Keratin Microspheres as Promising Tool for Targeting Follicular Growth.

Skin is the body barrier that constrains the infiltration of particles and exogenous aggression, in which the hair follicle plays an important role. Recent studies have shown that small particles can penetrate the skin barrier and reach the hair follicle, making them a potential avenue for delivering hair growth-related substances. Interestingly, keratin-based microspheres are widely used as drug delivery carriers in various fields. In this current study, we pursue the effect of newly synthesized 3D spherical keratin particles on inducing hair growth in C57BL/6 male mice and in human hair follicle dermal papilla cells. The microspheres were created from partially sulfonated, water-soluble keratin. The keratin microspheres swelled in water to form spherical gels, which were used for further experiments. Following topical application for a period of 20 days, we observed a regrowth of hair in the previously depleted area on the dorsal part of the mice in the keratin microsphere group. This observation was accompanied by the regulation of hair-growth-related pathways as well as changes in markers associated with epidermal cells, keratin, and collagen. Interestingly, microsphere keratin treatment enhanced the cell proliferation and the expression of hair growth markers in dermal papilla cells. Based on our data, we propose that 3D spherical keratin has the potential to specifically target hair follicle growth and can be employed as a carrier for promoting hair growth-related agents.

Self-stabilizing performance of γ-oryzanol in oil-in-water emulsions and solid dispersions.

The surface activity of γ-oryzanol was evaluated by the pendant drop method (PDM), and its self-stabilizing properties were investigated by high-pressure homogenization (HPH) and solvent displacement method (SDM). Emulsions prepared by HPH were highly unstable due to the poor surface-active character of γ-oryzanol as identified by the PDM. In contrast, solid dispersions fabricated by SDM had comparable particle size to those prepared using Tween 80 (T80) as surfactant, and were stable up to 30 days of storage at 4 °C. The self-stabilizing properties of γ-oryzanol were attributed to the mechanism of spontaneous particle formation in SDM and to the ability of γ-oryzanol molecules to prevent particles aggregation by electrostatic repulsion. The outcome of this study indicates the potential of encapsulating selected bioactive compounds, such as γ-oryzanol, in stable colloidal systems by SDM without adding emulsifier(s), regardless of their surface-active character.

A Descriptive Whole-Genome Transcriptomics Study in a Stem Cell-Based Tool Predicts Multiple Tissue-Specific Beneficial Potential and Molecular Targets of Carnosic Acid.

Carnosic acid (CA) is a phenolic diterpene widely distributed in herbal plants, rosemary and sage. Although its medicinal properties, such as antioxidant, antimicrobial, and neuroprotective effects, have been well-documented, its relevant biochemical processes and molecular targets have not been fully explored yet. In the present study, we conducted an untargeted whole-genome transcriptomics analysis to investigate CA-induced early biological and molecular events in human amniotic epithelial stem cells (hAESCs) with the aim of exploring its multiple tissue-specific functionalities and potential molecular targets. We found that seven days of CA treatment in hAESCs could induce mesoderm-lineage-specific differentiation. Tissue enrichment analysis revealed that CA significantly enriched lateral plate mesoderm-originated cardiovascular and adipose tissues. Further tissue-specific PPI analysis and kinase and transcription factor enrichment analyses identified potential upstream regulators and molecular targets of CA in a tissue-specific manner. Gene ontology enrichment analyses revealed the metabolic, antioxidant, and antifibrotic activities of CA. Altogether, our comprehensive whole-genome transcriptomics analyses offer a thorough understanding of the possible underlying molecular mechanism of CA.

Improvements in Visual Aspects and Chemical, Techno-Functional and Rheological Characteristics of Cricket Powder (Gryllus bimaculatus) by Solvent Treatment for Food Utilization.

This study aimed to improve the visual aspects and chemical, techno-functional and rheological characteristics of Gryllus bimaculatus cricket powder through the use of different solvents, with the objective of using it as a protein source in food production. Four treatments (pH 5 aqueous solution, ethanol 20%, ethanol 99.5%, and hexane) were applied to the powder, and analyses were conducted to assess changes in the previously mentioned parameters. The results showed that the treatments led to an increase in protein concentration (from 55.4 to 72.5%) and a decrease in fat concentration (from 33.0 to 6.8%) in ethanol 99.5% treated powder, as well as a reduction in anti-nutritional compounds concentration, such as tannins (from 13.3 to 5.9 g/kg), in pH 5 treated powder, which is important for the nutritional value of the final product. The color of the powders was improved, being lighter after hexane and ethanol 99.5% treatments due to the removal of melanin with the defatting process. Flowability, water, and oil holding capacity were also improved in the defatted powders. All the results suggest that the main composition of the powder directly influences the analyzed parameters. These findings suggest that cricket powder treated with solvents can be used as a protein source in different food applications.

Monodisperse CaCO3-loaded gelatin microspheres for reversing lactic acid-induced chemotherapy resistance during TACE treatment.

Transarterial chemoembolization (TACE) is an important approach for the treatment of unresectable hepatocellular carcinoma (HCC). However, the lactic acid-induced acidic tumor microenvironment (TME) may reduce the therapeutic outcome of TACE. Herein, monodispersed gelatin microspheres loaded with calcium carbonate nanoparticles (CaNPs@Gel-MS) as novel embolic agents were prepared by a simplified microfluidic device. It was found that the particle size and homogeneity of as-prepared CaNPs@Gel-MS were strongly dependent on the flow rates of continuous and dispersed phases, and the inner diameter of syringe needle. The introduction of CaNPs provided the gelatin microspheres with an enhanced ability to encapsulate the chemotherapeutic drug of DOX, as well as a pH-responsive sustained drug release behavior. In vitro results revealed that CaNPs@Gel-MS could largely increase the cellular uptake and chemotoxicity of DOX by neutralizing the lactic acid in the culture medium. In addition, CaNPs@Gel-MS exhibited an excellent and persistent embolic efficiency in a rabbit renal model. Finally, we found that TACE treatment with DOX-loaded CaNPs@Gel-MS (DOX/CaNPs@Gel-MS) had a much stronger ability to inhibit tumor growth than the DOX-loaded gelatin microspheres without CaNPs (DOX@Gel-MS). Overall, CaNPs@Gel-MS could be a promising embolic microsphere that can significantly improve anti-HCC ability by reversing lactic acid-induced chemotherapy resistance during TACE treatment.

Encapsulation of D-Limonene into O/W Nanoemulsions for Enhanced Stability.

The present study aimed to investigate the physical stability in terms of (droplet size, pH, and ionic strength) and chemical stability in terms of (retention) of D-limonene (LM) in the nanoemulsions after emulsification as well as after storing them for 30 days under different temperatures (5 °C, 25 °C, and 50 °C). LM is a cyclic monoterpene and a major component extracted from citrus fruits. The modification of disperse phase with soybean oil (SB) and a nonionic emulsifier (Tween 80) was adequate to prepare stable LM-loaded nanoemulsions. LM blended with SB-loaded nanoemulsions were stable against droplet growth over pH (3-9) and ionic strength (0-500 mM NaCl). Regarding long-term storage, the prepared nanoemulsions demonstrated excellent physical stability with droplet size ranging from 120-130 nm during 30 days of storage at both 5 °C and 25 °C; however, oiling off started in the emulsions, which were stored at 50 °C from day 10. On the other hand, the retention of LM in the emulsions was significantly impacted by storage temperature. Nanoemulsions stored at 5 °C had the highest retention of 91%, while nanoemulsions stored at 25 °C had the lowest retention of 82%.

Revisiting lycopene extraction: Caprylic acid-based emulsion for the highest recovery.

In this study, we evaluated the caprylic acid-based oil-in-water (O/W) emulsion-assisted extraction of lycopene from tomatoes. Emulsion-assisted extraction was performed using two types of micron-sized O/W emulsions: (a) O/W emulsion with absence or (b) presence of 0.1% (w/w) of Tween 20 emulsifier. This green extraction technique was compared with the conventional method using soybean oil, tributyrin, and caprylic acid. The results show that caprylic acid, a green solvent, is significantly more effective for lycopene recovery than soybean oil and tributyrin. In the absence of an emulsifier, caprylic acid-based O/W emulsion significantly improved the lycopene content by 14.69 mg/g, corresponding to a 98.59% extraction efficiency at 50 ˚C. The capability of the proposed approach to lycopene recovery was explained in terms of lycopene affinity, the ability to swell the tomato cell, and some other standard parameters. In addition, caprylic acid has the significant advantage that once developed with the extracted lycopene can be used directly as a food additive.

Analysis of Calcium Sulfate Scaling Phenomena on Reverse Osmosis Membranes by Scaling-Based Flux Model.

In this study, the behavior of permeate flux decline due to scale precipitation of calcium sulfate on reverse osmosis membranes was investigated. The proposed scaling-based flux model is able to explain that permeate fluxes attributed to three mechanisms of scale precipitation-cake formation, surface blockage, and mixed crystallization-converge to the same newly defined scaling-based critical flux. In addition, a scaling index is defined, which determines whether scale precipitates on the membrane. The experimental results were analyzed based on this index. The mass-transfer coefficients of flat membrane cells used in the experiments were measured and, although the coefficients differed, they could be summarized in the same form as the Leveque equation. Considering the results of the scale precipitation experiments, where the operating conditions of pressure, solute concentration, temperature, and Reynolds number were varied, the convergent values of the permeate fluxes are explained by the scaling-based critical fluxes and the scale precipitation zones by the scaling indexes.

Monodispersed Sirolimus-Loaded PLGA Microspheres with a Controlled Degree of Drug-Polymer Phase Separation for Drug-Coated Implantable Medical Devices and Subcutaneous Injection.

Monodispersed sirolimus (SRL)-loaded poly(lactic-co-glycolic acid) microspheres with a diameter of 1.8, 3.8, and 8.5 µm were produced by high-throughput microfluidic step emulsification─solvent evaporation using single crystal silicon chips consisted of 540-1710 terraced microchannels with a depth of 2, 4, or 5 µm arranged in 10 parallel arrays. Uniform sized droplets were generated over 25 h across all channels. Nearly 15% of the total drug was released by the initial burst release during an accelerated drug release testing performed at 37 °C using a hydrotropic solution containing 5.8 M N,N-diethylnicotinamide. After 24 h, 71% of the drug was still entrapped in the particles. The internal morphology of microspheres was investigated by fluorescence microscopy using Nile red as a selective fluorescent stain with higher binding affinity toward SRL. By increasing the drug loading from 33 to 50 wt %, the particle morphology evolved from homogeneous microspheres, in which the drug and polymer were perfectly mixed, to patchy particles, with amorphous drug patches embedded within a polymer matrix to anisotropic patchy Janus particles. Janus particles with fully segregated drug and polymer regions were achieved by pre-saturating the aqueous phase with the organic solvent, which decreased the rate of solvent evaporation and allowed enough time for complete phase separation. This approach to manufacturing drug-loaded monodisperse microparticles can enable the development of more effective implantable drug-delivery devices and improved methods for subcutaneous drug administration, which can lead to better therapeutic treatments.

Enhancing the Formation and Stability of Oil-In-Water Emulsions Prepared by Microchannels Using Mixed Protein Emulsifiers.

Although natural emulsifiers often have many drawbacks when used alone, their emulsifying ability and stability can usually be improved unexpectedly when used in combination. In this study, monodisperse emulsions stabilized by combining two natural protein emulsifiers, i.e., whey protein isolate (WPI) and sodium caseinate (SC), in different proportions were prepared using microchannel (MC) emulsification. The influences of temperature, pH, ionic strength, and storage time on the microstructure and stability of the emulsions were examined. Analysis of the microstructure and droplet size distribution revealed that the WPI-, SC-, and mixed protein-stabilized emulsions exhibited uniform droplet distribution. The droplet size and ξ-potential of the MC emulsions stabilized by mixed protein emulsifiers were higher than those of the emulsions stabilized by WPI or SC separately. The emulsions stabilized by the two types of proteins and mixed emulsifiers had better stability under high salt concentrations than the synthetic emulsifier Tween 20. WPI-SC-stabilized emulsions were more resistant to high temperatures (70-90°C) and exhibited excellent stabilization than those stabilized by WPI and SC, which was attributed to the more sufficient coverage provided by the two types of protein emulsifier layers and better protein adsorption at the oil-water interface. These results indicate that WPI-SC is a potential stabilizer for MC emulsion requirements. This study provides a basis for the formulation of monodisperse and stable natural emulsion systems.

Formulation and physicochemical stability of oil-in-water nanoemulsion loaded with α-terpineol as flavor oil using Quillaja saponins as natural emulsifier.

Alpha-terpineol (α-TOH) is a promising monoterpenoid detaining several biological activities. However, as a volatile molecule, the incorporation of α-TOH within formulated products poses several challenges related to its stability. In this sense, nanoencapsulation works as a key technology to protect the bioactivity of low molecular weight oils, like α-TOH, against environmental stresses (heat, light, and moisture), mitigating their susceptibility to degradation (oxidation and volatilization). Physical properties of encapsulated flavor/essential oil have been extensively reported, whereas there is a lack in the literature regarding their chemical stability, which is usually the main purpose of encapsulation. Thus, in this study, the physicochemical stability of the formulated oil-in-water nanoemulsion loaded with α-TOH stabilized with Quillaja saponins (QSs) as a natural emulsifier (α-TOH-QSs-NE) were tracked in a long-term (up to 280th day). Along with time, mean droplet diameter (MDD) and turbidity were used as a reference for physical parameters; while the chemical stability was monitored using gas chromatography analysis to quantify the mark content of α-TOH into the NE. Results indicated that α-TOH-QSs-NE was successfully formulated with a high-load amount of α-TOH (90 mg mL-1). α-TOH-QSs-NE showed great physicochemical stability regardless the storage-temperature (5 °C or 25 °C) up to 280th day, with no significant alterations in the MDD or turbidity, where c.a. 79% of the initial amount of the nanoemulsified α-TOH remained detectable in α-TOH-QSs-NEs, with no finding of degradation products. Thus, the data here disclosure may be useful for innovative application of α-TOH in foodstuffs.

Physicochemical stability and in-vitro bioaccessibility of concentrated γ-Oryzanol nanodispersions fabricated by solvent displacement method.

Concentrated γ-Oryzanol nanodispersions were fabricated using milli-Q water (no emulsifier) or 0.1% (w/w) polysorbate 80 (T80), modified lecithin (ML) or sodium caseinate (SC) as emulsifiers. The freshly prepared nanodispersions had comparable particle diameter (118 to 157 nm), γ-Oryzanol concentration (1.75 to 1.92 mg mL-1) and free-radical scavenging activity (59 to 62%) and had negative ζ-potentials (-22 to -59 mV), indicating that both γ-Oryzanol and emulsifier coexisted on the particles' interface. The nanoparticles had superior physicochemical stability up to 30 days of storage at 5 °C and were successfully autoclaved without excessive growth or aggregation. Nevertheless, they showed distinct physical stability upon storage at specific environmental conditions, which affected their In-vitro gastrointestinal digestion. Comprehensively, emulsifier-free nanodispersions were sensitive to acidic pH, NaCl and CaCl2 addition. ML and SC coated nanoparticles were sensitive to Ca2+ ions, while T80 stabilized nanodispersions resisted to all environmental stresses, resulting in optimal simulated intestinal absorption.

Essential-Oil-Loaded Nanoemulsion Lipidic-Phase Optimization and Modeling by Response Surface Methodology (RSM): Enhancement of Their Antimicrobial Potential and Bioavailability in Nanoscale Food Delivery System.

Nanoencapsulation is an attractive technique used for incorporating essential oils in foods. Thus, our main goal was to formulate a novel nanoemulsion (NE) with nanoscale droplet size and lowest interfacial tension in the oil-water interface, contributing positively to the stability and the enhancement of essential oil potential. Thereby, response surface methodology (RSM), with mixture design was used to optimize the composition of the NE lipid phase. The essential oil combinations were encapsulated through high-pressure homogenization (HPH) with the binary emulsifier system (Tween 80: Gum Arabic). Then, the electrophoretic and physical properties were evaluated. We also conducted a follow-up stability and antimicrobial study that examined the stabilization mechanism of optimal NE. Thereafter, the effect of nanoencapsulation on the essential oil composition was assessed. The RSM results were best fitted into polynomial models with regression coefficient values of more than 0.95. The optimal NE showed a nanometer-sized droplet (270 nm) and lower interfacial tension (~11 mN/m), favoring negative ζ-potential (-15 mV), showing good stability under different conditions-it synergistically enhances the antimicrobial potential. GC-MS analysis showed that the use of HPH affected the active compounds, consistent with the differences in linalool and 2-Caren-10-al content. Hence, the novel nanometric delivery system contributes to food industry fortification.

Comprehensive study of α-terpineol-loaded oil-in-water (O/W) nanoemulsion: interfacial property, formulation, physical and chemical stability.

In this study, the interfacial ability of α-terpineol (α-TOH) was reported, followed by its trapping into oil-in-water (O/W) nanoemulsion as active-ingredient and the long-term observation of this nanosystem influenced by the storage-time (410-days) and temperature (5, 25, 50 °C). The results indicated that the α-TOH can reduce the interfacial tension on the liquid-liquid interface (ΔG°m = -1.81 KJ mol-1; surface density = 8.19 × 10-6 mol m-2; polar head group area = 20.29 Å2), in the absence or presence of surfactant. The O/W nanoemulsion loaded with a high amount of α-TOH (90 mg mL-1; 9α-TOH-NE) into the oil phase was successfully formulated. Among the physical parameters, the mean droplet diameter (MDD) showed a great thermal dependence influenced by the storage-temperature, where the Ostwald ripening (OR) was identified as the main destabilizing phenomena that was taking place on 9α-TOH-NE at 5 and 25 °C along with time. Despite of the physical instability, the integrity of both nanoemulsion at 5 °C and 25 °C was fully preserved up to 410th day, displaying a homogeneous and comparable appearance by visual observation. On contrary, a non-thermal dependence was found for chemical stability, where over 88% of the initial amount of the α-TOH nanoemulsified remained in both 9α-TOH-NE at 5 and 25 °C, up to 410th day. Beyond the key data reported for α-TOH, the importance of this research relies on the long-term tracking of a nanostructured system which can be useful for scientific community as a model for a robust evaluation of nanoemulsion loaded with flavor oils.

Design of nanoemulgel using Argania spinosa microfibrillated cellulose and natural emulsifiers foreseeing melanogenesis enhancement.

Nanotechnology is a route of choice that improves administration and efficacy of bioactive compounds. In this study, nanoemulgels were prepared using microfibrillated cellulose from Argania spinosa shell (AS-MFC) and Argan shell (ASE) or Argan press cake extracts (APC) as natural emulsifiers. Oil-in-water (O/W) nanoemulsions were prepared using different natural emulsifiers or synthetic emulsifiers and presented a nano size (d3,2 < 140 nm). Following that, the nanoemulsions were incorporated within AS-MFC matrix and rheological properties confirmed a shear thinning behavior. Confocal micrographs of nanoemulgels confirmed the dispersion of nanoemulsions in the AS-MFC network without affecting the nanoemulsions stability. Finally, in vitro bioassay on B16F10 using ASE or APC nanoemulsions was conducted. This study confirmed cell permeation in B16F10 cells of formulated nanoemulsions and the upregulation of melanin content up to 30% more that the untreated cells. This study designed novel MFC nanoemulgel with high potential application in healthcare and cosmetic field.

Chitosan-based film incorporated with essential oil nanoemulsion foreseeing enhanced antimicrobial effect.

Foodborne diseases are a huge problem that causes dramatic economic losses and threatens consumers' lives. Chitosan-based film incorporated with essential oil nanoemulsion would be an ideal solution to build smart food packaging. Thyme oil was formulated into nanoemulsion and checked for the droplet size, distribution, and physical stability. The prepared thyme oil nanoemulsion was incorporated with the chitosan-filmogenic mixture through continuous mixing. The filmogenic mixture was cast, dried, and assessed for their morphological, physical, mechanical, and molecular properties. In addition to investigating the antimicrobial activity against gram-negative (Escherichia coli spp.) and gram-positive (Bacillus subtilis spp.) bacteria. Thyme oil nanoemulsion showed a small droplet size (89-90 nm) with considerable stability. Incorporating thyme oil nanoemulsion with the chitosan-based film did not cause great change in the film appearance and transparency, while enhanced the light barrier property. It caused noticeable changes to the film physical (ex., moisture content, water vapor permeability, among others) and mechanical (Tensile strength and elongation at break) properties. On the other hand, it improved the film thermal stability without causing a structural alteration in the film matrix. Incorporation of chitosan-based film with thyme nanoemulsion remarkably improved the antimicrobial activity against foodborne pathogens. Chitosan-based film incorporated with thyme oil nanoemulsion would be considered a promising antimicrobial food packaging material with considerable packaging properties, and substantial growth inhibitor of foodborne pathogens.

Argan (Argania Spinosa) press cake extract enhances cell proliferation and prevents oxidative stress and inflammation of human dermal papilla cells.

BACKGROUND: Hair follicle undergoes a growth cycle under the regulation of dermal papilla cells. Due to their enormous roles, these fibroblast cells have been used in various in vitro studies as a screening model to evaluate the effect of hair growth regulating agents. OBJECTIVE: In the current study, we aim to check the hair growth potential effect of Argan press cake (APC) extracted using 50 or 80 % aqueous ethanol on human hair follicle dermal papilla cells (HFDPCs) and to determine the molecular mechanism. METHODS: APC were applied to HFDPCs, then cell proliferation assays, mitochondrial biogenesis assay, and oxidative stress assay were assessed. DNA microarray was performed from the cells treated with our samples and minoxidil. Validation of the results was done using Quantitative Real-Time PCR with primers for hair-growth related genes. GC/MS analysis was used to determine the compounds contained in APC 50 and 80 %. RESULTS: APC enhanced cell proliferation along with the stimulation of the ATP content. Additionally, APC had an anti-oxidant activity against H2O2 mediated oxidative stress preventing dermal papilla cell senescence. Consistent with this, global gene profiling analysis showed an activation of hair growth-related pathway, and a downregulation of inflammation- and oxidative stress-related genes by APC extracts. GC/MS analysis revealed that these extracts contained pure fatty acids, derived sugar chains, and pure compounds including tocopherols, squalene, and spinasterol. CONCLUSION: Taken together, here we showed that APC extracts had an effect on stimulating hair growth while inhibiting the inflammation and the oxidative stress of HFDPCs and thus can potentially contribute to an anti-hair loss drug development.

Influences of Technological Parameters on Cross-Flow Nanofiltration of Cranberry Juice.

The paper focused on the influence of operative conditions on the separation of benzoic acid from 10 °Brix cranberry juice by cross-flow nanofiltration with a plate and frame pilot scale (DDS Lab Module Type 20 system). Six kinds of commercial nanofiltration membrane were investigated. The results showed that the rejection of benzoic acid was significantly lower than that of other components in cranberry juice, including sugars and other organic acids. In a range of 2-7.5 L/min, feed flow rate slightly affected the performance of nanofiltration. Higher temperatures resulted in higher permeate flux and lower rejection of benzoic acid, whereas rejection of sugar and organic acid was stable at a high value. In a range of 2.5-5.5, pH also significantly affected the separation of benzoic acid and negative rejection against benzoic acid was observed at pH 4.5 with some of the membranes. This implies that pH 4.5 is considered as an optimum pH for benzoic acid separation from cranberry juice. The lower permeate flux caused a lower rejection of benzoic acid and negative rejection of benzoic acid was observed at the low permeate flux. Pretreatment by ultrafiltration with CR61PP membranes could improve the permeate flux but insignificantly influenced the efficiency of separation. The results also indicated that NF99 and DK membranes can be effectively used to separate benzoic acid from cranberry juice.

Formulation, physicochemical characterization, and anti- E. coli activity of food-grade nanoemulsions incorporating clove, cinnamon, and lavender essential oils.

This research studies the application of a specific nanoemulsion as anti-Escherichia coli agent. The specific mixture was generated by a simplex-centroid design. Physicochemical parameters such as droplet average diameter, pH, viscosity, density, turbidity, whitening index, refractive index, stability (thermal, physical, and osmotic stability), and antibacterial activity kinetic, have been assessed. The mixture nanoemulsions had droplet diameters significantly smaller than those of clove or cinnamon nanoemulsions. Individual and mixture essential oils nanoemulsion exhibited appropriate stability under pH, thermal, and ionic stress as well as after mid-term storage. Antibacterial activity kinetic revealed the fast and pronounced efficacy of mixture nanoemulsions on E. coli (reach 98% of growth inhibition), especially for the nanoemulsion composed of 50% essential oil in the dispersed phase upon 20 days of storage. All data considered, the actual work evidences the promising advantages of using specific nanoemulsions as delivery systems of antibacterial agents in the beverage and food industry.

Interfacial and emulsifying properties of purified glycyrrhizin and non-purified glycyrrhizin-rich extracts from liquorice root (Glycyrrhiza glabra).

This study compared the interfacial and emulsifying properties of purified saponins and non-purified saponin-rich extracts of Glycyrrhiza glabra, and highlighted potential mechanisms by which crude surface-active compositions, such as liquorice root extract (LRE), act as emulsifiers. LRE presented different fluid properties, in comparison to purified glycyrrhizin (PG), at equivalent glycyrrhizin concentrations. Particularly, it exhibited limited glycyrrhizin fibrilization at pH < pKa and efficiently reduced the interfacial tension at the soybean oil/water interface, independently of pH. LRE also presented better emulsification properties, in comparison to PG samples. Emulsions prepared using LRE had lower droplet sizes when using higher oil mass fractions or lower homogenization pressures, which was attributed to 2 main factors: (i) efficient adsorption of glycyrrhizin molecules at relatively low interfacial curvatures, thus accelerating oil phase breakup during homogenization and (ii) sufficient coverage of newly generated droplets due to adsorption of residual surface-active components (e.g. proteins), thus minimizing droplet coalescence.