A comparative study of the antioxidant scavenging activity of green tea, black tea and coffee extracts: A kinetic approach

作者：Anissi Jaouad; El Hassouni Mohammed; Ouardaoui Abdelkrim; Sendide Khalid^*

来源：Food Chemistry, 2014, 150: 438-447.

DOI：10.1016/j.foodchem.2013.11.009

• DPPFI* free-radical
• Kinetic behavior
• Second-order model
• Green tea
• Black tea
• Coffee
• DPPFI* scavenging efficiency comparison

The antioxidant activities of three beverages, coffee, black tea and green tea, along with their major components, were investigated in terms of their reaction with the stable radical 2,2'-dipheny1-2-picrylhydrazyl (DPPI-1(.)). We used a kinetic approach in parallel with quantification methods based on a fixed end-point to determine the scavenging efficiency of compounds abundant in these beverages during their reaction with DPPH. using a stopped-flow spectrophotometer-based method. Ascorbic acid, (+)-catechin, (-)-epigallocatechin, tannic acid, and caffeic acid were selected as model antioxidants to study in coffee, black tea and green tea. We applied a second-order model to demonstrate similarities in the kinetics behavior of beverages and related compounds. Our findings showed the slopes K-2'((mol/L)(-1) s(-1)) and K-max ((mol/L)(-1) s(-1)) exhibited similar and correlated values; we suggest the variation in k(2)' as a function of time is more informative about antioxidant properties than reaction with DPPH. alone. We also used IC100 to test the reliability of the relative

• 出版日期2014-5-1