Search Results (1,763)

Biosurfactants, amphiphilic metabolites produced by bacteria and yeasts, fulfill a variety of functions in microbial life. They exhibit a well-recognized multifunctionality, spanning from the reduction in surface tension to specific biological activities, including antimicrobial, antiviral, anti-inflammatory, and anticancer effects. These compounds have the potential to serve as environmentally friendly alternatives to synthetic surfactants in industrial formulations, where they could act as emulsifiers and wetting agents. The exploitation of their full potentiality could be a significant added value. Biosurfactants are often cited as effective antioxidants. However, experimental evidence for their antioxidant activity/capacity is sparse. To shed light on the subject, in this review we collect and critically examine all the available literature data for each of the major classes of microbial biosurfactants: rhamnolipids, mannosylerythritol lipids, sophorolipids, and lipopeptides. Despite the variability arising from the diverse composition and polydispersity of the samples analyzed, along with the variety of testing methodologies, the findings consistently indicate a moderate-to-strong antioxidant capacity. Several hypotheses are advanced about the molecular mechanisms behind this action; however, further studies are needed to gain a molecular understanding. This knowledge would fully define the biological roles of biosurfactants and is a prerequisite for the development of innovative formulations based on the valorization of their antioxidant properties. Full article

This study aims to optimize the demulsification performance of a carbon quantum dot (CQD)-enhanced chemical demulsifier in industrial emulsions under thermal, mechanical, and thermomechanical effects. Experiments were conducted to assess treatments like organic treatment (OT), zeta potential modifier aqueous solution (ZPMAS), and acid treatment (9.25 wt.% HCl) at varying dosages, along with CQD–chemical mixtures optimized through a simplex-centroid mixture design (SCMD) to minimize basic sediment and water (BSW). Under the thermomechanical scenario, a system with 500 mg∙L⁻¹ CQDs and OT achieves 0.5% BSW and a droplet size of 63 nm, while an SCMD-optimized system (500 mg∙L⁻¹ CQDs + 380 mg∙L⁻¹ OT + 120 mg∙L⁻¹ ZPMAS) achieves 0% BSW and larger droplets (>70 nm). CQDs enhance demulsifiers by destabilizing water-in-oil (W/O) Pickering emulsions, leveraging their nanometric size, high surface area, thermal conductivity, and amphiphilicity, thanks to their hydrophobic core and surface hydrophilic groups (-OH, NH₂, -COOH). This research enhances the understanding of demulsification by employing green demulsifiers based on CQDs and provides a promising cost-efficient solution for breaking stable emulsions in the petroleum industry. It minimizes the use of complex and expensive active ingredients, achieving BSW values below 0.5%, the standard required for crude oil transport and sale, while also reducing separation equipment operation times, and improving overall process efficiency. Full article

Cassava peels are rich in polysaccharides but highly unexplored and underutilized, as they could be used to meet the increasing demand for clean-label foods. This study investigated the effect of temperature on the solubilization of cassava peel during hydrothermal treatment to determine the emulsifying ability of solubilized cassava peel (SCP). Subcritical water conditions were employed via hydrothermal (120–200 °C; 2 MPa) or autoclave (127 °C; 0.2 MPa) treatments to solubilize cassava peels. The composition of the SCPs was determined, and their emulsifying ability was assessed using interfacial tension and zeta potential measurements. Under the best treatment conditions (140 °C at 2 MPa [hydrothermal]; 127 °C at 0.2 MPa [autoclave]), SCPs reduced interfacial tension against soybean oil to 12.9 mN/m and 13.4 mN/m, respectively. A strengthened co-emulsifier system was developed by incorporating SCPs with Quillaja saponins (QS) or Tween 20 to enhance the performance. Dynamic interfacial tension and zeta potential measurements revealed synergistic interactions, showing a remarkable reduction in interfacial tension from 12.94 to 5.33 mN/m. This suggests that the SCP has a surfactant-like structure owing to its amphiphilic structure and hydrophobic chains (nonpolar region) attached to the -OH functional group (polar region). Combining a second surface-active compound or co-emulsifier results in an additive effect, reducing the interfacial tension. These findings provide novel insights into carbohydrate-saponin binding and elucidate the impact of peel composition, concentration, and hydrothermal treatment conditions on co-emulsifier system performance, which will assist in the development of emulsifiers, contributing to the advancement of clean-label food technologies, effectively replacing synthetic emulsifiers in food formulations, and offering both sustainability and functionality. A systematic investigation of processing conditions and co-emulsifier interactions provides a practical framework for developing high-performance natural emulsifiers from agricultural waste. Full article

Significant progress has been achieved in the development of superabsorbent polymers (SAPs), focusing on enhancing their performance and expanding their applications. Efforts are particularly directed at increasing water absorbency while promoting environmental sustainability. Biodegradable materials such as starch and potassium humate have been successfully integrated with SAPs for desert greening, improving water retention, salt resistance, and seedling survival. The inclusion of nutrient-rich organic-inorganic composites further enhances the durability, efficiency, and recyclability of SAPs. In drought mitigation, polymeric absorbent resins such as polyacrylamide and starch-grafted acrylates have shown efficacy in ameliorating soil conditions and fostering plant growth. In arid environments, agents enriched with humic acid and bentonite contribute to improved soil aeration and water retention, creating optimal conditions for plant establishment. Additionally, the adoption of innovative waste management solutions has led to the production of amphiphilic SAPs from residual sludge, effectively addressing soil nutrient deficiencies and environmental pollution. In the food industry, SAPs containing protease, tea polyphenols, and chitosan exhibit potential for enhancing the stability and quality of seafood products. These advancements highlight the growing relevance of structural optimization approaches in SAP development across diverse applications and underline the importance of continued innovation in these fields. As novel materials emerge and environmental challenges intensify, the potential applications of SAPs are anticipated to expand significantly. Full article

Self-assembly of amphiphilic molecules is an important phenomenon attracting a broad range of research. In this work, we study the self-assembly of KTOF₄ sphere–rod amphiphilic molecules in mixed water–dioxane solvents. The molecules are of a T-shaped geometry, comprised of a hydrophilic spherical Keggin-type cluster attached by a flexible bridge to the center of a hydrophobic rod-like oligodialkylfluorene (OF), which consists of four OF units. Transmission electron microscopy (TEM) uncovers self-assembled spherical structures of KTOF₄ in dilute solutions. These spheres are filled with smectic-like layers of KTOF₄ separated by layers of the solution. There are two types of layer packings: (i) concentric spheres and (ii) flat layers. The concentric spheres form when the dioxane volume fraction in the solution is 35–50 vol%. The flat layers are formed when the dioxane volume fraction is either below (20 and 30 vol%.) or above (55 and 60 vol%.) the indicated range. The layered structures show no in-plane orientational order and thus resemble thermotropic smectic A liquid crystals and their lyotropic analogs. The layered packings reveal edge and screw dislocations. Evaporation of the solvent produces a bulk birefringent liquid crystal phase with textures resembling the ones of uniaxial nematic liquid crystals. These findings demonstrate that sphere–rod molecules produce a variety of self-assembled structures that are controlled by the solvent properties. Full article

Poor water solubility remains a significant challenge in the pharmaceutical industry that limits the therapeutic efficacy and bioavailability of many active pharmaceuticals. Soluplus^® (SLP), an amphiphilic graft copolymer made of polyethylene glycol, polyvinyl caprolactam, and polyvinyl acetate, has been gaining interest in recent years as it addresses these limitations by acting as a versatile carrier. Its ability to form stable amorphous dispersions and enhance drug solubility, as well as its physicochemical properties, support its role as a key excipient in advanced drug delivery systems. Recent investigations have demonstrated the adaptability of SLP in addressing drug delivery requirements, offering controlled release, improved targeting, and superior therapeutic outcomes. This review examines some key formulation methods that make use of SLP, including hot-melt extrusion, spray drying, electrospinning, drug–polymer layering, and capsule and tablet formulations, highlighting the capacity of SLP to overcome formulation challenges. Biomedical applications of SLP have also been explored, with a focus on its role in improving the delivery of antitumoral, anti-inflammatory, antimicrobial, and antiparasitic drugs. Full article

Low-molecular-mass gelators (LMMGs) as stabilizers for gel emulsions offer numerous advantages, such as low usage, functionalizability, and insensitivity to phase ratio. Using LMMGs as stabilizers is one of the effective strategies for preparing gel emulsions. Currently, developing LMMGs and stable gel emulsion systems in a rapid and convenient manner remains a challenge. To cope with the challenge, this study aims to develop a simple and efficient gel emulsion preparation method based on LMMGs. In this study, a cholesterol-based star-shaped derivative (CSD) was designed and synthesized as an LMMG. Based on gelation experiments, a high internal phase W/O gel emulsion system (H₂O/CSD-poly(oligo)-dimethylsiloxane/dichloromethane) was successfully developed and stabilized synergistically by the stabilizer (CSD) and the crosslinker (poly(oligo)-dimethylsiloxane with two olefinic bonds at its ends, D-PDMS). The results demonstrate that the synergistic interaction between CSD and D-PDMS is critical for the formation of the gel emulsion. Building on the original gel emulsion system, two novel in situ polymerizable gel emulsion systems (H₂O/CSD-D-PDMS/dichloromethane-tert-butyl methacrylate and H₂O/CSD-D-PDMS/dichloromethane-N-tert-butyl methacrylamide) were successfully developed by introducing suitable amphiphilic (hydrophilic/lipophilic) polymerizable monomers. This study found that changes in the amphiphilicity of the introduced monomers significantly affected the stability and microscopic morphology of the gel emulsion system. The findings indicate that constructing a hydrophilic/lipophilic balanced system via the synergistic action of stabilizers and crosslinkers in a solvent system, followed by the introduction of polymerizable monomers, is a simple and efficient method for rapidly developing novel polymerizable gel emulsions. These new polymerizable gel emulsions lay the foundation for the subsequent preparation of porous organic polymers (POPs). Full article

Highly symmetric protein cages represent one of the most artistic architectures formed by biomolecules. However, the underlying reasons for the formation of some of these architectures remain unknown. The present study aims to investigate the significance behind their morphological formation by fabricating protein cage-like vesicles using a synthetic polymer. The vesicles were synthesized by combining polymerization-induced self-assembly (PISA) with polymerization-induced microphase separation (PIMS), employing an amphiphilic poly(methacrylic acid)-block-poly(n-butyl methacrylate-random-cyclohexyl methacrylate-random-methacrylic acid) diblock copolymer, PMAA-b-P(BMA-r-CMA-r-MAA). The copolymer, with a 60 mol% molar ratio of CMA to the BMA units, produced clathrin-like vesicles with angular windows in their shell, resulting from the segregation of the hard CMA units from the soft BMA matrix in the hydrophobic phase of the vesicle. These vesicles were highly stable against rising temperatures. In contrast, the vesicles with a 30 mol% CMA ratio dissociated upon heating to 50 °C into triskelion-like segments due to intramolecular microphase separation. These findings indicate that designing synthetic polymers can mimic living organ morphologies, aiding in elucidating their morphological significance and inspiring the development of new materials utilizing these morphologies. Full article

Microfluidic devices are greatly affected by the materials used. The materials used in previous studies had problems in various aspects, such as processing, adsorption, and price. This study will investigate the materials needed to overcome such problems. Various microfluidic devices based on the perfluorinated compound perfluoropolyether (PFPE) were fabricated and mixed with hydrophilic and amphiphilic monomers, including poly(ethylene glycol) diacrylate, polyethylene glycol monomethacrylate, poly(ethylene glycol) methyl ether methacrylate, acrylic acid, and 2-hydroxyethyl methacrylate. A PFPE-based sheet with a repeating structure of hydrophobic and hydrophilic groups was fabricated. Thus, the hydrophilicity of highly hydrophobic PFPE was enhanced. The fluidic channel was engraved on a PFPE-based sheet using laser cutting and a fabricated microfluidic device. The channels of microfluidic devices are micro-scale (100 µm~300 µm). The lipid nanoparticles and droplets generated through the microfluidic device demonstrated uniform particles continuously. Full article

Royal jelly and medical grade honey are traditionally used in treating wounds and infections, although their effectiveness is often variable and insufficient. To overcome their limitations, we created novel amphiphiles by modifying the main reparative and antimicrobial components, queen bee acid (hda) and 10-hydroxyl-decanoic acid (hdaa), through peptide bonding with specific tripeptides. Our molecular design incorporated amphiphile targets as being biocompatible in wound healing, biodegradable, non-toxic, hydrogelable, prohealing, and antimicrobial. The amphiphilic molecules were designed in a hda(hdaa)-aa1-aa2-aa3 structural model with rational selection criteria for each moiety, prepared via Rink/Fmoc-tBu-based solid-phase peptide synthesis, and structurally verified by NMR and LC–MS/MS. We tested several amphiphiles among those containing moieties of hda or hdaa and isoleucine–leucine–aspartate (ILD-amidated) or IL-lysine (ILK-NH₂). These tests were conducted to evaluate their prohealing and antimicrobial hydrogel properties. Our observation of their hydrogelation and hydrogel-rheology showed that they can form hydrogels with stable elastic moduli and injectable shear-thinning properties, which are suitable for cell and tissue repair and regeneration. Our disc-diffusion assay demonstrated that hdaa-ILK-NH₂ markedly inhibited Staphylococcus aureus. Future research is needed to comprehensively evaluate the prohealing and antimicrobial properties of these novel molecules modified from hda and hdaa with tripeptides. Full article

Kefir-based fermentation products exhibit antioxidant and anti-inflammatory effects against oxidative stress, inflammation, platelet activation and aggregation, and other related manifestations, thereby preventing the onset and development of several chronic diseases. Specifically, water kefir, a symbiotic culture of various microorganisms used for the production of several bio-functional fermented products, has been proposed for its health-promoting properties. Thus, water kefir grains and its apple pomace-based fermentation beverage were studied for bioactive amphiphilic and lipophilic lipid compounds with antioxidant, antithrombotic, and anti-inflammatory properties. Total lipids (TL) were extracted and further separated into their total amphiphilic (TAC) and total lipophilic content (TLC), in which the total phenolic and carotenoid contents (TPC and TCC, respectively) and the fatty acid content of the polar lipids (PL) were quantified, while the antioxidant activity of both TAC and TLC were assessed in vitro, by the ABTS, DPPH, and FRAP bioassays, along with the anti-inflammatory and antithrombotic activity of TAC against human platelet aggregation induced by the thrombo-inflammatory mediator, platelet-activating factor (PAF) or standard platelet agonists like ADP.ATR-FTIR spectra facilitated the detection of specific structural, functional groups of phenolic, flavonoid, and carotenoid antioxidants, while LC−MS analysis revealed the presence of specific anti-inflammatory and antithrombotic PL bioactives bearing unsaturated fatty acids in their structures, with favorable omega-6 (n-6)/omega-3 (n-3)polyunsaturated fatty acids (PUFA), which further support the findings that the most potent antioxidant, anti-inflammatory and antithrombotic bioactivities were observed in the TAC extracts, in both water kefir grains and beverage cases. The detection of such bioactive components in both the uncultured water kefir grains and in the cultured beverage further supports the contribution of water kefir microorganisms to the bioactivity and the bio-functionality of the final fermented product. Nevertheless, the extracts of the beverage showed much stronger antioxidant, anti-inflammatory, and antithrombotic activities, which further suggests that during the culture process for producing this beverage, not only was the presence of bioactive compounds produced by kefir microflora present, but biochemical alterations during fermentation of bioactive components derived from apple pomace also seemed to have taken place, contributing to the higher bio-functionality observed in the apple pomace—water kefir-based beverage, even when compared to the unfermented apple pomace. The overall findings support further studies on the use of water kefir and/or apple pomace as viable sources of antioxidant, anti-inflammatory, and antithrombotic amphiphilic bioactive compounds for the production of novel health-promoting bio-functional fermented products. Full article

There is relatively little research on cyclic amphiphilic block polymers, having both hydrophilic and hydrophobic segments placed in the ring and thus resulting in a higher degree of topological restriction, as drug vehicles. Cyclic amphiphilic binary block polymer is synthesized by the click coupling reaction of bimolecular homodifunctional precursors. The results indicate that cyclization between linear polymer precursors is successful if the trace linear by-products generated are ignored, which also suggests that the small molecule bifunctional terminating agent applied in traditional bimolecular homodifunctional ring-closure process can be extended to large molecule. Moreover, the study on the self-assembly behavior of polymers shows that, compared with linear counterparts, the stability and drug loading capacity of micelles based on the resultant cyclic polymer are not significantly improved due to the influence of topological structure and linear impurities. Nevertheless, drug loaded micelles formed by the obtained cyclic polymers still exhibit superior cellular uptake ability. It can be seen that topological effects do play an irreplaceable role in the application performance of polymers. Therefore, the construction and synthesis of cyclic and its derivative polymers with moderate topological confinement and high purity may be a key direction for future exploration of polymer drug delivery carriers. Full article

Biomimetic nanoassemblies derived from natural products are considered promising nanomaterials due to their self-assembling ability and their favorable interactions with biological molecules leading to their numerous applications as therapeutic agents or as molecular probes. In this work, we have created peptide nanoconjugates of two natural products, β-Boswellic acid (BA) and β-glycyrrhetinic acid (GH). Both BA and GH are known for their medicinal value, including their role as strong antioxidants, anti-inflammatory, neuroprotective and as anti-tumor agents. To enhance the bioavailability of these molecules, they were functionalized with three short peptides (YYIVS, MPDAHL and GSGGL) to create six conjugates with amphiphilic structures capable of facile self-assembly. The peptides were also derived from natural sources and have been known to display antioxidant activity. Depending upon the conjugate, nanofibers, nanovesicles or a mixture of both were formed upon self-assembly. The binding interactions of the nanoconjugates with α-Synuclein, a protein implicated in Parkinson’s disease (PD) was examined through in silico studies and FTIR, circular dichroism and imaging studies. Our results indicated that the nanoassemblies interacted with alpha-synuclein fibrils efficaciously. Furthermore, the nanoassemblies were found to demonstrate high viability in the presence of microglial cells, and were found to enhance the uptake and interactions of α-Synuclein with microglial cells. The nanoconjugates designed in this work may be potentially utilized as vectors for peptide-based drug delivery or for other therapeutic applications. Full article

The antioxidant, antithrombotic and anti-inflammatory effects of the amphiphilic compounds extracted from both avocado juice and by-products, were evaluated. All extracts were assessed for their total phenolic content (TPC) and total carotenoid content (TCC), and for their antioxidant activities by DPPH, ABTS and FRAP assays as well as for their anti-inflammatory and antithrombotic potency in human platelets. The extracts rich in TAC (Total Amphiphilic Content) showed much higher content in phenolics and carotenoids from the extracts of total lipophilic content (TLC), which was reflected by the much stronger antioxidant capacities of TAC extracts. ATR-FTIR spectroscopy revealed the presence of not only phenolics and carotenoids, but also of bioactive polar lipids (PLs) in avocado TAC extracts, the LC-MS based structural analysis of which further revealed a fatty acid composition favourable for unsaturated fatty acids (UFAs) versus saturated ones (SFAs), including monounsaturated fatty acids (MUFAs) like the oleic acid (C18:1n9) and omega-3 (n3) polyunsaturated fatty acids (PUFAs) like the alpha linolenic acid (C18:3n3), with the subsequent anti-inflammatory low values of the n6/n3 PUFA ratio. The presence of such bioactive PLs that are rich in UFA within the TAC extracts of avocado juice and its by-products provide an explanation for the observed potent anti-inflammatory and antithrombotic activities of avocado TAC against thrombo-inflammatory mediators like platelet activating factor (PAF) and against standard platelet agonists like ADP, offering promise for such avocado TAC extracts, as ingredients in functional products for health/promoting applications either in cosmetics or in functional foods and nutraceuticals, or even drugs. Full article

The development of Pickering interfacial catalysts for organic reactions in water is of great importance to the development of green chemistry. In this study, amphiphilic hydrochar was prepared by a simple urea-modified hydrothermal carbonization with cellulose as an environmentally benign carbon source. It was found that the addition of urea could not only promote the carbonization of cellulose but also introduce N atoms to the final hydrochar material and tune the amphiphilicity of the hydrochar. Palladium nanoparticles supported on the amphiphilic N-doped hydrochar exhibited high activity in the Suzuki reaction in aqueous media. It can be seen that amphiphilic hydrochar can effectively stabilize Pickering emulsion, increase interface surface area, and further accelerate the Suzuki reaction. Full article