Antimicrobial Evaluation and GC-MS Analysis of Strobilanthes crispus Ethanolic Leaf Extract

Aims: The aim of this study was to assess the potential antimicrobial activities of the ethanolic leaf extract of Strobilanthes crispus (S. crispus) by determining the susceptibilities of various strains of microbes to the extract and to profile the bioactive compounds in the extract using GC-MS.

Study Design: In vitro assays, chromatography and spectrometry analysis.

Place and Duration of Study: This study was carried out at Integrative Medicine Cluster Lab, AMDI, USM and Faculty of Pharmaceutical Sciences, UCSI University, from July 2012 to December 2013.

Methodology: Anti-microbial activity was assessed using disc diffusion on Aspergillus brasiliensis, Candida albicans, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pneumonia. GC-MS analysis was used to profile the bioactive components of the plant part.

Results: The extract exhibited inhibitory activity against Staphylococcus aureus and Streptococcus pneumoniae at 200 mg/ml concentration, whereas no visible inhibition was observed against Aspergillus brasiliensis, Candida albicans, Klebsiella pneumonia, and Pseudomonas aeruginosa. GC-MS analysis of the ethanolic extract revealed the presence of few constituents which include acetic acid, butyrolactone, and hexanedioic acid that have been described in the literature as proven antimicrobial agents.

Conclusion: These results suggest that the ethanolic leaf extract of Strobilanthes crispus (S. crispus) can be used as a nutraceutical against S. aureus and S. pneumoniae.