ISOLATION OF ANTHOCYANIN FROM MANGOSTEEN FRUIT (Garcinia Mangostana L.) PERICARP AND ITS APPLICATION AS CHEMOSENSORS; ISOLASI ANTOSIANIN DARI KULIT BUAH MANGGIS (Garcinia Mangostana L.) DAN APLIKASINYA SEBAGAI CHEMOSENSOR

Asokawaty, Reny Violeta, Bambang Purwono

2015 | Skripsi | FMIPA

Isolation of anthocyanin from mangosteen pericarp (Garcinia Mangostana L.) has been investigated. The extract was identified and found contained of anthocyanin, which can be used as natural indicator of acid-base titration. Anthocyanin was extracted using maceration method with ethanol 97%. The isolate was identified using Thin Layer Chromatography (TLC) and UV-Vis spectrophotometer. To be applied as indicator for titration and anion sensor, the colour changes occurred in anthocyanin extract was observed as the effect of pH and various anions such as F-, Cl-, Br-, I-, CN-, SO4 2-, and CO3 2-. The extract was also applied in several bases of ammonia, sodium sulfate, triethylammine, and spoiled fish. Anthocyanin was obtained from mangosteen pericarp as reddish brown liquid extract. It was eluted in acetonitrile: trifuoroacetic acid (TFA) mixture (9.9: 0.1) and found as 3 spots. Based on UV-Vis analysis, it gave maximum wavelength at 280 and 530 nm. This indicated the major and minor anthocyanin pigment of cyanidin-3-sophoroshide and cyanidin-3-glucoside, respectively. The total anthocyanin content (TAC) 48.56 mg/100 g fresh pericarp was obtained. The extract gave yellow colour in acidic condition and clear light brown in basic medium as the function of pH. The extract colour was turned out into light brown in the presence of fluoride, cyanide, and carbonate. As its application in the detection for food deterioration, the colour of the extract was changed from reddish brown into dark brown with addition of sodium sulfate, ammonia, triethylamine, and spoiled fish. Therefore, anthocyanin extract from mangosteen pericarp could be applied as chemosensors of indicator especially in weak acidstrong base titration with pH range 9-10, selective anion sensor for fluoride, cyanide and carbonate ion, and indicator for food deterioration containing of ammonia, sulfate, triethylamine and histamine in spoiled fish.

Kata Kunci : chemosensor; anthocyanin; mangosteen pericarp