Phytochemical and antimicrobial investigation and comparison between young and mature Psidium guajava leaves extract

Ethnomedicinal properties of Psidium guajava L., or also known as guava leaves has been known since years ago. Nowadays, a lot of guava leaves-based products emerge in industries such as tea and cosmetic. The aims of this study are to examine and compare the variation in the phytochemical constituent as well as the antimicrobial efficacy of young and mature leaves extract. Phytochemical analysis shows the presence of phenol, tannin, terpene, saponin, and flavonoid in the mature leaves methanolic extract. A similar result was obtained in the young leaves extract but no saponin was detected. Total phenols content in young and mature leaves were determined at a total of 31.2 mg and 162 mg GA/g. Both leave extract was carried out to determine the antimicrobial properties by tested against two Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and one gram-negative bacteria (Salmonella enterica) through the disk-diffusion method by employing 40 µL of leaf extract solution per disk. Based on the observation, both young and mature extracts exhibited inhibitory activity (