Inflammation is a fundamental physiological response that acts as the body’s initial defense mechanism against threats such as pathogens, cellular injury, and irritants. While acute inflammation plays a vital role in tissue repair and the restoration of normal function, persistent or chronic inflammation is associated with the development of numerous diseases, including cancer, cardiovascular illnesses, neurodegenerative disorders, and autoimmune disorders [1,2,3,4].

The complex inflammatory cascade involves multiple signaling pathways and mediators that orchestrate both the initiation and resolution of the inflammatory response. When dysregulated, these pathways contribute significantly to tissue damage and disease progression [5,6]. Current therapeutic approaches primarily rely on non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids, which, despite their efficacy, are associated with considerable adverse effects during prolonged use, including gastrotoxicity, cardiovascular complications, and immunosuppression [7,8]. This therapeutic challenge has intensified the search for natural bioactive compounds with broad-spectrum anti-inflammatory properties and improved safety profiles.

Astaxanthin is a red-orange keto-carotenoid (C₄₀H₅₂O₄) belonging to the carotenoid family, distinguished by its extended chain of conjugated double bonds and terminal β-ionone rings, as well as the presence of both hydroxyl and ketone functional groups at positions 3 and 4 on each end of the molecule. This unique molecular structure not only imparts astaxanthin with its characteristic intense red color but also contributes to its potent antioxidant properties [9,10].  Naturally, astaxanthin is synthesized by microalgae such as Haematococcus pluvialis, yeast (Xanthophyllomyces dendrorhous), and certain bacteria, and it accumulates in aquatic animals like salmon, trout, krill, and especially crustaceans,   where   it    is   responsible   for   the  reddish coloration of their shells and tissues [11,12, 13,14].  In crustaceans such as shrimp, astaxanthin is predominantly found in the shell rather than the flesh, becoming visually prominent after cooking as the pigment is released from protein complexes [15]. 

Astaxanthin has emerged as a particularly promising anti-inflammatory agent. Characterized by its distinctive molecular structure featuring a polyene chain with 13 conjugated double bonds and terminal β-ionone, astaxanthin exhibits exceptional antioxidant capacity-significantly stronger than other carotenoids and conventional antioxidants like vitamin E and vitamin C [16,17,18].  This structural uniqueness confers astaxanthin with distinctive pharmacological properties, including remarkable stability within cellular membranes and superior reactive oxygen species (ROS) scavenging abilities [19]. 

The anti-inflammatory mechanisms of astaxanthin have been partially elucidated through both in vitro and in vivo experimental models [20, 21,22, 23].  Research has demonstrated that astaxanthin effectively inhibits nitric oxide (NO) production and intracellular reactive oxygen and nitrogen species (RONS) in a dose-dependent manner. Furthermore, astaxanthin suppresses the hydrogen peroxide-induced activation of nuclear factor kappa B (NF-κB) and inhibits inducible nitric oxide synthase (iNOS) expression, consequently reducing pro-inflammatory cytokine production, including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) [24, 25].

Computational approaches have significantly advanced our understanding of astaxanthin's molecular interactions. Recent network pharmacology analyses, molecular docking simulations, and molecular dynamics studies have begun to elucidate the structural basis for astaxanthin's interactions with inflammatory mediators. However, comprehensive characterization of the specific structural features that facilitate astaxanthin's simultaneous inhibition of multiple inflammatory pathways remains incomplete. In this study, a green method was developed for the extraction of astaxanthin from shrimp by-products, then the anti-inflammatory activity was explored with in vitro and in silico tests.

Preparation of Shrimp Waste Powder

Shrimp waste from Aristeus antennatus-including heads, shells, and tails-was collected from fisheries in Mostaganem (Algeria). The waste was transported to the laboratory, and was thoroughly washed several times with tap water to remove impurities, then freeze-dried. The dried material was ground and sieved to obtain a fine powder with a particle size of 0.5 mm. The resulting shrimp waste powder was stored at –4°C until further use.

Oil Extraction of Astaxanthin

Five different vegetable oils (argan, coconut, sunflower, industrial olive oil, and traditional olive oil) were evaluated for their efficiency in extracting astaxanthin. The extraction procedure was based on the method described by Sachindra and Mahendrakar [26], with minor modifications. One gram of shrimp by-product powder was mixed with 5 mL of the selected vegetable oil. The mixture was vortexed thoroughly to ensure homogenization, then incubated in a water bath at 60°C for 1 hour. After incubation, the mixture was filtered through Whatman filter paper and subsequently centrifuged at 4,000 rpm for 20 minutes. The pigmented oil phase was carefully collected.

Based on the initial screening, the oils yielding the highest carotenoid content were selected for further optimization. Extraction parameters including solid-liquid ratio (1:5, 1:10, and 1:15 w/v), temperature (50°C, 60°C, and 70°C), and extraction time (30, 60, and 90 minutes) were assessed. This systematic approach allowed us to determine the optimal conditions for maximizing carotenoid recovery from shrimp by-products.

Spectrophotometric Determination of Astaxanthin Content

The astaxanthin content of each extract was determined using UV-Vis spectrophotometric analysis. Quantification was performed by measuring the absorbance of the samples at 476 nm, and concentrations were calculated using linear calibration equations as described by Asker et al. [27]. The results were expressed as micrograms of astaxanthin per gram of shrimp waste, and all measurements were carried out in triplicate.

In Vitro Anti-inflammatory Activity of Astaxanthin

The anti-inflammatory potential of astaxanthin extract was assessed using a bovine serum albumin (BSA) denaturation inhibition assay, modified from established protocols. Briefly, 1 mL aliquots of test compounds at varying concentrations were mixed with 1 mL of 1 mM BSA solution prepared in phosphate buffer (pH 6.4). After 15 minutes, the mixture was heated at 70 ± 1°C for 10 minutes. Post-cooling, the absorbance was measured at 660 nm. Diclofenac (20 mg/kg body weight) served as the reference standard [28]. The percentage inhibition of denaturation was calculated using:

Inhibition (%) = ((A_sample- A_control)/ A_control) ×100

In Silico Anti-inflammatory Activity of Astaxanthin

NF-κB Inhibition by Astaxanthin

Molecular Docking Protocol: Molecular docking was performed using the online CB-Dock platform. The docking parameters were set with a grid size of 38×38×38 Å and an RMSD clustering threshold of 2.0 Å. The protein structure used as the target was the p50/p65 subunit of NF-κB (PDB: 1NFI), which plays a key role in the regulation of inflammatory processes.

Binding Pocket Analysis

Potential binding sites on the NF-κB protein were identified using the CASTp tool. CASTp allows for the localization and characterization of protein cavities by calculating their volumes and geometric coordinates, thus facilitating the precise targeting of possible interactions with astaxanthin.

COX-2 Inhibition by Astaxanthin

Molecular Docking Protocol: Molecular interaction modeling was performed using the CB-Dock platform with the following parameters: Crystallographic structure: Human COX-2 (PDB: 5U7N), prepared by removing water molecules and adding polar hydrogens. Grid dimensions: 38 × 38 × 38 Å centered on the catalytic site (coordinates derived from CASTp analysis). Execution parameters: 10 independent docking runs with pose clustering (RMSD threshold ≤ 2.0 Å). Validation: Redocking of the native ligand (arachidonic acid) to verify protocol accuracy (RMSD < 1.5 Å).

Structural Analysis

Molecular interactions were characterized using: PyMOL (v2.5): For 3D visualization of ligand-protein complexes and rendering of key residues (e.g., TYR385, ARG120). LigPlot+ (v2.2): To generate 2D interaction diagrams, mapping hydrogen bonds, hydrophobic contacts, and van der Waals interactions. CASTp (v3.0): For quantitative analysis of binding pocket geometry, including volume calculation (ų) and identification of catalytic residues.

ADMET Prediction

The pharmacokinetic and toxicological properties of astaxanthin were evaluated in silico using the SwissADME and pkCSM platforms. The parameters assessed included intestinal absorption, blood-brain barrier (BBB) permeability, and the potential for interaction with cytochrome P450 (CYP) isoenzymes. SwissADME provides robust predictions for gastrointestinal absorption (BOILED-Egg model), membrane permeability, and CYP inhibition, while pkCSM employs molecular signatures to estimate absorption, distribution, metabolism, excretion, and toxicity. These complementary tools enabled the generation of a comprehensive and reliable ADMET profile for astaxanthin, which is essential for evaluating its potential as an anti-inflammatory agent.

RESULTS

Astaxanthin Extraction Method Development

The extraction of astaxanthin from shrimp by-products showed a significant variation among the tested vegetable oils (table1). Sunflower oil yielded the highest carotenoid content (240 ± 14.04 µg/g), followed by coconut oil (233 ± 10.44 µg/g) and traditional olive oil (220.91 ± 9.5 µg/g). In contrast, argan oil exhibited the lowest extraction efficiency, with a yield of 133.59 ± 6.37 µg/g. Sachindra et al. [26] compared the extraction efficiency of different vegetable oils on astaxanthin extraction from pink shrimps (sunflower oil, groundnut oil, gingelly oil, mustard oil, soy oil, coconut oil and rice bran oil). Sunflower oil provided the highest yield of astaxanthin (26.3 µg/g). The solubility and extraction efficiency of carotenoids in vegetable oils are determined by several factors,  including  oil  density, viscosity, and polarity [29].

Table 1: Carotenoid content in different vegetable oils from shrimp waste

Parjikolaei et al. [30] demonstrated that the high efficiency of sunflower oil is mainly due to its low viscosity, which allows the oil to penetrate shrimp waste more effectively, thereby increasing the diffusion coefficient and facilitating the transfer of astaxanthin into the oil phase.

Effect of Solid-Liquid Ratio

Astaxanthin content increased as the solid-to-liquid ratio varied from 1:5 to 1:10, reaching a maximum yield of 264.96 µg/g (Figure 1A). However, further increasing the ratio to 1:20 did not enhance significantly the astaxanthin yield (ρ≥ 0.O5). This suggests that a moderate solid-to-liquid ratio (1:10) optimizes extraction, likely by balancing solvent availability for efficient pigment diffusion without excessive dilution. These findings align with Parjikolaei et al. [30], who tested sunflower oil at liquid-to-waste ratios of 1:3, 1:6, and 1:9 (v/w), observing peak extraction at 1:9. Higher ratios improve solvent penetration into cell matrices, enhancing mass transfer coefficients [31]. Similarly, Zhao et al. [32] demonstrated that increasing the oil-to-waste ratio directly improved both pigment extraction rates and oil recovery, identifying it as a critical parameter for maximizing astaxanthin yield. Collectively, these studies underscore the importance of optimizing solvent-to-solid ratios to achieve efficient carotenoid extraction.

Effect of Extraction Temperature

The effect of extraction temperature on astaxanthin yield is clearly depicted in Figure 1B. Astaxanthin content increased from approximately 223.39 µg/g at 50 °C to a maximum of 264.96 µg/g at 60 °C, indicating that moderate heating enhances the efficiency of pigment extraction, likely by improving solvent penetration and mass transfer with the reduction of oil viscosity [33]. However, a further increase in temperature to 70 °C resulted in a marked decline in astaxanthin content to around 88.50 µg/g. This sharp decrease at higher temperature suggests significant thermal degradation of astaxanthin, which is known to be sensitive to heat. It could be explained also by the formation of peroxides, resulting from the oxidation of the oil at high temperatures and the consequent reduction in the quality and quantity of extracted compounds [34]. These results underscore the importance of optimizing extraction temperature, with 60 °C identified as the optimal condition for maximizing astaxanthin recovery while minimizing pigment loss due to thermal breakdown.

Effect of the Extraction Time

Figure 1C demonstrates the critical role of extraction time on astaxanthin yield from shrimp by-products. The results
reveal a pronounced time-dependent pattern, with astaxanthin content increasing from 102.75 μg/g at 30 minutes to a maximum yield of approximately 264.96 μg/g at 60 minutes. However, extending the extraction time to 90 minutes resulted in a significant decline in astaxanthin content to approximately 122.88 μg/g. This suggests that optimal extraction requires sufficient time for complete solvent penetration and pigment solubilization, but excessive exposure time under heating temperatures leads to the oxidation and the degradation of the extracted astaxanthin. These findings highlight the importance of precise time control during the extraction process, with 60 minutes representing the optimal extraction duration that balances maximum pigment recovery with minimal degradation.

Salazar-González et al. [35] showed that a longer contact time between the matrix and the sunflower oil resulted in greater interaction between the particles, and consequently, a higher concentration of carotenoids in the extracts.  Rudi et al. [36] Confirmed in their study that after 180 min at a temperature of 60°C, the astaxanthin extract in vegetable oils oxidises due to the oxidation of the fatty acids. In addition, vegetable oil begins to oxidise after a certain period of time, and the loss of volatile elements can lead to a decrease in the amount of oil containing astaxanthin. Ahmadkelayeh et al. [37] confirmed that at higher temperatures, the astaxanthin yield starts to decrease with increasing extraction time.

In Vitro Anti-Inflammatory Effect of Astaxanthin Extract

In the in vitro model for assessing anti-inflammatory activity, the inhibitory effect of astaxanthin extracted from shrimp waste and diclofenac of albumin denaturation was assessed. Both compounds demonstrate a clear concentration-dependent inhibitory effect across the tested range (15-250 μg/mL) (Figure 2). Diclofenac, a standard non-steroidal anti-inflammatory drug, consistently exhibits superior inhibitory potential compared to astaxanthin. At 250 μg/mL, diclofenac achieved approximately 80% inhibition, whereas astaxanthin reached approximately 64% inhibition. The dose-response curves for both compounds show similar patterns, with steeper increases observed at lower concentrations (15-50 μg/mL) followed by more gradual increases at higher concentrations, suggesting approaching saturation kinetics. These findings indicate that while astaxanthin possesses significant anti-denaturation activity, its potency remains lower than that of the reference drug diclofenac. Nevertheless, the substantial inhibitory effect demonstrated by astaxanthin suggests its potential as a natural anti-inflammatory agent, which could be particularly valuable in contexts where alternatives to synthetic drugs are sought.

Astaxanthin has demonstrated significant potential in alleviating both chronic and acute inflammation across a range of diseases. Experimental studies have shown its beneficial effects in models of neurodegenerative disorders, diabetes, gastrointestinal diseases, renal inflammation,   as    well    as    skin    and    eye     conditions

Figure 1: The effect of (A) solid-liquid ratio, (B) temperature, and (C) the extraction time on astaxanthin content

[21,38,25]. These findings highlight astaxanthin as a promising candidate for the treatment of inflammation-related diseases. Many in vitro and in vivo studies have demonstrated the anti-inflammatory effects of astaxanthin [22, 24,39,40]. In vitro, astaxanthin has been shown to suppress the production of key pro-inflammatory mediators such as nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor-alpha (TNF-α) in macrophage cell lines, indicating a dose-dependent anti-inflammatory effect by directly inhibiting inducible nitric oxide synthase (iNOS) activity and inflammatory cytokine production [39,41]. In vivo studies, such as those involving endotoxin-induced uveitis in rats, confirmed that astaxanthin reduces inflammatory cell infiltration and protein concentration in aqueous humor, with effects comparable to prednisolone. Additionally, astaxanthin modulates inflammatory pathways by suppressing NF-κB activation, which downregulates pro-inflammatory  genes  including  IL-1β,  IL-6,  TNF-α,  iNOS, and cyclooxygenase-2 (COX-2), contributing to its anti-inflammatory and antioxidant properties [22, 24, 39,40].

Figure 2: Dose-Dependent Inhibition of Albumin Denaturation by Astaxanthin and Diclofenac

Figure 3: Selectivity of the C4 Pocket-Surface Representation of the NF-κB - Astaxanthin

In Silico Anti-inflammatory Activity of Astaxanthin

Structural and Mechanistic Analysis of NF-κB Inhibition

Selectivity of the C4 Pocket: The C4 pocket of NF-κB, characterized by its reduced volume (462 ų), exhibits exceptional affinity for astaxanthin, as demonstrated by a Vina docking score of -7.9 kcal/mol (Figure 3). This remarkable selectivity is explained by several key factors:  Optimal Steric Complementarity: The rigid structure of astaxanthin, featuring 13 conjugated double bonds, fits precisely into the compact geometry of the C4 pocket. This molecular adaptation minimizes steric clashes and maximizes favorable contacts, supporting stable ligand binding.  Targeted Hydrophobic Environment: The PHE247 and VAL248 residues create a "hydrophobic nest" ideally suited for anchoring the β-ionone rings of astaxanthin. The measured interatomic distances (3.8–4.2 Å) fall within the optimal range for van der Waals interactions, significantly contributing to the stability of the complex. These in silico findings are consistent with experimental studies showing that astaxanthin effectively inhibits NF-κB activation and downstream inflammatory signaling by stabilizing interactions within key regulatory sites of the protein [25, 26].  Molecular docking and network pharmacology approaches have further confirmed the strong binding affinity of astaxanthin for NF-κB and related inflammatory targets, supporting its potential as a chemopreventive and anti-inflammatory agent [41, 42]. 

Dynamics of Hydrogen Bonding

The analysis of polar interactions reveals two critical hydrogen bonds that contribute significantly to the stability and specificity of astaxanthin binding within the C4 pocket of NF-κB. ASN335 (2.9 Å): This hydrogen bond exhibits a donor-acceptor angle of 150–160°, which is close to the theoretical ideal of 180°, indicating maximal bonding strength and optimal geometric alignment. LYS336 (3.1 Å):   This   interaction   further   stabilizes  the hydroxyl groups of astaxanthin, reinforcing the overall ligand-protein complex. Each hydrogen bond is estimated to contribute approximately –1.5 kcal/mol to the total binding energy, representing nearly 40% of the overall binding affinity. This substantial energetic input underscores the importance of specific polar interactions in the high-affinity and selective inhibition of NF-κB by astaxanthin (Figure 4).

Figure 4: Hydrogen Bonding Network Between Astaxanthin and Binding Site Residues

These findings are consistent with the unique molecular features of astaxanthin, such as its hydroxyl and keto groups, which are known to facilitate strong hydrogen bonding and contribute to its potent antioxidant and anti-inflammatory properties [41, 43]. By stabilizing key residues within the NF-κB binding pocket, astaxanthin effectively modulates inflammatory signaling pathways, supporting its therapeutic potential in inflammation-related disorders [41]. 

A particularly notable finding involves the atypical π-σ orbital interaction between the β-ionone ring of astaxanthin and the PHE347 residue of NF-κB: Partial overlap of the π orbitals (astaxanthin’s conjugated double bonds) and σ orbitals (PHE347 side chain) generates additional stabilization energy estimated at –1.2 kcal/mol. This non-covalent interaction arises from the unique electronic configuration of astaxanthin’s polyene backbone and the aromatic system of phenylalanine. Such interactions are rarely observed in protein-ligand complexes and may explain astaxanthin’s unique specificity for NF-κB compared to other carotenoids (e.g., β-carotene or lutein). The spatial alignment required for π-σ overlap likely imposes strict geometric constraints that favor astaxanthin’s rigid, planar structure over more flexible analogues. This interaction, combined with the hydrophobic anchoring and hydrogen bonding described earlier, contributes to a binding mode that sterically blocks NF-κB’s DNA-binding domain. Experimental studies have shown that astaxanthin suppresses NF-κB nuclear translocation and downstream pro-inflammatory cytokine production (e.g., TNF-α, IL-6) in models of oxidative stress, consistent with the in-silico prediction of high-affinity binding to the p50/p65 subunit [44]. 

COX-2 Inhibition by Astaxanthin

Characterization of Binding Sites: CB-Dock analysis identified five potential interaction sites on COX-2, with the three most prominent sites summarized in table 2. The C1 pocket exhibited the highest binding affinity (-10.4 kcal/mol), surpassing the reference inhibitor celecoxib (-9.1 kcal/mol) (figure 5).  Its large volume (4893 ų) accommodates astaxanthin’s extended polyene backbone, similar to its interaction with stromelysin-1’s S1 pocket. Hydrophobic residues (PHE154, HIS117) dominate the binding interface, with hydrogen bonds stabilizing the β-ionone rings. The compact C4 pocket (736 ų) engages astaxanthin via π-σ interactions with PHE86, analogous to its interaction with human COX-2 His386/Asn382.  This site’s geometry favors rigid ligands like astaxanthin over flexible analogues (e.g., β-carotene), explaining its selectivity. Astaxanthin’s dual binding to C1 (catalytic site) and C4 (allosteric site) suggests a multi-mechanistic inhibition profile, comparable to bisdemethoxycurcumin’s dual NF-κB/COX-2 targeting. The large C1 pocket may enable broader anti-inflammatory effects by blocking both substrate entry (arachidonic acid) and prostaglandin release, as observed in rotenone-induced inflammation models. Astaxanthin’s extended conformation spans the COX-2 catalytic cleft, sterically hindering arachidonic acid access while stabilizing the inactive enzyme conformation. This dual action-competitive inhibition (C1) and allosteric modulation (C4)-could explain its superior efficacy over single-target NSAIDs in preclinical models.

Molecular Interactions

Dominant Hydrophobic Interactions Residues: PHE154, PHE86, and PHE88 form a hydrophobic network with astaxanthin’s polyene backbone. Distances: 3.7–4.2 Å, optimal for van der Waals interactions.  Energetic Contribution: ~62% of the total binding energy (−6.5 kcal/mol), highlighting their critical role in stabilizing the complex. Crucial Hydrogen Bond Residue: HIS117 forms a hydrogen bond with the terminal keto group of astaxanthin. Geometry: Bond distance = 2.8 Å; donor-acceptor angle = 158° (near the ideal 180°). This interaction anchors the polar end of astaxanthin, preventing displacement during catalytic activity.  Unique Ph-Sigma (π-σ) Interaction Residue: ALA87 interacts with the β-ionone ring of astaxanthin via partial orbital overlap. Distance: 4.3 Å, within the range for non-covalent stabilization. Rare in protein-ligand complexes, this interaction enhances molecular specificity, differentiating astaxanthin from structurally similar carotenoids like β-carotene.

Pharmacokinetic Properties of Astaxanthin

The intestinal absorption rate of 74.6% listed in the table 3 appears optimistic compared to literature findings [45]. Multiple studies indicate significantly lower bioavailability, with research showing that only approximately 10% of orally ingested astaxanthin is actually absorbed by the body, while 90% passes through the intestinal tract. Other sources place oral bioavailability in the range of 10-50% due to astaxanthin's poor water solubility and limited absorption by intestinal epithelial cells [46,47]. While the table indicates low BBB penetration (0.392), more recent research suggests astaxanthin can indeed cross the blood-brain barrier, as demonstrated by Grimmig et al. [48]. This ability to reach brain tissue contributes to its neuroprotective properties and potential applications in cognitive health.

The "Non" designation for CYP3A4 metabolism aligns with   findings     that     astaxanthin     does     not   undergo autoinduction  of   metabolism   via   CYP3A4   or  CYP2B6.

Table 2: Key parameters of identified binding pockets

Figure 5:  The three-dimensional interactions within the C1 binding site of COX-2

Table 3: Pharmacokinetic Properties of Astaxanthin

Table 4: Comparative Molecular Specificity

However, research shows astaxanthin is metabolized into several compounds including 3-hydroxy-4-oxo-beta-ionol, 3-hydroxy-4-oxo-beta-ionone, and their reduced forms [49].

The two violations noted (MW = 596 g/mol and LogP = 9.696) are consistent with search results showing astaxanthin's molecular weight as 596.84 g/mol [50]. These characteristics contribute to its poor oral bioavailability and have led to research on enhanced delivery systems such as nanoemulsions, liposomes, and lipid-based formulations to improve bioavailability [51, 52]. Studies have shown that lipid-based formulations can significantly enhance astaxanthin bioavailability by up to 3.7-fold compared to standard formulations. After absorption, astaxanthin reaches maximum blood concentration at approximately 2 hours and has an elimination half-life of around 16 hours (15.9±5.3h) [53].  These findings confirm that while astaxanthin has promising biological activities, its pharmacokinetic profile presents challenges for oral administration that require advanced formulation strategies to overcome.

Comparative Molecular Specificity

Comparative analysis against other natural inhibitors (Table 4) reveals astaxanthin's superior binding characteristics and dual-targeting capability. The molecular structure of astaxanthin reveals its extended conjugated polyene chain with terminal ionone rings, which confers optimal spatial configuration for simultaneously engaging both NF-κB and COX-2 binding pockets. This unique structural arrangement enables the formation of critical hydrogen bonds and hydrophobic interactions with key residues in both targets. Astaxanthin's exceptional dual specificity, combined with its superior binding affinity for both inflammatory mediators, positions it as a prime candidate for developing next-generation anti-inflammatory therapeutics with enhanced efficacy and reduced side effects compared to conventional single-target approaches.

This study demonstrates the successful valorization of shrimp processing waste (Aristeus antennatus) from Algerian fisheries into a sustainable source of astaxanthin, leveraging eco-friendly extraction methods with vegetable oils. Sunflower oil emerged as the most effective solvent, yielding 264.96 µg/g astaxanthin under optimized conditions (1:10 solid-liquid ratio, 60°C, 60 minutes). The extracted astaxanthin exhibited significant anti-inflammatory activity in vitro, inhibiting bovine serum albumin denaturation by 64% at 250 µg/mL, with molecular docking revealing dual-target inhibition of NF-κB (−7.9 kcal/mol) and COX-2 (−10.4 kcal/mol). Structural analyses identified key interactions, including hydrophobic anchoring, hydrogen bonding, and π-σ orbital contacts, underpinning its mechanism of action.

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