On the site here, and at The Moringa Home Page, I talk a lot not only about “moringa” Moringa oleifera, but also about the other 12 species of the genus. This is bewildering—which one should you grow and use for your intended application? The short answer is Moringa oleifera, no contest. Though we are still studying the other species, all research shows that M. oleifera hands down wins out over the other species in terms of leaf nutritional yield and quality, antioxidant activity, potential glucose regulatory activity, antibacterial qualities, growth rate, leaf and fruit yield, oil edibility and quality, and a host of other aspects of interest. So that’s the short answer: all evidence points to using M. oleifera for any given application. If you want more detail, keep reading!
To depict the inclusion of one level within the other, these classification systems are often written with indentation, with more indented levels included in the ones above:
To use our cat example, we would write:
Family names are written with an uppercase and not in italics (Moringaceae). Genus names are written in italics and with an initial uppercase (Moringa), and species names (also called epithets) are written in lowercase and in italics (oleifera). So Moringaceae or Moringa Oleifera are not correct. It’s Moringa oleifera in the family Moringaceae. After the first mention of the genus name all spelled out, it’s common then to abbreviate, i.e. M. oleifera. So the classification of Moringaceae is as follows:
Visit the Moringa Home Page for info on the 13 species, and visit the publications page too.
Here is a brief summary regarding the uses of the 13 species.
I gave a brief summary of M. oleifera properties in the first paragraph, and so won’t repeat it here. I will mention, though, that it is natural that M. oleifera should be the most useful species. With thousands of years of use, people have kept the best variants and grown them preferentially over less desirable ones. Through this selective breeding, they have probably enhanced the desirable traits. So, even if another Moringa species might exceed M. oleifera in one or another trait, M. oleifera is the best all around Moringa species by far. Let’s look at the other species to see why. We’ll start with the species known to be edible in some way, and then turn to the others, which are used medicinally by local people but not eaten, and some of which are even reputed to be poisonous.
Besides M. oleifera, three species are known to have some degree of edibility, M. stenopetala, and to a lesser degree M. concanensis and M. peregrina.
Moringa stenopetala This is the second most-cultivated species of Moringa. It seems to be found native only in a handful of localities around Lake Turkana, in the Great Rift Valley of northwestern Kenya and southeastern Ethiopia (see post on the discovery and description of Moringa stenopetala). Slightly to the northeast, it forms part of a fascinating system of permaculture agroforestry in southern Ethiopia in the region of the Konso people. This area is at the upper elevational margin of the dry tropics, around 1600 meters above sea level. People there grow annual vegetable crops in the rainy season, but plant Moringa stenopetala trees abundantly in their towns. Moringa stenopetala has a very large, water storing trunk and holds on to its leaves well into the dry season. These are eaten by the Konso as an important dry season food (see Jahn 1991, Förch 2003, Jiru et al. 2006). In some analyses, Moringa stenopetala has a higher protein content than M. oleifera. Does this mean you should grow M. stenopetala instead? It certainly can’t hurt to try growing them, and they are for sure wonderful trees, but for most applications, M. oleifera is still preferable. For example, our research (Fahey and Olson in preparation, Fahey and Olson unpublished) shows that the “anticancer” (phase 2 detoxication enzyme inducing) activity of M. oleifera is among the highest recorded, while that of M. stenopetala is non-existent. Though its growth rate and yields are impressive, M. stenopetala grows more slowly than M. oleifera and its yields are lower. Its seed yields are lower and the thick, spongy seed coat of M. stenopetala makes it even harder to get the oil out, with lower yields and, apparently, lower quality seed oil and much lower water clarification properties. Moringa stenopetala leaves have a tougher texture to eat than the very soft leaves of M. oleifera. Whereas M. oleifera grows as a rangy pole during its first year, M. stenopetala tends to form many stems from the base, forming a huge shrub if you don’t shape it aggresively. So, based on what we known now for its antioxidant properties, higher growth rate, more palatable leaves, and better oil yield, M. oleifera is the moringa of choice.
Moringa concanensis This is the closest living relative of M. oleifera. It is native throughout the lowland dry tropics of eastern and southern Pakistan, much of India, and a few small localities in Bangladesh. It looks somewhat like M. oleifera and is often confused with it. It has thicker outer bark than M. oliefera and bipnnate rather than tripinnate leaves. The young fruits, and sometimes leaves and flowers, are occasionally eaten locally (e.g. Arinathan et al. 2007), but in general this species is regarded as medicinal, including intervening in cholesterol levels, diabetes, and parasite infections, much like other species of Moringa (e.g. see Anbazhakan et al. 2007, though their description of the species seems at odds with its morphology).
Moringa peregrina is, in turn, the closest living relative to M. oleifera+M. concanensis (Olson 2002). It is a slender trunked or bushy tree with wispy leaves that drop their leaflets at maturity. So the mature leaves are made up of just the naked, woody axes, not something you would want to eat. The oil contained in the hard-shelled, wingless seeds is laboriously collected and saved for medicinal use, at least in Oman, where it is reportedly taken by the cupful for stomach complaints. The only edible part seems to be the tubers of young plants, which are roasted and eaten. I haven’t tried them yet, but will report on it when I do.
Only M. oleifera, M. stenopetala, M. concanensis, and M. peregrina are known to have any degree of edibility. The other species are all used medicinally locally, though. I summarize them here geographically:
Madagascar and southwestern Africa: Moringa drouhardii and Moringa hildebrandtii are classic tomb ornamentals in southern and western Madagascar (see Olson and Razafimandimbison 2001). The bark of the trees is often scraped and gouged. Local people told me that they use the bark in decoctions for bronchial complaints. I asked them if they ever ate the leaves or the seeds, and they told me that they are poisonous. Moringa ovalifolia, from Namibia and Angola, also seems to be used medicinally but never as food.
Northeast Africa: Moringa arborea, M. borziana, M. longituba, M. rivae, and M. ruspoliana are all used medicinally. The roots all seem to be used to treat intestinal parasites in goats and camels, and skin afflictions in animals. Moringa pygmaea is so geographically restricted and so poorly known in general that, while it might be used similarly, there is no documentation of this. No part of any of these species is eaten.
The conclusion from all of this is that the best bet for nutrition, chemoprotective, or edible oil production, the best bet has been and is still Moringa oliefera. However, there is much research to be done. Very little is known about most species. Nice comparative studies are being done on the oil quality of various species (more on this in a later post), and the International Moringa germplasm collection is designed to be used for just this sort of comparative work. With more studies, and with any luck, the list of the “best” moringas for a given application will get longer.
Arinathan, V., V. R. Mohan, De Britto, A. J., and C. Murugan. 2007. Wild edibles used by Palliyars of the western Ghats, Tamil Nadu. Indian Journal of Traditional Knowledge 6: 163-168.
Förch, W. 2003. Case study: the agricultural system of the Konso in south-western Ethiopia. FWU Water Resources Publications 2003:1, University of Siegen, Germany, http://fwu.fb10.uni-siegen.de/bkd/FWU_WRP.htm
Jahn, S. A. A. 1991. The Traditional Domestication of a Multipurpose Tree Moringa stenopetala in the Ethiopian Rift Valley. Ambio 20: 244-247.
Jiru, D,. K. Sonder, and L. Alemayehu. 2006. Leaf yield and Nutritive value of Moringa stenopetala and Moringa oleifera accessions: Its potential role in food security in constrained dry farming agroforestry system. Presented at the conference Moringa and other highly nutritious plant resources: Strategies, standards and markets for a better impact on nutrition in Africa. Accra, Ghana, November 16-18.
Miller, A. G., and M. Morris. 1988. Plants of Dhofar. Office of the Adviser for Conservation of the Environment, Diwan of the Royal Court, Sultanate of Oman.
Olson, M. E. 2002. Combining data from DNA sequences and morphology for a phylogeny of Moringaceae. Systematic Botany 27: 55-73.
Olson, M. E., and S. G. Razafimandimbison. 2000. Moringa hildebrandtii: A tree extinct in the wild but preserved by indigenous horticultural practices in Madagascar. Adansonia sér. 3 22(2) 217-221.