Lipid storage compounds in raw activated sludge microorganisms for biofuels and oleochemicals production

Lipid accumulation by Rhodococcus rhodochrous grown on glucose

“…Lipids were extracted from a freeze-dried pellet using a modified Bligh and Dyer [3] method as described by Revellame et al [27]. The extract was filtered through glass wool into a tared amber vial.…”

“…The composition of the lipid extract from fermenter samples was evaluated using thin-layer chromatography (TLC) as described previously [27]. The dried lipid extracts were reconstituted in 1 mL chloroform and applied to a 20 × 20-cm glass-backed Analtech Uniplate™ pre-coated with 250-mm silica gel-G (Sigma-Aldrich, St. Louis, MO, USA).…”

Effect of pH on biodiesel production and the microbial structure of glucose-fed activated sludge

“…The ratio increased from 14% to 55% and 58% after cultivation with and without pH control, respectively. Revellame et al (2012) proved that the lipids extracted by a modified Bligh & Dyer extraction procedure from raw activated sludge are complex. The major compounds in the lipid extracts were polyhydroxyalkanoates (PHAs), wax esters (WEs), steryl esters (SEs), triacylglycerides (TGs), free fatty acids, free sterols and phospholipids (PLs).…”

“…The biodiesel yield of raw activated sludge from WWTPs is generally low, with approximately 20 mg g À1 of dry sludge (Mondala et al, 2009;Revellame et al, 2012). It is necessary to increase the lipid content and biodiesel yield to make it more competitive.…”

Energy from Waste Materials and Unconventional Sources

“…Activated sludge or secondary contains a microbial population responsible for the biological treatment of wastewater. This population mostly consists of heterothrophic bacteria which utilize the organic content of the wastewater for growth, either as part of their cellular structures or as energy and carbon storage compounds which are mostly lipidic in nature (Revellame et al 2012). The primary sludge is a combination of floating grease and solids.…”