Characterisation of a novel “glyco-organochlorine” bioflocculant produced from Pseudomonas aeruginosa strain F29 isolated from pig fecal matter collected from a mixed animal farm in Ibadan, Oyo State, Nigeria

Abstract

Antibiotic resistance has reached global proportions, and the discovery of effective alternatives to the common antibiotics currently in use, could aid in solving this problem. The aim of this study was to characterise a bioflocculant produced from Pseudomonas aeruginosa strain F29, accession number OQ734844, with 69% flocculating activity and which had been observed to possess biocontrol activity against Staphylococcus aureus SO183 at concentrations of 0.090 g/L and 0.150 g/L and against identified Pseudomonas aeruginosa at a concentration of 0.150 g/L. Pseudomonas aeruginosa strain F29, was isolated from pig fecal matter collected from a mixed animal farm in Ibadan, Nigeria via the pour plate method, identified through biochemical tests and confirmed through molecular studies. Fourier transform infrared (FTIR) spectroscopy of the bioflocculant revealed the presence of carboxyl, aromatic alcohol, alkene, halo and polysulfide functional groups. Scanning electron microscopy (SEM) revealed a clumped and flaky bioflocculant surface while energy dispersive X-ray spectroscopy (EDX) revealed the main chemical elements were chlorine (56.00%), carbon (20.50%), sodium (12.50%), oxygen (4.00%), and phosphorus (3.00%). High performance liquid chromatography (HPLC) and mass spectrometry (MS) revealed that the bioflocculant consisted of carbohydrate sugar moieties of glucose, galactose, inositol and mannose, D-ribose, arabinose, rhamnose and xylose; each with varied peaks. The phenolic sulfuric acid method showed that the concentration of these sugars was 0.0059 g/L. The bioflocculant was a polymeric compound composed mainly of carbohydrates and organochlorines, possibly known as a “glyco-organochlorine.” From available documentation, this is the first report of a “glyco-organochlorine” bioflocculant.