Anthocyanin Content of the Extract of Vitis Vinifera (Autumn Royal Black Seedless Grapes) as pH Indicator / Mariella Louise Gonzales Bengco ; Hannah Gilbreille Simpang Bulaqueña ; Jan Hanzel Timbang Cruz ; Eric MIguel Goyena Del Fuerte ; Janika Daphne Bigayan Gaffuy ; Winalyn Sebastian Fabiano ; Rochel Elaine Cua Lobo ; Brandon Manaloto Mendiola and Roy Jr. Franco Rodiel.

Includes appendices and bibliographical references.

Abstract: The pH indicators are utilized for finding out how acidic or basic a certain chemical is. Specific acids have their specific pH that is less than or equal to 6 while bases are greater than pH 7, and 7 stands for neutral pH. This study was conducted to find out if the anthocyanin content in the Vitis vinifera autumn royal black seedless grapes species can be used for pH indication. The research design used was the experimental study. It was performed to evaluate the potential of the anthocyanin in the Vitis vinifera extract and Vitis vinifera filter paper as pH indicators. From 500grams of autumn royal black seedless grapes prepared, 40 grams of the grape's skin was separated and was subjected to soxhlet extractor for the anthocyanin extraction which used 25 mL ethanol as solvent. The extraction yielded 100 mL anthocyanin extract. Filter paper was soaked in the extract to make the Vitis vinifera extract filter paper. Conducted in 10 trials for each chemical, blue litmus paper, Vitis vinifera extract filter paper and standard pH paper were dipped in hydrochloric acid, acetic, distilled water, ammonia, sodium hydroxide and sodium bicarbonate. Color change was observed upon the experiment. Litmus paper turned pink for acids, purple for neutral and blue for bases. The standard pH paper gave pH1 for hydrochloric acid, pH 3 for acetic acid, pH 7 for distilled water, pH 10 for ammonia, pH 12 for sodium hydroxide and pH 9 for sodium bicarbonate. The Vitis vinifera extract filter paper exhibited change of colors in response of testing the chemicals. It yielded red for hydrochloric acid, pink for acetic acid, purple for distilled water, blue for ammonia, light green for sodium hydroxide and blue for sodium bicarbonate. Since each color was consistently shown in the 10 trials, the Vitis vinifera extract filter paper gave the color range of red-pink-purple-blue-green upon the increasing pH at purple; exact pH determination (quantitative) was not possible.

Thesis - School of Medical Technology