Antibacterial, Antioxidant and Anti-inflammatory Properties of Margaritaria discoidea, a Wound Healing Remedy from Ghana

Margaritaria nobilis L.f. (Phyllanthaceae) Ethanolic Extract: Low Acute Oral Toxicity and Antinociceptive Activity

Margaritaria nobilis L.f. (Phyllanthaceae), a native Brazilian tree occurring mainly in the Amazon, is used in folk medicine for the treatment of abscesses (bark) and cancer-like symptoms (leaves). The present study evaluates the safety of its acute oral administration and its effects on nociception and plasma leakage. The chemical constitution of the leaf's ethanolic extract is determined by ultra-performance liquid chromatography-high-resolution mass spectrometry (LC-MS. Its acute oral toxicity is evaluated in female rats at a dose of 2000 mg/kg, evaluating the occurrence of deaths and Hippocratic, behavioral, hematological, biochemical, and histopathological changes, as well as food and water consumption and weight gain. Antinociceptive activity is evaluated in male mice with acetic-acid-induced peritonitis (APT) and formalin (FT) tests. An open field (OF) test is performed to verify possible interferences in the animals' consciousness or locomotion. LC-MS analysis shows the presence of 44 compounds classified as phenolic acid derivatives, flavonoids and O-glycosylated derivatives, and hydrolyzable tannins. No deaths or significant behavioral, histological, or biochemical changes are observed in the toxicity assessment. In nociception tests, M. nobilis extract significantly reduces abdominal contortions in APT, demonstrating selectivity for inflammatory components (FT second phase), not interfering in neuropathic components (FT first phase) or consciousness and locomotion levels in OF. Additionally, M. nobilis extract inhibits plasma acetic-acid-induced leakage. These data demonstrate the low toxicity of M. nobilis ethanolic extract, as well as its effectiveness in modulating inflammatory nociception and plasma leakage, possibly related to the flavonoids and tannins present in its composition.

Medicinal plants used for the management of respiratory diseases in Zimbabwe: Review and perspectives potential management of COVID-19

Respiratory diseases have in the recent past become a health concern globally. More than 523 million cases of coronavirus disease (COVID19), a recent respiratory diseases have been reported, leaving more than 6 million deaths worldwide since the start of the pandemic. In Zimbabwe, respiratory infections have largely been managed using traditional (herbal) medicines, due to their low cost and ease of accessibility. This review highlights the plants' toxicological and pharmacological evaluation studies explored. It seeks to document plants that have been traditionally used in Zimbabwe to treat respiratory ailments within and beyond the past four decades. Extensive literature review based on published papers and abstracts retrieved from the online bibliographic databases, books, book chapters, scientific reports and theses available at Universities in Zimbabwe, were used in this study. From the study, there were at least 58 plant families comprising 160 medicinal plants widely distributed throughout the country. The Fabaceae family had the highest number of medicinal plant species, with a total of 21 species. A total of 12 respiratory ailments were reportedly treatable using the identified plants. From a total of 160 plants, colds were reportedly treatable with 56, pneumonia 53, coughs 34, chest pain and related conditions 29, asthma 25, tuberculosis and spots in lungs 22, unspecified respiratory conditions 20, influenza 13, bronchial problems 12, dyspnoea 7, sore throat and infections 5 and sinus clearing 1 plant. The study identified potential medicinal plants that can be utilised in future to manage respiratory infections.

Margaritaria nobilis L.F. (Phyllanthaceae): Ethnopharmacology and Application of Computational Tools in the Annotation of Bioactive Molecules

Margaritaria nobilis is a shrubby species widely distributed in Brazil from the Amazon to the Atlantic Rainforest. Its bark and fruit are used in the Peruvian Amazon for disinfecting abscesses and as a tonic in pregnancy, respectively, and its leaves are used to treat cancer symptoms. From analyses via UHPLC-MS/MS, we sought to determine the chemical profile of the ethanolic extract of M. nobilis leaves by means of putative analyses supported by computational tools and spectral libraries. Thus, it was possible to annotate 44 compounds, of which 12 are phenolic acid derivatives, 16 are O-glycosylated flavonoids and 16 hydrolysable tannins. Among the flavonoids, although they are known, except for kaempferol, which has already been isolated from this species, the other flavonoids (10, 14, 15, 21, 24–26, 28–30, 33–35, 40 and 41) are being reported for the first time in the genus. Among the hydrolysable tannins, six ellagitannins present the HHDP group (6, 19, 22, 31, 38 and 43), one presents the DHHDP group (5), and four contain oxidatively modified congeners (12, 20, 37 and 39). Through the annotation of these compounds, we hope to contribute to the improved chemosystematics knowledge of the genus. Furthermore, supported by a metric review of the literature, we observed that many of the compounds reported here are congeners of authentically bioactive compounds. Thus, we believe that this work may help in understanding future pharmacological activities.

Anti-seizure effects of medicinal plants in Malawi on pentylenetetrazole-induced seizures in zebrafish larvae

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants are used to manage and treat epilepsy in Malawi because of traditional beliefs and barriers to conventional anti-seizure drugs. Among the plants prescribed by traditional medical practitioners are Margaritaria discoidea, Dalbergia boehmii, Dalbergia nitidula, Catunaregam spinosa, and Lannea discolor. Despite the wide use of these plants, there is a lack of scientific evidence to support their anti-seizure efficacy.

AIM OF THE STUDY

This study used the pentylenetetrazole (PTZ)-induced larval zebrafish seizure model to screen for anti-seizure effects of a collection of medicinal plants traditionally used in Malawi.

MATERIALS AND METHODS

Zebrafish larvae were incubated in decoctions at maximum tolerated concentrations for 18 h and exposed to PTZ. As a primary screen, the effects of the decoctions on seizure-induced locomotor activity were determined. Decoctions that significantly reduced total distance traveled were further checked for effects on seizure latency and frequency, brain activity, immediate early gene expression, and c-fos protein expression.

RESULTS

M. discoidea male leaves, D. boehmii roots, and D. nitidula leaves showed significant anti-seizure effects in the primary screen and were selected for further study. Electrophysiological and immediate early gene analyses corroborated anti-seizure effect of D. boehmii and D. nitidula. The results of c-fos protein expression further suggested that the anti-seizure effects in the larval brain may be mediated by the suppression of neurons localized in midbrain regions.

CONCLUSIONS

These findings provide pioneering scientific evidence of the presence of anti-seizure activity in M. discoidea, D. boehmii, and D. nitidula, prescribed by traditional Malawian medical practitioners. Further studies are needed to identify and isolate compounds responsible for such biological activities and elucidate the possible mechanisms of action.

Medicinal Plants Used in the Ejisu-Juaben Municipality, Southern Ghana: An Ethnobotanical Study

Background: The in-depth traditional knowledge of medicinal plants is at risk of extinction due to the dependency on oral transmission, and as such, there is an urgent need to document such knowledge. This study aimed to document indigenous uses of medicinal plants among community members in the Ejisu-Juaben Municipality. Methods: Data was collected in 2016 from community members and local herbalists in the Ejisu-Juaben Municipality through a semi-structured questionnaire. Statistical tools and ethnobotanical indices, i.e., informant consensus factor (ICF), fidelity level (FL), and use value (UV) were used to analyse the data. Results: One hundred and six medicinal plants belonging to 45 families were reported to cure 68 different human diseases. The most frequently used plant part in this study was the leaves (52%). Decoction (57.5%) and oral administration (58.3%) were the most utilised herbal preparation and administration route respectively. Cleistopholis patens had the highest UV (0.54) with pain & fevers and skin diseases having the highest ICF values (0.88 and 0.85 respectively). Furthermore, new medicinal uses of Hilleria latifolia and ten other species were recorded for the treatment of the traditional local disease, aseram. Conclusions: The current knowledge and uses of medicinal plants are still high in the study area based on the high degree of consensus among informants. This study could allow for the preservation of knowledge and biodiversity of medicinal plants, both of which are threatened with extinction.

Review on medicinal plants and natural compounds as anti-Onchocerca agents

Onchocerciasis is a filarial vector borne disease which affects several million people mostly in Africa. The therapeutic approach of its control was based on a succession of drugs which always showed limits. The last one: ivermectin is not the least. It was shown to be only microfilaricidal and induced resistance to the human parasite Onchocerca volvulus. The approach using medicinal plants used in traditional medicine is a possible alternative method to cure onchocerciasis. Onchocerca ochengi and Onchocerca gutturosa are the parasite models used to assess anthelmintic activity of potentially anthelmintic plants. Numerous studies assessed the in vitro and/or in vivo anthelmintic activity of medicinal plants. Online electronic databases were consulted to gather publications on in vitro and in vivo studies of anti-Onchocerca activity of plants from 1990 to 2017. Globally, 13 plant families were investigated for anti-Onchocerca activity in 13 studies. The most active species were Anacardium occidentale, Euphorbia hirta and Acacia nilotica each with an LC₅₀ value of 2.76, 6.25 and 1.2 μg/mL, respectively. Polycarpol, voacamine, voacangine, ellagic acid, gallic acid, gentisic acid, 3-O-acetyl aleuritolic acid and (-)-epigallocatechin 3-O-gallate were the isolated plant compounds with anti-Onchocerca activity. Most of the assessed extract/compounds showed a good safety after in vivo acute toxicity assays and/or in vitro cytotoxicity test. The exception was the ethanol extract of Trichilia emetica, which killed completely and drastically mice at a dose of 3000 mg/kg. Several plant groups of compounds were shown active against Onchocerca sp. such as tannins, alkaloids, triterpenoids and essential oils. Nevertheless, none of the active compounds was subjected to clinical trial, to assessment of its diffusibility through nodular wall or its capability to induce genetic resistance of Onchocerca sp.

Antiinflammatory properties of betulinic acid and xylopic acid in the carrageenan-induced pleurisy model of lung inflammation in mice

This study investigated the antiinflammatory properties of betulinic acid (BA) and xylopic acid (XA) extracted from Margaritaria discoidea and Xylopia aethiopica, respectively. M. discoidea and X. aethiopica are plants native in Ghana and the West-African region and used traditionally to treat different pathologies including inflammatory conditions. The antiinflammatory effect of BA and XA was established by an in vivo assay using the carrageenan-induced pleural inflammation model in mice. Also, the ability of BA and XA to increase catalase, superoxide dismutase, glutathione levels and decrease lipid peroxidation level in reactive oxidative assays was assessed. In addition, the ability of XA and BA to prevent potential lung tissue damage was quantified. Pretreatment with BA and XA reduced significantly, signs of inflammation: neutrophil infiltration, oedema, and alveoli septal thickening in carrageenan-treated lung tissue. Additionally, BA or XA pretreatment lowered the degree of lipid peroxidation in the lung tissue while increasing the levels of catalase, superoxide dismutase, and glutathione in vivo. Comparatively, XA was more efficacious than BA in the prevention of lung tissue damage. BA and XA derived from X. aethiopica and M. discoidea possess antiinflammatory and in vivo antioxidant activities in mice pleurisy model. The effect of these compounds gives credence to the traditional use in the management of inflammatory conditions of the airway.

Cytotoxicity of 91 Kenyan indigenous medicinal plants towards human CCRF-CEM leukemia cells

ETHNOPHARMACOLOGICAL RELEVANCE

Plants from Kenyan flora are traditionally used against many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. Recently there are recommendations that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants that treat cancer.

AIM

The present study was aimed at investigating the cytotoxicity of a plethora of 145 plant parts from 91 medicinal plants, most of which are used in the management of cancer and related diseases by different communities in Kenya, against CCRF-CEM leukemia cell line.

MATERIALS AND METHODS

Extracts from different plant parts (leaves, stems, stem bark, roots, root barks, aerial parts and whole herb) were obtained by cold percolation using different solvent systems, such as (1:1v/v) dichloromethane (CH2Cl2) and n-hexane (1), methanol (MeOH) and CH2Cl2 (2); neat MeOH (3), 5% H2O in MeOH (4) and with ethanol (EtOH, 5); their cytotoxicities were determined using the resazurin reduction assay against CCRF-CEM cells.

RESULTS

At a single concentration of 10μg/mL, 12 out of 145 extracts exhibited more than 50% cell inhibition. These include samples from the root bark of Erythrina sacleuxii (extracted with 50% n-hexane-CH2Cl2), the leaves of Albizia gummifera, and Strychnos usambarensis, the stem bark of Zanthoxylum gilletii, Bridelia micrantha, Croton sylvaticus, and Albizia schimperiana; the root bark of Erythrina burttii and E. sacleuxii (extracted with 50% CH2Cl2-MeOH), the stem bark of B. micrantha and Z. gilletii (extracted using 5% MeOH-H2O) and from the berries of Solanum aculeastrum (extracted with neat EtOH). The EtOH extract of the berries of S. aculeastrum and A. schimperiana stem bark extract displayed the highest cytotoxicity towards leukemia CCRF-CEM cells, with IC50 values of 1.36 and 2.97µg/mL, respectively. Other extracts having good activities included the extracts of the stem barks of Z. gilletii and B. micrantha and leaves of S. usambarensis with IC50 values of 9.04, 9.43 and 11.09µg/mL, respectively.

CONCLUSIONS

The results of this study provided information related to the possible use of some Kenyam medicinal plants, and mostly S. aculeastrum, A. schimperiana, C. sylvaticus, Z. gilletii, B. micrantha and S. usambarensis in the treatment of leukemia. The reported data helped to authenticate the claimed traditional use of these plants. However, most plants are used in combination as traditional herbal concoctions. Hence, the cytotoxicity of corresponding plant combinations should be tested in vitro to authenticate the traditional medical practitioners actual practices.

Flavonoid glycosides from the stem bark of Margaritaria discoidea demonstrate antibacterial and free radical scavenging activities

One new flavonoid glycoside, along with three known flavonoid glycosides were isolated from the stem bark of Margaritaria discoidea, which is traditionally used in the management of wounds and skin infections in Ghana. The new flavonoid glycoside was elucidated as hydroxygenkwanin-8-C-[α-rhamnopyranosyl-(1 → 6)]-β-glucopyranoside (1) on the basis of spectroscopic analysis. The isolated compounds demonstrated free-radical scavenging as well as some level of antibacterial activities. Microorganisms including Staphylococcus aureus are implicated in inhibiting or delaying wound healing. Therefore, any agent capable of reducing or eliminating the microbial load present in a wound as well as decreasing the levels of reactive oxygen species may facilitate the healing process. These findings therefore provide some support to the ethnopharmacological usage of the plant in the management of wounds.