INTERNATIONAL JOURNAL OF AGRICULTURAL TECHNOLOGY

Volume 14, No. 05, Month SEPTEMBER, Year 2018, Pages 783 - 796

Bioactivity screening of thai spice extracts for applying as natural food preservatives

Wanangkarn, A., Tan, F. J., Fongsawad, K. and Tirasaros, M.

Abstract Download PDF

Herbs and spices have been used to enhance the flavour and aroma in Thai food for thousands of years and are also considered as a medicinal plant. This study was to investigate the antioxidant and antimicrobial activities of selected Thai spices (sweet basil, holy basil, finger root, kaffir lime leaf, black pepper, galangal, and lemongrass), using different extraction solvents, including aqueous and ethanol. The results of antimicrobial activity against four foodborne pathogens (Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus, and Listeria monocytogenes), using agar disc diffusion and broth dilution assays, showed that the galangal ethanol extracts had the highest antimicrobial activity with the minimum inhibitory concentration and minimum bactericidal concentration of 12.5 and 50 mg/ml, respectively. In antioxidant activity, the sweet basil ethanol extracts showed the highest antioxidant activity in terms of total phenolic content (2.65 mg GAE/g), DPPH radical scavenging (90.30%) and thiobarbituric acid reactive substances. This study has demonstrated that galangal and sweet basil extracts could be used as natural antioxidant and antibacterial agents in food preservation with low side effects and could also promote human health.

Keywords

Thai spice extracts, solvent extraction, antimicrobial activity, antioxidant activity

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