Pg13-HRM and PanCytb1 or PanCytb2 for matrilineal detection to benefit aquaculture research and quality control on a commercial scale.

Recently, the incidence of canine infection by the tick-borne parasites Babesia spp., Hepatozoon canis, Ehrlichia canis and Anaplasma platys has been increasing globally. We have developed a multiplex high-resolution melting analysis (mHRM) technique to reduce the time demands and costs associated with detecting haemoparasites in canine blood, while increasing the degree of reliability of this method of analysis. We have designed primers that are specific for protozoans (B. vogeli and H. canis) and Rickettsia-like bacteria (E. canis and A. platys) based on the 18S or 16S rDNA sequences, respectively. Two primer pairs (Protz18S-C and Bact16S-A) were found to be suitable for detecting these agents since their melting temperatures (Tm) exhibited discernible differences among the four haemoparasites, A. platys, B. vogeli, E. canis and H. canis (83.10 °C, 82.41 °C, 80.37 °C and 78.56 °C, respectively). The sequences acquired from these PCR products were >94 % identical to those of A. platys, B. vogeli, E. canis and H. canis in GenBank. The limit of detection (LOD) for B. vogeli, E. canis and A. platys was 103 copies/μl, while the LOD for H. canis was 104 copies/μl. Of the 68 dogs tested, 28 (41 %) were infected with these agents. The most commonly occurring infection involved E. canis, followed by B. vogeli, A. platys and H. canis, with infection percentages of 26 %, 13 %, 7 % and 6 %, respectively. These results demonstrate that mHRM can serve as a rapid, economical and reliable tool for the detection of parasitic diseases in canine blood for diagnosis and epidemiology.

Objective To explore the suppression effect of six Thai plants on matrix-degrading enzymes such as collagenase and matrix metalloproteinases (MMPs). Methods Six Thai plant extracts, Phyllanthus niruri (P. niruri), Vernonia cinerea, Pluchea indica, Rhinocanthus nasutus (R. nasutus), Zingiber cassumunar (Z. cassumunar) and Cissus quadrangularis (C. quadrangularis) were tested for total phenolic content, antioxidant, DNA protection, anti-collagenase properties and inhibitory effects on IL-1β-acitvated MMP-3 expression. Additionally, the ethanolic extracts of P. niruri and Z. cassumunar were assessed for MMP-2 and −9 production using gelatin zymography. Results An evaluation of antioxidant activity and total phenolic content revealed that the ethanolic extract of P. niruri had the highest activity (72.17 and 93.05 mg gallic/g extract, respectively). The ethanolic extracts of P. niruri, Vernonia cinerea, R. nasutus and C. quadrangularis performed a strong activity of DNA protection against hydroxyl radicals. The extracts of C. quadrangularis, R. nasutus and P. niruri (IC50 = 0.3, 0.82 and 0.91 mg/mL, respectively) possessed good activity for the inhibition of bacterial collagenase activity. Using the promoter activity assay, the ethanolic extract of P. niruri and Z. cassumunar (IC50 = 26.94 and 27.82 µg/mL, respectively) decreased IL-1β-stimulated MMP-3 expression in human chondrosarcoma cells (SW1353) cells. Besides, both the ethanolic extracts of P. niruri and Z. cassumunar could alleviate the production of MMP-2 and −9 in IL-1β-activated SW1353. Conclusions Taken together, the ethanolic extract of P. niruri had several beneficial effects.