The Acceptability of Bignay (Antidesma Bunius) Fruit Extract as an Organic-Based pH Indicator

Nowadays, experts are actively seeking ways to become more eco-friendly in response to the pressing environmental challenges. Similarly, educational institutions are encouraged to implement sustainable practices by promoting the use of environmentally safe materials in scientific activities. The goal of this study was to assess the acceptability of Bignay pH indicator as an alternative to synthetic pH indicators in school laboratories. To achieve this, the study employed an Explanatory Sequential Research Design, which combines both Experimental and Descriptive approaches. To obtain the necessary data, the researchers conducted controlled experiments, in-depth interviews with Professional Chemistry Teachers using structured survey questionnaires along with live demonstrations, and the product underwent a phytochemical laboratory test by DOST. Upon analyzing the results, it was revealed that Bignay extract showed potential as a natural pH indicator. This claim was strengthened by the DOST phytochemical test; the test report revealed that Bignay fruit extract pH indicator contained significant constituents such as Sterols, Triterpenes, Flavonoids, Alkaloids, Glycosides, and Tannins, which were known to have color-changing properties in response to varying pH levels. Hence, the extract proved to be suitable for use as a natural pH indicator. Moreover, the acceptability phase garnered a mean of >3.50 for parameters such as Color, Odor, and Accuracy, which unveiled that the Bignay pH indicator was an acceptable alternative to synthetic indicators used in schools its sharp color transitions ranging from pink, green, blue, and yellow, its subtle odor, and its accuracy in determining the pH level of substances. In addition, the shelf life extended up to sixty (60) days making it appropriate for use in laboratory activities. To obtain more accurate results, the researchers recommend the use of fully ripened (violet-colored) Bignay (Antidesma bunius) fruits.

Bignay, Acceptability, pH indicator, Phytochemical, Shelf life

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