Related Experiment Video
Updated: Jul 11, 2026

Quantification of Violacein in Chromobacterium violaceum and Its Inhibition by Bioactive Compounds
Published on: August 8, 2025
Antibacterial and antiviral naphthazarins from Maharanga bicolor
M Rajbhandari1, T H Schoepke, R Mentel
1Research Center for Applied Science and Technology, Tribhuvan University, Kathmandu, Nepal.
Abstract:
Maharanga bicolor, Boraginaceae, is used in the Nepalese ethnomedicine for the treatment of several diseases. In the course of screening investigations the dichloromethane extract of the roots of Maharanga bicolor was found to inhibit the growth of gram positive bacteria. Bio-assay directed fractionation led to the isolation of five active naphthazarins, deoxyalkannin (1), alkannin (2), acetylalkannin (3), alkannin beta-hydroxyisovalerate (4) and alkannin beta-acetoxyisovalerate (5). Compounds 2-5 showed antibacterial activity against multi resistant human pathogenic Staphylococcus and Enterococcus species and 1, 4 and 5 showed antiviral activity against herpes simplex virus type-1.
Related Concept Videos
Antiprotozoal Agents
Anthelminthic Agents
Antiviral Nucleoside Inhibitors
Antifungal Agents
Antimicrobial Effectiveness

