Phytochemistry of Australiaβs Tropical Rainforest: Medicinal potential of ancient plants by Cheryll J Williams, 2021. CSIRO Publishing/CABI.

It is often remarked that Australia is one of the most venomous countries on the planet (e.g. Carly Williams; Jude Dinely). Which perception is usually down to the weird and wonderful animals that live upon that land (Meg Matthias), or in its coastal waters (Louise Gentle). Understandably, the Australians arenβt that keen on this βmythinformationβ* being all that most people know about their homelandβs amazing wildlife (and, anyway, Mexico β apparently β has more animals that are venomousβ¦). So, I wonβt be banging on about Australiaβs fauna here. Instead, Iβll concentrate on that countryβs flora, and take a look at Cheryll Williamsβ Phytochemistry of Australiaβs Tropical Rainforest [hereafter PATR] (which book is here appraised).
Although some of Australia’s plants can be as dangerous as its animals,** the focus of PATR is much more on the healing properties of its benign rainforest botanics, i.e. concentrating upon the plants’ life-giving potential rather than any life-shortening propensity. But, featuring some plants whose poisonous nature are well-known β e.g. the aptly-named Australian poison walnut tree (Cryptocarya pleurosperma) (which contains a curare-like βprincipleβ), and no doubt many more plants whose toxicity are as yet unassessed β Williamsβ Australian pharmacological journey reminded me of two famous quotes. First is one attributed to Paracelsus (anuka*** Philippus Aureolus Theophrastus Bombastus von Hohenheim) (Spyros Michaleas et al., Toxicology Reports 8: 411-414, 2021; https://doi.org/10.1016/j.toxrep.2021.02.012), βthe dose makes the poisonβ (Philippe Grandjean, Basic Clin Pharmacol Toxicol. 119(2): 126β132, 2016; doi: 10.1111/bcpt.12622). Second is Friedrich Nietzscheβs βwhat does not kill me makes me strongerβ. Both capture not only the potential dangers in discovering and testing new plant-derived treatments for human conditions but also the empowerment that can come from a successful outcome.
Whilst any life-limiting potential of the rainforest flora is reason to proceed with caution in attempts to harness its power to do good, itβs not a reason to ignore it: There are many stories of the benefits that have come from appropriate use and exploitation of botanics elsewhere in the world. Although well-documented, and probably familiar to many readers, several of those tales are included in PATR. As a good example of that itβs worth highlighting the case of nutmeg. Fragrant nutmeg (Myristica fragrans), originally sourced from the Spice Islands (now a part of Indonesia), has a very long history of use as a medicinal plant by humans. That compendium of accomplishments is comprehensively catalogued in PATRβs Table 7.0 βMedicinal uses of fragrant nutmegβ. Occupying six pages, that data display is just a small part of the 40+ pages of Chapter 7 that are devoted to nutmeg and mace. Why are so many pages of PATR taken up by a species that Williams informs us is not native to Australia? In the absence of context or justification, it would be easy to dismiss their inclusion as some sort of text-padding. But, that is not the case; those success stories are presented as inspiration and justification to take more interest in the Australian flora, particularly species that are closely related to sources of plant-produced pharmaceuticals of proven value from other countries. The rationale for that view lies within the concept of chemical taxonomy [where evolutionarily-related species are likely to contain similar cocktails of chemical compounds, which may have medicinal value, e.g. Ram Singh, 2016 (J Med Plants Stud 2016;4(3):90-93)], which is an important theme throughout the book. In the particular case of nutmeg, although fragrant nutmeg is not an Australian native, three other Myristica species areβ¦
Although it takes a lot of time and money to prove the pharmaceutical worth of just a single plant-derived product [and Williams provides ample evidence of the long and winding road that leads to the door of successful drug discovery], itβs a journey that should be taken. After all, in humanityβs battle against the dreaded dual demons of disease and debilitation (and untimely death), we need as wide an arsenal of effective drugs and medicines as possible. Fortunately, that task has become a lot easier with Williams having already done a lot of the hard work in highlighting species that are worthy of further investigation. And now that PATR has been released into the community it is surely indefensible to continue to ignore the pharmaceutical possibilities of indigenous Australian plants.
However, with a depressingly long list of factors that threaten the survival of rainforest plants β covered in-depth and breadth by Williams β itβs a desperate race against time to make the necessary progress that’s sorely-needed progress thatβs essential to identify, catalogue, and assess each speciesβ pharmaceutical properties. But, as Williams also reminds us, any exploitation of that resource should be carried out in a way that respects nature and conserves the rainforest habitat for the future. Books such as PATR are therefore very important, and should also serve as a βwake-upβ call to everybody who values our so-called βnatural capitalβ. Although the land of Australia was once known as terra australis incognita, thanks to PATR there is now no longer a need for the formidable pharmaceutical potential of its rainforest vegetation to be βflora incognitaβ.
Some other thoughtsβ¦
The approx. 550 pages of PATR‘s main text are well-written and profusely illustrated β with almost all images in colour, and with informative legends (which is always nice to see). With at least 3600 references(!!) (which are cited in-text by numbers), it is clearly a work of great scholarship. But, not only that, it also appears to be a true labour of love that is thoughtfully-written, and probably as up-to-date as its 2021 publication date permits with mention of Australiaβs devastating bush fires of 2020. Mindful of the cultural heritage associated with the Australian flora and its extensive and ancient use by the indigenous peoples of that land, there is an important cultural sensitivity warning at the front of the book. This is particularly apt in relation to some of the wording in the quoted text regarding Bunya pine feasts. Many instances are cited in PATR where modern science has vindicated traditional uses of rainforest plant remedies, further emphasising the untapped potential of these plants (and the wisdom of the Ancients).
Whilst the larger part of the book is devoted to angiosperms and gymnosperms (Regina Bailey), other members of the plant kingdom, e.g. ferns and tree ferns (Gregory Moore), whisk ferns (Matt Candeias), and lycopods (tassel ferns and clubmosses) (Joe McAuliffe) get a good mention. In keeping with the bookβs title, all of the plants covered are to be found within Australiaβs native rainforest, which is found in the east of the country and extends from the northern tropics (Cape York, in the northern state of Queensland) to the southern island state of Tasmania. Although we acknowledge that the present-day flora is the product of evolution, itβs nice to know that some plants havenβt changed all that much since they first appeared on the planet. In that regard, and in keeping with PATRβs sub-title, Medicinal potential of ancient plants, itβs nice to be reminded that the Australian rainforest is home to some ancient relics of the palaeoprehistoric flora of Gondwana.
Although the book contains a wealth of information β e.g. on botany, ethnobotany, medicinal uses of plants, pharmacology, biochemistry, taxonomy, biogeography β its emphasis is the preciousness, uniqueness and rarity of the Australian rainforest flora (and the medicinal secrets they may hold). PATR ranges between hard-core biochemistry and pharmaceutical science on the one hand, and the personal narratives of traveller-explorers, naturalists and indigenous peopleβs ethnobotanical testimonies on the other. But, at its heart is tremendous respect for the rainforest itself and the valuable resource that its plants represent, which β if used wisely and sustainably β could help alleviate a lot of human suffering.
PATR is a book with several uses. It is certainly a phytopharmacology reference source [and therefore a tome to βdip intoβ as-and-when; it would be extremely hard-going if you chose to read it in one single sitting as a traditional text]. Itβs also something of a love story for the medicinal potential of the rainforest with plenty of lovely passages written by the author quoting other notable commentators. And, in part itβs a botanical textbook with its frequent mentions of plant biology β e.g. bioaccumulation properties of waterlilies, Lotus thermogenesis, Aristolochia pollination mechanism, and frequent background information on plant evolution and palaeoenvironments. Accordingly, many different audiences will derive value and benefit from this remarkable book. And, not just plant lovers, entomologists should also find much to interest them (e.g. the section on Butterflies of literature, legend and medicine, and the numerous butterfly pictures throughout the book).
No, PATR isnβt βperfectβ β e.g. it could do with more references in several places (mainly for the more general plant biological information provided), sources for some of the figures are not stated, images of flowers and fruit would greatly benefit from scale bars, in several sentences single words are bizarrely missing (which seems to be a consequence of an attempt to constrain narrative to fully fit the full-justified two columns of text per page layout the book uses), and Appendix table columns 4 and 5 appear to be erroneously identified as 3 and 4 in the text on p. 530. But, its imperfections are pleasingly minor, and far-outweighed by its positives.
By now, you may have formed the view that I like PATR. I do. So much so that thereβs so much more Iβd like to share with you about the book (e.g. the very particular mal-de-meric role played in the D Day landings of the Second World War by a drug derived from Australian plants, and the plant substituted for quinine during the American Civil War of 1861-1865, the identity of the plant known as Cornish pepper (because it was used as a spice in Cornwall (a county in the UK)), and the recipe for spruce beerβ¦). But, my task here is to appraise the tome, not to give away too many of its insights and interesting facts. Thatβs where it is up to the reader to do his/her bit and discover their own βtake-home messagesβ. And that I encourage you to do.
Summary
Lack of knowledge about the value of rainforest plants was a large part of the authorβs motivation for writing the book. PATR makes it clear that there is no longer any excuse that we lack that knowledge (although we can always do with moreβ¦): The pharmaceutical potential of the Australian rainforest flora is clearly laid-out in Cheryll Williamsβ Phytochemistry of Australiaβs Tropical Rainforest, which is a remarkable book.
* This is a word Iβd thought Iβd invented. Sadly, thatβs not so; itβs already in the dictionary and means what I intended βmyβ neologism to mean: βinformation which is widely held to be true but which is in fact flawed or unsubstantiated; common knowledge based on hearsay rather than factβ, or βwidely held and promoted but false information that has taken on a mythic qualityβ, or βfalse information, when seen as having its own mythology or being believed in like a myth would beβ.
** Astute readers of this item will notice that Iβve said very little about dangerous Australian rainforest plants. To find out what they are, youβll need to read the book(!).
*** anuka is an initialism (and maybe also an acronym (when anuka is officially defined as a wordβ¦)), which means βas not usually known asβ¦β. And which therefore is opposed to the more familiar βakaβ (meaning βas known asβ). Now, Iβm pretty sure that βanukaβ is something I have inventedβ¦
Thank you for your kind words, it was a long journey to write this and your appreciation is truly heartening.
Regards, Cheryll
It was my pleasure!
I wish you all the very best in your continuied endeavours to protect this precious habitat.
Cheers,
Nigel Chaffey