DNA barcode based species-specific marker for Ocimum tenuiflorum and its applicability in quantification of adulteration in herbal formulations using qPCR

Comparative Morpho-micrometric Investigations in Six Indigenous Ocimum Species of India with DOE Based HPTLC Method for Multi-class Component Analysis

The Ocimum genus is one of India's prominent botanical classes of traditional medicinal culture comprising medicinally and agronomically important plants. Morphological resemblances, overlapping geographical distribution, and history of traditional nomenclature have necessitated a comprehensive qualitative report for effective quality control and removing the species ambiguity pertaining to this genus. This paper provides detailed morpho-micrometric characteristics used to differentiate between six indigenous Ocimum species of India. Among them, O. gratissimum was distinguished as the only shrub with a fleshy petiole. In green and purple forms, O. tenuiflorum leaves had serrate margins and showed no particular anatomical differences except for the anthocyanins containing epidermal cells of the latter. O. basilicum had glabrous leaves except for the veins, which were puberulous. O. filamentosum had tenuous anther filaments and was the least aromatic while O. africanum had a citrusy odour, which along with the number of xylary rows, size of mesophyll cells, and epidermal cell wall architecture, distinguished it from O. americanum. An HPTLC method was developed using experimental design and validated for quantification of multi-class compounds from terpenoic, phenolic acids, and flavonoids in Ocimum leaves. It was found linear (r ² > 0.99) with recoveries between 95 - 100% for all compounds. The eluted bands of marker compounds were subjected to HPTLC-MS analysis as a confirmative tool. This is the first anatomical and analytical report of O. filamentosum Forssk. The obtained results could be effectively used for species identification using vegetative characters alone with the anatomical-HPTLC data backing up the former as a rapid and economical tool.

Development of real-time PCR based molecular markers for two medicinal herb Artemisia species A. capillaris and A. iwayomogi

Artemisia capillaris and Artemisia iwayomogi are well-known herbal medicines which are used as hepatotherapeutic drugs. These two herbal species can be confused with each other, owing to their morphological similarity and similar Korean common names of "Injinho" and "Haninjin," respectively. Molecular markers to distinguish between the two plants were developed. Six primer sets were designed and verified, and their efficiencies were found to range from 90.28 to 98.29%. The developed primer sets had significant correlation coefficient values between the cycle threshold values and the logarithm of DNA concentration for their target species (R2 > 0.98), with slopes ranged from - 3.3637 to - 3.5793. The specificity of the quantitative polymerase chain reaction (qPCR) was confirmed with 14 other species. Additionally, 16 commercial medicinal herbs and 40 blind samples were tested to evaluate their reliability. Collectively, the findings indicate that developed qPCR-based target-specific primer sets have potential applicability toward protection of consumers' rights.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01166-0.

Advancements and future prospective of DNA barcodes in the herbal drug industry

Ethnopharmacological relevance: The past couple of decades have witnessed the global resurgence of medicinal plants in the field of herbal-based health care. Increased consumption of medicinal plants and their derivative products is the major cause of the adulteration issues in herbal industries. As a result, the quality of herbal products is affected by spurious and unauthorized raw materials. Recent development in molecular plant identification using DNA barcodes has become a robust methodology to identify and authenticate the adulterants in herbal samples. Hence, rapid and accurate identification of medicinal plants is the key to success for the herbal industry. Aim of the study: This paper provides a comprehensive review of the application of DNA barcoding and advanced technologies that have emerged over the past 10 years related to medicinal plant identification and authentication and the future prospects of this technology. Materials and methods: Information on DNA barcodes was compiled from scientific databases (Google Scholar, Web of Science, SciFinder and PubMed). Additional information was obtained from books, Ph.D. thesis and MSc. Dissertations. Results: Working out an appropriate DNA barcode for plants is challenging; the single locus-based DNA barcodes (rbcL, ITS, ITS2, matK, rpoB, rpoC, trnH-psbA) to multi-locus DNA barcodes have become the successful species-level identification among herbal plants. Additionally, multi-loci have become efficient in the authentication of herbal products. Emerging advances in DNA barcoding and related technologies such as next-generation sequencing, high-resolution melting curve analysis, meta barcodes and mini barcodes have paved the way for successful herbal plant/samples identification. Conclusion: DNA barcoding needs to be employed together with other techniques to check and rationally and effectively quality control the herbal drugs. It is suggested that DNA barcoding techniques combined with metabolomics, transcriptomics, and proteomics could authenticate the herbal products. The invention of simple, cost-effective and improved DNA barcoding techniques to identify herbal drugs and their associated products of medicinal value in a fool-proof manner will be the future thrust of Pharmacopoeial monograph development for herbal drugs.

A Review on Application of DNA Barcoding Technology for Rapid Molecular Diagnostics of Adulterants in Herbal Medicine

The rapid molecular diagnostics of adulterants in herbal medicine using DNA barcoding forms the core of this meticulously detailed review, based on two decades of data. With 80% of the world's population using some form of herbal medicine, authentication, quality control, and detection of adulterants warrant DNA barcoding. A combined group of keywords were used for literature review using the PubMed, the ISI Web of Knowledge, Web of Science (WoS), and Google Scholar databases. All the papers (N = 210) returned by the search engines were downloaded and systematically analyzed. Detailed analysis of conventional DNA barcodes were based on retrieved sequences for internal transcribed spacer (ITS) (412,189), rbcL (251,598), matK (210,835), and trnH-psbA (141,846). The utility of databases such as The Barcode of Life Data System (BOLD), NCBI, GenBank, and Medicinal Materials DNA Barcode Database (MMDBD) has been critically examined for the identification of unknown species from known databases. The current review gives an overview of the ratio of adulterated to authentic drugs for some countries along with the state of the art technology currently being used in the identification of adulterated medicines. In this review, efforts were made to systematically analyze and arrange the research and reviews on the basis of technical progress. The review concludes with the future of DNA-based herbal medicine adulteration detection, forecasting the reliance on the metabarcoding technology. DNA barcoding technology for differentiating adulterated herbal medicine.

Characteristic Malonyl Ginsenosides from the Leaves of Panax notoginseng as Potential Quality Markers for Adulteration Detection

Due to the high price and limited supply of Panax notoginseng, a large number of samples adulterated with the leaves appear in the market. A group of new malonyl ginsenosides were exclusively detected in the P. notoginseng leaves (PNL). Targeted isolation of the malonyl ginsenosides was guided by UPLC-QDa MS. HRMS, 1D/2D NMR, and chemical methods were used for structural identification. A selected ion monitoring method was developed based on UPLC-QDa MS to detect the adulterations. In addition, the anti-inflammatory activities and the collision-induced dissociation features of the isolated saponins were studied. As a result, eight new 3-OH malonylated dammarane-type triterpene oligoglycosides (notoginsenosides L3-L10) were obtained from PNL. Adulteration with PNL can be easily detected with limit of detection as low as 0.06%. To sum up, the isolated ginsenosides can be used as quality markers for fraud detection, which will promote the quality control of the notoginseng products.