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The increasing demand for corrosion prevention strategies that are both effective and sustainable is part of the research the background. Nonionic surfactants offer a potential replacement for traditional corrosion inhibitors. These surfactants are well-known for their low toxicity and biodegradability. The research involved conducting experimental tests (such as weight loss, polarization and impedance spectroscopy) and theoretical computations to investigate the role of nonionic surfactant (polyoxyethylene (7) tribenzyl phenyl ether) (PETPE) in controlling the corrosion of mild steel in hydrochloric acid (1.0 M HCl) environment. The results of the study demonstrated that PETPE exhibited significant corrosion inhibition properties for mild steel in HCl solution. The inhibition efficiency of PETPE was found to increase with increasing PETPE concentration. PETPE is an excellent corrosion inhibitor because it significantly reduces the rate of corrosion, as seen by the notable inhibition efficiency result (95.4%) at a relatively low dose of PETPE (100 ppm). Thermodynamic studies were used to discuss the fundamental mechanisms that control PETPE-acid interactions. The adsorption process followed Langmuir adsorption isotherm, indicating a monolayer adsorption of the PETPE on the mild surface. Theoretical computations confirm the strong inhibition behavior of PETPE. The innovative feature of this research is its comprehensive strategy, which integrates experimental studies and theoretical simulations to evaluate the impact of PETPE on the corrosion control of mild steel in hydrochloric acid. The combined effort has the ability to supply valuable knowledge into the mechanisms of corrosion that will lead to the establishment of powerful corrosion control strategies.

Water and several chemicals, including dyestuffs, surfactants, acids, and salts, are required during textile dyeing processes. Surfactants are harmful to the aquatic environment and induce several negative biological effects in exposed biota. In this context, the present study aimed to assess acute effects of five surfactants, comprising anionic and nonionic classes, and other auxiliary products used in fiber dyeing processes to aquatic organisms Vibrio fischeri (bacteria) and Daphnia similis (cladocerans). The toxicities of binary surfactant mixtures containing the anionic surfactant dodecylbenzene sulfonate + nonionic fatty alcohol ethoxylate and dodecylbenzene sulfonate + nonionic alkylene oxide were also evaluated. Nonionic surfactants were more toxic than anionic compounds for both organisms. Acute nonionic toxicity ranged from 1.3 mg/L (fatty alcohol ethoxylate surfactant) to 2.6 mg/L (ethoxylate surfactant) for V. fischeri and from 1.9 mg/L (alkylene oxide surfactant) to 12.5 mg/L (alkyl aryl ethoxylated and aromatic sulfonate surfactant) for D. similis , while the anionic dodecylbenzene sulfonate EC50s were determined as 66.2 mg/L and 19.7 mg/L, respectively. Both mixtures were very toxic for the exposed organisms: the EC50 average in the anionic + fatty alcohol ethoxylate mixture was of 1.0 mg/L ± 0.11 for V. fischeri and 4.09 mg/L ± 0.69 for D. similis . While the anionic + alkylene oxide mixture, EC50 of 3.34 mg/L for D. similis and 3.60 mg/L for V. fischeri . These toxicity data suggested that the concentration addition was the best model to explain the action that is more likely to occur for mixture for the dodecylbenzene sulfonate and alkylene oxide mixtures in both organisms. Our findings also suggest that textile wastewater surfactants may interact and produce different responses in aquatic organisms, such as synergism and antagonism. Ecotoxicological assays provide relevant information concerning hazardous pollutants, which may then be adequately treated and suitably managed to reduce toxic loads, associated to suitable management plans.

Lipid nanocarrier displays the advantages over conventional drug carriers as they are formulated with biodegradable and non-irritant lipids. However, the main drawbacks are the agglomeration of lipid particles, instability over storage, low drug loading, and the burst release of active ingredients. In this study, we investigated the effects of various polysorbate nonionic surfactants namely Tween 20, 40, 60, or 80 on the nanostructured lipid carrier (NLC). NLC incorporated with polysorbate nonionic surfactant was prepared by using high-pressure homogenization technique. The average size was reduced to 139.9 ± 15.8 nm in the presence of Tween 80 and remained stable in nano-size even incubated for 28 days. Encapsulation of l-ascorbic acid or Gold Tri.E 30 showed a high encapsulation efficiency of more than 75%, where the highest was Gold Tri.E in the presence of Tween 60 at 99.7%. In vitro release study showed that the release of both l-ascorbic acid and Gold Tri.E was significantly reduced in NLC with Tween as compared to bare active ingredients and NLC without Tween. In conclusion, the incorporation of Tween successfully produced a lipid nanocarrier that has the potential to be developed as a carrier of various active ingredients such as nutrients, extracts, and drugs.

Petroleum hydrocarbons are applied in various energy activities. If accidents happen, they may result in environmental contamination, especially in soil. Petroleum hydrocarbons have low evaporation rates and are adsorbed on the soil surface, making it necessary to treat contaminated soil before the pollutants spread to other areas. Soil washing with surfactant solution is a method used to treat petroleum hydrocarbon contamination. The process relies on surfactant properties which reduce surface tension and desorb diesel from soil particles prior to flushing out with water. The relationship between efficiency of diesel extraction from contaminated soil and factors of both single surfactants (Span20, Tween20, Tween80, Dehydol LS9) and mixed surfactants (Span20+Tween20, Span20+Tween80, Span20+Dehydol LS9) were investigated including hydrophile-lipophile balance (HLB) and interfacial tension (IFT) to select a suitable surfactant. Diesel was analyzed by GC-FID. Findings revealed that extraction efficiency significantly increased when the HLB of the surfactant increased in every solution pair (p = 0.05). Span20+Dehydol LS9 solution with HLB 12 showed the lowest IFT (17.767 ± 0.013 mN/m) and the highest diesel extraction efficiency (66.2%). The water washing process, repeated twice after washing with 1% (w/v) Span20+Dedydol LS9, resulted in less toxicity on germination and growth of tomato, rice, and green bean compared with diesel washing solution and fresh washing solution. Diesel-contaminated soil washing with mixed surfactant is an interesting alternative as an environmentally friendly soil treatment.

Nonionic surfactants have been utilized to improve the enzymatic hydrolysis of lignocellulosic materials. However, the role of surfactant adsorption affecting enzymatic hydrolysis has not been elaborated well. In this work, nonionic surfactants differing in their molecular structures, namely the polyoxyethylene sorbitan monooleate (Tween 80), the secondary alcohol ethoxylate (Tergitol 15-S-9), and the branched alcohol ethoxylate (Tergitol TMN-6), were studied for their effects on the enzymatic hydrolysis of palm fruit bunch (PFB). The PFB was pretreated with a 10% w / v sodium hydroxide solution and then hydrolyzed using the cellulase enzyme from Trichoderma reesei (ATCC 26921) at 50 °C and pH 5. The optimal conditions providing similar yields of reducing sugar required Tween 80 and Tergitol TMN-6 at 0.25% w / v , while Tergitol 15-S-9 was required at 0.1% w / v . All the surfactants improved the enzymatic conversion efficiency and reduced unproductive binding of the enzyme to lignin. In addition, the adsorption isotherm of cellulase was fit well by the Freundlich isotherm, while adsorption of the three nonionic surfactants agreed well with the Langmuir isotherm. Adsorption capacities of the three nonionic surfactants were consistent with their enhancement efficiencies in hydrolysis. The critical micelle concentration was observed as a key property of nonionic surfactant for adsorption capacity.

Background Low concentrations of nonionic surfactants can change the physical properties of cell membranes, and thus and in turn increase drug permeability. Porcine circovirus 2 (PCV2) is an extremely slow-growing virus, and PCV2 infection of PK-15 cells yields very low viral titers. The present study investigates the effect of various nonionic surfactants, namely, Tween-20, Tween-28, Tween-40, Tween-80, Brij-30, Brij-35, NP-40, and Triton X-100 on PCV2 infection and yield in PK-15 cells. Result Significantly increased PCV2 infection was observed in cells treated with Tween-20 compared to those treated with Tween-28, Tween-40, Brij-30, Brij-35, NP-40, and Triton X-100 (p  < 0.01). Furthermore, 24 h incubation with 0.03% Tween-20 has shown to induce significant cellular morphologic changes (cell membrane underwent slight intumescence and bulged into a balloon, and the number of microvilli decreased), as well as to increase caspase-3 activity and to decrease cell viability in PCV2-infected PK-15 cells cmpared to control group; all these changes were restored to normal after Tween-20 has been washed out from the plate. Conclusion Our data demonstrate that Tween-20 transiently changes the surface morphology of PK-15 cells and improves PCV2 infection. The findings of the present study may be utilized in the development of a PCV2 vaccine.

This work introduces a simplified methodology for measuring the characteristic curvature (Cc) of commercial alkyl ethoxylate nonionic surfactants using carefully selected reference surfactants and oils that produce rapid and well defined separations in salinity scans. The Cc of the commercial reference surfactants was calculated using optimal salinities ( S *) obtained from solubilization parameter curves, from interfacial tensions (for a selected system), and from emulsion stability tests. The latter provided a fast detection of S *, in a matter of minutes. The calibrated Cc of the reference surfactants was subsequently used to measure the Cc of various commercial alkyl ethoxylate surfactants. The combination of mixtures of test and reference surfactants and emulsion stability tests produced reproducible Cc values that could be obtained with simple bottle tests and in a timely manner. The values obtained using this methodology were cross-checked, and proved to be consistent, when using different combinations of reference surfactants and oils, and when conducted by different individuals. The standard deviation of Cc from these measurements was typically ±0.2 Cc units, but it could be as large as 25 % of the Cc value for highly hydrophilic surfactants. After comparing the values of Cc obtained experimentally with values calculated from nominal structures (via a group contribution model) it became clear that there are differences between these values, likely because of the polydispersity of alkyl ethoxylate surfactants.

Growing cell submerged culture is usually applied for fermentative production of intracellular orange Monascus pigments, in which accumulation of Monascus pigments is at least partially associated to cell growth. In the present work, extractive fermentation in a nonionic surfactant micelle aqueous solution was utilized as a strategy for releasing of intracellular Monascus pigments. Those mycelia with low content of intracellular Monascus pigments were utilized as biocatalyst in resting cell submerged culture. By this means, resting cell submerged culture for production of orange Monascus pigments was carried out successfully in the nonionic surfactant micelle aqueous solution, which exhibited some advantages comparing with the corresponding conventional growing cell submerged culture, such as non-sterilization operation, high cell density (24 g/l DCW) leading to high productivity (14 AU of orange Monascus pigments at 470 nm per day), and recycling of cells as biocatalyst leading to high product yield (approximately 1 AU of orange Monascus pigments at 470 nm per gram of glucose) based on energy metabolism.

Milking processing describes the cultivation of microalgae in a water-organic solvent two-phase system that consists of simultaneous fermentation and secretion of intracellular product. It is usually limited by the conflict between the biocompatibility of the organic solvent to the microorganisms and the ability of the organic solvent to secret intracellular product into its extracellular broth. In the present work, submerged cultivation of Monascus in the nonionic surfactant Triton X-100 micelle aqueous solution for pigment production is exploited, in which the fungus Monascus remains actively growing. Permeabilization of intracellular pigments across the cell membrane and extraction of the pigments to the nonionic surfactant micelles of its fermentation broth occur simultaneously. \"Milking\" the intracellular pigments in the submerged cultivation of Monascus is a perstraction process. The perstractive fermentation of intracellular pigments has the advantage of submerged cultivation by secretion of the intracellular pigments to its extracellular broth and the benefit of extractive microbial fermentation by solubilizing the pigments into nonionic surfactant micelles. It is shown as the marked increase of the extracellular pigment concentration by the submerged cultivation of Monascus in the nonionic surfactant Triton X-100 micelle solution. [PUBLICATION ABSTRACT]

Monascus species can produce various secondary metabolites of polyketide structure. In the current study, it is found that an interesting phenomenon, i.e., submerged culture of Monascus species in an aqueous solution majorly accumulated intracellular orange Monascus pigments exhibiting one peak at 470 nm with absorbance of 32 OD while extractive fermentation in a nonionic surfactant micelle aqueous solution produced extracellular and intracellular yellow Monascus pigments exhibiting one peak at 410 nm with absorbance 30 OD and 12 OD, respectively. The spectrum profiles of both intracellular and extracellular Monascus pigments were affected by surfactant loading, extractive fermentation time, and surfactant adding time. Meanwhile, the instability of orange Monascus pigments in the extracellular nonionic surfactant micelle aqueous solution was also confirmed experimentally. The mechanism behind this phenomenon is attributed to the export of intracellular yellow Monascus pigments into its broth by extractive fermentation. The transferring of intracellular yellow Monascus pigments into its broth blocks yellow Monascus pigments from further enzymatic conversion or eliminates the feedback inhibition of yellow Monascus pigments based on the biosynthetic pathway of Monascus pigments.