Exhaustive survey on the utilization of Philippine resources revealed urgent need for continued effort on the chemical study of the country’s flora for commercial, industrial and educational purposes. Gumamela is one of the plants that have to be developed for its many uses. Isolation of acid-base indicator from plant is not new in chemistry. Several hundreds of indicators have been
investigated and the list continues to grow. This study investigated on the acidbase indicator properties of gumamela petal varieties.
Three gumamela petal varieties namely: Hibiscus rosa-sinensis var. ‘Gelia Castillo’, Hibiscus rosa-sinensis var. ‘Petite Peach’ and Malvaviscus arboreus var. ‘Penduliflorus’ were used. Testing includes determination of the phytochemical components of the extract and determining indicator properties in acidic and basic solutions.
Results showed different color changes in acid and base solution for all the samples. Supported by phytochemical analysis, the study concluded that thegu mamela varieties tested possessed natural acid-base indicator properties with H. rosa-sinensis var. ‘Gelia Castillo’ having the highest potential. A standard color matrix for each gumamela variety was developed to serve as guide in interpreting its response to acid and base solutions. The color matrix will serve as standard in determining pH of solutions.