Screening for exopolysaccharide-producing bacteria from sub-tropical polluted groundwater

Abstract

A selection of exopolysaccharide (EPS)--producing bacterial strains was conducted in groundwater adjacent to an old controlled landfill in the City of São Carlos (São Paulo, Brazil). The strains were isolated in P and E media under aerobic and microacrophilic conditions at 25 degrees C. A total of 26 strains were isolated and based on the mucoid mode of the colonies, 6 were selected and their morphological, physiological and biochemical aspects were characterized. All strains presented pigmentation, ranging from yellow to orange and from pink to salmon, with a shiny glistening aspect in all tested media. Strains Lb, Lc and Lg, which excelled the others with regard to the mucoid mode of the colonies, were selected to be cultured in E medium with alternate sucrose and glucose as carbon sources in anaerobiosis at 25 degrees C to analyze the production of EPS. Strains Lc and Lg were classified as being of order Actinomycelates, suborder Corynebacterineae. Lg strain was identified as Gordonia polyisoprenivorans and Lc strain did not correspond to a known description and therefore a more detailed study is under preparation. Considering all ecological aspects and the metabolic potential associated with the microorganisms of the environment studied, as well as the capacity to produce pigment and EPS, and the presence of G. polyisoprenivorans, a rubber degrader bacterium, the potential of the groundwater analyzed is evident as a source of microorganisms to be utilized in studies related to environmental remediation.

Gordonia polyisoprenivorans from groundwater contaminated with landfill leachate in a subtropical area: characterization of the isolate and exopolysaccharide production

“…The ability of strains of G. polyisoprenivorans to produce smooth and rough variants was previously noted in strains VH2 (2,23) and Y2K (2). Fusconi and Godinho (14) selected this strain for EPS production studies on the basis of the mucoid aspect of colonies on solid media and the mucoid mode of growth in liquid media, characteristics that indicate production of large amounts of EPS by bacterial strains (8,18). Experimental measurement of EPS produced by Lc strain during growth on one out of the two carbon sources confirmed predictions of EPS production by the strain.…”

“…The forth strain was isolated from a clinical specimen (blood sample taken from a aptient'sHickman catheter) (20). The fifth strain (G. polyisoprenivorans CCT 7137), was isolated from subtropical landfill-leachete contaminatel groundwater in Brazil (14) and the sixth, which is the strain described in the present work (strain Lc), was isolated from the same groundwater, during a screening for EPS-producing bacteria (14). Lc is the second strain of G. polyisoprenivorans detected in groundwater adjacent to the old municipal landfill of the city of São Carlos and the first that is being studied for EPS production.…”

“…During a screening for EPS-producing bacteria, strain Lc was isolated from the groundwater beneath the old municipal landfill of São Carlos City (upstate São Paulo, Brazil) (14). The strain was deposited at the Tropical Culture Collection (Fundação Tropical de Pesquisas e Tecnologia "André Tosello", Campinas, Brazil) under accession number CCT 7277.…”

Evaluation of biofilm formation by exopolysaccharide-producer strains of thermophilic lactic acid bacteria isolated from Algerian camel milk

“…The selection process of EPS-producing bacterial strains was fundamentally based on the development of mucoid aspect of strain colonies, according to Ricciardi et al (1997); and Ruas-Madiedo and de los Reyes-Gavilan (2005), by studying the production of EPS on solid media, by lactic acid bacteria. In other studies, the detection of the mucoid character was related to EPS production by bacteria isolated from polluted water (Fusconi and Godinho, 2002). The presence of EPS can be recognized by the formation of colonies in mucous solid medium (Gomez, 2006).…”

Production of Antibacterial and Larvicidal Extracellular Polysaccharide from Pseudomonas aeruginosa Strain b01 Isolated from Wastewater

“…The samples were serially diluted and plated on nutrient agar plates [(in g/l), (peptic digest of animal tissue, 5.0; beef extract, 1.5; yeast extract, 1.5; sodium chloride, 5.0; and agar, 15)]. All plates were incubated at 37 °C for 48 h. The potent EPS producing isolate was retained by observing for good mucoid colony morphology (Fusconi and Godinho, 2002).…”