Antimicrobial activity of tanzanian chewing sticks against oral pathogenic microbes

Effect of methanol root extract of Eriosema psoraleoides on biochemical and haematological parameters and cyclooxygenase levels in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Eriosema psoraleoides is a remedial plant utilised traditionally in the African continent. It is said to possess a wide range of pharmacological activity. In a previous study, the analgesic and anti-inflammatory activity of its methanol root extract have been scientifically demonstrated. The growing use of medicinal plants by people from low-income countries and the plethora of adverse effects accompanying this increasing use has demonstrated the need for comprehensive toxicological evaluation of these plants which have shown therapeutic activity. However, in the capsule that is Nigeria, these studies are seldom done even though locals continue to patronize these plants for their health benefits.

AIM OF THE STUDY

To establish the repeated dose toxicity profile of the methanol root extract of Eriosema psoraleoides (EPE) in rats and also to investigate a possible mechanism for its analgesic and anti-inflammatory activity.

MATERIALS AND METHODS

Male Wistar rats were utilised for the test. All animals used for the test were healthy. The oral repeated dose study was carried out for 28 days with animals being given the following doses daily; 250, 500 and 1000 mg/kg orally. The Wistar rats were euthanized afterwards and blood samples were taken. The samples were subjected to serum biochemistry in tandem with haematological testing. After acute induction of inflammation with 1% carrageenan in normal saline, sera samples were obtained from the animals: serum cyclooxygenase 1 and 2 levels (COX 1 and COX 2) were assayed using Enzyme-Linked Immunosorbent Assay kits. Data were analysed utilising the appropriate software and tests.

RESULTS

Oral Repeated dose administration of EPE for 28 days didn't produce any lethality in any animal throughout the duration of the test. Repeated dose administration of EPE showed a significant (p < 0.05) decrease in the serum levels of Alanine Aminotransferase as well as Aspartate Aminotransferase at 250 and 1000 mg/kg dose levels. Total protein and albumin were also significantly (p < 0.01) decreased. A statistically significant (p < 0.05) decrease in serum urea level was also observed compared to the normal saline group (1 ml/kg). Sodium levels also showed a decrease with a statistically significant level only in the group treated with the extract at a dose of 1000 mg/kg (p < 0.05). Haematological parameters were not significantly affected by EPE. The extract demonstrated an ability to down-regulate serum concentration of both COX 1 and 2, though not to a statistically significant level.

CONCLUSION

The results of this study suggest that prolonged use of EPE might potentially adversely affect vital organs in the body and EPE may potentially act through its downregulation of COX 1 and 2.

Evaluation of the Antidiarrheal and Antioxidant Effects of Some Chewing Sticks Commonly Used for Oral Hygiene in Ghana

Microbial etiology of diarrhea is a significant cause of death, especially in children in developing countries. The presence of microbes that are resistant to current treatment options for diarrhea suggests the need to find newer antimicrobial agents for treatment. Therefore, this study focused on investigating the antimicrobial effect of some Ghanaian chewing sticks commonly used for oral hygiene, Azadirachta indica, Garcinia afzelii, and Garcinia kola, against selected diarrhea-causing organisms. From the stem and bark of each plant, 70% methanolic extract was experimented on Salmonella and Shigella species, namely, Shigella sonnei, Shigella flexeneri, Salmonella typhinirium enterica, Salmonella typhi attenuated, and Klebsiella oxytoca for microbial susceptibility using the agar well diffusion method. Additionally, the antioxidant profile of the methanolic extracts were investigated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic) acid (ABTS) scavenging activities, and ferric-reducing antioxidant potential (FRAP) assays, while the total polyphenolic content was determined using the Folin–Ciocalteau reagent. G. afzelii and A. indica stem demonstrated the highest antimicrobial effect, inhibiting the growth of all test organisms. Additionally, the extracts demonstrated high antioxidant potential and were found to possess significant amounts of phenolic compounds. Therefore, methanolic extracts of G. afzelii and A. indica stem are promising candidates for the identification of safe novel compounds to mitigate diarrheal diseases.

The Genus Eriosema (Fabaceae): From the Ethnopharmacology to an Evidence-Based Phytotherapeutic Perspective?

The genus Eriosema (Fabaceae) includes approximately 150 species widely distributed across tropical and subtropical regions of the world (Africa, Neotropics, Asia and Australia). Throughout these regions, several species are used since centuries in different traditional medicinal systems, while others are used as food or food supplement. The present review attempts to critically summarize current information concerning the uses, phytochemistry and pharmacology of the Eriosema genus and to evaluate the therapeutic potential. The information published in English and French (up to September 2020) on ethnopharmacology or traditional uses, chemistry, pharmacology and toxicology of Eriosema genus was collected from electronic databases [SciFinder, PubMed, Google, Google Scholar, Scopus, Web of Science, Prelude Medicinal Plants—http://www.ethnopharmacologia.org/recherche-dans-prelude/?plant, The Plant List (http://www.theplantlist.org/), POWO (http://powo.science.kew.org/) and IUCN Red List Categories (https://www.iucnredlist.org/)], conference proceedings, books, M.Sc. and Ph.D. dissertations. The information retrieved on the ethnomedicinal indications of Eriosema genus allowed to list 25 species (∼16.6% of the genus). The majority of uses is recorded from Africa. Phytochemical analyses of 8 species led to the identification and/or isolation of 107 compounds, with flavonoids (69.2%), chromones (7.5%) and benzoic acid derivatives (3.7%) as the main chemical classes. Pharmacological investigations with crude extracts and isolated compounds showed a broad range of activities including aphrodisiac, estrogenic, anti-osteoporosis, hypolipidemic, anti-diabetic, anti-diarrheal, anti-microbial, anti-oxidant, anthelmintic, anti-cancer, and acetylcholinesterase inhibitory activities. Despite the low number of Eriosema species tested, there is convincing evidence in vitro and in vivo studies validating some traditional and ethnobotanical uses. However, the utility of several of the described uses has not yet been confirmed in pharmacological studies. Reviewed data could serve as a reference tool and preliminary information for advanced research on Eriosema species.

Extraction of Flavonoids from Corn Silk and Biological Activities In Vitro

When harvesting corn, corn silk was discarded as waste, including the compounds isolated and identified from corn silk such as flavonoids, sterols, alkaloids, polysaccharides, organic acids, volatile oils, trace elements, and multivitamins. It not only pollutes the environment but also wastes resources. In this paper, extraction methods commonly used for extracting flavonoids from corn silk were reviewed, such as reagent method, enzymatic method, microwave, supercritical CO2 extraction, ultrasonic, and microwave-assisted ultrasonic. Flavonoids are natural antioxidants and have application value in scavenging free radicals, inhibiting bacteria, and regulating blood lipids. The in vitro biological activities of flavonoids from corn silk extracted by different extraction methods were also compared.

Testing the Antimicrobial Characteristics of Wood Materials: A Review of Methods

Some wood species have antimicrobial properties, making them a better choice over inert surfaces in certain circumstances. However, the organic and porous nature of wood raises questions regarding the use of this material in hygienically important places. Therefore, it is reasonable to investigate the microbial survival and the antimicrobial potential of wood via a variety of methods. Based on the available literature, this review classifies previously used methods into two broad categories: one category tests wood material by direct bacterial contact, and the other tests the action of molecules previously extracted from wood on bacteria and fungi. This article discusses the suitability of these methods to wood materials and exposes knowledge gaps that can be used to guide future research. This information is intended to help the researchers and field experts to select suitable methods for testing the hygienic safety and antimicrobial properties of wood materials.

Oral health in transition: The Hadza foragers of Tanzania

Conventional wisdom holds that a decline in oral health accompanies the transition from hunting and gathering to agriculture, given increased consumption of carbohydrates. This widely touted example of the mismatch between our biology and modern lifestyle has been intuited largely from the bioarchaeological record of the Neolithic Revolution in the New World. Recent studies of other populations have, however, challenged the universality of this assertion. Here, we present the first comprehensive study of oral health among a living population in transition from the bush to village life, the Hadza hunter-gatherers of Tanzania, to test the hypothesis that the shift from foraging to farming, or agricultural intensification, inevitably leads to increased periodontal disease, caries, and orthodontic disorders. Our results showed that women living in villages consuming a mostly agricultural diet exhibited more caries and periodontal disease than those living in the bush consuming a mostly wild-food diet. Furthermore, men living in the bush consuming mostly a wild-food diet had more than those living in the village consuming a mostly agricultural diet. These findings are explained by the high incidence of maize consumption in village settings, along with previously recognized variation in rate of caries between men and women. The unexpected discovery of high caries incidences for men in the bush is likely explained by heavy reliance on honey, and perhaps differential access to tobacco and marijuana. These data support the notions that mechanisms of cariogenesis are multifactorial and that the relationships between oral health and the shift from a predominantly wild-food diet to one dominated by cultigens are nuanced.

Growth inhibition and apoptosis of Ehrlich ascites carcinoma cells by the methanol extract of Eucalyptus camaldulensis

CONTEXT

Eucalyptus camaldulensis Dehnh. (Myrtaceae) is a tall evergreen tree found commonly in Bangladesh. Its use in traditional folk medicine for the treatment of various health complications are well known.

OBJECTIVE

To explore the in vivo antitumor effect of Eucalyptus camaldulensis stem bark methanol extract (ME) against Ehrlich's ascites carcinoma (EAC) in Swiss albino mice.

MATERIALS AND METHODS

The antitumor activity of ME was studied by determining viable tumor cell count, recording tumor weight and survival time, observing morphological changes and nuclear damage of EAC cells, and estimating hematological as well as biochemical parameters of experimental mice (25, 50 and 100 mg/kg/day for 5 d, i.p.).

RESULTS

ME showed 96% (p < 0.001) cell growth inhibition and reduced tumor burden significantly (81.4%; p < 0.01) when compared with control mice. It also increased the lifespan of EAC-bearing mice significantly (71.36%; p < 0.01). It also restored the altered hematological and biochemical parameters towards normal level. The high LD50 value (1120 mg/kg) of ME indicated its low host toxic effects. ME-treated EAC cells showed membrane blebbing, chromatin condensation, nuclear fragmentation (apoptotic features) in Hoechst 33342 staining under fluorescence microscope. The DNA profile in agarose gel (1.5%) electrophoresis also confirmed that ME caused EAC cell death by apoptosis.

DISCUSSION AND CONCLUSION

Results showed that ME exhibits strong anticancer activity through apoptosis and stimulation of host immunity. Thus, E. camaldulensis may be considered as a promising resource in cancer chemotherapy.

Bioactivities of the genus Combretum (Combretaceae): a review

The Combretaceae is a large family of herbs, shrubs and trees, comprising about 20 genera and 600 species with tropical distribution around the globe and centers of diversity in Africa and Asia. Some Combretum species are extensively used in traditional medicine against inflammation, infections, diabetes, malaria, bleeding, diarrhea and digestive disorders and others as a diuretic. The present work is a literature survey of Combretum species that have been evaluated for their ability to exert biological activities. A total number of 36 Combretum species are discussed with regard to plant parts used, component tested and bioassay models. This review is of fundamental importance to promoting studies on Combretum species, thereby contributing to the development of new therapeutic alternatives that may improve the health of people suffering from various health problems.

Traditional antimalarial phytotherapy remedies used by the South Coast community, Kenya

AIM OF THE STUDY

This study was conducted to document herbal medicines used in the treatment of malaria as well as the existing knowledge, attitudes and practices related to malaria recognition, control and treatment in South Coast, Kenya.

METHODS

Data was collected using semistructured questionnaires and interviews. A focused group discussion held with the community members, one in each of the study villages supplemented the interview and questionnaire survey.

RESULTS

The respondents were found to have a good understanding of malaria and could distinguish it from other fever types. They were also aware that malaria was spread by mosquitoes. Malaria prevalence was high, and affected individuals an average of four times a year. Community members avoided mosquito bites by using mosquito nets, clearing bushes around their homesteads and burning plant parts to generate smoke. They prevented and treated malaria by taking decoctions or concoctions of traditional herbal remedies. Forty plant species in thirty-five genera distributed in twenty-four families were used as antimalarials in the study area. Five plant species, namely; Heeria insignis Del. (Anacardiaceae), Rottboelia exaltata L.F (Gramineae), Pentanisia ouranogyne S. Moore (Rubiaceae), Agathisanthenum globosum (A. Rich) Hiern (Rubiaceae), and Grewia trichocarpa Hochst ex A. Rich (Tiliaceae) are documented for the first time in South Coast, Kenya, for the treatment of malaria.

CONCLUSIONS

The plants documented in the current study are a potential source for new bioactive compounds of therapeutic value in malaria treatment. The results provide data for further pharmacological and toxicological studies and development of commercial antimalarial phytotherapy products.

Antimalarial herbal remedies of Msambweni, Kenya

Malaria is a serious cause of mortality globally. The disease is of regional concern in Africa and of national interest in Kenya due to its high morbidity and mortality as a result of development of resistant strains of Plasmodium falciparum to many existing drugs such as chloroquine. Alternative medicine using herbal remedies are commonly used to treat malaria in Kenya. However, plants used in some rural areas in Kenya are not documented. Many antimalarial drugs have been derived from plants. This study was conducted to document medicinal plants that are traditionally used by the Msambweni community of Kenyan South Coast to treat malaria, where the disease is endemic. Herbalists were interviewed by administration of semistructured questionnaires in order to obtain information on medicinal plants traditionally used for the treatment of malaria. Focused group discussions held with the herbalists supplemented the interview and questionnaire survey. Twenty-seven species of plants in 24 genera distributed in 20 families were reported to be used in this region for the treatment of malaria. Labiatae, Rutaceae and Liliaceae families had each eleven percent of the plant species reported and represented the species that are most commonly used. Thirteen plant species, namely; Aloe deserti Berger (Liliaceae), Launea cornuta (Oliv and Hiern) C. Jeffrey (Compositae), Ocimum bacilicum L. (Labiatae), Teclea simplicifolia (Eng) Verdoon (Rutaceae), Gerranthus lobatus (Cogn.) Jeffrey (Cucurbitaceae), Grewia hexaminta Burret. (Tiliaceae), Canthium glaucum Hiern. (Rubiaceae), Amaranthus hybridus L. (Amaranthaceae), Combretum padoides Engl and Diels. (Combretaceae), Senecio syringitolius O. Hoffman. (Compositae), Ocimum suave Willd (Labiatae), Aloe macrosiphon Bak. (Liliaceae) and Laudolphia buchananii (Hall.f) Stapf. (Apocynaceae) are documented from this region for the first time for the treatment of malaria. These results become a basis for selection of plants for further pharmacological, toxicological and phytochemical studies in developing new plant based antimalarial drugs.

Antifungal activity of some Tanzanian plants used traditionally for the treatment of fungal infections

Using the ethnobotanical approach, some Tanzanian plants reported to be used by traditional healers for the treatment of oral candidiasis and fungal infections of the skin were collected and screened for their antifungal activity against Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, Candida krusei and Cryptococcus neoformans. A total of 65 crude methanol extracts belonging to 56 plant species and 38 families were screened using the broth microdilution method, according to the guidelines of the Clinical and Laboratory Standard Institute (CLSI) (formerly, National Committee for Clinical and Laboratory Standards) [National Committee for Clinical Laboratory Standards, 2002. Reference Method for Broth Dilution Antifungal Susceptibility Testing of Yeasts. Approved Standard-2nd Edition M27-A2, National Committee for Clinical Laboratory Standards, Wayne, PA, USA]. Among the tested plant species, 45% (25 species) showed antifungal activity against one or more of the test fungi. The most susceptible yeasts were Cryptococcus neoformans, followed by Candida krusei, Candida tropicalis, and Candida parapsilosis. The least susceptible were Candida albicans and Candida glabrata. Strong antifungal activity was exhibited by extracts of Clausena anisata Oliv., Sclerocariya birrea Sond, Turraea holstii Gurk, Sterculia africana (Lour) Fiori, Acacia robusta subsp. Usambarensis (Taub) Brenan, Cyphosterma hildebrandti (Gilg), Desc, Elaeodendron buchannanii (Lows), Acacia nilotica (L.) Wild ex Del, Jatropha multifida L., and Pteridium aquilinum (L.) Kuhn.

Medicinal plants used by Tanzanian traditional healers in the management of Candida infections

An ethnomedical survey in Coast, Dar es Salaam, Morogoro and Tanga regions of Tanzania has resulted in the identification of 36 plant species belonging to 21 plant families that are used traditionally for the treatment of Candida infections. Twenty-one plants constituting 58.3% of all collected plants are used to treat of oral candidiasis (Utando) one of the important signs of HIV/AIDS. The knowledge of traditional healers for the treatment of Candida infections has been highly supported by the literature in that 13 (36.1%) out of the 36 plants identified have been proven to be active against Candida albicans and/or other species of Candida. Also, some of the plants were reported to be active against other species of fungi including Cryptococcus neoformans, one of the important pathogenic fungi in HIV/AIDS. It can be seen that ethnomedical information from traditional healers provides a solid lead towards development of new drugs than random screening. The task that remains is to screen extracts prepared from these plants and perform a bioassay-guided fractionation of the active extracts so as to isolate the active compounds from these plants.

Screening of Tanzanian medicinal plants for anti-Candida activity

Background

Candida albicans has become resistant to the already limited, toxic and expensive anti-Candida agents available in the market. These factors necessitate the search for new anti-fungal agents.

Methods

Sixty-three plant extracts, from 56 Tanzanian plant species obtained through the literature and interviews with traditional healers, were evaluated for anti-Candida activity. Aqueous methanolic extracts were screened for anti-Candida activity by bioautography agar overlay method, using a standard strain of Candida albicans (ATCC 90028).

Results

Twenty- seven (48%) out of the 56 plants were found to be active. Extracts of the root barks of Albizia anthelmintica and Balanites aegyptiaca, and roots of Plectranthus barbatus showed strong activity.

Conclusion

The extracts that showed strong anti-Candida activity are worth of further investigation in order to isolate and identify the active compounds.

Tooth loss among habitual chewing-stick and plastic toothbrush users in the adult population of Mtwara, rural Tanzania1

OBJECTIVES

The aim of this study was to determine the extent and type of tooth loss in relation to habitual chewing-stick (CS) and plastic toothbrush (PT) users in adults.

METHODS

A cross-sectional descriptive study was conducted in Mtwara's rural population aged >or=40 years. A total of 206 randomly selected study participants - males (55.8%) and females (44.2%) - were interviewed on oral hygiene practices using a structured questionnaire, and a clinical examination performed for assessment of tooth loss.

RESULTS

Of the total, 93.2% were partially edentulous, 2.4% completely edentulous and those with no tooth loss 4.4%. The total number of missing teeth were 1728 (mean, 8.38 +/- 7.9), and the causes were caries (74.9%), mutilation (4.8%) and others including periodontal and trauma (20.3%). There was no significant difference in the mean number of tooth loss between the upper and lower jaw, and between males and females. However, the mean number of missing teeth in the lower jaw was higher in females than in males (P = 0.04), and on lower left than lower right jaw (P = 0.008). Lower molars, especially first molars, were the teeth lost most often. Tooth-cleaning devices included PT (51.5%), CS (25.7%), both type (BT; 17.0%) and unspecified (5.8%). The differences in the mean number of missing teeth were higher in CS than habitual PT users (P = 0.024) and in BT (P = 0.029). Tooth loss was also higher among those who brushed once when compared with those who brushed two times or more per day (P = 0.046).

CONCLUSION

Tooth loss was significantly higher in CS than PT habitual users and affected mostly the lower molars and especially the first molar. However, for economical reasons, effective use of CS should be promoted for enhanced tooth retention.