Search Results (47)

Selective insertion of lipid probes from the external milieu into raft regions of the cell membrane would enable targeted studies of raft molecular organization and of raft-associated peptide and glycan components. In this work, we compared the insertion of several synthetic glycolipids into raft and non-raft membrane areas of Raji and EA.hy 926 endothelial cells. A glyco-cholesterol derivative in which the 3β oxygen atom is replaced by NH was selected as a candidate raft-selective probe. Although this glycolipid also inserted into other membrane areas, its raft-to-non-raft distribution ratio was higher than that of its O-analog (natural 3β-O-cholesterol). Full article

Rhamnolipids are a class of glycolipids known for their surface and emulsifying activity. These molecules, produced by a few Gram-negative genera, mostly Pseudomonas, offer natural alternatives to synthetic surfactants in different industrial fields. This study examines the emulsifying and encapsulation performance of Rhamnolipids derived from the marine Antarctic bacterium Pseudomonas gessardii M15, comparing its emulsification ability and stability with those of commercial surfactants, Sodium dodecyl sulfate (SDS) and sucrose esters (SE), under extreme conditions of temperature and pH. The Rhamolipids were used to encapsulate Coenzyme Q10 with Arabic gum as the carrier matrix. Rhamnolipids exhibited surface and emulsifying activity comparable to that of SDS and superior to SE at neutral and basic pH levels. Their performance declined under acidic conditions, whereas exposure to 90 °C had no significant effects. The encapsulation efficiency of Coenzyme Q10 was significantly higher in the case of Rhamnolipids, with a percentage of encapsulated compound of 99.6 ± 0.2%, compared to the 38.2 ± 7.1% found when SDS was used. Rhamnolipids extracted from Pseudomonas gessardii M15 exhibit strong potential as a natural surfactant, particularly in formulations that require thermal stability and effective encapsulation. These findings support its use as a sustainable alternative to synthetic agents in diverse industrial settings. Full article

Bio-based surfactants have demonstrated significant potential as economically viable and environmentally sustainable alternatives to petroleum-derived surfactants, with the global biosurfactant market expanding from USD 4.41 billion in 2023 to a projected USD 6.71 billion by 2032, representing a compound annual growth rate of 5.4%. While conventional surfactants such as alkyl aryl sulfates and alkyl benzene sulfonates exhibit extremely high aquatic toxicity and impose substantial ecological costs, biosurfactants including lipopeptides (surfactin, iturin, fengycin, lichenysin) produced by Bacillus species and glycolipids (rhamnolipids, sophorolipids, trehalose lipids, mannosylerythritol lipids) from Pseudomonas demonstrate superior biodegradability. However, current biosurfactant production costs, ranging from 5 to20 USD/kg, cannot compete effectively with synthetic surfactants, averaging approximately 2 USD/kg, necessitating comprehensive process improvements to achieve commercial viability. The utilization of renewable agricultural feedstocks containing 65–70% carbohydrates, including corn stover, sugarcane bagasse, rice bran, and palm oil mill effluent, has achieved production costs as low as 3.8 USD/kg through advanced optimized pretreatment technologies, enzyme catalysis, simultaneous saccharification and fermentation (SSF), and downstream processes, resulting in cost reductions compared to conventional methods. The implementation of artificial intelligence and machine learning algorithms for bioprocess optimization enables simultaneous optimization of genetic engineering, metabolic pathways, and fermentation parameters, achieving yield improvements and cost reductions, with projections indicating production costs below 2.50 USD/kg being needed in the next decade to achieve cost parity with synthetic surfactants, maintaining economic viability. Full article

The cosmetics industry has been seeking to develop products with renewable natural ingredients to reduce the use of or even replace synthetic substances. Biosurfactants can help meet this demand. These natural compounds are renewable, biodegradable, and non-toxic or have low toxicity, offering minimal risk to humans and the environment, which has attracted the interest of an emerging consumer market and, consequently, the cosmetics industry. The aim of the present study was to produce a biosurfactant from the yeast Starmerella bombicola ATCC 22214 cultivated in a mineral medium containing 10% soybean oil and 5% glucose. The biosurfactant reduced the surface tension of water from 72.0 ± 0.1 mN/m to 33.0 ± 0.3 mN/m after eight days of fermentation. The yield was 53.35 ± 0.39 g/L and the critical micelle concentration was 1000 mg/L. The biosurfactant proved to be a good emulsifier of oils used in cosmetic formulations, with emulsification indices ranging from 45.90 ± 1.69% to 68.50 ± 1.10%. The hydrophilic–lipophilic balance index demonstrated the wetting capacity of the biosurfactant and its tendency to form oil-in-water (O/W) emulsions, with 50.0 ± 0.20% foaming capacity. The biosurfactant did not exhibit cytotoxicity in the MTT assay or irritant potential. Additionally, an antioxidant activity of 58.25 ± 0.32% was observed at a concentration of 40 mg/mL. The compound also exhibited antimicrobial activity against various pathogenic microorganisms. The characterisation of the biosurfactant using magnetic nuclear resonance and Fourier transform infrared spectroscopy revealed that the biomolecule is a glycolipid with an anionic nature. The results demonstrate that biosurfactant produced in this work has potential as an active biotechnological ingredient for innovative, eco-friendly cosmetic formulations. Full article

A major reason for the failure of the immune system to detect tumor antigens (TAs) is the insufficient uptake, processing, and presentation of TAs by antigen-presenting cells (APCs). The immunogenicity of TAs in the individual patient can be markedly increased by the in situ targeting of tumor cells for robust uptake by APCs, without the need to identify and characterize the TAs. This is feasible by the intra-tumoral injection of α-gal micelles comprised of glycolipids presenting the carbohydrate-antigen “α-gal epitope” (Galα1-3Galβ1-4GlcNAc-R). Humans produce a natural antibody called “anti-Gal” (constituting ~1% of immunoglobulins), which binds to α-gal epitopes. Tumor-injected α-gal micelles spontaneously insert into tumor cell membranes, so that multiple α-gal epitopes are presented on tumor cells. Anti-Gal binding to these epitopes activates the complement system, resulting in the killing of tumor cells, and the recruitment of multiple APCs (dendritic cells and macrophages) into treated tumors by the chemotactic complement cleavage peptides C5a and C3a. In this process of converting the treated tumor into a personalized TA vaccine, the recruited APC phagocytose anti-Gal opsonized tumor cells and cell membranes, process the internalized TAs and transport them to regional lymph-nodes. TA peptides presented on APCs activate TA-specific T cells to proliferate and destroy the metastatic tumor cells presenting the TAs. Studies in anti-Gal-producing mice demonstrated the induction of effective protection against distant metastases of the highly tumorigenic B16 melanoma following injection of natural and synthetic α-gal micelles into primary tumors. This treatment was further found to synergize with checkpoint inhibitor therapy by the anti-PD1 antibody. Phase-1 clinical trials indicated that α-gal micelle immunotherapy is safe and can induce the infiltration of CD4+ and CD8+ T cells into untreated distant metastases. It is suggested that, in addition to converting treated metastases into an autologous TA vaccine, this treatment should be considered as a neoadjuvant therapy, administering α-gal micelles into primary tumors immediately following their detection. Such an immunotherapy will convert tumors into a personalized anti-TA vaccine for the period prior to their resection. Full article

Biosurfactants are amphipathic molecules with considerable potential for application in different industries due to their biochemical characteristics, low toxicity as well as greater biodegradability and stability compared to chemical surfactants when submitted to adverse environmental conditions. The aim of the present study was to investigate the production of a biosurfactant by Candida lipolytica UCP 0988 grown in a medium containing 4.0% molasses, 2.5% used soybean frying oil, and 2.5% corn steep liquor for 144 h at 200 rpm. The biosurfactant was characterized; its stability and toxicity were investigated, and the compound was applied in oil removal tests. In the C. lipolytica growth and biosurfactant production studies, the surface tension of the medium was reduced from 72 mN/m to 25 mN/m, the critical micellar concentration (CMC) was 0.5 g/L (w/v), and the yield was 12 g/L. Tests under extreme conditions of temperature, pH, and NaCl indicated the stability of the biosurfactant. Fourier-transform infrared and nuclear magnetic resonance spectroscopy of the chemical structure of the purified biosurfactant suggested that the biosurfactant is a glycolipid. The anionic biosurfactant exhibited no toxicity to the microcrustacean Artemia salina or vegetable seeds (Brassica oleracea). Dispersion tests in seawater demonstrated 100% efficiency of the biomolecule against motor oil. The biosurfactant was efficient at removing oil from sand in static and kinetic tests at concentrations of ½ CMC (0.25 g/L), CMC (0.5 g/L), and 2 × CMC (1.0 g/L), with removal rates of 70 to 96%, whereas the synthetic surfactants tested removed only 10 to 18% of the oil. Based on the findings, the biosurfactant analyzed has considerable potential for the remediation of contaminated coastal and marine environments due to oil spills. Full article

During the last few decades, water pollution has become a growing concern at international level. To date, only a few Candida parapsilosis strains were successfully used in environmental remediation. In the present article, the strain C. parapsilosis CMGB-YT was studied for its ability to assimilate hydrophobic substrates and to produce biosurfactants with antimicrobial activity and positive effects on heavy metal removal from contaminated wastewaters. The strain C. parapsilosis CMGB-YT was grown on yeast peptone (YP) media with 1% n-decane, n-dodecane, n-tetradecane, n-hexadecane, as well as commercial sunflower and olive oils. The production of the biosurfactant was evaluated using the emulsification index (E_24%). The surface properties and emulsifying stability of the biosurfactant were determined. The effect of the biosurfactant on the cell growth of two strains of Rhodotorula mucilaginosa and on their removal capacity of lead (0.032 g/L) and cadmium (0.030 g/L) ions from synthetic wastewater were also studied. The antimicrobial potential of 20 mg/mL and 40 mg/mL biosurfactant was established in the presence of pathogenic Candida krusei strains. C. parapsilosis CMGB-YT assimilated n-hexadecane with good rates over 216 h and produced an anionic glycolipidic biosurfactant with stable E_24% towards long-chain carbon compounds at different temperatures, with an alkaline pH and high salinity (10% NaCl). The biosurfactant reduced the surface tension to 53.58 ± 0.42 mN/m, while the critical micellar concentration (CMC) was reached at 4.2% biosurfactant. The crude biosurfactant (5%) enhanced R. mucilaginosa growth in heavy metal-contaminated wastewater, increased chemical oxygen demand (COD) removal of up to 80%, and improved Cd²⁺ removal by 10%. Additionally, the concentrated biosurfactant effectively prevented Candida krusei biofilm formation. In conclusion, the biosurfactant produced by C. parapsilosis CMGB-YT demonstrates promising potential for the efficient treatment of wastewater contaminated with heavy metals and microbial pathogens. Full article

Surfactants, also known as surface-active agents, have emerged as an important class of compounds with a wide range of applications. However, the use of chemical-derived surfactants must be restricted due to their potential adverse impact on the ecosystem and the health of human and other living organisms. In the past few years, there has been a growing inclination towards natural-derived alternatives, particularly microbial surfactants, as substitutes for synthetic or chemical-based counterparts. Microbial biosurfactants are abundantly found in bacterial species, predominantly Bacillus spp. and Pseudomonas spp. The chemical structures of biosurfactants involve the complexation of lipids with carbohydrates (glycolipoproteins and glycolipids), peptides (lipopeptides), and phosphates (phospholipids). Lipopeptides, in particular, have been the subject of extensive research due to their versatile properties, including emulsifying, antimicrobial, anticancer, and anti-inflammatory properties. This review provides an update on research progress in the classification of surfactants. Furthermore, it explores various bacterial biosurfactants and their functionalities, along with their advantages over synthetic surfactants. Finally, the potential applications of these biosurfactants in many industries and insights into future research directions are discussed. Full article

An incomplete Freund’s adjuvant elicited an overt pathogenesis in vaccinated mice following the intranasal challenge of A/California/07/2009 (H1N1) virus despite the induction of a higher specific antibody titer than other adjuvanted formulations. Aluminum hydroxide adjuvants have not induced any pathogenic signs in a variety of formulations with glycolipids. A glycolipid, α-galactosyl ceramide, improved a stimulatory effect of distinct adjuvanted formulations on an anti-influenza A antibody response. In contrast to α-galactosyl ceramide, its synthetic analogue C34 was antagonistic toward a stimulatory effect of an aluminum hydroxide adjuvant on a specific antibody response. The aluminum hydroxide adjuvant alone could confer complete vaccine-induced protection against mortality as well as morbidity caused by a lethal challenge of the same strain of an influenza A virus. The research results indicated that adjuvants could reshape immune responses either to improve vaccine-induced immunity or to provoke an unexpected pathogenic consequence. On the basis of these observations, this research connotes the prominence to develop a precision adjuvant for innocuous vaccination aimed at generating a protective immunity without aberrant responses. Full article

Acidic sophorolipids (Acidic SL), congeners of sophorolipid biosurfactants, offer a potential alternative to synthetic sodium lauryl ether sulphate (SLES) in skincare applications. However, major challenges associated with the laboratory-based investigations of the cytotoxic effects of Acidic SL have been the utilisation of impure and/or poorly characterised congeners as well as the use of monolayers of skin cells in in vitro assays. While the former limitation makes glycolipids less attractive for use in academic research and skincare applications, the latter does not provide an accurate representation of the in vivo human skin. The present study, therefore, for the first time, assessed the cytotoxic effects of 96% pure Acidic SL on a 3D in vitro skin model in comparison with SLES, with the aim of investigating a natural alternative to synthetic surfactants for potential use in skincare applications. The 3D in vitro skin model was colonised with Staphylococcus epidermidis for 12 h, and afterwards treated with either Acidic SL or SLES at 100 μg mL⁻¹ for a further 12 h. Subsequently, the cytotoxic effects of Acidic SL in comparison with SLES were assessed using a combination of microbiology, molecular biology techniques, immunoassays, and histological analyses. It was demonstrated that Acidic SL had no deleterious effects on the viability of S. epidermidis, tissue morphology, filaggrin expression, and the production of inflammatory cytokines in comparison to SLES. These findings, in conjunction with the possibility to produce Acidic SL from cheaper renewable natural resources, demonstrate that Acidic SL could offer a potential sustainable alternative to synthetic surfactants. Full article

Glycolipids are biocompatible and biodegradable amphiphilic compounds characterized by a great scientific interest for their potential applications in various technological areas, including pharmaceuticals, cosmetics, agriculture, and food production. This report summarizes the available synthetic methodologies, physicochemical properties, and biological activity of sugar fatty acid ester surfactants, with a particular focus on 6-O-glucose, 6-O-mannose, 6-O-sucrose, and 6′-O-lactose ones. In detail, the synthetic approaches to this class of compounds, such as enzymatic lipase-catalyzed and traditional chemical (e.g., acyl chloride, Steglich, Mitsunobu) esterifications, are reported. Moreover, aspects related to the surface activity of these amphiphiles, such as their ability to decrease surface tension, critical micelle concentration, and emulsifying and foaming ability, are described. Biological applications with a focus on the permeability-enhancing effect across the skin or mucosa, antimicrobial and antifungal activities, as well as antibiofilm properties, are also presented. The information reported here on sugar-based ester surfactants is helpful to broaden the interest and the possible innovative applications of this class of amphiphiles in different technological fields in the future. Full article

The recruitment of leukocytes from blood is one of the most important cellular processes in response to tissue damage and inflammation. This multi-step process includes rolling leukocytes and their adhesion to endothelial cells (EC), culminating in crossing the EC barrier to reach the inflamed tissue. Galectin-8 and galectin-9 expressed on the immune system cells are part of this process and can induce cell adhesion via binding to oligolactosamine glycans. Similarly, these galectins have an order of magnitude higher affinity towards glycans of the ABH blood group system, widely represented on ECs. However, the roles of gal-8 and gal-9 as mediators of adhesion to endothelial ABH antigens are practically unknown. In this work, we investigated whether H antigen–gal-9-mediated adhesion occurred between Jurkat cells (of lymphocytic origin and known to have gal-9) and EA.hy 926 cells (immortalized endothelial cells and known to have blood group H antigen). Baseline experiments showed that Jurkat cells adhered to EA.hy 926 cells; however when these EA.hy 926 cells were defucosylated (despite the unmasking of lactosamine chains), adherence was abolished. Restoration of fucosylation by insertion of synthetic glycolipids in the form of H (type 2) trisaccharide Fucα1-2Galβ1-4GlcNAc restored adhesion. The degree of lymphocyte adhesion to native and the “H-restored” (glycolipid-loaded) EA.hy 926 cells was comparable. If this gal-9/H (type 2) interaction is similar to processes that occur in vivo, this suggests that only the short (trisaccharide) H glycan on ECs is required. Full article

The 21st century has seen a substantial increase in the industrial applications of glycolipid biosurfactant technology. The market value of the glycolipid class of molecules, sophorolipids, was estimated to be USD 409.84 million in 2021, with that of rhamnolipid molecules projected to reach USD 2.7 billion by 2026. In the skincare industry, sophorolipid and rhamnolipid biosurfactants have demonstrated the potential to offer a natural, sustainable, and skin-compatible alternative to synthetically derived surfactant compounds. However, there are still many barriers to the wide-scale market adoption of glycolipid technology. These barriers include low product yield (particularly for rhamnolipids) and potential pathogenicity of some native glycolipid-producing microorganisms. Additionally, the use of impure preparations and/or poorly characterised congeners as well as low-throughput methodologies in the safety and bioactivity assessment of sophorolipids and rhamnolipids challenges their increased utilisation in both academic research and skincare applications. This review considers the current trend towards the utilisation of sophorolipid and rhamnolipid biosurfactants as substitutes to synthetically derived surfactant molecules in skincare applications, the challenges associated with their application, and relevant solutions proposed by the biotechnology industry. In addition, we recommend experimental techniques/methodologies, which, if employed, could contribute significantly to increasing the acceptance of glycolipid biosurfactants for use in skincare applications while maintaining consistency in biosurfactant research outputs. Full article

The need to protect human and environmental health and avoid the widespread use of substances obtained from nonrenewable sources is steering research toward the discovery and development of new molecules characterized by high biocompatibility and biodegradability. Due to their very widespread use, a class of substances for which this need is particularly urgent is that of surfactants. In this respect, an attractive and promising alternative to commonly used synthetic surfactants is represented by so-called biosurfactants, amphiphiles naturally derived from microorganisms. One of the best-known families of biosurfactants is that of rhamnolipids, which are glycolipids with a headgroup formed by one or two rhamnose units. Great scientific and technological effort has been devoted to optimization of their production processes, as well as their physicochemical characterization. However, a conclusive structure–function relationship is far from being defined. In this review, we aim to move a step forward in this direction, by presenting a comprehensive and unified discussion of physicochemical properties of rhamnolipids as a function of solution conditions and rhamnolipid structure. We also discuss still unresolved issues that deserve further investigation in the future, to allow the replacement of conventional surfactants with rhamnolipids. Full article

Larix olgensis is an economically important tree species native to northeastern China. The use of somatic embryogenesis (SE) is efficient and enables the rapid production of varieties with desirable qualities. Here, isobaric labeling via tandem mass tags was used to conduct a large-scale quantitative proteomic analysis of proteins in three critically important stages of SE in L. olgensis: the primary embryogenic callus, the single embryo, and the cotyledon embryo. We identified 6269 proteins, including 176 shared differentially expressed proteins across the three groups. Many of these proteins are involved in glycolipid metabolism, hormone response/signal transduction, cell synthesis and differentiation, and water transport; proteins involved in stress resistance and secondary metabolism, as well as transcription factors, play key regulatory roles in SE. The results of this study provide new insights into the key pathways and proteins involved in SE in Larix. Our findings have implications for the expression of totipotency, the preparation of synthetic seeds, and genetic transformation. Full article