Search Results (1,719)

This study investigated the effects of a novel phytosynbiotic feed supplement derived from double-layer microencapsulated Pediococcus acidilactici V202 and Tiliacora triandra leaf extract (DMP) on the growth performance, nutrient utilization, gut fermentation, intestinal morphology, and cecal microbiota of broiler chickens. A total of 250 one-day-old male Ross 308 broilers were randomly assigned to five dietary treatments: basal control diet, antibiotic growth promoter (AGP) with chlortetracycline at 0.07%, and DMP supplementation at 0.25, 0.50, or 1.00% (w/w) for 42 days. Compared with the control diet, feeding the DMP led to linear or quadratic responses (p < 0.05) on average daily gain, feed efficiency, productive index, and economic returns. Apparent digestibility of dry matter, crude protein, and apparent metabolizable energy was enhanced in DMP-fed broilers, indicating improved nutrient utilization efficiency. These performance responses were accompanied by pronounced alterations in cecal fermentation, characterized by increased lactic acid, total volatile fatty acids, and particularly acetic and butyric acid levels (p < 0.01). Microbiome analysis revealed that the DMP selectively enriched fermentative SCFA-producing bacterial orders, including Lachnospirales, Oscillospirales, and Lactobacillales. It also reduced the relative abundance of less desirable taxa. As evidenced by an increased villus height and surface area in the duodenum and jejunum, along with a higher villus height-to-crypt depth ratio in the ileum, feeding the DMP also enhanced small intestinal morphology. These coordinated morphological adaptations are indicative of enhanced epithelial maturation and reduced crypt hyperplasia, likely mediated by elevated microbial SCFA production in the gut. In conclusion, the DMP improved broiler growth performance by coordinating the modulation of the gut microbiota, SCFA levels, and intestinal morphology, resulting in enhanced nutrient digestibility and productivity. This phytosynbiotic strategy represents a sustainable plant-based alternative to antibiotic growth promoters for environmentally responsible poultry production. Full article

Aquaculture sustainability requires a reduction in the reliance on marine-derived raw materials such as fish oil in aquafeeds while maintaining fish health and product quality. This study investigated the effects of replacing fish oil with plant oils supplemented with DHA-rich Schizochytrium limacinum biomass on the gut microbiota of European sea bass (Dicentrarchus labrax). S. limacinum SR21—an oleaginous microalga naturally rich in omega-3 fatty acids—was produced through heterotrophic fermentation using crude glycerol, a waste stream from biodiesel production, within a circular economy framework. A 21-week feeding trial was conducted in an indoor recirculating aquaculture system using 280 fish distributed across eight tanks. Four experimental diets were tested: fish oil-based (FO), plant oil-based without microalga (VO + 0), and plant oil-based supplemented with 5% (VO + 5) or 10% (VO + 10) microalgal biomass. Gut microbiota was analyzed in 22 fish per group using 16S rRNA gene sequencing. While alpha and beta diversity analyses of gut microbiota revealed modest structural shifts at phylum and class ranks, genus-rank differences were evident, with Lactobacillus and Clostridium sensu stricto associated with FO and VO + 0 diets, and Pseudomonas and Staphylococcus enriched in microalga-supplemented groups. Functional inference highlighted enhanced bile acid biosynthesis and carbohydrate metabolism in VO + 0, whereas antioxidant-related pathways, including ubiquinone and carotenoid biosynthesis, were stimulated in VO + 5 and VO + 10 groups. These results demonstrate that S. limacinum biomass modulates microbiota functional capacity, potentially contributing to oxidative stress mitigation and host resilience. The findings support microbiota-informed feed formulation strategies to advance sustainable aquaculture. Full article

Cenchrus fungigraminus is a high-yielding forage material, but due to its relatively high lignin content and low carbohydrate content, its current feed utilization primarily relies on silage methods. However, current research on C. fungigraminus silage faces challenges such as unclear fermentation strains and low fiber degradation efficiency of traditional commercial starters, which prevent them from meeting the requirements for C. fungigraminus silage production. So, this study aimed to evaluate the fiber degradation effects of Bacillus velezensis JC2 (isolated from C. fungigraminus), the commercial cellulose-degrading bacterium Bacillus velezensis (CBV), and Trichoderma longibrachiatum (CTL) on C. fungigraminus. The degradation performance of JC2 was assessed based on the lignocellulose content of silage samples, scanning electron microscopy observations, crystallinity, and changes in chemical bonds and functional groups. Furthermore, the three strains exhibiting the highest activities of CMCase, FPase, and β-glucosidase during the screening process were combined with enzyme preparations to develop a specialized silage additive suitable for C. fungigraminus. The results indicate that: (1) Compared to commercial cellulose-degrading strains, after 14 days of fermentation with JC2 treatment, the lignin in C. fungigraminus was effectively degraded. (2) The silage feed of C. fungigraminus treated with a mixture of JC2, JC3, and JC28 showed significant improvements in sensory evaluation, lactic acid content, and cellulose degradation rate. The pH value decreased rapidly (<4.2), while the LA content and the LA/AA ratio increased, and the NDF content decreased by 4.2% DM, effectively enhancing the quality of the silage feed. In summary, the Bacillus velezensis JC2 selected in this experiment effectively degraded the fiber structure of C. fungigraminus, improved the quality of the silage, and enhanced its nutritional value, demonstrating significant potential as a specialized silage additive for C. fungigraminus. Full article

The application of Genome-Scale Metabolic Network Models (GSMM) in fermentation optimization is hampered by challenges in differentiating viable from dead cells and parameter distortion induced by conventional detection methods. Using E. coli BL21(DE3) as the model organism, this study developed a flux analysis strategy that couples cell kinetics with GSMM. Key parameters were estimated using the gradient descent algorithm, thereby enabling precise prediction of viable cell concentration and glucose consumption dynamics. Integrating this with the Quadratic Programming-based parsimonious Flux Balance Analysis (QP-pFBA) algorithm, intracellular metabolic reaction fluxes were quantified. Results demonstrated that the model can effectively differentiate viable from dead cells; Batch D, adopting the gradient-increasing feeding strategy, achieved the maximum specific growth rate (μ_max) of 0.6457, the highest among the four batches. Moreover, key metabolic reaction fluxes were highly correlated with the feeding strategy. This framework forgoes specialized, high-cost equipment and offers robust cross-strain/process adaptability, thereby greatly advancing GSMM utility. It provides a powerful tool for precise fermentation control and accelerates the shift toward data-driven biomanufacturing. Full article

Background/Objectives: Although copper nanoparticles (Cu-NPs) are increasingly explored as food and feed additives, there is still limited evidence on how the commonly consumed dietary fibre matrix modulates their effects on the gut microbiota. This study evaluated whether different dietary fibres (cellulose, pectin, inulin, psyllium) modulate Cu-NP–driven changes in caecal microbiota activity, composition, and bile acid metabolism in rats in a multifactorial design accounting for fibre type, copper dose, and copper form. Methods: Wistar male rats (n = 10 per group, 10 groups) were fed semi-purified diets for 6 weeks. Cu-NPs were provided at 6.5 or 13 mg Cu/kg diet and combined with cellulose (control fibre) or with pectin, inulin, or psyllium. Caecal digesta parameters, microbial enzyme activities, short-chain fatty acids (SCFAs), bile acids, and 16S rRNA sequencing were used to assess microbial diversity. Results: Final body weight did not differ among groups, whereas feed intake decreased most consistently with inulin and psyllium. Inulin and psyllium increased caecal digesta and tissue mass, while pectin increased caecal ammonia. Higher Cu-NPs dose reduced several microbial enzyme activities and lowered major SCFAs across most treatments; pectin most strongly preserved/enhanced glycosidase activities and was associated with increased SCFA levels vs. control, with a 32% rise in acetate, a 47% rise in propionate, and a 61% rise in butyrate. Fibre type dominated bile acid outcomes: psyllium reduced total bile acids by 11.8% vs. control, while inulin increased muricholic acids by 216% vs. control. Microbiota alpha and beta diversity separated primarily by fibre type, with distinct clustering particularly in pectin-fed groups. Across comparisons, Mucispirillum was consistently reduced in fibre-supplemented groups vs. cellulose, alongside recurrent changes in selected genera; functional profiling highlighted shared shifts in carbohydrate, fermentation, transport, and stress-response features under Cu-NPs exposure. Conclusions: The gastrointestinal and microbiota responses to Cu-NPs are strongly fibre-dependent; thus, Cu-NP safety and functionality should be evaluated together with the accompanying dietary fibre matrix, not as a standalone exposure. Implications for humans remain indirect and require confirmation in human-relevant models and clinical settings. Full article

Grain byproducts can serve as cost-effective alternatives to corn, but may lead to reduced production performance and increased greenhouse gas emissions. This study aimed to investigate the effects of replacing corn with the grain byproducts (wheat bran, sprayed corn bran) subjected to bacterial-enzymatic fermentation treatment or not in Hu sheep, mainly focusing on production performance, energy-nitrogen metabolism, rumen fermentation and greenhouse gas emissions. A total of fifty-four 6-month-old Hu sheep were divided into three groups, with 6 pens per group and 3 sheep per pen, and then randomly allocated to one of the three dietary groups for 60 days, i.e., a control group (CON), a group (RC) that corn was partially (~42%) replaced with grain byproducts, and a group (BF) that corn was partially replaced by fermented grain byproducts. Compared with the CON group, the RC group showed numerically lower rumen total volatile fatty acid (TVFA) concentration and its propionate proportion, nitrogen retention content (NR; −10.22%) and its retention ratio (NR/NI decreased by 4.27 percentage points, absolute reduction from 24.30% to 20.04%), corresponding to a relative decrease of 17.6%.) as well as a numerically reduced net profit (−2.18%) with a decreased feed price (−¥0.16/kg TMR). Meanwhile, the RC group showed a significant increase in the relative abundance of Methanobrevibacter (p < 0.05), accompanied by numerically higher daily methane emissions (+6.14%) and emission intensity (+4.08%), although these methane-related differences did not reach statistical significance (p > 0.05). Compared to the RC group, the BF group resulted in a numerical increase in feed price (+¥0.03/kg TMR), net profit (+27.93%), TVFA concentration, propionate proportion, NR (+28.17%), NR/NI (an increase of 5.38 percentage points), the relative abundance of Prevotella, Shuttleworthia and Succinivibrio as well as the decrease of fecal nitrogen (FN; −12.29%), daily methane emissions (−8.75%), emission intensity (−5.83%) and the relative abundance of Methanobrevibacter. In summary, replacing dietary corn by 42% with wheat bran and sprayed corn bran numerically reduced formula cost and nitrogen utilization, while increasing methane emissions and methanogens abundance, without significantly affecting growth performance. This combination led to no improvement in economic returns for fattening Hu sheep. Bacterial-enzymatic fermentation treatment of these byproducts could mitigate these drawbacks, being superior energy-nitrogen metabolism and lower greenhouse gas emissions intensity, presenting a potential strategy for cost reduction and efficiency enhancement. Further research with larger sample sizes is warranted to confirm these findings and support broader application. Full article

This study aimed to determine the ileal digestibility of amino acids (AA) in various protein sources for 21-day-old broilers. A total of 448 Ross 308 male broilers were allocated to eight dietary treatments with eight replicates in a randomized complete block design. Experimental diets included one nitrogen-free diet and seven test diets, each containing one of the following feed ingredients—dehulled soybean meal (SBM), fermented SBM (FSBM), rapeseed meal (RM), copra meal (CM), palm kernel meal (PKM), corn distillers dried grains with solubles (DDGS), and fish meal (FM), as the sole source of AA. On day 21, all birds were euthanized and subsequently ileal digesta was collected from the distal two-thirds of the ileum, extending from Meckel’s diverticulum to 1 cm proximal to the ileocecal junction. The ileal digestibility of AA in the FM was the greatest, followed by the SBM. The ileal digestibility for AA in the SBM was greater than that in the RM. The ileal AA digestibility in the RM was greater than or not different from that in the FSBM, except for Val and Pro, and superior to the CM and the PKM. The ileal digestibility of AA in the FSBM was greater than or not different from those in corn DDGS, except for Met and Cys. Corn DDGS exhibited greater or not different ileal digestibility of AA compared to that of the CM and the PKM, except for Val and Asp, and the PKM was the lowest. In conclusion, the ileal digestibility of AA was the greatest in the FM, followed by the SBM, FSBM, the RM, corn DDGS, the CM, and the PKM. Furthermore, the results underscore the necessity for continuous evaluation of ileal AA digestibility in various protein sources. Full article

This study aims to construct a nattokinase (NK) high-yielding strain using the multiple-scale breeding method. First, an NK-producing strain Bacillus subtilis A-1 was isolated from fermented soybean, which produces 254 FU/mL of NK. Subsequently, ARTP mutagenesis was employed to screen high-yield mutants with resistance to rifampicin (i.e., strain R-F7), kanamycin (i.e., strain K-E11), and gentamicin (i.e., strain G-D5), and the resulted strains showed NK activity increases of 113.78%, 76.38%, and 62.99%, respectively. Moreover, a fusion strain C-D7 with resistant to the above three antibiotics (i.e., rifampicin, kanamycin, and gentamicin) was obtained by protoplast fusion, which produced 610 FU/mL of NK and represents a 140.16% higher that of strain A-1. The fermenting property of strain C-D7 was also done in a 5-L bioreactor, and results indicated that strain C-D7 produced 1020 ± 35 FU/mL of NK under a two-stage pH control strategy and a two-step feeding strategy. To elucidate the genetic basis for the high-yield phenotype of C-D7. comparative whole-genome analysis was performed between C-D7 and the parental strain A-1. The results revealed that C-D7 harbors specific mutations across multiple functional categories, primarily in genes related to transcription, translation, global regulation, as well as metabolism and secretion. The biological processes affected by these mutations show a strong correlation with the high-yield trait, suggesting their potential collective role in contributing to the observed increase in nattokinase production. Lastly, ituD and srfAC were knocked out to reduce foam during fermentation, thus reducing the use of antifoaming agents and mitigating the negative effects on cell growth. In a word, a genetically stable, high-yield, and low-foaming Bacillus subtilis strain C-D7-ΔDouble was constructed in this study, which provides a core microbial resource and process foundation for the low-cost industrial production of nattokinase. Full article

Riboflavin (RF; vitamin B₂) is an essential micronutrient with broad applications in the food, feed, pharmaceutical, and cosmetic industries and is increasingly relevant in bioelectrochemical systems and environmental biotechnology. Microbial fermentation has replaced chemical synthesis as the dominant industrial production route due to its superior sustainability and scalability. However, despite substantial progress, RF biosynthesis remains constrained by imbalances in precursor supply, complex redox regulation, and regulatory feedback mechanisms that limit metabolic flux toward guanosine triphosphate and ribulose-5-phosphate. This review provides an updated, integrative analysis of RF biotechnology, encompassing biosynthetic pathways, transcriptional and redox-regulation, strain improvement strategies, and fermentation process optimization. Representative industrial producers—including Bacillus subtilis, Ashbya gossypii, and Candida famata—are critically evaluated for productivity, yield, and metabolic robustness, with reported titers reaching up to 29 g L⁻¹ in engineered systems. Emerging microbial platforms, including lactic acid bacteria, thermotolerant and methylotrophic microorganisms, and electroactive bacteria, are discussed in the context of niche applications such as food biofortification and microbial fuel cells. Special emphasis is placed on oxidative stress as a regulatory signal influencing RF overproduction, metabolic rewiring strategies to alleviate precursor bottlenecks, and the biosynthesis of RF derivatives (FMN, FAD, roseoflavin, and 8-aminoriboflavin). In addition, biosafety, regulatory constraints, concerns about genome stability, and antibiotic-free engineering approaches are examined as critical determinants of future industrial competitiveness. By integrating molecular regulation, metabolic engineering, fermentation design, emerging applications, and regulatory perspectives within a unified framework, this review outlines current bottlenecks and future directions for developing safer, more robust, and economically competitive RF-producing microbial platforms. Full article

In recent years, natural bioactive compounds have been increasingly investigated as functional feed additives to enhance livestock production. The present study aims to provide an update on the potential use of these compounds to enhance animal health and the quality of animal products, while critically assessing their principal limitations and future practical applicability. The review is based on peer-reviewed articles published between 2020 and 2025 and retrieved from the Scopus database, ensuring the inclusion of recent and high-impact scientific contributions. Phytogenic feed additives, including polyphenols, terpenoids, and alkaloids, exert beneficial effects on animal health by modulating oxidative stress and inflammatory pathways. Improvements in milk and meat quality are mainly associated with enhanced antioxidant capacity and lipid stability, rather than with the direct transfer of phytochemicals into animal-derived products. In ruminants, selected bioactive compounds may also contribute to methane mitigation through modulation of rumen fermentation and microbial ecology. However, their efficacy remains highly context-dependent and requires precise characterization of composition, dosage, and species-specific application. Future research should therefore prioritize deeper elucidation of metabolic mechanisms, systemic physiological responses, and productive outcomes to better define the conditions under which these compounds exert consistent and biologically meaningful effects. Full article

Microplastic pollution is increasingly serious worldwide, threatening human and animal health. The cow rumen is a key organ for nutrient digestion and absorption, and its fermentation is closely related to rumen microorganisms. Here, we investigated how polystyrene microplastics (PS-MPs) with varying particle sizes and concentrations affect rumen fermentation and the biodegradability of PS-MPs by rumen fermentation. The results reveal that exposure to PS-MPs lowered gas production and gas concentrations, as well as volatile fatty acid content, and these decreases were positively correlated with PS-MP concentration. However, higher PS-MP concentration and larger particle size increased the activity of carboxymethyl cellulose, β-glucosidase, and xylanase. Furthermore, PS-MP exposure reduced the abundance of certain rumen microorganisms and altered metabolic pathways and metabolites linked to PS-MP biodegradation. It was also found that PS-MP content decreased significantly after 24 h fermentation. Therefore, PS-MPs can inhibit rumen fermentation by affecting the rumen microbiome, and rumen microorganisms and their secreted enzymes can biodegrade PS-MPs to produce styrene and derivatives; such small molecules may further disrupt rumen homeostasis, thereby affecting lactation performance. In addition, rumen microbial degradation of PS-MPs provides a new idea to resolve future microplastic contamination challenges. Full article

Reducing the dependence on traditional protein sources, and decreasing feeding costs and nitrogen emissions, are important tasks in livestock production. A 5 × 5 Latin square nitrogen balance trial (five castrated male pigs) and an animal growth experiment with 120 Landrace × Rongchang pigs were performed and randomly divided into five diets: a normal crude protein level diet (CON); LP diet; diversified LP containing broken rice, rapeseed meal, and DDGS (DLP); DLP + 0.05% cellulase (DLP + CE); and DLP + 20% fermented feed (FDLP). The CON group showed higher nitrogen intake, urinary nitrogen, and total nitrogen excretion than the other four groups (p < 0.05). The fecal nitrogen was decreased with the LP, DLP + CE, and FDLP groups compared to the CON group (p < 0.05). The mRNA expression of jejunal fatty acid transport protein 1 was upregulated in the LP, DLP + CE, and FDLP groups compared to the CON and DLP groups (p < 0.05). The DLP + CE group showed a higher intramuscular fat content in pigs than the CON and DLP groups (p < 0.05). In the LD muscle, the FDLP and DLP + CE groups upregulated fatty acid synthase expression compared to the LP and DLP groups (p < 0.05). Colonic mRNA expression of zonula occludens-1 and claudin-1 was upregulated in the FDLP group compared to the CON and DLP groups (p < 0.05). These results suggest that the supplementation of cellulase and fermented feed in DLP diets improved nitrogen utilization and intestinal health without compromising growth performance or meat quality in Landrace × Rongchang pigs. Full article

Moderately fermentable dietary fiber (with different crude fiber [CF] levels), especially when combined with stimbiotic (STB) supplementation, can enhance intestinal health, nutrient utilization, and overall performance in laying hens, although effects depend on fiber type, level, and diet composition. To investigate this, 1200 Bovans White laying hens (32 weeks old) were assigned to a 2 × 6 factorial experiment with two levels of supplementation (without or with 0.01% STB) and six dietary fiber treatments: Control (commercial diet), Corn–soybean, 75:25 wheat–corn, 50:50 wheat–corn, 25:75 wheat–corn, and Corn–soybean. The study spanned five 28-day periods, evaluating productive performance, egg quality, and intestinal morphology. Dietary fiber levels significantly improved feed intake (p = 0.0029), egg production (p < 0.0001), egg mass (p < 0.0001), feed conversion (p < 0.0001), and intestinal structure (p ≤ 0.05), while STB alone had limited effects. Hens fed 75:25 and 50:50 wheat–corn diets consumed more feed, and the highest egg production and mass were observed in layers receiving Control, 75:25 wheat–corn, and Corn–soybean diets. Egg quality benefited from the fiber–STB interaction, producing heavier eggs with higher yolk pigmentation (p ≤ 0.05), thicker shells (p ≤ 0.05), and specific gravity (p ≤ 0.05). STB supplementation increased jejunal villus width (p = 0.0001) and absorptive area (p = 0.0063), whereas fiber type affected ileal villus width (p = 0.0025) and absorptive area (p = 0.0156). Fiber–STB interaction influences the duodenum villus width (p = 0.0106), crypt depth (p = 0.0011), villus-to-crypt ratio (p = 0.0058), and absorptive area (p = 0.0086), and ileum villus width (p = 0.0011), crypt depth (p = 0.0058), and absorptive area (p = 0.0086). In conclusion, the use of 0.01% STB in diets with high crude fiber levels (25:75 and 75:25 wheat–corn ratios) improves performance, egg quality, and intestinal health in laying hens. Full article

Dromedary camels possess unique anatomical, physiological, and metabolic adaptations that enable survival in arid environments; however, these same adaptations make them highly sensitive to nutritional imbalance under modern feeding conditions. This review synthesizes current knowledge on nutritional pathologies and metabolic disorders in camels, emphasizing the links between diet composition, foregut fermentation, mineral status, and systemic health. Imbalances in energy and carbohydrates predispose camels to subacute and acute acidosis, negative energy balance, and ketosis-like syndromes, particularly when rapidly fermentable feeds are introduced without adequate fiber or water. Protein and nitrogen disorders, including ammonia toxicity and impaired urea recycling, arise from mismatches between degradable protein, fermentable energy, hydration, and mineral availability. Widespread deficiencies of phosphorus, copper, cobalt, zinc, selenium, and vitamins A and E remain major constraints, leading to pica, poor microbial fermentation, oxidative stress, immunosuppression, reproductive failure, and skeletal disorders. Nutritional disturbances frequently extend beyond the gastrointestinal tract, forming a gut–liver–kidney metabolic axis characterized by hepatic dysfunction, renal compromise, and systemic oxidative stress. The review also addresses gastrointestinal impaction, foreign-body ingestion, toxic plant consumption, and feeding on human food waste as emerging nutritional challenges, particularly in peri-urban systems. Advances in diagnostic ultrasonography, feed evaluation techniques, probiotics, mineral–vitamin supplementation, and omics-based approaches are discussed as tools for improving early diagnosis and precision nutrition. Despite growing research interest, the lack of camel-specific feeding standards and reliance on cattle-based recommendations remain critical gaps. This review highlights the need for species-specific nutrient requirement models, sustainable rangeland management, and integrative research to support the health, resilience, and productivity of camels under changing environmental and production systems. Full article

Modulation of the gut microbiota represents a promising approach to counteract diet-induced metabolic alterations, with microalgae emerging as potential interventions. Building on our previous in vivo evidence that dietary supplementation with the marine microalga Tisochrysis lutea F&M-M36 (T. lutea) positively modulates selected metabolic alterations under high-fat feeding, the present study aimed to identify potential associations between these metabolic changes and coordinated modifications of the gut microbiota. Animals were fed normal-fat (NF), high-fat (HF), or HF supplemented with 5% T. lutea (HFTiso) diets for three months. Gut microbial profiles were analyzed by 16S rRNA sequencing and correlated with plasma lipids, glucose, blood pressure, fecal lipid excretion, and adiponectin levels. T. lutea supplementation was associated with significant modulation of selected metabolic parameters and coherent alterations in gut microbial communities. Multivariate analyses revealed treatment-dependent clustering of metabolic profiles, with HFTiso forming an intermediate group between HF and NF diets. Beta-diversity analyses showed marked treatment-specific shifts, while alpha-diversity remained stable. Linear discriminant analysis identified 31 discriminative genera, with the HFTiso group enriched in taxa associated with fermentative metabolism and lipid-related metabolic pathways including Anaerotruncus, Marvinbryantia, and Eubacterium coprostanoligenes, while the HF group was linked to Clostridium sensu stricto 1 and Terrisporobacter. Positive correlations between HFTiso-associated taxa and adiponectin levels were consistent with microbiota-associated metabolic signatures. In parallel, T. lutea supplementation was associated with downregulation of colonic Niemann-Pick C1-like 1 (NPC1L1) mRNA expression, a key mediator of intestinal cholesterol uptake. The bioactivity of T. lutea likely reflects its content of polyunsaturated fatty acids, oleic acid, phytosterols, and fucoxanthin; however, whether these components act synergistically or whether specific bioactive compounds are primarily responsible remains to be clarified. Together, these findings indicate that T. lutea supplementation is associated with coordinated changes in gut microbiota composition and transcriptional modulation of the intestinal cholesterol transporter NPC1L1 in the context of selected early-stage metabolic alterations under high-fat feeding. While direct extrapolation to humans remains limited, these results suggest potential translational relevance of T. lutea as a nutraceutical approach targeting early-stage metabolic dysregulation. Future studies will be required to determine the mechanistic contribution of individual bioactive components and to assess whether microbiota- and gene expression-associated changes play a causal role in mediating the observed metabolic outcomes, thereby informing the rational development of T. lutea-derived interventions. Full article