Helen Sheridan

By Jinfan Wang, Astrid Sasse and Helen Sheridan

Traditional Chinese medicine (TCM) is one of the most established systems of medicine in the world. The therapeutic formulae used in TCM are frequently derived from aqueous decoctions of single plants or complex multicomponent formulae. There are aspects of plant cultivation and preparation of decoction pieces that are unique to TCM. These include Daodi cultivation, which is associated with high quality medicinal plant material that is grown in a defined geographical area, and Paozhi processing where the decoction pieces can be treated with excipients and are processed, which may fundamentally change the nature of the chemical metabolites. Therefore, a single plant part, processed in a variety of different ways, can each create a unique medicine. The quality of TCM materials, their safety and therapeutic efficacy are of critical importance. The application of metabolomic and chemometric techniques to these complex and multicomponent medicines is of interest to understand the interrelationships between composition, synergy and therapeutic activity. In this chapter, we present a short history of TCM, detail the role of Daodi and Paozhi in the generation of therapeutic formulae and look at the international practices and methodologies currently in use to ensure their sustainable production, quality, safety and efficacy.

Part of the book: Plant Extracts

By Ciara Smyth and Helen Sheridan

This study explores ethnobiological and bioprospecting research through the lens of Carissa spinarum L., using it as a case study to examine wider trends in such research. Hunn’s Phasing in Ethnobiology is used as a framework, analysing the extensive research of a species used in healing, diet and other domains. Most reported studies are illustrative of Phase I Ethnobiological research based on the lack of basic context, emic or ecological detail, or a sense of collaboration with participants or across disciplines. Elements of Phases II, III and IV are evident in some studies highlighting ethnographic context, ecological issues or indigenous knowledge and rights. The extractive character of Phase I research, usually used for bioprospecting purposes, decontextualises plant use and may contribute to the historically poor results from ethno-directed bioprospecting. The widespread marginalisation of the social sciences in bioprospecting research can invalidate the whole research project and in turn ethnomedical plant use itself. A species such as Carissa spinarum L., emerging from Phase I research, can become a mere collection of its phytochemical parts, invalidated if those parts do not meet scientific measures of value. The collaborative character of Phase IV and V Ethnobiology would reward with more ethical and effective research with healing plants.

Part of the book: Medicinal Plants

By Tao Zhang, Gaia A. Scalabrino, Neil Frankish and Helen Sheridan

PH46A, a new chemical entity developed by our group, has shown potent anti-inflammatory activities through various pre-preclinical studies. The aim of this work was to develop and validate a sensitive and robust LC-MS/MS analytical method to determine the levels of PH46 in human plasma, urine and faeces. The linearity (0.5–500 ng/mL for plasma/urine, and 10–2000 ng/g for human faeces), accuracy (within 100 ± 15% for plasma/urine or 100 ± 20% for faeces), precision (≤ 15% CV for plasma/urine or ≤ 20% CV for faeces) and the method’s specificity were demonstrated to be acceptable. No significant matrix effects or carry-over was observed for PH46 and IStd, and the recovery was consistent. About 10- and 100-fold dilutions in control matrix were found not to affect the assays’ performance. PH46 was proven to be stable: at room temperature for >24 hrs in plasma through 3 freeze-thaw cycles, at –20°C for 83 days in plasma/32 days in urine/33 days in faeces, and at –80°C for 154 days in plasma/33 days in faeces. The re-injection reproducibility of PH46 in matrix extracts was at least 239 hrs at 4°C in plasma/25 days in urine/6.5 days in faeces. This method was successfully applied to the pharmacokinetic evaluation of the Phase I clinical studies.

Part of the book: Drug Metabolism and Pharmacokinetics