PHYTOCHEMICAL, ANTIMICROBIAL, ANTIOXIDANT, AND CATECHIN ANALYSIS OF GREEN TEA (Camellia sinensis var assamica) FROM NORTH SUMATERA, INDONESIA.

The taste of green tea is different and unique; factors that contribute to this include the type of picking method, leaf age, variety, and clones. The researchers used the disc method for antimicrobial testing, the DPPH method for antioxidant testing with a visible spectrophotometer set to 515 nm wavelength, the HPLC method for catechin content analysis, and phytochemical screening as a qualitative test. The results of this study's phytochemical screening tests revealed that green tea was positive for terpenoids with Liebermann Bouchard reagent, flavonoids, and tannins with FeCl3 reagent, and good inhibition zones for pathogenic bacteria of Staphylococcus aureus, Streptococcus mutans, and Salmonella typhi. The outcomes of the negative control, 5%, 10%, and 15% green tea ethanol extract against the following microorganisms were: 0; 4,3; 6,35; 8,05 mm for Staphylococcus aureus, 0; 5,9; 6,95; 8,55 mm for Streptococcus mutans, and 0; 3,45; 4,4; 6,45 mm for Salmonella typhi. Results indicated that Salmonella typhi and Staphylococcus aureus were more effectively inhibited by green tea ethanol extract than Streptococcus mutans. Antioxidants demonstrated IC50 of 33.33 indicating a very significant antioxidant activity in the test. determined using a visible spectrophotometer. The HPLC test yielded a catechin content of 16.9%. [ABSTRACT FROM AUTHOR]