By Maryann Readal

Madagascar, an ancient island off the coast of East Africa, holds a treasure of unique plants growing in its diverse ecosystems. The island is the fifth largest island in the world and is about 1.5 times the size of California with a population of about 30 million (World Bank Group, 2024). It separated from Africa millions of years ago creating its own unique haven for plants and animals. According to a recent report, there are more than 12,000 known plant species with at least 2,500 still to be discovered or documented in Madagascar (Critical Ecosystem Partnership Fund, 2024). Ninety six percent of these plants are endemic. It is estimated that more than 2,300 of the known plants are used medicinally by the Malagasy people. Ninety percent of these medicinal plants have not been commercialized (Rabarison, 2015).

The country’s towns and villages are remote, and their economic disadvantages are profound with 81% of its population living below the poverty rate of $2.15 per day (World Bank Group, 2024). Out of necessity and because of easy access to plants, the Malagasy learned to put their plants to good use. Even so, how the people discovered plants that heal, as well as supplement their diets, is truly a wonder. There is still much to be learned about native plant use in countries such as Madagascar.

A 2013 study (Razafindraibe, 2013) showed that Malagasy women and healers are the major providers of health care in their communities and that plants that can be used for digestive, reproductive, prenatal, and postpartum health are the most frequently used plants. This observation was reinforced by National Park Guide, Ms. Ursula Kalo, who commented that many Madagascar plants are used for women’s health, fertility, contraception, or for male virility. In Madagascar, 70% of plant-based medicines are made from an infusion of plant leaves. And as documented in the literature, the same plant used by one ethnic group may be used for different health reasons by another group.

This article will highlight a very small sampling of the medicinal plants I discovered during a visit to just one of the country’s rich rainforests, the Masaola National Park, the largest protected area in Madagascar and considered to be a biodiversity hotspot.

Normally, we consider basil to be a culinary plant. However, in Madagascar, clove basil (Ocimum gratissimum), also known as African basil, is used as a medicine to cure many illnesses from diarrhea to fungal and bacterial infections, inflammation, and pneumonia. It is also used to treat postpartum infections. Another plant, whip vine (Flagellaria indica), is used to make baskets and thatched roofs. In addition, the plant’s stem is used to make a contraceptive, and the boiled root is used as a health tonic for male virility. Another plant, Commelina madagascarica, known as dayflower/spiderwort, is used by some Malagasy peoples to treat male and female infertility, and according to Ms. Kalo, “Helps to calm a woman down to have a baby.” It is also used to induce abortion. For many gardeners in the United States, the Asiatic dayflower (C. communis)—a relative of the powerful C. madagascarica—is considered a weed!

Another plant used to treat sexual health is Zanthoxylum tsihanimposa, or prickly ash. It is used to treat erectile dysfunction and venereal disease, as well as malaria and wounds. Cinnamosma madagascariensis treats complications of childbirth, in addition to erectile dysfunction and tooth decay. The leaves of Afromomum angustifolium, Madagascar cardamom, are cooked with rice and given to new mothers to help with lactation. And interesting to note, the stem of the vanilla orchid (Vanilla madagascariensis), which drapes trees in the rainforest, is used to treat erectile dysfunction and is also used as an aphrodisiac. Incidentally, Madagascar produced three million tons of vanilla in 2022, making it the largest exporter of vanilla in the world (World Population Review, 2024). Madagascar is also the world’s principal supplier of cloves (Syzygium aromaticum) and ylang ylang (Cananga odorata).

Other plants observed outside of the rainforest were some that we grow in our gardens. Lantana camara is one of them. This lantana is used by the Malagasy people to treat wounds, hypertension, malaria, and diarrhea. Catharanthus roseus, rosy periwinkle, is another plant that we grow in our gardens, primarily as an ornamental. It is native to Madagascar and is used to treat leukemia and other cancers. Turk’s cap (Malviciscus arboreus), while having only minor medicinal value, is hung outside the house announcing that someone has died.

There is considerable concern that as underdeveloped countries, such as Madagascar, catch up to the rest of the world, much ethnobotanical knowledge will be lost. This will negatively impact the discovery of new drugs to treat illness. Madagascar is considered a biodiversity hotspot, and there is potential for the natural riches of its ecosystems to be overused and depleted as the country moves toward modernization. As a result, beneficial and unique plant species could be lost.

Interestingly, I did discover that there is a difference between published information about medicinal plants in Madagascar and how they are used by some of its indigenous people. The literature suggests that very little research has been done on the ethnomedical practices of the eighteen ethnic groups in Madagascar and that more of these unique practices need to be documented before the information is lost (Rakotondrafara, 2018). As a result of this trip, I am convinced that there is still much to learn about medicinal plants in many of the underdeveloped countries of the world.

Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.

Photo Credits: 1) Madagascar rainforest (Wikimedia Commons, unknown photographer); 2) Village women selling spices and straw products (Ursula Kalo); 3) Clove basil (Ocimum gratissimum, Wikimedia Commons, Nivo H. Rakotoarivelo) and whip vine (Flagellaria indica, Wikimedia Commons, Patrice Antilahimena); 4) Dayflower (Commelina madagascarica, Wikimedia Commons, Nadia Volomboahang), prickly ash (Zanthoxylum tsihanimposa, Wikimedia Commons, Tabita Randrianarivony), and vanilla (Vanilla madagascariensis, Wikimedia Commons, Richard Randrianaivo); 5) Lantana (Lantana camara, Maryann Readal) and rosy periwinkle (Catharanthus roseus, Maryann Readal); 6) Turk’s cap (Malviciscus arboreus, Maryann Readal).

References

Critical Ecosystem Partnership Fund. 2024.  Madagascar and Indian Ocean Islands—Species. Accessed 10/3/24. https://www.cepf.net/our-work/biodiversity-hotspots/madagascar-and-indian-ocean-islands/species

Rabarison, Harison. 2015. National biodiversity and action plans 2015-2025. Accessed 9/4/24. https://www.cbd.int/countries?country=mg

Rakotondrafara, A., et al. 2018. Ethnobotany of medicinal plants used by the Zafiminary clan in Madagascar. Accessed 10/3/24. https://www.phytopharmajournal.com/Vol7_Issue6_06.pdf

Razafindraibe, M., Kuhlman, A.R., Rabarison, H., et al. 2013. Medicinal plants used by women from Agnalazaha littoral forest (Southeastern Madagascar). J. Ethnobiology Ethnomedicine Vol. 9, Issue73. Acccessed 9/26/24. https://pubmed.ncbi.nlm.nih.gov/24188563/

United Nations. N.D. Madagascar–Country profile. Accessed 10/3/24. https://www.cbd.int/countries/profile?country=mg

World Bank Group. 2024. World Bank in Madagascar. Accessed 10/9/24. https://www.worldbank.org/en/country/madagascar/overview

World Population Review. 2024. Accessed 9/4/24. https://worldpopulationreview.com/country-rankings/vanilla-production-by-country