Kumari Smita


Objective: The present investigation was designed to study the inhibitory effects of methanolic leaf extract of Ocimum canum (O. canum) on α-glucosidase using in vitro model followed by an assessment of bioactive compounds.

Methods: The methanolic leaf extract was prepared by Soxhlet extraction method and partially purified by thin layer chromatography (TLC). Each band was subjected to α-glucosidase inhibition study. The positive bands were further characterized by high-performance liquid chromatography (HPLC) and quadrupole time of flight (Q-TOF) micro mass spectrometer.

Results: Out of the several combinations of solvent systems, toluene, ethyl acetate and formic acid combination in the ratio of 7:2:1 revealed 5 bands on the TLC sheet. Among all the TLC bands, 2 bands (band A and B) showed the significant inhibitory effect on α-glucosidase activity. HPLC analysis of band A and B revealed the presence of two important polyphenolic compounds, namely rosmarinic acid (RA) and ursolic acid (UA). Q-TOF micromass spectrometer analysis revealed the percentage availability of RA, caffeic acid, tartaric acid, quercetin and other polyphenolic components in the bioactive bands.

Conclusion: The study revealed that methanolic leaf extract of O. canum exhibits potent inhibition of α-glucosidase activity. Inhibition of α-glucosidase activity might be attributed to the presence of the polyphenolic compounds like RA and UA. Therefore, this finding can lead to the development of natural α-glucosidase inhibitors by the O. canum leaf extract.


Ocimum canum, α-glucosidase, Hyperglycemia, Rosmarinic acid, and Ursolic acid

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Ocimum canum, α-glucosidase, Hyperglycemia, Rosmarinic acid, and Ursolic acid





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International Journal of Pharmacy and Pharmaceutical Sciences
Vol 10, Issue 1, 2018 Page: 126-131

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Kumari Smita
Department of Microbiology and Biotechnology, Bangalore University, Bangalore-560056, India

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