C18 luna omega 5 μm polar

To identify the nature of the purple pigment, lyophilized cells of each Rugamonas isolate were homogenized by bead-beating in 1 ml of 95% methanol. The extract (100 μl) was analyzed by Agilent-1200 HPLC. The separation was carried out in a reverse-phase column (C₁₈ Luna Omega 5 μm Polar, 150 by 2.1 mm; Phenomenex) with 35% methanol and 15% acetonitrile in 0.25 M pyridine as solvent A and 50% methanol in acetonitrile as solvent B. Pigments were eluted with a linear gradient of solvent B (10 to 100% in 30 min) at 40°C and at a 0.8 ml/min flow rate. Violacein was detected at 575 nm using an Agilent 1260 diode-array detector, and the purified violacein from Janthinobacterium lividum served as an authentic standard (Sigma-Aldrich).

To identify the nature of the purple pigment, lyophilized cells of each Rugamonas isolate were homogenized by bead-beating in 1 ml of 95% methanol. The extract (100 μl) was analyzed by Agilent-1200 HPLC. The separation was carried out in a reverse-phase column (C₁₈ Luna Omega 5 μm Polar, 150 by 2.1 mm; Phenomenex) with 35% methanol and 15% acetonitrile in 0.25 M pyridine as solvent A and 50% methanol in acetonitrile as solvent B. Pigments were eluted with a linear gradient of solvent B (10 to 100% in 30 min) at 40°C and at a 0.8 ml/min flow rate. Violacein was detected at 575 nm using an Agilent 1260 diode-array detector, and the purified violacein from Janthinobacterium lividum served as an authentic standard (Sigma-Aldrich).