Antimicrobial evaluation of plants used for the treatment of diarrhoea in a rural community in northern Maputaland, KwaZulu-Natal, South Africa

Abstract

BackgroundZulu people living in the rural area of Maputaland (KwaZulu-Natal, South Africa) rely heavily on medicinal plants for the treatment of diarrhoea. Abundant availability of medicinal plants in the study area offers low cost health care, but scientific validation is needed in order to lend credibility to the traditional use against many ailments including diarrhoeal infections. With this in mind a study was designed to test the in vitro antimicrobial efficacy of 23 plant species which are used for the treatment of diarrhoea in rural Maputaland. Four 1:1 plant combinations were also evaluated to determine their interactive effects against seven diarrhoea-related bacterial pathogens.MethodsMinimum inhibitory concentration (MIC) assays were undertaken on dichloromethane-methanol (CH2Cl2: MeOH) and aqueous crude extracts. The following micro-organisms were selected for this study and were tested based on their association with stomach ailments and diarrhoea; Bacillus cereus (ATCC 11778), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 8739), Proteus vulgaris (ATCC 33420), Salmonella typhimurium (ATCC 14028), Shigella flexneri (ATCC 25875) and Staphylococcus aureus (ATCC 12600). The fractional inhibitory concentration index (ΣFIC) was determined for plants traditionally used in combination.ResultsShigella flexneri proved to be the most susceptible pathogen, where the organic extract of Terminalia sericea showed the most prominent noteworthy antibacterial activity (mean MIC value of 0.04 mg/mL). The aqueous extracts generally showed poorer antimicrobial activity with some exceptions i.e. Acacia burkei, Brachylaena transvaalensis against B. cereus and B. transvaalensis against S. flexneri. In the combination studies, synergy was predominant with mean (across all pathogens) ΣFIC values of 0.30 for Acanthospermum glabratum with Krauseola mosambicina; ΣFIC values of 0.46 for A. glabratum with Psidium guajava; ΣFIC values of 0.39 for B. transvaalensis with P. guajava and ΣFIC values of 0.88 (additive) for the combination of B. transvaalensis with Sclerocarya birrea.ConclusionThis study provided some insight into the bacterial in vitro efficacies of plants traditionally used to treat diarrhoea by the people of Northern Maputaland. Very little connection was observed between frequency of use and efficacy. Plant combinations demonstrated favourable efficacy with mostly synergistic effects noted, lending some credibility to their use in combination.

Antibacterial activity of Cordia dentata Poir, Heliotropium indicum Linn and Momordica charantia Linn from the Northern Colombian Coast

“…Antibacterial activity was determined by modified agar gel diffusion method [27]. Autoclaved Mueller-Hinton agar (MHA) was poured into sterile Petri dishes and solidified into plate.…”

Treatment of Diarrhoea Using Traditional Medicines: Contemporary Research in South Africa and Zimbabwe

“…A better understanding of these processes supported by ethnopharmacological uses is important for effective diarrhoea management and control in South Africa and Zimbabwe. Previous researchers such as Dambisya and Tindimwebwa (2003) and van Vuuren et al (2015) are of the opinion that there is correlation between socio-demographic factors and the use of antidiarrhoeal medicinal plants in South Africa. Therefore, some of the plant species documented in this study will play an important role as main sources of primary healthcare available and accessible to all the people in South Africa and Zimbabwe, particularly the poor.…”

“…Previous research in the Eastern Cape province of South Africa where an estimated 72% of the population lives below the poverty line (Thornton, 2009), revealed that diarrhoea is one of the major diseases treated and managed by traditional medicines (Dambisya & Tindimwebwa, 2003). Northern Maputaland in KwaZulu-Natal province is another province characterized by high poverty levels in South Africa where diarrhoea is a major concern and herbal medicines are widely used to manage and treat diarrhoea (van Vuuren et al, 2015). Similarly, gastrointestinal diseases such as cholera, diarrhoea and dysentery are among the most prominent diseases in Zimbabwe resulting in high mortality rate if not treated promptly (Maroyi, 2013).…”

Plants used to treat skin diseases in northern Maputaland, South Africa: antimicrobial activity andin vitropermeability studies

“…Hutchings et al (1996) documented S. brachypetala as a treatment of acne; however, to the best of our knowledge, no other studies have investigated this plant against the acne-associated pathogen P. acnes. Previous studies on S. brachypetala have focused on diarrhoeal pathogens (Mathabe et al 2006;van Vuuren et al 2015). With the exception of S. aureus, no other studies were found that investigated the effectiveness of S. brachypetala against skin pathogens.…”

“…(Asteraceae) and S. birrea were the most frequently mentioned treatments for skin ailments by the lay people of northern Maputaland. The antimicrobial properties of S. birrea have been studied previously and the bark extracts have been found to possess antimicrobial activity against various pathogens (McGaw et al 2000;Eloff 2001;York et al 2012;Naidoo et al 2013;van Vuuren et al 2015). This plant was reported to treat burns, boils and sores independently as well as used in combination with other plants (De Wet et al 2013).…”