THE STUDY ON ALCOHOLIC EXTRACT OF Tagetes erectus, Bougainvillea glabra & Caesalpinia pulcherrima - As pH Herbal Indicator

A pH indicator is weak acid and halo chromic chemical compound that is added in small quantity to a solution so that the pH (acidity or basicity) of the solution can be determined visually during experiment. Almost all indicators used for acid-base titrations are synthetic compounds, slightly expensive and are unavailable so attempt is made to prepare natural indicator by using different flower extracts. These flowers are very common and easily available; hence indicator obtained from them will be cheap & economical. Every indicator are exhibits a different range of colors at different pH values. This study has been done to investigate the indicator properties of alcoholic extract of flower- Tagetes erectus, Bougainvillea glabra & Caesalpinia pulcherrima. All sample’s Pigments were extracted & evaluated by preparing different pH strips by socking method. Their acid-base titration readings were compared with that of already existing synthetic indicators phenolphthalein and the work proved to be acceptable in introducing flower pigments as a substitute to the synthetic indicator in the acid-based indicators.