ANTIOXIDANT

EVALUATION OF ANTIOXIDANT CAPACITY, PHYTOCHEMICAL ACTIVITY OF THE AQUEOUS AND ETHANOLIC EXTRACT OF Bryophyllum pinnatum

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Abstract
Bryophyllum pinnatum, commonly known as “Miracle Leaf,” has long been employed in traditional medicine for the treatment of infections and various oxidative stress-related ailments. This study aimed to evaluate and compare the phytochemical composition, antioxidant capacity, and antimicrobial activity of the aqueous and ethanol leaf extracts of B. pinnatum. Fresh leaves were collected, authenticated, air-dried, pulverized, and subjected to Soxhlet extraction using ethanol and distilled water. The extraction yields were determined, revealing a higher yield for the aqueous extract (18.3%) compared to the ethanol extract (14.3%). Preliminary qualitative phytochemical screening indicated the presence of diverse bioactive compounds, including alkaloids, flavonoids, phenols, tannins, saponins, glycosides, terpenoids, steroids, and anthraquinones in both extracts. Quantitative analysis showed that the ethanol extract contained higher concentrations of flavonoids (31.63 mg/g), phenolics (37.06 mg/g), and alkaloids (21.06 mg/g), whereas the aqueous extract exhibited elevated saponin content (31.57 mg/g). The antioxidant potential of the extracts was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP) assays. The ethanol extract demonstrated superior free radical scavenging activity (IC₅₀ = 63.11 µg/mL) and reducing power (345.5 µmol Fe²⁺/g) compared to the aqueous extract, correlating with its higher phenolic and flavonoid contents. ntimicrobial activity was evaluated against clinically relevant pathogens, including Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger using agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration/minimum fungicidal concentration (MBC/MFC) methods. Both extracts displayed dose-dependent, broad-spectrum antimicrobial effects, with Gram-positive bacteria being more susceptible than Gram-negative bacteria, and fungi showing the least sensitivity. Notably, the ethanol extract exhibited greater potency, requiring lower concentrations to inhibit and kill test organisms. These findings collectively validate the ethnomedicinal use of B. pinnatum and highlight the influence of extraction solvent on bioactivity. The study underscores the potential of the ethanol leaf extract as a promising source of natural antioxidants and antimicrobial agents, warranting further pharmacological and mechanistic investigations for therapeutic development
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PHYTOCHEMICAL AND ANTIOXIDANT PROFILE OF MONODORA MYRISTICA SEED EXTRACT

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Abstract
Monodora myristica (calabash nutmeg) is a widely used West African spice with traditional medicinal and preservative applications. This study presents a deep evaluation of its phytochemical composition and antioxidant potential. Quantitative phytochemical analysis revealed that flavonoids were strongly present (Mean ± SEM: 0.8216 ± 0.00072), indicating a high concentration likely responsible for the extract’s potent free-radical scavenging activity. Terpenoids (0.2091 ± 0.2183) and cardiac glycosides (0.5091 ± 0.5136) were moderately detected, suggesting contributions to the spice’s aromatic, anti-inflammatory, antimicrobial, and cardiotonic properties. Alkaloids (0.2725 ± 0.2734) and steroids (0.1940 ± 0.2560) were present at low to moderate levels, supporting traditional analgesic, antimicrobial, anti-inflammatory, and membrane-stabilizing activities. Antioxidant activity was evaluated using a multi-assay approach, including DPPH, hydrogen peroxide (H₂O₂) scavenging, ferric reducing antioxidant power (FRAP), nitric oxide (NO) scavenging, total antioxidant capacity (TAC), and reducing power (RP), with ascorbic acid as the standard. The extract demonstrated strong, concentration- dependent DPPH scavenging (21.41–87.27%) and progressively enhanced reducing power (76.05–88.12%), reflecting effective hydrogen donation and electron-transfer capacity. NO scavenging was highest at low concentrations (85.45%) but declined at higher doses, while TAC showed moderate and consistent activity (82.99–86.93%). H₂O₂ scavenging remained relatively low (15.35–17.75%), and FRAP displayed a decreasing trend with increasing concentration (82.49% → 25.03%), likely due to matrix interactions affecting iron reduction. Across all assays, ascorbic acid maintained high and stable antioxidant performance (>95%). These findings suggest that Monodora myristica is rich in bioactive phytochemicals with significant antioxidant potential, capable of neutralizing free radicals and supporting cellular redox balance. This study also reinforces the spice’s traditional medicinal relevance and highlights its promise as a natural source of antioxidants for nutraceutical, therapeutic, and food preservation applications.
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co-supervisor