Microbiology Research Journal International

Abstract

Objective: Ginger (Zingiber officinale Roscoe) rhizome is a well-known food spice and flavoring ingredient with wide range of medicinal properties. The rhizome of ginger consists of unique secondary metabolites compounds. The study evaluates the secondary metabolites profiling of ginger (Zingiber officinale Roscoe) rhizome using Gas Chromatography-Mass Spectrometry (GC-MS) and its antibacterial potential on Staphylococcus aureus and Escherichia coli.

Methodology: The GC-MS and phytochemical screening of the aqueous ginger (Zingiber officinale Roscoe) rhizome extract were determined using standard procedures. Antibacterial activities were determined by agar well diffusion methods. The minimum inhibitory concentrations (MIC) were determined using standard procedure.

Results: The result of the GC-MS analysis shows that thirty six compounds were identified in the ginger (Zingiber officinale Roscoe) rhizome using GC-MS analysis with tridecane with molecular formula of C₁₃H₂₈ being the most abundant with peak area of 16.94% and retention time of 12.849. The phytochemical screening shows that the plant contains saponins, alkaloids, glycoside, simple phenolics, tannins, flavonoids carbohydrates and reducing sugar. The study shows that at 250 mg/ml, the aqueous ginger extract exhibited little or no response with zone of inhibition of 9.85±0.39 and 8.19±1.33 mg/ml against Staphylococcus aureus and Escherichia coli respectively. The extract exhibited weak response antibacterial activity against E. coli and moderate response against S. aureus with zone of inhibition of 13.62±2.03 and 16.73±1.83 at 500 mg/dl respectively. Augmentin showed moderate and strong response with zone of inhibition of 17.23±1.67 and 21.13±1.34 mg/ml against E. coli and S. aureus at concentration of 7.50 mg/ml respectively. At 15 mg/ml, augmentin showed strong response with zone of inhibition of 23.00±2.88 mg/ml against E. coli and potent response with zone of inhibition of 30.50±2.64 mg/ml against S. aureus. The Minimum inhibitory concentration (MIC) values for the aqueous ginger are 125 and 250 mg/ml for S. aureus and E. coli and 7.81 and 15.63 for augmentin solution for the sane organisms respectively.

Conclusions: The aqueous ginger (Zingiber officinale Roscoe) rhizome contains secondary metabolites and possesses poor antibacterial activity against Staphylococcus aureus and Escherichia coli and may prevent pathogenic diseases caused by these organisms.