DNA barcoding augments conventional methods for identification of medicinal plant species traded at Tanzanian markets

Barcoding and traditional health practitioner perspectives are informative to monitor and conserve frogs and reptiles traded for traditional medicine in urban South Africa

Previous literature suggests that Indigenous cultural practices, specifically traditional medicine, are commonplace among urban communities contrary to the general conception that such practices are restricted to rural societies. We reviewed previous literature for records of herptiles (frog and reptile species) sold by traditional health practitioners in urban South Africa, then used visual confirmation surveys, DNA barcoding and folk taxonomy to identify the herptile species that were on sale. Additionally, we interviewed 11 IsiZulu and SePedi speaking traditional health practitioners to document details of the collection and pricing of herptile specimens along with the practitioners' views of current conservation measures for traditional medicine markets. The 34 herptile species recorded in previous literature on traditional medicine markets included endangered and non-native species. Spectrophotometry measurements of the DNA we extracted from the tissue of herptiles used in traditional medicine were an unreliable predictor of whether those extractions would be suitable for further experimental work. From our initial set of 111 tissue samples, 81 sequencing reactions were successful and 55 of those sequences had species-level matches to COI reference sequences on the NCBI GenBank and/or BOLD databases. Molecular identification revealed that traditional health practitioners correctly labelled 77% of the samples that we successfully identified with DNA barcoding in this study. Our mixed methodology approach is useful for conservation planning as it updates knowledge of animal use in Indigenous remedies and can accurately identify species of high conservation priority. Furthermore, this study highlights the possibility of collaborative conservation planning with traditional health practitioners.

An ethnopharmacological survey of medicinal plants traditionally used by the BaKalanga people of the Tutume subdistrict in Central Botswana to manage HIV/AIDS, HIV-associated conditions, and other health conditions

ETHNOPHARMACOLOGICAL RELEVANCE

While access to antiretroviral therapy (ART) continues to improve worldwide, HIV infection and AIDS persist as serious health challenges, particularly in sub-Saharan Africa. Complementary and Alternative Medicines (CAM), as part of indigenous and pluralistic medical systems, are important contributors to primary health care worldwide. However, this knowledge remains relatively undocumented in many parts of sub-Saharan Africa such as the Tutume subdistrict of Central Botswana, where CAM is widely used including potentially for HIV/AIDS and HIV-associated conditions.

AIM OF THE STUDY

To explore the extent to which CAM is used by the BaKalanga Peoples of the Tutume subdistrict, we performed an exploratory community-based project to record medicinal plant use from this relatively undocumented region, with a particular focus on species used for management of HIV/AIDS and HIV-associated conditions.

MATERIALS AND METHODS

Using the snowball sampling technique, we recruited 13 Traditional Health Practitioners (THPs) and conducted in-depth interviews to explore medicinal plant uses and treatment regimens. Plant specimens were collected and bio-authenticated.

RESULTS

We documented 83 plant species used as CAM to treat or manage a variety of conditions including HIV/AIDS, HIV-associated conditions, and other health conditions. Plants from the family Leguminosae were most frequently reported, comprising 21 species (25.3%), followed by 5 from both Euphorbiaceae and Combretaceae families (6.0%). Four plants (4.8%) were used specifically to manage HIV (Lannea edulis (Sond.) Engl. root, Aloe zebrina Baker root, Myrothamnus flabellifolia Welw. whole plant, and Harpagophytum procumbens var. subulobatum (Engl.) tuber), while an additional 7 (8.4%) were reported specifically for treating combinations of HIV-related symptoms. Notably, 25 (30.1%) have not been reported previously as CAM and/or lack reported bioactivity data.

CONCLUSIONS

To our knowledge, this is the first detailed ethnobotanical survey of CAM used by the BaKalanga Peoples of the Tutume subdistrict to manage HIV/AIDS and HIV-associated and other health conditions.

Senna singueana (Delile) lock: Ethnomedicinal uses and medicinal properties

Senna singueana (Delile) Lock is a potential medicinal plant commonly used to mitigate various infectious and non-infectious diseases including malaria, typhoid, gonorrhoea, bilharzia, cancer, epilepsy and ulcer. The phytochemical profile of S. singueana indicates the presence of different phytoconstituents corresponding to the pharmacological properties. The pharmacological potentials such as antibacterial, antifungal, antioxidant, antimalarial and antidiabetics are possessed by S. singueana. This review comprehensively discusses the potential of S. singueana for the mitigation of medical conditions. The information is collected from various online databases such as Google scholar, ScienceDirect, Springer, Web of Science and PubMed. Among other information, ethnomedicinal uses, phytochemistry, pharmacology and mechanisms of action are extensively presented. A review concluded by highlighting the challenges and potential future outlooks.

Successful identification of the species of the semipetrified amber medicinal resin benzoin using molecular diagnostic technology

Benzoin is an incomplete lithified resin secreted from the trunk of the Styrax Linn. that is known as "semipetrified amber" and has been widely used in medicine due to its blood circulation-promoting and pain-relieving properties. However, the lack of an effective species identification method due to the numerous sources of benzoin resin and the difficulty of DNA extraction has led to the uncertainty of species of benzoin in the trade process. Here, we report the successful extraction of DNA from benzoin resin containing bark-like residues and the evaluation of commercially available benzoin species using molecular diagnostic techniques. By performing a BLAST alignment of ITS2 primary sequences and homology prediction analysis of ITS2 secondary structures, we found that commercially available benzoin species were derived from Styrax tonkinensis (Pierre) Craib ex Hart. and Styrax japonicus Sieb. et Zucc. of the genus Styrax Linn. In addition, some of the benzoin samples were mixed with plant tissues from other genera, accounting for 29.6%. Therefore, this study provides a new method to solve the problem of species identification of semipetrified amber benzoin using information from bark residues.

ITS1 Barcode and Phytochemical Analysis by Gas Chromatography-Mass Spectrometry of Corynaea crassa Hook. f (Balanophoraceae) from Ecuador and Peru

The use of medicinal plants is the basis of traditional healthcare. Recently, the use of herbal medicine has been increasing among consumers due to availability, economy, and less side effect. For instance, the hemiparasite plant Corynaea crassa has medicinal properties and could be found in some regions of America, from Costa Rica to Bolivia. Phytochemical and genetic characterization of medicinal plants is needed for proper identification of metabolites responsible for medicinal properties and for genotyping, respectively. Moreover, characterization of medicinal plants through the use of DNA barcodes is an important tool for phylogenetic analysis and identification of species; furthermore, complemented with phytochemical analysis, both are useful for identification of plant species and quality control of medicinal products. The objective of this study was to analyze the species of C. crassa collected in Ecuador and Peru from the phylogenetic and phytochemical point of view. Polymerase chain reaction (PCR) was performed for amplification of the internal transcribed spacer 1 (ITS1) region after DNA extraction of samples of C. crassa. Blast analysis was performed in the GenBank database with the ITS1 sequences obtained from two accessions of C. crassa from Ecuador (GenBank accession numbers OM471920 and OM471919 for isolates CIBE-17 and CIBE-18, respectively) and three from Peru (GenBank accession numbers OM471921, OM471922, and OM471923 for isolates CIBE-13, CIBE-14, and CIBE-15, respectively). The accessions available in the GenBank were used for phylogenetic analysis. For the phytochemical analysis, hydroalcoholic extracts were obtained by maceration using 80% ethanol as solvent, followed by a derivatization process and analysis by gas chromatography-mass spectrometry. Based on the phylogenetic analysis of the C. crassa samples, the ITS1 sequence could be used to differentiate C. crassa of different locations. The samples of C. crassa from Ecuador and Peru are more similar between them than with other clades including Helosis spp. The phytochemical study revealed differences in the presence and relative abundance of some metabolites; mainly eugenol, 1,4-lactone arabinonic acid, dimethoxyrabelomycin and azelaic acid, which are reported for the first time for the species under study and the genus Corynaea. These results are the first findings on the combined analysis using genetic and phytochemical analysis for C. crassa, which could be used as a useful tool for quality control of the C. crassa species in medicinal products.

Effect of changes in business environments on traded medicinal plants products in Tanzania: An explorative study

In Tanzania, a complex rural to urban supply network for the medicinal plants' products trade has developed over time driven by changes in business environments at the macro level notably in the policy and regulatory frameworks and the micro level resulting from traders’ reactions and responses to those changes and pandemics. These changes in business environments and responses of traders have shaped the current trade practices. However, the response of traders to changes in business environments and the evolutionary paths over time are not well documented. Therefore, this paper aimed to synchronize changes in business environment over time and empirically determine how the trade has evolved concerning the responses of the medicinal plants' traders in Tanzania. The study applied economic evolution theory to describe the interactions of changes in business environments and responses of traders to demarcate the evolutionary stages. Primary data were collected from traders, regulators, and researchers through ten focus group discussions and sixteen in-depth interviews from five regions of Tanzania. The results indicated that the traders of medicinal plant products responded by improving product appearance and modernizing both practices and business premises. The study findings have identified four evolutionary stages of trade in medicinal plant products in Tanzania: The first stage was the colonial era (1882–1961), the second is the government supremacy era (1961–1984), the third is the emergence of the private sector era (1985–2004), and the fourth is the market and regulation integration era (started in 2005). Moreover, because of the partial implementation of the regulatory framework, the fifth stage of trade evolution is also expected. This stage is expected to be demarcated when the regulatory framework and market forces work together. Therefore, the study recommends that proper enforcement measures be put in place to ensure desired results whenever there are changes in business environments in traditional medicines practice. This is due to the expectation of the fifth stage whereby one of its characteristics is stiff competition among traders and which will require robust business models to survive in business.

Development and Application of a Cultivar-Specific Sequence-Characterized Amplified Region (SCAR) Marker for the Detection of Chrysanthemum morifolium Ramat. 'Daboju'

Chrysanthemummorifolium Ramat. 'Daboju' is a C. morifolium cultivar with important ornamental and medicinal values, and is often used in the treatment of colds, blurred vision, dizziness, and itchy skin. As the morphological characteristics of C. morifolium 'Daboju' are very similar to those of other C. morifolium cultivars, they are often confused in practice. However, the medicinal value and practical use of C. morifolium depends on using the correct rapid and accurate identification of C. morifolium 'Daboju' and its differentiation from other, morphologically similar C. × morifolium cultivars. Twenty-one polymorphic start codon-targeted (SCoT) primers were amplified in 21 distinct C. morifolium cultivars. One cultivar-specific DNA marker was developed with the aim of the rapid and accurate identification of C. morifolium 'Daboju' and its differentiation from other, similar C. morifolium cultivars. Twenty-one polymorphic start codon-targeted (SCoT) primers were amplified in 21 distinct C. morifolium cultivars. One cultivar-specific 385-bp amplicon (named SCoT36-385), amplified only in C. morifolium 'Daboju' (and in all samples of this cultivar), was identified, cloned, and sequenced. Subsequently, a sequence-characterized amplified region (SCAR) marker (named DBJF/DBJR), generating a 360-bp amplicon, was developed from SCoT36-385 and tested for amplification in all 21 C. morifolium cultivars, ten C. morifolium 'Daboju' populations, and different simulated adulterations of 'Daboju' with other cultivars. The primers amplified the specific 360-bp-long DNA fragment in all the tested C. morifolium 'Daboju' samples but failed in the absence of 'Daboju'. The detection limit of the SCAR primer pair (DBJF/DBJR) was 100 pg of DNA extracted from C. morifolium 'Daboju'. Hence, this SCAR marker has a very high detection sensitivity, and can be used for accurate and rapid identification of C. morifolium 'Daboju'. It can play an important role in ensuring the quality of medicinal preparations and protecting C. morifolium 'Daboju' germplasm resources in breeding programs and in identifying lines generated from this cultivar.

Challenges in Medicinal and Aromatic Plants DNA Barcoding-Lessons from the Lamiaceae

The potential value of DNA barcoding for the identification of medicinal plants and authentication of traded plant materials has been widely recognized; however, a number of challenges remain before DNA methods are fully accepted as an essential quality control method by industry and regulatory authorities. The successes and limitations of conventional DNA barcoding are considered in relation to important members of the Lamiaceae. The mint family (Lamiaceae) contains over one thousand species recorded as having a medicinal use, with many more exploited in food and cosmetics for their aromatic properties. The family is characterized by a diversity of secondary products, most notably the essential oils (EOs) produced in external glandular structures on the aerial parts of the plant that typify well-known plants of the basil (Ocimum), lavender (Lavandula), mint (Mentha), thyme (Thymus), sage (Salvia) and related genera. This complex, species-rich family includes widely cultivated commercial hybrids and endangered wild-harvested traditional medicines, and examples of potential toxic adulterants within the family are explored in detail. The opportunities provided by next generation sequencing technologies to whole plastome barcoding and nuclear genome sequencing are also discussed with relevant examples.

Chemometric-Guided Approaches for Profiling and Authenticating Botanical Materials

Botanical supplements with broad traditional and medicinal uses represent an area of growing importance for American health management; 25% of U.S. adults use dietary supplements daily and collectively spent over $9. 5 billion in 2019 in herbal and botanical supplements alone. To understand how natural products benefit human health and determine potential safety concerns, careful in vitro, in vivo, and clinical studies are required. However, botanicals are innately complex systems, with complicated compositions that defy many standard analytical approaches and fluctuate based upon a plethora of factors, including genetics, growth conditions, and harvesting/processing procedures. Robust studies rely upon accurate identification of the plant material, and botanicals' increasing economic and health importance demand reproducible sourcing, as well as assessment of contamination or adulteration. These quality control needs for botanical products remain a significant problem plaguing researchers in academia as well as the supplement industry, thus posing a risk to consumers and possibly rendering clinical data irreproducible and/or irrelevant. Chemometric approaches that analyze the small molecule composition of materials provide a reliable and high-throughput avenue for botanical authentication. This review emphasizes the need for consistent material and provides insight into the roles of various modern chemometric analyses in evaluating and authenticating botanicals, focusing on advanced methodologies, including targeted and untargeted metabolite analysis, as well as the role of multivariate statistical modeling and machine learning in phytochemical characterization. Furthermore, we will discuss how chemometric approaches can be integrated with orthogonal techniques to provide a more robust approach to authentication, and provide directions for future research.

Zanthoxylum Species: A Review of Traditional Uses, Phytochemistry and Pharmacology in Relation to Cancer, Infectious Diseases and Sickle Cell Anemia

The health benefits and toxicity of plant products are largely dependent on their secondary metabolite contents. These compounds are biosynthesized by plants as protection mechanisms against environmental factors and infectious agents. This review discusses the traditional uses, phytochemical constituents and health benefits of plant species in genus Zanthoxylum with a focus on cancer, microbial and parasitic infections, and sickle cell disease as reported in articles published from 1970 to 2021 in peer-reviewed journals and indexed in major scientific databases. Generally, Z. species are widely distributed in Asia, America and Africa, where they are used as food and for disease treatment. Several compounds belonging to alkaloids, flavonoids, terpenoids, and lignans, among others have been isolated from Z. species. This review discusses the biological activities reported for the plant species and their phytochemicals, including anticancer, antibacterial, antifungal, antiviral, anti-trypanosomal, antimalarial and anti-sickling properties. The safety profiles and suggestions for conservation of the Z. species were also discussed. Taken together, this review demonstrates that Z. species are rich in a wide range of bioactive phytochemicals with multiple health benefits, but more research is needed towards their practical application in the development of functional foods, nutraceuticals and lead compounds for new drugs.

DNA meta-barcoding using rbcL based mini-barcode revealed presence of unspecified plant species in Ayurvedic polyherbal formulations

INTRODUCTION

Ayurveda takes advantage of the beneficial properties of medicinal plants. High demands in combination with inadequate availability of botanicals and a lack of knowledge with respect to their precise identification lead to adulterations in herbal products. Identification becomes more difficult in complex herbal formulations. Four different polyherbal formulations have been analyzed for the present paper. The targeted plants have different pharmacological properties for various ailments.

OBJECTIVE

We aimed to examine the rbcL gene based plant DNA mini-barcode to identify target and non-target plants in polyherbal formulations by using high-throughput next generation sequencing.

METHODS

Degenerate primers of the selected mini-barcode region have been identified from the literature. A blend of 30 authentic medicinal plant species was used to examine the species resolution capacity of the mini-barcode. DNA was isolated from herbal formulations, an amplicon library was prepared, and sequencing was performed on an IonS5 system. Data were analyzed using various bioinformatics tools.

RESULTS

Analysis of control pooled samples revealed the optimum resolving power of the DNA mini-barcode. Data analysis of the commercial samples revealed that only one herbal formulation contained all plants and matched with listed contents. In two formulations, only 10 out of 21 and 11 out of 20 plants were detected, respectively. Additionally, several non-listed plants were also detected in these formulations. Two formulations contained >20% reads assigned to non-target plants. Overall, 21.98% of the reads were assigned to non-target plants.

CONCLUSION

The present study clearly demonstrated the successful application and potential of meta-barcoding in the quality control of complex herbal matrices. The results strongly suggest that this approach can be used in pharmacovigilance of processed herbal products.

Botanical authentication of globe artichoke-containing foods: Differentiation of Cynara scolymus by a novel HRM approach

Cynara scolymus L., known as globe artichoke, is a medicinal plant widely used in plant food supplements (PFS) and herbal infusions due to its beneficial health properties. The high demand for artichoke-containing products can lead to adulteration practices. In this work, a real-time polymerase chain reaction (PCR) system coupled to high-resolution melting (HRM) analysis was proposed to differentiate C. scolymus from other Cynara species. Hence, a Cynara-specific real-time PCR assay was successfully developed with high analytical performance, achieving a sensitivity of 0.4 pg of globe artichoke DNA. HRM analysis enabled the discrimination of C. scolymus, with a high level of confidence (>98%), corroborating sequencing data. Application results to artichoke-containing PFS and mixed herbal infusions allowed confirming the presence of C. scolymus in 38% of the samples, suggesting the substitution/mislabelling of globe artichoke in 2 samples and the need for further efforts to increase DNA amplifiability of PFS.

Identification of Vicia Species Native to South Korea Using Molecular and Morphological Characteristics

Recently, within the Fabaceae family, the Vicia genus has been recognized for its vital role in sustainable agriculture. Vicia species are economically important grain and forage crops. However, the presence of complex morphological characteristics makes identification and recognition of native species difficult. In this study, the possibility of using DNA barcoding regions (ITS2, matK, and rbcL) to distinguish among 19 Vicia taxa (59 accessions) found in South Korea was evaluated. The sequence alignment analysis revealed considerable nucleotide diversity (π) between the loci, in which ITS2 showed the highest mean interspecific distance, whereas there was no intraspecific variability among the barcode regions in 12 of the 19 taxa. Phylogenetic analysis of combined barcoding regions revealed well-resolved phylogeny with the highest species level discrimination. Combinations of barcode loci were also used in classification at the subgenera and section levels. The results revealed that the combined barcoding regions can be used effectively to differentiate the following species: Vicia angustifolia var. segetilis, Vicia bungei, Vicia villosa, Vicia cracca, Vicia dasycarpa, Vicia hirsuta, Vicia tetrasperma, Vicia amurensis, Vicia hirticalycina, and Vicia chosenensis. However, it is difficult to differentiate the species of Vicia unijuga, Vicia unijuga var. kaussanensis, Vicia linearifolia, Vicia unijuga f. angustifolia, Vicia nipponica, Vicia amoena, Vicia venosa var. cuspidata, Vicia pseudo-orobus, and Vicia japonica with the tested barcode regions. These species come under sect. Vicilla and are found to be closely related or species that have recently undergone speciation; thus, it has limitation to distinguish with recommended barcodes. Hence, to differentiate the unclassified species, 39 morphological characteristics were investigated, in which 16 useful characteristics were selected for efficient classification. Finally, the 16 selected morphological useful traits efficiently differentiated all the Vicia species. In conclusion, a combination of barcoding loci together with morphological characteristics of this study efficiently discriminated all the Korean Vicia species.

Differentiation of Cyanthillium cinereum, a smoking cessation herb, from its adulterant Emilia sonchifolia using macroscopic and microscopic examination, HPTLC profiles and DNA barcodes

Cyanthillium cinereum (L.) H.Rob. is one of the most popular herbal smoking cessation aids currently used in Thailand, and its adulteration with Emilia sonchifolia (L.) DC. is often found in the herbal market. Therefore, the quality of the raw material must be considered. This work aimed to integrate macro- and microscopic, chemical and genetic authentication strategies to differentiate C. cinereum raw material from its adulterant. Different morphological features between C. cinereum and E. sonchifolia were simply recognized at the leaf base. For microscopic characteristics, trichome and pappus features were different between the two plants. HPTLC profiles showed a distinct band that could be used to unambiguously differentiate C. cinereum from E. sonchifolia. Four triterpenoid compounds, β-amyrin, taraxasterol, lupeol, and betulin, were identified from the distinct HPTLC band of C. cinereum. The use of core DNA barcode regions; rbcL, matK, ITS and psbA-trnH provided species-level resolution to differentiate the two plants. Taken together, the integration of macroscopic and microscopic characterization, phytochemical analysis by HPTLC and DNA barcoding distinguished C. cinereum from E. sonchifolia. The signatures of C. cinereum obtained here can help manufacturers to increase the quality control of C. cinereum raw material in commercialized smoking cessation products.

A new method of metabarcoding Microsporidia and their hosts reveals high levels of microsporidian infections in mosquitoes (Culicidae)

DNA metabarcoding offers new perspectives, especially with regard to the high‐throughput identification and diagnostics of pathogens. Microsporidia are an example of widely distributed, opportunistic and pathogenic microorganisms in which molecular identification is important for both environmental research and clinical diagnostics. We have developed a method for parallel detection of both microsporidian infection and the host species. We designed new primer sets: one specific for the classical Microsporidia (targeting the hypervariable V5 region of small subunit [ssu] rDNA), and a second one targeting a shortened fragment of the COI gene (standard metazoan DNA‐barcode); both markers are well suited for next generation sequencing. Analysis of the ssu rDNA data set representing 607 microsporidian species (120 genera) indicated that the V5 region enables identification of >98% species in the data set (596/607). To test the method, we used microsporidians that infect mosquitoes in natural populations. Using mini‐COI data, all field‐collected mosquitoes were unambiguously assigned to seven species; among them almost 60% of specimens were positive for at least 11 different microsporidian species, including a new microsporidian ssu rDNA sequence (Microsporidium sp. PL01). Phylogenetic analysis showed that this species belongs to one of the two main clades in the Terresporidia. We found a high rate of microsporidian co‐infections (9.4%). The numbers of sequence reads for the operational taxonomic units suggest that the occurrence of Nosema spp. in co‐infections could benefit them; however, this observation should be retested using a more intensive host sampling. Our results show that DNA barcoding is a rapid and cost‐effective method for deciphering sample diversity in greater resolution, including the hidden biodiversity that may be overlooked using classical methodology.