2.4.2. DPPH radical scavenging activity
Antioxidant activities of the white tea extracts (WTE) were estimated by measuring their scavenging capacity against the DPPH radical Tea extract (20 ll) was added to 120 ll of a 0.004% MeOH solution of DPPH. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) was used as standard. Absorbance at 517 nm was determined after 30 min incubation
in dark at room temperature, and the percentage of inhibitionwas calculated as [(A0 – A1)/A0] _ 100, where A0 is the absorbance of the control (dH2O), and A1 is the absorbance of the samples. A graph of the DPPH radical scavenged (%) vs. concentration of sample was plotted. The IC50 value denotes the effective concentration of sample used to reduce 50% of available DPPH radicals. In the DPPH radical scavenging assay, the deep violet colour of DPPH is reduced to a light yellow colour due to the abstraction of hydrogen atoms from the antioxidant compound
2.4.2. DPPH radical scavenging activity
Antioxidant activities of the white tea extracts (WTE) were estimated by measuring their scavenging capacity against the DPPH radical Tea extract (20 ll) was added to 120 ll of a 0.004% MeOH solution of DPPH. Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) was used as standard. Absorbance at 517 nm was determined after 30 min incubation
in dark at room temperature, and the percentage of inhibitionwas calculated as [(A0 – A1)/A0] _ 100, where A0 is the absorbance of the control (dH2O), and A1 is the absorbance of the samples. A graph of the DPPH radical scavenged (%) vs. concentration of sample was plotted. The IC50 value denotes the effective concentration of sample used to reduce 50% of available DPPH radicals. In the DPPH radical scavenging assay, the deep violet colour of DPPH is reduced to a light yellow colour due to the abstraction of hydrogen atoms from the antioxidant compound
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