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bioRxiv · 10.1101/2023.01.11.523696

DNA metabarcoding using new rbcL and ITS2 metabarcodes collectively enhance detection efficiency of medicinal plants in single and polyherbal formulations

Travadi, T.·Shah, A. P.·Pandit, R.·Sharma, S.·Joshi, C.·Joshi, M.
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Abstract

With the widespread adoption of barcoding and next-generation sequencing, metabarcoding is emerging as a potential tool for detecting labelled and unlabelled plant species in herbal products. In this study, newly designed rbcL and ITS2 metabarcode primers were validated for metabarcoding using in-house mock controls of medicinal plant gDNA pools and biomass pools. The applicability of the multi-barcode sequencing approach was evaluated on 17 single drugs and 15 polyherbal formulations procured from the Indian market. The rbcL metabarcode demonstrated detection efficiencies of 86.7% and 71.7% in gDNA plant pools and biomass mock controls, respectively, while the ITS2 metabarcode demonstrated 82.2% and 69.4%. In the gDNA plant pool and biomass pool mock controls, the cumulative detection efficiency increased by 100% and 90%, respectively. A total of 79% cumulative detection efficiency of both metabarcodes was observed in single drugs, while 76.3% was observed in polyherbal formulations. An average fidelity of 83.6% was observed for targeted plant species present within mock controls as well as in herbal formulations. Our results demonstrated the applicability of multilocus strategies in metabarcoding as a potential tool for detecting labelled and unlabelled plant species in herbal formulations.

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Travadi, T., Shah, A. P., Pandit, R., Sharma, S., Joshi, C., Joshi, M.. 2023-01-12. DNA metabarcoding using new rbcL and ITS2 metabarcodes collectively enhance detection efficiency of medicinal plants in single and polyherbal formulations. https://doi.org/10.1101/2023.01.11.523696

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