Sustainable Exopolysaccharide Production by CECT908 Using Corn Steep Liquor and Sugarcane Molasses as Sole Substrates.

Microbial exopolysaccharides (EPS) are promising alternatives to synthetic polymers in a variety of applications. Their high production costs, however, limit their use despite their outstanding properties. The use of low-cost substrates such as agro-industrial wastes in their production, can help to boost their market competitiveness.

Zymomonas mobilis as an emerging biotechnological chassis for the production of industrially relevant compounds.

Zymomonas mobilis is a well-recognized ethanologenic bacterium with outstanding characteristics which make it a promising platform for the biotechnological production of relevant building blocks and fine chemicals compounds. In the last years, research has been focused on the physiological, genetic, and metabolic engineering strategies aiming at expanding Z. mobilis ability to metabolize lignocellulosic substrates toward biofuel production.

Improved method for the extraction of high-quality DNA from lignocellulosic compost samples for metagenomic studies.

The world economy is currently moving towards more sustainable approaches. Lignocellulosic biomass has been widely used as a substitute for fossil sources since it is considered a low-cost bio-renewable resource due to its abundance and continuous production. Compost habitats presenting high content of lignocellulosic biomass are considered a promising source of robust lignocellulose-degrading enzymes.

Corksorb Enhances Alkane Degradation by Hydrocarbonoclastic Bacteria.

Biosorbent materials are effective in the removal of spilled oil from water, but their effect on hydrocarbonoclastic bacteria is not known. Here, we show that corksorb, a cork-based biosorbent, enhances growth and alkane degradation by B4 (Ro) and SK2 (Ab). Ro and Ab degraded 96 ± 1% and 72 ± 2%, respectively, of a mixture of -alkanes (2 g L) in the presence of corksorb.

Characterization of levan produced by a Paenibacillus sp. isolated from Brazilian crude oil.

A levan-type fructooligosaccharide was produced by a Paenibacillus strain isolated from Brazilian crude oil, the purity of which was 98.5% after precipitation with ethanol and dialysis. Characterization by FTIR, NMR spectroscopy, GC-FID and ESI-MS revealed that it is a mixture of linear β(2 → 6) fructosyl polymers with average degree of polymerization (DP) of 18 and branching ratio of 20.

Sustainable Surfactin Production by Using Crude Glycerol from Different Wastes.

Most biosurfactants are obtained using costly culture media and purification processes, which limits their wider industrial use. Sustainability of their production processes can be achieved, in part, by using cheap substrates found among agricultural and food wastes or byproducts. In the present study, crude glycerol, a raw material obtained from several industrial processes, was evaluated as a potential low-cost carbon source to reduce the costs of surfactin production by #309.

Rhamnolipids inhibit aflatoxins production in Aspergillus flavus by causing structural damages in the fungal hyphae and down-regulating the expression of their biosynthetic genes.

Aflatoxins are hepatotoxic and carcinogenic fungal secondary metabolites that usually contaminate crops and represent a serious health hazard for humans and animals worldwide. In this work, the effect of rhamnolipids (RLs) produced by Pseudomonas aeruginosa #112 on the growth and aflatoxins production by Aspergillus flavus MUM 17.14 was studied in vitro.

Sustainable Lipase Production by Diutina rugosa NRRL Y-95 Through a Combined Use of Agro-Industrial Residues as Feedstock.

The potential use of alternative culture media towards the development of a sustainable bioprocess to produce lipases by Diutina rugosa is clearly demonstrated. First, a synthetic medium containing glucose, peptone, yeast extract, oleic acid, and ammonium sulfate was proposed, with lipase activity of 143 U/L. Then, alternative culture media formulated with agro-industrial residues, such as molasses, corn steep liquor (CSL), and olive mill waste (OMW), were investigated.

Synergistic effect of hen egg white lysozyme and lysosomotropic surfactants on cell viability and membrane permeability.

The interactions between two types of quaternary ammonium surfactants (N,N,N-trimethyl-2-(dodecanoyloxy)ethaneammonium bromide (DMM-11) and N,N,N-trimethyl-2-(dodecanoyloxy)propaneammonium bromide (DMPM-11)) and hen egg white lysozyme were studied through several techniques, including isothermal titration calorimetry (ITC), circular dichroism (CD) and fluorescence spectroscopy, and surface tension measurement. The average number of surfactants interacting with each molecule of lysozyme was calculated from the biophysical results. Moreover, the CD results showed that the conformation of lysozyme changed in the presence of DMM-11 and DMPM-11.

Metal-Biosurfactant Complexes Characterization: Binding, Self-Assembly and Interaction with Bovine Serum Albumin.

Studies on the specific and nonspecific interactions of biosurfactants with proteins are broadly relevant given the potential applications of biosurfactant/protein systems in pharmaceutics and cosmetics. The aim of this study was to evaluate the interactions of divalent counterions with the biomolecular anionic biosurfactant surfactin-C through molecular modeling, surface tension and dynamic light scattering (DLS), with a specific focus on its effects on biotherapeutic formulations. The conformational analysis based on a semi-empirical approach revealed that Cu ions can be coordinated by three amide nitrogens belonging to the surfactin-C cycle and one oxygen atom of the aspartic acid from the side chain of the lipopeptide.

Microbial Surfactants: Alternative to Vegetable Oil Surfactants.

Biosurfactants, surface active molecules synthesized by microorganisms, represent a promising alternative to the synthetic surfactants in many different applications. Among them, rhamnolipids have attracted considerable attention in the last years due to their extraordinary surface-active properties and biological activities. Rhamnolipids are usually synthesized by the gram-negative bacterium Pseudomonas aeruginosa as complex mixtures of different congeners.

Biomolecular interactions of lysosomotropic surfactants with cytochrome c and its effect on the protein conformation: A biophysical approach.

The molecular interactions between two single-chain lysosomotropic surfactants DMM-11 (2-Dodecanoyloxyethyl)trimethylammonium bromide) and DMPM-11 (2-Dodecanoyloxypropyl)trimethylammonium bromide) with a small heme-protein (cytochrome c (cyt-c)) in Hepes buffer (pH = 7.4) were extensively investigated by surface tension, dynamic light scattering (DLS), circular dichroism (CD) and fluorescence spectroscopy in combination with molecular dynamic simulation techniques. The results demonstrated that surfactants can destroy the hydrophobic cavity of cyt-c, make the α-helical become loose and convert it into the β-sheet structure.

The biopolymer produced by Rhizobium viscosum CECT 908 is a promising agent for application in microbial enhanced oil recovery.

Polymer flooding is one of the most promising techniques used to increase the productivity of mature oil reservoirs. Polymers reduce the mobility ratio of the injected water relative to the crude oil, improving the displacement of the entrapped oil and consequently, increasing oil recovery. Biopolymers such as xanthan gum have emerged as environmentally friendly alternatives to the chemical polymers commonly employed by the oil industry.

Improvement of biosurfactant production by Wickerhamomyces anomalus CCMA 0358 and its potential application in bioremediation.

In this work, biosurfactant production by Wickerhamomyces anomalus CCMA 0358 was increased through the development of an optimized culture medium using response surface methodology. The optimized culture medium contained yeast extract (4.64 g/L), ammonium sulfate (4.

Sodium chloride effect on the aggregation behaviour of rhamnolipids and their antifungal activity.

In this work, the antifungal activity of rhamnolipids produced by Pseudomonas aeruginosa #112 was evaluated against Aspergillus niger MUM 92.13 and Aspergillus carbonarius MUM 05.18.

Physicochemical study of biomolecular interactions between lysosomotropic surfactants and bovine serum albumin.

The interactions between two cationic lysosomotropic surfactants (2-dodecanoyloxyethyl)trimethylammonium bromide (DMM-11) and (2-dodecanoyloxypropyl)trimethylammonium bromide (DMPM-11) with bovine serum albumin (BSA) in Hepes buffer (pH=7.4) were systematically studied by surface tension, fluorescence and circular dichroism (CD) spectroscopy and isothermal titration calorimetry (ITC). Furthermore, the size of the micellar aggregates and the polydispersity indexes of both cationic surfactants were studied by dynamic light scattering technique (DLS).

The yeast-like fungus Aureobasidium thailandense LB01 produces a new biosurfactant using olive oil mill wastewater as an inducer.

In this study, the biosurfactant production by an Aureobasidium thailandense LB01 was reported for the first time. Different agro-industrial by-products (corn steep liquor, sugarcane molasses, and olive oil mill wastewater) were evaluated as alternative low-cost substrates. The composition of the culture medium was optimized through response surface methodology.

New glycolipid biosurfactants produced by the yeast strain Wickerhamomyces anomalus CCMA 0358.

In this work, biosurfactant production by several yeast strains was evaluated using different culture media. The best results were obtained with the strain Wickerhamomyces anomalus CCMA 0358 growing in a culture medium containing glucose (1g/L) and olive oil (20g/L) as carbon sources. This strain produced 2.

Structure and mode of action of cyclic lipopeptide pseudofactin II with divalent metal ions.

The interaction of natural lipopeptide pseudofactin II with a series of doubly charged metal cations was examined by matrix-assisted laser-desorption ionization-time of flight (MALDI-TOF) mass spectrometry and molecular modelling. The molecular modelling for metal-pseudofactin II provides information on the metal-peptide binding sites. Overall, Mg(2+), Ca(2+) and Zn(2+) favor the association with oxygen atoms spanning the peptide backbone, whereas Cu(2+) is coordinated by three nitrogens.

Valorization of agro-industrial wastes towards the production of rhamnolipids.

In this work, oil mill wastewater (OMW), a residue generated during olive oil extraction, was evaluated as an inducer of rhamnolipid production. Using a medium containing as sole ingredients corn steep liquor (10%, v/v), sugarcane molasses (10%, w/v) and OMW (25%, v/v), Pseudomonas aeruginosa #112 produced 4.5 and 5.

Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications.

Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens), and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies.

Biosurfactant production by Bacillus subtilis using corn steep liquor as culture medium.

In this work, biosurfactant production by Bacillus subtilis #573 was evaluated using corn steep liquor (CSL) as culture medium. The best results were obtained in a culture medium consisting of 10% (v/v) of CSL, with a biosurfactant production of about 1.3 g/l.

Novel bioemulsifier produced by a Paenibacillus strain isolated from crude oil.

Background: Surface active compounds produced by microorganisms are attracting a pronounced interest due to their potential advantages over their synthetic counterparts, and to the fact that they could replace some of the synthetics in many environmental and industrial applications.

Results: Bioemulsifier production by a Paenibacillus sp. strain isolated from crude oil was studied.