Interactive effects of dietary quercetin nanoparticles on growth, flesh antioxidant capacity and transcription of cytokines and Aeromonas hydrophila quorum sensing orchestrating genes in Nile tilapia (Oreochromis niloticus)

The combined analysis of transcriptomics and metabolomics reveals the mechanisms by which dietary quercetin regulates growth and immunity in Penaeus vannamei

As a potent antioxidant, the flavonoid compound quercetin (QUE) has been widely used in the farming of aquatic animals. However, there are fewer reports of the beneficial effects, especially in improving immunity of Penaeus vannamei by QUE. The aim of this study was to investigate the effects of dietary QUE on growth, apoptosis, antioxidant and immunity of P. vannamei. It also explored the potential mechanisms of QUE in improving the growth and immunity of P. vannamei. P. vannamei were fed diets with QUE for 60 days. The results revealed that QUE (0.5 or 1.0 g/kg) ameliorated the growth, and the expressions of genes related to apoptosis, antioxidant, and immunity. The differentially expressed genes (DEGs) and differential metabolites (DMs) obtained through transcriptomics and metabolomics, respectively, enriched in pathways related to nutritional metabolism such as lipid metabolism, amino acid metabolism, and carbohydrate metabolism. After QUE addition, especially at 0.5 g/kg, DEGs were enriched into the functions of response to stimulus and antioxidant activity, and the pathways of HIF-1 signaling pathway, C-type lectin receptor signaling pathway, Toll-like receptor signaling pathway, and FoxO signaling pathway. In conclusion, dietary QUE can ameliorate growth, apoptosis, antioxidant and immunity of P. vannamei, the appropriate addition amount was 0.5 g/kg rather than 1.0 g/kg. Regulations of QUE on nutrient metabolism and immune-related pathways, and bioactive metabolites, were important factors for improving the aforementioned abilities in P. vannamei.

Incorporating Lycium barbarum residue in diet boosts survival, growth, and liver health in juvenile grass carp (Ctenopharyngodon idellus)

This research elucidates the potential of Lycium barbarum residue (LBR), a by-product rich in bioactive substances, as a dietary supplement in aquaculture, especially for herbivorous fish like grass carp. In a detailed 120-day feeding trial, the impacts of varying LBR levels on juvenile grass carp were assessed, focusing on growth performance, survival rate, biochemical markers, and liver health. The study identified a 6% inclusion rate of LBR as optimal for enhancing survival and growth while mitigating hepatic lipid accumulation. Composition analysis of this diet revealed high concentrations of polysaccharides and flavonoids. Notably, the intake of LBR was found to enhance the antioxidant and immune-related enzymatic activities in the liver. Furthermore, it contributed to a reduction in hepatic fat deposition by decreasing the levels of triglycerides (TG) and total cholesterol (T-CHO) both in the liver and serum. Transcriptomic analysis of the liver highlighted LBR's substantial influence on lipid metabolism pathways, including the PPAR signaling pathway, primary bile acid biosynthesis, cholesterol metabolism, bile secretion, fat digestion and absorption, fatty acid degradation and fatty acid biosynthesis. Further, the expression level of genes pinpointed significant downregulation of fasn and dgat2, alongside upregulation of genes like pparda, cpt1b, cpt1ab and abca1b, in response to LBR supplementation. Overall, the findings present LBR as a promising enhancer of growth and survival in grass carp, with significant benefits in promoting fat metabolism and liver health, offering valuable insights for aquacultural nutrition strategies.

Nanomaterials Regulate Bacterial Quorum Sensing: Applications, Mechanisms, and Optimization Strategies

Anti-virulence therapy that interferes with bacterial communication, known as "quorum sensing (QS)", is a promising strategy for circumventing bacterial resistance. Using nanomaterials to regulate bacterial QS in anti-virulence therapy has attracted much attention, which is mainly attributed to unique physicochemical properties and excellent designability of nanomaterials. However, bacterial QS is a dynamic and multistep process, and there are significant differences in the specific regulatory mechanisms and related influencing factors of nanomaterials in different steps of the QS process. An in-depth understanding of the specific regulatory mechanisms and related influencing factors of nanomaterials in each step can significantly optimize QS regulatory activity and enhance the development of novel nanomaterials with better comprehensive performance. Therefore, this review focuses on the mechanisms by which nanomaterials regulate bacterial QS in the signal supply (including signal synthesis, secretion, and accumulation) and signal transduction cascade (including signal perception and response) processes. Moreover, based on the two key influencing factors (i.e., the nanomaterial itself and the environment), optimization strategies to enhance the QS regulatory activity are comprehensively summarized. Collectively, applying nanomaterials to regulate bacterial QS is a promising strategy for anti-virulence therapy. This review provides reference and inspiration for further research on the anti-virulence application of nanomaterials.

Future impact of thymoquinone-loaded nanoemulsion in rabbits: prospects for enhancing growth, immunity, antioxidant potential and resistance against Pasteurella multocida

Phytochemical nanoemulsions, such as thymoquinone nanoemulsions (TQN), are regarded as innovative alternatives to antimicrobials that significantly improve the performance, digestion, antioxidant potential and immunity of rabbits. Thus, the potential effects of TQN on growth, digestibility, antioxidant potential, immunity and resistance against Pasteurella multocida (P. multocida) in rabbits were assessed. Herein, 240 rabbits were offered either a basal diet or diets fortified with three TQN-graded concentrations. At 60 days of age, rabbits were challenged with multidrug-resistant (MDR) virulent P. multocida strain. Our outcomes described that dietary inclusion of TQN, especially at higher concentrations, significantly enhanced the growth performance of rabbits, which was supported by increasing the levels of jejunal lipase, amylase and trypsin enzymes. Of note, the levels of muscle and jejunal antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and total antioxidant capacity (T-AOC)], serum immunological markers (IgG, IgG, IgM and total Igs) and blood phagocytic percentage were significantly provoked after TQN fortification; meanwhile, the levels of muscle and jejunal MDA, serum biochemical parameters (total cholesterol, TG and LDL), abdominal fat percentage, breast and thigh cholesterol were significantly decreased following TQN supplementations. Our findings showed that TQN protected rabbits against P. multocida experimental challenge as evidenced by reducing P. multocida counts in rabbits' lungs, downregulating the transcription levels of P. multocida virulence-related genes (ptfA, toxA and nanB) at 48 and 96 h post-infection and ameliorating the expression levels of cytokines-related genes (IL-1β, IL-10, IL-8, IL-6, DEFB1, TNF-α, TLR-4 and TLR-2) at 96 h post-infection. Our findings suggest the utilization of TQN in rabbits' diets due to their stimulating effects on digestibility as well as their growth-promoting, anti-inflammatory, antioxidant, antibacterial, anti-virulence and immunostimulant properties, which enhance the rabbits' P. multocida resistance.

Tackling strong biofilm and multi-virulent vancomycin-resistant Staphylococcus aureus via natural alkaloid-based porous nanoparticles: perspective towards near future eradication

Introduction

As a growing direction, nano-based therapy has become a successful paradigm used to address the phytogenic delivery-related problems in overcoming multivirulent vancomycin-resistant Staphylococcus aureus (VRSA) infection.

Methods

Hence, our aim was to develop and assess a novel nanocarrier system (mesoporous silica nanoparticles, MPS-NPs) for free berberine (Free-BR) as an antimicrobial alkaloid against strong biofilm-producing and multi-virulent VRSA strains using in vitro and in vivo mouse model.

Results and discussion

Our outcomes demonstrated vancomycin resistance in 13.7% of Staphylococcus aureus (S. aureus) strains categorized as VRSA. Notably, strong biofilm formation was observed in 69.2% of VRSA strains that were all positive for icaA gene. All strong biofilm-producing VRSA strains harbored a minimum of two virulence genes comprising clfA and icaA with 44.4% of them possessing all five virulence genes (icaA, tst, clfA, hla, and pvl), and 88.9% being multi-virulent. The study findings affirmed excellent in vitro antimicrobial and antibiofilm properties of BR-loaded MPS-NPs. Real-time quantitative reverse transcription PCR (qRT-PCR) assay displayed the downregulating role of BR-loaded MPS-NPs on strong biofilm-producing and multi-virulent VRSA strains virulence and agr genes in both in vitro and in vivo mice models. Additionally, BR-loaded MPS-NPs supplementation has a promising role in attenuating the upregulated expression of pro-inflammatory cytokines' genes in VRSA-infected mice with attenuation in pro-apoptotic genes expression resulting in reduced VRSA-induced apoptosis. In essence, the current study recommends the future scope of using BR-loaded MPS-NPs as auspicious alternatives for antimicrobials with tremendous antimicrobial, antibiofilm, anti-quorum sensing (QS), and anti-virulence effectiveness against problematic strong biofilm-producing and multi-virulent VRSA-associated infections.

Multidrug resistant and multivirulent avian bacterial pathogens: tackling experimental leg disorders using phytobiotics and antibiotics alone or in combination

Locomotor disorders caused by multidrug-resistant (MDR) bacterial pathogens denote one of the most detrimental issues that collectively threaten the poultry industry leading to pronounced economic losses across the world. Hence, searching for effective alternatives, especially those extracted from plant origins became of great priority targeting a partial or complete replacement of chemical antimicrobials to tackle their developing resistance. Therefore, we aimed to determine the prevalence and antimicrobial resistance of Staphylococcus aureus (S. aureus), Salmonella species, Mycoplasma synoviae (M. synoviae), and Escherichia coli (E. coli) recovered from 500 broilers and ducks (250 each) with locomotor disorders in various farms in Dakahlia and Sharkia Governorates, Egypt. Additionally, we assessed, for the first time, the in vitro antimicrobial effectiveness of marjoram, garlic, ginger and cinnamon essential oils (EOs) against MDR and multivirulent bacterial isolates as well as the in vivo efficiency of the most effective antibiotics and EOs either separately or in combination in the treatment of experimentally induced poultry leg disorders. The overall prevalence rates of S. aureus, E. coli, Salmonella species, and M. synoviae were 54, 48, 36, and 2%, respectively. Salmonella species and S. aureus prevailed among ducks and broilers (36 and 76%, respectively). Notably, MDR was observed in 100, 91.7, 81.1, and 78.5% of M. synoviae, E. coli, Salmonella, and S. aureus isolates, respectively. Our in vitro results displayed that marjoram was the most forceful EO against MDR and multivirulent chicken vancomycin-resistant S. aureus (VRSA) and duck S. Typhimurium isolates. The current in vivo results declared that marjoram in combination with florfenicol or amoxicillin/clavulanic acid succeeded in relieving the induced duck and chicken leg disorders caused by S. Typhimurium and VRSA, respectively. This was evidenced by improvement in the clinical and histopathological pictures with a reduction of bacterial loads in the experimental birds. Our encountered successful in vitro and in vivo synergistic effectiveness of marjoram combined with florfenicol or amoxicillin/clavulanic acid recommends their therapeutic application for leg disorders and offers opportunities for reducing the antibiotics usage in the poultry industry.

The combined effect of a novel formula of herbal extracts on bacterial infection and immune response in Micropterus salmoides

Herbal extracts have been considered as ideal alternative to antibiotics in aquaculture and application of combinatory effective extracts always can exhibit the enhanced bioactivity with high efficiency. In our study, a novel herbal extract combination GF-7, which is composed of Galla Chinensis, Mangosteen Shell extracts as well as the effective parts of Pomegranate peel and Scutellaria baicalensis Georgi extracts, was prepared and applied for the therapy of bacterial infection in aquaculture. The HPLC analysis of GF-7 was also investigated for quality control and chemical identification. In the bioassay, GF-7 had excellent antibacterial activity against various aquatic pathogenic bacteria in vitro, and the related MIC values were between 0.045 and 0.36 mg/mL. After feeding Micropterus salmoide with GF-7 (0.1, 0.3, and 0.6%, respectively) for 28 days, the activities of ACP, AKP, LZM, SOD, and CAT of the liver in each treatment group were significantly increased and the content of MDA was significantly decreased. Meanwhile, the hepatic expression of the immune regulators including IL-1β, TNF-α, and Myd88 at different times was up-regulated in varying degrees. The challenge results exhibited a good dose-dependent protective effect on M. salmoides infected with A. hydrophila, which was further confirmed by liver histopathology. Our results imply that the novel combination GF-7 is a potential natural medicine for the prevention and treatment of numerous aquatic pathogenic infectious diseases in aquaculture.

Curcumin loaded liposome formulation: Enhanced efficacy on performance, flesh quality, immune response with defense against Streptococcus agalactiae in Nile tilapia (Orechromis niloticus)

Application of novel trend comprising antioxidant phytogenics is aiming to minimize the stress related factors and associated diseases in intensive fish culturing. Today, the concept of exploiting and protecting natural antioxidants represents a paradigm shift for the aqua feed industry. Therefore, our principal goal targeting liposome as a novel nanocarrier for curcumin is directed to attain superior performance, fillet antioxidant stability and bacterial resistance in Nile tilapia. A total of 500 Nile tilapia fingerlings (average body weight, 10.27 ± 0.10 g) assigned into five experimental groups in 25 glass aquaria of 120 L capacity at the density 20 fish/aquaria. The experimental groups were supplemented with varying doses of liposomal curcumin-NPs, LipoCur-NPs (0, 5, 15, 25 and 35 mg/kg diet) were reared for 12 weeks and later Streptococcus agalactiae (S. agalactiae) challenged model was performed. Inclusion of LipoCur-NPs (25 and 35 mg/kg diet) had the most prominent impact on Nile tilapia growth rate and feed conversion ratio. The immune boosting outcomes post supplementing 35 mg/kg diet of LipoCur-NPs were evidenced by higher myeloperoxidase, lysozyme and total immunoglobulin levels. Even after 4 weeks frozen storage, LipoCur-NPs at the dose of 35 mg/kg diet prominently increased (P < 0.05) the fillet scavenging capability for free radicals (1,1-diphenyl-2-picrylhydrazyl and 2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) with an inverse reduction in lipid peroxidation biomarker (malondialdehyde). Notably, upregulation of GSH-Px, CAT, and SOD genes in fillet of 35 mg/kg LipoCur-NPs fed fish coordinated with higher T-AOC and lower oxidative markers (ROS and H₂O₂). Post S. agalactiae challenge, higher supplementation levels of LipoCur-NPs (35 mg/kg diet) greatly attenuated the expression of its vital virulence genes (cfb, fbsA and cpsA) with higher expression of Igm, CXC-chemokine and MHC genes. Concordantly, downregulation of inflammatory markers (IL-1β, TNF-α and IL-8) and upregulation of anti-inflammatory ones (IL-10 and TGF-β) were remarkably documented. Based on these findings, the innovative curcumin loaded liposome was considered a novel multitargeting alternative not only playing an imperative role in Nile tilapia growth promotion and fillet stability upon storage, but also protecting efficiently against S. agalactiae.

Novel Antioxidant Insights of Myricetin on the Performance of Broiler Chickens and Alleviating Experimental Infection with Eimeria spp.: Crosstalk between Oxidative Stress and Inflammation

In the modern poultry industry, the application of novel phytogenic bioactive compounds with antioxidant potential aims to enhance productivity and quality and to minimize the stress of associated diseases. Herein, myricetin, a natural flavonoid, was evaluated for the first time on broiler chickens' performance, antioxidants and immune modulating functions, and tackling avian coccidiosis. A total of 500 one-day-old chicks were divided into five groups. The negative (NC) and infected control (IC) groups were fed a control diet without additives, and the latter was infected with Eimeria spp. Groups supplemented with myricetin (Myc) were fed a control diet of Myc (200, 400 and 600 mg/kg diet each). On d 14, all chicks except those in NC were challenged with oocysts of mixed Eimeria spp. Significant improvements in the overall growth rate and feed conversion ratio were detected in the group that was fed 600 mg/kg, unlike the IC group. Notably, groups that were fed 400 and 600 mg/kg showed higher total meat antioxidant capacity with an inverse reduction in oxidative and lipid peroxidation biomarkers (hydrogen peroxide: H₂O₂; reactive oxygen species: ROS; Malondialdehyde: MDA). Of note, the upregulation of glutathione peroxidase; GSH-Px, catalase; CAT, superoxide dismutase; SOD, heme oxygenase-1; HO-1 and NAD(P)H dehydrogenase quinone 1 NQO1 genes in jejunum and muscle were prominently observed with increasing levels of supplemental Myc. At 21 dpi, the severity of coccoidal lesions (p < 0.05) induced by mixed Eimeria spp. and oocyst excretion were greatly reduced in the group that was fed 600 mg/kg of Myc. In the IC group, higher serum levels of C-reactive protein; CRP and nitric oxide; and NO and the upregulated expression of inflammatory biomarkers (interleukin-1β; IL-1β, interleukin-6; IL-6, tumor necrosis factor-α; TNF-α, chemotactic cytokines; CCL20, stromal cell-derived factor-1; CXCL13, and avian defensins; AvBD612) were subsided in higher levels in the Myc-fed groups. Taken together, these findings indicate the promising antioxidant role of Myc in modulating immune responses and reducing growth depression associated with coccidia challenges.

A new pathogenic isolate of Kocuria kristinae identified for the first time in the marine fish Larimichthys crocea

In recent years, new emerging pathogenic microorganisms have frequently appeared in animals, including marine fish, possibly due to climate change, anthropogenic activities, and even cross-species transmission of pathogenic microorganisms among animals or between animals and humans, which poses a serious issue for preventive medicine. In this study, a bacterium was clearly characterized among 64 isolates from the gills of diseased large yellow croaker Larimichthys crocea that were raised in marine aquaculture. This strain was identified as K. kristinae by biochemical tests with a VITEK 2.0 analysis system and 16S rRNA sequencing and named K. kristinae_LC. The potential genes that might encode virulence-factors were widely screened through sequence analysis of the whole genome of K. kristinae_LC. Many genes involved in the two-component system and drug-resistance were also annotated. In addition, 104 unique genes in K. kristinae_LC were identified by pan genome analysis with the genomes of this strain from five different origins (woodpecker, medical resource, environment, and marine sponge reef) and the analysis results demonstrated that their predicted functions might be associated with adaptation to living conditions such as higher salinity, complex marine biomes, and low temperature. A significant difference in genomic organization was found among the K. kristinae strains that might be related to their hosts living in different environments. The animal regression test for this new bacterial isolate was carried out using L. crocea, and the results showed that this bacterium could cause the death of L. crocea and that the fish mortality was dose-dependent within 5 days post infection, indicating the pathogenicity of K. kristinae_LC to marine fish. Since K. kristinae has been reported as a pathogen for humans and bovines, in our study, we revealed a new isolate of K. kristinae_LC from marine fish for the first time, suggesting the potentiality of cross-species transmission among animals or from marine animals to humans, from which we would gain insight to help in future public prevention strategies for new emerging pathogens.

Effect of Quercetin Nanoparticles on Hepatic and Intestinal Enzymes and Stress-Related Genes in Nile Tilapia Fish Exposed to Silver Nanoparticles

Recently, nanotechnology has become an important research field involved in the improvement of animals’ productivity, including aquaculture. In this field, silver nanoparticles (AgNPs) have gained interest as antibacterial, antiviral, and antifungal agents. On the other hand, their extensive use in other fields increased natural water pollution causing hazardous effects on aquatic organisms. Quercetin is a natural polyphenolic compound of many plants and vegetables, and it acts as a potent antioxidant and therapeutic agent in biological systems. The current study investigated the potential mitigative effect of quercetin nanoparticles (QNPs) against AgNPs-induced toxicity in Nile tilapia via investigating liver function markers, hepatic antioxidant status, apoptosis, and bioaccumulation of silver residues in hepatic tissue in addition to the whole-body chemical composition, hormonal assay, intestinal enzymes activity, and gut microbiota. Fish were grouped into: control fish, fish exposed to 1.98 mg L−1 AgNPs, fish that received 400 mg L−1 QNPs, and fish that received QNPs and AgNPs at the same concentrations. All groups were exposed for 60 days. The moisture and ash contents of the AgNP group were significantly higher than those of the other groups. In contrast, the crude lipid and protein decreased in the whole body. AgNPs significantly increased serum levels of ALT, AST, total cholesterol, and triglycerides and decreased glycogen and growth hormone (*** p < 0.001). The liver and intestinal enzymes’ activities were significantly inhibited (*** p < 0.001), while the oxidative damage liver enzymes, intestinal bacterial and Aeromonas counts, and Ag residues in the liver were significantly increased (*** p < 0.001, and * p < 0.05). AgNPs also significantly upregulated the expression of hepatic Hsp70, caspase3, and p53 genes (* p < 0.05). These findings indicate the oxidative and hepatotoxic effects of AgNPs. QNPs enhanced and restored physiological parameters and health status under normal conditions and after exposure to AgNPs.

Quercetin Application for Common Carp (Cyprinus carpio): I. Effects on Growth Performance, Humoral Immunity, Antioxidant Status, Immune-Related Genes, and Resistance against Heat Stress

This study was done to evaluate the effect of different quercetin levels on growth performance, immune responses, antioxidant status, serum biochemical factors, and high-temperature stress responses in common carp (Cyprinus carpio). A total number of 216 common carp with an average weight of 27.21 ± 53 g were divided into 12 tanks (four treatments × three replications) and fed 0 mg/kg quercetin (T0), 200 mg/kg quercetin (T1), 400 mg/kg quercetin (T2), and 600 mg/kg quercetin (T3) for 60 days. There were significant differences in growth performance, and the highest final body weight (FBW), weight gain (WG), specific growth rate (SGR), and feed intake (FI) were observed in T2 and T3 (P < 0.05). Different quercetin levels significantly increased complement pathway activity (ACH50) and lysozyme activity both before and after heat stress (P < 0.05). Catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) were significantly increased in fish exposed to heat stress, but fish fed with a supplemented diet with quercetin showed the lowest levels both before and after heat stress (P < 0.05). Superoxide dismutase (SOD) levels were significantly enhanced in fish fed diets supplemented with quercetin in both phases (P < 0.05). Different quercetin levels led to a significant decrease in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) before and after the challenging test (P < 0.05). Glucose and cortisol levels were significantly higher in the control group compared to the other treatments in both phases (P < 0.05). The expression of glutathione peroxidase (GPx) and lysozyme was markedly upregulated in fish fed with quercetin-supplemented diets (P < 0.05). No marked effects were observed for growth hormone (GR) and interleukin-8 (IL8) (P > 0.05). In conclusion, dietary quercetin supplementations (400-600 mg/kg quercetin) improved growth performance, immunity, and antioxidant status and increased tolerance to heat stress.

Ameliorative Effect of Quercetin against Abamectin-Induced Hemato-Biochemical Alterations and Hepatorenal Oxidative Damage in Nile Tilapia, Oreochromis niloticus

Abamectin (ABM) is a common agricultural pesticide and veterinary anthelmintic drug. It can discharge from the sites of application to aquatic systems via surface run-off or spray drift, causing harmful effects to aquatic organisms. The present study investigated the protective effect of dietary quercetin supplementation on hemato-biochemical parameters and hepato-renal oxidative stress biomarkers in Nile tilapia (Oreochromis niloticus) exposed to a sublethal dose of ABM. Fish were allocated into six equal groups. The first group was kept as a control group. The second and third groups (Q₄₀₀, and Q₈₀₀) were fed diets supplemented with two quercetin levels (400 and 800 mg/kg diet), respectively. The fourth group (ABM) was intoxicated with 20.73 µg/L of ABM. The fifth and sixth groups (ABM + Q₄₀₀, and ABM + Q₈₀₀) were fed diet supplemented with two quercetin levels (400 and 800 mg/kg diet) and simultaneously intoxicated with ABM for 60 days. The results showed that ABM significantly decreased RBCs, hemoglobin content, hematocrit, total protein, albumin levels, and acetylcholinesterase activity activities compared to the control. Meanwhile, ABM significantly increased white blood cells, glucose, total lipids, cholesterol, and alanine and aspartate aminotransferase activities. Liver and kidney levels of lipid peroxidation was significantly increased, while hepato-renal antioxidant biomarkers (reduced glutathione, super oxide dismutase, catalase, and total antioxidant capacity) were significantly decreased upon ABM exposure. On the other hand, quercetin dietary supplementation improved the hemato-biochemical alterations and alleviated oxidative stress induced by ABM exposure. Fish supplemented with quercetin at a level of 800 mg/kg diet showed better alleviating effects against ABM compared to 400 mg/kg diet. Based on these study findings, we suggest that quercetin dietary supplementation (800 mg/kg) offered direct protection against ABM-induced physiological disturbance and oxidative stress in Nile tilapia.

Quercetin-Loaded Mesoporous Silica Nanoparticle-Based Lyophilized Tablets for Enhanced Physicochemical Features and Dissolution Rate: Formulation, Optimization, and In Vitro Evaluation

Mesoporous silica nanoparticles (MSNPs) have been proposed as a potential approach for stabilizing the amorphous state of poorly water-soluble actives. This study aimed to improve the physiochemical characteristics of poorly water-soluble quercetin (QT) through a novel lyophilized formulation. Various parameters, including solvent polarity, QT-carrier mass ratio, and adsorption time, were studied to improve the loading of QT into MSNPs. The optimized loaded MSNPs were formulated into lyophilized tablets through a freeze-drying process using hydrophilic polyvinylpyrrolidone (PVP-K30) as a polymeric stabilizer and water-soluble sucrose as a cryoprotectant. The effect of PVP-K30 and sucrose on the particle size, disintegration time, friability, and time required to release 90% of QT were studied using 3² full factorial design. The optimized formula was characterized using different evaluating techniques; for instance, differential scanning calorimetry, X-ray diffractometry, Fourier transform infrared spectroscopy, drug content, moisture content, and saturation solubility. The analysis proved that QT was consistently kept in the nanosize range with a narrow size distribution. The loaded silica nanoparticles and the optimized formulation are in an amorphous state devoid of any chemical interaction with the silica matrix or the lyophilization excipients. The optimized formula also featured low friability (less than 1%), fast disintegration (< 30 s), and a pronounced enhancement in saturation solubility and dissolution rate. Briefly, we established that the lyophilized MSNPs-based tablet would be a potential strategy for improving the rate of dissolution and, ultimately, the bioavailability of the poorly water-soluble QT.

Exploring the Interactive Effects of Thymol and Thymoquinone: Moving towards an Enhanced Performance, Gross Margin, Immunity and Aeromonas sobria Resistance of Nile Tilapia (Oreochromis niloticus)

Plant-derived bioactive compounds with promising nutritional and therapeutic attributes (phytogenics) are among the top priorities in the aquaculture sector. Therefore, the impact of thymol (Thy) and/or thymoquinone (ThQ) on the growth, immune response antioxidant capacity, and Aeromonas sobria (A. sobria) resistance of Nile tilapia was investigated. Four fish groups were fed a control diet and three basal diets supplemented with 200 mg/kg diet of Thy or ThQ and a blend of both Thy and ThQ at a level of 200 mg/kg diet each. At the end of the feeding trial (12 weeks), the tilapias were challenged intraperitoneally with virulent A. sobria (2.5 × 108 CFU/mL) harboring aerolysin (aero) and hemolysin (hly) genes. The results revealed that tilapias fed diets fortified with a combination of Thy and ThQ displayed significantly enhanced growth rate and feed conversion ratio. Notably, the expression of the genes encoding digestive enzymes (pepsinogen, chymotrypsinogen, α-amylase and lipase) and muscle and intestinal antioxidant enzymes (glutathione peroxidase, catalase and superoxide dismutase) was significantly upregulated in Thy/ThQ-fed fish. An excessive inflammatory response was subsided more prominently in the group administrated Thy/ThQ as supported by the downregulation of il-β, il-6 and il-8 genes and in contrast, the upregulation of the anti-inflammatory il-10 gene. Remarkably, dietary inclusion of Thy/ThQ augmented the expression of autophagy-related genes, whilst it downregulated that of mtor gene improving the autophagy process. Furthermore, Thy/ThQ protective effect against A. sobria was evidenced via downregulating the expression of its aero and hly virulence genes with higher fish survival rates. Overall, the current study encouraged the inclusion of Thy/ThQ in fish diets to boost their growth rates, promote digestive and antioxidant genes expression, improve their immune responses and provide defense against A. sorbia infections with great economic benefits.

Impacts of Fortifying Nile Tilapia (Oreochromis niloticus) Diet with Different Strains of Microalgae on Its Performance, Fillet Quality and Disease Resistance to Aeromonas hydrophila Considering the Interplay between Antioxidant and Inflammatory Response

The oxidative stress facing fish during intensive production brings about diseases and mortalities that negatively influence their performance. Along with that, the increased awareness of omega-3 polyunsaturated fatty acids (omega-3-PUFAs) health benefits has been triggered the introduction of alternative additives in aqua feed that cause not only modulation in fish immune response but also fortification of their fillet. In this context, the role of microalgae mix (NSS) containing Nannochloropsis oculate and Schizochytrium and Spirulina species, which were enriched with bioactive molecules, especially EPA and DHA, was assessed on Nile tilapia's performance, fillet antioxidant stability, immune response, and disease resistance. Varying levels of NSS (0.75, 1.5, and 3%) were added to Nile tilapia's diet for 12 weeks and then a challenge of fish with virulent Aeromonas hydrophila (A. hydrophila) was carried out. Results showed that groups fed NSS, especially at higher levels, showed an improved WG and FCR, which corresponded with enhanced digestive enzymes' activities. Higher T-AOC was detected in muscle tissues of NSS3.0% fed fish with remarkable reduction in ROS, H2O2, and MDA contents, which came in parallel with upregulation of GSH-Px, CAT, and SOD genes. Notably, the contents of EPA and DHA in fillet were significantly increased with increasing the NSS levels. The mean log10 counts of pathogenic Vibrio and Staphylococcus species were reduced, and conversely, the populations of beneficial Lactobacillus and Bacillus species were increased more eminent after supplementation of NSS3.0% and NSS1.5%. Moreover, regulation of the immune response (lysozyme, IgM, ACH50, NO, and MPO), upregulation of IL-10, TGF-β, and IgM, and downregulation of IL-1β, TNF-α, HSP70,and COX-2 were observed following dietary higher NSS levels. After challenge, reduction in A. hydrophila counts was more prominent, especially in NSS3.0% supplemented group. Taken together, the current study encourages the incorporation of such microalgae mix in Nile tilapia's diet for targeting maximum performance, superior fillet quality, and protection against A. hydrophila.

Nigella sativa Extract Potentially Inhibited Methicillin Resistant Staphylococcus aureus Induced Infection in Rabbits: Potential Immunomodulatory and Growth Promoting Properties

Simple Summary

The high incidence of stress-associated diseases post rabbit weaning results in great losses threatening the rabbit industry. The increasing emergence of multidrug resistant (MDR) methicillin-resistant Staphylococcus aureus (MRSA) causes life threatening infections worldwide. Thus, the necessity to look inward for natural alternative treatments is now compelling. In this perspective, Nigella sativa extract (NSE) could serve as an effective antibiotic alternate source against MRSA. Herein, NSE was found to possess iin vitro antimicrobial activities against MRSA clinical isolates. Moreover, the synergistic activity between NSE and other antimicrobials was employed to overcome the MRSA resistance. Our findings added new insights for application of NSE in diets of growing rabbits as a growth promoting and an immunostimulant agent, which in turn reduced the high risk associated MRSA infections in growing rabbits.

Abstract

Weaning is the most crucial period associated with increased stress and susceptibility to diseases in rabbits. Methicillin-resistant Staphylococcus aureus (MRSA), a historic emergent pathogen related to post weaning stressors, adversely affects rabbit’s growth rate and productive cycle. Since MRSA is rapidly evolving antibiotics resistance, natural products are desperately required to tackle the public health threats posed by antimicrobial resistance. Thus, this study aimed to screen the iin vitro antibacterial activity of Nigella sativa extract (NSE) and its interactions with antibiotics against MRSA isolates. Moreover, 200 weaned rabbits were divided into 4 groups to investigate the iin vivo superiority of NSE graded levels towards growth performance, tight junction integrity, immune responsiveness and resistance against MRSA. Herein, NSE showed promising antimicrobial activities against MRSA isolates from animal (77.8%) and human (64.3%) origins. Additionally, MRSA isolates exposed to NSE became sensitive to all antimicrobials to which they were previously resistant. Our results described that the growth-promoting functions of NSE, especially at higher levels, were supported by elevated activities of digestive linked enzymes. Post-NSE feeding, rabbits’ sera mediated bactericidal activities against MRSA. Notably, upregulated expression of occludin, CLDN-1, MUC-2 and JAM-2 genes was noted post NSE supplementation with maximum transcriptional levels in 500 mg/kg NSE fed group. Our data described that NSE constitutively motivated rabbits’ immune responses and protected them against MRSA-induced experimental infection. Our results suggest the antimicrobial, growth stimulating and immunomodulation activities of NSE to maximize the capability of rabbits for disease response.

Chitosan-Ocimum basilicum nanocomposite as a dietary additive in Oreochromis niloticus: Effects on immune-antioxidant response, head kidney gene expression, intestinal architecture, and growth

Several studies have looked into the use of basil, Ocimum basilicum (L.) in aquaculture as a dietary additive; however, more research is needed to see the possibility of it's including in nanocarriers in aquafeeds. An experiment was undertaken to highlight the efficacy chitosan-Ocimum basilicum nanocomposite (COBN), for the first time, on Nile tilapia (Oreochromis niloticus) growth, stress and antioxidant status, immune-related parameters, and gene expression. For 60 days, fish (average weight: 23.55 ± 0.08 g) were fed diets provided with different concentrations of COBN (g/kg): 0 g [COBN0], 1 g [COBN1], 2 g [COBN2], and 3 g [COBN3], where COBN0 was kept as control diet. Following the trial, the fish were challenged with pathogenic bacteria (Aeromonas sobria) and yeast (Candida albicans) infection. In comparison to the control (COBN0), a notable increase in growth parameters (weight gain, feed intake, and specific growth rate) and intestinal morphometric indices (average intestinal goblet cells count, villous width, and length) in all COBN groups was observed, where COBN2 and COBN3 groups had the highest values. The COBN diets significantly (p < 0.05) declined levels of serum triglycerides, glucose, cholesterol, and hepatic malondialdehyde. Moreover, the higher levels of serum biochemical biomarkers (growth hormone, total protein, globulin, and albumin), immunological parameters (phagocytic activity%, nitric oxide, and lysozyme), and hepatic antioxidant parameters (superoxide dismutase, total antioxidant capacity, and glutathione peroxidase) were obvious in the COBN2 and COBN3 groups followed by COBN1. The immune-antioxidant genes (TNF-α, IL-10, IL-1β, TGF-β, GPx, and SOD) were found to be considerably up-regulated in all COBN groups (COBN2 and COBN3 followed by COBN1). Fifteen days post-challenge with A. sobria and C. albicans, the highest survival rate was recorded in the COBN2 group (83.33 and 91.67%) followed by the COBN3 group (75 and 83.33%), respectively. The findings showed that a dietary intervention with COBN can promote growth, intestinal architecture, immunity, and antioxidant markers as well as protect O. niloticus against A. sobria and C. albicans infection. As a result, the COBN at a dose of 2 g/kg could be used as a food additive for the sustainable aquaculture industry.

Impact of Omega-3 Fatty Acids Nano-Formulation on Growth, Antioxidant Potential, Fillet Quality, Immunity, Autophagy-Related Genes and Aeromonas hydrophila Resistance in Nile Tilapia (Oreochromis niloticus)

In modern aquaculture, enriching Nile tilapia’s diet with omega-3 poly-unsaturated fatty acids (PUFAs) not only plays an important role in its general health but also fortifies its fillet with omega-3-PUFAs. However, the major challenge affecting their delivery is their high instability due to oxidative deterioration. Thus, the prospective incorporation of omega-3-PUFAs into nanocarriers can enhance their stability and bioactivity. In this regard, the effect of reformulated omega-3-NPs was investigated on Nile tilapia’s performance, flesh antioxidant stability, immunity, and disease resistance. Four fish groups supplemented with omega-3-PUFAs-loaded nanoparticles (omega-3 NPs) at levels of 0, 1, 2, and 3 g/kg diet and at the end of feeding trial fish challenged with Aeromonas hydrophila. Fish performance (weight gain and feed conversion) was improved in groups supplemented with omega-3-NPs (2 and 3 g/kg diet). The deposition of omega-3-PUFAs in fish flesh elevated with increasing dietary omega-3-NPs. Simultaneously the oxidative markers (H₂O₂, MDA, and reactive oxygen species) in fish flesh were reduced, especially with higher omega-3-NPs. Post-challenge, downregulation of IL-1β, IL-6, IL-8, TNF-α, and caspase-1 were noticed after dietary supplementation of omega-3-NPs. Moreover, mRNA expression of autophagy-related genes was upregulated while the mTOR gene was downregulated with higher omega-3 NPs levels. Lower expression of A. hydrophila ahyI and ahyR genes were detected with omega-3 NPs supplementation. In conclusion, omega-3-NPs application can fortify tilapia flesh with omega-3-PUFAs and augment its performance, immunity, and disease resistance against Aeromonas hydrophila.

Insights into growth-promoting, anti-inflammatory, immunostimulant, and antibacterial activities of Toldin CRD as a novel phytobiotic in broiler chickens experimentally infected with Mycoplasma gallisepticum

Chronic respiratory disease (CRD) caused by Mycoplasma gallisepticum (MG) leads to impaired broiler growth performance and significant economic losses worldwide. The utilization of essential oils (EOs) as natural alternatives to antibiotics to control CRD outbreaks is not completely clarified yet. Thus, we investigated the effect of a commercial EOs mixture (toldin CRD), in comparison to tilmicosin antibiotic, on the clinical observations, growth performance, immunity, digestive enzymes, gut barrier functions, and bacterial loads in broilers experimentally infected with MG. A total of 400 one-day-old broiler chicks were assigned into four groups; negative control (NC), positive control (PC), tilmicosin, and toldin CRD treated groups. All groups except NC were experimentally infected with MG at 14 d of age. Our data showed that birds treated with toldin CRD showed significant enhancement in the body weight gain (BWG) and feed conversion ratio (FCR) (P = 0.001 each) over the whole experimental period. Likely, improved digestibility and intestinal barrier functions in the toldin CRD treated group was evidenced by the significant upregulation (P < 0.05) of cholecystokinin (CCK), alpha 2A amylase (AMY2A), pancreatic lipase (PNLIP), junctional adhesion molecule-2 (JAM-2), occludin, and mucin-2 (MUC-2) genes. Moreover, toldin CRD exhibited immunostimulant and ant-inflammatory activities via significant downregulation (P < 0.05) of tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-6 genes, significant reduction of lysozyme (LYZ), myeloperoxidase (MPO), and nitric oxide (NO) levels (P = 0.03, 0.02, and 0.001, respectively) and significant increase in the immunoglobulin G (IgG) level (P = 0.03). Notably, immunohistochemistry and quantitative real-time polymerase chain reaction (qPCR) results showed prominent reductions (P < 0.05) in the levels of MG antigens and MG loads in the toldin CRD treated group, which were evidenced by relieving the clinical picture of MG experimental infection. In conclusion, we recommend the utilization of toldin CRD as a potential candidate for controlling MG infection in broiler chickens.

Recent Developments and Applications of Nanosystems in the Preservation of Meat and Meat Products

Due to their high water, lipid, and protein content, meat and meat products are highly perishable. The principal spoilage mechanisms involved are protein and lipid oxidation and deterioration caused by microbial growth. Therefore, efforts are ongoing to ensure food safety and increase shelf life. The development of low-cost, innovative, eco-friendly approaches, such as nanotechnology, using non-toxic, inexpensive, FDA-approved ingredients is reducing the incorporation of chemical additives while enhancing effectiveness and functionality. This review focuses on advances in the incorporation of natural additives that increase the shelf life of meat and meat products through the application of nanosystems. The main solvent-free preparation methods are reviewed, including those that involve mixing organic–inorganic or organic–organic compounds with such natural substances as essential oils and plant extracts. The performance of these additives is analyzed in terms of their antioxidant effect when applied directly to meat as edible coatings or marinades, and during manufacturing processes. The review concludes that nanotechnology represents an excellent option for the efficient design of new meat products with enhanced characteristics.

Therapeutic Potential of Quercetin Loaded Nanoparticles: Novel Insights in Alleviating Colitis in an Experimental DSS Induced Colitis Model

Oxidative stress is considered the main etiologic factor involved in inflammatory bowel disease (IBD). Integration of nanocarriers for natural therapeutic agents with antioxidant and anti-inflammatory potential is a novel promising candidate for curing IBD. Herein, the colonic antioxidant and anti-inflammatory effects of different concentrations of quercetin nanoparticles (QT-NPs) were evaluated using a dextran sulfate sodium (DSS)-induced colitis model. Following colitis induction, the efficacy and mechanistic actions of QT-NPs were evaluated by assessing lesion severity, molecular aids controlling oxidative stress and inflammatory response, and histopathological and immunohistochemistry examination of colonic tissues. Administration of QT-NPs, especially at higher concentrations, significantly reduced the disease activity index and values of fecal calprotectin marker compared to the colitic group. Colonic oxidant/antioxidant status (ROS, H₂O₂, MDA, SOD, CAT, GPX and TAC) was restored after treatment with higher concentrations of QT-NPs. Moreover, QT-NPs at levels of 20 mg/kg and, to a lesser extent, 15 mg/kg reduced Nrf2 and HO-1 gene expression, which was in line with decreasing the expression of iNOS and COX2 in colonic tissues. Higher concentrations of QT-NPs greatly downregulated pro-inflammatory cytokines; upregulated genes encoding occludin, MUC-2 and JAM; and restored the healthy architectures of colonic tissues. Taken together, these data suggest that QT-NPs could be a promising alternative to current IBD treatments.

Gut Microbes Reveal Pseudomonas Medicates Ingestion Preference via Protein Utilization and Cellular Homeostasis Under Feed Domestication in Freshwater Drum, Aplodinotus grunniens

With strong demand for aquatic products, as well as a rapid decrease in global fishery resources and capture fisheries, domesticating animals to provide more high-quality proteins is meaningful for humans. Freshwater drum (Aplodinotus grunniens) is widely distributed in the wild habitats of North America. However, the research on A. grunniens and the feed domestication with diets composed of artificial compounds remains unclear. In this study, a 4-month feeding domestication experiment was conducted with A. grunniens larvae to evaluate the underlying mechanism and molecular targets responsible for alternations in the ingestion performance. The results indicated that a significant increase in the final body weight was exhibited by the feed domesticated group (DOM, 114.8 g) when compared to the group that did not ingest the feed (WT, 5.3 g) as the latest version we raised From the result, the final body weight exhibited significant increase between unfavorable with the feed (WT, 5.3 g) and feed domesticated group (DOM, 114.8 g). In addition, the enzyme activity of digestive enzymes like amylase, lipase, and trypsin was increased in DOM. Genes related to appetite and perception, such as NPY4R, PYY, and LEPR, were activated in DOM. 16s rRNA gene sequencing analysis revealed that Pseudomonas sp. increased from 58.74% to 89.77% in DOM, which accounts for the dominant upregulated microbial community at the genus level, followed by Plesiomonas. Analogously, Mycobacterium, Methylocystis, and Romboutsia also accounted for the down-regulated microbes in the diversity. Transcriptome and RT-PCR analysis revealed that feed domestication significantly improved protein digestion and absorption, inhibited apoptosis by AGE-RAGE signaling, and activated extracellular matrix remodeling by relaxin signaling. Integrated analysis of the microbiome and host transcriptome revealed that Pseudomonas-mediated ingestion capacity, protein utilization, and cellular homeostasis might be the underlying mechanism under feed domestication. These results indicate Pseudomonas and its key genes relating to food ingestion and digestion could serve as the molecular targets for feed domestication and sustainable development in A. grunniens.

Nano-silica and magnetized-silica mitigated lead toxicity: Their efficacy on bioaccumulation risk, performance, and apoptotic targeted genes in Nile tilapia (Oreochromis niloticus)

Contamination of aquatic systems with heavy metals (HM) is of great concern owing to their deleterious impact on living organism. The current research is focused on application of silica particles with new functionalized properties (magnetic silica; SiMag or Nanoporous silica; SiNPs) and their efficacy to mitigate lead (pb) toxicity in Nile tilapia. One thousand fingerlings were distributed: two control groups (negative; without pb toxicity (NC) positive (with pb toxicity) and other four groups received two silica sources (SiMag or SiNPs) with two levels (400 and 600 mg/kg diet) for 56 days then exposed to pb for 30 days. Before toxicity exposure, maximum growth, and most improved feed conversion ratio and biochemical parameters were noticed with higher SiMag or SiNPs levels. Serum antioxidant enzymes and their transcriptional levels in muscle and liver were boosted in groups received SiMag or SiNPs. After toxicity exposure, hematological and antioxidants biomarkers maintained at adequate levels in SiMag or SiNPs. Prominent reduction of residual pb in gills, liver, kidney, and muscle was observed in SiNPs then SiMag groups. Interestingly, the maximum down-regulation of P450, caspase-3 and HSP-70 and MT were observed in groups received 600 mg/kg diet of SiMag or SiNPs. The higher level of P53 in liver and gills was detected in PC, inversely reduced in SiMag or SiNPs. Severity of the histopathological alterations in examined organs greatly reduced in groups received SiMag or SiNPs, unlike it were induced in PC group. In conclusion, higher SiMag or SiNPs levels not only mitigate negatives impact of pb toxicity in fish but also ensure its safety for human consumption.