Title | Demonstration of bioprocess factors optimization for enhanced mono-rhamnolipid production by a marine Pseudomonas guguanensis. |
Publication Type | Journal Article |
Year of Publication | 2018 |
Authors | C RDK, R LSundaram, D A, V S, Vasudevan V, Krishnan MElizabeth |
Journal | Int J Biol Macromol |
Volume | 108 |
Pagination | 531-540 |
Date Published | 2018 Mar |
ISSN | 1879-0003 |
Abstract | We identified that Pseudomonas guguanensis produced macromolecular mono-rhamnolipid (1264.52 Da) upon sensing n-hexadecane/diesel/kerosene from its surroundings. Permutation experiments were done to improve the laboratory-scale mono-rhamnolipid production (ie, a three-fold increase) using RSM validation. Consequently, maximal mono-rhamnolipids production [40-50 mg/L] and emulsification abilities [65-70%] were encountered on day 8 using vegetable oil, peptone + yeast extract. EI values for the rhamnolipids were found to be 78±1.75% at 12.5 mg/ mL. Production and secretion of rhamnolipids were accompanied by aggregation of cells at day 6 as pictured in SEM. Pure monorhamnolipids of P. guguanensis was found to lower the surface tension of water to 32.98±0.3 mN/m than the crude and CFSs of P. aeruginosa indicating efficient activity. Utilization and subsequent removal of hexadecane was 77.2% and the breakdown products were fatty acids [decanoic, hexadecanoic, octadecanoic acids and methyl stearates] as signified in Head-space GC-MS. The breakdown products of hexadecane are also present in the synthesized rhamnolipids suggesting their biosynthetic role. Rapid degradation of hexadecane, diesel and kerosene by this emulsifier combined with non-pathogenic trait of P. guguanensis identifies this organism as a viable option to remove n-alkanes from aquatic environments. |
DOI | 10.1016/j.ijbiomac.2017.10.186 |
Alternate Journal | Int. J. Biol. Macromol. |
PubMed ID | 29208557 |
Submitted by kej2006 on June 6, 2018 - 4:13pm