Marihysin B, a new cyclic lipopeptide from culture broth of Staphylococcus sp.- antimicrobial and glucoamylase inhibitory activities

A new cyclic lipopeptide, marihysin B (1) and the well-known marihysin A (2) were isolated from Staphylococcus sp. culture broth obtained from Corallina officinalis L. Extensive 1D (1H and 13C) and 2D (1H-1H COSY, HSQC, HMBC, and NOESY) NMR spectral investigations were used to determine the structures of isolated compounds. With inhibition zone widths of 11 to 25 mm and MICs of 25 mu g/mL, compounds 1 and 2 showed marked antifungal activity against Aspergillus niger, Penicillum crustosum, Trichophyton concentricum, and Schizophyllum commune compared to nystatin (inhibition zone diameters 23-31 mm). Additionally, computational study was done to determine the possible mechanism underlying the antifungal activity of the two cyclic lipopeptides against Schizophyllum commune glucoamylase. These substances showed similar binding affinities to the target's reference compound.