2.1. Standards
and
reagents
The Folin–Ciocalteu phenol reagent, gallic acid, chlorogenic
acid
and
3,4-dihydroxybenzoic
acid
were
obtained
from
Sigma
Chemical Co. while the 2,2-diphenyl-l-
picrylhydrazyl (DPPH) was obtained from Alfa Aesar
The
hydrochloric
acid,
sodium
hydroxide,
and
sodium carbonate were obtained from Vetec Química Fina Ltd.