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Biosurfactants are in demand by the global market as natural commodities that can be added to commercial products or use in environmental applications. These biomolecules reduce the surface/interfacial tension between fluid phases and exhibit superior stability to chemical surfactants under different physico-chemical conditions. Biotechnological production of biosurfactants is still emerging. Fungi are promising producers of these molecules with unique chemical structures, such as sophorolipids, mannosylerythritol lipids, cellobiose lipids, xylolipids, polyol lipids and hydrophobins. In this review, we aimed to contextualize concepts related to fungal biosurfactant production and its application in industry and the environment. Concepts related to the thermodynamic and physico-chemical properties of biosurfactants are presented, which allows detailed analysis of their structural and application. Promising niches for isolating biosurfactant-producing fungi are presented, as well as screening methodologies are discussed. Finally, strategies related to process parameters and variables, simultaneous production, process optimization through statistical and genetic tools, downstream processing and some aspects of commercial products formulations are presented.

In this work, the application of chemical surfactants, including cooking aids, detergents, surface sizing agents, and deinking agents as core components, is introduced in the wet end of pulping and papermaking. This method for the combined application of enzymes and surfactants has expanded, promoting technological updates and improving the effect of surfactants in practical applications. Finally, the potential substitution of green surfactants for chemical surfactants is discussed. The source, classification, and natural functions of green surfactants are introduced, including plant extracts, biobased surfactants, fermentation products, and woody biomass. These green surfactants have advantages over their chemically synthesized counterparts, such as their low toxicity and biodegradability. This article reviews the latest developments in the application of surfactants in different paper industry processes and extends the methods of use. Additionally, the application potential of green surfactants in the field of papermaking is discussed. KEY POINTS: • Surfactants as important chemical additives in papermaking process are reviewed. • Deinking technologies by combined of surfactants and enzymes are reviewed. • Applications of green surfactant in papermaking industry are prospected.

The chemical surfactant-based synthesis route is the C-H-based aqueous method using to form the restrained shape of Cadmium Oxide (CdO) nanoparticles. The effect of different weight percentages of n-HEPTANE, POLYIMIDE, PVA, PVP, SDS in the preparation of CdO nanoparticles is studied. The surfactants are highly influenced by particle size variation and morphology gets changed. The role of surfactant is not produced any structural change apart from the particle size which is the advantageous part of the surfactant-based synthesis. The particle sizes from X-ray diffraction (XRD) analysis were found that there is a decrease in particle size from 54 to 92 nm when using the artificial chemical additives. The firmness of the CdO nanoparticles synthesized with help of chemical surfactants was characterized by UV-vis Diffused Reflectance Spectrometer (DRS), Fourier Transformer inferred (FT-IR), and photoluminescence studies. The photocatalytic activity and antimicrobial activity is investigated on using the chemical surfactant-based CdO nanoparticles as catalyst under Solar irradiation and zone inhibition method respectively.

Biological surface-active compounds (biosurfactants) are commonly used in many industries (cosmetics, food, agriculture, oil, petrochemicals, etc.). The ability of biosurfactants to reduce the interfacial tensions between two liquid phases is a crucial property that makes them useful in separating oil from water or water from oil. Biosurfactants help to separate the two phases by changing the interfacial forces between oil and water molecules. Biosurfactants are biomolecules generated by microorganisms. They are nontoxic or less toxic than chemical surfactants. They are typically classified based on their chemical compound and microbial origin. There are several recognized biosurfactants in the literature that may be used for this function, including sophorolipids, glycolipid, trehalolipids, rhamnolipids, lipopeptides and lipoproteins, surfactin, lichenysin, and polymeric biosurfactants. This chapter aims to review different types of biosurfactants, their properties, their synthesis methods from different microorganisms (e.g., bacteria and fungi), and their role in demulsification process of water from oil. Eventually, the impact of various parameters on the biodemulsification process was reviewed, which include type of microorganisms, temperature, pH, the water content in the emulsion, and gravity effect.

Microbial surfactants exhibit various advantages over synthetic or chemical surfactants. BSs are regarded to be “green” substitutes to surfactants of chemical origin. Microbial surface-active agents, which exhibit significant surface properties, are considered as “greener surfactants.” The majority of the surfactants now available in the market for industrial and environmental applications are chemically synthesized. In the last decade, consideration toward the BSs has been raised, which is primarily due to their extensive range of functional characteristics and the diverse production potential of the producing organism. There is an emerging need for the sighting of new non-pathogenic strains with maximal production potential and exertions to commercialize through efficient downstream processing are vital to meet the future forecasts of BSs market size. Biodegradability is recognized as a vital feature, exclusion of these amphiphiles from environmental sites, and, henceforth, degradability is regarded as an important property when estimating the environmental hazard linked with surfactant use. Regarding a solo approach for comparing BSs and chemical surfactants, would not be appropriate as no one tactic would consistently measure characteristics, usage, and disposal. Furthermore, the reply to this present situation hinges on what we mean by “efficiency.” For any surface-active agent “efficiency” can be demarcated in different ways, i.e. critical micelle concentration, surface tension, and emulsification potential (the lower the concentration, the improved the surfactants), decrease in air-water surface tension, emulsification (how efficiently they stabilize two different mixtures with diverse surface tension). Even though BSs have been considered as a promising substitute for synthetic surfactants for years, but they still need to deliver on their efficacy on various fronts. It is hopeful to see that there is still abundant space is available for basic research of the molecular interactions of their surface potential, and it will be a huge step frontward to be able to fit this information into a better inclusive considerate of the interactions among microorganisms and their applications in biosurfactants applications as a greener sustainable agents.

Wastewater and water pollution have caused serious concern around the world and many have attempted to propose sustainable remediation methods. Among many physical, chemical and biological techniques proposed for wastewater remediation and management, it is fair to suggest that biosurfactants might be a candidate as a promising solution. Biosurfactants, biologically produced amphiphilic surfactants, have garnered much attention during the last decade, and many scholars have investigated various experiments to pave the way for large production of biosurfactants in industries. Low toxicity, safety, acceptable efficiency, and bioavailability are some of the main advantages of biosurfactants. This chapter introduces biosurfactants as a sustainable bioremediation method. Factors affecting biosurfactant production including carbon and nitrogen are investigated. In addition, biosurfactants classification and chemical surfactants are discussed.

Biosurfactants are molecules derived from microorganisms, possessing both hydrophilic and hydrophobic ends. Because of these distinct characteristics, biosurfactants have attracted great attention for wide use in industrial and commercial applications. The advantages of biosurfactants over chemical surfactants include lesser toxicity, and environmental, and ecofriendliness. However, despite the vast potential, there have been limited industrial productions of biosurfactants, as there are challenges to meet the economic expectation. In this review, the diverse types of biosurfactants, the microbial sources and origin, industrial applications, and the mass production in the bioreactor systems and operations are discussed. Various factors and parameters influencing the yield, productivity, and quality, including the high-producing strains, nutritional and environmental factors, bioreactor configuration, mode of operation, and parameter optimization, are elaborated.

Bio-based rhamnolipid production from waste streams is gaining momentum nowadays because of increasing market demand, huge range of applications and its economic and environment friendly nature. Rhamnolipid type biosurfactants are produced by microorganisms as secondary metabolites and have been used to reduce surface/interfacial tension between two different phases. Biosurfactants have been reported to be used as an alternative to chemical surfactants.Pseudomonas sp.has been frequently used for production of rhamnolipid. Various wastes can be used in production of rhamnolipid. Rhamnolipids are widely used in various industrial applications. The present review provides information about structure and nature of rhamnolipid, production using different waste materials and scale-up of rhamnolipid production. It also provides comprehensive literature on various industrial applications along with perspectives and challenges in this research area., Authors are grateful to the management of Gujarat Pollution Control Board, Gandhinagar, Gujarat, India for providing necessary facilities to perform literature review presented in this paper., info:eu-repo/semantics/publishedVersion

Surfactants such as lecithin and egg yolk have been known for decades for their usefulness in the food systems. High toxicity and environmental influence of various surfactants have led to attention in other, natural surface-active agents such as microbial surfactants. The rising demand for surfactants in the food system also upsurges the consumer expectancy of non-toxic “green label” molecules over chemical surfactants. Sophorolipids and other established biosurfactants from Generally Regarded as Safe organisms have huge potential in the food system with an advantage of no acute toxicity. The major bottleneck is not the establishment of the cost-effective process but the apprehension about their safety and possible microbial hazards. Most of the research about biosurfactants in the food system are only limited to the applications, without doing an assessment of safety and risk analysis, and it is one of the undermined reasons behind the adoption of biosurfactants for food application. It should be consider for the appropriate applications such as biosurfactants with high HLB value must be used as food emulsifiers whereas, antimicrobial potential can be achieved at low concentrations and synergies with other conventional food preservatives. The efficacy of surfactin, rhamnolipids, and sophorolipids is evidenced to be utilized in bakery products with improved texture, properties, and food quality. The present book chapter emphases the most promising properties of biosurfactants, current use in food formulations, risk, and toxicity assessment, and forthcoming biosurfactants to substitute the currently used surfactants will be assessed.

This chapter focuses on the role of biosurfactants in the remediation of petroleum hydrocarbon by microbes over chemical surfactants. An emphasis has also been placed on the common types, properties, and characteristics of biosurfactants involved in hydrocarbon bioremediation. The potential microbes involved in the cleanup of hydrocarbon-contaminated environments with biosurfactant synthesis are also addressed. The aim is also to introduce the constraints and challenges of biosurfactant production and its use in hydrocarbon remediation. The recent advances in biosurfactant production processes are also elaborated. The strategies for improvement in production of natural surfactants by microbes, cost-effectiveness, and the commercialization of biosurfactants for petroleum hydrocarbon are also emphasized.

Microorganisms produce a variety of secondary metabolites such as antibiotics, biosurfactants, pigments, toxins, alkaloids, and carotenoids. Among these, biosurfactants are unique as they are not ribosomally encoded, and most importantly, they furnish a wide range of attributes such as increased stability at extremes of conditions and growth on hydrocarbons to the producing organism. Environmental concerns and emergence of new stringent laws had led to the search for biosurfactants as a potential alternative to their chemical counterparts. Biosurfactants are primarily bioactive molecules that are amphiphilic in nature and work at air-water and oil-water interfaces. They offer several advantages over chemical surfactants such as low toxicity, easy biodegradability, and high specificity. These molecules are encoded by a number of genes regulating their synthesis, viz., rhamnolipids are encoded by rhamnosyltransferase genes (rhlABC), sophorolipids by glucose-dependent transferases (ugtB1 and ugtA1), and surfactins by srf and sfp genes. They are commercially produced by utilizing various wastes or by-products generated from industrial sources, thus contributing toward circular bioeconomy. These biosurfactants offer several applications in diverse fields and can be used as an environmental agent for bioremediation, microbial enhanced oil recovery, metal removal, pesticides, food additives, a component in cosmetic products, and therapeutics in medicine. Thus, the ecofriendly microbial biosurfactants produced by utilizing various wastes can be commercially employed, strengthening the concept of circular bioeconomy for sustainable growth and development.

Cosmetic and personal care products are globally used and often applied directly on the human skin. According to a recent survey in Europe, the market value of cosmetic and personal care products in Western Europe reached about 84 billion euros in 2018 and are predicted to increase by approximately 6% by the end of 2020. With these significant sums of money spent annually on cosmetic and personal care products, along with chemical surfactants being the main ingredient in a number of their formulations, of which many have been reported to have the potential to cause detrimental effects such as allergic reactions and skin irritations to the human skin; hence, the need for the replacement of chemical surfactants with other compounds that would have less or no negative effects on skin health. Biosurfactants (surfactants of biological origin) have exhibited great potential such as lower toxicity, skin compatibility, protection and surface moisturizing effects which are key components for an effective skincare routine. This review discusses the antimicrobial, skin surface moisturizing and low toxicity properties of glycolipid and lipopeptide biosurfactants which could make them suitable substitutes for chemical surfactants in current cosmetic and personal skincare pharmaceutical formulations. Finally, we discuss some challenges and possible solutions for biosurfactant applications.

The application of microbial biosurfactants in environmental technologies is gaining interest due to growing environmental concerns. Recently, immense attention is given to the environmental issues caused by synthetic surfactants owing to their toxicity and complexity in being decomposed in the environment. Microbial biosurfactants are promising because of their biodegradability, low toxicity, and efficacy in increasing biodegradation and solubilization of insoluble compounds at extreme environmental conditions. These molecules are impending substitutes for chemical surfactants in various industrial and environmental applications, such as lubrication, wetting, softening, emulsion forming, stabilization of dispersions, anti-foaming, enhanced oil recovery, as well as bioremediation of oil, heavy metals, pesticides, and organic/inorganic contaminants. The current review emphasizes a comprehensive overview on the environmental applications of biosurfactants and their role in various environmental processes.

Graphical abstract, Highlights • Soaps and hand sanitizers are used for hand hygiene and are on high demand during COVID-19 pandemic. • Petrochemical based surfactants and alcohols are hazardous to human and environment. • Biosurfactants and plant secondary metabolites could be used as ecofriendly hand hygiene., The Coronavirus disease-2019 (COVID-19) outbreak is caused by a highly pathogenic novel coronavirus (SARS-CoV-2). To date, there is no prescribed medicine for COVID-19. Frequent handwashing with soap and the use of alcohol-based hand sanitizers is recommended by WHO for hand hygiene and to prevent the spread of COVID-19. However, there are safety concerns associated with the use of soaps and alcohol-based hand sanitizers. Therefore, the review aims to highlight the health and environmental concerns associated with the frequent use of soaps/detergents and alcohol-based hand sanitizers amid COVID-19. The potential of some of the natural detergents and sanitizing agents as eco-friendly alternatives to petrochemical-based soaps and alcohol-based hand rubs for hand hygiene are discussed. The market of soaps and hand sanitizers is expected to grow in the coming years and therefore, future research should be directed to develop eco-friendly soaps and hand sanitizers for human and environmental safety.

Studies addressing for ecological compatible products have been increased along time, especially, on biosurfactant field. Biosurfactants are extracellular amphiphilic compound that are mainly produced by microorganisms and are classified into five main groups, including the glycolipids one. Rhamnolipids are included in the latter and are anionic biosurfactants produced predominantly by Pseudomonas aeruginosa being classified as mono- and di-rhamnolipids. In addition, their production may occur from different carbon sources, which may be obtained from renewable and low-cost residue. Therefore, it is possible to reduce the rhamnolipids production cost, since this has been the main bottleneck for replacing the chemical surfactants. In addition, to meeting a bona fide industrial application some limitations such as low productivity as well as recovery and/or purification that represent from 60 to 80% of total production cost should be improved. Therefore, this review covers different ways for producing rhamnolipids covering their application in many fields such as pharmaceutical, agricultural, petrochemical and so on; demonstrating the versatility of these biological compounds.

A significant synergistic effect has been reported between microbial cultures and chemical surfactants in crude oil recovery processes. A number of attempts have been made to understand the synergistic mechanism. However, the existing studies only addressed the aspects of wettability alteration and interfacial tension (IFT) reduction, although there are many more contributors to the mechanism, such as emulsification, functional microbial activities, and diverse byproducts. In addition, the previous knowledge on synergistic oil recovery was based on indirect evidence from core-scale flooding and test tube experiments. To fully exploit the synergistic effects in the future, a new experimental system must be introduced (i) to verify the existing mechanisms in situ in porous media during the flooding process and (ii) to address the other potential contributors for a more comprehensive insight into the actual major contributors. Therefore, a visual pore-scale flooding experimental system was introduced in the ...

Surfactants and emulsifiers are surface-active compounds (SACs) which play an important role in various industrial processes and products due to their interfacial properties. Many of the chemical surfactants in use today are produced from non-renewable petrochemical feedstocks, while biosurfactants (BS) produced by microorganisms from renewable feedstocks are considered viable alternatives to petroleum based surfactants, due to their biodegradability and eco-friendly nature. However, some well-characterised BS producers are pathogenic and therefore, not appropriate for scaled-up production. Marine-derived BS have been found to be produced by non-pathogenic organisms making them attractive possibilities for exploitation in commercial products. Additionally, BS produced from marine bacteria may show excellent activity at extreme conditions (temperature, pH and salinity). Despite being non-pathogenic, marine-derived BS have not been exploited commercially due to their low yields, insufficient structural elucidation and uncharacterised genes. Therefore, optimization of BS production conditions in marine bacteria, characterization of the compounds produced as well as the genes involved in the biosynthesis are necessary to improve cost-efficiency and realise the industrial demands of SACs.

Biosurfactants are biologically produced by microorganisms and therefore biodegradable, making ideal substitutes to chemical surfactants for various applications. Large scale production of ...

Nanoparticles (NPs) have a momentous role in disease healing and drug delivery system that leads to the development of a new field known as nanopharmacology. Nanoparticles are generally coated with polymers, metal ions, chemical surfactants, etc., owing to their properties, i.e., with the decrease in size they tend to evoke toxicity that is predominantly triggered by the environmental and human health risk. Therefore, it is imperative to evaluate the toxicity of nanoparticles using model systems. The purpose of the present chapter is to estimate the toxicity of nanoparticles against brine shrimp (Artemia). They are the essential part in the process of energy discharge of the food web in aquatic surroundings. Latterly, researchers have focal point on brine shrimp due to their accessibility, inexpensive and expeditious screening procedure. It is convenient to exemplify the toxicological impacts of nanoparticles toward brine shrimp, their mechanism, strategy and future prospective. The toxicity assay of NPs in Artemia are of low cost, continuously accessible, simple and steady. Researchers employed various types of nanoparticles to elucidate the toxicity and safety effects on brine shrimps. The green methods of synthesis have been attracted by scientists due to its low cost, ease of characterisation and capability to reduce NPs toxicity. In addition, researchers also used brine shrimp toxicity assay to evaluate the lethal effect of chemically synthesized nanoparticles. It also discusses the toxicological evaluation of NPs by in vitro and in vivo assessment and brief details on biology of brine shrimp.

Surface active agents are characterized for their capacity to adsorb to fluid and solid-water interfaces. They can be classified as surfactants and emulsifiers based on their molecular weight (MW) and properties. Over the years, the chemical surfactant industry has been rapidly increasing to meet consumer demands. Consequently, such a boost has led to the search for more sustainable and biodegradable alternatives, as chemical surfactants are non-biodegradable, thus causing an adverse effect on the environment. To these ends, many microbial and/or marine-derived molecules have been shown to possess various biological properties that could allow manufacturers to make additional health-promoting claims for their products. Our aim, in this review article, is to provide up to date information of critical health-promoting properties of these molecules and their use in blue-based biotechnology (i.e., biotechnology using aquatic organisms) with a focus on food, cosmetic and pharmaceutical/biomedical applications.

Sophorolipids (SLs), mainly synthesized by yeasts, were a sort of biosurfactant with the highest fermentation level at present. In recent years, SLs have drawn extensive attention for their excellent physiochemical properties and physiological activities. Besides, issues such as economics, sustainability, and use of renewable resources also stimulate the shift from chemical surfactants towards green or microbial-derived biosurfactants. SLs’ large-scale production and application were restricted by the relatively high production costs. Currently, waste streams from agriculture, food and oil refining industries, etc., have been exploited as low-cost renewable substrates for SL production. Advanced cultivation method, uncommonly used substrates, and new genetically modified SL-producing mutants were also designed and applied to improve the productivity or the special properties of SLs. In this review, a systematic and detailed description of primary and secondary metabolism pathways involved in SL biosynthesis was summarized firstly. Furthermore, based on the pathways of SL biosynthesis from different carbon substrates, we reviewed the current knowledge and advances in the exploration of cost-effective and infrequently used hydrophilic and hydrophobic substrates for large or specialized SL production.

Emulsification is one of the proposed mechanisms for enhancing crude oil recovery in chemical flooding. The replacement of chemical surfactants in enhanced oil recovery (EOR) applications with biosurfactants is an attractive alternative; yet, there is a lack of studies on the crude oil emulsification using biosurfactants. Particularly, the formulation of crude oil/water (crude O/W) nanoemulsions with an extreme stability and a pH-responsiveness behavior is still not documented in the literature, to the best of our knowledge. Accordingly, we report in this study the preparation of both light and heavy crude oil/water emulsions using different concentrations of the rhamnolipid biosurfactant. The emulsions were prepared in a two-step process: stirring overnight to create coarse emulsions followed by sonication. All the prepared emulsions have a nanoscale size (e.g., about 50% of the formed droplets at 0.1 wt% rhamnolipid are

This article includes an updated review of the classification, uses and side effects of surfactants for their application in the cosmetic, personal care and pharmaceutical industries. Based on their origin and composition, surfactants can be divided into three different categories: (i) synthetic surfactants; (ii) bio-based surfactants; and (iii) microbial biosurfactants. The first group is the most widespread and cost-effective. It is composed of surfactants, which are synthetically produced, using non-renewable sources, with a final structure that is different from the natural components of living cells. The second category comprises surfactants of intermediate biocompatibility, usually produced by chemical synthesis but integrating fats, sugars or amino acids obtained from renewable sources into their structure. Finally, the third group of surfactants, designated as microbial biosurfactants, are considered the most biocompatible and eco-friendly, as they are produced by living cells, mostly bacteria and yeasts, without the intermediation of organic synthesis. Based on the information included in this review it would be interesting for cosmetic, personal care and pharmaceutical industries to consider microbial biosurfactants as a group apart from surfactants, needing specific regulations, as they are less toxic and more biocompatible than chemical surfactants having formulations that are more biocompatible and greener. Xunta de Galicia | Ref. GPC-ED431B 2020/17 Ministerio de Economía, Industria y Competitividad (España) | Ref. IJCI-2016-27445 Ministerio de Educación, Cultura y Deporte (España) | Ref. FPU15 / 00205 Universidade de Vigo | Ref. beca predoctoral

Microbial growth and biofilms formation are a continuous source of contamination on most surfaces with biological, inanimate, natural or man-made. The use of chemical surfactants in daily practice to control growth, presence or adhesion of microorganisms and ultimately the formation of biofilms and biofouling is therefore becoming essential. Synthetic surfactants are, however, not preferred or ideal and biologically derived surface active biosurfactants (BSs) molecules produced mainly by microorganisms are therefore becoming attractive and sought by many industries. The search for innovative and interesting BS molecules that have effective antimicrobial activities and to use as innovative alternatives to chemical surfactants with added antimicrobial value among many other advantages has been ongoing for some time. This review discusses the various roles of BS molecules in association with biofilm formation. Recent updates on several mechanisms involved in biofilm development and control are presented vide this article.

This chapter focuses on the future prospects for research and exploitation of microbial biosurfactants and deals with some of the key areas that will need to be addressed. First, the production and cost of the final product is identified as a key driver for future commercial exploitation, where the products will be in direct competition with existing chemical surfactants derived from non-renewable resources. Although the surfactant activity of these compounds has been a primary focus of attention, it is now becoming clear that they have important bioactivities, such as antimicrobial and anticancer properties, which will enhance their value in consumer products. The identification of new producer organisms and the genetic manipulation of existing known producers are also identified as important areas for continuing research. Finally, the impact and application of microbial biosurfactants in the environment is discussed.

Owing to their versatile properties, many biosurfactants are implicated in the cleanup of oil spills, heavy metals, and organopollutants. A number of biosurfactants have the potential to be used in the household detergent formulation as they are good stain remover and are quite compatible with enzymes and other additives used in detergents. This chapter presents an in-depth evaluation of the use of biosurfactants in bioremediation and in approaches for maintaining soil quality. However, many studies on the exogenous supplementation of biosurfactants in bioremediation showed the contradictory effect on biodegradation of pollutants. Hence, a thorough investigation of the efficacy and toxicity of biosurfactants is to be performed before implementing the biosurfactants in bioremediation. Biosurfactants can be a potential replacement to chemical surfactants only if they meet the large-scale production and cheap prices of synthetic surfactants. Use of inexpensive substrates, employing high yield strain, and developing cost-effective downstream processing are some of the approaches to reduce the cost of biosurfactants.

Biosurfactants are surface-active molecules which are produced by the wide range of microbes including bacteria, fungi, and yeast. They have several advantages over the chemical surfactants such as higher biodegradability, lower toxicity, better environmental compatibility, high selectivity, higher foaming, and specific activity under extreme conditions such as temperature, pH, and salinity. All the surfactants now accessible in the market are synthetically orchestrated. As of late, consideration toward the biosurfactants was multiplied, which is basically because of their extensive variety of utilitarian properties and the assorted manufactured abilities of the microorganisms. Microbial biosurfactants are found to have an extensive variety of utilizations in ecological security, which incorporate upgrading oil recuperation, controlling oil slicks, biodegradation, and detoxification of oil-debased modern effluents and soils. Biosurfactants delivered by microorganisms have potential applications in pharmaceutical/solution, sustenance, corrective, pesticide, oil, and biodegradation ventures. In this survey article, we focused on three vital angles, for example, different sorts of biosurfactants, the gathering of microorganisms engaged with the generation of biosurfactants, and utilization of microbial biosurfactants.

The growing industrial development and concomitant efforts to protect mother Earth from alleviating pollution levels has greatly demanded the use and disposal of milder chemicals and xenobiotics. Of the widely used xenobiotics, surfactants have an increasing market demand due to its prevalent role in pharmaceutical preparations, food industry as well as almost all foaming products. The use of biosurfactants in place of chemical surfactants has gained momentum owing to the low toxicity, higher biodegradability and better environmental compatibility of biosurfactants. The current review outlays the various biosurfactants produced and their significance in various industries. An outline of the various biosynthetic pathways, challenges and advancements in the synthesis of the two mostly used biologically synthesised biosurfactants—rhamnolipids and sophorolipids has been discussed.

This chapter focuses on different applications of biosurfactants in microbial enhanced oil recovery, bioremediation, medicine, food, pharmaceutical and agriculture industries. Biosurfactants can be broadly grouped into two categories namely low and high molecular weight biosurfactants. In many cases, environmental contamination caused by industrial activity is due to accidental or deliberate release of organic and/or inorganic compounds into the environment. Biosurfactants have been explored for their bioremediation potential, and show promise for application to sites impacted by both organic and metal contaminants. Biosurfactants used in agriculture are also referred as green surfactants. Lipopeptide biosurfactants are made up of lipids and peptides. The increasing demand of consumers for use of natural compounds in food in place of chemicals has drawn attention of many towards research in the paddy soil field. Biosurfactants gain importance as they are biodegradable and lower toxic then chemical surfactants.

Biosurfactants (BSs) are a class of secondary metabolites representing a wide variety of structures that can be produced from renewable feedstock by a wide variety of micro-organisms. They have (potential) applications in the medical world, personal care sector, mining processes, food industry, cosmetics, crop protection, pharmaceuticals, bio-remediation, household detergents, paper and pulp industry, textiles, paint industries, etc. Especially glycolipid BSs like sophorolipids (SLs), rhamnolipids (RLs), mannosylerythritol lipids (MELs) and cellobioselipids (CBLs) have been described to provide significant opportunities to (partially) replace chemical surfactants. The major two factors currently limiting the penetration of BSs into the market are firstly the limited structural variety and secondly the rather high production price linked with the productivity. One of the keys to resolve the above mentioned bottlenecks can be found in the genetic engineering of natural producers. This could not only result in more efficient (economical) recombinant producers, but also in a diversification of the spectrum of available BSs as such resolving both limiting factors at once. Unraveling the genetics behind the biosynthesis of these interesting biological compounds is indispensable for the tinkering, fine tuning and rearrangement of these biological pathways with the aim of obtaining higher yields and a more extensive structural variety. Therefore, this review focuses on recent developments in the investigation of the biosynthesis, genetics and regulation of some important members of the family of the eukaryotic glycolipid BSs (MELs, CBLs and SLs). Moreover, recent biotechnological achievements and the industrial potential of engineered strains are discussed.

Biosurfactants are surface-active molecule produced by microorganisms and have several advantages over the chemical surfactants. The objective of this research was to obtain biosurfactant-producing bacteria from hydrocarbon contaminated soils in Jakarta Bay and to observe their biosurfactant activity through emulsification capacity and surface tension reduction capability. Overall, 19 isolates were screened for biosurfactant production by hemolysis assay, drop collapse assay and oil spreading assay. The result showed that 13 strains gave positive results on the screening tests and were determined as biosurfactant-producing bacteria. Three strains (TKY 3, TKY 14 and TKY 19) had the best biosurfactant activity. The lowest surface tension value was achieved by two strains (TKY 19 and TKY 14) with the same value of 37,84±1,45 mN/m.

This study reports the analysis of biosurfactant production by a bacterial consortium culture (CC) during biodegradation of crude oil. The ability of CC (5% v/v), grown in Minimal Medium (MM) added with 1% (v/v) Tapis crude oil, to produce biosurfactant under different incubation times (0, 2, 4, 6 and 8 week) was investigated. Biosurfactant activity was estimated by water surface tension changes and emulsification index (E24). Maximum biosurfactant production was observed at 2 weeks incubation period, after which the yield gradually decreased. The biosurfactant produced by the CC significantly decreased the surface tension of water from 72 dynes/cm to 52 dynes/cm (p < 0.05) at week 4. Emulsification test indicated that this biosurfactant effectively emulsified the crude oil with an emulsification index (E24) of 85% (p < 0.05). This is significantly better (p < 0.05) when compared to other chemical surfactants tested namely SDS (53.3%), Tween-20 (50.8%) and Triton X-100 (55%). These results indicate the capability of CC to produce biosurfactant during crude oil degradation and this can be exploited for enhanced bioremediation in oil contaminated areas.

Water solubilities of anthracene and phenanthrene were measured by adding a plant-derived biosurfactant Saponin and/or synthetic surfactants correspondingly below and above their critical micelle concentrations (CMCs). The results showed that the solubilities of anthracene and phenanthrene in water were greatly enhanced following a linear fashion if adding Saponin, TX100 and Brij35, respectively. The enhancing solubility capacities for Polycyclic aromatic hydrocarbons (PAHs) followed the order as: Saponin > Brij35 > TX100 at the concentrations below their CMC. It also proved that biosurfactant Saponin exhibited much higher enhancement efficiency for PAHs solubilization than the synthetic ones at the concentrations below the CMC. However, the solubility enhancement efficiencies of surfactants above the CMC turned to be the following order as Brij35 > Saponin > TX100. Furthermore, this study has confirmed that PAHs are synergistically solubilized in the mixed biologic-synthetic surfactant solutions, especia...

During the 1960s, the science of biosurfactants was in its infancy and received attention mainly as hydrocarbon dissolving agents. Recently biosurfactants have emerged as the most versatile product of the modern microbial biotechnology. Owing to its biodegradable nature, it has been considered as “green chemical.” Recently, increasing awareness toward sustainable ecosystem and environmental protection has resulted in a concerted research in biosurfactant as a promising substitute of chemical surfactants. It can be produced from nonrenewable resources, with alternative synthesis from economical renewable feedstocks. Apart from the stability at relatively adverse environments, these compounds are readily biodegradable in the environment. Functional properties of these compounds are being conferred by their structural diversity which varies among the microbial community. These compounds may provide advantages in a particular ecological niche or may be responsible for the niche-specific behavior of the producer microorganism. Diverse properties encompassed by biosurfactants are wetting, dispersion, emulsification, foaming, cleansing, phase separation, reduction in viscosity, and surface activity. It serves a broad spectrum of industries like petroleum, paint, paper, textile, leather, agriculture, cosmetic, food processing, agriculture, and pharmaceutical industries, thereby plays a significant role in white biotechnology.

Industrial sustainability has pushed biosurfactants as a tool for many companies. Biosurfactants offer possibility of replacing chemical surfactants, produced from nonrenewable resources and/or cheap renewable feedstocks. Biosurfactants are also attractive as they are ecofriendly. The most promising biosurfactants nowadays are glycolipids, lipopeptides, phospholipids, fatty acids/natural lipids, polymeric surfactants, and particulate biosurfactants. Biosurfactants find utility in various industrial sectors such as petroleum, food, beverage, cosmetics, detergents, pharmaceuticals, and environmental protection and management. This chapter highlights prospects for commercial exploration of a new generation microbial biosurfactants as a tool in bioremediation and microbial enhanced oil recovery (MEOR).

Several biological processes in prokaryotic and eukaryotic organisms require the presence of glycolipids (biosurfactants), compounds with both hydrophilic and hydrophobic groups in their structure. They constitute the backbone of different metabolic functions and biological structures such as cell membranes. Besides being structural components, glycolipids show surface activity in the interfaces and are mainly produced by microorganisms. Interest in biosurfactants has increased considerably in recent times due to their applications in the environmental, oil, food, and pharmaceutical industries, since they have unique properties such as low toxicity, high biodegradability, environmentally friendly, foaming capacity, high selectivity and specificity at extreme temperatures, pH and salinity, as well as biological activity. All of these properties are considered advantages over other chemical surfactants, and therefore glycolipids are considered a good alternative, given the current interest on sustainable development. The present work shows a general view of bio-surfactants of microbial origin, particularly of glycolipids, referring to several studies on their biological activity that have revealed their great potential in the medical–biological field, discovering interesting possibilities for their therapeutic application in the near future.

Langmuir monolayers of amphiphilic molecules at an air-water interface can be compressed laterally to achieve high surface density. However, compression beyond a certain threshold causes the monolayer to become unstable, which may lead to the formation of collapsed states with topographical differences that are associated with the structures and mechanical properties of the constituent molecules of the monolayer. The mechanisms and collapsed structures can differ owing to differences in experimental conditions, i.e., temperature, ion-content, the pH of subphase, or compression rate; in addition, the type of constituent molecules, i.e., biological lipids or chemical surfactants, has an effect. In this review, we compare studies concerning several aspects of collapse, from basic concepts and theoretical mechanisms to experimental visualization of the monolayer topography. In addition, techniques often employed to study this subject are discussed in this review.

Severe bronchopulmonary dysplasia (BPD) is common disease, especially for the tiniest infants with gestational age