Physico-chemical stability of astaxanthin nanodispersions prepared with polysaccharides as stabilizing agents

Improved bioavailability and antioxidation of β-carotene-loaded biopolymeric nanoparticles stabilized by glycosylated oat protein isolate

The limited bioavailability of β-carotene hinders its potential application in functional foods, despite its excellent antioxidant properties. Protein-based nanoparticles have been widely used for the delivery of β-carotene to overcome this limitation. However, these nanoparticles are susceptible to environmental stress. In this study, we utilized glycosylated oat protein isolate to prepare nanoparticles loaded with β-carotene through the emulsification-evaporation method, aiming to address this challenge. The results showed that β-carotene was embedded into the spherical nanoparticles, exhibiting relatively high encapsulation efficiency (86.21 %) and loading capacity (5.43 %). The stability of the nanoparticles loaded with β-carotene was enhanced in acidic environments and under high ionic strength. The nanoparticles offered protection to β-carotene against gastric digestion and facilitated its controlled release (95.76 % within 6 h) in the small intestine, thereby leading to an improved in vitro bioavailability (65.06 %) of β-carotene. This improvement conferred the benefits on β-carotene nanoparticles to alleviate tert-butyl hydroperoxide-induced oxidative stress through the upregulation of heme oxygenase-1 and NAD(P)H quinone dehydrogenase 1 expression, as well as the promotion of nuclear translocation of nuclear factor-erythroid 2-related factor 2. Our study suggests the potential for the industry application of nanoparticles based on glycosylated proteins to effectively deliver hydrophobic nutrients and enhance their application.

Preparation of Porous Scaffold Based on Poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) and FucoPol

This work focused on the development of porous scaffolds based on biocomposites comprising two biodegradable and biocompatible biopolymers: a terpolyester, poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) (PHBHVHHx), and the bacterial polysaccharide FucoPol. The PHBHVHHx terpolymer was composed of 3-hydroxybutyrate (55 wt%), 3-hydroxyvalerate (21 wt%), and 3-hydroxyhexanoate (24 wt%). This hydrophobic polyester has low crystallinity and can form elastic and flexible films. Fucopol is a fucose-containing water-soluble polysaccharide that forms viscous solutions with shear thinning behavior and has demonstrated emulsion-forming and stabilizing capacity and wound healing ability. Emulsion-templating was used to fabricate PHA-based porous structures in which FucoPol acted as a bioemulsifier. Compared with the scaffolds obtained from emulsions with only water, the use of FucoPol aqueous solutions resulted in structures with improved mechanical properties, namely higher tensile strength (4.4 MPa) and a higher Young's Modulus (85 MPa), together with an elongation at break of 52%. These features, together with the scaffolds' high porosity and pore interconnectivity, suggest their potential to sustain cell adhesion and proliferation, which is further supported by FucoPol's demonstrated wound healing ability. Therefore, the developed PHBHVHHx:FucoPol scaffolds arise as innovative porous bioactive structures with great potential for use in tissue engineering applications.

Production and therapeutic use of astaxanthin in the nanotechnology era

Astaxanthin (AXT) is a red fat-soluble pigment found naturally in aquatic animals, plants, and various microorganisms and can be manufactured artificially using chemical catalysis. AXT is a xanthophyll carotenoid with a high potential for scavenging free radicals. Several studies have investigated AXT efficacy against diseases such as neurodegenerative, ocular, skin, and cardiovascular hypertension, diabetes, gastrointestinal and liver diseases, and immuno-protective functions. However, its poor solubility, low stability to light and oxygen, and limited bioavailability are major obstacles hindering its wide applications as a therapeutic agent or nutritional supplement. Incorporating AXT with nanocarriers holds great promise in enhancing its physiochemical properties. Nanocarriers are delivery systems with several benefits, including surface modification, bioactivity, and targeted medication delivery and release. Many approaches have been applied to enhance AXT's medicinal effect, including solid lipid nanoparticles, nanostructured lipid carriers (NLCs) and polymeric nanospheres. AXT nano-formulations have demonstrated a high antioxidant and anti-inflammatory effect, significantly affecting cancer in different organs. This review summarizes the most recent data on AXT production, characterization, biological activity, and therapeutic usage, focusing on its uses in the nanotechnology era.

Research progress of Astaxanthin nano-based drug delivery system: Applications, prospects and challenges?

Astaxanthin (ASX) is a kind of carotenoid widely distributed in nature, which has been shown to extremely strong antioxidative effects and significant preventive and therapeutic effects on cancer, diabetes, cardiovascular disease, etc. However, its application in the medical field is greatly limited due to its poor water solubility, unstable chemical properties and other shortcomings. In recent years, the nano-based drug delivery systems such as nanoparticles, liposomes, nanoemulsions, nanodispersions, and polymer micelles, have been used as Astaxanthin delivery carriers with great potential for clinical applications, which have been proved that they can enhance the stability and efficacy of Astaxanthin and achieve targeted delivery of Astaxanthin. Herein, based on the pharmacological effects of Astaxanthin, we reviewed the characteristics of various drug delivery carriers, which is of great significance for improving the bioavailability of Astaxanthin.

Improving the biological activities of astaxanthin using targeted delivery systems

The antioxidant and anti-inflammatory properties of astaxanthin (AST) enable it to protect against oxidative stress-related and inflammatory diseases with a range of biological effects. These activities provide the potential to develop healthier food products. Therefore, it would be beneficial to design delivery systems for AST to overcome its low stability, control its release, and/or improve its bioavailability. This review discusses the basis for AST's various biological activities and the factors limiting these activities, including stability, solubility, and bioavailability. It also discusses the different systems available for the targeted delivery of AST and their applications in enhancing the biological activity of AST. These include systems that are candidates for preventive and therapeutic effects, which include nerves, liver, and skin, particularly for possible cancer reduction. Targeted delivery of AST to specific regions of the gastrointestinal tract, or more selectively to target tissues and cells, can be achieved using targeted delivery systems to increase the biological activities of AST.

Eugenol nanoemulsion inactivates Listeria monocytogenes, Salmonella Enteritidis, and Escherichia coli O157:H7 on cantaloupes without affecting rind color

Listeria monocytogenes, Salmonella Enteritidis, and Escherichia coli O157:H7 are the major foodborne pathogens that have been implicated in outbreaks related to consumption of contaminated cantaloupes. Current chlorine-based decontamination strategies are not completely effective for inactivating the aforementioned pathogens on cantaloupes, especially in the presence of organic matter. This study investigated the efficacy of eugenol nanoemulsion (EGNE) wash treatments in inactivating L. monocytogenes, Salmonella spp., and E. coli O157:H7 on the surface of cantaloupes. In addition, the efficacy of EGNE in inhibiting the growth of the three pathogens on cantaloupes during refrigerated and room temperature storage of 5 days was investigated. Moreover, the effect of EGNE wash treatment on cantaloupe color was assessed using a Miniscan® XE Plus. The EGNE was prepared with either Tween 80 (TW) or a combination of Gum arabic and Lecithin (GA) as emulsifiers. The cantaloupe rind was washed with EGNE (0.3, 0.6, and 1.25%), in presence or absence of 5% organic load, for 1, 5, or 10 min at 25°C. Enumeration of surviving pathogens on cantaloupe was performed by serial dilution and plating on Oxford, XLD or SMA agar followed by incubation at 37°C for 24–48 h. EGNE-GA and EGNE-TW wash significantly reduced all three pathogens by at least 3.5 log CFU/cm2 as early as 5 min after treatment. EGNE-GA at 1.25% inactivated L. monocytogenes, E. coli O157:H7 and S. Enteritidis on cantaloupes to below the detectable limit within 5 and 10 min of treatment, respectively (~4 log CFU/cm2, P < 0.05). EGNE treatments significantly reduced the survival of L. monocytogenes, S. Enteritidis, and E. coli O157:H7 on cantaloupe by at least 6 log CFU/cm2 at day 5 of storage at 25 and 4°C (P < 0.05). Presence of organic matter did not modulate the antimicrobial efficacy of nanoemulsion treatments (P > 0.05). EGNE treatments did not affect the rind color of cantaloupes (P > 0.05). In conclusion, eugenol nanoemulsions could potentially be used as a natural sanitizer to inactivate foodborne pathogens on cantaloupes. Further investigations in an industry setting are warranted.

Recent research advances in astaxanthin delivery systems: Fabrication technologies, comparisons and applications

Astaxanthin (AST) is classified as a kind of carotenoid with bright red color, powerful antioxidant activity as well as a range of health benefits. AST-based functional foods present a new thought of healthy diets with both the enhancement of food color and incorporation of nutrients. However, the poor water solubility, easy oxidation, light instability, thermal instability and peculiar smell excessively restrict its application in the food industry. In this review, common bio-based materials for various AST delivery systems suitable for different food products are highlighted. Moreover, characteristics of different delivery systems and current applications in food products are also compared and summarized. This review provides some ideas on the research trends and applications of AST delivery systems in food. The joint use of two or more materials can significantly enhance the stability of delivery systems. All of the encapsulation systems slow down the degradation of AST to a certain extent and can be applied to different food systems. However, studies and applications are still focused on emulsions and microcapsules with unsatisfactory odor masking effects. In the future, diverse AST-loaded delivery systems with high encapsulation efficacy, good stability, odor masking effects and cost-effective preparation technologies will be the major research trends.

An integration study of microalgae bioactive retention: From microalgae biomass to microalgae bioactives nanoparticle

Microalgae metabolites include biologically active compounds with therapeutic effects such as anticancer, anti-inflammatory and immunomodulation effects. One of the most recent focuses is on utilizing microalgae lipid-based biologically active compounds in food applications. However, most microalgae biological active compounds in their natural forms have common drawbacks like low solubility, low physicochemical stability and strong susceptibility to degradation, which significantly limits their application in foods, therefore, it is important to find solutions to retain their functional properties. In the present work, a comprehensive review on multi-product biorefinery was carried out from upstream processing stage to downstream processing stage, and identify critical processes and factors that impact bioactive material acquisition and retention. Furthermore, since nanoencapsulation technology emerges as an effective solution for microalgae nutraceutical product's retention, this work also focus on the nanoparticle perspective and comprehensively reviews the current nanoencapsulation solutions of the microalgae bioactive extract products. The aim is to depict advances in the formulations of microalage bioactive nanoparticles and provide a critical analysis of the reported nanoparticle formation. Overall, through the investigation of microalgae from biomass to bioactive nanoparticles, we aim to facilitate microalgae nutraceuticals incorporation as high value-added ingredients in more functional food that can improve human health.

Microalgae Encapsulation Systems for Food, Pharmaceutical and Cosmetics Applications

Microalgae are microorganisms with a singular biochemical composition, including several biologically active compounds with proven pharmacological activities, such as anticancer, antioxidant and anti-inflammatory activities, among others. These properties make microalgae an interesting natural resource to be used as a functional ingredient, as well as in the prevention and treatment of diseases, or cosmetic formulations. Nevertheless, natural bioactives often possess inherent chemical instability and/or poor solubility, which are usually associated with low bioavailability. As such, their industrial potential as a health-promoting substance might be severely compromised. In this context, encapsulation systems are considered as a promising and emerging strategy to overcome these shortcomings due to the presence of a surrounding protective layer. Diverse systems have already been reported in the literature for natural bioactives, where some of them have been successfully applied to microalgae compounds. Therefore, this review focuses on exploring encapsulation systems for microalgae biomass, their extracts, or purified bioactives for food, pharmaceutical, and cosmetic purposes. Moreover, this work also covers the most common encapsulation techniques and types of coating materials used, along with the main findings regarding the beneficial effects of these systems.

Astaxanthin-loaded polymer-lipid hybrid nanoparticles (ATX-LPN): assessment of potential otoprotective effects

Background

Ototoxicity is one of the major side effects of platinum-based chemotherapy, especially cisplatin therapy. To date, no FDA approved agents to alleviate or prevent this ototoxicity are available. However, ototoxicity is generally believed to be produced by excessive generation of reactive oxygen species (ROS) in the inner ear, thus leading to the development of various antioxidants, which act as otoprotective agents. Astaxanthin (ATX) is an interesting candidate in the development of new therapies for preventing and treating oxidative stress-related pathologies, owing to its unique antioxidant capacity.

Methods and results

In this study, we aimed to evaluate the potential antioxidant properties of ATX in the inner ear by using the HEI-OC1 cell line, zebrafish, and guinea pigs. Because ATX has poor solubility and cannot pass through round window membranes (RWM), we established lipid-polymer hybrid nanoparticles (LPN) for loading ATX. The LPN enabled ATX to penetrate RWM and maintain concentrations in the perilymph in the inner ear for 24 h after a single injection. ATX-LPN were found to have favorable biocompatibility and to strongly affect cisplatin-induced generation of ROS, on the basis of DCFHDA staining in HEI-OC1 cells. JC-1 and MitoTracker Green staining suggested that ATX-LPN successfully reversed the decrease in mitochondrial membrane potential induced by cisplatin in vitro and rescued cells from early stages of apoptosis, as demonstrated by FACS stained with Annexin V-FITC/PI. Moreover, ATX-LPN successfully attenuated OHC losses in cultured organ of Corti and animal models (zebrafish and guinea pigs) in vivo. In investigating the protective mechanism of ATX-LPN, we found that ATX-LPN decreased the expression of pro-apoptotic proteins (caspase 3/9 and cytochrome-c) and increased expression of the anti-apoptotic protein Bcl-2. In addition, the activation of JNK induced by CDDP was up-regulated and then decreased after the administration of ATX-LPN, while P38 stayed unchanged.

Conclusions

To best of our knowledge, this is first study concluded that ATX-LPN as a new therapeutic agent for the prevention of cisplatin-induced ototoxicity.

Receptor-Mediated Delivery of Astaxanthin-Loaded Nanoparticles to Neurons: An Enhanced Potential for Subarachnoid Hemorrhage Treatment

Astaxanthin (ATX) is a carotenoid that exerts strong anti-oxidant and anti-inflammatory property deriving from its highly unsaturated molecular structures. However, the low stability and solubility of ATX results in poor bioavailability, which markedly hampers its application as therapeutic agent in clinic advancement. This study investigated a promising way of transferrin conjugated to poly (ethylene glycol) (PEG)-encapsulated ATX nanoparticles (ATX-NPs) on targeted delivery and evaluated the possible mechanism underlying neuroprotection capability. As a result, the ATX integrated into nanocarrier presented both well water-dispersible and biocompatible, primely conquering its limitations. More than that, the transferrin-containing ATX-NPs exhibited enhanced cellular uptake efficiency than that of ATX-NPs without transferrin conjugated in primary cortical neurons. Additionally, compared to free ATX, transferrin-containing ATX-NPs with lower ATX concentration showed powerful neuroprotective effects on OxyHb-induced neuronal damage. Taken together, the improved bioavailability and enhanced neuroprotective effects enabled ATX-NPs as favorable candidates for targeted delivery and absorption of ATX. We believe that these in vitro findings will provide insights for advancement of subarachnoid hemorrhage therapy.

Preparation of maltodextrin stabilized α-tocopherol nanoemulsions using solvent-displacement technique

α-Tocopherol nanoemulsions were prepared in current research using various proportions of Polysorbate 20 and maltodextrin as binary stabilizer mixtures through solvent-displacement technique. The effects of maltodextrin proportion in stabilizer mixture, on physicochemical characteristics of gained nanoemulsions, namely average particle size, polydispersity index (PDI), zeta potential, conductivity, in vitro antioxidant activity, in vitro cellular uptake and their rheological parameters were studied. The results show that using maltodextrin, as surface active biopolymer, together with Polysorbate 20, as small molecular stabilizer, could improve the characteristics of nanoemulsions considerably. The studied characteristics of all prepared shear-thinning (pseudo-plastic) nanoemulsions were well fitted to maltodextrin proportions via various polynomial models using regression statistical analysis. Thus, applying the surface active polysaccharides as stabilizer, in nanoemulsion formulations, and tuning its proportions to general used small molecular emulsifiers, can develop more desired functional lipid such as α-tocopherol nanoemulsions for various water-based food and pharmaceutical uses.

Preparation and characterization of α-tocopherol nanocapsules based on gum Arabic-stabilized nanoemulsions

The preparation of water dispersed α-tocopherol nanocapsules through solvent-displacement technique using gum Arabic (GA) as natural stabilizing and emulsifying biopolymer, for a first time was aimed in current research. The effects of GA concentrations on physicochemical and biological characteristics of prepared nanocapsules, namely, mean particle size, size distribution, zeta potential, rheological properties, turbidity, in vitro antioxidant activity and cellular uptake were evaluated, subsequently. The result indicated that the mono modal size distributed water dispersible α-tocopherol nanocapsules could be successfully attained using selected technique in sizes ranged from 10.01 to 171.2 nm and zeta potential of - 13.5 to - 47.8 mv. The prepared nanocapsules showed the dilatant rheological properties and acceptable radical scavenging (antioxidant activity). The cellular uptake of samples were increased up to 12 times more than microsized α-tocopherol. Consequently, the prepared water dispersed nanosized α-tocopherol can effectively be used in water based food and beverage formulations as nutrition enhancer or natural preservatives.

Physicochemical Properties of Whey-Protein-Stabilized Astaxanthin Nanodispersion and Its Transport via a Caco-2 Monolayer

Astaxanthin nanodispersion was prepared using whey protein isolate (WPI) and polymerized whey protein (PWP) through an emulsification-evaporation technique. The physicochemical properties of the astaxanthin nanodispersion were evaluated, and the transport of astaxanthin was assessed using a Caco-2 cell monolayer model. The astaxanthin nanodispersions stabilized by WPI and PWP (2.5%, w/w) had a small particle size (121 ± 4.9 and 80.4 ± 5.9 nm, respectively), negative ζ potential (-19.3 ± 1.5 and -35.0 ± 2.2 mV, respectively), and high encapsulation efficiency (92.1 ± 2.9 and 93.5 ± 2.4%, respectively). Differential scanning calorimetry curves indicated that amorphous astaxanthin existed in both astaxanthin nanodispersions. Whey-protein-stabilized astaxanthin nanodispersion showed resistance to pepsin digestion but readily released astaxanthin after trypsin digestion. The nanodispersions showed no cytotoxicity to Caco-2 cells at a protein concentration below 10 mg/mL. WPI- and PWP-stabilized nanodispersions improved the apparent permeability coefficient (P_app) of Caco-2 cells to astaxanthin by 10.3- and 16.1-fold, respectively. The results indicated that whey-protein-stabilized nanodispersion is a good vehicle to deliver lipophilic bioactive compounds, such as astaxanthin, and to improve their bioavailability.

Anti-inflammatory effects of astaxanthin in the human gingival keratinocyte line NDUSD-1

Oral lichen planus is a chronic inflammatory disease that affects the mucous membrane of the oral cavity and can contribute to the development of other diseases. Inflammation in oral lichen planus is a T-cell-mediated autoimmune disease that acts through cytotoxic CD8⁺ T cells to trigger apoptosis of keratinocytes. However, the specific cause of oral lichen planus remains unknown and no effective medical treatment has yet been established. Astaxanthin is a carotenoid pigment with capacity for anti-inflammatory and anti-oxidant activities. In this study, we evaluated whether astaxanthin could be used to improve the pathology of oral lichen planus by reducing inflammation. In particular, the anti-inflammatory effects of astaxanthin on the chronic inflammation caused by lipopolysaccharide derived from Escherichia coli O55 in human gingival keratinocytes (NDUSD-1) were evaluated. Following astaxanthin treatment, localization of nuclear factor κB/p65 and the level of inflammatory cytokines (interleukin-6, tumor necrosis factor-α) tended to decrease, and cell proliferation significantly increased in vitro. These results suggest that astaxanthin could be useful for improving chronic inflammation such as that associated with oral lichen planus.