Abstract
This study investigated the phytochemical composition and antibacterial activity of Zingiber officinale rhizome extracts obtained using solvents of different polarities (methanol, ethyl acetate, chloroform, dichloromethane, and n-hexane). GC-MS identified 65 volatile and semi-volatile compounds across the five solvent extracts, with methanol providing the broadest chemical coverage. Phenolics and sesquiterpenoid-related compounds were the dominant classes, and gingerol was consistently detected as a major constituent across solvent systems. The antibacterial activity of Z. officinale methanol extracts was evaluated against Vibrio parahaemolyticus using agar well diffusion and resazurin-based microdilution assays. The methanolic extract showed a clear concentration-dependent antibacterial effect against V. parahaemolyticus, with inhibition zones increasing to 19.87 ± 0.29 mm at 500 mg/mL after 48 h. Both MIC and MBC were 7.81 mg/mL, indicating bactericidal activity under the tested conditions. The above data illustrate that the potential of ginger-derived extracts as candidates for developing herbal preparations for aquaculture biosecurity, especially, controlling the Vibrio diseases in shrimps as well as contributing to reduce antibiotic reliance and improving sustainability in shrimp aquaculture in Vietnam and worldwide.