Bioactive Constituents of Curcuma amada Roxb. Rhizome and its Antimicrobial Activity against Food Spoilage Microorganisms

Background: Curcuma amada Roxb. is popularly known as mango ginger due to its morphological similarity to ginger but has raw mango characteristics. It is well known for its several medicinal and pharmacological activities. Objectives: This study aimed to determine the antimicrobial activity of different extracts of Curcuma amada Roxb. rhizome and its phytochemical screening using Gas Chromatography-Mass Spectrometry (GC-MS) method. Materials and Methods: Antimicrobial activity of different C. amada rhizome extracts (acetone, hexane, ethanol and aqueous) were screened against spoilage bacteria and fungi using agar well diffusion method. The spoilage bacteria included Klebsiella oxytoca, Enterobacter mori, Serratia marcescens, Bacillus subtilis and Bacillus inaquosorum, while the spoilage fungi included Penicillium citrinum, Alternaria alstroemeriae, Aspergillus welwitschiae, Aspergillus awamori and Aspergillus aflatoxiformans. Results: C. amada rhizome ethanolic extract showed significant inhibitory activity against spoilage microorganisms at 10 mg/mL. MIC values for spoilage bacteria ranged from 0.5 to 5 mg/mL, whereas for spoilage fungi were 0.75 to 10 mg/mL. GC-MS analysis of ethanolic extract identified seven compounds viz. Linoleic acid ethyl ester, (E)-9-Octadecanoic acid ethyl ester, n-Hexadecanoic acid, Dotriacontane, 9,12-Octadecadienoic acid, 2,4-Di-tert-butylphenol and Octadecanoic acid, ethyl ester. Conclusion: The rhizome of Curcuma amada is a rich source of phytochemicals and has an antagonistic effect on food spoilage bacteria and fungi. The chemical constituents present in C. amada rhizome extract indicated antimicrobial potency against spoilage microorganisms that can be utilized in food preservation.