Herbal medicines are growing in popularity in the Western world and are becoming more stringently regulated under new EU legislation. Within the arena of herbal medicines, St. John’s Wort (SJW), Hypericum perforatum, is a top ten best seller with clinical evidence to support its use as an anti-depressant. A fundamental requirement of the new legislation is to prove the identity of the plant material in question. This is currently achieved via morphological and chemical methods, neither of which are ideal. A wide range of DNA based methods have been applied to this arena, standardisation is required to realise the potential of DNA based techniques. The DNA barcoding initiative aims to produce sequence data for all plant species, capable of species identification. The proposal is to use these data to design fast and effective DNA based methods of identification. For assay design, the putative barcode region nrITS was selected as a platform. Three assays were designed; • A PCR assay designed to hyper variable sequences within a barcode region. This assay is capable of distinguishing SJW from other closely related species. • A quantitative qPCR assay designed to measure total DNA and specific SJW DNA within a mixed sample. • A multiplex PCR incorporating fluorescently labelled primers, allowing amplicon detection by capillary electrophoresis. This assay identifies four separate Hypericum species, including SJW, with a mixed sample in one reaction. The suitability of the nrITS and three other barcode regions is assessed based on sequence data generated for 32 vouchered samples of different Hypericum species, and a Lithuanian sample set of 22 and 16 H. perforatum and H. maculatum samples respectively. The matK is currently unusable, the rbcL highly conserved, trnH-psbA problematically variable and the nrITS proved to be ideal for assay design.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Herbal medicines (HMs) have been used to supplement, maintain, and treat health conditions, and have inspired the development of many Western pharmaceuticals. Migrant South Asian (SA) communities in the UK have brought with them their own traditional forms of medicine, yet little is known about their current use of HMs in the UK. Consuming HMs alongside conventional Western medicines could affect pharmacological treatment and lead to herb-drug interactions; hence, healthcare professionals (HCPs) should be aware of their patients’ use of HMs. The import of HMs to the UK raises concerns over the quality, safety and regulation of HMs. Deoxyribonucleic acid (DNA) barcoding can be used to discriminate between different species, and identify contaminants and adulterants, thus can be used for the authentication of HMs. The South Asian Traditional Medicines (SATMED) questionnaire explored the knowledge and use of HMs by diasporic SA communities in the UK. It uncovered a vast range of HMs which were used by participants, where ingredients were sourced from, the concurrent use of herbal and Western medicines, and how minor ailments were treated. An online survey designed to investigate UK based practitioners’ views of HMs revealed that HCPs claimed to lack sufficient knowledge of HMs. HCPs said they needed more training on HMs to help them make better informed decisions. Tulsi (Ocimum tenuiflorum L.) was identified as a culturally and commercially valuable plant, which was used for molecular analysis. A variety of tulsi samples were collected for authentication: community samples from SA families in the UK, commercial samples, and referenced specimens. Both ITS and trnH-psbA regions were successfully used to distinguish between several Ocimum species, and identify a potential species substitution. This research represents the first time that DNA based methods have been used to authenticate medicinal plants species used by migrant SA communities living in the UK. The results of this multi-disciplinary study provide a unique contribution to the evolving discipline of ethnopharmacology.