African medicinal flora in the limelight
In the past few years, African medicinal plants have received considerable attention, and it has been lamented that the documentation of the continent’s species thatare used in traditional
medicine lags behind China and India in terms of ‘internationally recognised phytochemical standards’. This book not only redresses this issue, but is the first to include plants from
the south, north, east and west of Africa. In South Africa alone, there are over 3000 species that are used for medicinal purposes, with over 70% of the Black
African population relying on medicinal flora as part of their primary health care and 84% of clinic patients confirming theirpreference for wild-crafted raw herbal medicines in spite of having
access to western health care.1 Both traditional and Western healing systems are used – many educated Black people retain traditional practices as they are regarded as an
important cultural link to their predecessors. Throughout Africa, plants are viewed as contributors to health; they are also used in religious and cultural ceremonies. The African continent
has a rich biodiversity and this is matched by a commensurateproliferation of medicinal plant use. So the trade of medicinal plants in Africa is substantial, but largely informal, and consists
of plant collectors as well as traders at herbal markets. This book has been assembled by medicinal plant researchers from various African countries who function under the umbrella of the African Association of Medicinal Standards. These researchers
identified the need for the documentation of African herbal products, and emphasise the urgency of the standardisation of African natural botanical products for healing. A format similar to that
used in other continents has been used to provide a herbal monograph for the plants thatare discussed. Each plant monograph includes a general description that focuses on scientific names, botanical
aspects and distribution of the plant species, which is followed by descriptions of ethnobotanical uses, known chemical secondary compounds which function as the main bioactive ingredients, and quality
control measures. The efficacy of medicinal plants depends on the chemical constituents that they accumulate through secondary metabolism – often it is the mixture ofmetabolites that renders them
effective. Plants respond to both biotic and abiotic factors and environmental impacts on secondary metabolism may cause alterations to the chemicals produced. These alterations affect the quality and
safety of herbal medicinal products. Post-harvest processing of material may also influence the effectiveness of medicinal plants, in which case standardisation for commercialisation becomes an important
factor in production. Several phytochemical profilingmethods are used to analyse the chemical constituents of plants, including both simple (thick layer chromatography) and sophisticated chromatographic
(liquid chromatography and gas chromatography) methods, as well as near-infrared spectroscopy. The book is a useful resource, as it outlines pharmacological and clinical studies that have been conducted,
as well as safety information on the various ethnomedicinal products. Several southern African plants feature prominently in the book, including Hoodia gordonii, Hypoxis hemerocallidea (African potato), Pelargonium sidoides (Umckaloabo or African
geranium), Prunus africana (red stinkwood) and Sutherlandia frutescens (cancer bush). Many of the plants discussed in the book are of regional significanceto local communities in Africa
and have not yet found a place in the global natural products sector. However, a few are becoming increasingly important. For example, Pelargonium sidoides is used to manufacture several products
that are commercially significant, traded as Linctagon (South Africa), Umckaloabo® (Europe), Kaloba® (United Kingdom) or Umckan® (Brazil). Overall, the book details methods and procedures that may be employed in studying the efficacy and chemistry of medicinal flora. Many natural product chemists have indicated the need to
conduct extensive phytochemical evaluation of medicinal plants so as to better understand the chemical constituents of African flora.This work should thus find a place in the bookshelves
of both those generally interested in African medicinal plants, as well as those that are interested in the phytochemistry and pharmacology of plants in general.
1. Mander M, Ntuli L, Diedericks N, Mavundla K. South Africa’s traditional medicines industry. Pretoria: Department of Trade and Industry; 2007.
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