Pustaka Ilmiah Universitas Padjadjaran

Proceeding Biotech

Study Of Antimicrobial Activity From Guava (Psidium Guajava L.) Leaf Extract Towards Pathogenic Microbes

Guava leaves have been utilized traditionally as medicine and known as an antimicrobial agent as well. In this research, guava leaves were extracted using maceration method. The solvents used in this research were water, ethyl acetate, and hexane. Guava leaves extracts were tested towards Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Penicillium sp. by the agar diffusion method. The objectives of this research were to (1) determine the MIC and MBC of guava leaves extracts towards tested microbes, (2) determine the active compound in guava leaves extract, (3) observe the influence of certain pH, sugar concentration, salt concentration, and heat treatment on the antimicrobial activity of guava leaves extract. The result showed that ethyl acetate extract could inhibit all the tested bacteria excluding Penicillium sp. The MIC and MBC for Escherichia coli, Staphylococcus aureus, and Bacillus cereuswas0.017% and 0.067%, 1.177% and 4.707%,0.126% and 0.504%, respectively. The active compounds found in guava leaves were alkaloid, saponin, tannin, phenol, flavonoid, triterpenoid, and steroid. The results indicate ethyl acetate extract was influenced by pH and effective at pH 4. Sugar addition could increase the antimicrobial activity. Furthermore, low concentration of salt could decrease the antimicrobial activity towards B. cereus as well as that by heat. Moreover, the results also indicate ethyl acetate extract could inhibit the growth of B. cereus spores.