Hydrophilic-lipophilic Balance Values Research Articles

An approach to mass produce peppermint oil-sodium alginate composite microcapsules by drop-on-demand system loaded with stabilized nanoemulsion

ABSTRACT Microencapsulation technology has found widespread applications in current fields of food industries. In this study, by combining water-in-oil emulsion with drop-on-demand (DOD) technique, we successfully produced sodium alginate (SA) shell microcapsules containing peppermint oil (PO). Response surface methodology (RSM) was employed to optimize the surfactant used for nanoemulsification. A comprehensive investigation into the morphology, structure, and encapsulation efficiency of resulting microcapsules was conducted. The study revealed that various parameters, especially of Hydrophilic-Lipophilic Balance (HLB) values, can affect the physical properties of PO/SA nanoemulsion. The optimized formulation achieved emulsions with a mean droplet size of 46.60 nm. Microcapsules with different shell/core ratios (2, 1, and 0.5) were prepared by pulse duration of 20 ms, exhibiting varying antibacterial activities against Escherichia coli in subsequent tests. This work confirms the feasibility of nanoemulsion-DOD system, highlighting the potential of PO/SA microcapsules as a more environmentally friendly alternative to conventional antimicrobials.

Green Formulation of Spironolactone Loaded Chitosan-Coated Nano Lipid Carrier for Treatment of Acne Vulgaris: A Randomized Double-Blind Clinical Trial.

Spironolactone (SPN), which is classified as an anti-androgen, has demonstrated efficacy in treating acne. This study aimed to utilize ultrasonication to create a chitosan-coated nano lipid carrier (NLC) for enhancing the delivery of SPN to the skin and treating acne. Various hydrophilic-lipophilic balance (HLB) values were investigated to optimize the SPN-NLCs. Photon correlation spectroscopy, attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), transmission electron microscopy (TEM), and differential scanning calorimetry (DSC) were employed to characterize the solid state of SPN in nanoparticle form. Additionally, the optimized formulation was used in a double-blind, randomized clinical trial. Reducing the HLB of the surfactant mixtures resulted in a reduction in the size of SPNNLCs. The formula with the smallest particle diameter (238.4±0.74 nm) and the lowest HLB value (9.65) exhibited the highest encapsulation efficiency (EE) of 79.88±1.807%. Coating the optimized SPN-NLC with chitosan increased the diameter, polydispersity index (PDI), zeta potential (ZP), and EE. In vitro skin absorption studies demonstrated sustained release profiles for chitosan-coated SPN-NLC. In the double-blind trial, a gel containing chitosan-coated SPN-NLC effectively treated mild to moderate acne vulgaris, leading to improved healing and reduced lesion count after 8 weeks of therapy compared to the placebo. It successfully addressed both non-inflammatory and inflammatory lesions without adverse effects on the skin. The findings indicate that chitosan-coated SPN-NLCs have the potential as nanoparticles for targeted SPN delivery to the skin, offering novel options for the treatment of acne vulgaris.

Nanoemulsion of Zanthoxylum rhetsa (Roxb.) DC: Formulation, release characteristics and its potential use for anti-inflammation applications

Nanoemulsions of Zanthoxylum rhetsa (Roxb.) DC fruit extract combined with eucalyptus oil (ZRNEs) were formulated using mixed surfactants at various Tween 80/Span 80 mass ratios of 20/80 (ZRNE-6), 50/50 (ZRNE-10), and 80/20 (ZRNE-13). These formulations had corresponding hydrophilic-lipophilic balance (HLB) values of 6, 10, and 13, respectively. Effect of the HLB on properties of the nanoemulsions were evaluated. Among these formulations, ZRNE-10, was found to be optimal for loading ZR extract with eucalyptus. It exhibited the smallest particle size of 402 ± 12 nm with a PDI of 0.41 ± 0.01, as analyzed by dynamic light scattering technique. ZRNE-10 showed the highest encapsulation efficiency for terpinen-4-ol at 83.42 ± 0.51%. It demonstrated a gradual release profile, releasing 30% of terpinen-4-ol within 48 h in a pH 7.4 PBS buffer at 37 °C. Interestingly, higher HLB values accelerated the release rate of terpinen-4-ol. The release kinetics of ZRNE-10 were best described by the Higuchi model (R2 = 0.903). ZRNE-10 displayed robust antioxidant activity (59.5 ± 1.6%) and effective inhibition of nitric oxide (76.9 ± 0.8%). It also exhibited low cytotoxicity on normal human skin fibroblasts (IC50 ≈ 3 mg/mL). Stability assessments revealed that all ZRNE formulations maintained their physical attributes and bioactivities even after one month of storage at 25 °C, and even at an elevated temperature of 45 °C. Notably, the antioxidant activities of ZRNEs surpassed those of unencapsulated ZR extract. Given their favorable anti-inflammatory properties, low cytotoxicity, and maintained efficacy, ZRNEs hold promise as potential ingredients for topical use.

Effect of Multifactor on the Stability of Glucose Solution Emulsified Heavy Fuel Oil.

Water emulsified heavy fuel oil (HFO) has been a promising alternative fuel for reducing oil consumption and preventing environmental pollution. However, the intrinsic challenges such as fuel formula, emulsion stability, and preparation process normally limit its further applications in energy-saving and emission reduction applications. In this study, the glucose obtained from biomass was added to a dispersed-phase aqueous solution of water emulsified HFO to prepare a novel alternative emulsified fuel. First, based on the preliminary experimental design, the effects of glucose and surfactant on the stability of the HFO emulsion were systematically evaluated through the appearance of emulsion separation, droplet size distribution, and rheological characteristics. It indicated that the surfactant ratio, hydrophilic-lipophilic balance value, solution ratio, and glucose/water ratio had significant impacts on emulsion stability. Subsequently, the optimum range of influencing factors of emulsion stability was determined by a single factor experiment and determined by the response surface methodology based on the Box-Behnken design; the optimal values of the above factors were 2.439 v/v%, 5.807, 26.462 v/v%, and 35.729%, respectively. Under these conditions, an optimal glucose solution emulsified HFO with a uniform brown color and long-term stability was obtained, making the unseparated emulsion ratio reach 98% (lasting for 7 days at 85 °C). Meanwhile, it emerged that the influence of multifactor on emulsion stability was not a simple linear correlation, and there were significant interactions between the solution ratio and the surfactant ratio, as well as between the glucose/water ratio and the surfactant ratio.

Antifungal activity of essential oil and emulsifiable concentrates of citronella and lemon grass against Phomopsis vexans

The present study aims to develop eco-friendly Emulsifiable Concentrates (EC) using citronella and lemon grass essential oil (EO) and evaluate its antifungal activity against Phomopsis vexans in Solanum melongena. Among nine prepared formulations, F1 formulation with EO (40%) + vegetable oil (50%) and emulsifier blends (10%) with hydrophilic-lipophilic balance value (12.86) were found suitable for both EO formulations. These formulations (CF1 and LF1) performed well in terms of emulsion stability, cold test, accelerated storage and foam test indicating feasibility for their commercial production. In laboratory studies, at 0.1% concentration, citronella essential oil, lemon grass essential oil and their EC formulations CF1 and LF1 inhibited the growth of P. vexans with EC50 values 0.0087, 0.0098, 0.009 and 0.0126, respectively. Further, under field conditions, CF1 performed better than LF1 formulation in terms of minimum disease severity (32.22%). Hence, EC formulations can be used as natural and eco-friendly fungicide for P. vexans control.

Chemically vs Enzymatically Synthesized Polyglycerol-Based Esters: A Comparison between Their Surfactancy.

Polyglycerol fatty acid esters (PGFAEs) are gaining interest in several industrial sectors due to their excellent surfactant properties and their wide range of hydrophilic-lipophilic balance (HLB) values. Moreover, they can be prepared from renewable resources, i.e., fatty acids and glycerol. In this study, polyglycerol-2 stearic acid esters (PG2SAEs) were synthesized by the enzymatic esterification of polyglycerol-2 (PG2) and stearic acid (SA) using the immobilized lipase Novozym 435 as a biocatalyst in a solvent-free system. Reaction conditions, i.e., temperature (80 °C), reactant ratio (1:1.8), and enzyme loading (2.7% w/w), were finely optimized; furthermore, biocatalyst recycling was studied by assessing the residual activity of the lipase after each reaction cycle, up to 20 times. The composition of the enzymatically synthesized products (E) was roughly evaluated by chromatographic methods and mass spectrometry and compared with that of the esters obtained by acid-catalyzed esterification (C). Then, the surfactant properties of the prepared polyglycerol-based surfactants were investigated by interfacial tension studies. Specifically, the emulsifying capacity and stability and the rheological behavior of O/W emulsions prepared in the presence of E were deeply investigated in comparison with those of the chemically synthesized and commercially available product C.

Nano-emulsification method as a strategy for oil soluble corrosion inhibitor transform to water soluble

Corrosion inhibitor is one of the most economical and effective approaches to protecting metal pipes in the oil and gas industries. However, a great amount of corrosion inhibitors such as imidazoline, are difficult to distribute fast due to their poor solubility or dispersibility in water, which results in inhomogeneous concentration distribution and ineffectiveness. In this study, nano-emulsification technique was developed to improve the dispersity of mercaptoacetic acid-modified oleic imidazoline (MOI) in corrosive water. The formulation of nanoemulsion is optimized with the phase inversion temperature (PIT) and droplet diameter. The prepared nanoemulsion which the hydrophilic lipophilic balance value (HLB) was 11.5 and the loading of corrosion inhibitor was 20 wt% exhibited remarkable water dispersion performance and its mean particle size was less than 100 nm. Moreover, its dispersion performance in water was significantly better than that of the paraffin oil system, and was similar in the ethanol system. The inhibition performances and mechanisms of nanoemulsion for L245 carbon steel in the H2S/CO2 containing 5.0 wt% NaCl solution were investigated with weight loss measurements and electrochemical tests. In terms of inhibition efficiency, the corrosion inhibitor encapsulated in nanoemulsion was exceeding 90%, which was comparable to the system employing ethanol and liquid paraffin as solvents. Further experimental results indicated that the nanoemulsion system was more consistent with the Freundlich adsorption model, unlike the other two systems which followed the Langmuir adsorption model. The morphology and composition of corrosion products were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) methods. The SEM and XPS results demonstrated that the nanoemulsion system did not change the material type of corrosion products, but had a visible influence on their morphology. In addition, the inhibition mechanism was also revealed by theoretical calculations. These findings suggest that nano-emulsification technique has the potential to improve the solubility or dispersibility of oil soluble corrosion inhibitor, thereby expanding its application fields.

Application of Alkyletanolamide Surfactants Based on Nyamplung (Callophylum Inophylum L.) Seed Oil in Cream Base

Cream preparation is cosmetic preparation consisting of aqueous and oil phases that immiscible. Thus, a surfactant with hydrophilic and lipophilic groups is needed to reduce the interfacial tension between the two phases. Petroleum-based surfactants such as Triethanolamine (TEA) are often used in the cosmetic industry. In this study, however, alkyletanolamide surfactant synthesized from vegetable oil was used. Nyamplung, Callophylum inophylum L. (C. inophylum) oil is one of non-commercial vegetable oil that can be used as a substitute to produce surfactants. The aims of this study was to apply surfactant synthesized from C. inophylum oil on the cream preparation and to characterize the alkylethanolamide surfactant by determining the value of hydrophilic-lipophilic balance (HLB). Four different surfactant concentration, 1.5%, 2.0%, 2.5% and 0% were tested as base for the cream preparation. The best surfactant concentration for the cream-based formulation obtained in this study was 2.5% and the surfactant HLB value obtained was 14.40 indicating that alkyletanolamide surfactants can be applied to the oil-in-water (O/W) type of cream base formula.

Safer and effective alternatives to perfluoroalkyl-based surfactants in etching solutions for the semiconductor industry

Surfactants based on poly and perfluoroalkyl substances (PFAS) such as Fluoroalkyl sulfonamide, fluoroalkyl sulfonyl amino propane sulfonic acid, and potassium perfluorooctane sulfonate surfactants are widely used in etching solutions in the semiconductor industry to improve the wetting characteristics of the etchant and substrates.Their excellent stability in strongly acidic, alkaline, and oxidizing etching solutions such as Tetramethyl ammonium hydroxide (TMAH), perchloric acid/ceric ammonium nitrate aqueous solution (chrome), ammonium hydrogen fluoride solution, or buffered oxide etchant (BOE) and a mixture of phosphoric, acetic, and nitric acid etchant (PAN), has warranted their continuous use as a surfactant.The toxicity and extremely high persistence of PFAS necessitate their replacement with less toxic and effective alternative surfactants.A generic methodology is described for the identification of safer alternative surfactants and the experimental validation of properties to facilitate the drop-in replacement of these safer surfactants in etching solutions for the semiconductor industry. Hydrophilic-Lipophilic Balance (HLB) values, critical micelle concentration (CMC), compatibility, and wetting characteristics of etchants were analyzed on substrates relevant to the semiconductor industry.Biobased BG10 alternative surfactant outperformed PFAS surfactant in improving the wetting characteristics of the TMAH etchant on substrates of interest as evidenced by the significantly lower contact angle. The wetting characteristics of the PAN and BOE etchants containing BG10 and CG50 surfactants were comparable to PFAS surfactants.Toxicity comparisons indicated that these alternatives are far less hazardous to human health than PFAS. These safer alternatives have been tested successfully by over 100 semiconductor companies. These companies have provided positive feedback with no reported deleterious effects on the final products. This successful approach opens new possibilities for the replacement of PFAS in numerous other applications where PFAS is commonly used as a surfactant. Using this methodology, alkyl polyglucosides with trade names BG10 and CG50 and polyoxyethylene surfactants of Brij35 and BrijS100 were identified as alternatives to PFAS surfactants.

Surfactant pretreatment as a novel fouling mitigation strategy for membrane distillation

Membrane distillation (MD) has emerged as a promising thermal desalination technology for hypersaline wastewater reclamation. However, the practical implementations of MD face a critical challenge of membrane fouling. Conventional strategy to address membrane fouling is to emphasize the progress in developing composite MD membranes, but these membranes are commercially unavailable. In this study, we introduce a new operation strategy to mitigate fouling by using surfactant pretreatment. We demonstrate that after being pretreated by 0.05 mM Triton X-100 feed solution for 10 min, a commercial polyvinylidene fluoride (PVDF) membrane can exhibit outstanding fouling resistance in MD process. Further, we elucidate the underlying working mechanism using quartz crystal microbalance (QCM) experiments, oil contact angle measurements, and force spectroscopy determinations. Specifically, in the pretreatment process, the amphiphilic surfactant adsorbs onto the hydrophobic membrane, altering the membrane surface to be hydrophilic. During the MD operations, a hydration layer forms on the hydrophilic surface, eliminating the foulant-membrane interaction and thereby achieving fouling mitigation. For effective fouling mitigation, a surfactant exhibiting a moderate hydrophilic-lipophilic balance (HLB) value (e.g., Triton X-100 with an HLB of ∼14) is required. As an easy-to-implement but effective strategy to mitigate membrane fouling, surfactant pretreatment can substantially improve the fouling resistances of commercial hydrophobic membranes, greatly facilitating the practical applications of MD and membrane contactor technologies.

Synthesis of polyglycerol fatty acid esters catalyzed by lipase and evaluation of its emulsification properties

The present study investigated the physicochemical properties of the newly synthesized polyglycerol fatty acid esters (PGFEs) and their potential application as food emulsifiers. It turned out that the complete removal of glycerol from crude polyglycerol was achieved by optimizing the molecular distillation temperature (120 °C). Moreover, novozym 435 was used to catalyze the synthesis of PGFEs with different aliphatic chain lengths, and the esterification rate of the obtained products was 93%∼98%. The characteristic absorption peak of the ester carbonyl group was displayed at 1738 cm−1, and that of C–O–C on the ether bond was at 1100 cm−1 and 1048 cm−1. Therefore, the synthesis can be determined to be PGFEs. Their hydrophilic lipophilic balance (HLB) values are >7, which can be used as oil-in-water emulsifiers. When curcumin nanoemulsions were constructed by PGFEs with various aliphatic chains as emulsifiers, it was found that all PGFEs in C10∼C18 can form stable curcumin nanoemulsions (encapsulation rate was >95%). PGFEs with longer aliphatic chains can stabilize nanoemulsions more efficiently (larger droplet sizes and lower ζ-electric potential), and showed better storage and UV stability. Whereas, medium-chain PGFEs emulsions, especially PGC, showed the best curcumin release efficiency, which theoretically supported the application of PGFEs to functional emulsion products.

Development of an in situ emulsifying/ultra-low-interfacial-tension cyclic flooding system for medium- and low-permeability reservoirs

Medium- and low-permeability reservoirs are important in oilfield development. However, due to their characteristics of poor pore permeability and high heterogeneity, the development of suitable technologies has been very difficult. In this study, an in situ emulsifying/ultra-low-interfacial-tension cyclic flooding system has been developed for low- and medium-permeability reservoirs. Based on the hydrophilic-lipophilic balance (HLB) value method, an emulsifying surfactant ASD with Span 80 (sorbitan monooleate) as the main component has been identified as highly promising through screening. At mass fractions of surfactant ASD between 0.2% and 0.6%, the extent of water separation from the emulsion is greatly reduced, and the W/O emulsion can effectively improve the mobility ratio and increase the sweep volume. The surfactant SA synthesized in our laboratory reduces the interfacial tension of crude oil to 10−4 mN m−1. Laboratory core flooding experiments have shown that multiple rounds of alternating injection with aqueous solutions of surfactants ASD and SA can improve oil recovery by 22.25%. Upon injecting a low-viscosity aqueous solution of surfactant ASD, it emulsifies crude oil in situ under reservoir conditions, solving the problems of difficult polymer injection and insufficient spread. Our work provides useful insights for the development of low- and medium-permeability reservoirs.

Effect of hydrophilic/lipophilic balance on the porogenic properties of non-ionic surfactants for monolith preparation and chromatographic separation

The effect of hydrophilic/lipophilic balance (HLB) of polyoxyethylene ethers of different chain lengths on the microporogenic properties of the Brij surfactants has been studied. The objective of this work is to help better understand the role of each porogen and to set criteria for selecting the proper non-ionic surfactant, based on the HLB value. Seven recipes of different porogen compositions were first prepared and the highest efficiency was achieved using decane/decanol/dodecanol mixture with Brij® 30. Then, four other Brij surfactants covering the entire HLB scale were tested, and the prepared monoliths were characterized by SEM, BET, FT-IR and chromatography. The results showed that increasing the HLB from 9.72 to 18.84 was accompanied by an increase in monolith density and surface areas. The optimum HLB range was found to be 10 to 15. Surfactants of lower HLB formed either nonporous or less efficient columns, while those of higher HLB formed non-permeable columns. Adjusting the HLB was possible by mixing surfactants of different HLB. The prepared monoliths could be used in the isocratic mode with a mobile phase consisting of a mixture of ACN and water (20:80, v/v) at a flow rate of 1.5 μL min−1 to separate five sulfa drugs. The separation results showed that the elution order of the compounds correlated with their lipophilicity, with sulfamerazine (logp = 0.52) being the first to elute, and sulfaquinoxoline (logp=1.70) being the most retained. The asymmetry factors of the separated compounds ranged between 1.18 and 1.25, and the resolution was found to be in the range 2.92−7.80. The prepared monoliths could be also successfully separate a mixture of four different nonsteroidal anti-inflammatory drugs and a mixture of four benzoic acid derivatives. This work assists in optimizing the surfactant-based porogenic mixture to meet the desired porosity, surface area, morphology and chromatographic separation requirements.

The Effects of Surfactant and Metal Ions on the Stability and Rheological Properties of Nanoemulsions Loaded with Gardenia Yellow Pigment

The present work reports the preparation of gardenia yellow pigment containing paraffin oil nanoemulsions stabilized by Span80 and Tween80. The preparation of the required nanoemulsions was optimized by testing different conditions, such as varying the hydrophilic–lipophilic balance (HLB), the emulsifier concentration (EC), the oil–water ratio (OWR), and the temperature (T), as determined by the average droplet diameter (ADD) and polydispersity index (PDI). Our results indicated that a minimum ADD of 65.9 nm and PDI of 0.116 were obtained at an optimum HLB value of 6.0, EC of 10% (w/w), OWR of 2:1, and T of 40 °C. Both the steady-state and dynamic rheological parameters were further investigated, revealing that the emulsions exhibited pseudoplastic behaviors. The long-term stabilities of the nanoemulsions after the addition of inorganic salts were monitored by observing their visual appearances. It was found that the emulsions containing pure water or 0.1 M CaCl2 and AlCl3 became slightly separated, while the emulsions containing 0.1 M KCl and NaCl showed no separation after 30 days of storage at room T. This difference among different salts could be related to the number of valence electrons of their cations. The spatial electrostatic effects of the monovalent cationic (KCl and NaCl) and the nonionic surfactants were greater than the delamination/sedimentation forces of the system, which was better than the salt based on the cations with valences greater than one (CaCl2 and AlCl3). In conclusion, the present work illustrated the formation, rheological properties, and stability of water containing gardenia yellow pigment in paraffin oil nanoemulsions, which can be of great significance for the application of gardenia-yellow-pigment-based formulations.

Nanoemulsions of terpene by-products from cannabidiol production have promising insecticidal effect on Callosobruchusmaculatus

Nanoemulsions of a terpene-rich by-product (TP) from commercial cannabidiol (CBD) production were successfully formulated and characterized. An enriched terpene distillate (DTP) was also obtained from steam distillation of TP and used for making nanoemulsions. The effects of formulation conditions including the hydrophilic lipophilic balance (HLB) value of the surfactant, TP and surfactant content, and sonication time on the properties of the emulsions were analyzed. The optimal formulation conditions were determined as surfactant HLB value of 13, TP content of 5 wt% in water, surfactant content of 2 times of TP, and sonication time of 1.5 min. A scaled-up production of the optimal nanoemulsion was also achieved using a microfluidizer and the effect of pressure and number of passes on emulsion properties was determined. The stability of the nanoemulsions was evaluated and the DTP nanoemulsion was determined to be the most stable. The nanoemulsions with desirable properties were then selected and evaluated for their insecticidal activity against the legume pest, Callosobruchus maculatus, with nanoemulsion of neem oil made under the same conditions as a control. Both TP and DTP nanoemulsions were found to exhibit excellent insecticidal activity, and the latter had the highest efficacy against the Callosobruchus maculatus.

Preparation of Antibacterial Nanosilver Solution Microcapsules and Their Impact on the Performance of Andoung Wood Surface Coating.

In this paper, nanosilver solution was used as an antibacterial agent to prepare antibacterial microcapsules. The mass ratio of the core material to the wall material (Wcore: Wwall), the emulsifier's hydrophilic-lipophilic balance (HLB) value, the mass ratio of ethanol to the emulsifier in solvent (Wcore: Wemulsion), and the rotational speed (r/min) were used to develop the four-factor, three-level orthogonal experiment, which was meant to investigate the most significant factors and the optimum process preparation parameters impacting the coating rate and yield of microcapsules. It was used to make an antibacterial coating that was applied to the surface paint film of a glass substrate and andoung wood, and it was mixed to the water-based primer with a content of 4%. Analyses of the mechanical, optical, and bactericidal characteristics were conducted. The micromorphology of the nanosilver solution microcapsules is influenced by the emulsifier's HLB value. The color difference of the antibacterial coating film decreased with increasing emulsifier HLB value; however, the coating film's gloss remained largely suitable. Additionally, the coating film's transparency and tensile strength both decreased. It had minimal impact on the paint film's surface hardness, but the adhesion and tensile strength showed a noticeable downward trend. The surface of the paint film was rough. Escherichia coli and Staphylococcus aureus were resistant to the antibacterial characteristics of the water-based primer film when it was combined with antibacterial nanosilver solution microcapsules by 80.7% and 74.55%, respectively. The coating film's antibacterial properties were applied to the surface of the andoung wood, which were 75.7% and 71.0%, respectively, and somewhat decreased. In order to successfully inhibit bacteria, the nanosilver solution microcapsules were added to waterborne coatings. This ensures both the outstanding performance of the coating film and the effectiveness of the antibacterial effect. It expands the application prospects of antibacterial microcapsules in coatings.

Recent Trends in Improving the Oxidative Stability of Oil-Based Food Products by Inhibiting Oxidation at the Interfacial Region

In recent years, new approaches have been developed to limit the oxidation of oil-based food products by inhibiting peroxidation at the interfacial region. This review article describes and discusses these particular approaches. In bulk oils, modifying the polarity of antioxidants by chemical methods (e.g., esterifying antioxidants with fatty alcohol or fatty acids) and combining antioxidants with surfactants with low hydrophilic-lipophilic balance value (e.g., lecithin and polyglycerol polyricinoleate) can be effective strategies for inhibiting peroxidation. Compared to monolayer emulsions, a thick interfacial layer in multilayer emulsions and Pickering emulsions can act as a physical barrier. Meanwhile, high viscosity of the water phase in emulsion gels tends to hinder the diffusion of pro-oxidants into the interfacial region. Furthermore, applying surface-active substances with antioxidant properties (such as proteins, peptides, polysaccharides, and complexes of protein-polysaccharide, protein-polyphenol, protein-saponin, and protein-polysaccharide-polyphenol) that adsorb at the interfacial area is another novel method for enhancing oil-in-water emulsion oxidative stability. Furthermore, localizing antioxidants at the interfacial region through lipophilization of hydrophilic antioxidants, conjugating antioxidants with surfactants, or entrapping antioxidants into Pickering particles can be considered new strategies for reducing the emulsion peroxidation.

Effect of dispersant on catalyst ink properties and catalyst layer structure for high performance polymer electrolyte membrane fuel cells

Here, catalyst ink is prepared using a dispersant with the hydrophile-lipophile balance (HLB) value of 17. The effects of the ionomer-catalyst agglomerate size on the ink rheological properties, and subsequent catalyst layer (CL) microstructure and electrochemical performance are investigated to elucidate the relationship between ink properties and cell performance. Results shows that the smallest agglomerate size (2.7 μm) and polydispersity index (PDI, 0.068) are obtained with 1 wt% dispersant content; the low PDI indicate that the ink is well dispersed. Steady-state and thixotropy tests also show that the ink has shear-thinning and gel-like behavior (Recovery ratio: 30.4%). It is proposed that this occurs because the agglomerates are smaller and the interaction forces between them increase. Thus, the ink structure is maintained until the dried CL is formed, and as a result, the pore volume of CL with 1 wt% dispersant is increased compared to those with 0 and 9 wt%. In addition, the 1 wt% CL-based MEA shows the highest performance (1224.4 mA cm−2 at 100% RH) owing the increase in the number of channels (1190 mA cm−2 in four-channel) and back pressure (1240 mA cm−2 at 1.5 barca).

Comprehensive application possibility: Construction hydrophilic, amphiphilic and hydrophobic system of modified zein by enzymatic or cysteine modification

Zein, a hydrophobic protein due to high percentage of apolar amino acids, which limits its modification and wide application in the food industry. The interaction between the molecule and water will be changed by introducing different hydrophilic groups into zein, which is the basis aimed at food application. Therefore, zein was modified based on construction of zein-potassium oleate system to obtain hydrophilic, amphiphilic and hydrophobic systems, thus the structure and properties of modified zein were explored in the present study. The results of the three-phase contact angle showed that the constructed zein-potassium oleate system is a hydrophobic system. After enzymatic modification, a hydrophilic system can be obtained. Amphiphilic system can be obtained by cysteine modification. Sodium dodecyl sulfate polyacrylamide gel electrophoresis, gel size exclusion chromatography, hydrophilic-lipophilic balance value, free amino group and sulfhydryl group results can also prove the hydrophilic and hydrophobic system obtained by different modification methods. Ultraviolet, Infrared and fluorescence spectra of zein after enzymatic hydrolysis and cysteine modification indicated that the hydrophilicity and hydrophobicity of the zein microenvironment also changed. This study may provide a feasible approach to broaden the application of zein in food industry. • Two modification methods were used to realize the construction of different systems of zein. • The formation of different systems is directly or indirectly demonstrated in a number of ways. • This paper provides a feasible approach to broaden the application of zein in food industry.

The antiaging cream characteristics from extract of turmeric (Curcuma domestica Val.) rhizome and tamarind (Tamarindus indica L.) leaves

Chemical-based cosmetics tend to have adverse side effects on human skin so that public awareness arises to use cosmetics made from natural ingredients that do not have side effects. Extract cream of turmeric and tamarind leaf is one of the cosmetics made from natural ingredients that has the potential to replace chemical-based cosmetics. This study aims to determine the hydrophilic lipophilic balance (HLB) value and perfume type to get the cream with the best characteristics, an extract mixture concentration of turmeric rhizome and tamarind leaves used in the manufacture of anti-aging cream, and its application. The experiment used randomized block design with HLB treatment: 9,10,11 and the perfume type : 1,5% jasmine, 2% champagne, 2% rose, while the mixed treatment of turmeric extracts and tamarind leaves extracts were used with the concentration of 0, 1, 2, 3, 4, 5%. The application of the cream to experimental animals, using 36 wistar rats (Rattus norvegicus), treated without cream, smeared with placebo cream, smeared with cream of a mixture of tamarind leaves and turmeric extracts, for 4 weeks all groups of rats received exposure chronic UV-B rays 840 mJ/cm. The results showed that the type of perfume had a significant effect on the dispersion, but HLB and the type of perfume had a significant effect on overall acceptance. HLB 10 cream in all types of perfumes showed the best cream characteristics. The lowest anti-collagenase IC50 value was obtained in the cream with a 5% concentration of turmeric extract and tamarind leaves, IC50 value: 0.36 g/ml. Application of cream mixture of turmeric rhizome extract and tamarind leaves with a concentration of 5% gave a significant effect on the decrease in MMP-1 expression up to 12.147+2.380 μg/ml and increase the amount of collagen by 23. 67% in the skin of wistar rats.