ovalbumin and astaxanthine

The present study aimed to enhance the bioaccessibility of hydrophobic astaxanthin (AST) by developing food-grade emulsion systems. Ovalbumin (OVA) fibrils and candelilla wax-based oleogels were prepared for the next fabrication of AST-loaded oleogel-based Pickering emulsions. The food-grade oleogel was obtained by mixing 0.7% (w/w) candelilla wax and soybean oil. The nano-scale OVA fibrils were observed by transmission electron microscope. SDS-PAGE analysis of OVA fibrils displayed the appearance of peptides with molecular weight around 10 kDa. Contact angle measurement indicated that excellent amphiphilicity endowed OVA fibrils with satisfactory Pickering emulsifier performance. The obtained oleogel-based Pickering emulsions displayed ultrastability during 90-day storage and outstanding freeze-thaw stability. Furthermore, the superiority of AST-loaded oleogel-based Pickering emulsion was further reflected in the apparently ameliorative lipolysis extent and AST bioaccessibility compared with oleogel. This work would facilitate the utilization of OVA and the development of oleogel-based Pickering emulsions with desirable nutraceutical bioaccessibility.

Topics: Emulsions; Organic Chemicals; Ovalbumin; Soybean Oil; Xanthophylls

Although astaxanthin has a variety of biological activities such as anti-oxidant effects, inhibitory effects on skin deterioration and anti-inflammatory effects, its effect on asthma has not been studied. In this paper, the inhibitory effect of astaxanthin on airway inflammation in a mouse model of ovalbumin (OVA)-induced asthma was investigated. We evaluated the number of total cells, Th1/2 mediated inflammatory cytokines in bronchoalveolar lavage fluid (BALF) and airway hyperresponsiveness as well as histological structure. The level of total IgE, IgG1, IgG2a, OVA-specific IgG1, and OVA-specific IgG2a were also examined. The oral administration of 50 mg/mL astaxanthin inhibited the respiratory system resistance, elastance, newtonian resistance, tissue damping, and tissue elastance. Also, astaxanthin suppressed the total cell number, IL-4, and IL-5, and increased the IFN-γ in the BALF. In the sera, total IgE, IgG1, and OVA-specific IgG1 were reduced by astaxanthin exposure and IgG2a and OVA-specific IgG2a were enhanced via oral administration of astaxanthin. Infiltration of inflammatory cells in the lung, production of mucus, lung fibrosis, and expression of caspase-1 or caspase-3 were suppressed in OVA-induced asthmatic animal treated with astaxanthin. These results suggest that astaxanthin may have therapeutic potential for treating asthma via inhibiting Th2-mediated cytokine and enhancing Th1-mediated cytokine.

Topics: Animals; Asthma; Bronchoalveolar Lavage Fluid; Cytokines; Disease Models, Animal; Immunoglobulin E; Mice; Ovalbumin; Protective Agents; T-Lymphocytes, Helper-Inducer; Xanthophylls

L-Ascorbic acid, α-tocopherol, procyanidin B3, β-carotene and astaxanthin are five classic dietary antioxidants. In this study, the interaction between the five antioxidants and ovalbumin was investigated by fluorescence spectroscopy, in combination with UV-vis absorption spectroscopy and circular dichroism (CD) spectroscopy. The quenching mechanism of ovalbumin by α-tocopherol is static quenching and the interaction between α-tocopherol and ovalbumin is synergistically driven by enthalpy and entropy. Electrostatic interactions and hydrophobic interactions play a major role in stabilizing the complex. For the other four antioxidants, the quenching mechanisms are all static quenching mechanisms at lower concentrations of antioxidants, but at higher concentrations of antioxidants, predominantly by the "sphere of action" quenching mechanisms. The binding processes of the other four antioxidants to ovalbumin are all entropy process and the major part of the action force is hydrophobic interactions. The binding constants of ovalbumin with the five antioxidants are in the following order as: astaxanthin > β-carotene > L-ascorbic acid > procyanidin B3 > α-tocopherol at 298 K. Synchronous fluorescence spectroscopy shows the interaction between L-ascorbic acid/β-carotene/astaxanthin and ovalbumin decreases the hydrophobicity of the microenvironment of tryptophan (Trp) and tyrosine (Tyr) residues. The hydrophobicity of Trp is increased while the hydrophility of Tyr is increased in the presence of α-tocopherol. However, the microenvironment of Trp and Tyr is not affected by procyanidin B3. The UV-vis absorption and CD spectra suggest that the interaction between the five antioxidants and ovalbumin leads to the loosening and unfolding of ovalbumin skeleton and exerts some influence on the natural secondary structure of ovalbumin. The study provides an accurate and full basic data for clarifying the binding mechanisms of L-ascorbic acid, α-tocopherol, procyanidin B3, β-carotene and astaxanthin interacting with ovalbumin and is helpful for understanding rational use of antioxidants as dietary supplements.

Topics: alpha-Tocopherol; Animals; Antioxidants; Ascorbic Acid; beta Carotene; Biflavonoids; Binding Sites; Catechin; Circular Dichroism; Humans; Ovalbumin; Proanthocyanidins; Protein Binding; Spectrometry, Fluorescence; Thermodynamics; Xanthophylls

1. Bovine serum albumin (BSA) and/or egg albumin were bound to astaxanthin or canthaxanthin easily and the spectroscopic characteristics of these complexes were similar to those of astaxanthin or canthaxanthin in the salmon muscle. 2. This result indicates that astaxanthin-BSA, -egg albumin, canthaxanthin-BSA and -egg albumin complexes were basically similar to astaxanthin-actomyosin and/or canthaxanthin-actomyosin complex in the salmon muscle. 3. The binding of salmon actomyosin to astaxanthin or canthaxanthin is not specific.

Topics: Actomyosin; Animals; beta Carotene; Canthaxanthin; Carotenoids; Circular Dichroism; Muscles; Ovalbumin; Oxidation-Reduction; Salmon; Serum Albumin, Bovine; Spectrum Analysis, Raman; Xanthophylls