title: Isolation of rhamnolipids-producing cultures from faeces: Influence of interspecies communication on the yield of rhamnolipid congeners.
abstract: The aim of this study was to evaluate the ability of bacterial cultures isolated from cattle, poultry or pig faeces and manure to produce rhamnolipids, as well as to investigate the influence of interspecies communication on possible quantitative differences in the production of rhamnolipid congeners. Initial screening methods (oil spreading, drop collapse, haemolytic activity and emulsification activity) showed that approximately 36% of the 51 isolated cultures exhibited the ability to produce biosurfactants. Subsequent studies using a selected culturable mixed culture (which included Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli) revealed that only P. aeruginosa was able to produce this biosurfactant. HPLC-MS analysis showed that the surface active compounds were rhamnolipids. Further comparative studies confirmed that the total yield of rhamnolipids was notably higher in the bioreactor inoculated with the selected mixed culture (940.58±1.10mg/L) compared to the bioreactor inoculated with the axenic strain of P. aeruginosa (108.47±0.41mg/L). Twelve rhamnolipid congeners were identified during cultivation of the selected mixed culture, whereas six congeners were detected during cultivation of the sole axenic strain of P. aeruginosa. Furthermore, increased production of rhamnolipids was observed when the concentration of autoinducer molecules (AI-2) responsible for interspecies signaling increased, suggesting the influence of quorum-sensing communication on biosynthesis efficiency. This observation may be of importance for large-scale production of this biosurfactant, as it opens new possible solutions based on the use of mixed cultures or external addition of stimulating autoinducers.
authors.affiliation: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland. Electronic address: marta.w.wozniak@doctorate.put.poznan.pl.
authors.forename: Marta
authors.initials: M
authors.lastname: Woźniak-Karczewska
authors.affiliation: Department of Biotechnology and Food Microbiology, University of Life Sciences in Poznań, Wojska Polskiego 48, 60-627 Poznań, Poland.
authors.forename: Kamila
authors.initials: K
authors.lastname: Myszka
authors.affiliation: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Sznajdrowska
authors.affiliation: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors.forename: Alicja
authors.initials: A
authors.lastname: Szulc
authors.affiliation: Institute of Chemistry and Technical Electrochemistry, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Zgoła-Grześkowiak
authors.affiliation: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Ławniczak
authors.affiliation: Institute for Ecopreneurship, School of Life Sciences, University of Applied Sciences and Arts Northwestern Switzerland, Gründenstrasse 40, 4132 Muttenz, Switzerland.
authors.forename: Philippe F-X
authors.initials: PF
authors.lastname: Corvini
authors.affiliation: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Chrzanowski
mesh_terms: D000818:Animals; D001709:Biotechnology; D002417:Cattle / Q000382:microbiology; D002645:Chickens / Q000382:microbiology; D013293:Enterococcus faecalis / Q000302:isolation & purification / Q000378:metabolism; D004926:Escherichia coli / Q000302:isolation & purification / Q000378:metabolism; D005243:Feces / Q000382:microbiology*; D006017:Glycolipids / Q000096:biosynthesis*; D006714:Homoserine / Q000031:analogs & derivatives / Q000378:metabolism; D007783:Lactones / Q000378:metabolism; D008372:Manure / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification / Q000378:metabolism; D053038:Quorum Sensing; D013501:Surface-Active Agents / Q000378:metabolism; D034421:Sus scrofa / Q000382:microbiology
chemical_list: D006017:Glycolipids; D007783:Lactones; D008372:Manure; C091088:N-octanoylhomoserine lactone; D013501:Surface-Active Agents; C418382:rhamnolipid; C085113:Pseudomonas aeruginosa autoinducer; D006714:Homoserine
keywords: Biosurfactant; Mixed culture; Pseudomonas aeruginosa; Quorum sensing; Rhamnolipids