Production and structural elucidation of trehalose tetraesters (biosurfactants) from a novel alkanothrophic Rhodococcus wratislaviensis strain

Abstract

Aims: To isolate a biosurfactant‐producing bacterial strain and to identify and characterize the chemical structure and properties of its biosurfactants. Methods and Results: The bacterium Rhodococcus wratislaviensis BN38, isolated from soil, was found to produce glycolipid biosurfactants when grown on 2%n‐hexadecane. The glycolipids were isolated by chromatography on silica gel columns and their structures elucidated using a combination of multidimensional NMR and ESI‐MS/MS techniques. The main product was identified as 2,3,4,2′‐trehalose tetraester with molecular mass of 876 g mol−1. It was also noted that the biosurfactant was produced under nitrogen‐limiting conditions and could not be synthesized from water‐soluble substrates. The purified product showed extremely high surface‐active properties. Conclusions: The glycolipid biosurfactant produced by the alkanothrophic strain R. wratislaviensis BN38 was characterized to be 2,3,4,2′‐trehalose tetraester which exhibited high surfactant activities. Significance and Impact of the Study: Strain BN38 of R. wratislaviensis is a potential candidate for use in bioremediation applications or in biosurfactant exploration.

Simultaneous Biodegradation of Phenol and n-Hexadecane by Cryogel Immobilized Biosurfactant Producing Strain Rhodococcus wratislawiensis BN38

“…During the biodegradation of both hydrophilic and hydrophobic xenobiotics, enhanced biosurfactant production (500 mg/l) was quantified. Biosurfactant levels increased exponentially and reached maximum levels in stationary growth as described previously (Tuleva et al, 2008). A significant decrease of the surface tension to 32 mN/m was also registered, accompanied by the formation of stable emulsions with kerosene.…”

“…The R. wrati slawiensis BN38, employed in this study was isolated from soil polluted with hydrocarbons by a standard enrichment technique (Tuleva et al, 2008 O, 0.2 and phenol and nhexadecane at 500 mg/l, unless otherwise mentioned, was used. The pH of the medium was adjusted to 7.0.…”

“…Suggested mechanisms for the uptake of hydrophobic contaminants by degrad ing bacteria include direct contact of the substrates with microorganisms having a high cell surface hydropho bicity and biosurfactantmediated uptake by micro organisms capable of producing biosurfactants (Zhao et al, 2011). Thus, when grown on phenol and hexa decane strain BN38 produced a bisurfactant possess ing the same fragmentation pattern from mass spectra analysis of trehalose tetraester as already described (Tuleva et al, 2008). Initially the cells of R. wratislawiensis BN38 showed 80% adhesion to hexadecane indicat ing high cell surface hydrophobicity.…”

Production and applications of trehalose lipid biosurfactants

“…Kurane et al [10] reported flocculating properties caused by glycolipids of R. erythropolis S-1; the carbohydrate is acylated with C10-C22 saturated and unsaturated fatty acids, C35-C40 mycolic acids, hexanedioic, dodecanedioic acids, 10-methyl hexadecanoic and 10-methyl octadecanoic acids. Several studies have resulted in the discovery of novel types of trehalolipids including: mono-, di-and tri-corynomycolates [11][12][13], mono-, di-, tetra-, hexa-and octa-acylated derivatives of trehalose [9,11], trehalose tetraesters [8,[14][15][16][17] and succinoyl trehalose lipids [18,19].…”

Uptake Modes of Fluoranthene by StrainRhodococcusSp. Bap-1

“…After that, 5 mL of sulfuric acid were added rapidly against the side of the test tube and the test tube was allowed to stand for 10 min in order to obtain good mixing. The absorbance of the mixture was measured at 480 nm (Varian, USA); trehalose was used as the standard (32). For each concentration gradient, three independent measurements were made, with the standard deviation being within 5%.…”