Study of Acid-base Indicator Property of Ethanolic Extract of Nerium indicum Flower

A study has been done to investigate the indicator property of ethanolic extract of Nerium indicum. The commonly used synthetics indicators cause environmental pollution and pose hazardous effects in human body. Natural pigments in plants are highly coloured substance and may change with pH variation. The equivalence points of the titrations using flower extract is almost close or coincide with that of phenolphthalein (synthetic indicator). Therefore, use of ethanolic extract of Nerium indicum as an indicator for acid-base titration could be effectively employed as a substitute to the synthetic acid-base indicators.