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The Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has triggered an international pandemic that has led to significant public health problems. To date, limited evidence exists to suggest that drugs are effective against the disease. As possible treatments are being investigated, herbal medicines have shown potential for producing novel antiviral agents for the COVID-19 disease. Aim This review explored the potential of Malawi’s traditional medicinal plants for the management of COVID-19. MethodsThe authors searched on PubMed and Google scholar for medicinal plants that are used in Malawi and published in openly available peer reviewed journals. Plants linked with antiviral treatment, anti-COVID-19 activity or COVID-19 symptoms management were targeted. These included activity against pneumonia, inflammation, cough, difficulty in breathing, pain/aches, fever, diarrhoea, rheumatism, fatigue, asthma, immunocompromised and cardiovascular diseases.Results11 studies were found with 306 plant species. 127 plant species had at least one COVID-19 related pharmacological activity. Of these plant species, the number of herbal entities used for each indication was: pain/aches (87), fever (2), pneumonia (9), breathing/asthma problems (5), coughing (11), diarrhoea (1), immunosuppression (8), blood issues (10), fatigue (2), heart problems (11), inflammation (8), rheumatism (10) and viral diseases (12). Thirty (30) species were used for more than one disease and Azedarachta indica topped the list (6 of the 13 COVID-19 related diseases). The majority of the species had phytochemicals known to have antiviral activity or mechanisms of actions linked to COVID-19 and consequent diseases’ treatment pathways.ConclusionMedicinal plants are a promising source of compounds that can be used for drug development of COVID-19 related diseases. This review highlights potential targets for the World Health Organization and other research entities to explore in order to assist in controlling the pandemic.

Background:The study aimed at assessing total alkaloids content (TAC), total flavonoids content (TFC), total phenolic content (TPC), antioxidant activity (AA) and predominant individual phenolic compounds in methanol extracts of M. oleifera, S.singueana, M.azedarach leaves and stem barks of L. discolor collected during different seasons of the year. Materials and Methods: TPC, TFC and TAC were analyzed using the Folin Ciocalteau assay, aluminum chloride assay and bromocresol green assay, respectively. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) techniques were used to analyse AA. Phenolic compounds; Vanillic acid, (+)-catechin, quercetin, rutin, sinapic acid, 2,4-hydroxybenzoic acid and ferulic acid were analyzed using high performance liquid chromatography diode array detector (HPLC -DAD). Results: Barks of L. discolour exhibited high levels of TPC, TFC, TAC and AA during hot-dry season (summer) as compared to S. singueana, M. oleifera and M. azedarach leaves which showed significantly (p< 0.05) higher levels in hot-wet season (rainy). Levels of TPC, TFC and TAC were significantly (p< 0.05) influenced by seasonal variations and correlated with levels of AA. Profiles of all phenolic compounds analyzed were not similar in terms of chemical composition and concentration during different seasons. Sinapic acid and 2,4-hydroxybenzoic acid were predominant in S. singueana while sinapic acid and ferulic acid were predominant in M. oleifera. Vanillic acid and 2,4-hydroxybenzoic acid were predominant in L. discolor and M. azedarach respectively. Conclusion: The phytochemical constituents in medicinal plants are subject to seasonal variations which in turn influence the optimum season of harvesting.

Background: In Malawi, cancer is one of the leading causes of morbidity and mortality. This has led to increased use of herbal medicines for cancer management. Objective: This study aimed at identifying medicinal plants that are used for the management of cancer in the southern area of Karonga district, Northern Malawi. Methods: Semi-structured individual questionnaire interviews were used to collect ethnobotanical data from traditional herbal practitioners in the study area. Results: A total of twenty-six (26) plant species from seventeen (17) botanical families were reported by Traditional Herbal Practitioners to be effective in the management of cancer. The botanical families with the representation of more than one plant species were Fabaceae with five species, followed by Combretaceae and Anacardiaceae with tree species each and Meliaceaewith two species. The relative frequency of citation (RFC) showed that Senna singueana (RFC = 0.833), Lannea discolour (RFC = 0.833), Melia azedarach (RFC = 0.667), and Moringa oleifera (RFC = 0.667) were the medicinal plant species that were frequently mentioned and used in the study. The recipes could be a mixture of plant species or plant parts such as the leaves, barks, roots, rhizomes, seeds, flowers, and fruits. Conclusion: The study showed that a potential cancer management drug could be developed from the medicinal plant species found in the area. The results of this study could provide baseline information on medicinal plant species for further phytochemical studies and other studies to validate their use.

Background: Plant foods, as functional foods, provide not only the essential nutrients needed to sustain life, but also bioactive compounds (phytochemicals) for health promotion and disease prevention.Objective of the study: The aim of this research was to screen phytochemicals in commonly consumed fruits and vegetables in Malawi. The effect of processing vegetables on phytochemicals was also evaluated.Methods: The potential of some commonly consumed fruits and vegetables in their raw and cooked forms as natural source of phytochemicals was evaluated in both aqueous and methanol extracts. These fruits and vegetables were screened for alkaloids, saponin, tannins, flavonoids, quinones, coumarins, terpenoids, steroids, glycosides and anthocyanins, total flavonoids content (TFC) and total phenol content (TPC) using standard procedures. TPC and TFC were also analyzed using spectrophotometric methods.Results: Almost all the phytochemicals screened were found in some of the studied fruits and vegetables, with indigenous fruits and vegetables having the most, except for glycosides and anthocyanins. TPC in fruits ranged from 715.08mgGAE/g to 21,119.66mgGAE/g, while TFC ranged from 44.10mgQE/g to 434.74mgQE/g in vegetables. TPC of uncooked vegetables ranged from 522.22 mgGAE/g (pumpkin leaves) to 33, 684.66 mgGAE/g (ntoriro), while in cooked vegetables it ranged from 135.93 mgQE/g (bonongwe) to 6817.86 mgQE/g (chisoso). Overall, indigenous vegetables showed higher TPC values in comparison to exotic vegetables. It was also observed that processing of vegetables affected total phenolic compounds differently. In some vegetables, TPC values increased with cooking (pumpkin leaves, bonongwe and chisoso), while in others (cabbage, Chinese and rape) it decreased.Conclusions: The results show that fruits and vegetables can serve as a cheap source of natural antioxidants that could help fight non-communicable diseases, such as hypertension, diabetes, and cancer. As might be expected, a single fruit or vegetable doesn’t contain all the necessary phytochemicals. Therefore, an intake of a mixture of fruits and vegetables is recommended for maximum benefit as functional foods.Keywords: Phytochemicals, fruits, vegetables, total phenolic content, non-communicable diseases