GEO-PGS composite shows synergistic and complementary effect on Escherichia coli and improvement of intestinal dysfunction

Effects of dietary supplementation by modified palygorskite and essential oil/palygorskite complex on growth performance and intestinal flora composition of broilers with diarrhea

With the development trend of the industry, it can be seen that the substitution of antibiotics and reduction of zinc oxiden is still the hot spot of the industry. Diarrhea and inflammation occur frequently during livestock and poultry production, which is difficult to control. This experiment aimed to explore the effects and mechanisms of dietary supplementation of modified palygorskite (Mpal) and essential oil/ palygorskite composite (EO-PGS) on disease resistance and intestinal inflammatory damage in diarrhea broiler. In this experiment, there were a total of 420 broilers of 10-day-old selected and divided into 7 groups (n = 60), which were the nondiarrhea group fed with basal diet (normal control, NC), the diarrhea group fed with basal diet (diarrhea control, DC), and the rest were the diarrhea test group (diarrhea), supplemented with 1 kg/t, 2 kg/t and 4 kg/t of essential oils/ palygorskite complex (EO-PGS 1kg/T, EO-PGS 2kg/T, EO-PGS 4kg/T) in the basal diet, respectively, and 2 kg/t, 4 kg/t modified palygorskite group (Mpal 2kg/T, Mpal 4kg/T) in the basal diets, respectively. The experiment lasted for 8 d. The results showed that compared to normal broilers, the diarrhea index of diarrhea broilers remained around 2.0 with persistent mild diarrhea during the test period. The duodenal epithelial cells were damaged and shed, goblet cells increased, inflammatory cells infiltrated, diffuse congestion and hemorrhage in lamina propria, the serum lipopolysaccharides (LPS) content, and malondialdehyde (MDA) content increased significantly (P < 0.05). The serum superoxide dismutase (SOD) activity and immunoglobulin-M (IgM) levels significantly decreased, while serum immunoglobulin-G (IgG) and complement 3 (C3) levels significantly increased (P < 0.05). The expression of inflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and nuclear factor κB (NF-κB) in duodenal epithelial cells was significantly upregulated on d 5 (P < 0.05). The abundance of Bacteroides in the duodenum of diarrhea broilers was significantly decreased, while the abundance of Proteobacteria was significantly increased (P < 0.05). Feeding diets supplemented with EO-PSG and 4 kg/t Mpal increased the average weight of diarrhea broilers (P < 0.05), reduced diarrhea index, improved immunity by increasing serum IgG, IgM, C3 and complement 4 (C4) levels (P < 0.05), enhanced the activity of serum antioxidant enzyme glutathione peroxidase (GSH-PX) and SOD activity, reduced serum MDA content, serum LPS levels, and decreased the expression of proinflammatory factors in the duodenal epithelial cell on d 5 (P < 0.05), alleviated duodenal epithelial cell injury, hemorrhage, inflammation infiltration and intestinal injury of diarrhea broilers from d 5 to d 8. Meanwhile, supplemented with EO-PSG and Mpal in diets regulated the intestinal microbiota, significantly increased the abundance of Bacteroidetes and decreased the abundance of Proteobacteria at the phylum level (P < 0.05). Microbial richness and diversity of microbiota were significantly increased by feeding the diet supplemented with 2 kg/t EO-PGS. In the beta diversity of the intestinal flora of the diets supplemented with 4 kg/t Mpal and 2 kg/t EO-PGS, the microbial community composition could be relatively easily distinguished with NC and DC groups. As a result of LEfSe analysis, the diets supplemented with 2 kg/t EO-PGS f_Clostridiaceae and g_Coprococcus were enriched in the caecum of diarrhea broilers, and the diets supplemented with 4 kg/t Mpal o_Bacteroidales, f_Rikenllaceae and g_Peptococcus were enriched in caecum of diarrhea broilers, between normal and diarrhea broilers (P<0.05). In conclusion, dietary supplementation with EO-PGS and Mpal could improve disease resistance and alleviate intestinal inflammatory damage in diarrhea broilers, but the effect of 2 kg/t Mpal was not significant. It was recommended that 2 kg/t EO-PGS or 4 kg/t Mpal be added to the broilers' diet according to the degree of diarrhea, and continuous feeding for more than 5 d.

Preparation and characterization of high-methoxyl pectin/glycerides emulsion for pH-responsive, targeting, and sustained release of fat-soluble substances

In this study, a pH-responsive emulsion system was prepared, combining high-methoxyl pectin (HMP) with camellia oil glycerides (CG). The emulsion was characterized as O/W type, with HMP serving as the wall material and CG as the oil phase. The physicochemical properties, pH responsiveness, digestion stability, and encapsulated delivery capabilities of the HMP-CG emulsion were investigated. The emulsion showed an average droplet size of 480.47 ± 76.19 nm, possessing a negative charge and a pronounced core-shell structure. HMP package CG enhanced hydrophilic ability and enabled targeted release within the small intestine through the structural changes of HMP. The presence of HMP and CG increased droplet dispersion and target digestibility of the emulsion system, leading to sustainable small intestine-specific release. Overall, HMP-CG emulsion system, composed of natural materials, exhibited the ability to achieve targeted and controllable release via pH-responsive mechanisms, offering an alternative for developing gel materials incorporating fat-soluble substances.

Protective Effect of Citrus Medica limonum Essential Oil against Escherichia coli K99-Induced Intestinal Barrier Injury in Mice

Citrus Medica limonum essential oil (LEO) has been reported to have antibacterial and anti-inflammatory activities, but its protective effect in the intestine remains unknown. In this study, we researched the protective effects of LEO in relation to intestinal inflammation induced by E. coli K99. The mice were pretreated with 300, 600, and 1200 mg/kg LEO and then stimulated with E. coli K99. The results showed that E. coli K99 caused immune organ responses, intestinal tissue injury, and inflammation. LEO pretreatment dose-dependently alleviated these changes by maintaining a low index in the thymus and spleen and producing a high content of immunoglobulin A, G, and M (IgA, IgG, and IgM) and low content of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). Intestinal integrity as a consequence of the LEO pretreatment may be related to the high mRNA expression of intestinal trefoil factor (ITF) and the low mRNA expression of transforming growth factor-β1 (TGF-β1). Conclusively, an LEO pretreatment can alleviate E. coli K99-induced diarrhea, immune organ response, and body inflammation in mice by reducing the levels of inflammatory cytokines and improving the levels of immunoglobulin, and the intestinal integrity remained highest when maintaining the high mRNA expression of ITF and keeping the mRNA expression of TGF-β1 low in the intestinal tissue.

Effects of dietary supplementation with different levels of palygorskite-based composite on growth performance, antioxidant capacity, and meat quality of broiler chickens

This study was conducted to investigate the effects of different levels of palygorskite-based composite (PBC) on growth performance, antioxidant status, and meat quality of broilers. A total of 320 one-day-old mixed-sex Ross 308 broiler chicks were allocated to 1 of 5 groups with 8 replicates of 8 birds each, and given a basal diet supplemented with 0, 250, 500, 1,000, and 2,000 mg/kg PBC for a 42-day trial, respectively. PBC quadratically increased feed efficiency during the late and overall experimental periods (P < 0.05). Compared with the control group, 1,000 mg/kg PBC increased feed efficiency during the overall period (P < 0.05). PBC linearly increased serum total superoxide dismutase (T-SOD) activity at 21 d and glutathione peroxidase (GSH-Px) activity at both 21 d and 42 d (P < 0.05). Compared with the control group, PBC supplementation, regardless of its level, increased 21-day serum SOD activity (P < 0.05). The 21-day serum GSH-Px activity was increased by PBC when its level exceeded 250 mg/kg (P < 0.05). PBC linearly increased 42-day total antioxidant capacity (T-AOC) activity, but linearly decreased 42-day malondialdehyde level in liver (P < 0.05). An addition of PBC, irrespective of its level, increased 42-day hepatic T-AOC activity (P < 0.05). PBC quadratically increased 45-min yellowness value and linearly increased 24-h pH value, but quadratically decreased 24-h lightness value and linearly and quadratically reduced 24-h drip loss in breast muscle (P < 0.05). Compared with the control group, the 24-h drip loss of breast muscle was decreased by PBC, regardless of its dosage (P < 0.05). An addition of PBC linearly increased 42-day T-AOC and T-SOD activities of breast muscle (P < 0.05). Compared with the control group, muscle T-SOD activity was increased by PBC, regardless of its administration level (P < 0.05). These results suggested that PBC could improve growth performance, antioxidant capacity, and meat quality of broilers, and its recommended dosage is 1,000 mg/kg.

Fibrous Clays in Dermopharmaceutical and Cosmetic Applications: Traditional and Emerging Perspectives

Functionalization of natural clay minerals for high value-added pharmaceutical and cosmetic applications receives significant research attention worldwide attributable to a rising demand and ongoing search for green, efficient, economically sustainable and ecofriendly geomaterials. Fibrous clays, i.e. palygorskite and sepiolite, are naturally-occurring hydrated magnesium aluminum silicate clay minerals with 2:1 layer-chain microstructure and one-dimensional nanofibrous morphology. Due to their unique structural, textural and compatibility features, over the past decade, fibrous clays and their organic modified derivatives are increasingly used in the dermopharmaceutical and cosmetic fields as excipients, active agents or nanocarriers to develop novel skin delivery systems or to modify drug release profile for enhanced health effects. This comprehensive review presents the up-to-date information on fibrous clays used in topically-applied products for therapeutic and cosmetic purposes with the focus on their performance-related structural characteristics and the underlying mechanisms. The recent advancement of fibrous clay-based skin delivery systems was summarized in wide range of applications including pelotherapy, wound healing, antimicrobial action, coloration and UV protection. An overview of the commonly used topically-applied dosage forms (powders, hydrogels, films, peloids and Pickering emulsion) as well as the toxicological aspects was also included, which might provide guidance to the design and development of fibrous clay-based skin delivery systems.

Fibrous palygorskite clays as versatile nanocarriers for skin delivery of tea tree oils in efficient acne therapy

This paper presents a facile approach to develop palygorskite (Pal), a fibrous clay mineral, as a delivery system of tea tree oil (TTO) for topical acne therapy. The obtained TTO-Pal composite showed an efficient loading of TTO (27.4%) with a selective accumulation of terpine-4-ol and 1,8-cineole (two major antimicrobial TTO constituents), sustained release of TTO at skin physiological conditions (pH5.4, 32 °C) and superior skin sebum (2.2 g/g) absorbability. In vitro toxicological assessments showed that the Pal incorporation strategy significantly reduced the acute contact toxicity of TTO. The antimicrobial results revealed a preferable bacteriostatic effect for the TTO-Pal system towards opportunistic dermal pathogens (Escherichia coli, Staphylococcus aureus and Propionibacterium acnes) over the beneficial bacterium (Staphylococcus epidermis). Moreover, TTO-Pal based formulations exhibited pronounced clinical therapeutic efficacy in treating facial acne by rapidly reducing inflamed lesions, modulating skin sebum overproduction and restoring barrier function. This is the first report of using fibrous clay as a biocompatible nanocarrier system for topical delivery of essential oils in efficient management of facial acne with both in vitro and in vivo evidences, which may open perspectives for fibrous clay-drug delivery system in topical application and expand the high added value development of this mineral resource in the advanced healthcare fields.

Dietary Palygorskite Clay-Adsorbed Nano-ZnO Supplementation Improves the Intestinal Barrier Function of Weanling Pigs

This study aimed to investigate the effects of PNZ on intestinal mucosal barrier function in weaning piglets. A total of 210, 21-day-old piglets with similar body weights (6.30 ± 0.51 kg) were randomly allocated into seven groups: control group (CON), antibiotic group (ANT), ZnO group (ZO), nano-ZnO group (NZO) and low, middle, and high PNZ groups (LPNZ, MPNZ, and HPNZ). The seven groups were, respectively, fed control diets or control diets supplemented with antibiotics; 3,000 mg/kg ZnO; 800 mg/kg nano-ZnO; 700, 1,000, or 1,300 mg/kg PNZ. More integrated intestinal villi were observed in the LPNZ group. In the jejunum of LPNZ group, the crypt depth significantly decreased (P < 0.05), and the ratio of villus height to crypt depth (V/C) significantly increased (P < 0.05). In addition, the villus width and surface area of the ileum were significantly increased in the LPNZ group (P < 0.05). Dietary supplementation with PNZ can significantly increase the number of goblet cells in the mucosa of the jejunum and ileum (P < 0.05), decrease the contents of TNF-α and IL-1β (P < 0.05), and increase the contents of sIgA and IL-4 in the jejunal and ileal mucosa (P < 0.05). Meanwhile, the mRNA expression of MCU2 and ZO1 in PNZ group were significantly increased (P < 0.05), the mRNA expression of TLR4 and MyD88 was downregulated (P < 0.05). With increasing levels of PNZ, decreased proinflammatory cytokines and increased intestinal mucosal barrier function in weaned pigs was observed. In conclusion, supplementation with PNZ could effectively improve the intestinal barrier function of weanling piglets and potentially could replace the use of high doses of ZnO and antibiotics. The appropriate dose of PNZ for supplementation was 700 mg/kg.

Facile Preparation of Organo-Modified ZnO/Attapulgite Nanocomposites Loaded with Monoammonium Glycyrrhizinate via Mechanical Milling and Their Synergistic Antibacterial Effect

In this study, monoammonium glycyrrhizinate (MAG) was introduced into cetyltrimethyl ammonium bromide (CTAB)-modified ZnO/attapulgite (APT) via a mechanical process to form performance-enhanced antibacterial nanocomposites (MAG/C–ZnO/APT). The APT supported ZnO nanocomposite (ZnO/APT) was prepared by a conventional precipitation method, and 20–50 nm of globular ZnO nanoparticles were uniformly decorated on APT nanorods. The FTIR and zeta potential analyses demonstrated that modification by CTAB facilitated the loading of MAG into ZnO/APT by H-bonding and electrostatic interactions. Antibacterial evaluation results indicate that MAG/C–ZnO/APT nanocomposites with CTAB and MAG doses of 2.5% and 0.25%, respectively, exhibited synergistically enhanced inhibitory activities against Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamases Escherichia coli, with minimum inhibitory concentrations of 1, 0.1, 0.25, 5, 0.1, and 2.5 mg/mL, respectively, which are better than those of ZnO/APT, C–ZnO/APT and MAG. Moreover, the nanocomposites had low cytotoxicity on human normal cell line L-O2. Therefore, this study provided a more effective strategy to extend the antibacterial spectrum and strengthen the inhibitory effects of antibiotic-free materials to address increasingly serious situations of microbial infection.

Copper/Zinc-Modified Palygorskite Protects Against Salmonella Typhimurium Infection and Modulates the Intestinal Microbiota in Chickens

Palygorskite (Pal), a clay nanoparticle, has been demonstrated to be a vehicle for drug delivery. Copper has antibacterial properties, and zinc is an essential micronutrient for intestinal health in animals and humans. However, whether copper/zinc-modified Pal (Cu/Zn-Pal) can protect chickens from Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) infection remains unclear. In this study, three complexes (Cu/Zn-Pal-1, Cu/Zn-Pal-2, and Cu/Zn-Pal-3) were prepared, and Cu/Zn-Pal-1 was shown to be the most effective at inhibiting the growth of S. Typhimurium in vitro, whereas natural Pal alone had no inhibitory effect. In vivo, Cu/Zn-Pal-1 reduced S. Typhimurium colonization in the intestine of infected chickens and relieved S. Typhimurium-induced organ and intestinal mucosal barrier damage. Moreover, this reduction in Salmonella load attenuated intestinal inflammation and the oxidative stress response in challenged chickens. Additionally, Cu/Zn-Pal-1 modulated the intestinal microbiota in infected chickens, which was characterized by the reduced abundance of Firmicutes and the increased abundance of Proteobacteria and Bacteroidetes. Our results indicated that the Cu/Zn-Pal-1 complex may be an effective feed supplement for reducing S. Typhimurium colonization of the gut.