2.2. Ascorbic acid determination
Vitamin C was estimated by the method described in AOAC
(1984). 1.0 g freeze dried powder was macerated with 10 ml of
0.4% oxalic acid in water and centrifuged at 8,000 rpm. The
500 ll and 1000 ll aliquots of the supernatant in triplicate were
maintained to 3.0 ml by 0.4% oxalic acid followed by the addition
7.0 ml of 2,6-dichlorophenol indophenol dye solution. The test
mixture was properly mixed and its absorbance was recorded
immediately at kmax 518 nm in UV-Varian Cary 50 spectrophotometer. The amount of Vitamin C was calculated by comparison
with standard curve and expressed as mg/100 g.