A bacterial strain of Pseudomonas aeruginosa B0406 pathogen opportunistic, produce a biosurfactant with tolerance to changes of pH, salinity and temperature

Waste cooking oils as a sustainable feedstock for bio-based application: A systematic review

Waste cooking oils (WCOs) are common wastes and promising green, eco-friendly and sustainable feedstocks for bio-based applications. While the primary valorisation strategy revolves around the concept of waste-to energy, new research trends have emerged in the last decade. This systematic review provides a comprehensive analysis of the current state of the art in the conversion of WCOs into bio-based molecules. Based on the PRISMA methodology, 64 papers were selected using different databases and sources, such as: PubMed, ScienceDirect, Scopus and MDPI. The data extraction process focused on studies reporting the biological and chemical conversion of WCOs into value-added bioproducts. Many of the selected publications deal with the development of bioactive molecules, including biosurfactants, with application in pharmaceuticals, food, cosmetics, and bioremediation. Bioconversion processes mainly featured engineered Yarrowia lipolytica and Escherichia coli strains, even if additional microorganisms were also employed. In the same way, different chemical processes have been thoroughly studied. A smaller segment of research is directed to the production of feed supplements and soaps. Regulatory constraints limit further development in feed supplements due to potential contaminants, while soap production needs further stability studies. The present systematic review shows promising outcomes in the valorisation of WCOs through the development of value-added molecules and products. Despite the wide range of applications, these findings identify that the scalability and economic sustainability of the selected processes require further investigation. This study seeks to summarize the current state of the art and identify potential gaps to advance the industrialization of WCOs valorisation.

Exploring the potential of lactic acid bacteria and its molecular mechanism of action in the development of biosurfactants: Current finding and future outlook

Biosurfactants generated from lactic acid bacteria (LAB) offer an advantage over standard microbial surfactants due to their antifungal, antibacterial and antiviral capabilities. Many LAB strains have been related to the manufacture of biosurfactant, an essential chemical with uses in the treatment of a number of illnesses. Furthermore, their effectiveness as anti-adhesive agents against a diverse variety of pathogens proves their utility as anti-adhesive coating agents for medical insertional materials, reducing hospital infections without the need of synthetic drugs and chemicals. LAB produces both low and high molecular weight biosurfactants. Biosurfactants from L. pentosus, L. gasseri and L. jensenii have been reported to produce glycolipopeptides that comprise carbohydrates, proteins and lipids in the ratio of 1:3:6 with palmitic, stearic acid, and linoelaidic acid as the major fatty acid component, whereas L. plantarum has been reported to make surlactin due to the presence of non-ribosomal peptide synthetase genes (NRPS) genes. Antimicrobial activity of sophorolipids and rhamnolipids generated from LAB against B. subtilis, P. aeruginosa, S. epidermidis, Propionibacterium acnes and E. coli has been demonstrated. The safety of biosurfactants is being evaluated in compliance with a number of regulatory standards that emphasize the importance of safety in the pharmaceutical industry. This review attempts, for the first time, to provide a comprehensive evaluation of several approaches for the synthesis of biosurfactant-mediated molecular modulation in terms of their biological value. Future biosurfactant directions, as well as regulatory considerations that are crucial for the synthesis of biosurfactants from novel LAB, have also been explored.

High mono-rhamnolipids production by a novel isolate Pseudomonas aeruginosa LP20 from oily sludge: characterization, optimization, and potential application

This study aims to isolate microbial strains for producing mono-rhamnolipids with high proportion. Oily sludge is rich in petroleum and contains diverse biosurfactant-producing strains. A biosurfactant-producing strain LP20 was isolated from oily sludge, identified as Pseudomonas aeruginosa based on phylogenetic analysis of 16S rRNA. High-performance liquid chromatography-mass spectrometry results indicated that biosurfactants produced from LP20 were rhamnolipids, mainly containing Rha-C8-C10, Rha-C10-C10, Rha-Rha-C8-C10, Rha-Rha-C10-C10, Rha-C10-C12:1, and Rha-C10-C12. Interestingly, more mono-rhamnolipids were produced by strain LP20 with a relative abundance of 64.5%. Pseudomonas aeruginosa LP20 optimally produced rhamnolipids at a pH of 7.0 and a salinity of 0.1% using glycerol and nitrate. The culture medium for rhamnolipids by strain LP20 was optimized by response surface methodology. LP20 produced rhamnolipids up to 6.9 g L-1, increased by 116%. Rhamnolipids produced from LP20 decreased the water surface tension to 28.1 mN m-1 with a critical micelle concentration of 60 mg L-1. The produced rhamnolipids emulsified many hydrocarbons with EI24 values higher than 56% and showed antimicrobial activity against Staphylococcus aureus and Cladosporium sp. with inhibition rates 48.5% and 17.9%, respectively. Pseudomonas aeruginosa LP20 produced more proportion of mono-rhamnolipids, and the LP20 rhamnolipids exhibited favorable activities and promising potential in microbial-enhanced oil recovery, bioremediation, and agricultural biocontrol.

Bioremediation of environmental organic pollutants by Pseudomonas aeruginosa: Mechanisms, methods and challenges

The development of the chemical industry has led to a boom in daily consumption and convenience, but has also led to the release of large amounts of organic pollutants, such as petroleum hydrocarbons, plastics, pesticides, and dyes. These pollutants are often recalcitrant to degradation in the environment, whereby the most problematic compounds may even lead to carcinogenesis, teratogenesis and mutagenesis in animals and humans after accumulation in the food chain. Microbial degradation of organic pollutants is efficient and environmentally friendly, which is why it is considered an ideal method. Numerous studies have shown that Pseudomonas aeruginosa is a powerful platform for the remediation of environmental pollution with organic chemicals due to its diverse metabolic networks and its ability to secrete biosurfactants to make hydrophobic substrates more bioavailable, thereby facilitating degradation. In this paper, the mechanisms and methods of the bioremediation of environmental organic pollutants (EOPs) by P. aeruginosa are reviewed. The challenges of current studies are highlighted, and new strategies for future research are prospected. Metabolic pathways and critical enzymes must be further deciphered, which is significant for the construction of a bioremediation platform based on this powerful organism.

Potential of pineapple peel in the alternative composition of culture media for biosurfactant production

The large pineapple's consumption and processing have generated a massive amount of waste yearly, which requires adequate treatment measures to avoid damages to the environment. Pineapple peel is one of the main residues obtained from this fruit and a promising strategy to take advantage of its potential is using it for biosurfactant production due to the peel's rich composition in fermentable sugars and nutrients, such as potassium and magnesium that favor the Bacillus subtilis growth and biosurfactant excretion as well. The current research performed a central composite design (CCD) with four independent variables (glucose, pineapple peel, potassium, and magnesium), evaluating substrates' influence on the surface tension reduction rate (STRR) and the emulsification index (EI₂₄). The results indicated that pineapple peel has the necessary potential to act as a partial substitute for glucose and salt nutrients, minimizing the costs of supplementing with exogenous minerals. The highest surface tension reduction rate (57.744%) was obtained at 2.18% glucose (w/v); 14.67% pineapple peel (v/v); 2.38 g/L KH₂PO₄; and 0.15 g/L MgSO₄.7H₂O; whereas to obtain the maximum predicted value for EI₂₄ (61.92%) the medium was composed by 2.24% glucose (w/v); 12.63% pineapple peel (v/v); 2.53 g/L KH₂PO₄; and 0.29 g/L MgSO₄.7H₂O.

Planococcus Species - An Imminent Resource to Explore Biosurfactant and Bioactive Metabolites for Industrial Applications

The marine environment represents a well-off and diverse group of microbes, which offers an enormous natural bioactive compounds of commercial importance. These natural products have expanded rigorous awareness due to their widespread stability and functionality under harsh environmental conditions. The genus Planococcus is a halophilic bacterium known for the production of diverse secondary metabolites such as 2-acetamido-2-deoxy-α-d-glucopyranosyl-(1, 2)-β-d-fructofuranose exhibiting stabilizing effect and methyl glucosyl-3,4-dehydro-apo-8-lycopenoate displaying antioxidant activity. The genus Planococcus is reported generally for hydrocarbon degradation in comparison with biosurfactant/bioemulsifier secretion. Although Planococcus was proposed in 1894, it seized long stretch (till 1970) to get accommodated under the genus Planococcus authentically. Large-scale biosurfactant production from Planococcus was reported in 2014 with partial characterization. For the first time in 2019, we documented genomic and functional analysis of Planococcus sp. along with the physico-chemical properties of its biosurfactant. In 2020, again we screened biosurfactant for pharmacological applications. The present review discusses the comprehensive genomic insights and physical properties of Planococcus-derived biosurfactant. Moreover, we also highlight the prospects and challenges in biosurfactant production from Planococcus sp. Among ∼102 reports on biosurfactant produced by marine bacteria, 43 were of glycolipid and 59 were non-glycolipid type. Under other biosurfactant type, they were identified as lipopeptide (20) like surfactin (5), glycolipoprotein/lipoprotein (12), and other non-glycolipid (22). Planococcus sp. generally produces glycolipid-type biosurfactant (4) and exopolysaccharides (2). The single report documented in the literature is on biosurfactant production (glycolipid +non glycolipid) by diverse marine microbes (39) suggesting their novelty and diversity for biosurfactant secretion.