ISOLATION OF CATECHINS FROM WHITE TEA (CAMELLIA SINENSIS) AND ANTIOXIDANT ACTIVITY TESTING WITH DPPH METHOD

• Main Author: NAELULMUNA (NIM:10514059), NURLAELI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/29804
• Institution: Institut Teknologi Bandung

Tea is one popular drink that is often consumed by the world community, including Indonesia. <br /> <br /> One type of tea that has high antioxidant content is white tea. White tea is a tea with the simplest <br /> <br /> processing process, namely through the forering and drying. So white tea contains more <br /> <br /> polyphenol compounds in the form of catechins and derivatives than other types of tea. In this <br /> <br /> study the isolation of white tea was carried out with liquid-liquid extraction method then <br /> <br /> purification using gravity column chromatography with polyamide stationary phase. The results <br /> <br /> of TLC crude extract using eluent ethyl acetate: water: formic acid (90:5:5) there were three <br /> <br /> stains (Rf1 = 0,286; Rf2 = 0,514; Rf3 = 0,629) while the results of TLC after purification <br /> <br /> contained two stains (Rf1 = 0.571 and Rf2 = 0.657) and successfully separates caffeine <br /> <br /> compounds. Then the analysis of compounds using High Performance Liquid Chromatography <br /> <br /> (HPLC) was carried out to determine the number of components and a rough description of the <br /> <br /> type of catechins used in white tea. The results of HPLC showed the presence of catechin <br /> <br /> derivatives in the form of epicatechin (EK), epicatechin gallate (EKG), and the largest <br /> <br /> component was epigalocatechin gallate (EGKG). After that, further structural analysis was <br /> <br /> carried out using an infrared spectrum which showed the absorption around 3390 cm-1 which <br /> <br /> showed the absorption of the -OH group. Uptake at wave number 1693 cm-1 indicates the <br /> <br /> vibration of conjugated C = O, and the vibration of C-O-C in the ester in the form of acetate at a <br /> <br /> wave number of 1238 cm-1. Confirmation of catechin derivatives that were isolated was analyzed <br /> <br /> using 1H-NMR and 13C-NMR. Testing of antioxidant activity was carried out using DPPH (2,2- <br /> <br /> diphenyl-1-pikrilhidrazil) method. Antioxidant properties before purification have weaker <br /> <br /> antioxidant activity than after purification. The acquisition of IC50 value of white tea extract after <br /> <br /> purification was 39,87 &#956;g / mL and ascorbic acid as a comparison was 28,36 &#956;g / mL which <br /> <br /> belonged to a very strong antioxidant category, while the IC50 value of white tea extract before <br /> <br /> purification was 56,95 &#956;g / mL and is a strong antioxidant category.