Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Database
Language
Publication year range
1.
Food Funct ; 11(1): 768-778, 2020 Jan 29.
Article in English | MEDLINE | ID: mdl-31917381

ABSTRACT

Whey protein isolate (WPI) nanoparticles were fabricated with Ca2+ induced cross-linking and used as an effective particle stabilizer for high internal phase Pickering emulsion (HIPPE) formulation aiming to improve the chemical stability and bioaccessibility of ß-carotene (BC). Ca2+ concentration dominated the characteristics of WPI nanoparticles. Spherically shaped and homogeneously dispersed WPI nanoparticles with a Z-average diameter of approximately 150.0 nm were obtained with 5.0 mM Ca2+ concentration. No cytotoxicity was observed for WPI nanoparticles even at 10.0 mg mL-1 concentration. HIPPE (oil fraction 80.0%, w/w) can be successfully prepared with WPI nanoparticles at a concentration as low as 0.2% (w/w) and was stable for at least 2 months at room temperature. A higher WPI nanoparticle concentration resulted in more solid-like HIPPEs. BC exhibited appreciably higher retention in HIPPEs than in bulk oil during 30 days of storage at 50 °C. Moreover, BC bioaccessibility was appreciably improved with the HIPPE delivery system. Both the chemical stability and bioaccessibility of BC increased with the increase of WPI nanoparticle concentrations from 0.2 to 1.0% (w/w). The results obtained in this study may facilitate the fabrication of edible and biocompatible protein-based nanoparticle stabilizers for HIPPE formulation with more innovative and tailored functionalities.


Subject(s)
Whey Proteins/chemistry , beta Carotene/chemistry , Calcium/chemistry , Digestive System Physiological Phenomena/drug effects , Drug Storage , Emulsions/chemistry , Humans , Nanoparticles , beta Carotene/pharmacokinetics
2.
Food Funct ; 11(2): 1525-1536, 2020 Feb 26.
Article in English | MEDLINE | ID: mdl-31995080

ABSTRACT

Resveratrol (RES)-loaded protein-polysaccharide nanoparticles were fabricated through simple electrostatic interactions with oppositely charged α-lactalbumin (ALA) and chitosan (CHI) with a mass ratio of 5 : 1 without the addition of NaCl at pH 6.5. The Z-average diameter and zeta-potential values of RES-ALA-CHI nanoparticles were 211.0 nm and 13.23 mV, respectively. Both TEM and AFM graphs confirmed that RES-ALA-CHI nanoparticles had a spherical shape, and were dispersed homogeneously at the nanoscale. The encapsulation efficiency (EE) and loading amount (LA) of RES in RES-ALA-CHI nanoparticles were 58.86% and 196.2 µg mg-1, respectively, in the presence of 400 µg mL-1 RES. XRD results confirmed that RES was in amorphous form in ALA-CHI nanoparticles. The interaction between RES and ALA-CHI nanoparticles was mainly driven by hydrophobic interaction and hydrogen bonding. Compared to RES (free), the UV light and heat stability, in vitro bioaccessibility, and antioxidant activity of RES in RES-ALA-CHI nanoparticles were pronouncedly enhanced. The information provided in this study should be of interest to the food industry to fabricate robust nanoscale delivery systems with ALA-CHI nanoparticles for RES and other hydrophobic bioactive compounds.


Subject(s)
Antioxidants , Chitosan/chemistry , Lactalbumin/chemistry , Nanoparticles/chemistry , Resveratrol , Antioxidants/chemistry , Antioxidants/metabolism , Biphenyl Compounds/chemistry , Biphenyl Compounds/metabolism , Drug Carriers/chemistry , Drug Stability , Hydrophobic and Hydrophilic Interactions , Particle Size , Picrates/chemistry , Picrates/metabolism , Resveratrol/chemistry , Resveratrol/metabolism
3.
ACS Sens ; 4(3): 634-644, 2019 03 22.
Article in English | MEDLINE | ID: mdl-30821441

ABSTRACT

Nanopore sensing has emerged as a versatile approach to detection and identification of biomolecules. Presently, researchers rely on experience and intuition for choosing or modifying the nanopores to detect a target analyte. The field would greatly benefit from a computational method that could relate the atomic-scale geometry of the nanopores and analytes to the blockade nanopore currents they produce. Existing computational methods are either computationally too expensive to be used routinely in experimental laboratories or not sensitive enough to account for the atomic structure of the pore and the analytes. Here, we demonstrate a robust and inexpensive computational approach-the steric exclusion model (SEM) of nanopore conductance-that is orders of magnitude more efficient than all-atom MD and yet is sensitive enough to account for the atomic structure of the nanopore and the analyte. The method combines the computational efficiency of a finite element solver with the atomic precision of a nanopore conductance map to yield unprecedented speed and accuracy of ionic current prediction. We validate our SEM approach through comparison with the current blockades computed using the all-atom molecular dynamics method for a range of proteins confined to a solid-state nanopore, biological channels embedded in a lipid bilayer membranes, and blockade currents produced by DNA homopolymers in MspA. We illustrate potential applications of SEM by computing blockade currents produced by nucleosome proteins in a solid-state nanopore, individual amino acids in MspA, and by testing the effect of point mutations on amino acid distinguishability. We expect our SEM approach to become an integral part of future development of the nanopore sensing field.


Subject(s)
DNA/chemistry , Molecular Dynamics Simulation , Nanopores , DNA/metabolism , Electric Conductivity , Ion Transport , Nucleosomes/metabolism , Point Mutation , Porins/genetics , Porins/metabolism , Time Factors
4.
Food Funct ; 9(9): 4781-4790, 2018 Sep 19.
Article in English | MEDLINE | ID: mdl-30124711

ABSTRACT

The health-promoting benefits of resveratrol (RES) have attracted significant attention. Poor water solubility and chemical stability, however, hindered its application. In this study, α-lactalbumin (ALA)-RES nanoparticles were prepared by a simple nanocomplexation protocol. The particle sizes of ALA and the ALA-RES complex were 87.8, and 95.3 nm, respectively. AFM confirmed that both nanoparticles were spherical. XRD results confirmed that RES in ALA nanoparticles was amorphous. Fluorescence spectroscopy and FTIR showed that the ALA-RES nanocomplex was formed mainly by hydrophobic interactions. The water solubility increased by 32 times, compared to that of free RES. ALA nanocomplexation also appreciably improved the chemical stability of RES under all storage conditions, especially at pH 8.0 and high temperature. The ALA-RES nanocomplex showed significantly higher in vitro antioxidant activity than free RES. The results showed that the simple ALA-RES nanocomplex has the potential to be used as an effective antioxidant. The information obtained may enable the expanded application of ALA as an effective nanoscale carrier for delivering RES or other lipophilic nutraceuticals in the functional food, biomedical, and pharmaceutical products.


Subject(s)
Antioxidants/chemistry , Dietary Supplements/analysis , Lactalbumin/chemistry , Nanoparticles/chemistry , Resveratrol/chemistry , Animals , Antioxidants/administration & dosage , Cattle , Food Preservatives/chemistry , Food Storage , Hot Temperature , Hydrogen-Ion Concentration , Hydrophobic and Hydrophilic Interactions , Microscopy, Atomic Force , Particle Size , Protein Stability , Resveratrol/administration & dosage , Solubility , Spectrometry, Fluorescence , Spectroscopy, Fourier Transform Infrared , X-Ray Diffraction
5.
J Agric Food Chem ; 66(36): 9481-9489, 2018 Sep 12.
Article in English | MEDLINE | ID: mdl-30125505

ABSTRACT

The effects of resveratrol (RES)-loaded whey protein isolate (WPI)-dextran nanocomplex on the physicochemical stability of ß-carotene (BC) emulsions were evaluated. WPI-dextran was prepared by Maillard-based glycation and confirmed with gel electrophoresis and OPA assay. WPI-RES and WPI-dextran-RES nanoparticles were prepared with a simple nanocomplexation protocol. Fluorescence spectra indicated that hydrophobic interaction was the main driving force for the WPI-dextran-RES nanocomplex. Spherical and uniformly dispersed structures as well as nanoscale Z-average size (<100 nm) were confirmed for WPI-RES and WPI-dextran-RES nanocomplex with DLS and TEM. The Z-average diameter of emulsions with WPI-dextran conjugate was remarkably lower than that with WPI. Environmental stress (ionic strength, heat, and pH) and storage stability were pronouncedly improved. The chemical stability of BC with WPI-dextran-RES and WPI-RES was also remarkably enhanced when exposed to UV light and thermal treatment. The advantages of the WPI-dextran-RES colloidal complex may provide a better alternative to effectively protect and deliver hydrophobic nutraceuticals.


Subject(s)
Dextrans/chemistry , Stilbenes/chemistry , Whey Proteins/chemistry , beta Carotene/chemistry , Drug Delivery Systems/methods , Drug Stability , Emulsions/chemistry , Hydrophobic and Hydrophilic Interactions , Nanoparticles/chemistry , Osmolar Concentration , Resveratrol , beta Carotene/administration & dosage
6.
Food Chem ; 265: 200-207, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29884373

ABSTRACT

The goal of this study was to improve the chemical stability of menhaden oil and control the lipolysis in emulsions with whey protein during in vitro digestion through EGCG conjugation and genipin-mediated interfacial cross-linking (CL). WPI-EGCG conjugate was successfully synthesized, confirmed by SDS-PAGE, ESI-MS, and phenolic group quantifications (125.3 mg/g), and characterized with far UV CD and ATR-FTIR. Emulsion particle diameter with WPI-EGCG is lower than with WPI. Compared to the native emulsion, WPI CL increased particle diameter and physical stability. Higher oxidative stability was observed for emulsions stabilized with WPI-EGCG conjugate than that with interfacial cross-linking due to the great antioxidant activity. Whereas, WPI CL is more effective than WPI-EGCG conjugate in hindering the rate and extent of lipolysis. The combination of EGCG conjugation and interfacial CL showed both the highest protection of menhaden oil against degradation and highest inhibition on the rate and extent of lipolysis of menhaden oil.


Subject(s)
Emulsions/chemistry , Fish Oils/chemistry , Whey Proteins/chemistry , Antioxidants/chemistry , Catechin/analogs & derivatives , Catechin/chemistry , Circular Dichroism , Digestion , Electrophoresis, Polyacrylamide Gel , Emulsions/metabolism , Iridoids/chemistry , Lipolysis , Oxidation-Reduction , Spectrometry, Mass, Electrospray Ionization , Spectroscopy, Fourier Transform Infrared/methods
7.
Food Chem ; 261: 283-291, 2018 Sep 30.
Article in English | MEDLINE | ID: mdl-29739595

ABSTRACT

In this study, bovine serum albumin (BSA)-caffeic acid (CA) conjugate was prepared with free radical-induced grafting method. The CA to BSA ratio of the conjugate was 115.7 mg/g. In vitro antioxidant activity assays suggested that BSA-CA conjugates had stronger antioxidant activity than BSA. Resveratrol-loaded zein encapsulated with BSA and BSA-CA conjugate core-shell nanoparticles were prepared with antisolvent method. Particle sizes were 206.3 nm, and 217.2 nm for BSA and BSA-CA, respectively. The encapsulation efficiencies (EEs) were 85.3% and 86.5% for zein-BSA and zein-BSA-CA nanoparticles, respectively. SEM results indicated that both nanoparticles were spherical with mean diameter approximately 200 nm and smooth surfaces. Both thermal and UV light stability of resveratrol was significantly improved after nanoencapsulation. BSA-CA conjugate showed remarkably greater protection than BSA against resveratrol degradation. Cellular antioxidant activity (CAA) study confirmed that resveratrol in both zein-BSA and zein-BSA-CA nanoparticles had significant higher antioxidant activities than resveratrol alone.


Subject(s)
Serum Albumin, Bovine/chemistry , Stilbenes/chemistry , Zein/chemistry , Antioxidants/chemistry , Caffeic Acids/chemistry , Drug Stability , Nanoparticles/chemistry , Particle Size , Resveratrol
8.
J Agric Food Chem ; 65(30): 6188-6194, 2017 Aug 02.
Article in English | MEDLINE | ID: mdl-28696684

ABSTRACT

ß-Carotene (BC), a naturally occurring lipophilic carotenoid, is beneficial for human health. However, its water solubility and bioavailability are low. In this study, organogel-based nanoemulsion was successfully prepared to improve the loading amount, solubility, and bioavailability of BC. Corn oil was selected as the oil phase for the organogel as a result of the greatest release amount of BC. Tween 20 was optimized as the emulsifier based on the highest extent of lipolysis and BC bioaccessibility. The nanoemulsion was a better alternative than the organogel according to both the extent of lipolysis and BC bioaccessibility. Cellular uptake of BC was significantly improved through organogel-based nanoemulsion compared to BC suspension. Caveolae-/lipid-raft-mediated route was the main endocytosis pathway. Pharmacokinetic results confirmed that the in vivo bioavailability of BC in nanoemulsion was 11.5-fold higher than that of BC oil. The information obtained suggested that organogel-based nanoemulsion may be an effective encapsulation system for delivery of insoluble and indigestible bioactive compounds.


Subject(s)
Drug Compounding/methods , Nanoparticles/chemistry , beta Carotene/pharmacokinetics , Animals , Biological Availability , Caco-2 Cells , Drug Compounding/instrumentation , Drug Delivery Systems , Emulsifying Agents/chemistry , Emulsions/chemistry , Gels/chemistry , Humans , Male , Polysorbates/chemistry , Rats , Rats, Sprague-Dawley , Solubility , beta Carotene/chemistry
SELECTION OF CITATIONS
SEARCH DETAIL
...