Antimicrobial Activity of Zingiber officinale (Ginger) Extract against Escherichia coli and Staphylococcus aureus Isolated from Vegetables Sold in Bokkos Market Plateau State, Nigeria

Abstract

The growing threat of antibiotic resistance has intensified the search for alternative natural antimicrobials with broad-spectrum efficacy. This research aimed to assess the effectiveness of ginger rhizome extracts against Staphylococcus aureus and Escherichia coli bacteria found in vegetables obtained from Bokkos Local government area of Plateau State, Nigeria. The research determined the extract’s minimum inhibitory concentration (MIC) to evaluate its potency against the identified bacterial strains. The ethanol extract of ginger inhibited the growth of S. aureus at various concentrations: 400 mg/ml resulted in a 20 mm clear zone, 200 mg/ml showed an 18 mm clear zone, 100 mg/ml displayed a 14 mm clear zone, and 50 mg/ml showed a 12 mm clear zone. However, compared to the standard ciprofloxacin (20mg/ml), the inhibition of S. aureus growth was lesser at all concentrations of the ginger extract, with a clear zone of 38 mm. Similarly, the ethanol extract of ginger rhizome showed inhibition against E. coli, with clear zones averaging 19 mm at 400 mg/ml, 16 mm at 200 mg/ml, 13 mm at 100 mg/ml, and 11 mm at 50 mg/ml, in contrast to the 44 mm produced by the standard Ciprofloxacin (20 mg/ml). Overall, the ethanol extract of ginger rhizome demonstrated a broad-spectrum antibacterial activity, ranging from 11 mm to 20 mm of inhibition zone. Thus, there was a very high significant difference (F = 170.53, df = 4, Adj.R² = 97.27%, P < 0.001) in the mean zones of inhibition across the treatment groups. The maximum average inhibition against both Escherichia coli and Staphylococcus aureus was observed at 400 mg/ml concentration, while the minimum inhibition was noted at 50 mg/ml concentration. This study indicates that the ethanol extract of ginger rhizome possesses bacteriostatic properties against both gram-positive and gram-negative E. coli and S. aureus, which are commonly known as multi-drug resistant microorganisms.