Forensic botany and forensic chemistry working together: application of plant DNA barcoding as a complement to forensic chemistry-a case study in Brazil

Investigating DNA barcodes of plants growing in some areas of Iran with high crime rate: Quercus brantii, Curpressus arizonica, Crataegus pentagyna, Ziziphus Spina-chtista, and Buxus hyrcana

According to criminal botany, the offender unknowingly carries plant samples from the crime scene. Therefore, studying the genetic data of plants native to the crime scene can solve many ambiguities in the criminal files. In this regard, the aim of this study was to investigate the genome of 5 endemic plants in some areas of Iran with high crime rate. Quercus brantii, Curpressus arizonica, Crataegus pentagyna, Ziziphus Spina-chtista, and Buxus hyrcana were assessed using 1 genetic fragment on plastid regions (trnH-psbA) as well as 1 gene on nuclear chromosome called ITS. The alignment of DNA sequences of trnH-psbA and ITS genes was done using BioEdit, Clustal X, and Muscle v4.0 software programs. The phylogenetic analysis was performed on aligned data using Maximum Parsimony (MP) and the Bayesian methods. The Splits Tree v.4.14.4 software program was used for phylogenetic network analysis. Finally, the data combinability test was conducted using the Incongruence Length Difference (ILD) test by PAUP* software program. All data from nrDNA ITS and trnH-psbA sequences were consistent with Information Compatibility Test (ICT) results. Moreover, the nrDNA ITS indicated more resolved relationship than trnH-psbA. The results from MP and Bayesian analyses did not differ significantly between singular and combined forms, except for a slight variance in confidence interval of branches. As the phylogenetic trees provide more thorough and deeper conception of species relations, it is hoped that they would be useful to illuminate some forensic gaps in regions with high crime rates enriched by these plants, not only in Iran, but also in all areas over the world with this vegetation.

DNA Barcoding Medicinal Plant Species from Indonesia

Over the past decade, plant DNA barcoding has emerged as a scientific breakthrough and is often used to help with species identification or as a taxonomical tool. DNA barcoding is very important in medicinal plant use, not only for identification purposes but also for the authentication of medicinal products. Here, a total of 61 Indonesian medicinal plant species from 30 families and a pair of ITS2, matK, rbcL, and trnL primers were used for a DNA barcoding study consisting of molecular and sequence analyses. This study aimed to analyze how the four identified DNA barcoding regions (ITS2, matK, rbcL, and trnL) aid identification and conservation and to investigate their effectiveness for DNA barcoding for the studied species. This study resulted in 212 DNA barcoding sequences and identified new ones for the studied medicinal plant species. Though there is no ideal or perfect region for DNA barcoding of the target species, we recommend matK as the main region for Indonesian medicinal plant identification, with ITS2 and rbcL as alternative or complementary regions. These findings will be useful for forensic studies that support the conservation of medicinal plants and their national and global use.

Forensic botany: time to embrace natural history collections, large scale environmental data and environmental DNA

Forensic botany is a diverse discipline that spans many aspects of plant sciences, particularly taxonomy, field botany, anatomy, and ecology. Internationally, there is a significant opportunity to expand the application of forensic botany in criminal investigations, especially war crimes, genocide, homicide, sexual violence, serious physical assault, illegal trade in endangered species and wildlife crime. In civil proceedings, forensic botany may, for example, be called upon in trade disputes such as accidental contamination of commodities. Despite the potential, there are barriers to the wider application of forensic botany in criminal cases; there is a widespread need to improve the efficiency of botanical trace evidence identification. This could partly be addressed by embracing innovations in image recognition and by accessing the huge quantity of specimens and images housed in natural history collections worldwide. Additionally, the recent advances in DNA sequencing technologies and the expansion of environmental DNA (eDNA) and forensic ecogenomics, offers opportunities to more rapidly provide species-level identifications. The impact of taphonomic processes upon vegetation, and vice versa, remains poorly understood; improved understanding of these interactions and their ecological impacts may be invaluable in improving clandestine burial search protocols.

Microbiomes in forensic botany: a review

Fragments of botanical material can often be found at crime scenes (on live and dead bodies, or on incriminating objects) and can provide circumstantial evidence on various aspects of forensic investigations such as determining crime scene locations, times of death or possession of illegal species. Morphological and genetic analysis are the most commonly applied methods to analyze plant fragment evidence but are limited by their low capacity to differentiate between potential source locations, especially at local scales. Here, we review the current applications and limitations of current plant fragment analysis for forensic investigations and introduce the potential of microbiome analysis to complement the existing forensic plant fragment analysis toolkit. The potential for plant fragment provenance identification at geographic scales meaningful to forensic investigations warrants further investigation of the phyllosphere microbiome in this context. To that end we identify three key areas of future research: 1) Retrieval of microbial DNA of sufficient quality and quantity from botanical material; 2) Variability of the phyllosphere microbiome at different taxonomic and spatial scales, with explicit reference to assignment capacity; 3) Impacts on assignment capacity of time, seasonality and movement of fragments between locations. The development of robust microbiome analysis tools for forensic purposes in botanical material could increase the evidentiary value of the botanical evidence commonly encountered in casework, aiding in the identification of crime scene locations.

DNA from wood - A simple approach facing a challenging matrix - A preliminary study

Plant DNA barcoding has proven to be a handy tool for identifying botanical species. However, extracting DNA from woody materials is often a challenging task. Forensic applications, therefore, must be able to overcome the technical difficulties of this nature. A simple and successful adaptation, through a widely used method in forensic laboratories, using chemistry based on magnetic DNA isolation technology and a robotic platform, is presented here. The model case was the application of this adapted DNA extraction method for the identification of Aspidosperma spp., a genus comprising several species in all biomes of Brazil, including Cerrado and Rain Forest. Such technology adaptation can aid in the identification of seized material and help in investigations involving illegal logging and deforestation, ultimately contributing to environmental protection.

DNA Authentication of St John's Wort (Hypericum perforatum L.) Commercial Products Targeting the ITS Region

There is considerable potential for the use of DNA barcoding methods to authenticate raw medicinal plant materials, but their application to testing commercial products has been controversial. A simple PCR test targeting species-specific sequences within the nuclear ribosomal internal transcribed spacer (ITS) region was adapted to screen commercial products for the presence of Hypericum perforatum L. material. DNA differing widely in amount and extent of fragmentation was detected in a number of product types. Two assays were designed to further analyse this DNA using a curated database of selected Hypericum ITS sequences: A qPCR assay based on a species-specific primer pair spanning the ITS1 and ITS2 regions, using synthetic DNA reference standards for DNA quantitation and a Next Generation Sequencing (NGS) assay separately targeting the ITS1 and ITS2 regions. The ability of the assays to detect H. perforatum DNA sequences in processed medicines was investigated. Out of twenty different matrices tested, both assays detected H. perforatum DNA in five samples with more than 10³ ITS copies µL⁻¹ DNA extract, whilst the qPCR assay was also able to detect lower levels of DNA in two further samples. The NGS assay confirmed that H. perforatum was the major species in all five positive samples, though trace contaminants were also detected.