Assessment of the anti-oxidant, anti-inflammatory and anti-bacterial activities of different types of turmeric (Curcuma longa) powder in Bangladesh

Turmeric (Curcuma longa) powder is one of the most popular spices in Bangladesh and it is widely available under different brands for consumers to choose from. The present study assessed the anti-oxidant, anti-inflammatory, and antibacterial activities of ethanolic extracts of turmeric powder from different forms (home-made, open-market and two commercially packed brands). The home-made and commercially packed (CP I) turmeric (Curcuma longa) powder extracts presented with all the tested phytochemical properties, yet saponin terpenoid and tannins were absent in the commercially packed (CP II) and open-market brands. The home-made turmeric powder had the largest amount (4.53 ± 0.41%) of curcumin compared to the others. Significant anti-oxidant activity was observed in the home-made sample compared to the others (IC50 = 126.78 ± 1.30 and 144.44 ± 3.47 μg/mL for H2O2 and DPPH scavenging activity). Furthermore the home-made turmeric powder exhibited significant (p<0.001) anti-inflammatory properties (IC50 = 114.73 ± 0.41 μg/mL). The most effective antibacterial activity was observed in home-made turmeric powder against Escherichia coli O157: H7 and Staphylococcus aureus NCTC 8325 with zone of inhibition ranged from 17.07 ± 0.27 mm and 17.03 ± 0.30 mm, respectively. Revealed in this study is the significant antioxidant, anti-inflammatory, and antimicrobial properties of all tested turmeric powder (CP I, CP II, open-market and home-made) extracts. The home-made extract showed the best potential. All the tested turmeric powders are good sources of spice for people to consume, but the home-made turmeric powder proved to be the best.