Effects of extraction methods on the phenolic, flavonoid and antioxidant compounds of selected medicinal-aromatic spices: a comparative study

Spices are important gastronomic ingredients utilized globally to increase the flavor of foods. This study aimed to compare the quality characteristics and effects of classic extraction (CE) and ultrasound-assisted extraction (UAE) on the bioactivity of 10 selected medicinal aromatic spices (mint, thyme, black pepper, cumin, clove, green cardamom, turmeric, ginger, cinnamon and sumac) frequently used in world cuisines. The analyses revealed that the spices were good sources of protein (4.71-19.68%) and ash (6.45-15.53%). The L*, a*, b*, H degrees, C*, browning index (BI), whiteness index (WI) and yellowness index (YI) values of the spice samples ranged from 24.70 to 71.36, -1.33 to 18.55, 1.76-59.22, 23.79-95.23, 4.37-62.06, 19.40-214.77, 24.55-63.09 and 10.06-137.89, respectively. Generally, the difference in the antioxidant capacity between the CE and UAE methods was statistically significant (P<0.05). UAE treatment significantly decreased the extraction time of bioactive compounds from spices. The total phenolic content (TPC), total flavonoid content (TFC), DPPH center dot, CUPRAC and FRAP values of the spices ranged from 7.96 to 145.98 mg GAE/g, 7.85-271.36 mg QE/g, 1.57-172.94 mg TE/g, 9.57-744.27 mg TE/g and 1.50-423.53 mg TE/g, respectively. With both extraction methods, the highest antioxidant capacity was detected in clove, whereas the lowest was detected in green cardamom. Principal component analysis (PCA) indicated that cloves had the most distinct and strong antioxidant capacity, followed by cinnamon and sumac. In conclusion, we believe that this research contributes to both the importance of selected spices in nutrition and gastronomy and the role of the extraction technique in optimizing the health-promoting potential of spices for food and nutraceutical applications. [GRAPHICS] .