D.S. Grierson

Antibacterial activity of some indigenous plants used for the treatment of wounds in the Eastern Cape, South Africa

The use of medicinal plants in the world, and especially in South Africa, contributes significantly to primary health care. This paper presents the findings of an initial survey of plants used for the treatment of wounds in the Eastern Cape Province, South Africa. Ethnomedical information gathered from surveys at clinics, hospitals as well as interviews with traditional healers and rural dwellers has revealed that Grewia occidentalis, Polystichum pungens, Cheilanthes viridis and Malva parvifolia are the most commonly used plants for the treatment of wounds in the province. The methanol extracts of G. occidentalis, P. pungens and C. viridis showed significant inhibition against gram-positive and gram-negative bacteria, while the acetone extract of P. pungens inhibited the gram-positive bacteria only. Extracts from M. parvifolia did not show any antibacterial activity at 5.0 mg/ml. Generally, the antibacterial property of the plants appears to have justified their use for the treatment of wounds, which are contaminated through bacterial infection, in the province.

Antimicrobial Activity of Solanum aculeastrum.

Abstract Solanum aculeastrum. Dunal (Solanaceae) is used in traditional medicine to treat various human and animal diseases, specifically stomach disorders and various cancers, in the Eastern Cape, South Africa. The fruit and leaf extracts of this plant were investigated for in vitro. antimicrobial activity against 10 selected bacterial and 5 fungal strains. The methanolic extracts of both the fruits and the leaves showed appreciable activity against Gram-positive and Gram-negative bacteria ranging from 4.0 to 10.0 mg/ml. Whereas the methanol extracts were the most active material, the water extracts showed the least activity against the bacteria. The methanol extracts were particularly inhibitory to the growth of the fungi with percentage inhibition ranging from 60.26% to 100% and 56.0% to 100% on Aspergillus flavus. and Pencillium notatum., respectively. The acetone extracts were active against Aspergillus flavus. (100%) and Pencillium notatum. (64.81%), and the water extract of the fruit significantly inhibited the growth of P. notatum. (69.89%). The most resistant organisms were Aspergillus niger, Candida albicans., and Fusarium oxysporum..

An ethnobotanical study of plants used for the treatment of wounds in the Eastern Cape, South Africa.

The people of the Eastern Cape Province, South Africa, still depend, to a large extent, on traditional herbal medicine for the treatment of various diseases and ailments. This includes the use of plants for the treatment of wounds. Information collected from the traditional healers, the Sangomas, has revealed 38 plant species that are used for the treatment of wounds in the Province. The plants belong to 26 families of which Asteraceae, Asphodelaceae and Solanaceae are the most represented. The use of plant leaves as a poultice and infusions are the commonest categories of herbal preparations. In all cases, the treatment of wounds involved the external application of the herbal medicine.

Anticancer Activity of Steroid Alkaloids Isolated from Solanum aculeastrum.

Abstract Solanum aculeastrum. Dunal is a medicinal plant that has long been used to treat various cancers and many other conditions in the Eastern Cape Province of South Africa. In this study, two steroid glycosides were isolated from the berries of this plant, which were identified as tomatidine and solasodine by spectroscopic techniques. Effects on cell growth of these compounds were investigated with HeLa, MCF7, and HT29 cancer cell lines. The IC50 values confirmed that tomatidine and solasodine had the highest inhibitory effect on HeLa cells and the IC50 of the combined compounds was lower than the value for solasodine and unchanged from that of tomatidine. However, the IC50 values of the two compounds combined was also lower in HT29 and MCF7 cells than for the individual compounds. Both tomatidine and solasodine inhibited cell growth by blocking the cell cycle in the G0/G1 phase after 24-h exposure with an increase from 55.6% to 64.2% and 66.8%, respectively. Using annexin V–FITC/PI staining by flow cytometry, the compounds showed very low apoptotic indices.

Ethnobotanical survey of medicinal plants used in the management of skin disorders among the Xhosa communities of the Amathole District, Eastern Cape, South Africa

ETHNOPHARMACOLOGICAL RELEVANCE Skin diseases have been of major concern recently due to the association of skin opportunistic infections and HIV/AIDS, are usually the first sign of HIV infection and conversion to AIDS. More than 90% of HIV-infected individuals develop skin and mucosal complications at some stage during the disease. Although classical medicine is undoubtedly addressing these diseases, the people of the Eastern Cape, South Africa still depend, to a large extent on traditional herbal medicine for the treatment of various diseases. The current study was undertaken to investigate the local peoples characterisation of skin diseases/disorders and to document the medicinal plants used for various skin disorders among the Xhosa-speaking communities of the Amathole District, Eastern Cape. MATERIALS AND METHODS Information was obtained by interviewing 54 respondents in 7 locations. Collection of the reported medicinal plants from the wild was assisted by the informants and identification of the collected plants specimens was done with the help of floristic works of South Africa. Quantitative methods including the use-value and the informant consensus factor (ICF) were computed for determining the relative importance of species known locally and the homogeneity of the informants׳ knowledge respectively. RESULTS Twenty five skin disorders, classified under 5 categories are being treated with the listed medicinal plants in the study area. The highest ICF (0.45) was linked to bacteria-related skin disorders. This category comprised of 57 use citations, 3 skin disorders; with sore throat being the most frequently mentioned (4.2%). In this study, 106 plant species distributed in 61 families and 107 genera were identified as being used to treat one or more of the skin disorders. The species with the highest use-value was Aloe ferox Mill. (Xanthorrhoeaceae) known locally as Umhlaba. The most representative families were Solanaceae and Asteraceae with 6 species each, followed by Fabaceae, Poaceae and Rutaceae (5 species each). The leaves were the most frequently used plant part, followed by the bark (10%) and fruits (7%). Administration of the different plant parts was mostly topical (77%) on the affected area. CONCLUSION A total of twenty five skin disorders/conditions, classified under 5 categories are being treated with the listed medicinal plants in the study area. 106 plant species distributed in 61 families and 107 genera were identified as being used to treat one or more of the skin disorders. The species with the highest use-value was Aloe ferox Mill. (Xanthorrhoeaceae) known locally as Umhlaba. The most representative families were Solanaceae, Asteraceae, Fabaceae, Poaceae, Rutaceae and Euphorbiaceae. Majority of the plant species were herbs and the leaves were the most frequently used, mostly applied topically as a paste, powder or sap on the affected skin area.

Phytochemical studies and antioxidant activity of two South African medicinal plants traditionally used for the management of opportunistic fungal infections in HIV/AIDS patients

BackgroundIt has been observed that perturbations in the antioxidant defense systems, and consequently redox imbalance, are present in many tissues of HIV-infected patients. Hence, the exogenous supply of antioxidants, as natural compounds that scavenge free radicals, might represent an important additional strategy for the treatment of HIV infection. The aim of this study was therefore to analyse the phytochemical constituents and antioxidant potential of Gasteria bicolor Haw and Pittosporum viridiflorum Sims., two South African plants traditionally used for the management of opportunistic fungal infections (OFIs) in AIDS patients.MethodsThe in vitro antioxidant properties of the two plants were screened through DPPH (1,1-diphenyl-2-picrylhydrazyl), NO (nitric oxide), H2O2 (hydrogen peroxide) radical scavenging effects and reducing power assays. Phytochemical studies were done by spectrophotometric techniques.ResultsThere were no significant differences in the flavonoid and proanthocyanidins contents between the leaves and bark extracts of Gasteria bicolor and Pittosporum viridiflorum respectively, while the total phenolic content of the bark extract of P. viridiflorum was significantly higher than that of G. bicolor leaf. The acetone extracts of both plants indicated strong antioxidant activities.ConclusionThe results from this study indicate that the leaves and stem extracts of Gasteria bicolor and Pittosporum viridiflorum respectively possess antioxidant properties and could serve as free radical inhibitors, acting possibly as primary antioxidants. Since reactive oxygen species are thought to be associated with the pathogenesis of AIDS, and HIV-infected individuals often have impaired antioxidant defenses, the inhibitory effect of the extracts on free radicals may partially justify the traditional use of these plants in the management of OFIs in HIV patients in South Africa.

Antifungal activity of Arctotis arctotoides (L.f.) O. Hoffm. and Gasteria bicolor Haw. against opportunistic fungi associated with human immunodeficiency virus/acquired immunodeficiency syndrome.

Background: In South Africa where many patients are immunocompromised as a result of the AIDS pandemic, opportunistic fungal infections such as candidiasis caused mainly by Candida albicans are common. Arctotis arctotoides and Gasteria bicolor are two plants which are frequently and commonly used in traditional medicine in the treatment of HIV patients. Aim: The aim of this study was to investigate the antifungal activity of A. arctotoides and G. bicolor against opportunistic fungi common in HIV/AIDS patients. Materials and Methods: The agar diffusion and micro-dilution methods were used to determine the antifungal activities of the medicinal plant extracts against 10 opportunistic fungi. Results: All the hexane and acetone extracts were active against at least one of the fungi with zones of inhibition varying from 8 to 32 mm, while none of the aqueous extracts was active against any of the fungi. The inhibitory activity of the active extracts, based on the overall mean inhibition diameters, was in the order: A. arctotoides (hexane) > A. arctotoides (acetone) > G. bicolor (hexane) > G. bicolor (acetone). The most susceptible fungi, based on the overall mean diameter of growth inhibition, were Candida glabrata, C. krusei, and Microsporum canis, while Cyptococcus neoformans, Trycophyton tonsurans, and Microsporum gypseum were not susceptible to any of the extracts even at 5 mg/ml which was the highest concentration used. Conclusion: This study validates the use of these plants in traditional medicine in the treatment of secondary fungal infections in HIV/AIDS patients.

Studies on the toxicological effect of the aqueous extract of the fresh, dried and boiled berries of Solanum aculeastrum Dunal in male Wistar rats.

The toxicological effect of the aqueous extract of fresh, dried and boiled berries of Solanum aculeastrum Dunal at 1, 10 and 25 mg/kg body weight was investigated in male Wistar rats for 28 days. The parameters used were the body weight of the animals and absolute weights of the organs, haematological parameters, renal and liver functional endpoints. The animals gained appreciable weight and showed no signs of clinical toxicity. The dried (DB), boiled dried (BDB), fresh (FB) and boiled fresh berry (BFB) extracts reduced (p < .05) the heart-, liver-and spleen-body weight ratio of the animals whereas that of the lung was not altered. The kidney and testes-body weight ratios were specifically altered by the different extract. All these were not accompanied by any histomorphological changes. The extracts did not alter (p > .05) the levels of RBC, Hb, PCV and albumin of the animals. The platelets were decreased by the DB and FB whereas BFB increased this parameter. The FB and BFB at all the doses also reduced the mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) of the animals. With the exception of the FB where the creatinine and chloride levels decreased, other extracts did not alter the level of these kidney parameters. Only FB increased the levels of uric acid and urea. All the extract decreased the serum alanine aminotransferase (ALT) of the animal. The levels of total protein, globulin, total and conjugated bilirubin were not altered by DB and BDB whereas these indices were increased by FB and BFB. The DB and BDB increased the serum alkaline phosphatase (ALP) activity whereas FB decreased the activity of the enzyme. In contrast, DB and BDB decreased the serum aspartate aminotransferase (AST) activity of the animals whereas FB and BFB increased the activity of the enzyme. The FB and BFB also increased the levels of potassium, magnesium and phosphorus of the animals. Overall, the alterations in the biochemical parameters by the various extracts of S. aculeastrum berries at these doses indicated that the normal functioning of these organs may be adversely affected. However, drying and boiling might reduce the toxic effect of the berries.

Extracts from Pelargonium sidoides inhibit the growth of bacteria and fungi

Abstract Pelargonium sidoides. DC (Geraniaceae) is a medicinal plant used by the people of the Eastern Cape, South Africa, for the treatment of various diseases in man and livestock. Acetone and methanol extracts of the shoot and root of the herb were investigated for antimicrobial activity against 10 bacterial and 5 fungal species by the dilution method on solid agar medium. With the exception of Staphylococcus epidermidis., extracts obtained from both solvents demonstrated significant activity against all the Gram-positive and two of the Gram-negative bacteria tested in this study. The extracts also showed appreciable inhibitory activity against all the fungal species tested with inhibition ranging from 52.5% on Aspergillus flavus. to 82.5% on Mucor hiemalis. at 5 mg ml−1, the highest concentration tested in the study. The ability of the extracts of this plant to inhibit the growth of several bacteria and fungi is an indication of the broad-spectrum antimicrobial potential of P. sidoides. that further validates the use of this plant for the treatment of various ailments by the people of the Eastern Cape.

Morphological diversity among accessions of Pelargonium sidoides DC. in the Eastern Cape, South Africa

Pelargonium sidoides is an indigenous medicinal plant of South Africa harvested for local use and international trade. Due to its high economic and medicinal importance, the rate and the number of its harvesters have increased in recent years. This has led to a drastic drop in the population of the species in the wild. In order to develop breeding and propagation program for this species, a baseline study was conducted to determine the morphological variability exhibited by 30 accessions of P. sidoides collected from three locations within the Eastern Cape. A list of descriptors developed by IPGRI/IITA/BAMNET for Bambara groundnut was adopted and a total of 16 traits (2 qualitative and 14 quantitative) were determined during the vegetative and reproductive stages. Data were subjected to univariate and multivariate statistical analyses. Ample variability was found for most traits measured. Cluster analysis showed unique clustering of accessions forming 29 morphotypes (clusters) out of the 30 accessions studied. At the core level, plant materials collected from the same location were found to cluster in pair of accessions thus implying similarity of adaptation. The reproductive characters which include number of flowers per inflorescence, length and width of inflorescence and number of inflorescence per vine showed the highest variation among the quantitative characters measured. The importance of this work on the propagation and conservation of Pelargonium sidoides is discussed.