Antibacterial Activity, TLC-Bioautography Analysis, and Determination of Bioactive Components in Ethyl Acetate Extract of Robusta Coffee Leaf (Coffea canephora L.) From Aceh, Indonesia

Abstract

Infectious diseases affect many people in the world, including Indonesia. One of the causes of infection is bacteria, including scherichia coli and Staphylococcus aureus. Robusta coffee (Coffea canephora L.) is one of the plants that is widely encountered on Indonesian plantations. The leaves are usually discarded after being trimmed to maximize the growth of coffee beans. The results of several studies show that robusta coffee leaves demonstrate antibacterial and antioxidant activity due to the presence of flavonoids, alkaloids, tannins, saponins, polyphenols, and chlorogenic acids. The aim of this research to investigate antibacterial activities, total flavonoid content and inspect the phytochemicals of the bioactive compounds as antibacterial with TLC Bioautography in the ethyl acetate extract of robusta coffee leaves. The identification of secondary metabolites was conducted by using the TLC-Bioautography method against Escherichia coli and Staphylococcus aureus. The determination of total flavonoid levels was carried out by using Spectrophotometry UV-Vis. Phytochemical testing showed that the extract contained alkaloids, steroids, phenolics, tannins, and flavonoids. The ethyl acetate extract inhibits the growth of Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 (P=0.00) with 100% extract as the most potent. The results of TLC-Bioautography showed the presence of polyphenolic compounds (Rf 0.36) which was confirmed by a clear zone in the disc diffusion test. The total flavonoid content in robusta coffee leaves was 57.255±0.0348 mg QE/g extract. Ethyl acetate extract from coffee leaves (Coffea canephora L). inhibits the growth of S. aureus and E. coli due to the presence of polyphenolic compounds