Analysis of total flavonoid content and antibacterial activity of the ethanolic extract of apu-apu herb (Pistia stratiotes) against Salmonella typhimurium

Background: There is a need to develop new anti-infective compounds from natural ingredients that have minimal side effects. Pistia stratiotes (apu-apu) is an example of a natural plant from the Araceae family. Aim: This study aims to determine the total flavonoid content of the ethanolic extract of apu-apu herb and its antibacterial activity against Salmonella typhimurium. Methods: Total flavonoid content was determined by using the AlCl3 method and the antibacterial activity test was done using the disc diffusion method, divided into four test concentrations, namely 100, 200, 300, and 400 mg/mL. Results: The results showed that the total flavonoid content of the ethanolic extract of apu-apu herb was 0.353 ± 0.060 mg QE/g extract. The results of the antibacterial activity test showed that the inhibition zones at concentrations of 100, 200, 300, and 400 mg/mL were 8.2 ± 0.1mm; 9.2±0.15mm; 9.9 ± 0.4 mm, and 11.2 ± 0.25 mm, respectively. Conclusion: It can be concluded that the ethanolic extract of apu-apu herb contains a total flavonoid of 0.353 ± 0.060 mg QE/g and has an antibacterial activity against Salmonella typhimurium.