Beating pimples, boils, bleeding with local herbs
RESEARCHERS have verified the traditional uses of two local herbs in treating acne (pimples), bleeding, intestinal worms, hypertension, and other diseases. CHUKWUMA MUANYA reports.
Researchers have found some local herbs effective in treating acne or pimples, eczema, boils, wounds, diarrhoea, intestinal worms, hypertension, bleeding, and dysentery by reducing the growth or killing the disease-inducing bacteria. Top on the list are two Nigerian herbs- Euphorbia hirta and Eclipta alba.
Also, cosmetic compositions comprising an extract of Eclipta alba have received a United States Patent 5559146. The cosmetic preparations according to the invention are particularly effective on brown or black melanin-based hyperpigmentations related to scars or resulting from a photosensitizing agent, as well as on the hyperpigmentations of senile lentigo.
Euphorbia hirta locally known as ogwu ngwo (eczema drug) in some Eastern parts of Nigeria is used locally to arrest bleeding in the event of an injury. Leaves of Euphorbia hirta are used in traditional medicine for the treatments of boils, wounds and control of diarrhoea and dysentery.
Commonly called Asthma herb, Euphorbia hirta belongs to the plant family Euphorbiaceae. It is called malnommŽe in French. In Nigeria, it is z’gban (that which grows thorns) in Edo, endamyel in Fula-Fulfulde, n——n˜n kœrc’y‡‡ (dove's milk) in Hausa, ˜b ˆn (ground fig tree) in Igbo (Asaba), ˜b ˆn (ground fig) in Igbo (Okpanam), ba ala in Igbo (Owerri), bou ob’r’ma (the fruit) in Ijo-Izon, akun esan in Yoruba.
Eclipta alba belongs to the plant family Compositae. The inventor of the patent found that extracts obtained from the plant Eclipta alba possessed de-pigmenting properties, without provoking the side effects- a general whitening of the skin or else an excessive de-pigmentation of the regions treated. By fractionating the extracts obtained, the inventor additionally found that these properties were associated with the fraction of the plant which is rich in flavonoids, and that preparations containing wedelolactone or demethylwedelolactone, which are the main flavonoids of Eclipta alba, also possessed de-pigmenting properties.
Eclipta alba has been the subject of diverse studies, which have resulted in the discovery of various active principles. Conventional medicine has proposed various uses for Eclipta alba, in particular, in the West Indies, the crushed roots have been used as an anti-haemorrhagic agent, as well as in the treatment of leprosy. Some studies have led to an anti-viral activity being attributed to this plant, and more recently, some in vitro anti-bacterial activity. However, hitherto, no activity of Eclipta alba on skin pigmentation defects has been shown.
Acne, scientifically called Acne vulgaris is a common skin disorder in. It affects areas containing the largest oil glands, including the face, back, and trunk. It is generally characterised by formation of seborrhea, comedone, inflammatory lesions and presence of bacteria Propionibacterium acnes, Staphylococcus epidermidis and Malassezia furfur in the follicular canal and sebum production.
Researchers from the College of Pharmacy, A. Rangamepeta, Chittoor Dist, Andhra Pradesh, India, have examined 12 medicinal plants, which have been traditionally used as antimicrobial and anti-inflammatory agents for antimicrobial activities against microorganisms frequently involved in acne inflammation, Propionibacterium acnes and Staphylococcus epidermidis.
Ethanolic extracts of Hemidesmus indicus (roots), Eclipta alba (fruits), Coscinium fenestratum (stems), Curcubito pepo (seeds), Tephrosia purpurea (roots), Mentha piperita (leaves), Pongamia pinnata (seeds), Symplocos racemosa (barks), Euphorbia hirta (roots), Tinospora cordyfolia (roots), Thespesia populnea (roots), and Jasminum officinale (flowers) were tested for antimicrobial activities by disc diffusion and broth dilution methods.
The results from the disc diffusion method showed that seven of the 12 medicinal plants could inhibit the growth of Propionibacterium acnes. Among those Hemidesmus indicus, Coscinium fenestratum, Tephrosia purpurea, Euphorbia hirta, Symplocos racemosa, Curcubito pepo and Eclipta alba had strong inhibitory effects. Based on a broth dilution method, the Coscinium fenestratum extract had the greatest antimicrobial effect.
Phytochemical screening of Coscinium fenestratum revealed the presence of alkaloid, which could be responsible for activity. Taken together, our data indicated that Coscinium fenestratum had a strong inhibitory effect on Propionibacterium acnes and Staphylococcus epidermidis.
The study titled "Antimicrobial effects of Indian medicinal plants against acne-inducing bacteria" is published in Tropical Journal of Pharmaceutical Research.
According to the researchers, the similar values of the Minimal Inhibitory Concentration (MIC) and the Minimal Bactericidal Concentration (MBC) obtained from this plant against Propionibacterium acnes suggest that the ethanolic extract of Coscinium fenestratum could possibly act as a bactericidal agent to this microorganism.
Nigerian researchers have shown the anthelmintic (worm expeller) efficacy of the aqueous crude extract of Euphorbia hirta in Nigerian dogs.
Adedapo A. A., Shabi O. O., and Adedokun, O. A. of the Faculty of Veterinary Medicine, University of Ibadan, in a study published in Veterinarski Arhiv studied 20 Nigerian dogs that were naturally infected with nematodes.
The dogs were randomly divided into four groups, A, B, C and D. Groups A and B each comprised four dogs, while Groups C and D comprised six dogs each. Group A animals were left untreated, while those in Group B were treated with a proprietary anthelmintic (mebendazole). Groups C and D were treated with aqueous crude extracts of Euphorbia hirta using intramuscular and oral routes, respectively.
Two weeks after treatment, blood and faecal samples were collected to evaluate haematological values and faecal egg counts, respectively. The procedure was repeated two weeks later. It was shown that the aqueous crude extracts of Euphorbia hirta significantly increased haematocrit, erythrocyte count, haemoglobin concentration, total leukocyte count and lymphocyte counts.
The faecal egg counts also showed a remarkable and significant reduction in the levels of the identified helminths, which included Ancylostoma caninum, Toxocara canis, Dipylidium caninum and Echinococcus granulosus. The reduction in faecal egg counts was more pronounced with the extract administered through the oral route when compared with the intramuscular route.
The researchers concluded: "The effects of the plant extracts were broad spectrum in action. The phenol compound present in the plant extract could have caused the reduction in worm loads through this same mechanism that culminates in the exhaustion and death of the worms. Since the aqueous crude extract of Euphorbia hirta significantly reduced the faecal egg count of the helminths, it could serve as an anthelmintic agent."
In another study Euphorbia hirta leaf extracts were found to have antihypertensive action as they increased urine output and electrolytes in rats.
Johnson P. B. , Abdurahman E. M. , Tiam E. A., Abdu-Aguye I. and Hussaini I. M. of the Departments of Pharmacology and Clinical Pharmacya, Pharmacognosy, and Chemical Pathology of Ahmadu Bello University, Funtua Road, Zaria, Kaduna State verified local use of Euphorbia hirta in Africa and Australia to treat numerous diseases, including hypertension and edema.
The diuretic effect of E. hirta leaf extracts were assessed in rats using acetazolamide and furosemide as standard diuretic drugs. The water and ethanol extracts (50 and 100 mg/kg) of the plant produced time-dependent increase in urine output. Electrolyte excretion was also significantly affected by the plant extracts.
The water extract increased the urine excretion of sodium ion (Na+), potassium ion (K+) and hydrocarbonate ion (HCO3- ). In contrast, the ethanol extract increased the excretion of HCO3-, decreased the loss of K+ and had little effect on renal removal of Na+.
Acetazolamide, like the water extract, increased urine output and enhanced the excretion of Na+, K+ and HCO3-. The high-ceiling diuretic, furosemide, increased the renal excretion of Na+ and chlorine ion (Cl-), but had no effect on K+ and HCO3- loss.
The researchers wrote: "This study suggests that the active component(s) in the water extract of E. hirta leaf had similar diuretic spectrum to that of acetazolamide. These results validate the traditional use of E. hirta as a diuretic agent by the Swahilis and Sukumas."
A study, "Platelet Response to Methanolic and Aqueous Extracts Of Euphorbia hirta", published in the Nigerian Journal of Natural Products and Medicine, has validated the claim that Euphorbia hirta arrests bleeding and modulate haemostasis.
The extracts (aqueous and methanolic) were administered orally to albino wistar rats. Platelet count, bleeding and clotting times were determined before and at different time intervals after administration of the extracts. The aqueous extract at 60 minutes reduced bleeding time by 54 per cent compared to 49.5 per cent for methanolic extract and was significant.
Similarly, 84.1 per cent and 42.5 per cent reductions in clotting time were achieved with aqueous and methanolic extract respectively. Platelet count reductions with aqueous and methanolic extract were 19.2 per cent and 36.1 per cent. There was significant difference in clotting time of the two extracts after 30 min of administration. There was however, no significant correlation between the dose and activities of the extracts.
In another study published in the African Journal of Biotechnology, Nigerian researchers have examined the antibacterial activities and toxicological potentials of crude ethanolic extracts of Euphorbia hirta.
The results of the study by J. N. Ogbulie, C. C. Ogueke, I. C. Okoli, and B. N Anyanwu of the Departments of Industrial Microbiology, Food Science and Technology, Animal Science Technology of the Federal University of Technology, Owerri, Imo State, indicated that the ethanolic extract of the E. hirta inhibited the growth of the test isolates- Staphylococcus aureus, Escherichia coli,
Pseudomonas aeruginosa, and Bacillus subtilis, except Salmonella typhi.
This, therefore, shows that the extract contains substance(s) that can inhibit the growth of some microorganisms. Other workers have also shown that extracts of some plants inhibited the growth of various microorganisms at different concentrations.
The observed antibacterial effects on the isolates is believed to be due to the presence of alkaloids, tannins and flavonoids which have been shown to posses antibacterial properties.
Some workers have also attributed their observed antimicrobial effects of plant extracts to the presence of these secondary metabolites.
Some workers have also identified tannins, flavonoids and alkaloids in the extracts of some medicinal plant.
The observed antibacterial properties corroborate its use in traditional medicine. Traditionally, extracts of the plant are used in sore and wound healing, as ear drop for
boils in the ear and treatment of boils. They are also used in the control of diarrhoea and dysentery.
The large zones of inhibition exhibited by the extract against S. aureus and P. aeruginosa justified their use by traditional medical practitioners in the treatment of sores, bores and open wounds. S. aureus and P. aeruginosa have been implicated in cases of boils, sores and wounds. Also the moderate growth inhibition against E. coli justifies its use in the control of diarrhoea and dysentery. E. coli is the common cause of traveler's diarrhoea and other diarrhoeagenic infections in humans.
The low MIC exhibited by the extract against S. aureus is of great significance in the health care delivery system, since it could be used as an alternative to orthodox anti-biotics in the treatment of infections caused by these microbes, especially as they frequently develop resistance to known antibiotics. Their use also will reduce the cost of obtaining health care. The relatively high zone of inhibition exhibited by the extract against E. coli is also of significance, since E. coli is a common cause of diarrhea in developing countries.
The inability of the extract to inhibit Salmonella typhi may be that it possesses a mechanism for detoxifying the active principles in the extract. Some bacteria are known
to posses mechanisms by which they convert substances that inhibit their growth to non-toxic compounds. For examples S. aureus produces the enzyme penicillinase which converts the antibiotic penicillin to penicillinoic acid which is no longer inhibitory to its growth.
Statistical analysis revealed that for Red Blood Cells (RBC) there was no significant between the values obtained for the different concentrations of the extract injected and the control. This shows that the extract did not affect either the circulating red blood cells or the erythropoetic centres of the animals. Some workers have also shown that some extracts of plants do not have deliterious effects on RBC even up to 400 mg/kg body weight after 28 days of administration. This is also true for the White Blood Cells (WBC) counts. Thus, the extract did not induce production or destruction of the WBC. The same trend was also observed for the Hb content which indicates that the extract did not affect synthesis of hemoglobin by the animals. Some plants have been suggested to interfere with the synthesis of Hb by inhibition of the uptake and utilization of iron.
The researchers wrote: "These results indicate that the extract is less toxic heamatologically, at least to the rats, at the concentrations administered. E. hirta is commonly used traditionally in the treatment of wounds and boils as well as in the control of diarrhoea and dysentery in Nigeria. However, more work needs to be carried out to determine the chemistry of the particular active principle and the effect on the organs at these concentrations."
According to The Useful Plants of West Tropical Africa by H. M. Burkill, the Euphorbia hirta contains relatively abundant white latex, and in common with other lactiferous species, a decoction of the whole plant, or of the leaves, or the latex itself is used by women as a galactogogue (improve flow of breast milk). The plant has been an item of market trade in Northern Nigeria for this purpose. Preparations are massaged on to the breasts, or may be taken in draught.
Laboratory experiments on immature female guinea-pigs showed that the plant induced mammary development and secretion of milk. At Enugu Hospital, Ghana, the plant chewed with oil-palm kernels has been reported to act within 24 hours to produce a copious flow of milk. The plant has a diuretic and purgative action. It is widely used in treatment of venereal discharges. It is considered good for treating diarrhoea and dysentery.
Tests carried out in Conakry Hospital, Guinea, on patients with amoebic dysentery gave clear stool examinations and a cessation of bleeding after 48 hours treatment with a decoction of the fresh plant. Subsequent work has shown amoebicidal action of plant-extracts, which had practically no toxicity towards man or guinea-pig.
The plant is known as a remedy for inflammation of the respiratory tract, and for asthma it has a special reputation causing bronchial relaxation. Extract or decoction of the flowering or fruiting plant was entered in the British Pharmaceutical Codex for this but has long since been surpassed. The plant has also sometimes been combined with bronchial sedatives in preparations for inhalation.
Hausa medicine-men near Kano prescribe the leaf for chewing for coughs. The plant shows anti-biotic activity. A number of substances have been detected in the plant: tannins, gallic acid, quercetin, phenols, phyto-sterols, alcohols, alkaloid, without obvious active principles. The pharmacology requires further study. The plants used in East Africa as a treatment for Oxyuris threadworm and leaf-sap as a gargle for angina.
Sap is squeezed from the leaves into the eyes for styes and conjunctivitis, a practice that is known in E Africa and in Malaya as well as in Ivory Coast, Nigeria and Liberia. The latex is said to be capable of causing dermatitis. It is, however, thought to be cicatrisant and is applied to sores and wounds. It is used on ringworm in Indonesia. Tests have shown, some positive, some negative, anti-biotic action. Ghanaian children trace a pattern on the skin with the juice and rub in charcoal. The design can be removed by washing. The Ijaw of South Nigeria similarly create body-patterns which are said to be hard to wash off. They use the fruit for dyeing. The plant is used in Congo to relieve costal pains, and in decoctions with other plants to make a soothing wash for infants with fever. It has analgesic application for headache in Ivory Coast by nasal installation, and for rheumatism as a liniment and for pains in pregnancy in Nigeria.
Latex applied to a thorn or other foreign body will assist in extraction, and applied to a poison-arrow wound will act as an antidote to the poison and facilitate removal of the arrow-head. The use of the latex on warts, whitlows and the like is worldwide. The leaves are used by the Lobi and Kulango of Ivory Coast as an antidote to snake and scorpion poisons. The tender shoots are said to be edible and to serve in India as a famine-food. The plant is however considered to be slightly stimulant and narcotic. Goats are recorded browsing it in Kenya but it is shunned by cattle and camels. The plant is considered aphrodisiac in Tanzania (former Tanganyika), and a Fulani man of North Nigeria will take an infusion of the pounded leaves before going to a woman to ensure she will love him.
According to The Useful Plants of West Tropical Africa by H. M. Burkill, the leaves of Eclipta alba are mildly laxative and in large doses emetic. An extract is given for constipation in Ghana, and an infusion for diarrhoea in Nigeria. They are used in Ivory Coast for infantile diarrhoea after reduction to a paste in warm water and given as an enema. The plant's purgative and emetic properties especially in the roots are well-known in Asia.
The leaves are used in Ivory Coast to treat intestinal bleeding and for jaundice and convulsions in young children. The healing and cleansing property of the leaves is recognized in application of preparations to cuts and sores in Sierra Leone and in Ivory Coast and by the Tiv in Nigeria. In Tanganyika dried powdered leaves are sprinkled over injuries as a wound-dressing.
A burn-treatment in Gabon is to compound the leaves with djavŽ nut butter (Baillonella toxisperma, Sapotaceae) into an ointment, and a macerate of leaves with citron juice is applied to circumcision wounds and in embrocations for many different ailments. The sap from crushed leaves is taken for bronchial affections, and mixed with that of a pineapple and a pimento for massage over areas of oedema and kidney pains in Congo. With honey it makes a popular medicine for catarrh in infants.
The roots are used internally by the Wolof for liver complaints and sap from root and stem is taken in Nigeria for disorders of the liver and spleen and for dropsy. A root-decoction is used in Tanganyika for pains in the abdomen. The leaves contain a black dye furnishing an indelible stain, which explains the French name. For this either the sap can be used fresh or the leaves can be boiled and the liquor used. It has the capacity of blackening scar-tissue, so that when the leaves are used as a wound-dressing the scar heals a bluish-black. The sap is thus also used in tattooing, a practice known in Nigeria and in East Africa and India. It has been used in Asia from olden times as a hair-dye, and by extension put into preparations to promote hair-growth.
An extract of the whole plant has given promising action against the virus causing Raniket disease. Inconclusive results have been obtained for action on cancers. Positive antibiotic action against Staphylococcus aureus and Escherichia coli is reported. An unnamed alkaloid has been found present in the leaf and stem, and nicotine at 0.078 per cent dry weight. The eel-worm, Heterodera radicola, is reported to be very partial to attacking this plant which therefore offers the possibility of attracting and so removing this pest from cultivated plots. The plant may be ascribed with magical properties. In Gabon it is put into a special beverage for people 'possessed', and into a lotion with other plants to anoint a supplicant for special favours from influential persons.
