ABSTRACT
Oleofoams are plant oil based whipped systems which have drawn academic and industry attention in recent years. The aim of this study was to determine the effect of fatty acid chain length and monoacylglyceride (MAG) concentration on the performance and structural properties of MAG-based oleofoams. Four different MAGs (monolaurin, monomyrystin, monopalmitin, and monostearin) were studied at three concentration levels (5, 10, and 15 wt%). The fatty acid chain length had a statistically significant impact on the size and shape of crystals formed, while higher MAG concentrations led to higher numbers of crystals in the continuous oil phase. These differences affected the performance and physical properties of the oleofoams: compared to other MAGs, monostearin based oleofoams were harder and exhibited higher values of G' and Gâ³, had higher overrun and showed better stability. Lastly, through microscopy techniques it was successfully proved that monostearin-based oleofoams are stabilized by both bulk and Pickering stabilization.
Subject(s)
Fatty Acids , Organic Chemicals , Organic Chemicals/chemistry , Surface-Active Agents/chemistry , MicroscopyABSTRACT
Fusarium mycotoxin contamination of malting barley has been a persistent food safety issue for malting companies. In this study, the effect of hop essential oil (HEO) nanoemulsion on fungal biomass and mycotoxin production during the malting process was evaluated. Furthermore, the localization of fungal hyphae on the surface and inside the tissue of barley and malts was observed. The application of HEO nanoemulsion reduced fungal biomass and deoxynivalenol (DON) contents at each stage of the malting process as compared to control. During malting process, the fungal hyphae on kernel surfaces was reduced appreciably after steeping. However, the increment of hyphae was observed between the husk and testa layer of barley after germination than raw barley grains. In addition to its antifungal activity, the antioxidant activity of HEO in the treated malts suppressed the formation of aldehydes. This study lays the foundation for the utilization of HEO in the malting industry.
Subject(s)
Fusarium , Hordeum , Mycotoxins , Oils, Volatile , Trichothecenes , Trichothecenes/analysis , Food Contamination/analysis , Hordeum/microbiology , Oils, Volatile/pharmacology , Mycotoxins/analysis , Seedlings/chemistryABSTRACT
Cannabis sativa L. (Cannabis) and its bioactive compounds, including cannabinoids and non-cannabinoids, have been extensively studied for their biological effects in recent decades. Cannabidiol (CBD), a major non-intoxicating cannabinoid in Cannabis, has emerged as a promising intervention for cancer research. The purpose of this review is to provide insights into the relationship between CBD and cancer based on recent research findings. The anticancer effects of CBD are mainly mediated via its interaction with the endocannabinoid system, resulting in the alleviation of pain and the promotion of immune regulation. Published reviews have focused on the applications of CBD in cancer pain management and the possible toxicological effects of its excessive consumption. In this review, we aim to summarize the mechanisms of action underlying the anticancer activities of CBD against several common cancers. Studies on the efficacy and mechanisms of CBD on cancer prevention and intervention in experimental models (i.e., cell culture- and animal-based assays) and human clinical studies are included in this review.
ABSTRACT
Cannabidiol (CBD) is one of the most promising functional food ingredients, which displays a number of health benefits. However, its low solubility and bioavailability impede its applications in functional foods. Herein, we developed a food-grade CBD nanoemulsion system using medium chain triacylglycerides (MCT), canola oil (CO), or hemp seed oil (HSO) as the carrier oil to compare the physicochemical stability and bioaccessibility of CBD. Encouragingly, all formulations were well maintained for 90 days under the tested temperatures (4, 25 and 37 °C) and pH values (3.5 and 7.0). Quantitative analysis of CBD during storage using high performance liquid chromatography revealed that the light exposure and acidity of the solution are two important factors affecting the chemical stability of CBD. Moreover, improved bioaccessibility of CBD in all three nanoemulsion formulations compared to that of bulk oil forms was confirmed, and the long chain triacylglyceride (LCT)-based nanoemulsion was superior to the MCT-based counterpart.
Subject(s)
Cannabidiol , Cannabis , Cannabidiol/chemistry , Cannabis/chemistry , Dietary Supplements , Plant ExtractsABSTRACT
The objective of this study was to investigate the impact of protein type (sodium caseinate and pea protein isolate) and protein to sugar beet pectin mixing ratio (5 : 1 and 2 : 1) on complex coacervate formation, as well as the impact of the finishing technology (freeze-drying and spray-drying) for improving the viability of encapsulated Lactobacillus rhamnosus GG (LGG) in complex coacervates during simulated sequential gastrointestinal (GI) digestion. The physicochemical properties of LGG encapsulated microcapsules in liquid and powder form were evaluated. The state diagram and ζ-potential results indicated that pH 3.0 was the optimum pH for coacervate formation in the current systems. Confocal laser scanning microscopy (CLSM), viscoelastic analysis, and Fourier transform infrared spectroscopy (FTIR) confirmed that the gel-like network structure of the complex coacervates was successfully formed between the protein and SBP at pH 3.0 through electrostatic interaction. In terms of physiochemical properties and viability of LGG encapsulated in the microcapsule powder, the drying method played a crucial role on particle size, microstructure and death rate of encapsulated LGG during simulated sequential GI digestion compared to protein type and biopolymer mixing ratio. For example, the microstructure of spray-dried microcapsules exhibited smaller spherical particles with some cavities, whereas the larger particle size of freeze-dried samples showed a porous sponge network structure with larger particle sizes. As a result, spray-dried LGG microcapsules generally had a lower death rate during simulated sequential gastrointestinal digestion compared to their freeze-dried counterparts. Among all samples, spray-dried PPI-SBP microcapsules demonstrated superior performance against cell loss and maintained more than 7.5 log CFU per g viable cells after digestion.
Subject(s)
Digestion , Pectins/chemistry , Probiotics , Capsules , Drug Compounding , Freeze Drying , Humans , Microbial Viability , Spectroscopy, Fourier Transform Infrared , Spray DryingABSTRACT
In the current study, the chemical composition and total phenolic content of tomato seed flours, along with potential health beneficial properties, including free radical scavenging capacities, anti-inflammatory capacities, and gut microbiota profile modulation, were examined using two different batches. Eight compounds were identified in the tomato seed flour, including malic acid, 2-hydroxyadipic acid, salicylic acid, naringin, N-acetyl-tryptophan, quercetin-di-O-hexoside, kaempferol-di-O-hexoside, and azelaic acid. The total phenolic contents of tomato seed flour were 1.97-2.00 mg gallic acid equivalents/g. Oxygen radical absorbing capacities (ORAC), 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacities (DPPH), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical scavenging capacities (ABTS) were 86.32-88.57, 3.57-3.81, and 3.39-3.58 µmoles Trolox equivalents/g, respectively, on a per flour dry weight basis. The mRNA expression of the pro-inflammatory markers, interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α), were dose-dependently suppressed by tomato seed flour extracts. The extracts altered five of the eight bacterial phyla and genera evaluated. The results may provide some scientific support for the use of tomato seed flour as value-added food ingredients.
Subject(s)
Seeds/chemistry , Solanum lycopersicum/chemistry , Animals , Anti-Inflammatory Agents/analysis , Antioxidants/analysis , Bacteria/drug effects , Chromatography, High Pressure Liquid/methods , Feces/microbiology , Free Radical Scavengers/chemistry , Gastrointestinal Microbiome/drug effects , Male , Mice , Mice, Inbred C57BL , Phenols/chemistry , Plant Extracts/chemistryABSTRACT
In this study, the influence of sunflower wax (SFX) concentration (1, 3, 5, 7, and 9 wt%) on the properties of oleogels prepared using expeller-pressed corn germ oil (EPC) or high oleic soybean oil (EPS) was comprehensively investigated. Overall, oleogels can be prepared from both EP oils at an SFX level ≥3 wt%. The strength of oleogels depends on SFX concentration. EPS oleogels had better rheological properties and a higher amount of platelet-like crystals than EPC oleogels. The characteristics of cookies prepared with both oleogels were evaluated and compared to cookies prepared with commercial shortening. The lipid distribution in the cookies as visualized by CLSM suggested that EPS oleogels with a 5 or 7 wt% SFX had a greater possibility of replacing commercial shortening as they exhibited even lipid distribution which enabled good air-incorporation and air retention abilities. This research provides a foundation for developing healthy bakery products by using minimally processed oil based oleogels.
Subject(s)
Corn Oil/analysis , Organic Chemicals/analysis , Soybean Oil/analysis , Cooking , Fatty Acids , Rheology , Zea maysABSTRACT
The beany flavor of pea protein limits its application in the food industry. This study aimed at addressing this problem by combining the advantages of solid-based spray drying technique and the ability of cyclodextrins (CD) to entrap volatiles. Pea protein isolates (PPI) was extracted by alkaline extraction-isoelectric precipitation, followed by co-spray drying with CD. The resulted PPI-CD showed no major structure changes. HS-SPME-GC-MS coupled to untargeted metabolomics successfully identified 23 aroma compounds that represent the different odorants among PPI-control, physically mixed PPI-CD, and co-spray dried PPI-CD samples. Heat map analysis also showed a remarkable beany odor mitigation effect upon the addition of CD, which was further proved to be due to CD entrapping aroma compounds during spray drying. In the meantime, the functional attributes of PPI-CD were not adversely impacted by the addition of CD.
Subject(s)
Cyclodextrins/chemistry , Odorants/prevention & control , Pea Proteins/chemistry , Pisum sativum/chemistry , Spray Drying , Corn Oil/chemistry , Emulsions , Flavoring Agents/chemistry , Food Handling/methods , Hot Temperature , Hydrogen-Ion Concentration , Powders/chemistry , Solubility , Taste , Water/chemistryABSTRACT
The objective of this research was to fabricate crude soybean oil oleogels (CSO) using ß-sitosterol (BS) and/or monoacylglycerol (MAG) and compare their role with that of refined soybean oil oleogels (RSO) in cookie making. Both crude and refined soybean oil oleogels were formed with BS or MAG, or the combination of both (1 : 1) at a fixed concentration of 10 wt%. The thermal behavior of the oleogels was measured using differential scanning calorimetry (DSC). The crystal structure and morphology of the oleogels were characterized using X-ray diffraction (XRD) and polarized light microscopy (PLM). The hardness of the oleogel and commercial vegetable shortening was compared using a texture analyzer. The characteristics of cookies made with the oleogels were compared with those of cookies made with commercial vegetable shortening. Overall, the incorporation of BS and/or MAG into crude and refined soybean oil can produce oleogels with solid-like properties. Refined soybean oil formed stronger and firmer oleogels as compared to crude soybean oil. RSO structured by BS presented branched fiber-like, elongated plate-like, and needle-like crystals while the same oil gelled by MAG contained spherulite crystals. RSO made with the combination of BS and MAG displayed crystal morphologies from both BS and MAG. The same crystal morphologies were observed in CSO with lower quantities. Comparing the quality of cookies made with the oleogels and commercial vegetable shortening, equal or better performance of both RSO and CSO in terms of weight, thickness, width, spread ratio, and hardness of cookies than that of commercial vegetable shortening was observed. By combining the results of the physical characterization and cookie making performance, it can be concluded that both crude and refined soybean oleogels could resemble commercial shortening, which offers the possibility of using oleogels to replace shortening in the baking industry.
Subject(s)
Cooking , Monoglycerides/chemistry , Sitosterols/chemistry , Soybean Oil/chemistry , Organic Chemicals/chemistryABSTRACT
Fusarium mycotoxin contamination in malting barley is of great concerns in malting industry. Our recent study found that clove oil nanoemulsions can act as highly efficient antifungal agents in vitro. Therefore, we explored the efficacy of clove oil nanoemulsions on Fusarium growth and mycotoxin during malting process. The impact of emulsifier types (Tween 80, BSA and quillaja saponins) on the formation of clove oil nanoemulsion, the mitigation effects on mycotoxin levels and fungal biomass, and the clove oil flavor residues on malts were measured. We observed that 1.5 mg clove oil/g nanoemulsion showed a negligible influence on germinative energy of barley, while still efficiently eliminated the DON levels and toxicogenic fungal biomass as quantified by Tri5 DNA content. Tween 80-stablized clove oil nanoemulsion displayed higher mycotoxin inhibitory activity and less flavor impact on the final malt. The results indicated the potential application of essential oil nanoemulsion during the malting process.
Subject(s)
Fusarium/drug effects , Hordeum/microbiology , Mycotoxins/biosynthesis , Trichothecenes/metabolism , Clove Oil/pharmacology , Fusarium/metabolism , Germination/drug effects , Hordeum/chemistry , Water/pharmacologyABSTRACT
This study aimed to develop a headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) method for the quantification of 3-monochloropropane-1,2-diol fatty acid esters (3-MCPDEs) and 2-monochloropropane-1,3-diol fatty acid esters (2-MCPDEs), and semi-quantification of glycidyl fatty acid esters (GEs) in edible oils. A central composite design was implemented to optimize the derivatization temperature and extraction time, which were 100⯰C and 80â¯min, respectively. HS-SPME coupled with in-situ derivatization was more straightforward (three steps) and sensitive, with a limit of detection of 16% (3.9⯵g/L) and 11% (5.3⯵g/L) higher than that of liquid injection method, for 3-MCPD and 2-MCPD, respectively. The recoveries of 3-MCPD and 2-MCPD were in the range of 91.1% to 102.1%, with a relative standard deviation ranging from 0.08 to 9.29%. The validated methodology was successfully applied to oil samples. Further efforts will focus on shortening the extraction time, as 80â¯min is relatively long.
Subject(s)
Esters/analysis , Gas Chromatography-Mass Spectrometry , Glycerol/analogs & derivatives , Plant Oils/chemistry , Solid Phase Microextraction/methods , alpha-Chlorohydrin/chemistry , Esters/chemistry , Fatty Acids/chemistry , Food Contamination/analysis , Glycerol/chemistry , Limit of DetectionABSTRACT
This study aimed to develop an alternative method named state diagram to identify boundary formation pH for complex coacervates between pea protein isolate (PPI) and sugar beet pectin (SBP) at concentrated solutions (~2.0â¯wt%). The effects of pH (7-2) and PPI-SBP mixing ratios (1:1-20:1) on coacervates formation were investigated by state diagram, zeta-potential, rheological, and phase composition analysis. Isothermal titration calorimetry, scanning electron microscopy, and Fourier transform infrared spectroscopy were employed to elucidate thermodynamic behaviors, non-covalent bonding of coacervates, and microstructure of coacervates. We demonstrate that state diagram can explicitly identify the three characteristic pH values (pHφ1, pHopt, and pHφ2) at which recognizable transitions take place in concentrated colloids solutions. The mixing ratio dependent of pHφ1 increased to pH 5.5 as PPI-SBP mixing ratio increased to 20:1. The pHopt was recognized at the net charge neutrality or the highest storage modulus of the mixed colloids solutions.
Subject(s)
Pea Proteins/chemistry , Pectins/chemistry , Thermodynamics , Beta vulgaris/chemistry , Calorimetry , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Spectroscopy, Fourier Transform InfraredABSTRACT
The expeller-pressed (EP) corn germ oil oleogels were prepared using rice bran wax (RBX) at different concentrations (3, 5, 7, and 9â¯wt%). Their structural properties, including color, hardness, thermal behavior, rheological property, and crystal structure were evaluated. The performance of oleogels for potential food application was examined by incorporating oleogels into cookies as a fully replacement for commercial shortenings. Overall, RBX could form oleogels in both refined and EP corn germ oils at a concentration ≥3â¯wt%. Refined corn oil produced a stronger gel than crude corn oil. When comparing cookie characteristics, cookies made with both types of oleogels showed similar properties with commercial cookies. This result indicates that oleogels made by refined and EP corn germ oil together with RBX have the potential to imitate the functionality of commercial shortening in the baking industry.
Subject(s)
Corn Oil/chemistry , Oryza/chemistry , Zea mays/metabolism , Color , Food Handling , Hardness , Organic Chemicals/chemistry , Oryza/metabolism , Plant Oils/chemistry , Rheology , Waxes/chemistryABSTRACT
This research aims to study antioxidative activities of polar solvent extractable phenolic compounds from yellow peas with different germination times against oil-in-water emulsion oxidation. After germination (0, 2, 4, and 6 days), soluble free and polar soluble bound phenolic compounds were extracted and their antioxidative activity was evaluated using stripped soybean oil (SSO)-in-water emulsions. Liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection (SEC-MALS-RI) were employed to analyze the phenolic composition and molar mass, respectively. Antioxidative activities of soluble free phenolic compounds increased in the SSO-in-water emulsion system, while those of polar soluble bound phenolic compounds decreased with germination. On the basis of chemometric analysis, pratensein (2), phloridzin (4), quercetin (9), sayanedine (12), hesperetin (13), glyzaglabrin (14), and pinocembrin (15) were speculated as the pivotal phenolic compounds responsible for the hydrogen donating capacity. Additionally, decreased molecular weight of soluble bound phenolic compounds was accompanied by the reduction of antioxidative activity in SSO-in-water emulsions indicating that the moieties of polar soluble bound phenolic compounds also have an important impact on the antioxidative activity of phenolic compounds.
Subject(s)
Germination , Oxidation-Reduction , Phenols/chemistry , Pisum sativum/chemistry , Antioxidants , Chromatography, Gel , Chromatography, Liquid , Emulsions , Pisum sativum/metabolism , Plant Extracts/chemistry , Soybean Oil , Spectrometry, Mass, Electrospray Ionization , Time FactorsABSTRACT
The influence of ionic surfactants (cationic surfactant lauric arginate and anionic surfactant lysolecithin) on the physical properties, antifungal and mycotoxin inhibitory efficacy of Tween 80 stabilized cinnamon oil-in-water nanoemulsions was investigated. Nanoemulsion droplets of similar particle diameter (â¼100 nm), but variable electrical characteristics, were formed by mixing 0.1 wt% ionic surfactant with 0.9 wt% Tween 80 before homogenization. The nanoemulsions were physically stable over 28 days at 23 °C. The antifungal activity (against mycelial growth and spore germination) and mycotoxin inhibitory activity of cinnamon oil nanoemulsions bearing positive, neutral, and negative charge surface was then evaluated against two chemotypes of Fusarium graminearum. In general, the cinnamon oil played a decisive role in the resulting antifungal and mycotoxin inhibitory activities. The surfactant charge had a limited impact on the antifungal mycotoxin inhibitory activities of cinnamon oil in the nanoemulsions. Both ionic surfactant-based cinnamon oil nanoemulsions showed greater activity in inhibiting mycelial growth and mycotoxin production of F. graminearum than those based on Tween 80. Treatment of mycelium with cinnamon oil nanoemulsions resulted in the loss of cytoplasm from fungal hyphae, and accounted for the antifungal action. These results have important implications for the design of essential oil based nanoemulsions as effective antifungal delivery systems in foods.
Subject(s)
Antifungal Agents/pharmacology , Cinnamomum zeylanicum/chemistry , Mycotoxins/antagonists & inhibitors , Plant Oils/pharmacology , Surface-Active Agents/pharmacology , Antifungal Agents/chemistry , Emulsions/chemistry , Emulsions/pharmacology , Fusarium/drug effects , Fusarium/growth & development , Fusarium/metabolism , Mycotoxins/metabolism , Plant Oils/chemistry , Surface-Active Agents/chemistryABSTRACT
In this study, base algae oil was gelled through the formation of a crystal network using food-grade monoacylglycerol (MAG). The impact of the MAG concentration (5, 10, 20 wt%) and water content (0, 5 wt%) on the physical properties and oxidative stability of the gelled algae oil was systematically investigated. The antioxidative activity of 300 µM hydrophilic antioxidant, i.e., ascorbic acid and green tea extract, on the oxidative stability of the gelled algae oil by 20 wt% of MAG was also examined. The results obtained clearly showed that the melting temperature, melting of entropy, and complex modulus of the algae oil increased with increasing the MAG concentration. The addition of 5 wt% water could negatively affect the strength of the MAG crystal network, while a physically stable gel system could only be formed with 20 wt% MAG. The stronger crystal network formed by 20 wt% MAG retarded the lipid oxidation of algae oil due to the creation of a physical barrier to restrain the attack from oxygen. The addition of green tea extract could further synergize with the MAG crystalline network by forming a thermodynamic barrier to effectively quench the radicals, thus prolonging the oxidative stability of algae oil 4-fold longer than that of the base algae oil.
Subject(s)
Antioxidants/chemistry , Monoglycerides/chemistry , Plant Oils/chemistry , Hydrophobic and Hydrophilic Interactions , Oxidation-ReductionABSTRACT
Our recent study found that antioxidative activity of phenolic compounds extracted from germinated chickpea was boosted in both in vitro assays and oil-in-water emulsions [ Xu et al. Food Chem. 2018 , 250 , 140 ]. The purpose of this study was to elucidate the mechanism by which germination enhances the antioxidative activity of the phenolic compounds extracted from chickpea. Liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection (SEC-MALS-RI) were employed to evaluate the phenolic composition of soluble phenolic compounds (free and bound) and molar masses of soluble bound phenolic compounds, respectively, over 6 days of germination. According to principal-component analysis of the interrelationship between germination time and phenolic composition, it is revealed that protocatechuic acid 4- O-glucoside and 6-hydroxydaidzein played a pivotal role in the soluble free phenolic compounds, whereas gentisic acid and 7,3',4'-trihydroxyflavone were important in the soluble bound phenolic compounds. Molar masses of soluble bound phenolic compounds were increased after 6 days of germination. Protective and dual antioxidative effects were proposed to explicate how the antioxidative activity of soluble bound phenolic compounds in oil-in-water emulsions was improved with germination.
Subject(s)
Antioxidants/chemistry , Cicer/chemistry , Cicer/growth & development , Plant Extracts/chemistry , Antioxidants/isolation & purification , Chromatography, High Pressure Liquid , Flavonoids/chemistry , Flavonoids/isolation & purification , Germination , Plant Extracts/isolation & purification , Seeds/chemistry , Seeds/growth & development , Spectrometry, Mass, Electrospray IonizationABSTRACT
The influence of oil composition on the physical properties and antifungal and mycotoxin inhibitory activity of clove oil-in-water nanoemulsions was investigated. Physically stable clove oil-in-water nanoemulsions could be fabricated by incorporating either ≥75 wt% of corn oil or ≥50 wt% of medium chain triacylglycerol (MCT) into clove oil before homogenization to prevent Ostwald ripening. The clove oil-in-water nanoemulsions with mean diameters of <150 nm showed high physical stability over 30 days storage. The antifungal activity of physically stable clove oil nanoemulsions was further evaluated using effective concentration (EC) and inhibitory activity towards mycotoxin production in two chemotypes of Fusarium graminearum isolates. The composition of the oil phase, i.e., ripening inhibitor type and concentration, in clove oil-in-water nanoemulsions had a remarkable impact on antifungal activity as well as inhibition of mycotoxin production. In general, under the same clove oil concentration in oil phase, the addition of MCT decreased the antifungal and mycotoxin inhibitory activity of clove oil more than corn oil. Compared with the bulk clove oil, this study also indicated that the mycotoxin inhibitory activity of clove was significantly enhanced when encapsulated in nanoemulsions. These results have important implications for the design of essential oil based nanoemulsions as effective antifungal and detoxification delivery systems in the food or other industries.
Subject(s)
Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Clove Oil/chemistry , Clove Oil/pharmacology , Mycotoxins/biosynthesis , Oils, Volatile/chemistry , Emulsions/chemistry , Emulsions/pharmacology , Fusarium/drug effects , Fusarium/metabolism , Oils, Volatile/pharmacology , Particle Size , Syzygium/chemistryABSTRACT
A highly sensitive electrochemical biosensor based on the synthetized L-Cysteine-Ag(I) coordination polymer (L-Cys-Ag(I) CP), which looks like a protein-mimicking nanowire, was constructed to detect acetylcholinesterase (AChE) activity and screen its inhibitors. This sensing strategy involves the reaction of acetylcholine chloride (ACh) with acetylcholinesterase (AChE) to form choline that is in turn catalytically oxidized by choline oxidase (ChOx) to produce hydrogen peroxide (H2O2), thus L-Cys-Ag(I) CP possesses the electro-catalytic property to H2O2 reduction. Herein, the protein-mimicking nanowire-based platform was capable of investigating successive of H2O2 effectively by amperometric i-t (current-time) response, and was further applied for the turn-on electrochemical detection of AChE activity. The proposed sensor is highly sensitive (limit of detection is 0.0006 U/L) and is feasible for screening inhibitors of AChE. The model for AChE inhibition was further established and two traditional AChE inhibitors (donepezil and tacrine) were employed to verify the feasibility of the system. The IC50 of donepezil and tacrine were estimated to be 1.4â¯nM and 3.5â¯nM, respectively. The developed protocol provides a new and promising platform for probing AChE activity and screening its inhibitors with low cost, high sensitivity and selectivity.
Subject(s)
Acetylcholinesterase/metabolism , Biosensing Techniques , Cholinesterase Inhibitors/pharmacology , Drug Evaluation, Preclinical/instrumentation , Drug Evaluation, Preclinical/methods , Electrochemical Techniques , Nanowires/chemistry , Acetylcholine/chemistry , Acetylcholine/metabolism , Biocatalysis , Choline/biosynthesis , Choline/chemistry , Cholinesterase Inhibitors/chemistry , Cysteine/chemistry , Cysteine/pharmacology , Electrodes , Polymers/chemistry , Polymers/pharmacology , Silver/chemistry , Silver/pharmacologyABSTRACT
BACKGROUND: Carotenoids, such as ß-carotene, are widely used in foods and beverages as natural colorants and nutraceuticals. We investigated the influence of carrier oil composition (ratio of digestible to indigestible oil) on the physical stability, microstructure and bioaccessibility of ß-carotene nanoemulsions using a simulated gastrointestinal tract model. RESULTS: ß-Carotene nanoemulsions (d < 150 nm) were formed by high-pressure homogenization using sucrose monoester and lysolecithin as emulsifiers, and mixtures of corn oil (digestible) and lemon oil (indigestible) as the lipid phase. All of the nanoemulsions underwent extensive droplet aggregation under mouth, stomach and small intestine conditions. The extent of free fatty acid production in the small intestine increased as the amount of digestible oil in the droplets increased. The bioaccessibility of ß-carotene also increased with increasing digestible oil content, ranging from â¼5% for the pure lemon oil system to â¼76% for the pure corn oil system. This effect was attributed to the ability of mixed micelles formed from triglyceride digestion products (free fatty acids and monoglycerides) to solubilize ß-carotene. CONCLUSIONS: This study provides important information for developing effective delivery systems for lipophilic bioactive components in food and beverage applications.