Effect of Rhamnolipids on the Dissolution, Bioavailability, and Biodegradation of Phenanthrene

Rhamnolipid Biosurfactants Produced by Pseudomonas Species

“…The Exxon Valdez oil spill is a well-known example of biosurfactant use in bioremediation (Harvey 1990). Zhang and Miller (1997) 4% of oil and demonstrated that with the addition of rhamnolipids, C8-C11, C12-C21, C22-C31, and C32-C40 alkanes were degraded by 100%, 83-98%, 80-85%, and 57-73%, respectively, after 56 days. Several studies reported that rhamnolipids are efficient in the removal/cleanup of heavy metals due to interactions between their polar glycosidic groups and metal ions.…”

“…Daziel et al (1996) demonstrated in their study that rhamnolipid production is responsible for an increase in the aqueous solubility of naphthalene. Zhang et al (1997) investigated the effect of two forms of rhamnolipids on the dissolution and bioavailability of phenanthrene and found monorhamnolipid was more effective than dirhamnolipid for solubilization but phenanthrene within monorhamnolipid micelles was less bioavailable than phenanthrene within dirhamnolipid micelles. So they indicated that the effect of a surfactant on biodegradation is a combination of the solubilizing power of the surfactant and the bioavailability of the substrate within the surfactant micelles.…”

Development of an In Situ Biosurfactant Production Technology for Enhanced Oil Recovery

“…Biosurfactant production has traditionally been viewed as a mechanism to enhance hydrocarbon biodegradation by increasing the apparent aqueous solubility of the hydrocarbon [52][53][54][55][56][57][58][59][60][61] or by enhancing the interaction of the microbial cell with the hydrocarbon [60,62,63]. By dispersing or increasing the apparent solubility of poorly soluble hydrocarbons, especially polynuclear aromatic compounds, these compounds become more bioavailable and, thus, more amenable to biodegradation [57,61,[64][65][66].…”

“…The absorbance was measured at 660 nm after 10 min. The concentration of sulfide was calculated from a sulfide standard curve ranging from 0 to 50 mg/L of sulfide (53).…”

Exopolymeric substances (EPS) produced by petroleum microbial consortia

“…7,8 Biosurfactants with proven potential for bioremediation include rhamnolipids produced by Pseudomonas aeruginosa and surfactins from Bacillus subtilis. 9 The role of biosurfactants on hydrocarbon microbial degradation has been investigated on pure compounds such as tetradecane, hexadecane, 10 octadecane, 5 phenanthrene 3,11 Exopolymeric Substances (EPS) Produced by Petroleum Microbial Consortia J. Braz. Chem.…”