A Study on Antioxidant Potency and Antibacterial Activity of Water Extracts of Some Spices Widely Consumed in Iranian Diet

The present study was conducted to evaluate the antioxidant and antibacterial activities of water extracts of sumac (Rhus coriaria), barberry (Berberis vulgaris), black pepper (Piper nigrum), red pepper (Capsicum annuum), fennel (Foeniculum vulgare), laurel (Laurus nobilis), cardamom (Elettaria cardamomum), turmeric (Curcuma longa), white mustard (Sinapis alba) and nutmeg (Myristica fragrans). The antioxidant activity of extracts was tested using 2,2-diphenyl-1-picrylhydrazyl and reducing power tests. The antibacterial activity of extracts was determined by agar well diffusion and resazurin microtiter-plate assays. Sumac, laurel and barberry extracts showed the highest antioxidant activity, respectively. Meanwhile, the highest concentration of total phenolic was obtained in the extracts of laurel and sumac. The results of antibacterial tests revealed that the extracts of sumac and barberry had the strongest antibacterial activity against tested bacteria. Practical Applications There is an increasing interest in using plant extracts by the food industry as natural preservatives. Lipid oxidation and microbial growth in food can be controlled by the use of plant extracts. This study showed that the water extracts of sumac, laurel and barberry had the strongest antioxidant activity while the sumac and barberry extracts exhibited the highest antibacterial activity against four foodborne pathogenic bacteria. Therefore, the water extracts of sumac, laurel and barberry can be used as effective preservatives in food systems.