Tendwet, Prunus Africana, and the Tree the World’s Pharmacies Depend On

Somewhere on the slopes of Mount Kenya, the Aberdares, or the forests bordering the Mau, an African cherry tree (Prunus africana) is quietly doing something extraordinary.

Its bark contains a complex chemistry that has been used by Kenyan communities for generations to support men’s urinary and prostate health — and that same bark chemistry sits at the centre of a multi-hundred-million-dollar global pharmaceutical industry, an international conservation treaty, and one of the most important conversations in African botanical medicine today: who benefits when Africa’s plants become the world’s medicine?

This post is about Prunus africana — known locally in various Kenyan communities, and the source of one of the active botanical traditions behind our Tendwet formulation. We are going to explore what this tree’s bark actually contains, what the global pharmaceutical industry has done with it, what the patents say, what the emerging cancer research shows, and why the story of this tree matters for how we think about African botanical heritage, ownership, and the future of plant medicine.

What Is Prunus Africana?

Prunus africana — commonly called the African cherry, red stinkwood, or in various Kenyan languages by local names reflecting its long traditional use — is a tall evergreen tree, growing 6 to 30 metres high, found in the montane forests of sub-Saharan Africa and Madagascar. In Kenya, it grows in the Afromontane forest belts of Mount Kenya, the Aberdares, the Mau Forest Complex, and other highland forest areas at altitudes between 900 and 2,500 metres.

The tree’s thick, dark bark is the part of the plant with the longest history of medicinal use. Across many African communities — including in Kenya — bark decoctions have traditionally been used for urinary complaints, prostate-related symptoms in older men, fever, and stomach ailments. This traditional knowledge, accumulated over generations of careful observation, turns out to align remarkably closely with what modern pharmacology has since confirmed.

The Chemistry: What Is in the Bark?

Modern phytochemical analysis of Prunus africana bark has identified several major classes of bioactive compounds, each contributing to its therapeutic profile:

• Phytosterols — particularly beta-sitosterol, the most studied compound in the bark, with documented anti-inflammatory activity in prostate tissue and effects on the enzymes involved in prostate cell growth
• Pentacyclic triterpenoids — including ursolic acid and oleanolic acid, compounds with anti-inflammatory, antioxidant, and emerging anticancer properties- have been studied across multiple cancer types.
• Ferulic acid esters — which appear to inhibit the accumulation of cholesterol in the prostate, a process linked to benign prostatic hyperplasia (BPH)
• Linear alcohols (n-docosanol, n-tetracosanol) — believed to contribute to the extract’s anti-inflammatory and anti-proliferative activity in prostate tissue.
• Atraric acid — a compound that has drawn particular research interest for its activity against the androgen receptor pathway, the same pathway that drives both BPH and prostate cancer

What makes Prunus africana bark pharmacologically interesting is not any single compound acting alone, but the synergy between these compound classes — working simultaneously on inflammation, hormone signalling, cell proliferation, and oxidative stress within prostate tissue. This is the same multi-target principle we discuss in our Segutiet blog series — it is a recurring theme in why traditional African plant medicines are proving so significant to modern pharmacology.

From Forest Bark to French Pharmacy: The Pygeum Story

In the 1960s, French researchers began studying Prunus africana bark extract — sometimes referred to in the pharmaceutical literature by the older botanical name Pygeum africanum — for its effects on benign prostatic hyperplasia (BPH), the noncancerous enlargement of the prostate that affects the majority of men over 60.

The result was a standardised lipidosterolic extract of Prunus africana bark, developed and patented for use in treating prostatic disorders. This extract became the active ingredient in pharmaceutical products sold across Europe — most notably in France, where, according to the patent literature itself, Prunus africana extract became a primary treatment course for enlarged prostate, available in standard 50mg and 100mg capsule doses through pharmacies.

The original patent — filed in the 1970s — describes a specific extraction process: the bark is finely ground and subjected to solvent extraction (the patent describes testing water, methanol, and a range of organic solvents to identify which yields the most pharmacologically active sterol-rich extract), producing a concentrated lipidosterolic extract for use in tablet or capsule form for the treatment of prostatic adenoma.

This patent — and the pharmaceutical products built on it — represent decades of commercial use of an extraction process derived directly from a plant whose traditional medicinal use in African communities long predates any European patent application.

What the Research Shows: BPH and the Emerging Prostate Cancer Story

The Established Use: Benign Prostatic Hyperplasia

The clinical evidence base for Prunus africana extract in BPH is substantial. Multiple clinical trials and systematic reviews have evaluated standardised bark extract for symptoms of enlarged prostate — urinary frequency, weak stream, incomplete emptying, and night-time urination — the same symptoms we discuss in our Men’s Wellness blog on prostate health after 40. The extract has shown measurable improvements in these symptoms, and its mechanisms — inhibiting the inflammatory and proliferative signalling that drives prostate enlargement — are well characterised pharmacologically.

This is the use that is most clinically established and most widely recognised: Prunus africana extract as a phytotherapy for symptomatic BPH, used as a registered herbal medicine in several European countries.

The Emerging Frontier: Prostate Cancer Chemoprevention and Chemotherapy Research

This is where the story becomes genuinely exciting — and where it is important to be precise about what the science currently shows. A growing body of laboratory and animal research is investigating Prunus africana bark phytochemicals specifically for their anti-prostate cancer potential — not just BPH.

The findings from this research, conducted in laboratory cell cultures (including PC-3 human prostate cancer cells) and in animal models, have shown that Prunus africana extracts and their isolated compounds demonstrate:

• The ability to trigger apoptosis — programmed cell death — in prostate cancer cells, through activation of caspase-3, a key enzyme in the cell death pathway
• Antiandrogenic activity, meaning the extract interferes with the androgen (testosterone-driven) signalling that fuels prostate cancer growth
• Antiangiogenic activity, meaning it appears to inhibit the formation of new blood vessels that tumours need to grow and spread
• The ability to alter cell signalling pathways involved in maintaining cancer cell survival and proliferation

In one notable animal study, mice genetically engineered to develop prostate cancer (a model called TRAMP — transgenic adenocarcinoma of the mouse prostate) showed a statistically significant reduction in prostate cancer incidence when fed Prunus africana compared to control animals. Separate laboratory studies using extracts from the root and stem bark of micropropagated Prunus africana plants have demonstrated dose-dependent cytotoxic effects against human prostate cancer cells.

It is important for us to be clear and responsible here: this research represents chemoprevention and chemotherapy potential at the preclinical stage — meaning laboratory and animal studies, not yet validated human clinical trials for cancer treatment. The scientific reviews examining this body of work consistently and explicitly conclude that further preclinical and clinical studies are needed before these phytochemicals could be used for the prevention or treatment of human prostate cancer. Prunus africana is not currently an approved cancer chemotherapy drug.

What the existing patents and approved pharmaceutical products cover is their established use for BPH symptom management — a use directly descended from, and consistent with, the traditional knowledge of African forest communities who have used this bark for generations to support ageing men’s urinary and prostate health.

The Conservation and Equity Story: A Tree Under Pressure

Here is where the Prunus africana story becomes about more than chemistry — it becomes a story about justice, sustainability, and who controls Africa’s botanical wealth.

Because of the global pharmaceutical demand for its bark, Prunus africana has been harvested at scale from wild forest populations across its range — Cameroon, Kenya, Uganda, Tanzania, Madagascar, Equatorial Guinea, the Democratic Republic of Congo, Burundi, and Malawi. In Cameroon — historically the largest exporter — bark harvesting reached an estimated 1,900 metric tons per year during the late 1980s, equivalent to roughly 35,000 trees annually, feeding a global herbal remedy market estimated at around 220 million US dollars a year by the late 1990s.

The consequences for the tree itself were severe. Prunus africana takes around 40 years to reach maturity. Harvesting practices that strip too much bark, or that fell trees entirely, do not allow this slow-growing species to recover. By 1995, the international conservation community responded: Prunus africana was listed under Appendix II of CITES — the Convention on International Trade in Endangered Species— restricting and regulating its international trade due to concerns about overexploitation. It is currently classified as Vulnerable on the IUCN Red List.

Kenya itself has, at various points, restricted exports of wild-harvested Prunus africana bark due to these sustainability concerns — meaning that even as European pharmaceutical companies built profitable, patented products from this tree’s chemistry, the countries where the tree grows have had to grapple with protecting it from the very trade that made it valuable.

Research into the economics of this trade has found something that should give every reader pause: in Cameroon, local harvesters working within protected forest areas have, in some years, earned less than one US dollar per day from bark harvesting — while the retail value of the pharmaceutical products made from that bark reached hundreds of millions of dollars globally. The gap between the value created at the source and the value captured by those who do the harvesting is, frankly, the defining injustice of the global botanical trade — and Prunus africana is one of its most-cited examples.

Why This Story Matters for Tendwet — and for Harriet’s Botanicals

We share this story not to claim that Tendwet is a cancer treatment — it is not, and we want to be completely clear about that. We share it because it illustrates something we believe deeply at Harriet’s Botanicals: African botanical knowledge is not folklore waiting to be validated by Western science. It is often decades — sometimes generations — ahead of where the pharmaceutical world eventually arrives.

The communities that first observed that Prunus africana bark helped older men with urinary difficulties were not wrong. They were early. The pharmaceutical patents that followed, and the prostate cancer research now underway in laboratories around the world, are in many ways catching up to knowledge that African forest communities held long before a single patent application was filed.

Tendwet, our men’s wellness formulation, draws on the botanical traditions of Kenya’s Southern Rift Valley — traditions that, like the Prunus africana story, reflect generations of careful observation about which plants support men’s health as they age, and how. Our approach to sourcing — working with identified communities, documenting traditional knowledge in our cultural archive, and committing a share of proceeds back to herb-source villages — is a direct response to the Prunus africana lesson: that the people whose knowledge and land make a botanical product possible should be partners in its value, not bystanders to it.

What This Means for Men Using Tendwet

If you are using Tendwet for prostate, urinary, or general men’s wellness support, the Prunus africana story offers useful context for understanding why botanical approaches to prostate health are not a modern wellness trend — they are the foundation upon which an entire branch of European pharmaceutical urology was built. The same compound classes — phytosterols, triterpenoids, and related plant chemicals — that anchor patented European BPH medications are part of the broader botanical chemistry tradition that Tendwet draws from in the Kenyan context.

For prostate health specifically, we encourage you to read our companion blog, “Prostate Health After 40,” which covers the practical nutritional, lifestyle, and screening guidance every man over 40 should know — alongside botanical support like Tendwet.

A Final Thought: Protecting What Made This Possible

Prunus africana is Vulnerable. It takes 40 years to grow a tree whose bark the world has been stripping for profit since the 1970s. As consumers — and as a company — we have a responsibility that goes beyond the wellness benefits of any single product. Sustainable sourcing, support for cultivation programmes (rather than only wild harvesting), and fair benefit-sharing with source communities are not optional extras. They are the only way that the botanical wealth of Kenya’s forests — the wealth that produced both Tendwet and, indirectly, pharmaceutical products sold in pharmacies across Europe — will still be here for the next generation.

Explore Tendwet and our full men’s wellness range at harrietsbotanicals.co.ke. Call +254 208 408 888 or visit any of our branches across Kenya.

Important note: This article discusses scientific and historical research into Prunus africana, including preclinical (laboratory and animal) research into its potential role in prostate cancer chemoprevention. This research is at an early stage and has not yet been validated in human clinical trials for cancer treatment. Prunus africana extract is an established phytotherapy for benign prostatic hyperplasia (BPH) symptoms in some markets, but it is not an approved cancer chemotherapy drug. Tendwet is a wellness formulation and is not a treatment for cancer or any other disease. Always consult a qualified doctor for diagnosis and treatment of prostate conditions, including cancer.

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