Volg ons op Facebook

The medicinal use of plants

Written by  Dale Barber
| in Tuin
| August 4, 2014

It is difficult to imagine a time when we did not have access to after-hours pharmacies and the convenience of pharmacies in our local supermarkets and shopping centres.

Nowadays, medicines and pharmaceuticals are readily available, and in some instances we even have prescribing pharmacists and dispensing doctors. With all this ready access, one would think there should be fewer sick people around. This however, is definitely not the case.
Unfortunately, this abundance and easy access to medicines have come at a hefty price - and I don’t only mean rands and cents. Many of us are guilty of not completing a course of medicine, as we tend to get remedies to alleviate the symptoms, stronger pain killers, and finally the medicine required to deal with the actual problem itself. With all of this we tend to feel better (symptomatic relief) before we’ve actually been cured, and thus stop taking our meds. The result is more virulent and drug resistant diseases, and hey presto, before we know it, there are a greater number of killers out there.
      An interesting fact is that at least fifty percent of all medications are still derived from plants. Even a lot of artificially synthesised compounds are copies of compounds occurring naturally in a wide variety of plants. South Africa is blessed with having one of the most diverse floras in the world, so it is not surprising to find that a lot of our plant species have medicinal properties. I can still remember how my Ouma – now many years ago –  had a natural remedy for every conceivable ache and pain. Ja, those good old fashioned boere remedies that had their origins in the knowledge of the South African indigenous peoples. Untitled-1      It is also sad to know that in this age of knowledge, where information is so readily available; there has been a decline in the old knowledge. Those old remedies and cures, passed on from generation to generation, from time immemorial. Maybe we should give Google a rest and talk to our grandparents to try and regain some of this valuable knowledge before it is too late.
      They say we are what we eat, and I have therefore decided to take a look at some of the herbs and vegetables we eat every day, to see what medical benefits they have. So, take a minute or two - some of these plants may just surprise you!

Onion (Allium cepa)

      Few can argue that this pungent bulb (and its close relative, garlic) is a key basic ingredient of virtually all of the world’s great cuisines. The onion as we know it today is a cultigen which probably evolved as early as the Bronze Age, probably in Iran or Afghanistan, from where it soon spread to most of the classical Old World.
      By Roman times, onions were consumed as a staple by the common people in many parts of the Empire, largely raw, and presumably as a large sweet, mild cultivar. As a matter of fact, the English word “onion” is ultimately derived from the Latin “unio” (single white pearl). The Romans – and after them, their European colonies – were the great disseminators of the plant around the world.
      Already by Roman times the breath-tainting stigma associated with raw onions was established: it was a coarse food, avoided by upper classes (Apicius, the famous Roman cooking writer, for instance hardly includes onions in his recipes). In contemporary Egypt, the priestly caste was forbidden to eat onions. Similar taboos persist in India for Brahmans and Jains.
      And with this we have also arrived at the miracle of the onion. For, as anyone knows, as soon as the raw bulb is cut, it releases a pungent smell and an eye-stinging substance. In nature, this is meant to discourage organisms from consuming it. But exactly this natural defence has been harnessed by humans to our great culinary and also medicinal advantage.
The pungent smell and eye-stinging properties are due to the enzymatic breakdown of sulphur-containing substances within the damaged tissues. In interaction with air, these spontaneously convert to volatile disulphides (a tip: chill your onions before chopping – chilling reduces chemical volatility). However, when heated, these substances become sweet and aromatic, providing umami (“mouthfullness”) to food, and thus contribute much to the onion’s value as an aromatic vegetable.
       At the same time, these disulphides readily form disulfide bonds with SH-group proteins, and are thus able to alter their biological activities. This gives raw onion (juice) good anti-microbial properties, as well as a number of medicinal applications. Of these, its ability to inhibit blood-clotting (and hence prevent thrombosis) is probably the best known. The raw bulb or juice is also used to treat minor digestive disturbances and various chest complaints. Juice rubbed onto insect stings helps alleviate the pain. More recently, clinical trials have also indicated that substances derived from onions may be useful for treating weight loss and arteriosclerosis. So there then: eat well, and live long!

Chilli (Capsicum species)    

      Chillies originated in the Americas, and were brought to Asia by the Spanish and Portuguese in the 16th century. The compound which makes the old chilli as hot as hell, is capsaicin. Chilli peppers have been part of the human diet since approximately 7 500 BC, in Mexico and parts of South America. We all know how chillies have influenced world cuisine – from the central Americas, through Asia, to Europe.
      The medicinal qualities of chillies are related to the reduction of blood pressure, and extracts are commonly used in creams to ease arthritis and shingles. In Mexico chillies were used to treat toothache.
      In 1653 the English botanist Nicholas Culpeper wrote “A preliminary warning: Violent plants and fruits under the influence of the planet Mars. The vapours that arise from the husks and pods will so pierce the brain by flying up through the nostrils as to produce violent sneezing and provoke sharp coughing and cause violent vomiting. Cast into a fire it raises grievous strong and nauseam vapours while eating the pepper proves dangerous to life. Nevertheless, when corrected of their evil qualities, they are of considerable service.”
      Culpeper recorded  these services as: the expelling of kidney stones, helping the dropsy, helping with birth pains, removal of spots and freckles, softening of the skin, curing of halitosis, toothache, and ‘hysteria and other female disorders’, as well as healing the bites of venomous beasts. In short, the chilli was a miracle cure!  

Lavender (Lavandula species)

      These well-known perennial shrublets of the mint family with their spikes of fragrant purple-blue flowers are indigenous to the Mediterranean region. Our English word is apparently ultimately derived from the Latin “lividus” (bluish, livid), but some sources suggest “lavare” (to wash) as another possible root. This is not implausible, as the Greeks and Romans both prized its long-lasting clean, fresh fragrance as a bath additive. And its scent is prized to this day.  A number of species are commonly grown today, of which mainly L. angustifolia, L. latifolia (broad-leaved), L. dentata (French) and L. stoechas (Spanish). Apart from being favoured garden subjects, lavender is also cultivated as a crop, mainly for its essential oil (1-3%) which finds massive application in the perfume and cosmetics industry, but which also has numerous medicinal applications.
      The anti-microbial efficacy of lavender was noticed (if not understood) as early as the 14th century, during the time of the Great Plague, when it was observed that the glove makers of Grasse (Provence) who traditionally rubbed their product with lavender oil, were largely untouched by the plague. Nowadays, this strong anti-microbial action has been clinically proven, and the oil’s ability to help disinfect and heal topical cuts and wounds is well established. In addition, the oil is also very effective in treating burns and stings.
      And for those of us often having to count sheep, lavender is an old friend. The flowers (and oil) have an established sedative, calming effect, and is also used in aromatherapy to treat headaches, tension and emotional upsets.

Untitled-2

Agapanthus africanus

      Agapanthuses are found in many gardens and the striking display of their purple flowers clustered on a tall slender stalk makes a bold visual statement. Medicinally the plant is used as a decoction administered orally as an ante- or post natal medicine. The traditional belief is that it aids with the movement of the baby. It is a mild purgative and helps ease a difficult labour. It also has anti-inflammatory and anti-hypertensive properties.

Agathosma betulina (Buchu)

      Buchu is an attractive shrub with small white or purple star-shaped flowers. Although it has found its way into a number of gardens, buchu is better known for its medicinal properties. Buchu is part of the cultural heritage of the Khoi and San people: the dried leaves were mixed with sheep fat and rubbed onto their bodies for both cosmetic and anti-bacterial protection. The leaves were also chewed to relive stomach cramps. The early Dutch settlers steeped the leaves in brandy, also as a remedy for stomach problems. Buchu vinegar was used for the cleaning of wounds. The essential oils are generally used for their antiseptic and anti-diuretic properties.
Artemisia afra (African wormwood or Wilde als)
      This aromatic plant is a perennial shrub – the feathery leaves are finely divided and have a greyish-green colour. Wilde als is one of the most widely used traditional medicines in South Africa, used for treating numerous ailments, mainly coughs, colds, and influenza. It is also used to treat fevers, colic, headaches, earaches, malaria, and intestinal worms.
Bulbine frutescens (Bulbinella)
      Bulbinella is a small shrub with a woody stem and succulent leaves. The flowers are usually yellow, but a bright orange variety is a popular garden cultivar. Medicinally, the succulent leaves are used as a treatment for wounds, burns, rashes and itches.

Carpobrotus edulis (Sour fig or Perdevy)

      This perennial ground cover has an attractive yellow flower and is used horticulturally as a soil stabiliser. Ripe fruits are commonly sold in the Cape, and are popular for making jams and curry dishes. The leaves are triangular, thick and fleshy, and are the part most commonly used for medicinal purposes. Traditionally used to treat infections of the mouth and throat, it is taken orally to treat dysentery, digestive troubles, tuberculosis, and as a diuretic. The sap is applied topically to treat eczema, burns and wounds.

Clivia miniata (Bush lily)

      The clivia is a popular garden plant with dark green, strap-shaped leaves. The showy orange flowers arise from the same point on a tall flower spike. They are also used as pot plants throughout the world as they are shade loving perennials. Medically, the whole plant is used. The Zulus use the rhizomes to treat fever. The plant is also used to help with childbirth, as a snakebite remedy, and it is claimed to relieve pain. However, clivias are also known to be toxic due to the presence of numerous alkaloids – thus continued use should be discouraged.
Erythrina lysistemon (Common coral tree)    
      This well-known tree can easily be recognised by its thick thorny branches and bright red flowers. The toxic seeds are also known as lucky beans – they are red with a black dot. Medicinally the bark and crushed leaves are used to treat sores, wounds, abscesses, and arthritis. Open wounds are treated with the powdered burnt bark. Leaf infusions are used as eardrops to relieve earache.

Pelargonium

      These popular garden plants made their way to Europe in the 1600s. They are commonly seen as bedding plants, and are also used in herbaceous borders. Pelargoniums are used in the perfume industry and are distilled for their scent. The most commercially important pelargonium is the species graveolens, or rose scented geranium. Its aromatic leaves were first used medically in 1687 as a treatment for colic and nephritis.
      Traditionally, the leaves of P. betulinum were steamed and the vapours were used to treat coughs and chest problems. P. odoratissium was used as a cardiac stimulant, and the whole of P. ramossissimum as a nerve tonic, and a cure for colds and tuberculosis. The leaves of several species were used to make poultices for treating wounds.
      Well now, I think I may have bored you to tears with plant after plant. I could go on and on as there are approximately three thousand medicinally-used South African plants. Whilst reading and researching plants, I have found that even though a lot of plants are used traditionally, there are not always a lot of scientific papers reinforcing the traditional use of these plants. So I have a new-found respect for the knowledge possessed by our traditional healers.
      However, like with all medicines, care must be taken in the diagnosis and dispensing of these remedies.

Untitled-3