Chitosan-glycolipid nanocarriers improve the bioavailability of fucoxanthin via up-regulation of PPARγ and SRB1 and antioxidant activity in rat model

Recent advancement in protected delivery methods for carotenoid: a smart choice in modern nutraceutical formulation concept

Carotenoids are fat-soluble bio pigments often responsible for red, orange, pink and yellow coloration of fruits and vegetables. They are commonly referred as nutraceutical which is an alternative to pharmaceutical drugs claiming to have numerous physiological benefits. However their activity often get disoriented by photonic exposure, temperature and aeration rate thus leading to low bioavailability and bio accessibility. Most of the market value for carotenoids revolves around food and cosmetic industries as supplement where they have been continuously exposed to rigorous physico-chemical treatment. Though several encapsulation techniques are now in practice to improve stability of carotenoids, the factors like shelf life during storage and controlled release from the delivery vehicle always appeared to be a bottleneck in this field. In this situation, different technologies in nanoscale is showing promising result for carotenoid encapsulation and delivery as they provide greater mass per surface area and protects most of their bioactivities. However, safety concerns related to carrier material and process must be evaluated crucially. Thus, the aim of this review was to collect and correlate technical information concerning the parameters playing pivotal role in characterization and stabilization of designed vehicles for carotenoids delivery. This comprehensive study predominantly focused on experiments carried out in past decade explaining how researchers have fabricated bioprocess engineering in amalgamation with nano techniques to improve the bioavailability for carotenoids. Furthermore, it will help the readers to understand the cognisance of carotenoids in nutraceutical market for their trendy application in food, feed and cosmeceutical industries in contemporary era.

The pro-absorptive effect of glycosylated zein-fatty acid complexes on fucoxanthin via the lipid transporter protein delivery pathway

Growing research confirms that lipid transport proteins play a key role in the trans-intestinal epithelial transport of carotenoids. In this study, to simultaneously improve the digestive stability and intestinal absorption of fucoxanthin (FX), functionalized vectors with a capability of up-regulating the expression of FX-specific lipid transporter proteins was fabricated. The results showed that myristic acid, palmitic acid, and stearic acid effectively promoted FX-specific lipid transporter protein expression and formed stable self-assembly complexes with Millard-modified zein (MZ). The FX was sufficiently encapsulated in the MZ-fatty acid (FA) particles, forming spherical nanoparticles with a "core-shell" structure. Simulated gastrointestinal digestion showed that FA introduction significantly increased the FX bioaccessibility. In vivo results further verified that adding FAs dramatically increased the FX serum response concentration. These findings suggest that incorporating nutrients that can promote lipid transporter protein expression into delivery vehicles should be an effective strategy for improving oral carotenoid absorption.

Fucoxanthin, a Functional Food Ingredient: Challenges in Bioavailability

PURPOSE OF REVIEW

Fucoxanthin is an orange-red xanthophyll carotenoid found in brown seaweeds and known for its many bioactive properties. In recent years, the bioactive properties of fucoxanthin have been widely explored, making it a compound of immense interest for various health applications like anti-cancer, anti-tumour, anti-diabetic and anti-obesity properties. However, the poor bioavailability and instability of fucoxanthin in the gastrointestinal tract have major limitations. Encapsulation is a promising approach to overcome these challenges by enclosing fucoxanthin in a protective layer, such as liposomes or nano-particles. Encapsulation can improve the stability of fucoxanthin by protecting it from exposure to heat, pH, illumination, gastric acids and enzymes that can accelerate its degradation.

RECENT FINDINGS

Studies have shown that lipid-based encapsulation systems such as liposomes or nano-structured lipid carriers may solubilise fucoxanthin and enhance its bioavailability (from 25 to 61.2%). In addition, encapsulation can also improve the solubility of hydrophobic fucoxanthin, which is important for its absorption and bioavailability. This review highlights the challenges involved in the absorption of fucoxanthin in the living system, role of micro- and nano-encapsulation of fucoxanthin and their potential to enhance intestinal absorption.

Dietary Protective Potential of Fucoxanthin as an Active Food Component on Neurological Disorders

The prevalence of neurodegenerative, cerebrovascular, and psychiatric diseases and other neurological disorders has increased dramatically worldwide. Fucoxanthin is an algal pigment with many biological functions, and there is rising evidence that fucoxanthin plays a preventive and therapeutic role in neurological disorders. This review focuses on the metabolism, bioavailability, and blood-brain barrier penetration of fucoxanthin. Furthermore, the neuroprotective potential of fucoxanthin in neurodegenerative diseases, cerebrovascular diseases, and psychiatric diseases as well as other neurological disorders such as epilepsy, neuropathic pain, and brain tumors by acting on multiple targets will be summarized. The multiple targets include regulating apoptosis, reducing oxidative stress, activating the autophagy pathway, inhibiting Aβ aggregation, improving dopamine secretion, reducing α-synuclein aggregation, attenuating neuroinflammation, modulating gut microbiota, and activating brain-derived neurotrophic factor, etc. Additionally, we look forward to brain-targeted oral transport systems due to the low bioavailability and blood-brain barrier permeability of fucoxanthin. We also propose exploring the systemic mechanisms of fucoxanthin metabolism and transport through the gut-brain process and envision new therapeutic targets for fucoxanthin to act on the central nervous system. Finally, we propose dietary fucoxanthin delivery interventions to achieve preventive effects on neurological disorders. This review provides a reference for the application of fucoxanthin in the neural field.

Delivery systems for fucoxanthin: Research progress, applications and future prospects

Fucoxanthin is a special kind of keto-carotenoid found only in algae. The unique structure of fucoxanthin endows it with extraordinary biological activities, which are of great significance to improve food quality and enhance human health. However, due to its highly unsaturated structure, fucoxanthin also suffers from some limitations, such as instability, poor water solubility and low bioavailability. Therefore, although its content is relatively abundant, its applications in the food industry are extremely scarce. In recent years, there have been many reports on the preparation and characterization of delivery systems for fucoxanthin. These well-designed delivery systems can efficaciously alleviate the instability of fucoxanthin under adverse conditions, thereby improving its oral bioavailability. Thus, this review emphatically summarizes the delivery systems that are widely used to encapsulate, protect and release fucoxanthin. Besides, the influence of delivery systems on the absorption of fucoxanthin by intestinal epithelial cells is highlighted. The applications and future development trends of delivery systems for fucoxanthin are also discussed. The extraction of fucoxanthin, development of novel delivery systems, sensory evaluation and toxicity studies, and industrial production may be promising research directions in the future. Overall, this review provides guidance for the development of fucoxanthin-loaded delivery systems.

Brown algae and barley-based anti-obesity food and its safety in C57BL6 mice

Brown algae have been considered a potential source of bioactives and used as a dietary supplement to manage obesity and its associated health complications. However, its effective use is limited due to heavy metals and microbial contamination, unawareness of health benefits and limited dietary exploitation. We developed, the Indian brown algae Padina tetrastromatica and barley-based anti-obesity food (AOF) and examined for microbial and heavy metal safety. Additionally, acute [0 (control), 50, 100, 200, 500 g AOF/kg diet] and sub-acute [0, 5, 50 g AOF/kg diet] doses of AOF were fed to C57BL6 mice and toxicity was examined. The physical, locomotory, hematological, biochemical parameters and histopathology were examined. Postprandial plasma and tissue levels of fucoxanthin and its metabolites were analyzed. Feeding AOF did not affect the general behavior, food and water intake, growth or survival of animals. Biochemical indices did not show any differences between AOF-fed and control groups. However, significantly lower levels of plasma cholesterol and triglycerides in groups fed 5 and 50 g of AOF/kg diet were observed. The post-mortem examination revealed no macroscopic/microscopic alteration in the vital organs. Overall, results validate that AOF is a safe and effective dietary supplement (even at higher doses of 500 g AOF/kg) to mitigate obesity.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-022-05483-4.

Mechanisms of carotenoid intestinal absorption and the regulation of dietary lipids: lipid transporter-mediated transintestinal epithelial pathways

Dietary lipids are key ingredients during cooking, processing, and seasoning of carotenoid-rich fruits and vegetables, playing vitals in affecting the absorption and utilization of carotenoids for achieving their health benefits. Besides, dietary lipids have also been extensively studied to construct various delivery systems for carotenoids, such as micro/nanoparticles, micro/nanoemulsions, and liposomes. Currently, the efficacies of these techniques on improving carotenoid bioavailability are often evaluated using the micellization rate or "bioaccessibility" based on in vitro models. However, recent studies have found that dietary lipids may also affect the carotenoid uptake via intestinal epithelial cells and the efflux of intracellular chyle particles via lipid transporters. An increasing number of studies reveal the varied impact of different dietary lipids on the absorption of different carotenoids and some lipids may even have an inhibitory effect. Consequently, it is necessary to clarify the relationship between the addition of dietary lipids and the intestinal absorption of carotenoid to fully understand the role of lipids during this process. This paper first introduces the intestinal absorption mechanism of carotenoids, including the effect of bile salts and lipases on mixed micelles, the types and regulation of lipid transporters, intracellular metabolizing enzymes, and the efflux process of chyle particles. Then, the regulatory mechanism of dietary lipids during intestinal carotenoid absorption is further discussed. Finally, the importance of selecting the dietary lipids for the absorption and utilization of different carotenoids and the design of an efficient delivery carrier are emphasized. This review provides suggestions for precise dietary carotenoid supplementation and offere an important reference for constructing efficient transport carriers for liposoluble nutrients.

Construction of lipid-biomacromolecular compounds for loading and delivery of carotenoids: Preparation methods, structural properties, and absorption-enhancing mechanisms

Due to the unstable chemical properties and poor water solubility of carotenoids, their processing adaptation and oral bioavailability are poor, limiting their application in hydrophilic food systems. Lipid-biomacromolecular compounds can be excellent carriers for carotenoid delivery by taking full advantage of the solubilization of lipids to non-polar nutrients and the water dispersion and gastrointestinal controlled release properties of biomacromolecules. This paper reviewed the research progress of lipid-biomacromolecular compounds as encapsulation and delivery carriers of carotenoids and summarized the material selection and preparation methods for biomacromolecular compounds. By considering the interaction between the two, this paper briefly discussed the effect of these compounds on carotenoid water solubility, stability, and bioavailability, emphasizing their delivery effect on carotenoids. Finally, various challenges and future trends of lipid-biomacromolecular compounds as carotenoid delivery carriers were discussed, providing new insight into efficient loading and delivery of carotenoids.

Fabricating hydrophilic fatty acid-protein particles to encapsulate fucoxanthin: Fatty acid screening, structural characterization, and thermal stability analysis

Biomacromolecules are used to encapsulate carotenoids, but their poor absorption-enhancing ability restricts their application. This study integrated dietary fatty acids (FAs) into the protein-based encapsulation of fucoxanthin (FUCO) due to its positive role in carotenoid absorption. The results showed that of the 14 tested FAs, only myristic, palmitic, stearic, oleic, linoleic, and docosahexaenoic acid obviously promoted FUCO absorption. FAs were employed for FUCO encapsulation using bovine serum albumin (BSA) to fabricate FUCO-FA-BSA systems, with an encapsulation efficiency of > 98%, a particle size ranging from 113.1 nm to 193.5 nm, and a Zeta-potential between -32.8 mV and -38.3 mV. Electron microscopy and Fourier transform infrared spectroscopy revealed complete FUCO encapsulation, while the FUCO-loading particles exhibited a "core-shell" structure. The retention rate of the encapsulated FUCO increased 2.16-4.06 times when heated at 80.0 °C for 200 min. These results suggested that FA-BSA complexes might provide a promising strategy for embedding carotenoids.

Natural Antioxidant Evaluation: A Review of Detection Methods

Antioxidants have drawn the attention of the scientific community due to being related to the prevention of various degenerative diseases. The antioxidant capacity has been extensively studied in vitro, and different methods have been used to assess its activity. However, the main issues related to studying natural antioxidants are evaluating whether these antioxidants demonstrate a key role in the biological system and assessing their bioavailability in the organism. The majority of outcomes in the literature are controversial due to a lack of method standardization and their proper application. Therefore, this study aims to compile the main issues concerning the natural antioxidant field of study, comparing the most common in vitro methods to evaluate the antioxidant activity of natural compounds, demonstrating the antioxidant activity in biological systems and the role of the main antioxidant enzymes of redox cellular signaling and explaining how the bioavailability of bioactive compounds is evaluated in animal models and human clinical trials.

Xanthophylls from the Sea: Algae as Source of Bioactive Carotenoids

Algae are considered pigment-producing organisms. The function of these compounds in algae is to carry out photosynthesis. They have a great variety of pigments, which can be classified into three large groups: chlorophylls, carotenoids, and phycobilins. Within the carotenoids are xanthophylls. Xanthophylls (fucoxanthin, astaxanthin, lutein, zeaxanthin, and β-cryptoxanthin) are a type of carotenoids with anti-tumor and anti-inflammatory activities, due to their chemical structure rich in double bonds that provides them with antioxidant properties. In this context, xanthophylls can protect other molecules from oxidative stress by turning off singlet oxygen damage through various mechanisms. Based on clinical studies, this review shows the available information concerning the bioactivity and biological effects of the main xanthophylls present in algae. In addition, the algae with the highest production rate of the different compounds of interest were studied. It was observed that fucoxanthin is obtained mainly from the brown seaweeds Laminaria japonica, Undaria pinnatifida, Hizikia fusiformis, Sargassum spp., and Fucus spp. The main sources of astaxanthin are the microalgae Haematococcus pluvialis, Chlorella zofingiensis, and Chlorococcum sp. Lutein and zeaxanthin are mainly found in algal species such as Scenedesmus spp., Chlorella spp., Rhodophyta spp., or Spirulina spp. However, the extraction and purification processes of xanthophylls from algae need to be standardized to facilitate their commercialization. Finally, we assessed factors that determine the bioavailability and bioaccesibility of these molecules. We also suggested techniques that increase xanthophyll’s bioavailability.

Oxidative Stress and Marine Carotenoids: Application by Using Nanoformulations

Carotenoids are natural fat-soluble pigments synthesized by plants, algae, fungi and microorganisms. They are responsible for the coloration of different photosynthetic organisms. Although they play a role in photosynthesis, they are also present in non-photosynthetic plant tissues, fungi, and bacteria. These metabolites have mainly been used in food, cosmetics, and the pharmaceutical industry. In addition to their utilization as pigmentation, they have significant therapeutically applications, such as improving immune system and preventing neurodegenerative diseases. Primarily, they have attracted attention due to their antioxidant activity. Several statistical investigations indicated an association between the use of carotenoids in diets and a decreased incidence of cancer types, suggesting the antioxidant properties of these compounds as an important factor in the scope of the studies against oxidative stress. Unusual marine environments are associated with a great chemical diversity, resulting in novel bioactive molecules. Thus, marine organisms may represent an important source of novel biologically active substances for the development of therapeutics. Marine carotenoids (astaxanthin, fucoxanthin, β-carotene, lutein but also the rare siphonaxanthin, sioxanthin, and myxol) have recently shown antioxidant properties in reducing oxidative stress markers. Numerous of bioactive compounds such as marine carotenoids have low stability, are poorly absorbed, and own very limited bioavailability. The new technique is nanoencapsulation, which can be used to preserve marine carotenoids and their original properties during processing, storage, improve their physiochemical properties and increase their health-promoting effects. This review aims to describe the role of marine carotenoids, their potential applications and different types of advanced nanoformulations preventing and treating oxidative stress related disorders.

Aggregation of Fucoxanthin and Its Effects on Binding and Delivery Properties of Whey Proteins

In this study, aggregation of fucoxanthin (FX) and its effects on binding and delivery properties of whey proteins were explored. Initially, the H- and J-aggregates of FX were successfully prepared by adjusting the water/ethanol ratio and water-dripping rate. The transition from J- to H-aggregates was observed over the standing time. Then, the molecular arrangement of FX H-aggregates was analyzed using the point-dipole approximation model and molecular dynamics, showing that their intermolecular distance and angle were about 5.0-6.7 Å and -35° to 35°, respectively. The transformation of J- to H-aggregates was also observed during molecular dynamics, with a shortened intermolecular distance, a reduced solvent accessible surface area, an enhanced interaction force, and a narrowed dihedral angle. Further, the interactions of whey proteins with different forms of FX were investigated, indicating that both β-lactoglobulin and whey protein isolates could form complexes with the monomers, H-aggregates, and J-aggregates of FX. In terms of affinity, whey proteins bound FX monomers more strongly than aggregates. Furthermore, the complexes comprising whey proteins and monomeric FX had better delivery capabilities than aggregated FX, manifested in encapsulation efficiency, physical stability, and bioaccessibility.

Oleic acid as a protein ligand improving intestinal absorption and ocular benefit of fucoxanthin in water through protein-based encapsulation

The oleic acid–protein delivery system can improve both the dispersibility and intestinal absorption of fucoxanthin in a hydrophilic environment.

Bioaccessibility of Marine Carotenoids

The benefit of carotenoids to human health is undeniable and consequently, their use for this purpose is growing rapidly. Additionally, the nutraceutical properties of carotenoids have attracted attention of the food industry, especially in a new market area, the 'cosmeceuticals.' Marine organisms (microalgae, seaweeds, animals, etc.) are a rich source of carotenoids, with optimal properties for industrial production and biotechnological manipulation. Consequently, several papers have reviewed the analysis, characterization, extraction and determination methods, biological functions and industrial applications. But, now, the bioaccessibility and bioactivity of marine carotenoids has not been focused of any review, although important achievements have been published. The specific and diverse characteristic of the marine matrix determines the bioavailability of carotenoids, some of them unique in the nature. Considering the importance of the bioavailability not just from the health and nutritional point of view but also to the food and pharmaceutical industry, we consider that the present review responds to an actual demand.

Polymeric chitosan-glycolipid nanocarriers for an effective delivery of marine carotenoid fucoxanthin for induction of apoptosis in human colon cancer cells (Caco-2 cells)

Fucoxanthin (FUCO), a marine carotenoid is photo-, and thermo-labile and poorly bioavailable due to its lipophilicity. Hence, we developed a chitosan (CS) + glycolipid (GL) nanogels (NGs) to increase cellular uptake and anticancer efficacy of FUCO (10 μM) in human colon cells (Caco-2). Effect of FUCO loaded in NGs with/with no GL was studied in comparison with micellar FUCO. Results showed that the cell viability was lower (p < 0.05) in NGs + GL (50.5%) compared to NGs (-GL) (66.5%) and the mixed micelles (72.5%) groups over 48 h exposure. An enhanced reactive oxygen species (ROS) generation was evident in NGs + GL (379.2%) group compared to NGs (-GL) and mixed micelles groups. Further, induction of apoptosis with an increased chromatin condensation and DNA fragmentation as evidenced in DAPI staining and DNA ladder assay were higher in NGs + GL group than other groups. Down-regulation of Bcl-2 (6.6 folds) was higher in NGs + GL group compared to NGs (-GL) (1.94 fold) and mixed micelles (1.19 fold) groups. Higher Bax up-regulation in NGs + GL compared to other groups supports the Bcl-2 down regulation. Mitochondrial membrane polarisation (ΔΨ_m) was higher in NGs + GL group (2.46 fold) compared to NGs (-GL) (1.91 fold) and mixed micelles (1.26 fold) groups. The cellular FUCO uptake illustrated a positive correlation between its level (pmol/10⁶ cells) in NGs + GL (758.3) and enhanced caspase-3 activity (25.8 folds). This could be the reason for an increased apoptotic activity in NGs + GL group than other groups. Results demonstrate that delivery of FUCO in NGs + GL carrier aids cellular uptake and chemotherapeutic potential of FUCO. Results further demonstrate, for the first time, higher anti-cancer activity of FUCO loaded in NGs + GL and the effect was through ROS generation via a caspase dependent mechanism in Caco-2 cells.