Management of soybean oil refinery wastes through recycling them for producing biosurfactant using Pseudomonas aeruginosa MR01

Glycolipids biosurfactants production using low-cost substrates for environmental remediation: progress, challenges, and future prospects

The production of renewable materials from alternative sources is becoming increasingly important to reduce the detrimental environmental effects of their non-renewable counterparts and natural resources, while making them more economical and sustainable. Chemical surfactants, which are highly toxic and non-biodegradable, are used in a wide range of industrial and environmental applications harming humans, animals, plants, and other entities. Chemical surfactants can be substituted with biosurfactants (BS), which are produced by microorganisms like bacteria, fungi, and yeast. They have excellent emulsifying, foaming, and dispersing properties, as well as excellent biodegradability, lower toxicity, and the ability to remain stable under severe conditions, making them useful for a variety of industrial and environmental applications. Despite these advantages, BS derived from conventional resources and precursors (such as edible oils and carbohydrates) are expensive, limiting large-scale production of BS. In addition, the use of unconventional substrates such as agro-industrial wastes lowers the BS productivity and drives up production costs. However, overcoming the barriers to commercial-scale production is critical to the widespread adoption of these products. Overcoming these challenges would not only promote the use of environmentally friendly surfactants but also contribute to sustainable waste management and reduce dependence on non-renewable resources. This study explores the efficient use of wastes and other low-cost substrates to produce glycolipids BS, identifies efficient substrates for commercial production, and recommends strategies to improve productivity and use BS in environmental remediation.

Microbe cultivation guidelines to optimize rhamnolipid applications

In the growing landscape of interest in natural surfactants, selecting the appropriate one for specific applications remains challenging. The extensive, yet often unsystematized, knowledge of microbial surfactants, predominantly represented by rhamnolipids (RLs), typically does not translate beyond the conditions presented in scientific publications. This limitation stems from the numerous variables and their interdependencies that characterize microbial surfactant production. We hypothesized that a computational recipe for biosynthesizing RLs with targeted applicational properties could be developed from existing literature and experimental data. We amassed literature data on RL biosynthesis and micellar solubilization and augmented it with our experimental results on the solubilization of triglycerides (TGs), a topic underrepresented in current literature. Utilizing this data, we constructed mathematical models that can predict RL characteristics and solubilization efficiency, represented as logPRL = f(carbon and nitrogen source, parameters of biosynthesis) and logMSR = f(solubilizate, rhamnolipid (e.g. logPRL), parameters of solubilization), respectively. The models, characterized by robust R2 values of respectively 0.581-0.997 and 0.804, enabled the ranking of descriptors based on their significance and impact-positive or negative-on the predicted values. These models have been translated into ready-to-use calculators, tools designed to streamline the selection process for identifying a biosurfactant optimally suited for intended applications.

Biotechnological Utilization of Agro-Industrial Residues and By-Products-Sustainable Production of Biosurfactants

The importance and interest in the efficient use and valorization of agro-industrial residues and by-products have grown due to environmental problems associated with improper disposal. Biotechnological production processes, including microbial biosurfactant production, represent a sustainable way to utilize agro-industrial residues and by-products, which are applied as substrates in these processes. Biosurfactants produced by microorganisms using renewable resources are a viable alternative to traditional petrochemical surfactants and have several potential uses in a wide range of industrial sectors due to their minimal ecotoxicity, easy biodegradability, and moderate production conditions. The common applications of biosurfactants, besides in food industry as food additives and preservatives, are in agriculture, environmental protection, the cosmetics and pharmaceutical industry, wastewater treatment, the petroleum industry, etc. This review aims to summarize the comprehensive scientific research related to the use of various agro-industrial residues and by-products in the microbial production of biosurfactants, as well as to emphasize the present state and the importance of their sustainable production. Additionally, based on the available biosurfactant market analysis datasets and research studies, the current situation in science and industry and the future perspectives of microbial biosurfactant production have been discussed.

An insight into the utilization of microbial biosurfactants pertaining to their industrial applications in the food sector

Microbial biosurfactants surpass synthetic alternatives due to their biodegradability, minimal toxicity, selective properties, and efficacy across a wide range of environmental conditions. Owing to their remarkable advantages, biosurfactants employability as effective emulsifiers and stabilizers, antimicrobial and antioxidant attributes, rendering them for integration into food preservation, processing, formulations, and packaging. The biosurfactants can also be derived from various types of food wastes. Biosurfactants are harnessed across multiple sectors within the food industry, ranging from condiments (mayonnaise) to baked goods (bread, muffins, loaves, cookies, and dough), and extending into the dairy industry (cheese, yogurt, and fermented milk). Additionally, their impact reaches the beverage industry, poultry feed, seafood products like tuna, as well as meat processing and instant foods, collectively redefining each sector's landscape. This review thoroughly explores the multifaceted utilization of biosurfactants within the food industry as emulsifiers, antimicrobial, antiadhesive, antibiofilm agents, shelf-life enhancers, texture modifiers, and foaming agents.

Kinetics and Production of Rhamnolipid from Pseudomonas sp. TMB2 in Shake-Flask and Fabricated Batch Reactor

Rhamnolipid producing Pseudomonas sp. TMB2 was selected for this investigation to optimize the metabolite production in fabricated batch reactor after studying yield kinetics in shake-flask and tried to reduce the overall production cost through In-situ recovery technology. Using various kinetic models, maximum specific growth rate (μmax) and half velocity constant (KS) of TMB2 were determined to be 0.185 ± 0.0025 h-1 and 0.124 ± 0.024 g/L in shake-flask, respectively. Further, a batch reactor was designed with integration of a foam fractionate column in the lid of the vessel and their performances were compared with shake-flask studies. The yields of rhamnolipids production on biomass (YP/X), rhamnolipids production on substrate (YP/S) and biomass production on substrate (YX/S) were found to be higher in reactor than that of shake-flask. The best conditions for maximum rhamnolipid production in reactor were observed to be 2 vvm and 300 rpm, giving YP/S = 0.152 g/g, YP/X = 0.542 g/g and YX/S = 0.280 g/g. Rhamnolipid production was increased by ≈ 10.18% in the reactor than that of shake-flask in optimized conditions. Rhamnolipid concentrations in the foamate were also found to be higher than that of reactor vessels. Further, the performance of foam fractionation was validated through enrichment and recovery, which were found in the range of 2.75-4.86 and 25.33-64.64%, respectively.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-022-01021-0.

Utilization of Soybean Oil Waste for a High-Level Production of Ceramide by a Novel Phospholipase C as an Environmentally Friendly Process

Ceramide is a natural functional ingredient as food additive and medicine that has attracted extensive attention in the food, medical, and cosmetic industries. Here, we developed a biotechnological strategy based on a recombinant whole-cell biocatalyst for efficiently producing ceramide from crude soybean oil sediment (CSOS) waste. A novel phospholipase C (PLC_ac) from Acinetobacter calcoaceticus isolated from soil samples was identified and characterized. Furthermore, recombinant Komagataella phaffii displaying PLC_ac (dPLC_ac) on the cell surface was constructed as a whole-cell biocatalyst with better thermostability (30-60 °C) and pH stability (8.0-10.0) to successfully produce ceramide. After synergistical optimization of reaction time and dPLC_ac dose, the ceramide yield of hydrolyzing from CSOS using dPLC_ac was 51% (the theoretical maximum yield of converting sphingomyelin, ∼70%) and the relative yield was over 50% after seven consecutive 4 h batches under the optimized conditions. Our study provides a potentially promising strategy for the commercial production of ceramide.

Valorization of Glycine max (Soybean) Seed Waste: Optimization of the Microwave-Assisted Extraction (MAE) and Characterization of Polyphenols from Soybean Meal Using Response Surface Methodology (RSM)

The present study aimed at determining the optimal conditions for extraction of total phenolic compounds from soybean (Glycine max) meal, a by-product of the soybean seeds industry, using a green protocol with microwave-assisted extraction (MAE). A face-centered composite design (FCCD) was used for optimization. Based on a screening aimed to determine the factors that significantly influenced the responses, a 50% hydro-ethanolic solution was used with solvent/dry matter ratio (60/1–110/1), power (120–270 W), and time (0–10 min) as factors, while the responses studied were total phenolic and flavonoid contents. FTIR, TLC, DPPH, and FRAP anti-oxidants tests were used to characterize the extracts obtained with optimum conditions. The factors that significantly influenced both responses were the individual effect of all factors, the interaction between solvent/dry matter ratio and extraction time, the quadratic effect of solvent/dry matter ratio, and power for total phenolic content, while only the quadratic effect of power significantly influenced the flavonoid content. The highest contents of phenols (13.09 mg GAE/g) and flavonoid (7.39 mg CE/g) were obtained at 120 W for 0.16 min with a solvent/dry matter ratio of 60/1. ATR-FTIR spectra indicated the presence of polyphenolic compounds in the extract, namely flavonoids. TLC indicated the presence of at least nine compounds in the extract, among which catechin and quercetin were identified with respective Rf of 0.98 and 0.93. DPPH assay showed the anti-oxidant capacity for the extract with an IC50 of 194.98 µg/ml. RSM permitted us to develop a green protocol for maximum extraction of polyphenols from soybean seeds waste using less solvent, low power, and a reduced time in MAE.

Bioreactor Rhamnolipid Production Using Palm Oil Agricultural Refinery By-Products

Palm fatty acid distillate (PFAD) and fatty acid methyl ester (FAME) are used by P. aeruginosa PAO1 to produce rhamnolipid biosurfactant. The process of fermentation producing of biosurfactant was structured in a 2 L bioreactor using 2% of PFAD and FAME as carbon sources in minimal medium and with a nitrogen concentration of 1 g L−1. Mass spectrometry results show the crude biosurfactant produced was predominantly monorhamnolipid (Rha-C10-C10) and dirhamnolipid (Rha-Rha-C10-C10) at 503 and 649 m/z value for both substrates. Maximum production of crude rhamnolipid for PFAD was 1.06 g L−1 whereas for FAME it was 2.1 g L−1, with a reduction in surface tension of Tris-HCl pH 8.0 solution to 28 mN m−1 and a critical micelle concentration (CMC) of 26 mg L−1 measured for both products. Furthermore, the 24 h emulsification indexes in kerosene, hexadecane, sunflower oil, and rapeseed oil using 1 g L−1 of crude rhamnolipid were in the range 20–50%. Consequently, PFAD and FAME, by-products from the agricultural refining of palm oil, may result in a product that has a higher added-value, rhamnolipid biosurfactant, in the process of integrated biorefinery.

Recent advancements in the production of rhamnolipid biosurfactants by Pseudomonas aeruginosa

Rhamnolipid (RL) biosurfactant which is produced by Pseudomonas species is one of the most effective surface-active agents investigated in the literature. Over the years, many efforts have been made and an array of techniques has been developed for the isolation of RL produced strains as well as RL homolog characterization. Reports show that RL productivity by the best-known producer, Pseudomonas aeruginosa, is very diverse, from less than 1 gr/l to more than 200 g L-1. There are some major parameters that can affect RL productivity. These are culture conditions, medium composition, the mode of operation (batch, fed-batch and continuous), bioengineering/gene manipulation and finally extraction methods. The present paper seeks to provide a comprehensive overview on the production of rhamnolipid biosurfactant by different species of Pseudomonas bacteria. In addition, we have extensively reviewed their potential for possible future applications.

Biotechnological Applications of Paenibacillus sp. D9 Lipopeptide Biosurfactant Produced in Low-cost Substrates

The present study assesses the Paenibacillus sp. D9 lipopeptide biosurfactant synthesis in cheap substrates including functional properties and applicability for varying biotechnological processes. Different experimental setups were made for oil dispersion, heavy metals removals from contaminated environments, and washing performance. The study revealed surface tension activities of 31.7-32.7 mN/m, and maximum biosurfactant yield of more than 8 g/L. Removals of 85.90%, 98.68%, 99.97%, 63.28%, 99.93%, and 94.22% were obtained for Ca, Cu, Fe, Mg, Ni, and Zn, respectively from acid mine effluents. In comparison with chemical surfactants, there was pronounced removal of heavy metals from wastewater, contaminated sands, and vegetable matter, as well as improved oil dispersing activity. A comparative study revealed that biosurfactant was more efficient (> 60%) for removal of tomato sauce and coffee stains than chemical surfactants (< 50%). Thus, lipopeptide biosurfactants are green biomolecules reducing hazards and contaminations within the environment. The future use of this lipopeptide biosurfactant is greatly promising in biotechnology.

Biosurfactant: A new frontier for greener technology and environmental sustainability

Petroleum hydrocarbons, oil, heavy metals pollution is becoming additional severe problem due to the growing call for crude oil and crude oil products related products in several fields of application. Such pollution have fascinated much considerations and attractions as it leads to ecological damages in both marines, aquatic and terrestrial ecosystems. Thus, different techniques including chemical surfactants and complex technologies have been proposed for their clean up from the environment, which in turn has detrimental effects on the environment. As of late, biosurfactant compounds have added much deliberation since they are considered as a reasonable option and eco-accommodating materials for remediation technology. The present society is confronting a few difficulties of usage, authorizing ecological protection and environmental change for the next generations. Biosurfactants hold the special property of minimizing and reducing the interfacial tension of liquids. Such features endure biosurfactants to afford a major part in emulsification, de-emulsification, biodegradability, foam formation, washing performance, surface activity, and detergent formulation, which have potential applications in the diverse industrial set-up. Conversations on cost-effective technologies, renewable materials, novel synthesis, downstream, upstream, emerging characterization techniques, molecular, and genetical engineering are substantial to produce biosurfactant of quality and quantity. Therefore, greater attention is being paid to biosurfactant production by identifying their environmental, and biotechnological applications. Be that as it may, the extravagant cost drew in with biosurfactants biotechnological synthesis and recovery can hamper their application in those areas. Notwithstanding these costs, biosurfactants can be used as these parts shows outstandingly high benefits that can at present beat the expenses incurred in the initial purification and downstream processes. Biosurfactant production by microorganisms is relatively considered one of the crucial know-how for improvement, growth, advancement, and environmental sustainability of the 21st century. There is a developing conversation around environmental safety and the significant role that biosurfactants will progressively play soon, for instance, the use of renewable by-products as substrates, potential reduction, re-use and recycling of waste and waste products. The review confers the usefulness of biosurfactants in the removal of environmental contaminants and, consequently, expanding environmental safety and drive towards greener technology.

Cytotoxic effects of mono- and di-rhamnolipids from Pseudomonas aeruginosa MR01 on MCF-7 human breast cancer cells

Rhamnolipids produced by P. aeruginosa MR01 were fractionated into mono- and di-rhamnolipids, and their dominant congeners, Rha-C₁₀-C₁₀ and Rha-Rha-C₁₀-C₁₀, were shown by mass spectrometry. Minimum surface tensions and critical micelle concentrations (CMC) were determined as "≃34 mN/m; ≃26.17 mg/l;" and "≃29 mN/m; ≃29.63 mg/l" for mono- and di-rhamnolipids, respectively. Spectrophotometry measurements provided a close approximation of CMC. Contact angle and diameter of wet area were determined for rhamnolipid-containing drops on hydrophobic paper to display their capability for alteration of surface wettability. Wet area measurement is a simple, reliable method not requiring a Drop Shape Analyzer. Cell viabilities determined by MTT assay showed a decline in a dose-dependent manner and estimated IC₅₀ values were 25.87 μg/ml and 31.00 μg/ml for mono- and di-rhamnolipids treating MCF-7 cells for 48 h. Morphological observations using the inverted phase-contrast microscopy and fluorescence microscopy via Hoechst staining revealed the apoptotic characteristics in treated MCF-7 cells. The semi-quantitative RT-PCR method demonstrated that expression of the p53 gene in mRNA levels significantly (P < 0.05) increased when treated with 30 μg/ml of each rhamnolipid compound for 12 h. It can be concluded that rhamnolipids derived from MR01 show significant anticancer potential against MCF-7 cell line and should be further investigated as natural, therapeutic anti-tumor agents.

Production of a Biosurfactant by Cunninghamella echinulata Using Renewable Substrates and Its Applications in Enhanced Oil Spill Recovery

This study aimed to evaluate the production of a surfactant by Cunninghamella echinulata, using agro-industrial residues, corn steep liquor (CSL), and soybean oil waste (SOW). The study had a factorial design, using as a variable response to the reduction of surface tension. C. echinulata was able to produce biosurfactant in assay, CSL (8.82%) and SOW (2%). The results showed that the biosurfactant was successfully produced by C. echinulata and had attractive properties, such as a low surface tension (31.7 mN/m), a yield of 5.18 g/L at 120 h of cultivation, and an anionic profile. It also achieved a reduction in surface tension stability in a wide range of pH values, temperatures, and salinity values. The biosurfactant produced by C. echinulata showed an absence of toxicity to Artemia salina. The influence of the biosurfactant on the viscosity of engine oil, burnt engine oil, diesel, soybean oil post-frying, canola oil, and water was investigated. The results reveal a mechanism for the decrease of the viscosity using hydrophobic substrates and the new biosurfactant solution at 1.5% of the (CMC). This enables the formulation of a low-cost culture medium alternative, based on corn steep liquor and the reuse of soybean oil after frying to produce a biosurfactant. Additionally, performance of the biosurfactant isolated from C. echinulata showed an excellent ability to remove spilled oil, such as diesel (98.7%) and kerosene (92.3%) from marine sand.

Optimization and characterization of biosurfactant production from kitchen waste oil using Pseudomonas aeruginosa

Kitchen waste oil (KWO) from catering industries or households was used as a low-cost carbon source for producing biosurfactants by self-isolated Pseudomonas aeruginosa. Fermentation performance with KWO was superior to those with four other carbon sources, with higher optical density (OD₆₀₀) of 2.33 and lower interfacial tension of 0.57 mN/m. Culture conditions for biosurfactant production were optimized, with optimal pH of 8.0 and nitrogen source concentration of 2.0 g/L, respectively. The results of infrared spectroscopy and liquid chromatography-mass spectrometry (LC-MS) showed that the biosurfactant was a mixture of six rhamnolipid congeners, among which Rha-Rha-C₁₀-C₁₀ and Rha-C₁₀-C₁₀ were the main components, with mass fraction of approximately 34.20 and 50.86%, respectively. The critical micelle concentration (CMC) obtained was 55.87 mg/L. In addition, the rhamnolipids exhibited excellent tolerance to temperature (20-100 °C), pH (6.0-12.0), and salinity (2-20%; w/v) in a wide range, thereby showing good stability to extreme environmental conditions. The rhamnolipids positively affected oil removal from oil sludge and KWO-contaminated cotton cloth, with removal rate of 34.13 and of 30.92%, respectively. Our results demonstrated that biosurfactant production from KWO was promising, with advantages of good performance, low cost and environmental safety.

Effect of Different Carbon Sources on Biosurfactants' Production by Three Strains of Lactobacillus spp

The potential of three indigenous bacterial strains (Lactobacillus delbrueckii N2, Lactobacillus cellobiosus TM1, and Lactobacillus plantarum G88) for the production of biosurfactants using sugar cane molasses or glycerol as substrates was investigated through emulsifying, surface tension, and antimicrobial activities. The different biosurfactants produced with molasses as substrate exhibited high surface tension reduction from 72 mN/m to values ranged from 47.50 ± 1.78 to 41.90 ± 0.79 mN/m and high emulsification index ranging from 49.89 ± 5.28 to 81.00 ± 1.14%. Whatever the Lactobacillus strain or the substrate used, the biosurfactants produced showed antimicrobial activities against Candida albicans LV1, some pathogenic and/or spoilage Gram-positive and Gram-negative bacteria. The yields of biosurfactants with molasses (2.43 ± 0.09 to 3.03 ± 0.09 g/L) or glycerol (2.32 ± 0.19 to 2.82 ± 0.05 g/L) were significantly (p < 0.05) high compared to those obtained with MRS broth as substrate (0.30 ± 0.02 to 0.51 ± 0.09 g/L). Preliminary characterization of crude biosurfactants reveals that they are mainly glycoproteins and glycolipids with molasses and glycerol as substrate, respectively. Therefore, sugar cane molasses or glycerol can effectively be used by Lactobacillus strains as low-cost substrates to increase their biosurfactants production.

Production of Bacillus amyloliquefaciens OG and its metabolites in renewable media: valorisation for biodiesel production and p-xylene decontamination

Biosurfactants are important in many areas; however, costs impede large-scale production. This work aimed to develop a global sustainable strategy for the production of biosurfactants by a novel strain of Bacillus amyloliquefaciens. Initially, Bacillus sp. strain 0G was renamed B. amyloliquefaciens subsp. plantarum (syn. Bacillus velezensis) after analysis of the gyrA and gyrB DNA sequences. Growth in modified Landy's medium produced 3 main recoverable metabolites: surfactin, fengycin, and acetoin, which promote plant growth. Cultivation was studied in the presence of renewable carbon (as glycerol) and nitrogen (as arginine) sources. While diverse kinetics of acetoin production were observed in different media, similar yields (6-8 g·L^-1) were obtained after 72 h of growth. Glycerol increased surfactin-specific production, while arginine increased the yields of surfactin and fengycin and increased biomass significantly. The specific production of fengycin increased ∼10 times, possibly due to a connecting pathway involving arginine and ornithine. Adding value to crude extracts and biomass, both were shown to be useful, respectively, for the removal of p-xylene from contaminated water and for biodiesel production, yielding ∼70 mg·g^-1 cells and glycerol, which could be recycled in novel media. This is the first study considering circular bioeconomy to lower the production costs of biosurfactants by valorisation of both microbial cells and their primary and secondary metabolites.

Utilization of Paneer Whey Waste for Cost-Effective Production of Rhamnolipid Biosurfactant

The present study aimed at isolating rhamnolipid biosurfactant-producing bacteria that could utilize paneer whey, an abundant waste source as sole medium for the production purpose. Pseudomonas aeruginosa strain, SR17, was isolated from hydrocarbon-contaminated soil that could efficiently utilize paneer whey for rhamnolipid production and reduce surface tension of the medium from 52 to 26.5 mN/m. The yield of biosurfactant obtained was 2.7 g/l, upgraded to 4.8 g/l when supplemented with 2 % glucose and mineral salts. Biochemical, FTIR, and LC-MS analysis revealed that extracted biosurfactant is a combination of both mono and di-rhamnolipid congeners. The critical micelle concentration (CMC) was measured to be 110 mg/l. Emulsification activity of the biosurfactant against n-hexadecane, olive oil, kerosene, diesel oil, engine oil, and crude oil were found to be 83, 88, 81, 92, 86, and 100 %, respectively. The rhamnolipid was detected to be non-toxic against mouse fibroblastic cell line L292.

Utilization of oleo-chemical industry by-products for biosurfactant production

Biosurfactants are the surface active compounds produced by micro-organisms. The eco-friendly and biodegradable nature of biosurfactants makes their usage more advantageous over chemical surfactants. Biosurfactants encompass the properties of dropping surface tension, stabilizing emulsions, promoting foaming and are usually non- toxic and biodegradable. Biosurfactants offer advantages over their synthetic counterparts in many applications ranging from environmental, food, and biomedical, cosmetic and pharmaceutical industries. The important environmental applications of biosurfactants include bioremediation and dispersion of oil spills, enhanced oil recovery and transfer of crude oil. The emphasis of present review shall be with reference to the commercial production, current developments and future perspectives of a variety of approaches of biosurfactant production from the micro-organisms isolated from various oil- contaminated sites and from the by-products of oleo-chemical industry wastes/ by-products viz. used edible oil, industrial residues, acid oil, deodorizer distillate, soap-stock etc.

Identification and characterization of biosurfactants produced by the Arctic bacterium Pseudomonas putida BD2

One hundred and thirty bacterial strains, isolated from Arctic soil on the Svalbard Archipelago, were screened for biosurfactant production. Among them, an isolate identified as Pseudomonas putida BD2 was selected as a potential biosurfactant-producer based on the surface/interfacial activity of the culture supernatant. The ability of the strain to produce simultaneously phosphatidylethanolamines and rhamnolipid, using glucose as a sole carbon source, was demonstrated. The rhamnolipid Rha-Rha-C10-C10 and two homologs of phosphatidylethanolamine were extracted from cell-free supernatant of P. putida BD2 culture with ethyl acetate and identified by UPLC-MS analysis. For Rha-Rha-C10-C10 the surface tension decreased from 72 to 31mN/m and the critical micelle concentration was 0.130mg/mL. The Rha-Rha-C10-C10 was able to form stable aggregates (80-121nm). Pretreatment of a polystyrene surface with 0.5mg/mL rhamnolipid inhibited bacterial adhesion by 43-79% and that of the pathogenic fungal species C. albicans by 89-90%. The same concentration of phosphatidylethanolamines inhibited bacterial adhesion by 23-72% and that of C. albicans by 96-98%. To our knowledge, this is the first report where one type rhamnolipid and two homologs of phospholipid biosurfactants were produced by P. putida isolated from Arctic soil.