Muendi Sigidi

Dr. Muendi Sigidi


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

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

Representative Publications

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28 September 2021 in Biochemistry Research International
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XMX. E. Mabasa
X. E. Mabasa
LML. M. Mathomu
L. M. Mathomu
NMN. E. Madala
N. E. Madala
EME. M. Musie
E. M. Musie
MSMuendi Sigidi
Muendi Sigidi
Momordica balsamina (M. balsamina) is a medicinal herb comprising health-promoting secondary metabolites. This study was aimed to profile bioactive compounds in the methanolic extract of M. balsamina leaves using molecular spectroscopic (UV-Vis and FTIR) and hyphenated chromatographic (UHPLC-qTOF-MS) techniques and evaluate the biological (in vitro anti-inflammatory and cytotoxicity) activities of the extract. The preliminary phytochemical screening tests revealed the presence of cardiac glycosides, flavonoids, saponins, tannins, and terpenoids. The UV-Vis profile revealed various absorption bands ranging from 200 to 750nm, indicating the presence of flavonoids, phenolic compounds, tannins, terpenoids, carotenoids, chlorophyll, and alkaloids. FTIR spectra confirmed the presence of alkaloids, flavonoids, terpenes, anthraquinones, and phenolic compounds. A high-resolution and accurate mass spectrometer (LC-QTOF-MS model LC-MS-9030 instrument) was used, and the results confirmed the presence of flavonoid aglycones, such as quercetin, isorhamnetin, and kaempferol, as well as pseudolaroside A and dicaffeoylquinic and feruloyl isocitric acids. To the best of our knowledge, this is the first report of pseudolaroside A dimer and feruloyl isocitric acid in M. balsamina leaves. In vitro cytotoxicity assay showed that the extract was nontoxic against human colorectal adenocarcinoma (HT29 and Caco2), Vero, and RAW 264.7 cells. However, the extract showed anti-inflammatory activity on RAW 264.7 cells. The study confirmed that M. balsamina leaves contain nontoxic secondary metabolites that may play a pivotal role in human health as anti-inflammatory agents.

29 May 2018 in Molecules
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CAChinedu Anokwuru
Chinedu Anokwuru
MSMuendi Sigidi
Muendi Sigidi
MBMarlaine Boukandou
Marlaine Boukandou
MTMilingoni Peter Tshisikhawe
Milingoni Peter Tshisikhawe
ATAfsatou Ndama Traore
Afsatou Ndama Traore
NPNatasha Potgieter
Natasha Potgieter
The aim of this study was to determine the antioxidant activity of the extractable and non-extractable phenolics of Terminalia. Sericea Burch. Ex DC. Free, ester bound, ether or glycoside bound and insoluble phenolics were extracted from the fruit, leaves, stem, and root samples. Follin Ciocalteu was used to estimate the phenolic content while DPPH (2,2-diphenyl-1-picrylhydrazyl) assay was used to determine the antioxidant activity. The data obtained were subjected to multivariate analysis for relationships. The result indicated that the highest average total phenolic contents and antioxidant activities were found in the free (14.8 mgGAE/g; IC50 6.8 μg/mL) and ester bound (15.1 mgGAE/g; IC50 6.4 μg/mL) extractable phenolics. There was a strong negative correlation between TPC and DPPH (r = −0.828). Agglomerative hierarchical clustering revealed three clusters. Cluster one contained the insoluble and glycoside phenolics while cluster 2 contained only free phenolic acid of the root. The third cluster was predominantly free and ester bound phenolic extracts. The principal component analysis score plot indicated two major clusters with factor 1 (F1) explaining 61% of the variation. The nuclear magnetic resonance spectroscopy spectra indicated that gallic acid and resveratrol are the major phenolic compounds present in the root. This study has demonstrated that extractable phenolics contributed more to the antioxidant activities compared to the non-extractables.

6 March 2025 in Plants
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MMMatshoene Violet Motene
Matshoene Violet Motene
CMCharity Maepa
Charity Maepa
MSMuendi Sigidi
Muendi Sigidi
The green synthesis of silver nanoparticles (AgNPs) using Elephantorrhiza elephantina (Burch) bulb extracts and evaluation of their antimicrobial, cytotoxic, and antioxidant properties were investigated. The crude plant extracts were prepared using distilled water, ethanol, and methanol for a comparison. Silver nanoparticles were synthesized and characterized via UV–Visible spectroscopy (UV–VIS), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The formation of silver nanoparticles was confirmed using the UV–VIS spectra at 550 nm. The TEM confirmed the nanoparticle morphology as a mixed dispersed sphere, oval, and triangular shapes with a size range of 7.8 nm to 31.3 nm. The secondary metabolites were detected using TLC, DPPH, and LC-MS. Antimicrobial activity was assessed based on agar-well diffusion; cytotoxicity was examined through MTS assays. Various phytochemical constituents were detected through TLC and LC-MS. The crude extracts and methanol-extract-capped AgNP were able to scavenge free radicals, as shown by the developments of inhibitory bands on the TLC plate. The agar well diffusion test revealed that the AgNP capped methanol extract had potent antimicrobial activity against Gram-positive and Gram-negative multidrug resistant bacteria in comparison with penicillin and neomycin, with inhibition zones ranging between 10 mm and 14 mm for the methanol-extract-capped AgNP. The in vitro MTS assay revealed that methanol crude extracts and methanol-extract-capped AgNP had a less cytotoxic effect on the HEK293 cells in comparison with untreated cells (control). We therefore conclude that methanol was the best reducing solvent with the best overall nanoparticle morphology and performance in antimicrobial and cytotoxicity, in comparison to ethanol and distilled water.