Isolation and screening for antimicrobial activity of bacteria from sediments in Sitio Kay Reyna, Barangay Lumanyag, Lian, Batangas

• Main Author: Marcelino, Dennis N.
• Format: text
• Language: English
• Published: Animo Repository 1996
• Subjects: Microbial sensitivity tests; Bacterial growth; Marine sediments > Batangas
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/1372
• Institution: De La Salle University

A total of eighty bacterial colonies were isolated from soil collected from Sitio Kay Reyna, Barangay Lumanyag, Lian, Batangas. The bacterial isolates were screened for antimicrobial activity on three gram negative pathogens, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi a gram positive, Staphylococcus aureus and a fungus, Candida albicans.Bacterial isolates, DM3, DM5, DM6, DM7, DM9, DM11, DM13, DM14, DM16, DM20, DM21, DM24, DM25, DM27, DM30, DM31, DM40, DM43, DM55 and DM72 showed inhibitory activity against some of the test organisms. Seven of the isolates (DM5, DM7, DM13, DM14, DM16, DM55 and DM72) were positive against Candida albicans four (DM5, DM7, DM13 and DM14) were positive against Salmonella typhi, two (DM5 and DM7) against Pseudomonas aeruginosa, and eighteen (all isolates except DM55 and DM72) against Staphylococcus aureus. None of the bacterial isolates inhibited Escherichia coli. Relative to this experiment, isolates DM5 and DM7 were the most active, inhibiting four of the five test organims.The general morphological characteristics of the soil isolates were irregular in form, flat elevation, smooth colony formation with undulate margins and translucent density. Most of the isolated bacteria were gram negative rods.