In vitro antiviral activity of twenty-seven medicinal plant extracts from Southwest Nigeria against three serotypes of echoviruses

Abstract

BackgroundEchoviruses, a serotype of enteroviruses, infect millions of people globally and there is no specific drug treatment or vaccine available for its management. The screening of medicinal plants used locally for the treatment of infectious diseases, can provide a reliable option in the discovery of potent therapeutic compounds. This study was carried out to investigate the antiviral activities of 27 medicinal plant extracts, belonging to 26 different plant species, selected from Nigerian ethnobotany, against echovirus 7, 13 and 19 serotypes (E7, E13 and E19, respectively).MethodsThe plants were macerated in methanol and the cytotoxicities of the crude extracts were evaluated on the rhabdomyosarcoma cell line using the MTT assay. The antiviral activity of the plant extracts and fractions against echoviruses (E7, E13, and E19) was determined using the neutralisation assay, an assay that measures the inhibition of cytopathic effect on cell culture.ResultsThe crude extract of Macaranga barteri leaves had the highest cytotoxicity with CC50 value of 0.27 μg/mL. This was followed by Crinum jagus (9.88 μg/mL) and Terminalia ivorensis (12.14 μg/mL). The antiviral screening showed that ten out of the 27 crude plant extracts tested were active on E7 and E19, inhibiting the cytopathic effect of the virus in tissue culture. None of the extracts inhibited the cytopathic effect caused by E13 serotype. Amongst the active plant extracts, the methanol extract of M. barteri leaves had the highest antiviral activity on both E7 and E9 with IC50 values of 0.028 and 0.0017 ng/mL, respectively, followed by the Ageratum conyzoides extract (0.208 μg/mL, E7; 0.006 μg/mL, E19) and Mondia whitei extract (0.038 μg/mL, E7; 0.005 μg/mL, E19). Amongst the fractions of M. barteri, the DCM fraction was most the active and selective on E7 (IC50 = 0.0075 ng/mL; SI = 19,896.54) and E19 (IC50 = 0.0175 ng/mL; SI = 8581.24).ConclusionOur research has demonstrated that Macaranga barteri extracts has potent antiviral activity against echoviruses E7 and E19, and our findings suggest that this extract may have potential as a therapeutic agent in the treatment of enteroviral infections.

Bioassay-guided isolation and structure elucidation of cytotoxic stilbenes and flavonols from the leaves of Macaranga barteri

“…In fact, 9 displayed SI value that is similar to that of vinblastine, indicating that it is only two to three times more cytotoxic to the cancer cells than the PNT2 cells. Recent studies have revealed the promising antibacterial, antifungal, antiprotozoal and antiviral activities of the extract of the leaves of M. barteri, and stated that at the tested doses, the extract could be considered relatively safe and non-toxic [40][41][42]. The antiproliferative activity of the DCM fraction of M. barteri reported herein and the abundance of cytotoxic compounds in this plant may provide evidence for its use in folklore medicine for the treatment of various cancers.…”

Effect of Flavonoid-Coated Gold Nanoparticles on Bacterial Colonization in Mice Organs

“…Medicinal plants are a good source of potent and safe natural extracts that could act as adjuvants or even be an alternative to costly antibiotics against which microbes are becoming resistant day by day. Moreover, these extracts are cost-effective and work effectively against a variety of microbes, including bacteria, fungus, and viruses [ 51 , 52 , 53 ].…”

Medicinal Plants Used in Four Local Government Areas of Southwestern Nigeria for the Management of Diabetes and Its Comorbidities: An Ethnobotanical Survey

“…Medicinal plants have wide patronage due to their accessibility, potency and affordability. There have been several reports of successful treatment of various disease conditions with herbal therapy (28)(29)(30)(31). In the present study, 77 medicinal plants belonging to76 genera in 44 plant families were used by the respondents in the management of DM and its co-morbidities.…”