Jebakumar Solomon, R.D., Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu 625 021, India
Satheeja Santhi, V., Department of Molecular Microbiology, School of Biotechnology, Madurai Kamaraj University, Madurai, Tamil Nadu 625 021, India

Herbal extracts play an essential role in treating various diseases. The threats in drug resistant pathogenic microbial strains can be prevented by the un-tapped medicinal principles from plants. The present study has been focused to search for powerful antimicrobial natural products from Dictyota acutiloba J. Ag. against human enteric pathogens and dermatophytic fungi. Chloroform and acetone extracts of Dictyota acutiloba exhibited antimicrobial activity against methicillin resistant Staphylococcus aureus (MRSA), methicillin susceptible Staphylococcus aureus (MSSA), Enterobacter sp., Pseudomonas aeruginosa MTCC741, Salmonella typhi MTCC733, Bacillus subtilis, Klebsiella pneumoniae MTCC109, Candida albicans and Aspergillus niger MTCC281. Purified compounds A1 and C1 by column chromatography, TLC and HPLC inhibited the gram positive, gram negative bacteria and fungi. MIC of C1 and A 1 ranged between 0.5 and 0.9 μg ml-1. The absorption maximum of C1 and A1 was 355 nm. Structural characterization of these purified molecules can lead to the new therapeutic molecule to fight the pathogenic microorganisms. © 2008 Springer Science+Business Media B.V.