David Tryson Tembo

Dr. David Tryson Tembo

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 January 2023 in BioMed Research International
Verified
Journal Article
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BMBonface Mwamatope
Bonface Mwamatope
ICIbrahim Chikowe
Ibrahim Chikowe
DTDavid Tryson Tembo
David Tryson Tembo
JKJohn F. Kamanula
John F. Kamanula
FMFriday F. F. Masumbu
Friday F. F. Masumbu
FKFelix Daire Kumwenda
Felix Daire Kumwenda
The purpose of this study was to investigate the phytochemical composition and antioxidant activity of 17 edible wild fruits that are widely distributed and consumed in Malawi for pharmacological value exploration. Qualitative phytochemical analysis, total phenolic content, total flavonoid content, ferric reducing antioxidant power (FRAP), total antioxidant activity (TAA), and 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity (DPPH) were performed in aqueous and methanolic fruit extracts. The results showed that the extracts contained alkaloids, saponins, terpenoids, glycosides, coumarins, phenolic compounds, tannins, flavonoids, steroids, and quinones. Piliostigma thonningii had the highest total phenolic content (1675.33 ± 12.34 mg GAEg-1 FW) in methanolic extracts, and Annona senegalensis gave the highest levels of total flavonoid content (649.67 ± 2.08 mg RE g-1 FW) in aqueous extracts. The results of antioxidant activities (FRAP, TAA, and DPPH) varied widely, and the variations were significant (P < 0.05). Thespesia garckeana and Mangifera indica exhibited a high ability to chelate metal cations in methanolic extracts and in aqueous extracts, respectively. DPPH levels were higher in aqueous extracts and ranged from 11.07% to 99.61%. This study provides evidence that the studied edible fruits of Malawi have potential as value‐added products for various treatments of oxidative stress‐associated ailments as they contain more phytochemical constituents. We recommend further studies to determine if the presence of a particular class of phytochemicals would translate into the bioactivity capability of these edible fruits.

17 October 2023 in Journal of Herbal Medicine
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Journal Article
Closed access
FMFriday F.F. Masumbu
Friday F.F. Masumbu
BMBonface Mwamatope
Bonface Mwamatope
DTDavid Tryson Tembo
David Tryson Tembo
AMAnthony Mwakikunga
Anthony Mwakikunga
JKJohn Kamanula
John Kamanula

FTFabiano Gibson Daud Thulu
Fabiano Gibson Daud Thulu
DTDavid Tryson Tembo
David Tryson Tembo
RNRowland Nyirongo
Rowland Nyirongo
PMPatrick Joseph Cardinal Mzaza
Patrick Joseph Cardinal Mzaza
AKAllan Kamfosi
Allan Kamfosi
UCUpile Chitete-Mawenda
Upile Chitete-Mawenda
In this study, electric field and magnetic flux density pollution levels were measured in southern Africa, a case of Blantyre City in Malawi, between 2020 and 2021. Sixty short-term measurements were performed using Trifield Electro Magnetic Frequency meter model TF2 in 30 different locations. Five high-population-dense sampling points were selected from school campuses, hospitals, industrial areas, markets, residential areas, and within the commercial and business center (CBC) of Blantyre. Electric field and magnetic flux density pollution monitoring was conducted between 10:00–12:00 h and 17:00–19:00 h for short-range analysis. Short-range results show that the maximum measured electric field pollution were 249.24 mV/m and 207.85 mV/m between 10:00–12:00 and 17:00–19:00 respectively, which are below the public limits of 4200.00 mV/m for public exposure. Similarly, maximum short-range results for magnetic flux density were 0.073 G and 0.057 G between 10:00–12:00 and 17:00–19:00 respectively which are below the public limits of 2 G for public exposure. Both measured electric and magnetic flux density were compared with the International Commission on Non-Ionizing Radiation Protection (ICNIRP), World health organization (WHO), and Institute of electrical and electronics engineers (IEEE). It was determined that all measured values for both electric and magnetic flux density were smaller than set limits for non-ionizing radiation for both public and occupation health. More importantly, these background measurements establish a baseline for future changes to be compared against public safety.

1 May 2022 in Anti-Cancer Agents in Medicinal Chemistry
Verified
Journal Article
Closed access
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DTDavid Tryson Tembo
David Tryson Tembo
BMBonface Mwamatope
Bonface Mwamatope
ICIbrahim Chikowe
Ibrahim Chikowe
CMCecilia Maliwichi-Nyirenda
Cecilia Maliwichi-Nyirenda
EKElizabeth Kampira
Elizabeth Kampira
FMFriday Foster Masumbu
Friday Foster Masumbu
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 representation of more than one plant species were Fabaceae with five species, followed by Combretaceae and the Anacardiaceae with three species each, and Meliaceaewith with 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 which 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.

2 November 2022 in Journal of Food Quality
Verified
Journal Article
Open access
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JMJames Majamanda
James Majamanda
MKMangani Katundu
Mangani Katundu
VNVictoria Ndolo
Victoria Ndolo
DTDavid Tryson Tembo
David Tryson Tembo
Maize has been cultivated and continues to be cultivated for its usability in calorie supply to humans and livestock. There has been great interest in pigmented landrace maize varieties (PLMVs) due to their importance in the pharmaceutical industry. Landraces are to a large extent a repository of the gene pool that enriches biodiversity and maintains but also stabilizes the ecosystem in a sustainable way. PLMVs are still being cultivated by smallholder farmers in smaller portions of their fields and home surroundings despite the high adoption of white hybrid maize. This study examined the ash, moisture, mineral, crude protein, fat, and carbohydrate content of three different PLMVs from central (Ntcheu and Dedza districts) and northern (Mzimba district) Malawi. The mineral content of soils from fields where PLMVs were grown was also analyzed. The study areas experience a warm temperate climate and higher rainfall in summer than in winter but they differ in that Ntcheu has the highest average annual temperature of 20.3C while Dedza receives the highest annual precipitation of about 1010mm. Mzimbas average annual temperature and precipitation are 20.1C and 915mm, respectively. The study showed that orange maize from Dedza had a significantly higher content of calcium (71.000.58 mgkg−1), magnesium (819.000.58mgkg−1), and phosphorus (2720.350.03mgkg−1). Significantly higher contents of zinc (54.610.43mgkg−1) and potassium (808.580.27mgkg−1) were observed in purple maize from Dedza and Ntcheu, respectively. Red maize from Dedza had a significantly higher content of iron (59.800.26mgkg−1). Purple maize from Dedza has significantly higher carbohydrate content (65.520.07). The findings also revealed that red maize from Dedza provenance had a high content of crude protein (12.570.07) and fat (10.730.14). Moisture (17.300.21) and ash (2.280.02) were significantly higher in orange maize from Dedza. Dedzas provenance revealed a high content of the analyzed attributes in PLMVs. Mineral analysis showed different levels of mineral bioavailability in different PLMVs and in the soils where maize was grown. It can, therefore, be concluded that production location and maize variety have an influence on the attributes of PLMVs. Understanding the physicochemical attributes of PLMVs and its maximum utilization have the potential of improving food and nutrition security in Sub-Saharan African countries and globally.

7 October 2022 in Functional Foods in Health and Disease
Verified
Journal Article
Open access
PDF file
VNVictoria Ndolo
Victoria Ndolo
MMMargaret Maoni
Margaret Maoni
BMBonface Mwamatope
Bonface Mwamatope
DTDavid Tryson Tembo
David Tryson Tembo
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