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Food industry is concentrating on development of novel functional foods fortified/enriched with lipophilic bioactives to improve health and well-being of consumers. β-carotene (BC) and eugenol (EU) co-encapsulated flax seed oil (FSO) emulsions stabilized by octenyl succinic anhydride modified starches (OSA-MS) were spray dried to powders after the emulsification process. Microcapsules showed good dissolution behavior, high (≈90%) microencapsulation efficiency and semi-spherical morphology observed by scanning electron microscopy. A 28 days storage test at 40 °C was carried out to evaluate the effect on physicochemical properties of microcapsules. Microcapsules encapsulated by lower Mw OSA-MS-1 presented higher oxidative stability, lower moisture contents and water activity during storage compared to high Mw OSA-MS-2. Incorporation of EU played its antioxidant role and further improved the oxidative stability as well as retention of core materials. Microcapsules of OSA-MS-1 containing FSO + BC + EU exhibited the maximum retention of BC (71%), EU (84%) and α-linolenic acid (92%). This study indicated a positive role of EU as antioxidant and low Mw OSA-starch as wall material for the encapsulation of lipophilic bioactives that could be used for the development of functional foods and beverages.

β-Carotene (precursor of vitamin A) and α-tocopherol (VE) are essential fat soluble vitamins (FSV) required for better body functioning and deficiencies of these vitamins are linked to many chronic diseases. Encapsulation of FSV into nanoemulsion-based delivery systems improves their aqueous solubility, oxidative stability and bioavailability. In this study, β-carotene (BC) and VE were co-encapsulated using flax seed oil (FSO) or medium chain triglycerides (MCT) as carrier oils and octenyl succinic anhydride modified starch (Purity Gum Ultra, PGU) or Tween-80 (TW) as emulsifiers. Nanoemulsions and bulk carrier oils containing bioactives were stored for 4 weeks to assess the effect of storage temperature on physicochemical properties. Oxidation behavior of bioactives was different in emulsions compared to bulk oil systems. The degradation of FSV was higher at elevated temperature, which was more profound for BC. VE worked as antioxidant for the protection of BC in MCT-based emulsions but it did not protect BC degradation in FSO-based emulsions. However, incorporation of eugenol (EU) improved the oxidative stability as well as retention of FSV in all emulsions. Nanoemulsions containing FSV and EU stabilized by PGU showed overall higher retention of BC (≈42%) and VE (≈90%) after 4 weeks of storage at 40 °C as compared to TW. The higher stability of PGU was due to its ability to form a thicker protective layer around oil droplets. This research provides useful information regarding the simultaneous encapsulation of lipophilic bioactives for the development of functional foods and beverages.

Flax seed oil (FSO) is rich in α-linolenic acid (ALA) and its application as a functional ingredient in oil-in-water systems is limited due to its high vulnerability towards oxidation. To overcome this, flax seed oil nanoemulsions were formulated using eugenol (EUG) as a natural antioxidant and two modified starches (Purity Gum Ultra and Purity Gum 2000) as emulsifier. The effect of eugenol addition and emulsifier type on the size, charge, rheological properties and oxidative stability of nanoemulsions stored under different temperatures (4, 25 and 40 °C) for 4 weeks was investigated. Nanoemulsions containing eugenol, stabilized by Purity Gum Ultra, showed better physical and oxidative stability during storage as compared to Purity Gum 2000 stabilized emulsions. Results revealed higher % retention of ALA (66.34%) and EUG (63.20%) in Purity Gum Ultra stabilized emulsions containing FSO + EUG stored for 4 weeks at 40 °C as compared to Purity Gum 2000 stabilized emulsions containing FSO + EUG. This was attributed to the role of eugenol as antioxidant as well as the formation of a thick protective layer at interface by Purity Gum Ultra due to its higher molecular weight and density.

Tea polyphenol (TP)-loaded nanoparticles were formulated by cross-linking chitosan hydrochloride (CSH) and sulfobutyl ether-β-cyclodextrin sodium (SBE-β-CD). Inclusion complexes of TP and SBE-β-CD were initially prepared to effectively encapsulate TP in CSH-SBE-β-CD nanoparticles (CSNs). The stoichiometry of these complexes was determined to be 1:1, using epigallocatechin gallate (EGCG) as a model guest molecule, based on Job's method. The formation of EGCG-SBE-β-CD inclusion complexes was further confirmed by the fluorescence and NMR spectroscopy, and A-ring of EGCG might be included. Prior to the incorporation of TP, the formation conditions of blank CSNs was investigated, ranging from 1.2/1 to 0.75/1 CSH/SBE-β-CD mass ratio. The particle size of TP-loaded CSNs appeared to be increased with decreasing CSH/SBE-β-CD mass ratio from 1.2/1 to 0.75/1, whereas a decreased trend was obtained in the absence of TP. Regardless the presence of TP or not, the particle size increased with increasing CSH concentration. The encapsulation efficiency increased with increasing CSH concentration or decreasing CSH/SBE-β-CD mass ratio while decreased significantly with increasing TP concentration. Cross-linking between CSH and SBE-β-CD was demonstrated with FTIR analysis, and TP was mainly located in the core of CSNs. Atomic force microscopy images showed that TP-loaded CSNs were regular spherical in shape. Results indicate that CSNs can be used as a promising carrier for the encapsulation of water soluble TP.

Clove oil (CO) anionic nanoemulsions were prepared with varying ratios of CO to canola oil (CA), emulsified and stabilized with purity gum ultra (PGU), a newly developed succinylated waxy maize starch. Interfacial tension measurements showed that CO acted as a co-surfactant and there was a gradual decrease in interfacial tension which favored the formation of small droplet sizes on homogenization until a critical limit (5:5% v/v CO:CA) was reached. Antimicrobial activity of the negatively charged CO nanoemulsion was determined against Gram positive GPB (Listeria monocytogenes and Staphylococcus aureus) and Gram negative GNB (Escherichia coli) bacterial strains using minimum inhibitory concentration (MIC) and a time kill dynamic method. Negatively charged PGU emulsified CO nanoemulsion showed prolonged antibacterial activities against Gram positive bacterial strains. We concluded that negatively charged CO nanoemulsion droplets self-assemble with GPB cell membrane, and facilitated interaction with cellular components of bacteria. Moreover, no electrostatic interaction existed between negatively charged droplets and the GPB membrane.

The in vitro hypoglycemic properties of three different sulfuric acid (H 2 SO 4 ) modified rice bran insoluble fibers (SMRBIFs) produced using 0.2% (0.2%-SMRBIF), 1.25% (1.25%-SMRBIF), 2.0% (2.0%-SMRBIF) (w/v) H 2 SO 4 in combination with 1.25% potassium hydroxide (KOH) respectively, were investigated. The results revealed that all the three RBIFs have strong glucose adsorption capacity and α-amylase inhibition activity, with 1.25%-SMRBIF being the most effective one. The glucose adsorption capacity increased with increasing porosity and specific surface area of the SMRBIFs, and the maximum glucose bound amount increased by 2–3 folds for acid-alkaline treated RBIFs compared to untreated material. The α-amylase inhibition activity of RBIF was associated with the formation of amylase-RBIF complex as confirmed by fluorescence spectroscopy, with the highest amylase activity inhibitory (24.72%) for 1.25%-SMRBIF. However, the glucose diffusion was retarded a bit stronger by these RBIFs compared to the untreated rice bran, which might be attributed to their larger specific surface area. Therefore, it was suggested that the concentration of postprandial serum glucose lowered by RBIF was mainly ascribed to binding glucose and retarding α-amylase action.

Consumption of essential oils (EOs) and their components, such as eugenol (EU) may reduce chronic disorders, but their use in food is currently limited because of poor solubility and low bioavailability. The aim of this work was to study the influence of carrier oil type, particle size on in vitro lipid digestion and EU release using canola (LCT) and MCT oil-in-water emulsions with different droplet diameters (Coarse > 3000 nm, NE1 > 300 nm and NE2 > 150 nm). There was a progressive increase in the mean particle size of coarse emulsions of both LCT & MCT oils as they passed through simulated gastrointestinal tract consisting of mouth, stomach and intestine phases, which was due to droplet coalescence, flocculation and digestion. However, NE1 and NE2 nanoemulsions showed appreciable increase in particle size after exposure to the simulated intestinal fluid. The rate and extent of in vitro lipid digestion increased with decreasing mean droplet diameter (NE2 ≈ NE1 » Coarse) in both MCT & LCT emulsions. However, MCT emulsions showed faster rate of in vitro lipid digestion which was attributed to more exposure of droplets with the lipase. There was also an appreciable increase in release percentage of eugenol with decreasing droplet diameter (NE2 > NE1 > Coarse) and it was higher in LCT (84%) emulsions which was attributed to large hydrophobic cores that better solubilize EU.

A cellulosic rice bran insoluble dietary fibre (RBIDF) with different structures and physicochemical properties is shown to inhibit the activity of pancreatic lipase (PL) at different levels. The adsorption rate and saturation level to PL were greatest for RBIDF-2.0 (modified with 2.0% H2SO4 + 1.25% KOH), which had the highest specific surface area and oil holding capacity. The conformational deformation of unbound PL in the supernatant of PL-RBIDF confirmed by circular dichroism (CD) suggested that not only bound but also unbound PL activities were altered. Free energy calculations using data from fluorescence spectroscopy revealed that binding of PL to fibre depends primarily on electrostatic interactions, and the binding process is spontaneous and exothermic. This study indicates that dietary intake of cellulosic fractions of rice bran may be useful in reducing the bioavailability of dietary fat by altering the conformation and activity of PL that might be useful to control obesity.

Physicochemical stability and thermal degradation of vitamin E (VE) in nanoemulsions fabricated by low energy emulsification method known as Emulsion Phase Inversion: catastrophic phase inversion (EPI) with different carrier oils (short-chain, medium-chain and long-chain triglycerides) and Tween 80 were investigated. Although nanoemulsions made with VE and the 3 carrier oils showed physical stability to heat shock (30–90 °C, 30 min), ionic strength (0–500 mM), pH (2.0–8.5) and long term storage (60 days, under light and darkness, 4, 25 and 40 °C), there was significant VE degradation in heat processed and long-term storage samples. The VE degradation in long-term storage fitted well with Weibull model, while heat degradation followed the first order kinetics, with medium-chain triglyceride (MCT) based nanoemulsions held at 90 °C showing the greatest degradation rate ( k = 0.1526 × 10 −3 min −1 ) and lowest half-life of 4.54 min. The lack of droplets aggregation or coalescence was associated with absence of electrostatic screening and ion-binding effects. The nanoemulsions stored at 4 °C were more stable than those at 40 °C. The short-chain triglyceride (SCT) based nanoemulsions did not physically withstand the high temperatures (>25 °C) while long-chain triglyceride (LCT) showed good retention in all studied conditions. The VE retention was increased when nanoemulsions were stored in the dark. This study might be helpful to food and pharmaceutical industries in choosing better processing and storage conditions of VE delivery systems.

Microencapsulation is a promising technique to retain the physical attributes of nanoemulsions and to overcome the oxidation of bioactives that become more available to aqueous phase during emulsification. Purity Gum Ultra (PGU) and Hi-CAP 100 (HiCap) emulsified nanoemulsions of Clove Oil (CO) co-encapsulated with Canola oil (CA) and Medium Chain Triglyceride (MCT) (5:5% v/v CO:CA and CO:MCT) were prepared through high pressure homogenization. Microencapsulation of nanoemulsions was performed using Whey Protein Isolates (WPI) under vacuum using freeze drying, which is considered as appropriate method for heat sensitive compounds. The reconstituted emulsions of microencapsulated powder had similar particle sizes as that of fresh nanoemulsions while uncoated showed a big increase (＜400nm). Oxidation of bioactives with and without CO, before and after freeze drying was investigated at different intervals during 60 days of storage at 4 and 25°C by Thiobarbituric Acid Reactive Substances (TBARS) assay. Microencapsulated PGU-CO: CA showed minimum TBARS values compared to other emulsions. Gas chromatography analysis of microcapsules also showed higher retention of CO and lower content on the interphase for aqueous interaction. Conclusively, this study proposes a novel strategy using a freeze drying process to microencapsulate nanoemulsion.

Chitosan–tripolyphosphate nanoparticles have been extensively studied during the last decade because of their numerous applications. In this study, we describe conditions to optimize chitosan nanoparticles as potential nano-fillers in edible films. The ionic cross-linking between the cationic amino groups on the chitosan (CS) chain and the anionic phosphate groups of sodium tripolyphosphate (TPP) was verified via FTIR. Particle size, polydispersity index (PDI) and surface ζ-potential were controlled by chitosan's Mw and concentration, CS:TPP mass ratio, and external conditions such as pH and salinity of the initial chitosan solution. Post-processing methods such as centrifugation and ultra-sonication were used to further control particle size. We show that particle size can be controlled by selecting appropriate conditions. Particles with sizes below 120 nm were produced at different CS:TPP mass ratios depending on the CS concentration. Dilute NaCl was the optimal solution ionic composition that decreased the size by 25% and also resulted in a narrow particle size distribution. We show using UV–vis spectrophotometry that particles of different size, separated by centrifugation had different phosphorus content. Ultra-sonication can be used to reduce the size by 50% but long time caused fragmentation of the nanoparticles. Transmission electron microscopy (TEM) revealed the differences in the morphology of chitosan nanoparticles under various fabrication conditions.

In the present study, polyphenol-rich extracts of wheat bran (PEWB) were prepared via adsorption on macroporous resins and desorption with ethanol. Extraction was performed using aqueous ethanol and four different types of macroporous adsorbent resins for isolation. Specifically, the properties of the macroporous resins were investigated by adsorption and desorption tests. Total polyphenolic content of PEWB was determined using the Folin–Ciocalteu method, and its resistance effects against hydrogen peroxide (H2O2)-induced oxidation on HEK293 cells were assessed by cell viability and the reactive oxygen species (ROS) assay. The results indicate that resin NKA-9 displayed excellent adsorption and separation ability, as well as provided insight into the generation of PEWB from wheat bran extracts. In addition, these results suggest that pretreating HEK293 cells with PEWB prior to H2O2 exposure exhibited a significantly increased survival ratio and reduced the ROS levels. Further investigation involving the phenolic content of PEWB identification and quantification demonstrated that ferulic acid was the most abundant phenolic compound in a number of extracts, which was also confirmed with MTT and ROS assays. Our study revealed that PEWB can prevent HEK293 cells from H2O2-induced oxidative damage.

The structural modifications of insoluble rice bran fiber (IRBF) by sequential regimes of sulphuric acid (H2SO4) and their effects on the physicochemical attributes were studied. The increment of H2SO4 concentration resulted in decreased water holding capacity that ultimately enhanced the oil binding capacity due to the partial removal of starch, protein and hemicelluloses. The starch and hemicelluloses were hydrolyzed exponentially by sequential increments of H2SO4 while protein was mainly dissolved by KOH for all samples. Moreover, higher H2SO4 concentration improved the porosity and crystallinity that led to higher thermal stability of the fiber as evident from XRD and TGA analysis. Furthermore, decreased monosaccharide linkages and increases of porosity with H2SO4 regimes were confirmed by FT-IR and SEM. The change in composition and microstructure of insoluble rice bran fiber (IRBF) induced significant physicochemical changes that might be suitable for their application in the food industry as an anti-diabetic and cholesterol lowering functional ingredient.

The oxidative stability of (-)-epigallocatechin-3-gallate (EGCG) incorporated as inclusion complexes (ICs) in sulfobutylether-β-cyclodextrin sodium (SBE-β-CD) and then ionotropically crosslinked with chitosan hydrochloride (CSH) into nanoparticles were investigated. EGCG-loaded CSH-SBE-β-CD nanoparticles (CSNs) were physically unstable at higher pH and temperature. The particle size of CSNs was unchanged in the pH range of 3-5, but the microenvironment of EGCG-IC appeared to be intact until the pH increased to 6.5 by fluorescence spectroscopy. The physical structure of EGCG-ICs was also affected during storage in addition to CSNs, which was further affected as temperature increased from 25 to 55°C. The decrease in antioxidant activities of EGCG-ICs and free EGCG with increasing pH, storage time and temperature were modest compared to the prominent decreases in antioxidant activities of EGCG-loaded CSNs. The extreme entrapment of EGCG-ICs and/or free EGCG in the aggregated CSNs restricted the release of EGCG, thus inhibiting the antioxidant activities.

Based on encouraged development of potential reduced-exposure products (PREPs) by the US Institute of Medicine, casings (glucose and peptides) added treatments (CAT) and enzymatic (protease and xylanase) hydrolysis treatments (EHT) were developed to study their effect on alkaloids reduction in tobacco and cigarette mainstream smoke (MS) and further investigate the correlation between sensory attributes and alkaloids. Results showed that the developed treatments reduced nicotine by 14.5% and 24.4% in tobacco and cigarette MS, respectively, indicating that both CAT and EHT are potentially effective for developing lower-risk cigarettes. Sensory and electronic nose analysis confirmed the significant influence of treatments on sensory and cigarette MS components. PLSR analysis demonstrated that tobacco alkaloids were positively correlated to the off-taste, irritation and impact attributes, and negatively correlated to the aroma and softness attributes. Additionally, nicotine and anabasine from tobacco leaves positively contributed to the impact attribute, while they negatively contributed to the aroma attribute ( P 0 . 05 ). Meanwhile, most alkaloids in cigarette MS positively contributed to the impact and irritation attributes ( P 0 . 05 ). Hence, this study paved a way to better understand the correlation between tobacco alkaloids and sensory attributes.