Stability Studies of Garcinia indica by Determination of Anthocyanins

Stability testing is to provide evidence on how the quality of plant products varies with the time under influence of a variety of environmental factors such as temperature and humidity. Hence, kokum juice was subjected to accelerated stability studies and evaluated by anthocyanins content. Anthocyanins are present in the fruit of Garcinia indica, which is responsible for colour of kokum juice. The anthocyanins in juice were studied during six months period by subjecting it to accelerated conditions. The total acidity, brix and pH of the formulation were also monitored as the parameter of stability testing. The study was carried out as per the ICH guidelines.

The method used for total anthocyanins determination involved UV spectroscopy. Measurement of the absorbance was done at 510 nm on sample diluted with pH 1.0 and 4.5 buffers. The pigment content was calculated in absolute quantities with the aid of extinction coefficients. 30 ml of juice was withdrawn from four samples of capacity 200 ml each on 0, 1 and 3 month intervals. The results suggest that an increase in temperature decreases the anthocyanins stability. The degradation of anthocyanins in kokum juice samples was observed which is out of the limits of acceptance criteria according ICH guidelines.