Identification of carotenoid pigments in Bacillus licheniformis isolated from roots of Vitis vinifera

CARLA SALVADORES; ANA C. COHEN; RUBÉN BOTTINI; PATRICIA N. PICCOLI

San Luis

Jornada; XXX Reunión Anual de la Sociedad de Biología de Cuyo; 2012

Sociedad de Biología de Cuyo

Carotenoids are the most widespread naturally occurring yellow, orange and red pigments produced by bacteria, fungi, algae and higher plants. Several species of bacteria accumulate high concentrations of carotenoids. They are of interest due to their antioxidant, UV protecting and natural food colorant properties. In a previous study B. licheniformis was isolated from roots of Vitis vinifera L. (cv. Malbec) and promoted the growth when it was inoculated in Vitis vinifera plants cultivated in vitro (Salomon et al. 2010). The aim of this study was to identify carotenoids produced by B. licheniformis in LB medium. B. licheniformis was cultivated aerobically for 3-10 days at 30 °C and 120 rpm in orbital shaker in dark. Cells were centrifuged at 7000 rpm at 4 °C for 15 min. The upper layer was discarded and residual cells were extracted with different solvents (MeOH, CH3COCH3, MeOH/CH3COCH3 7:3, v/v) overnight at 4 °C. Suspensions were sonicated 10 min and centrifuged. After that, the clear coloured organics phases were transferred into a clear tube. Finally, the carotenoids levels in the supernatant were quantified through absorbance between 300-600 nm. The best solvent was MeOH/CH3COCH3 and production increased from 3 to 10 days of culture with B. licheniformis. The highest peak was found at 474 nm corresponding to lycopene.