Characterization of new biosurfactant produced by Trichosporon montevideense CLOA 72 isolated from dairy industry effluents

Exploring fungal bioemulsifiers: insights into chemical composition, microbial sources, and cross-field applications

The demand for emulsion-based products is crucial for economic development and societal well-being, spanning diverse industries such as food, cosmetics, pharmaceuticals, and oil extraction. Formulating these products relies on emulsifiers, a distinct class of surfactants. However, many conventional emulsifiers are derived from petrochemicals or synthetic sources, posing potential environmental and human health risks. In this context, fungal bioemulsifiers emerge as a compelling and sustainable alternative, demonstrating superior performance, enhanced biodegradability, and safety for human consumption. From this perspective, the present work provides the first comprehensive review of fungal bioemulsifiers, categorizing them based on their chemical nature and microbial origin. This includes polysaccharides, proteins, glycoproteins, polymeric glycolipids, and carbohydrate-lipid-protein complexes. Examples of particular interest are scleroglucan, a polysaccharide produced by Sclerotium rolfsii, and mannoproteins present in the cell walls of various yeasts, including Saccharomyces cerevisiae. Furthermore, this study examines the feasibility of incorporating fungal bioemulsifiers in the food and oil industries and their potential role in bioremediation events for oil-polluted marine environments. Finally, this exploration encourages further research on fungal bioemulsifier bioprospecting, with far-reaching implications for advancing sustainable and eco-friendly practices across various industrial sectors.

Microbial surfactants: characteristics, production and broader application prospects in environment and industry

Microbial surfactants are green molecules with high surface activities having the most promising advantages over chemical surfactants including their ability to efficiently reducing surface and interfacial tension, nontoxic emulsion-based formulations, biocompatibility, biodegradability, simplicity of preparation from low cost materials such as residual by-products and renewable resources at large scales, effectiveness and stabilization under extreme conditions and broad spectrum antagonism of pathogens to be part of the biocontrol strategy. Thus, biosurfactants are universal tools of great current interest. The present work describes the major types and microbial origin of surfactants and their production optimization from agro-industrial wastes in the batch shake-flasks and bioreactor systems through solid-state and submerged fermentation industries. Various downstream strategies that had been developed to extract and purify biosurfactants are discussed. Further, the physicochemical properties and functional characteristics of biosurfactants open new future prospects for the development of efficient and eco-friendly commercially successful biotechnological product compounds with diverse potential applications in environment, industry, biomedicine, nanotechnology and energy-saving technology as well.

A New Biosurfactant/Bioemulsifier from Gordonia alkanivorans Strain 1B: Production and Characterization

Biosurfactants and bioemulsifiers (BS/BE) are naturally synthesized molecules, which can be used as alternatives to traditional detergents. These molecules are commonly produced by microorganisms isolated from hydrocarbon-rich environments. Gordonia alkanivorans strain 1B was originally found in such an environment, however little was known about its abilities as a BS/BE producer. The goal of this work was to access the potential of strain 1B as a BS/BE producer and perform the initial characterization of the produced compounds. It was demonstrated that strain 1B was able to synthesize lipoglycoprotein compounds with BS/BE properties, both extracellularly and adhered to the cells, without the need for a hydrophobic inducer, producing emulsion in several different hydrophobic phases. Using a crude BS/BE powder, the critical micelle concentration was determined (CMC = 16.94 mg/L), and its capacity to reduce the surface tension to a minimum of 35.63 mN/m was demonstrated, surpassing many commercial surfactants. Moreover, after dialysis, emulsification assays revealed an activity similar to that of Triton X-100 in almond and sunflower oils. In benzene, the E24 value attained was 83.45%, which is 30% greater than that of the commercial alternative. The results obtained highlight for the presence of promising novel BS/BE produced by strain 1B.

Bioremediation of an agricultural saline soil contaminated with endosulfan and Escherichia coli by an active surface agent induced in a Penicillium crustosum culture

This study evaluates the production of a biological active surface agent (BASA) through its surface tension (ST) and emulsifying activity (E₂₄) for endosulfan degradation (ED) and Escherichia coli growth inhibition (EcGI) in an agricultural saline soil. The fungus, identified as Penicillium crustosum was isolated from the Citrus sinensis peel (CsP), then the surface properties were evaluated in 9 culture media through a Taguchi L9 experimental design. The culture conditions included: stirring speed, pH, carbon (C) and nitrogen (N) sources; being glucose, NH₄N0₃, 120 rpm and pH of 5, the most significant parameters in the BASA production. The BASA identified as a lipopeptide type, showed a ST = 38 mN m^-1 and E₂₄=71%. Both properties were stable at 80 °C, while ST presented stability in the pH range of 2 - 12, and a saline concentration of 200 g L^-1; E₂₄ was also stable at a pH between 8-12. Further application of BASA and fungal inoculum to a contaminated agricultural saline soil presented an EcGI of 99.8% on the 8th day, and ED of 92.9 ± 4.7% in 30 days, respectively; being the first report that uses this fungus for pesticide and bacteria elimination from an agricultural saline soil.

Comparative data on effects of alkaline pretreatments and enzymatic hydrolysis on bioemulsifier production from sugarcane straw by Cutaneotrichosporon mucoides

Bioemulsifiers are surface active compounds which could be potentially used in food processing, cosmetic sector and oil recovery. Sugarcane straw (SS), was used as the raw substrate for the production of bio-emulsifiers (BE) by Cutaneotrichosporon mucoides. Three different delignification strategies using dilute sodium hydroxide, sodium sulfite and ammonium hydroxide followed by enzymatic hydrolysis (Cellic CTec 2, 7.5% total solids, 15 FPU/g, 72 h) were studied. Enzyme hydrolysis of ammonium hydroxide pretreated SS showed a maximum of 62.19 ± 0.74 g/l total reducing sugars with 88.35% hydrolytic efficiency (HE) followed by sodium hydroxide (60.06 ± 0.33 g/l; 85.40% HE) and sodium sulfite pretreated SS (57.22 ± 0.52 g/l; 84.71% HE), respectively. The ultrastructure of SS (native and delignified) by fourier transform-infrared and near infrared spectroscopy, revealed notable structural differences. The fermentation of hydrolysates by C. mucoides into bioemulsifiers showing emulsification index (EI) of 54.33%, 48.66% and 32.66% from sodium sulfite, sodium hydroxide, and ammonium hydroxide pretreated SS, respectively.

Anthelmintic efficacy of glycolipid biosurfactant produced by Pseudomonas plecoglossicida: an insight from mutant and transgenic forms of Caenorhabditis elegans

The current research focuses on the production and characterization of glycolipid biosurfactant (GB) from Pseudomonas plecoglossicida and its anthelmintic activity against Caenorhabditis elegans. The GB was purified and characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography and Mass Spectrometry (GC-MS) analysis. Anthelmintic activity of GB was studied at six different pharmacological doses from 10 to 320 µg/mL on C. elegans. Exposure of different developmental stages (L1, L2, L3, L4 and adult) of C. elegans to the GB reduced the survivability of worms in a dose and time-dependent manner. Adult and L4 worms were least susceptible, while L1, L2 and L3 were more susceptible to GB when compared to the untreated control. An increased exposure period drastically reduced the survival rate of worms and reduction in LC₅₀ value. The GB significantly inhibited the development of C. elegans with an IC₅₀ value of 53.14 µg/mL and even reduced the adult body length and egg hatching. Fecundity rate of the worms treated with GB at 20, 40 and 80 µg/mL decreased from 261.90 ± 3.21 to 239.70 ± 5.58, 164.20 ± 5.94 and 44.80 ± 6.22 eggs per worm, respectively. Besides the toxicological effects, prolonged exposure to GB significantly decreased (p ≤ 0.0001) the lifespan of wild type worms under standard laboratory conditions. Additionally, GB was found to be lethal towards ivermectin and albendazole resistant C. elegans strains. Overall, the data indicated that the GB extracted from P. plecoglossicida could be utilized for the control of non-susceptible and resistant gastrointestinal nematodes towards broad spectrum anthelmintic drugs, ivermectin and albendazole.

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 (4.22 g/L), glucose (1.39 g/L) and olive oil (10 g/L). Biosurfactant production using this medium was validated both in flasks and bioreactor, and the surface tension was reduced from 49.0 mN/m up to 31.4 mN/m and 29.3 mN/m, respectively. In both cases, the highest biosurfactant production was achieved after 24 h of growth. W. anomalus CCMA 0358 demonstrated to be a fast biosurfactant producer (24 h) as compared to other yeast strains previously reported (144-240 h). The produced biosurfactant remained stable at high temperature (121 °C), NaCl concentrations as high as 300 g/L, and pH values between 6 and 12. The crude biosurfactant allowed the recovery of 20% of crude oil from contaminated sand, being a promising candidate for application in bioremediation or in the petroleum industry.

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. The bioemulsifier was produced using sucrose with and without adding hydrocarbons (paraffin or crude oil) under aerobic and anaerobic conditions at 40°C. It formed stable emulsions with several hydrocarbons and its emulsifying ability was not affected by exposure to high salinities (up to 300 g/l), high temperatures (100°C-121°C) or a wide range of pH values (2-13). In addition, it presented low toxicity and high biodegradability when compared with chemical surfactants. A preliminary chemical characterization by Fourier Transform Infrared Spectroscopy (FT-IR), proton and carbon nuclear magnetic resonance (1H NMR and 13C CP-MAS NMR) and size exclusion chromatography indicated that the bioemulsifier is a low molecular weight oligosaccharide-lipid complex.

CONCLUSION

The production of a low molecular weight bioemulsifier by a novel Paenibacillus strain isolated from crude oil was reported. To the best of our knowledge, bioemulsifier production by Paenibacillus strains has not been previously reported. The features of this novel bioemulsifier make it an interesting biotechnological product for many environmental and industrial applications. Graphical Abstract Novel bioemulsifier from Paenibacillus sp.

Cost effective technologies and renewable substrates for biosurfactants' production

Diverse types of microbial surface active amphiphilic molecules are produced by a range of microbial communities. The extraordinary properties of biosurfactant/bioemulsifier (BS/BE) as surface active products allows them to have key roles in various field of applications such as bioremediation, biodegradation, enhanced oil recovery, pharmaceutics, food processing among many others. This leads to a vast number of potential applications of these BS/BE in different industrial sectors. Despite the huge number of reports and patents describing BS and BE applications and advantages, commercialization of these compounds remain difficult, costly and to a large extent irregular. This is mainly due to the usage of chemically synthesized media for growing producing microorganism and in turn the production of preferred quality products. It is important to note that although a number of developments have taken place in the field of BS industries, large scale production remains economically challenging for many types of these products. This is mainly due to the huge monetary difference between the investment and achievable productivity from the commercial point of view. This review discusses low cost, renewable raw substrates, and fermentation technology in BS/BE production processes and their role in reducing the production cost.

Advances in utilization of renewable substrates for biosurfactant production

Biosurfactants are amphiphilic molecules that have both hydrophilic and hydrophobic moieties which partition preferentially at the interfaces such as liquid/liquid, gas/liquid or solid/liquid interfaces. Such characteristics enable emulsifying, foaming, detergency and dispersing properties. Their low toxicity and environmental friendly nature and the wide range of potential industrial applications in bioremediation, health care, oil and food processing industries makes them a highly sought after group of chemical compounds. Interest in them has also been encouraged because of the potential advantages they offer over their synthetic counterparts in many fields spanning environmental, food, biomedical, petrochemical and other industrial applications. Their large scale production and application however are currently restricted by the high cost of production and by the limited understanding of their interactions with cells and with the abiotic environment. In this paper, we review the current knowledge and latest advances in the search for cost effective renewable agro industrial alternative substrates for their production.

Inhibition of Candida albicans CC biofilms formation in polystyrene plate surfaces by biosurfactant produced by Trichosporon montevideense CLOA72

This study evaluated the effects of glycolipid-type biosurfactant produced by Trichosporon montevideense CLOA72 in the formation of biofilms in polystyrene plate surfaces by Candida albicans CC isolated from the apical tooth canal. Biofilm formation was reduced up to 87.4% with use of biosurfactant at 16 mg/ml concentration. It has been suggested that the interaction with the cell or polystyrene plate surface could ultimately be responsible for these actions. Therefore, the interaction of C. albicans CC cells with the biosurfactant, as well as the corresponding thermodynamic parameters, have been determined by isothermal titration calorimetry and zeta potential measurements. This process is endothermic (((int)H°=+1284±5 cal/mg OD(600)) occurring with a high increase of entropy (T((int)S°=+10635 cal/mg OD(600)). The caloric energy rate data released during the titulation indicates saturation of the cell-biosurfactant at 1.28 mg/ml OD(600). Also, the zeta potential of the cell surface was monitored as a function of the biosurfactant concentration added to cell suspension showing partial neutralization of net surface charge, since the value of zeta potential ranged from -16 mV to -6 mV during the titration. The changes of cell surface characteristics can contribute to the inhibition of initial adherence of cells of C. albicans in surface. The CMC of the purified biosurfactant produced from T. montevideense CLOA72 is 2.2 mg/ml, as determined both by ITC dilution experiments and by surface tension measurements. This biomolecule did not presented any cytotoxic effect in HEK 293A cell line at concentrations of 0.25-1 mg/ml. This study suggests a possible application of the referred biosurfactant in inhibiting the formation of biofilms on plastic surfaces by C. albicans.

Novel rhamnolipid biosurfactants produced by a polycyclic aromatic hydrocarbon-degrading bacterium Pseudomonas aeruginosa strain NY3

A novel rhamnolipid biosurfactant-producing and Polycyclic Aromatic Hydrocarbon (PAH)-degrading bacterium Pseudomonas aeruginosa strain NY3 was isolated from petroleum-contaminated soil samples. Strain NY3 was characterized by its extraordinary capacity to produce structurally diverse rhamnolipids. A total of 25 rhamnolipid components and 37 different parent molecular ions, representing various metal ion adducts (Na(+), 2Na(+) and K(+)), were detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Among these compounds are ten new rhamnolipids. In addition to its biosurfactant production, strain NY3 was shown to be capable of efficient degradation of PAHs as well as synergistic improvement in the degradation of high molecular weight PAHs by its biosurfactant. These findings have added novel members to the rhamnolipid group and expanded current knowledge regarding the diversity and productive capability of rhamnolipid biosurfactants from a single specific strain with variation of only one carbon source. Additionally, this paper lays the foundation for improvement in the yield of NY3BS and study of the degradation pathway(s) of PAHs in P. aeruginosa strain NY3.