Influence of the welan gum biopolymer concentration on the rheological properties, droplet size distribution and physical stability of thyme oil/W emulsions

Pentacyclic triterpene-loaded emulsion stabilized by Agaricus blazei Murill polysaccharides: Factorial design and cytoprotection study

In this study, pentacyclic triterpene-loaded emulsions were stabilized by polysaccharides from Agaricus blazei Murill mushroom (PAb). The drug-excipient compatibility results by Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) showed the absence of physicochemical incompatibilities. The use of these biopolymers at 0.75 % led to obtaining emulsions with droplets smaller than 300 nm, moderate polydispersity, and ζ-potential >30 mV in modulus. The emulsions presented high encapsulation efficiency, suitable pH for topical application, and absence of macroscopic signs of instability during 45 days. Morphological analysis suggested the deposition of thin layers of PAb around the droplets. The encapsulation of pentacyclic triterpene in emulsions, stabilized by PAb, improved the cytocompatibility of this drug against PC12 and murine astrocyte cells. There was a reduction in cytotoxicity, which resulted in a lower accumulation of intracellular reactive oxygen species and maintenance of the mitochondrial transmembrane potential. Based on these results, it is estimated that PAb are promising biopolymers for the emulsions' stabilization by improving their physicochemical and biological properties.

Effects of high acyl gellan gum on the rheological properties, stability, and salt ion stress of sodium caseinate emulsion

Sodium caseinate (SC) is widely used as a biological macromolecular emulsifier in oil-in-water (O/W) emulsions. However, the SC-stabilized emulsions were unstable. High-acyl gellan gum (HA) is an anionic macromolecular polysaccharide that improves emulsion stability. This study aimed to investigate the effects of HA addition on the stability and rheological properties of SC-stabilized emulsions. Study results revealed that HA concentrations >0.1 % could increase Turbiscan stability, reduce the volume average particle size, and increase the zeta-potential absolute value of the SC-stabilized emulsions. In addition, HA increased the triple-phase contact angle of SC, transformed SC-stabilized emulsions into non-Newtonian fluids, and effectively inhibited the movement of emulsion droplets. The effect of 0.125 % HA concentration was the most effective, allowing SC-stabilized emulsions to maintain good kinetic stability over a 30-d period. NaCl destabilized SC-stabilized emulsions but had no significant effect on HA-SC emulsions. In summary, HA concentration had a significant effect on the stability of SC-stabilized emulsions. HA altered the rheological properties and reduced creaming and coalescence by forming a three-dimensional network structure, increasing the electrostatic repulsion of the emulsion and the adsorption capacity of SC at the oil-water interface, and thereby improving the stability of SC-stabilized emulsions during storage and in the presence of NaCl.

The effect of periodate oxidation of basil seed gum and its addition on protein binding

This study attempted to determine the best point of basil seed oxidation by applying response surface methodology (RSM) with 3 factors of temperature (35-45 °C), pH (3-7) as well as time (3-7 h), at 3 levels. The produced dialdehyde basil seed gum (DBSG) was collected and its physicochemical properties were determined. Fitting of quadratic, linear polynomial equations was subsequently done by considering the insignificant lack of fit, as well as highly considerable R², in order to probe the probable relationship existing between these considered variables as well as the obtained responses. So the considered optimal related test conditions, which included pH = 3, T = 45 °C as well as Time = 3 h, were specified to produce the highest percentage of aldehyde (DBSG32), optimal (DBSG34) and the (DBSG74) samples with the highest viscosity. The results obtained by FTIR and aldehyde content determination provided the indication that dialdehyde groups were formed in a way that was in equilibrium with the considered the hemiacetal form which was dominant. Furthermore, AFM investigation related to the considered DBSG34 sample displayed over-oxidation as well as depolymerization; this might be due to the enhanced hydrophobic qualities, as well as the decreased viscosity. While the DBSG34 sample had the most dialdehyde factor group with a particular tendency for the combination having the proteins' amino group, DBSG32 and DBSG74 samples could be desirable for industrial uses owing to no overoxidation.

Influence of nanoemulsion/gum ratio on droplet size distribution, rheology and physical stability of nanoemulgels containing inulin and omega-3 fatty acids

BACKGROUND

New consumer habits are forcing the food industry to develop new and healthy products. In response to this tendency, in this investigation, we obtained nanoemulgels by microfluidization containing inulin fibre and omega-3 fatty acids. First, the influence of the number of microfluidization cycles on the physical properties of the nanoemulsions was studied. Subsequently, an advanced-performance xanthan gum was added to the nanoemulsion in different nanoemulsion/xanthan ratios (1:1, 2:1, 3:1, 4:1, 1:2, and 1:3).

RESULTS

Laser diffraction, multiple light scattering, and rheology techniques were used to characterize nanoemulsions and the corresponding nanoemulgels. The nanoemulsion with the lowest Sauter mean diameter (138 nm) and the longest physical stability was obtained after three passes through a microfluidization device at a fixed pressure of 103 421 kPa. Thus, these processing conditions were always used to obtain the nanoemulsion; these were subsequently mixed with a xanthan gum solution to produce nanoemulgels that showed weak gel-like viscoelastic and shear-thinning flow behaviours. A decrease in the nanoemulsion/xanthan ratio (i.e. by an increase in the content of xanthan gum in the nanoemulgel) increased the viscoelastic moduli and the zero shear viscosity values. A rise in the droplet size was observed with aging time, probably due to flocculation. The nanoemulsion/xanthan gum mass ratio of 1:3 yielded the most stable nanoemulgel.

CONCLUSIONS

This work is a contribution to the development of functional foods. It has been demonstrated that it is possible to obtain a stable nanoemulgel-based food matrix containing fibre and omega-3 fatty acids. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

A review on the physicochemical and biological applications of biosurfactants in biotechnology and pharmaceuticals

Biosurfactants are the chemical compounds that are obtained from various micro-organisms and possess the ability to decrease the interfacial tension between two similar or different phases. The importance of biosurfactants in cosmetics, pharmaceuticals, biotechnology, agriculture, food and oil industries has made them an interesting choice in various physico-chemical and biological applications. With the aim of representing different properties of biosurfactants, this review article is focused on emphasizing their applications in various industries summarizing their importance in each field. Along with this, the production of recently developed chemically and biologically important biosurfactants has been outlined. The advantages of biosurfactants over the chemical surfactants have also been discussed with emphasis on the latest findings and research performed worldwide. Moreover, the chemical and physical properties of different biosurfactants have been presented and different characterization techniques have been discussed. Overall, the review article covers the latest developments in biosurfactants along with their physico-chemical properties and applications in different fields, especially in pharmaceuticals and biotechnology.

Elaboration and characterization of nanoemulsion with orange essential oil and pectin

BACKGROUND

Nanoemulsions formulated with citric essential oils are currently of interest because of their physical and chemical properties and multiple applications in areas such as the food industry or agrochemicals. These are thermodynamically unstable and have almost Newtonian flow behaviour, but a suitable formulation allows systems to be obtained with good physical stability and rheological properties. The addition of pectin makes this possible. In this work, food nanoemulsions formulated with pectin, orange essential oil (5 wt%), and Tween 80 were obtained by microfluidization. First, the effect of Tween 80 concentration from 1 to 5 wt% on emulsions without pectin was evaluated. Then, pectin was added to the most stable nanoemulsion obtained and two variables were studied: the pectin solution concentration (from 2 to 6 wt%) and the pectin/emulsion ratio (1:1 or 2:1) at a fixed pectin concentration.

RESULTS

Rheological, laser diffraction, and multiple light scattering techniques were employed to determine the content of Tween 80 that results in the most stable nanoemulsion without pectin, which was 3 wt%. In addition, these techniques were used to determine the structure and physical stability of the nanoemulsions containing orange essential oil and pectin. The results obtained showed that the emulsions containing 2 wt% pectin were destabilized before 24 h. Furthermore, the emulsion with 6 wt% pectin and a 2:1 pectin/emulsion ratio showed the highest viscosity and the lowest mean diameters, and therefore the greatest stability.

CONCLUSION

This work extends the knowledge of formulation of nanoemulsions and using essential oils. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Dual encapsulation of β-carotene by β-cyclodextrin and chitosan for 3D printing application

Dual encapsulation of β-carotene (CAT) by β-cyclodextrin (CCLD) and chitosan (CS) are prepared via self-assembly process by special addition order and concentration. CCLD and CS alone could not effectively stabilize CAT, while CAT could be encapsulated in cavity of CCLD and the inclusion complex could be further strengthened by CS, due to hydrogen-bonding between CCLD and CS via groups including NH₂ and OH. The dispersion system based on dual encapsulation of CAT had outstanding shear-thinning behavior, proper pseudoplastic properties, satisfactory yield stress, excellent thermal stability and great thixotropy, illustrating high potential for 3D printing. 3D printing of CAT-encapsulated system with high-content CS on paper and bread proves its excellent extrudability and printability, with possible potential in nutrition personalization. The designed host encapsulation structure by CCLD and CS plays a guiding role in incorporating functional materials including bioactives, probiotics, enzymes, vitamins, etc., and provides a reference in innovative food technology.

Relation between Droplet Size Distributions and Physical Stability for Zein Microfluidized Emulsions

Zein, a subproduct of the food industry and a protein, possesses limited applications due to its high hydrophobic character. The objective of this research was to investigate the influence of homogenization pressure and cycles on the volumetric mean diameter (D_4,3), span values, and Turbiscan Stability Index (TSI) using the response surface methodology for microfluidized emulsions containing zein as a unique stabilizer. Results showed that homogenization pressure seems to be the most influential parameter to obtain enhanced physical stability and droplet size distributions, with the optimum being 20,000 psi. Interestingly, the optimum number of cycles for volumetric diameter, span value, and TSI is not the same. Although a decrease of D_4,3 with number of cycles is observed (optimum three cycles), this provokes an increase of span values (optimum one cycle) due to the recoalescence effect. Since physical stability is influenced by D_4,3 and span, the minimum for TSI is observed at the middle level of the cycles (2 cycles). This work highlights that not only volumetric diameter, but also span value must be taken into consideration in order to obtain stable zein emulsions. In addition, this study wants to extend the limited knowledge about zein-based emulsions processed with a Microfluidizer device.

Weilan gum oligosaccharide ameliorates dextran sulfate sodium‑induced experimental ulcerative colitis

Ulcerative colitis (UC) is a global disease, characterized by periods of relapse that seriously affects the quality of life of patients. Oligosaccharides are considered to be a prospective strategy to alleviate the symptoms of UC. The present study aimed to evaluate the effect of weilan gum oligosaccharide (WLGO) on a mouse UC model induced by dextran sulfate sodium (DSS). WLGO structural physical properties were characterized by electrospray mass spectrometry and fourier tansform infrared spectroscopy. MTT assays were performed to evaluate the non‑toxic concentration of WLGO. RT‑qPCR and ELISAs were conducted to determine the levels of inflammatory factors. The clinical symptoms and mucosal integrity of the DSS‑induced UC model were assessed by DAI and histological assessment. LPS‑induced Caco‑2 cells and DSS‑induced UC mice were used to explore the effects of WLGO on UC. Treatment of the mice with 4.48 g/kg/day WLGO via gavage for 7 days significantly relieved the symptoms of DSS‑induced UC model mice, whereas significant effects were not observed for all symptoms of DSS‑induced UC in the WLGO‑low group. The disease activity index score was decreased and the loss of body weight was reduced in DSS‑induced UC model mice treated with WLGO. Moreover, colonic damage and abnormally short colon length shortenings were relieved following WLGO treatment. WLGO treatment also reduced the concentration and mRNA expression levels of proinflammatory cytokines, including interleukin‑1β, interleukin‑6 and tumor necrosis factor α, in DSS‑induced UC model mice and lipopolysaccharide‑treated Caco‑2 cells. These results indicated that WLGO may be an effective strategy for UC treatment.

Effects of acetylated cassava starch on the physical and rheological properties of multicomponent protein emulsions

The present study investigates the effect of different acetylated cassava starch (ACS) concentrations on the physical and rheological properties of multicomponent emulsion-based products at specific pH values. The emulsion-based products were made by mixing 2% (w/v) prepared lipid droplets that were stabilized by either native or heated whey proteins, 0.01% (w/v) flaxseed gum and 0-6.0% (w/v) ACS. The results indicated that particle size, apparent viscosity and rheological moduli of multicomponent emulsion-based products were significantly enhanced with increasing addition amounts of ACS (P < 0.05). Moreover, the microscopic morphology showed that the addition of ACS contributed to the formation of a more compact, uniform, and continuous comb-like network. However, higher ACS concentration was prone to induce visibly larger aggregations and coarser textures, lending to some negative impact on visual appearance and overall acceptability. Moreover, acidic conditions could obviously promote droplet aggregation via electrostatic interactions, whereas neutral conditions had no effect on droplet aggregation. Additionally, when compared with native whey proteins, lipid droplets stabilized by their heated protein forms induced significantly higher apparent viscosities and rheological moduli of multicomponent emulsion-based products (P < 0.05). Our results potentially provide some information for the creation of multicomponent emulsion-based products with various desirable quality attributes.

Optimizing the properties of Zodo gum and examining its potential for amino acid binding by periodate oxidation

In this study, the Zodo gum exudated by Amygdalus scoparia spach underwent the periodate oxidation process for chemical modification and the formation of dialdehyde groups. Modification of the Zodo gum properties was done using the periodate oxidation method, response surface methodology (RSM) and central composite design (CCD), with 4 factors of sodium periodate volume (6.4-19.2 mL), temperature (35-55 °C), pH (3-5) and time (2-4 h). Dialdehyde Zodo gum (DZG) was produced by controlling test variables and measuring some responses including dialdehyde content and efficacy, in addition to evaluating the rheological parameters. Quadratic, linear polynomial equations were then fitted with the insignificant Lack of fit and high R² to address the relationship between the mentioned variables and responses. Optimal test conditions, including pH = 3.9, T = 43 °C and Time = 3.5 h, were also determined for the production of DZG₁₀, DZG₂₀ and DZG₃₀ samples. The results of ¹H-¹³C NMR, FTIR and determination of the aldehyde content indicated the formation of dialdehyde groups in equilibrium with the dominant hemiacetal form. The AFM study of the DZG₃₀ sample also showed over-oxidation and depolymerization, which could be associated with increased hydrophobic properties and the reduced viscosity. Although the DZG₃₀ sample had the highest amount of the dialdehyde factor group with the tendency to combine with the amino group of proteins, DZG₁₀ and DZG₂₀ samples could be recommended for industrial applications due to the nonoccurrence of overoxidation.

Rheological behaviors of a novel exopolysaccharide produced by Sphingomonas WG and the potential application in enhanced oil recovery

A novel exopolysaccharide, named WL gum, was obtained from the fermentation broth of Sphingomonas sp. WG. The effects of temperature and salinity on the rheological properties of WL gum solution and fermentation broth (WL-Fer) were systematically investigated and compared with another exopolysaccharide, welan gum (WG). The results showed that the network structures formed in WL solution were more compact than those of WG. WL solution and WL-Fer were not sensitive to high temperatures (80-120 °C) and only weakly affected by the cations (Na⁺, K⁺, and Ca²⁺). Moreover, Fe²⁺ and high temperature (100 °C) even enhanced the viscosity of WL-Fer. The results of flooding experiments demonstrated that the enhanced displacement efficiency of WL gum (14.55%) was similar to that of partially hydrolyzed polyacrylamide (HPAM, 13.36%) at 65 °C. And the enhanced displacement efficiency of WL-Fer was as high as 23.31%. It can be concluded that WL gum is a kind of potential and environmentally benign polymer that could be used in EOR, and the fermentation broth could be used directly after dilution.

Impact on stabilization of ionic gum emulsions by natural and thermally modified Chironji gum

Ionic gums like acacia and tragacanth are known for their emulsifying properties but lower viscosity limits its use. This study explores the effects of natural chironji gum and its thermally modified form on the emulsifying properties of acacia and tragacanth. Formulations of chironji gum (CG) O/W emulsion FA1-FA4 were prepared with acacia and FT1-FT4 with tragacanth respectively. Heat treated gums(CGTs) were obtained by heating CG at 110 °C for time intervals 24 h, 48 h and 96 h. Similarly formulations FHA1-FHA12 and FHT1-FHT12 were prepared with acacia and tragacanth replacing CG with heat treated gums. Heat treated gum formulations showed better stabilizing properties than natural CG emulsions. The FA1-FA4 and FT1-FT4 formulations had droplet size in the range of 9.77-26.55 μm and zeta potential ranging from -14.8 mV to -23.2 mV. In contrast, the droplet size and zeta potential of FHA1-FHA12 and FHT1-FHT12 were in range of 1.42-17.5 μm and -17.2 mV to -40.6 mV respectively signifying improved stabilizing capacity of CGT gums. The droplet size and zeta potential of these formulations remained stable even after 7 days of storage at room temperature with no visible phase separation of the formulation observed for more than a month.

Characterization of novel nanoemulsions, with improved properties, based on rosemary essential oil and biopolymers

BACKGROUND

Nowadays, it is of great interest to develop stable and sustainable formulations that act as nanocarriers of active ingredients. In this work, the droplet size distribution, rheology and physical stability of nanoemulsions with improved properties containing rosemary essential oil and biopolymers as a function of the concentration of these polysaccharides were investigated.

RESULTS

Mean diameters below 150 nm were achieved, indicating nanostructures were obtained. Regardless of gum type, a gel-like structure and a shear thinning behaviour was achieved. In addition, an increase of G', G″ and viscosity and a decrease of J₀ , J₁ , J₂ , λ₁ and λ₂ with increasing gum concentration were observed, due to the formation of a three-dimensional network in the aqueous phase. Slight differences between nanoemulsions containing welan or xanthan were found. Creaming, depletion flocculation and gel aggregation were the main destabilization processes at low, intermediate and high gum concentration, respectively. A 0.4 wt% gum nanoemulsion exhibited the best physical stability.

CONCLUSION

These stable and sustainable nanoemulsions with improved rheological properties contribute to the development of biodegradable and non-toxic food or agrochemical products. © 2020 Society of Chemical Industry.