N.A. OLISE

Antimicrobial resistance poses a major threat to global health, necessitating the exploration of alternative therapeutic options from natural sources. This study evaluated the antimicrobial activity of the methanolic extract of brown mustard seed against selected clinical isolates. The antimicrobial activity of the extract was tested at concentrations ranging from 50–600 mg/ml using agar well diffusion assay. The Minimum Inhibitory Concentration (MIC), minimum bactericidal concentration (MBC), and Minimum Fungicidal Concentration (MFC) were determined using broth dilution and subculture techniques. Phytochemical screening was conducted to identify the bioactive constituents of the extract. Data were analyzed using SPSS version XX, with chi-square tests applied to assess associations between extract concentrations and microbial growth responses. The results revealed that Staphylococcus aureus recorded the highest mean zone of inhibition (17.50 ± 2.49 mm), followed by Candida albicans (8.67 ± 4.26 mm), while Escherichia coli (6.50 ± 2.95 mm) and Pseudomonas aeruginosa (6.00 ± 4.10 mm) showed lower susceptibility. Post hoc analysis indicated concentration-dependent inhibition in Candida albicans and Escherichia coli, while inhibition of Pseudomonas aeruginosa was observed only at the highest concentration. MIC values were established at 100 mg for Staphylococcus aureus, 400 mg for Escherichia coli and P. aeruginosa, and 600 mg for Candida albicans. MBC values confirmed bactericidal activity at 100 mg for Staphylococcus aureus and 600 mg for Escherichia coli and Pseudomonas aeruginosa, whereas the MFC for Candida albicans was 600 mg. Phytochemical analysis revealed the presence of alkaloids, flavonoids, terpenes, steroids, tannins, phenols, and resins, with saponins absent. These findings demonstrate that brown mustard seed possesses broad-spectrum antimicrobial properties, with S. aureus being the most sensitive organism, supporting its potential as a source of plant-based antimicrobial agents.

Urinary tract pathogens are increasingly resistant to conventional antibiotics, prompting interest in plant-derived bioactive agents. This study evaluated the phytochemical profile and antibacterial potential of Cinnamomum tamala bark extracts against selected clinical isolates. Dried bark samples were subjected to aqueous and ethanolic extraction, followed by phytochemical screening using GC–MS analysis. Antimicrobial activity was carried out using ditch plate and agar well diffusion methods, while minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined via agar dilution techniques. The ethanolic extract demonstrated concentration-dependent inhibition, with zones of inhibition ranging from 8.25 ± 4.8 mm at 50 µg/mL to 21.75 ± 2.93 mm at 800 µg/mL, showing significant differences across concentrations (p = 0.034). The aqueous extract exhibited no effect at low concentrations but was active at higher concentration, producing inhibition zones up to 6.50 ± 3.77 mm, significantly different across groups (p < 0.001). MIC results indicated stronger activity for the ethanolic extract, particularly against E. coli (12.5 µg/mL), compared to the aqueous extract, which required higher concentrations (100–200 µg/mL) across organisms. Similarly, ethanolic MBC values ranged between 25–100 µg/mL, significantly lower than the consistent 200 µg/mL required for the aqueous extract. Phytochemical screening revealed alkaloids, flavonoids, tannins, terpenoids, and phenols in both extracts, while saponins and glycosides were exclusive to the aqueous extract, and steroids and resins were unique to the ethanolic extract. GC–MS analysis identified major constituents including Squalene (21.13%), 9-Octadecenoic acid (17.62%), and 13-Octadecenal (16.89%) in the ethanolic extract, while the aqueous extract was dominated by 9-Borabicyclo[3.3.1]nonane (28.24%) and Cyclopropane derivatives (17.04%). These findings highlight the potent antibacterial efficacy of C. tamala ethanolic extract, particularly against E. coli, with activity linked to its terpenoid and fatty acid constituents. The results suggest that C. tamala may serve as a promising source of natural antimicrobials.

Urinary tract pathogens are increasingly resistant to conventional antibiotics, prompting interest in plant-derived bioactive agents. This study evaluated the phytochemical profile and antibacterial potential of Cinnamomum tamala bark extracts against selected clinical isolates. Dried bark samples were subjected to aqueous and ethanolic extraction, followed by phytochemical screening using GC–MS analysis. Antimicrobial activity was carried out using ditch plate and agar well diffusion methods, while minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined via agar dilution techniques. The ethanolic extract demonstrated concentration-dependent inhibition, with zones of inhibition ranging from 8.25 ± 4.8 mm at 50 µg/mL to 21.75 ± 2.93 mm at 800 µg/mL, showing significant differences across concentrations (p = 0.034). The aqueous extract exhibited no effect at low concentrations but was active at higher concentration, producing inhibition zones up to 6.50 ± 3.77 mm, significantly different across groups (p < 0.001). MIC results indicated stronger activity for the ethanolic extract, particularly against E. coli (12.5 µg/mL), compared to the aqueous extract, which required higher concentrations (100–200 µg/mL) across organisms. Similarly, ethanolic MBC values ranged between 25–100 µg/mL, significantly lower than the consistent 200 µg/mL required for the aqueous extract. Phytochemical screening revealed alkaloids, flavonoids, tannins, terpenoids, andphenols in both extracts, while saponins and glycosides were exclusive to the aqueous extract, and steroids and resins were unique to the ethanolic extract. GC–MS analysis identified major constituents including Squalene (21.13%), 9- Octadecenoic acid (17.62%), and 13-Octadecenal (16.89%) in the ethanolic extract, while the aqueous extract was dominated by 9- orabicy clo[3.3.1]nonane (28.24%) and Cyclopropane derivatives (17.04%). These findings highlight the potent antibacterial efficacy of C. tamala ethanolic extract, particularly against E. coli, with activity linked to its terpenoid and fatty acid constituents. The results suggest that C. tamala may serve as a promising source of natural antimicrobials.

(garlic) has long been recognized for its antimicrobial potential, yet the comparative efficacy of its ethanolic and aqueous extracts against clinically relevant pathogens requires further evaluation. This study assessed the antibacterial
activity of ethanolic and aqueous garlic extracts against Klebsiella pneumoniae and Pseudomonas aeruginosa isolated from wound swabs. Garlic bulbs were authenticated, dried, pulverized, and subjected to maceration in ethanol and sterile water to obtain crude extracts with yields of 2.25% and 3.57%, respectively. Antimicrobial susceptibility was evaluated using ditch plate, cup plate, and agar dilution methods. Inhibition zone diameters (IZDs), minimum inhibitory concentrations (MICs), and minimum bactericidal concentrations (MBCs) were determined. Both extracts displayed concentration-dependent antibacterial activity, with ethanolic fractions showing greater potency than aqueous fractions. Ethanolic extract inhibited K. pneumoniae and P. aeruginosa at 100 mg/mL (IZD: 12–14 mm), while aqueous extract required 200 mg/mL for measurable inhibition (IZD: 11–13
mm). MIC values were 100 mg/mL for ethanolic and 200 mg/mL for aqueous extracts, whereas MBC was achieved only with ethanolic extract at 200 mg/mL. Statistical analysis confirmed that concentration significantly influenced antibacterial activity (p = 0.000), while differences between organisms or extract types were not statistically significant (p = 0.292). These findings suggest that garlic exhibits concentration- dependent antibacterial activity, with ethanolic extracts demonstrating superior
efficacy.