Antimicrobial investigation of Annona muricata (soursop) leaves against bacteria causing skin infection / Sarah Afiqah Yahaya

SSTI is the skin infection caused by pathogenic bacteria that infect skin layers and underlying soft tissues. This study is done to identify the phytochemical substance in extract and fraction of A. muricata leaves and to determine the antimicrobial activity of the leaves. A. muricata leaves was extracted by using cold maceration technique with three different polarity of solvent which are methanol, ethyl acetate and hexane. The test on phytochemical screening was done to determine the presence of alkaloid, flavonoid, tannin, saponin and phenol in A. muricata leaves extract. The antibacterial activity of crude extract was tested against four
pathogenic bacteria which are Escherichia coli, Staphylococcus aureus, Salmonella typhi and Pseudomonas aeruginosa by using disc diffusion method. Finally, A. muricata methanol extract shows the best antibacterial against all four pathogenic bacteria was tested by using MIC method. Methanol extract have the highest percentage yield extraction with 3.01 % compared to ethyl acetate and hexane extract. Phytochemical analysis, methanol extract showed the presence of alkaloid and flavonoid. Meanwhile, ethyl acetate extract showed the presence of tannin, saponin and phenolic while, hexane showed a presence of tannin and phenolic. Methanol extract is the most effective against E. coli. Lastly, MIC test of methanol extracts showed that methanol extract exhibit minimum inhibition concentration in inhibiting E. coli with MIC value of 75 mg/ml. As a conclusion, this study showed that A. muricata contains several important phytochemicals and has a great potential as active antibacterial agents. Further study regarding methanol extracts of A.muricata leaves is recommended to determine the identity of the antibacterial compound from the leaves of A.muricata and also to determine their full spectrum of efficacy.