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Alkyl glycosides are biodegradable surfactants with excellent physico-chemical properties. Although their wide-range application is considered ecofriendly, their synthesis is not due to the need for toxic organic solvents and corrosive acids as catalysts. Moreover, chemical synthesis results in complex mixtures rather than defined compounds. To overcome both disadvantages as well as the limited solubility of sugars in organic solvents, a highly selective enzymatic synthesis was set up with a β-glucosidase condensing D-glucose and different fatty alcohols in a deep eutectic solvent.

Glycolipids can be synthetized in deep eutectic solvents (DESs) as they possess low water content allowing a reversed lipase activity and thus enables ester formation. Based on this principle, honey can also serve as a media for glycolipid synthesis. Indeed, this supersaturated sugar solution is comparable in terms of physicochemical properties to the sugar-based DESs. Honey-based products being commercially available for therapeutic applications, it appears interesting to enhance its bioactivity. In the current work, we investigate if enriching medical grade honey with in situ enzymatically-synthetized glycolipids can improve the antimicrobial property of the mixture. The tested mixtures are composed of Manuka honey that is enriched with octanoate, decanoate, laurate, and myristate sugar esters, respectively dubbed GOH, GDH, GLH, and GMH. To characterize the bioactivity of those mixtures, first a qualitative screening using an agar well diffusion assay has been performed with methicillin-resistant

Mechanochemical and biocatalytic approaches in modern research are two major assets to develop greener processes. In the present study, these modular tools of sustainability are pointed toward the production of versatile and daily employed compounds such as surfactants. Toward this aim, glycolipids, a class of nonionic surfactants composed of ubiquitous and primary metabolites such as sugar and fatty acid moieties, represent a promising alternative to petroleum-derived surface-active agents. Therefore, the combination of biocatalysis with mechanochemistry aiming at glycolipid synthesis seemed a logical step that was taken in this study for the first time. The monoacylated model compound glucose-6

Adhesion of host cells on the surface of implants is necessary for a healthy ingrowth of the implanted material. One possibility of surface modification is the coating of the implant with a second material with advantageous physical-chemical surface properties for the biological system. The coverage with blood proteins takes place immediately after implantation. It is followed by host-cell interaction on the surface. In this work, the effect of polyelectrolyte multilayer coatings (PEMs) on adhesion and activity of human umbilical vein endothelial cells (HUVECs) was studied. The PEMs were formed from poly(styrenesulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) from solutions with different concentrations of NaCl varying between 0 and 1.0 M. The adhesion of HUVEC and their viability on the PEM is related to the amount of adsorbed proteins from the applied cell growth medium. The amount of adsorbed proteins is controlled not only by the surface charge but also by the internal excess charge of the PEM. The internal excess charge of the PEM was controlled by changing the electrolyte concentration in the deposition solutions.

Glycolipids are biodegradable, non-toxic surfactants with a wide range of applications. Enzymatic esterification or transesterification facilitated in reaction media of low water activity is a reaction strategy for the production of tailor-made glycolipids as a high structural diversity can be achieved. Organic solvents, ionic liquids, and deep eutectic solvents have been applied as reaction media. However, several challenges need to be addressed for efficient (trans-)esterification reactions, especially for the lipophilization of polar substrates. Therefore, crucial parameters in (trans-)esterification reactions in conventional and non-conventional media are discussed and compared in this review with a special focus on glycolipid synthesis.

Glycolipids are biosurfactants with a wide range of structural diversity. They are biodegradable, based on renewables, ecocompatible and exhibit high surface activity. Still, studies comparing glycolipids and conventional surfactants in terms of interfacial properties and foaming performance are lacking. Here, we compared interfacial and foaming properties of microbial and enzymatically synthesized glycolipids to those of the widely-used, conventional surfactant sodium dodecyl sulfate (SDS). The enzymatically produced sorbose monodecanoate, as well as microbially produced di-rhamno-di-lipids exhibited high foam stabilizing properties, similar to those of SDS. However, sophorolipid and mono-rhamno-di-lipids did not produce metastable foams. An appropriate selection of head and tail groups depending on the application of interest is therefore necessary. Then, glycolipids can serve as an ecofriendly and efficient alternative to petroleum-based surfactants, even at substantially lower concentrations than

Glycolipids are biodegradable, non-toxic surfactants with a wide range of applications. Enzymatic esterification or transesterification facilitated in reaction media of low water activity is a reaction strategy for the production of tailor-made glycolipids as a high structural diversity can be achieved. Organic solvents, ionic liquids, and deep eutectic solvents have been applied as reaction media. However, several challenges need to be addressed for efficient (trans-)esterification reactions, especially for the lipophilization of polar substrates. Therefore, crucial parameters in (trans-)esterification reactions in conventional and non-conventional media are discussed and compared in this review with a special focus on glycolipid synthesis.

Environmentally friendly and biodegradable reaction media are an important part of a sustainable glycolipid production in the transition to green chemistry. Deep eutectic solvents (DESs) are an ecofriendly alternative to organic solvents. So far, only hydrophilic DESs were considered for enzymatic glycolipid synthesis. In this study, a hydrophobic DES consisting of (-)-menthol and decanoic acid is presented for the first time as an alternative to hydrophilic DES. The yields in the newly introduced hydrophobic DES are significantly higher than in hydrophilic DESs. Different reaction parameters were investigated to optimize the synthesis further. Twenty milligrams per milliliter iCalB and 0.5 M glucose resulted in the highest initial reaction velocity for the esterification reaction, while the highest initial reaction velocity was achieved with 1.5 M glucose in the transesterification reaction. The enzyme was proven to be reusable for at least five cycles without significant loss of activity.

The Mediterranean sponge Halichondria (Halichondria) panicea was explored as a novel matrix for the isolation of biosurfactant-producing bacteria. A total of 38 (out of 56) isolates gave a good response to the employed screening tests (e.g., stable emulsion detection, surface tension measurement, hemolytic activity, and blue agar plate assay) and were selected for further analyses. The thin layer chromatography revealed a possible glucidic composition of biosurfactants. Most promising strains, i.e., those able to produce stable emulsion with percentage higher than 30% and yellow spots on TLC plates, were affiliated to the genera Pseudovibrio, Acinetobacter, and Bacillus. The biosurfactant production by two isolates (i.e., Acinetobacter sp. SpN134 and Pseudovibrio sp. SpE85) was evaluated under different culture conditions, in terms of temperature, NaCl concentration, and pH. Surface tension reduction ability was more stable than the emulsification, and resulted differently influenced by salinity, temperature, and pH. Acinetobacter sp. SpN134 resulted particularly efficient and competitive if compared with other well-known biosurfactant producers. Data suggest that sponges may represent a promising matrix for the isolation of biosurfactant-producing bacteria, reinforcing the growing interest towards filter-feeding organisms as underexplored sources of specialized bacteria.

International audience; Four bacterial strains isolated from peat bog soil or swampy meadow in Baden-Württemberg (Germany) and found to have rrs sequences close to that of Rouxiella chamberiensis were compared to this species by using multi-locus sequence analysis and phenotypic tests. The four strains constituted two discrete groups (referred to as the Baden and the Silva groups) belonging to the genus Rouxiella. These groups differed in their ability to grow at 37 °C, reduce nitrate into nitrite, and to produce acid from several carbohydrates. Two novel species are, therefore, proposed: Rouxiella badensis sp. nov. for the Baden group (type strain, 323T=CIP 111153T=DSM 100043T) and Rouxiella silvae for the Silva group (type strain, 213T=CIP 111154T=DSM 103735T). The definition of the genus Rouxiellahas also been emended in order to take these two novel species into account.

Current Status and Future Prospects of Biocatalysis in Deep Eutectic Solvents. 17. Euro Fed Lipid Congress

Environmental friendly (bio-) chemical synthesis reactions are getting ever more important for the production of ecofriendly products. In this study a reaction system based on a deep eutectic solvent consisting of choline chloride and various sugars, was used for the enzymatic synthesis of glycolipids. A wide variety of potential substrates were tested for the enzymatic glycolipid synthesis in DES, including various sugars and one anhydro-sugar in combination with up to 9 different fatty acids. It was proven that the described DES-based solvent system is suitable for the enzymatic synthesis of tailor-made glycolipids. The proposed lipase-catalyzed acylation of the different sugars, which are substrate and part of the solvent at the same time, was detected by TLC-MALDI-ToF, ESI-Q-ToF and additional MS/MS experiments. As an example of all the synthesized glycolipids, fragments and m / z signals of the expected glycolipid arabinose-4- O -laurate was detected, and its chemical structure was elucidated via NMR.

The genetic enhancement of Surfactin production increasingly gained attention in the last years, since relatively low product yields limit the industrial application of this biosurfactant. The natural quorum sensing regulation of the srfA operon (coding for the Surfactin synthetase) can reasonably be assumed to be the bottleneck of Surfactin synthesis. Therefore, the replacement of the naturally quorum sensing regulated, and herewith cell density dependent, promoter PsrfA against the Bacillus subtilis endogenous and constitutive promoter Pveg was hypothesized to generally enhance Surfactin yields. The markerless promoter replacement was conducted in the two B. subtilis Surfactin producer strains 3A38 and DSM 10T. The promoter substitution led to an enhancement of Surfactin concentrations in the producer strain 3A38, initially producing only minor amounts of Surfactin (0.07 g/L increased to 0.26 g/L). In contrast, promoter exchange in B. subtilis DSM 10T (wild-type strain producing 0.62 g/L Surfactin) did not achieve an enhancement of Surfactin concentrations (detrimental reduction to 0.04 g/L). These findings implicate that Surfactin synthesis is differently regulated in minor and strong Surfactin producer strains. The hypothesized general enhancement of Surfactin yields after substitution of the native promoter was therefore not confirmed.

A thorough comparison of spacer-mediated covalent and non-covalent immobilization of trypsin on micro-magnetic particles was accomplished in the present study. Trypsin was coupled via diaminoalkanes, aminoalkanoic acids, bovine serum albumin (BSA), and biotin-derivate spacers onto magnetic particles. A comparison of resulting synthetic and hydrolytic activities after immobilization was performed. Whereas hydrolytic trypsin activity was measured employing N -α-benzoyl- dl -arginine 4-nitroanilide (BAPNA) assay, synthetic trypsin activity was measured employing a dipeptide synthesis assay. Within spacer-mediated trypsin immobilization, diaminoalkanes, aminoalkanoic acids and biotin spacers showed up to 40% increased synthetic specific activity of trypsin compared to the spacer-free method. Within the hydrolytic reaction type, coupling of trypsin via diaminoalkanes and biotin spacers resulted in a specific activity increase of up to 30%. BSA-bound trypsin displayed only minor increasing effects on both activities of trypsin. Furthermore, protein loading-dependent specific synthetic and hydrolytic activities were evaluated for 8-aminooctanoic acid, 12-aminododecanoic acid and 1,12-diamonododecane as spacers and compared to the direct covalent binding method. The protein binding capacity of spacer-modified particles was lower compared to the direct binding method. Synthetic activity of 8-aminooctanoic acid-bound trypsin was higher than in the case of the spacer-free method over a broad protein loading range with an up to 10-fold increase. The hydrolytic activity was increased by 64% using 8-aminooctanoic acid as spacer within a lower protein loading range. Spacer-bound trypsin showed a slightly lowered reusability over ten sequential cycles compared to spacer-free covalent binding method.

Background: The bacterial community responses to oil spill events are key elements to predict the fate of hydrocarbon pollution in receiving aquatic environments. In polar systems, cold temperatures and low irradiance levels can limit the effectiveness of contamination removal processes. In this study, the effects of a simulated acute oil spillage on bacterial communities from polar sediments were investigated, by assessing the role of hydrocarbon mixture, incubation time and source bacterial community in selecting oil-degrading bacterial phylotypes. Methods: The bacterial hydrocarbon degradation was evaluated by gas chromatography. Flow cytometric and fingerprinting profiles were used to assess the bacterial community dynamics over the experimental incubation time. Results: Direct responses to the simulated oil spill event were found from both Arctic and Antarctic settings, with recurrent bacterial community traits and diversity profiles, especially in crude oil enrichment. Along with the dominance of Pseudomonas spp., members of the well-known hydrocarbon degraders Granulosicoccus spp. and Cycloclasticus spp. were retrieved from both sediments. Conclusions: Our findings indicated that polar bacterial populations are able to respond to the detrimental effects of simulated hydrocarbon pollution, by developing into a more specialized active oil degrading community.

‘Ideal’ solvents in biocatalysis have to fulfill a large number of requirements, such as high substrate solubility, high enzyme activity and stability, and positive effects on reaction equilibrium. In the past decades, many enzymatic synthesis routes in water-based and nonaqueous (organic solvents, ionic or supercritical fluids) reaction media have been developed. However, no solvent meets every demand for different reaction types at the same time, and there is still a need for novel solvents suited for different reaction types and applications. Deep eutectic solvents (DESs) have recently been evaluated as solvents in different biocatalytic reactions. They can improve substrate supply, conversion, and stability. The best results were obtained when the DES is formed by the substrates of an enzymatic reaction.

Bioprocess engineering is a highly interdisciplinary field of study which is strongly benefited by practical courses where students can actively experience the interconnection between biology, engineering, and physical sciences. This work describes a lab course developed for 2nd year undergraduate students of bioprocess engineering and related disciplines, where students are challenged with a real‐life bioprocess‐engineering application, the production of recombinant protein in a fed‐batch process. The lab course was designed to introduce students to the subject of operating and supervising an experiment in a bioreactor, along with the analysis of collected data and a final critical evaluation of the experiment. To provide visual feedback of the experimental outcome, the organism used during class was Escherichia coli which carried a plasmid to recombinantly produce enhanced green fluorescent protein (eGFP) upon induction. This can easily be visualized in both the bioreactor and samples by using ultraviolet light. The lab course is performed with bioreactors of the simplest design, and is therefore highly flexible, robust and easy to reproduce. As part of this work the implementation and framework, the results, the evaluation and assessment of student learning combined with opinion surveys are presented, which provides a basis for instructors intending to implement a similar lab course at their respective institution. © 2015 by the International Union of Biochemistry and Molecular Biology, 43(3):189–202, 2015.

Die Enzymtechnologie zahlt zu den wichtigsten Teilgebieten der modernen Biotechnologie. Hierbei handelt es sich um ein hoch interdisziplinares Feld, welches von Beginn bis heute nur durch integrierte interdisziplinare Forschung weiterentwickelt werden konnte. Dieses Kapitel gibt eine Einfuhrung, ausgehend von den Arbeitsgebieten uber die geschichtliche Entwicklung, eine Klassifizierung der Biokatalysatoren bis zu den industriellen Anwendungen. Die Details werden dann in den folgenden Buchkapiteln vorgestellt.

Der Einsatz von Enzymen in ungewohnlichen Reaktionsmedien hat in den vergangenen Jahren vor allem fur die organische Synthese und die chemische Industrie grose Bedeutung gewonnen. Neben polaren und unpolaren organischen Losungsmitteln sowie superkritischen Fluiden sind inzwischen auch ionische Flussigkeiten und stark eutektische Losungen als Reaktionsmedien fur enzymatische Synthesen beschrieben. Die Hauptmotivationen zum Einsatz von Enzymen in ungewohnlichen Reaktionsmedien sind, die Loslichkeit von Substraten und Produkten gegenuber wassrigen Reaktionssystemen deutlich zu erhohen, die anschliesende Aufarbeitung zu vereinfachen und mikrobielle Kontaminationen sowie Neben- und Abbaureaktionen zu vermeiden.

Surfactants are an essential part of detergent or emulsifier formulations and find applications in many cleaning, cosmetic and pharmaceutical products. For many reasons, the trend today is going towards the use of biosurfactants. Among them glycolipids are a highly interesting group of substances and have gained considerable interest. Being biocompatible and biodegradable, they can be obtained either by chemical synthesis, microbial fermentation processes, by enzymatic synthesis or by mixed chemical and biotechnological methods fully originating from renewable resources. Recently, there is much interest in having tailor tailor-made glycolipid surfactants for various applications, but nevertheless the spectrum of substances available is still restricted and their use in industry is still limited, e.g.for example due to high prices and unrecognizedunrecognised structure-function relationships. Here we present a review on existing strategies and methods for the enzymatic synthesis of glycolipid surfactants considering their advantages and still exiting limitations.

Enzymatic synthesis of sugar fatty acid esters in organic solvents is a well-described procedure to synthesize glycolipids. This study aims at replacing these solvents with deep eutectic solvents (DES), a group of solvents that gained more and more interest during the last years, since they can be easily produced from non-toxic resources. Enzymatic glycolipid synthesis in deep eutectic solvents was investigated, employing Candida antarctica lipase B (Novozyme 435) in various deep eutectic solvents. A successful lipase-catalyzed synthesis of glucose fatty acid esters gave proof of this concept, while using the two deep eutectic solvents consisting of choline chloride and urea (CC : U) and choline chloride and glucose (CC : Glc). Additionally the DES consisting of choline chloride and glucose was observed to act as solvent and substrate for the synthesis at the same time. 1 Practical applications Glycolipids find applications in many everyday products like cosmetic and pharmaceutical formulations, food and classic cleaning products, utilizing their good detergent or emulsification properties. Glycolipids can, among other routes, be synthesized via lipase-catalyzed reactions, which are often carried out in organic solvents. By replacing these organic solvents with more ecologically friendly solvents like deep eutectic solvents, the reaction might be improved and the amount of waste produced could be reduced. The lipase-catalyzed synthesis of glucose-6-O-hexanoate employing glucose and vinyl hexanoate in different deep eutectic solvents was demonstrated within the manuscript.

Surfactants are an essential part of detergent or emulsifier formulations and find applications in food, cleaning, cosmetic and pharmaceutical products. Glycolipids are among the best studied surfactants originating from renewable resources and can be obtained by chemical synthesis, fermentation processes as well as by enzymatic syntheses and have gained considerable interest in recent years. The use of suitable enzymes not only facilitates the synthesis of new tailor-made glycolipids, but also allows targeted modification of known microbial glycolipids. Thereby, novel glycolipids may arise with enhanced surfactant properties, which might exhibit interesting bioactive properties as well. Here we present an overview of the advantages, strategies and important parameters regarding the enzymatic synthesis and modification of surface-active glycolipids. Within this article different strategies and advantages of the enzymatic synthesis and modification of glycolipids are discussed.

The thermophilic 'Geobacilli' are important sources of thermostable enzymes and other biotechnologically relevant macromolecules. The present work reports the high quality draft genome sequences of previously unsequenced type strains of Geobacillus uzenensis (DSM 23175T), G. thermocatenulatus (DSM 730T) and Parageobacillus galactosidasius (DSM 18751T). Phylogenomic analyses revealed that DSM 18751T and DSM 23175T represent later heterotypic synonyms of P. toebii and G. subterraneus, respectively, while DSM 730T represents the type strain for the species G. thermocatenulatus. These genome sequences will contribute towards a deeper understanding of the ecological and biological diversity and the biotechnological exploitation of the 'geobacilli'.

A microtiter plate-based assay was developed to evaluate the ability of lipases to perform transesterifications when employed in different organic solvents. A 4-nitrophenol assay was carried out employing seven different lipase formulations and two fatty acid methyl esters with different chain lengths in a total of six organic solvents with logP values approximately between 1 and −1. This assay delivered results within comparatively short times measured by a color reaction and thus facilitates the choice of an enzyme-solvent combination for the synthesis of glycolipids. To validate the findings, glycolipid syntheses were performed using the same lipase formulation in the same solvents. When comparing the results obtained using the microtiter plate-based assay to the results of the glycolipid syntheses using the same lipases and solvents, matching results were obtained.

Biosurfactants increasingly gain attention due to the manifold of possible applications and production on the basis of renewable resources. Owing to its various characteristics, Surfactin is one of the most studied biosurfactants. Since its discovery, several Surfactin producers have been identified, but their capacity to produce Surfactin has not been evaluated in a comparison. Six different Bacillus strains were analyzed regarding their ability to produce Surfactin in model fermentations with integrated foam fractionation, for in situ product enrichment and removal. Three of the investigated strains are commonly used in Surfactin production (ATCC 21332, DSM 3256, DSM 3258), whereas two Bacillus strains are described for the first time (DSM 1090, LM43a50°C) as Surfactin producers. Additionally, the Bacillus subtilis type strain DSM 10(T) was included in the evaluation. Interestingly, all strains, except DSM 3256, featured high values for Surfactin recovered from foam in comparison to other studies, ranging between 0.4 and 1.05 g. The fermentation process was characterized by calculating procedural parameters like substrate yield Y X/S, product yield Y P/X, specific growth rate μ, specific productivity q Surfactin, volumetric productivity q Surfactin, Surfactin and bacterial enrichment as well as Surfactin recovery. The strains differ most in specific and volumetric productivity; nevertheless, it is evident that it is not possible to name a Bacillus strain that is the most appropriate for the production of Surfactin under these conditions. In contrast, it becomes apparent that the choice of a specific strain should depend on the applied fermentation conditions.

Actinomycetales are known to produce various secondary metabolites including products with surface-active and emulsifying properties known as biosurfactants. In this study, the nonpathogenic actinomycetes Tsukamurella spumae and Tsukamurella pseudospumae are described as producers of extracellular trehalose lipid biosurfactants when grown on sunflower oil or its main component glyceryltrioleate. Crude extracts of the trehalose lipids were purified using silica gel chromatography. The structure of the two trehalose lipid components (TL A and TL B) was elucidated using a combination of matrix-assisted laser desorption/ionization time-of-flight/time-of-flight/tandem mass spectroscopy (MALDI-ToF-ToF/MS/MS) and multidimensional NMR experiments. The biosurfactants were identified as 1-α-glucopyranosyl-1-α-glucopyranosid carrying two acyl chains varying of C4 to C6 and C16 to C18 at the 2' and 3' carbon atom of one sugar unit. The trehalose lipids produced demonstrate surface-active behavior and emulsifying capacity. Classified as risk group 1 organisms, T. spumae and T. pseudospumae hold potential for the production of environmentally friendly surfactants.

Economic and ecological reasons cause the industry to develop new innovative bio-based processes for the production of oil as renewable feedstock. Petroleum resources are expected to be depleted in the near future. Plant oils as sole substituent are highly criticized because of the competitive utilization of the agricultural area for food and energy feedstock production. Microbial lipids of oleaginous microorganisms are therefore a suitable alternative. To decrease production costs of microbial lipids and gain spatial independence from industrial sites of CO2 emission, a combination of heterotrophic and phototrophic cultivation with integrated CO2 recycling was investigated in this study. A feasibility study on a semi-pilot scale was conducted and showed that the cultivation of the oleaginous yeast Cryptococcus curvatus on a 1.2-L scale was sufficient to supply a culture of the oleaginous microalgae Phaeodactylum tricornutum in a 21-L bubble column reactor with CO2 while single cell oils were produced in both processes due to a nutrient limitation.

Oligopeptides are of high importance for various industrial applications, e.g. cosmetical or medical. Homooligomerizations and co-oligomerizations with anionic amino acid esters are well described but a successful synthesis of cationic heterooligopeptides has been missing so far. The present study reports the ficain-catalyzed heterooligomerizations of LysOEt with MetOEt, leading to cationic heterooligopeptides with a yield up to 49.5% (w/w). MALDI-ToF/ToF-MS analyses proved successful syntheses of cationic heterooligopeptides with a DP between 7 and 10 amino acid residues, with the enzyme exhibiting a clear preference for methionine.

Here, we describe the use of biochemically derived fatty acid derivatives (ω- and ω-1 hydroxy fatty acid methyl esters) as starting materials for renewable polyesters and polyamides. The required long-chain monomers were obtained by chemical derivatization of biochemically derived fatty acids. Thus, a long chain diester and a ω-amino fatty acid methyl ester were synthesized and used to prepare polyester PE 32–34:32–34 and polyamide PA 16. The polyester was prepared by transesterification using 5 mol% of the catalyst tin(II) 2-ethylhexanoate (Sn(Oct)2), leading to an average molecular weight of Mn = 7.4 kDa and a melting point of 109 °C. PA 16 was prepared by amidation using TBD as catalyst and resulting in an average molecular weight of Mn = 20.3 kDa and a melting point of 166 °C.

Influence of different parameters on biosurfactant (BS) activity was carried out on strains that were isolated from the polychaetes Megalomma claparedei, Sabella spallanzanii and Branchiomma luctuosum and additional 30 strains that were previously identified as potential BS producers from crude oil enrichments of the same polychaete specimens. The selection of BS-producing strains from polychaete natural samples was carried out by using standard screening tests. The BS activity by each isolate was evaluated for the effect of salinity and temperature on emulsion production and surface tension reduction, during incubation in mineral medium supplemented with tetradecane or diesel oil. All isolates showed a similar time course of BS activity, and the latter was more influenced by salinity rather than temperature. Some of the BS producers belonged to genera that have not (i.e. Citricoccus, Cellulophaga, Tenacibaculum and Maribacter) or have poorly been (Psychrobacter, Vibrio, and Pseudoalteromonas) reported as able to produce BSs. This is remarkable as some of them have previously been detected in hydrocarbon-enriched samples. Results confirm that filter-feeding polychaetes are an efficient source for the isolation of BS producers.