Effect of ultrasonic power on delivery of quercetin in emulsions stabilized using octenyl succinic anhydride (OSA) modified broken japonica rice starch.

In this study, emulsions stabilized by octenyl succinic anhydride-modified broken japonica rice starch (OSA-BJRS) were prepared at different ultrasonic power intensities for the delivery, controlled release, and improved bioavailability of quercetin. The OSA-BJRS emulsions ultrasonicated at 400 W exhibited the highest encapsulation efficiency (89.37 %) and loading efficiency (58.34 %) of quercetin, the smallest volume-average droplet diameter (0.51 µm) and polydispersity index (0.19), the highest absolute value of the ζ-potential (26.73 mV), and the highest apparent viscosity and viscoelasticity. The oxidation stability, storage stability, thermal stability, and salt ion stability of the emulsions were also notably improved by the ultrasonication treatment. In addition, the results of the simulated in vitro digestion demonstrated that the ultrasonicated OSA-BJRS emulsions had an enhanced quercetin delivery performance and could stably transport quercetin to the small intestine for digestion. The OSA-BJRS emulsion ultrasonicated at 400 W exhibited the highest cumulative release rate (95.91 %) and the highest bioavailability (30.48 %) of quercetin. This suggests that OSA-BJRS emulsions prepared by ultrasonication can be considered effective delivery systems for hydrophobic functional components.

Fabrication and characterization of dual-functional porous starch with both emulsification and antioxidant properties.

Starchy materials with good antioxidant, emulsification and adsorption properties have potential applications in industry. To improve these properties, a Dual-functional porous starch was prepared through one-pot synthesis. In this case, octenyl succinic anhydride (OSA) and syringic acid (SA) were selected to modify the porous starch (PS) by esterification, with subsequent signals recorded by 1H NMR at 1.2 ppm and FT-IR at 1743 cm-1, indicating the formation of Dual-functional porous starch grafted by OSA and SA. N2 adsorption analysis further proved that the porous structure (2.9 m2g-1) was still maintained after modification. This was followed by measurements of droplet size distribution (34.18 ± 3.80 µm), zeta potential (-39.62 ± 1.89 mV) and emulsion index (85.10 ± 1.76 %), all of which indicated good emulsifying capacity. Meanwhile, results of radical scavenging assay proved that the Dual-functional porous starch had considerable antioxidant properties due to the introduction of SA groups. Besides, the Dual-functional porous starch also showed good resistance to digestion. These findings not only provide a novel strategy for constructing multi-functionalized starchy materials, but also open up potential applications of starch in the food and pharmaceutical industries.

Influence of the structure and physicochemical properties of OSA modified highland barley starch based on ball milling assisted treatment.

This study aimed to investigate the influence of ball milling assisted treatment on the degree of substitution of octenyl succinic anhydride (OSA) modified highland barley starch (HBS) and on the physicochemical properties and structure of HBS. Scanning electron microscopy (SEM) findings showed that with the increasing of ball milling time, the surface morphology of OSA modified HBS became rougher and rougher and the particle morphology and crystal structure were damaged. When the pretreatment time of ball milling was 40 min, the degree of substitution of OSA modified HBS was 1.32 times higher than that of the conventional modification method. In addition, the longer the ball milling assistant, the longer the short-range ordering of the OSA modified HBS significantly decreased, and the relative crystallinity decreased (from 16.68 % to 7.93 %), leading to a decrease in thermal stability too. However, it greatly enhanced the aging resistance and flowability. In terms of emulsification properties, the emulsification properties of OSA modified HBS increased from 60.67 % to 75.67 %. Therefore, the HBS with better freeze-thaw stability and higher degree of substitution can be prepared by ball milling pretreatment and OSA modification, which provides technical support for further development of starch resources.

Resveratrol-loaded octenyl succinic anhydride modified starch emulsions and hydroxypropyl methylcellulose (HPMC) microparticles: Cytotoxicity and antioxidant bioactivity assessment after in vitro digestion.

Hydroxypropyl methylcellulose (HPMC)-based microparticles and modified starch emulsions (OSA-MS) were loaded with resveratrol and characterized regarding their physicochemical and thermal properties. Both delivery systems were subject to an in vitro gastrointestinal digestion to assess the bioaccessibility of resveratrol. In addition, cell-based studies were conducted after in vitro digestion and cytotoxicity and oxidative stress were assessed. HPMC-based microparticles displayed higher average sizes (d) and lower polydispersity index (PDI) (d = 948 nm, PDI < 0.2) when compared to OSA-MS-based emulsions (d = 217 nm, PDI < 0.3). Both proved to protect resveratrol under digestive conditions, leading to an increase in bioaccessibility. Resveratrol-loaded HPMC-microparticles showed a higher bioaccessibility (56.7 %) than resveratrol-loaded emulsions (19.7 %). Digested samples were tested in differentiated co-cultures of Caco-2 and HT29-MTX, aiming at assessing cytotoxicity and oxidative stress, and a lack of cytotoxicity was observed for all samples. Results displayed an increasing antioxidant activity, with 1.6-fold and 1.4-fold increases over the antioxidant activity of free resveratrol, for HPMC-microparticles and OSA-MS nanoemulsions, respectively. Our results offer insight into physiological relevancy due to assessment post-digestion and highlight the protection that the use of micro-nano delivery systems can confer to resveratrol and their potential to be used as functional food ingredients capable of providing antioxidant benefits upon consumption.

Functionality differences between esterified and pregelatinized esterified starches simultaneously prepared by octenyl succinic anhydride modification and its application in dough.

Octenyl succinic anhydride (OSA)-modified starches have gained widespread interest, but the modification can produce two starches with different states ignored. Herein, the two types of starches, esterified starch (ES) and pregelatinized esterified starch (PES), prepared by OSA modification were separated, and their structural and functional characteristics were comprehensively explored. Results showed that compared with native starch (NS), ES and PES exhibited high water-holding capacity, solubility, and swelling power and significantly decreased pasting temperature and thermal stability. Dynamic rheological tests illustrated that OSA modification changed the rheological behavior of starches. Fourier transform infrared spectroscopy confirmed that PES with higher degree of substitution showed more obvious ester carbonyl and carboxylate groups than ES. Laser confocal micro-Raman spectroscopy revealed that the short-range molecular order of ES, especially PES, decreased after modification. X-ray diffraction indicated that OSA modification disrupted the crystalline structure of starch, and that more amylose-lipid complex was formed in PES. Scanning electron microscopy showed that OSA modification eroded starchs surface and reduced its smoothness, and significantly disrupted PES integrity. ES and PES could be developed as food additives for retrogradation inhibition of dough. These results provide new insights into OSA modification and expand its functional application in foods.

Properties of OSA-esterified insoluble fraction of Persian gum and its application in dairy cream.

BACKGROUND: In the present study, the insoluble fraction of Persian gum (IFPG) was modified with octenyl succinic anhydride (OSA) and its various properties were assessed. In addition, the effect of OSA-IFPG on the rheological and textural properties of dairy cream was investigated. RESULTS: Suitable conditions for achieving a degree of substitution (DS) of 0.023 were found at pH 9, IFPG concentration 4 wt%, OSA concentration 10 wt% and a temperature of 40 °C, within 120 min. The carbonyl group attachment in OSA-IFPG was also confirmed via Fourier transform infrared and H-nuclear magnetic resonance spectroscopy (1 H-NMR). While the X-ray diffraction test indicated no significant changes in the structure of the IFPG after modification with OSA, esterification increased the negative charge density, decreased thermal decomposition temperature and increased the emulsifying capacity to 100%, which was obtained for the first time. The use of OSA-modified IFPG in creams augmented the complex viscosity, loss and storage modulus, while also demonstrating the creation of a pseudo-gel network. The hardness and adhesiveness of the texture increased, which can be explained by the formation of a compact structure and reduced particle size. CONCLUSION: Overall, OSA-IFPG with hydrophilic and hydrophobic sections may function as an emulsifier and be recommended as a safe source of hydrocolloids for emulsion stability. It can also provide a positive physical structure when added to dairy cream, even if the fat concentration is lower than usual. © 2023 Society of Chemical Industry.

Differences in the structural properties of three OSA starches and their effects on the performance of high internal phase Pickering emulsions.

The emulsifying properties of emulsions are significantly influenced by the structural properties of octenyl succinic anhydride (OSA) starch. The purpose of this work was to elucidate the effect of the structure of OSA starch on its performance as an emulsifier to stabilize Pickering high-internal-phase emulsions (HIPEs). The degrees of substitution (DS) of the three OSA starches were 0.0137, 0.0177 and 0.0236, and their degrees of branching (DB) were 13.96 %, 14.20 % and 14.32 % measured by 1H NMR, which were sequentially labeled as OSA1, OSA2, and OSA3. The OSA3 starch with higher DS and DB had a lower critical micelle concentration (CMC) (0.11 mg/mL). Its emulsification activity (EAI) and emulsion stability (ES) were 61.8 m2/g and 72.5 min, respectively, which were higher than OSA1 and OSA2 starches. The contact angle of the three OSA starches increased from 45.35° to 80.03° with increasing DS and DB. Therefore, it is hypothesized that OSA3 starches have better emulsification properties. The results of physical stability of HIPEs confirmed the above results. These results indicated that DS and DB have a synergistic effect on emulsion properties, and OSA starch with higher DS and DB values were more conducive to the construction of stable HIPEs systems.

Development of Emulsion Gels Stabilized by Chitosan and Octenyl Succinic Anhydride-Modified ß-Cyclodextrin Complexes for ß-Carotene Digestion and 3D Printing.

ß-cyclodextrin (ß-CD)-based emulsion gels encapsulated with nutrition for three-dimensional (3D) printing are promising, while obstacles such as low bioaccessibility of bioactive compounds and the molding process in food manufacturing hinder their application. This study intended to develop stable composite emulsion gels using the complexes of chitosan (CS) and octenyl succinic anhydride (OSA)-modified ß-CD (OCD) to conquer these challenges. The esterification of OSA generated more negatively charged OCD and ester groups, which aided in the combination of OCD and CS through enhanced electrostatic and hydrogen bonding interactions. The addition of CS improved the emulsification properties of the complexes and acted as a bridge link in the aqueous phase, thereby increasing the gel strength of the composite emulsion gels. Moreover, the encapsulation of ß-carotene destabilized the strength of the emulsion gels by lowering the interfacial tension. The emulsion gel stabilized by OCD3/CS-0.75% at an initial pH not only successfully encapsulated ß-carotene and presented the highest bioaccessibility of 41.88 ± 0.87% in the in vitro digestion but also showed excellent 3D printability. These results provided a promising strategy to enhance the viscoelasticity of ß-CD-based emulsion gels and accelerate their application in bioactive compound delivery systems and 3D food printing.

Revisiting the Formation of Starch-Monoglyceride-Protein Complexes: Effects of Octenyl Succinic Anhydride Modification.

Starch-lipid-protein complexes are attracting increasing attention due to their unique structure and low enzymatic digestibility. However, the mechanisms underlying the formation of these ternary complexes, especially those with monoglycerides as the lipid component, remain unclear. In the present study, potato starch or octenyl succinic anhydride (OSA)-modified potato starch (OSAPS), various monoglycerides (MGs), and beta-lactoglobulin (ßLG) were used in model systems to characterize the formation, structure, and in vitro digestibility of the respective ternary complexes. Colorimetry and live/dead staining assays demonstrated that the OSAPS had good biocompatibility. Experimental data and molecular dynamics simulations showed that both unmodified potato starch and OSAPS formed starch-lipid-protein complexes with MGs and ßLG. Of the two types of starch, OSA formed a greater amount of the more stable type II V-crystallites in complexes, which had greater resistance to in vitro enzymic digestion. This study demonstrated for the first time that starch can interact with MGs and ßLG to form ternary complexes and that OSA esterification of starch promoted the formation of more complexes than unmodified starch.

Synthesis, physicochemical and emulsifying properties of OSA-modified tamarind seed polysaccharides with different degrees of substitution.

Octenyl succinic anhydride modified tamarind seed polysaccharides (OTSPs) with various degrees of substitution were first synthesized and characterized in this work. The structural, solid-state, solution and emulsifying properties of the OTSPs and the effect of the degree of substitution (DS) were investigated. The structural characterization confirmed the successful grafting of the OSA moiety into TSP and the chain extension of the OTSPs. The hydrophobicity of the modified polysaccharide molecules increased, the absolute value of the zeta potential increased, and the thermal stability decreased, which were positively or negatively correlated with the changes in DS. In contrast, the hydrolysis of polysaccharides in alkaline aqueous solution led to a decrease in molar mass and the rigidity of the molecules, which were not significantly related to DS. Particle size analysis showed that OTSPs tended to aggregate into relatively small agglomerates, which was confirmed by the results of morphological analysis. Most importantly, the instability indices of emulsions stabilized by TSP, arabic gum and OSA-starch were 0.521, 0.715, and 0.804, respectively, while for OTSPs this parameter was between 0.04 and 0.19 under the same conditions, indicating better physical stability of the OTSP-stabilized emulsions, especially for OTSP-30. Overall, OTSP has great potential as an emulsifier for oil-in-water emulsions, especially for emulsification and stabilization in food processing.

Structure and surface properties of ozone-conjugated octenyl succinic anhydride modified waxy rice starch: Towards high-stable Pickering emulsion.

In the present work, a dual-modified waxy rice starch (OOWRS) fabricated with OSA and ozone was successfully used to stabilize the O/W Pickering emulsion. The molecular structure, surface properties, and underlying stabilizing mechanism were systematically investigated. The results showed that oxidation occurring on the surface of OSA-modified waxy rice starch (OSAWRS) resulted in the presence of indentations and cracks. The relative crystallinity of starch was generally decreased with increasing degree of oxidation. Due to the introduction of carbonyl and the variation in surface structure, the hydrophobicity and acidity of OSAWRS were significantly enhanced after the ozone treatment. Remarkably, OOWRS stabilized Pickering emulsion exhibited a feature of typical O/W emulsion, and the 0.5 h and 1 h OOWRS emulsion exhibited a more uniform droplet size as well as a higher surface potential. We also noted that a weak-gel network was formed within the OOWRS emulsion system as the hydrophilic starch chains played a bridging role. Two reasons for the improved stability of the emulsion were the special gel structure and the enhanced electrical repulsion among the droplets. This research provides that ozone-conjugated OSA modification is a promising strategy for improving the emulsion ability of starch-based Pickering emulsions.

Octenyl succinic anhydride-modified amyloid protein fibrils demonstrate enhanced ice recrystallization inhibition activity and dispersibility.

Octenyl succinic anhydride (OSA) modification of amyloid proteins fibrils (APFs) was employed to improve dispersibility and ice recrystallization inhibition activity. OSA mainly reacted with the amino groups of APFs without significantly changing morphology. OSA-modified APFs (OAPFs) had lower pI, carried more negative charges, and were more hydrophobic. OSA-modification showed a pH-dependent effect on the dispersibility of fibrils. At pH 7.0, OSA-modification improved dispersibility and inhibited heat-induced gelation of fibrils at weakened electrostatic repulsion. OAPFs were more prone to aggregation with lower dispersity at acidic pH values and demonstrated stronger IRI activity than unmodified fibrils at pH 7.0. Our findings indicate OSA-modification favors the industrial application of APFs as an ice recrystallization inhibitor with enhanced dispersibility.

Preparation, characterization and in vitro digestion of octenyl succinic anhydride-modified porous starch with different degrees of substitution.

Octenyl succinic anhydride modified porous starch (OSA-PS) with degrees of substitution (DS) from 0.0123 to 0.0427 were prepared by aqueous phase method. From SEM, PS had a porous structure which showed a rough and corrosive surface after esterification with OSA. FT-IR revealed the characteristic peaks of OSA-PS at 1725 cm-1 and 1570 cm-1. From 1H NMR spectra, OSA-PS displayed extra chemical signal peaks at 0.85 ppm, 1.25 ppm and 1.96 ppm. These results fully demonstrated that OSA groups were successfully grafted onto PS. Furthermore, as DS increased, the specific surface area (5.6464 m2/g), pore volume (0.9959 × 10-2 cm3/g) and methylene blue adsorption capacity (24.3962 mg/g) of OSA-PS reached the maximum, while its relative crystallinity (26.8112 %) and maximum thermal decomposition temperature (291.96 °C) were the minimum. In vitro digestion studies showed that with the increase of DS, OSA-PS' contents of rapidly digestible starch and slowly digestible starch decreased from 9.06 % to 6.27 % and 28.38 % to 14.61 %, respectively. In contrast, its resistant starch had an increase in content from 62.56 % to 79.12%. The results provided an effective method for obtaining a double-modified starch with high specific surface area and anti-digestibility, thus broadening the industrial application of starch.

Comparative study of rheological properties and Pickering emulsion stabilizing capacity of nonenyl succinic anhydride and octenyl succinic anhydride modified amaranth starches.

Functional properties and ability to stabilize Pickering emulsions of amaranth starch with the novel nonenyl succinic anhydride (NSA) modification and the widely used octenyl succinic anhydride (OSA) modification were compared. The NSA modification was more effective in altering the rheological properties of amaranth starches. NSA-modified amaranth starch showed significantly higher peak viscosity (7.13 Pa·s at DS of 0.02209) than the OSA-modified amaranth starch (6.10 Pa·s at DS of 0.03042). The gelatinization temperature, gelatinization enthalpy, and relative crystallinity of amaranth starch were more affected by the OSA than the NSA. The Pickering emulsions stabilized with NSA-modified starches had higher stability than those with the OSA-modified starches as characterized by particle size distribution, morphological, and rheological approaches. A lower degree of substitution by NSA than by OSA is needed to achieve a similar emulsification capacity. Thus, the NSA modification could be an efficient alternative to OSA modification in tailoring physicochemical and rheological functions, as well as stabilizing Pickering emulsions.

Improving the emulsification performance of adlay seed starch by esterification combined with ultrasonication and enzymatic treatment.

In this study, superior modified starch was prepared using ultrasonic and enzymatic treatments to confirm the potential of using adlay seed starch (ASS) in Pickering emulsions. Octenyl succinic anhydride (OSA)-modified starches, such as OSA-UASS, OSA-EASS, and OSA-UEASS, were prepared using ultrasonic, enzymatic, and combined ultrasonic and enzymatic treatments, respectively. The effects of these treatments on the structure and properties of ASS were evaluated to elucidate their influence on starch modification. Ultrasonic and enzymatic treatments improved the esterification efficiency of ASS by changing its external and internal morphological characteristics and the crystalline structure to provide more binding sites for esterification. The degree of substitution (DS) of ASS modified by these pretreatments was 22.3-51.1 % higher than that of the OSA-modified starch without pretreatment (OSA-ASS). Fourier transform infrared and X-ray photoelectron spectroscopy results confirmed the esterification. Small particle size and near-neutral wettability indicated that OSA-UEASS was the promising emulsification stabilizer. The emulsion prepared using OSA-UEASS exhibited better emulsifying activity and emulsion stability and long-term stability for up to 30 days. These amphiphilic granules with improved structure and morphology were used to stabilize a Pickering emulsion.

Synthesis of octenyl succinic anhydride-modified levan and investigation of its microstructural, physicochemical, and emulsifying properties.

In this study, levan from Bacillus licheniformis NS032 was modified in an aqueous medium by octenyl succinic anhydride (OSA), and the properties of the obtained derivatives were studied. The maximum efficiency in the synthesis reaction was achieved at 40 °C and a polysaccharide slurry concentration of 30 %. Increasing the reagent concentration (2-10 %) led to an increase in the degree of substitution (0.016-0.048). Structures of derivatives were confirmed by FTIR and NMR. Scanning electronic microscopy, thermogravimetry, and dynamic light scattering analyses showed that the derivatives with degrees of substitution of 0.025 and 0.036 retained levan's porous structure and thermostability and showed better colloidal stability than the native polysaccharide. The intrinsic viscosity of derivatives increased upon modification, while the surface tension of the 1 % solution was lowered to 61 mN/m. Oil-in-water emulsions prepared with sunflower oil (10 % and 20 %) by mechanical homogenization and 2 and 10 % derivatives in the continuous phase showed mean oil droplet sizes of 106-195 µm, while the distribution curves exhibited bimodal character. The studied derivatives have a good capacity to stabilize emulsions, as they have a creaming index ranging from 73 % to 94 %. The OSA-modified levans could have potential applications in new formulations of emulsion-based systems.

Constitution and reconstitution of microcapsules with high diacylglycerol oil loading capacity based on whey protein isolate / octenyl succinic anhydride starch/ inulin matrix.

The aim of this study was to constitute microcapsule systems with high oil loading capacity by octenyl succinic anhydride (OSA) starch, whey protein isolate (WPI) and inulin (IN) substrates to provide a new method for encapsulating diacylglycerol oil. Specifically, this study characterizes the physicochemical properties and reconstitution capacity of highly oil loading diacylglycerol microcapsules by comparing the wall encapsulation capacity of the binary wall system OSA-IN, WPI-IN and the ternary wall system WPI-OSA (1:9, 5:5, 9:1)-IN for diacylglycerol oil. It was found that WPI-OSA (5:5)-IN significantly improved the water solubility of microcapsules (86.11 %) compared to OSA-IN microcapsules, and the addition of WPI made the surface of microcapsules smoother and increased the thermal stability and solubility of microcapsules; the addition of OSA enhanced the wettability of microcapsules compared to WPI-IN. In addition, WPI-OSA (5:5)-IN microcapsules have the highest encapsulation efficiency (96.03 %), high emulsion stability after reconstitution, and the smallest droplet size (212.83 nm) after 28 d. Therefore, the WPI-OSA-IN composite system is suitable for the production of highly oil-loaded microencapsulated systems with excellent reconstitution ability to expand the application of diacylglycerol oil.

Effects of the degree of substitution of octenyl succinic anhydride on the physicochemical characteristics of adlay starch.

Impact of octenyl succinic anhydride (OSA) esterification on the structural, thermal, pasting, and emulsifying characteristics of adlay starch was investigated. The degree of substitution (DS) increased significantly from 0.008 to 0.025 with increasing OSA quantity, and the bands intensity at 1724 cm-1 and 1572 cm-1 in Fourier transform infrared spectroscopy increased with increasing DS. OSA modified starch showed unaltered orthorhombic diffraction pattern and morphological structure in native adlay starch, but gelatinization temperatures and enthalpy decreased significantly. Higher DS values lowered iodine binding capacity (from 1.37 to 0.77) and a shift in the maximum absorbance wavelength toward the shortwave direction was observed (from 530 nm to 510 nm). Significant increases were observed in peak, through, breakdown and final viscosities upon OSA esterification, while the pasting temperature decreased. Furthermore, contact angles increased significantly from 27.4° to 73.4° with increasing DS, and OSA-starch exhibited superior emulsion stability. Therefore, esterification with OSA effectively modified adlay starch to meet industrial demands and enhance its functional properties.

Fabrication of octenyl succinic anhydride starch grafted with folic acid and its loading potential for doxorubicin hydrochloride.

In this study, octenyl succinic anhydride (OSA) starch with different folic acid (FA) grafting time was prepared and the degree of FA substitution at different grafting time was determined. The results of XPS quantitatively reflected the surface elemental composition of OSA starch grafted with FA. FTIR spectra further confirmed the successful introduction of FA on OSA starch granules. SEM images showed that the surface roughness of OSA starch granules was more obvious with higher FA grafting time. The particle size, zeta potential, and swelling properties were determined to study the effect of FA on the structure of OSA starch. TGA indicated that FA effectively enhanced the thermal stability of OSA starch at high temperature. The crystalline form of the OSA starch gradually transformed from A type to a hybrid A and V-type with the progress of FA grafting reaction. In addition, the anti-digestive properties of OSA starch were enhanced after grafting FA. Using doxorubicin hydrochloride (DOX) as the model drug, the loading efficiency of OSA starch grafted with FA for DOX reached 87.71 %. These results provide novel insights into OSA starch grafted with FA as potential strategy for loading DOX.

Exploring the mechanism of high hydrostatic pressure on the chemical activity of starch based on its structure and properties changes.

High hydrostatic pressure (HHP) could induce changes in the structure and properties of starch. Native corn starch was treated and octenyl succinic anhydride (OSA)-modified corn starch was prepared under different pressures (200, 350, 500 and 600 MPa) at 40℃ for 20 min. The mechanism of HHP on the chemical activity of starch was elucidated by analyzing the relationship between the changes of native starch structure and properties and the quality of OSA-modified starch. Results showed that HHP not only helped water and OSA to penetrate the starch granules but also made the structure of starch granules undergone three changes similar to mechanochemical effects. The starch granules treated by 200 MPa were in the stress stage, and the starch granules treated by 500 MPa were in the transition stage from aggregation to agglomeration. Proper pressure treatment could significantly improve chemical activity of starch and quality of OSA-modified starch.