RESUMEN
The current effort to valorize waste byproducts to increase sustainability and reduce agricultural loss has stimulated interest in potential utilization of waste components as health-promoting supplements. Tomato seeds are often discarded in tomato pomace, a byproduct of tomato processing, yet these seeds are known to contain an array of compounds with biological activity and prebiotic potential. Here, extract from tomato seeds (TSE), acquired from pomace, was evaluated for their ability to effect changes on the gut microbiota using an ex vivo strategy. The results found that TSE significantly increased levels of the beneficial taxa Bifidobacteriaceae in a donor-independent manner, from a range of 18.6-24.0% to 27.0-51.6% relative abundance following treatment, yet the specific strain of Bifidobacteriaceae enhanced was inter-individually variable. These structural changes corresponded with a significant increase in total short-chain fatty acids, specifically acetate and propionate, from an average of 13.3 to 22.8 mmol/L and 4.6 to 7.4 mmol/L, respectively. Together, these results demonstrated that TSE has prebiotic potential by shaping the gut microbiota in a donor-independent manner that may be beneficial to human health. These findings provide a novel application for TSE harvested from tomato pomace and demonstrate the potential to further valorize tomato waste products.
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Microbioma Gastrointestinal , Solanum lycopersicum , Humanos , Extractos Vegetales/química , Semillas/química , Antioxidantes/análisis , Prebióticos/análisisRESUMEN
INTRODUCTION: Intestinal infections are a significant health issue; antibiotics are essential in treating acute intestinal infections. However, evidence in the literature shows that the excessive use of antibiotics has created many threats to human health. This work aimed to study the impact of apple pectin in combination with antibiotics on treating patients with amebiasis and dysentery. METHODOLOGY: Patients suffering from acute intestinal diseases (amebiasis and dysentery) were treated with traditional antibiotic therapy and a new formula containing antibiotics with low and high methoxylated apple pectin in a randomized block design. Four clinical trials were performed at the Infection Disease Hospital from 1998 until 2013. RESULTS: The study demonstrated that the antibiotic-pectin formulae (APF) significantly reduced the severity of acute intestinal infection diseases and allowed patients to recover faster than conventional treatment. APF reduced the patient's stay in the hospital by 3.0 ± 1.0 days. The clinical trial findings demonstrated that applying APF in intestinal infection diseases helped maintain a constant concentration of the antibiotic in the blood and accelerated the clinical recovery of the patients. CONCLUSIONS: It was concluded that using pectin with antibiotics could improve clinical outcomes in patients with acute infectious diseases. Research on elucidating the mechanisms of pectin digestion in the colon, polyphenol content, and its role in dysbiosis recovery, etc., is also considered.
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Amebiasis , Disentería Amebiana , Disentería , Humanos , Antibacterianos/uso terapéutico , Pectinas/uso terapéutico , Disentería/tratamiento farmacológico , Disentería Amebiana/tratamiento farmacológico , Amebiasis/tratamiento farmacológicoRESUMEN
The genus Senna contains globally distributed plant species of which the leaves, roots, and seeds have multiple traditional medicinal and nutritional uses. Notable chemical compounds derived from Senna spp. include sennosides and emodin which have been tested for antimicrobial effects in addition to their known laxative functions. However, studies of the effects of the combined chemical components on intact human gut microbiome communities are lacking. This study evaluated the effects of Juemingzi (Senna sp.) extract on the human gut microbiome using SIFR® (Systemic Intestinal Fermentation Research) technology. After a 48-hour human fecal incubation, we measured total bacterial cell density and fermentation products including pH, gas production and concentrations of short chain fatty acids (SCFAs). The initial and post-incubation microbial community structure and functional potential were characterized using shotgun metagenomic sequencing. Juemingzi (Senna seed) extracts displayed strong, taxon-specific anti-microbial effects as indicated by significant reductions in cell density (40%) and intra-sample community diversity. Members of the Bacteroidota were nearly eliminated over the 48-hour incubation. While generally part of a healthy gut microbiome, specific species of Bacteroides can be pathogenic. The active persistence of the members of the Enterobacteriaceae and selected Actinomycetota despite the reduction in overall cell numbers was demonstrated by increased fermentative outputs including high concentrations of gas and acetate with correspondingly reduced pH. These large-scale shifts in microbial community structure indicate the need for further evaluation of dosages and potential administration with prebiotic or synbiotic supplements. Overall, the very specific effects of these extracts may offer the potential for targeted antimicrobial uses or as a tool in the targeted remodeling of the gut microbiome.
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Antiinfecciosos , Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Microbiota , Humanos , Extracto de Senna/análisis , Extracto de Senna/farmacología , Bacterias , Heces/microbiología , Semillas , Senósidos/análisis , Senósidos/farmacología , Antiinfecciosos/farmacologíaRESUMEN
BACKGROUND & AIMS: Altered plasma acylcarnitine levels are well-known biomarkers for a variety of mitochondrial fatty acid oxidation disorders and can be used as an alternative energy source for the intestinal epithelium when short-chain fatty acids are low. These membrane-permeable fatty acid intermediates are excreted into the gut lumen via bile and are increased in the feces of patients with inflammatory bowel disease (IBD). METHODS: Herein, based on studies in human subjects, animal models, and bacterial cultures, we show a strong positive correlation between fecal carnitine and acylcarnitines and the abundance of Enterobacteriaceae in IBD where they can be consumed by bacteria both in vitro and in vivo. RESULTS: Carnitine metabolism promotes the growth of Escherichia coli via anaerobic respiration dependent on the cai operon, and acetylcarnitine dietary supplementation increases fecal carnitine levels with enhanced intestinal colonization of the enteric pathogen Citrobacter rodentium. CONCLUSIONS: In total, these results indicate that the increased luminal concentrations of carnitine and acylcarnitines in patients with IBD may promote the expansion of pathobionts belonging to the Enterobacteriaceae family, thereby contributing to disease pathogenesis.
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Enterobacteriaceae , Enfermedades Inflamatorias del Intestino , Animales , Humanos , Enterobacteriaceae/metabolismo , Disbiosis , Enfermedades Inflamatorias del Intestino/microbiología , Carnitina/metabolismo , Ácidos Grasos/metabolismo , Escherichia coli , BiomarcadoresRESUMEN
Introduction: In traditional Chinese medicine, the rhizome of Atractylodes macrocephala (Baizhu), the leaves of Isatis indigotica (Daqingye), and the flowers of Albizia julibrissin (Hehuanhua) have been used to treat gastrointestinal illnesses, epidemics, and mental health issues. Modern researchers are now exploring the underlying mechanisms responsible for their efficacy. Previous studies often focused on the impact of purified chemicals or mixed extracts from these plants on cells in tissue culture or in rodent models. Methods: As modulation of the human gut microbiome has been linked to host health status both within the gastrointestinal tract and in distant tissues, the effects of lipid-free ethanol extracts of Baizhu, Daqingye, and Hehuanhua on the human adult gut microbiome were assessed using Systemic Intestinal Fermentation Research (SIFR®) technology (n=6). Results and discussion: Baizhu and Daqingye extracts similarly impacted microbial community structure and function, with the extent of effects being more pronounced for Baizhu. These effects included decreases in the Bacteroidetes phylum and increases in health-related Bifidobacterium spp. and short chain fatty acids which may contribute to Baizhu's efficacy against gastrointestinal ailments. The changes upon Hehuanhua treatment were larger and included increases in multiple bacterial species, including Agathobaculum butyriciproducens, Adlercreutzia equolifaciens, and Gordonibacter pamelaeae, known to produce secondary metabolites beneficial to mental health. In addition, many of the changes induced by Hehuanhua correlated with a rise in Enterobacteriaceae spp., which may make the tested dose of this herb contraindicated for some individuals. Overall, there is some evidence to suggest that the palliative effect of these herbs may be mediated, in part, by their impact on the gut microbiome, but more research is needed to elucidate the exact mechanisms.
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Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Humanos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Medicina Tradicional ChinaRESUMEN
OBJECTIVE: This study evaluated drug delivery systems based on Pectin (P) and Zein (Z) hydrogel microspheres. Piroxicam (Px) loaded P/Z hydrogel microspheres (P/Z HM) were developed, and their extended-release pharmacokinetic properties were evaluated. METHODS: Experiments were executed under three different conditions: in vitro, ex vivo, and in vivo. Then, the in vitro-in vivo correlations (IVIVC) and ex vivo-in vivo correlations (EVIVC) were examined. RESULTS: Analysis of drug release mechanisms were evaluated by fitting the in vitro data into the Ritger- Peppas equation, showing the contribution of both polymers' relaxation and drug diffusion from the hydrogel microspheres. The fraction absorbed in vivo was determined by the deconvolution of plasma concentration data using the Loo-Riegelman method. After oral single-dose administration of the two formulations, their basic independent model parameters were calculated. CONCLUSION: P/Z HM had different drug release behaviors in in vitro and in vivo conditions. However, the ex vivo and in vivo characteristics were similar (R² = 0.99). It seemed reasonable to use the ex vivo method to predict the in vivo drug absorption behavior during the polymeric drug delivery system developmental studies. The P/Z HM formulation maintained the drug dose at the colon site for a long duration and could be applied for delivery of active pharmaceutical and food ingredients to the colon site.
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Piroxicam , Zeína , Preparaciones de Acción Retardada , Hidrogeles , Microesferas , Pectinas , PolímerosRESUMEN
Commercial pectin production is based on vacuum evaporation and alcohol precipitation (VEAP) using large quantities of expensive and flammable alcohol. This process has high production costs that have greatly limited the commercial use of refined pectins. This study demonstrates a new technology using a diaultrafiltration (DUF) process in a pilot plant, which is a low-cost, green, and ecologically friendly way to produce pectin. In terms of the structure and quality of their products, a comparison of the two methods suggest that DUF provides significant (p < 0.05) flux enhancement, high pectin purity, and separation of the main pectin backbones, with higher molar mass (Mw) and less polydispersity (Mw/Mn) of pectin samples. An analysis of the 1D and 2D NMR spectra reveals that the DUF process removes most free impurities extracted along with the pectin macromolecules, making this method preferable to use. An analysis of power and chemical consumption demonstrates that the new process is preferable over existing methods due to lower energy consumption and higher product quality. It also possesses a flexible technical design that allows it to produce semi-products from various raw materials.
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Flores/química , Frutas/química , Tecnología Química Verde , Helianthus/química , Malus/química , Pectinas/aislamiento & purificación , Alcoholes/química , Precipitación Química , Tecnología Química Verde/instrumentación , Estructura Molecular , Peso Molecular , Control de Calidad , Ultrafiltración , Vacio , ResiduosRESUMEN
Apigenin is a flavonoid of low toxicity and multiple beneficial bioactivities. Published reviews all focused on the findings using eukaryotic cells, animal models, or epidemiological studies covering the pharmacokinetics, cancer chemoprevention, and drug interactions of apigenin; however, no review is available on the antimicrobial effects of apigenin. Research proves that dietary apigenin passes through the upper gastrointestinal tract and reaches the colon after consumption. For that reason, it is worthwhile to study the potential interactions between apigenin and human gut microbiota. This review summarizes studies on antimicrobial effects of apigenin as well as what has been reported on apigenin and human gut microbiota. Various levels of effectiveness have been reported on apigenin's antibacterial, antifungal, and antiparasitic capability. It has been shown that apigenin or its glycosides are degraded into smaller metabolites by certain gut bacteria which can regulate the human body after absorption. How apigenin contributes to the structural and functional changes in human gut microbiota as well as the bioactivities of apigenin bacterial metabolites are worth further investigation.
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Antiinfecciosos/uso terapéutico , Apigenina/uso terapéutico , Flavonoides/uso terapéutico , Microbioma Gastrointestinal/efectos de los fármacos , Animales , Antiinfecciosos/farmacocinética , Apigenina/farmacocinética , Bacterias/efectos de los fármacos , Suplementos Dietéticos , Flavonoides/farmacocinética , Humanos , Neoplasias/dietoterapiaRESUMEN
Probiotics have shown beneficial effects on health and prevention of diseases in humans. However, a concern for application of probiotics is the loss of viability during storage and gastrointestinal transit. The aim of this study was to develop an encapsulation system to preserve viability of probiotics when they are administrated orally and apply Lactobacillus rhamnosus GG (LGG) as a probiotic model to evaluate the effectiveness of this approach using in vitro and in vivo experiments. LGG was encapsulated in hydrogel beads prepared using pectin, a food grade polysaccharide, glucose, and calcium chloride, and lyophilized by freeze-drying. Encapsulated LGG was cultured in vitro under the condition that mimicked the physiological environment of the human gastrointestinal tract. Compared to non-encapsulated LGG, encapsulation increased tolerance of LGG in the acid condition, protected LGG from protease digestion, and improved shelf time when stored at the ambient condition, in regard of survivability and production of p40, a known LGG-derived protein involved in LGG's beneficial effects on intestinal homeostasis. To evaluate the effects of encapsulation on p40 production in vivo and prevention of intestinal inflammation by LGG, mice were gavaged with LGG containing beads and treated with dextran sulphate sodium (DSS) to induce intestinal injury and colitis. Compared to non-encapsulated LGG, encapsulated LGG enhanced more p40 production in mice, and exerted higher levels of effects on prevention of DSS-induced colonic injury and colitis and suppression of pro-inflammatory cytokine production. These data indicated that the encapsulation system developed in this study preserves viability of LGG in vitro and in vivo, leading to longer shelf time and enhancing the functions of LGG in the gastrointestinal tract. Thus, this encapsulation approach may have the potential application for improving efficacy of probiotics.
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Glucosa/química , Hidrogeles/administración & dosificación , Lacticaseibacillus rhamnosus , Pectinas/química , Probióticos/administración & dosificación , Administración Oral , Animales , Proteínas Bacterianas/análisis , Cloruro de Calcio/química , Colitis/inducido químicamente , Colitis/metabolismo , Colitis/patología , Colitis/prevención & control , Colon/metabolismo , Colon/patología , Recuento de Colonia Microbiana , Sulfato de Dextran , Heces/química , Hidrogeles/química , Concentración de Iones de Hidrógeno , Lacticaseibacillus rhamnosus/química , Ratones Endogámicos C57BL , Microesferas , Peroxidasa/metabolismo , Probióticos/químicaRESUMEN
Probiotic bacteria can potentially have beneficial effects on the clinical course of several intestinal disorders, but our understanding of probiotic action is limited. We have identified a probiotic bacteria-derived soluble protein, p40, from Lactobacillus rhamnosus GG (LGG), which prevents cytokine-induced apoptosis in intestinal epithelial cells. In the current study, we analyzed the mechanisms by which p40 regulates cellular responses in intestinal epithelial cells and p40's effects on experimental colitis using mouse models. We show that the recombinant p40 protein activated EGFR, leading to Akt activation. Activation of EGFR by p40 was required for inhibition of cytokine-induced apoptosis in intestinal epithelial cells in vitro and ex vivo. Furthermore, we developed a pectin/zein hydrogel bead system to specifically deliver p40 to the mouse colon, which activated EGFR in colon epithelial cells. Administration of p40-containing beads reduced intestinal epithelial apoptosis and disruption of barrier function in the colon epithelium in an EGFR-dependent manner, thereby preventing and treating DSS-induced intestinal injury and acute colitis. Furthermore, p40 activation of EGFR was required for ameliorating colon epithelial cell apoptosis and chronic inflammation in oxazolone-induced colitis. These data define what we believe to be a previously unrecognized mechanism of probiotic-derived soluble proteins in protecting the intestine from injury and inflammation.
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Proteínas Bacterianas/uso terapéutico , Colitis/tratamiento farmacológico , Receptores ErbB/efectos de los fármacos , Lacticaseibacillus rhamnosus/química , Probióticos/química , Administración Rectal , Animales , Apoptosis/efectos de los fármacos , Proteínas Bacterianas/administración & dosificación , Proteínas Bacterianas/aislamiento & purificación , Proteínas Bacterianas/farmacología , Colitis/inducido químicamente , Colitis/enzimología , Colitis/prevención & control , Sulfato de Dextran/toxicidad , Evaluación Preclínica de Medicamentos , Activación Enzimática/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/enzimología , Células Epiteliales/patología , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/fisiología , Hidrogeles , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Lacticaseibacillus rhamnosus/fisiología , Ratones , Ratones Endogámicos C57BL , Microesferas , Oxazolona/toxicidad , Permeabilidad/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinazolinas , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacología , Proteínas Recombinantes/uso terapéutico , Transducción de Señal/efectos de los fármacos , Tirfostinos/farmacologíaRESUMEN
In this study, the ability of pectin-nisin films in combination with ionizing radiation to eliminate Listeria monocytogenes and inhibit its postirradiation proliferation was evaluated. Pectin films containing 0.025% nisin were made by extrusion. The surface of a ready-to-eat turkey meat sample was inoculated with L. monocytogenes at 10(6) CFU/cm2 and covered with a piece of pectin-nisin film. The samples were vacuum packaged and irradiated at 0, 1, and 2 kGy. The treated samples were stored at 10 degrees C and withdrawn at 0, 1, 2, 4, and 8 weeks for microbial analysis. Reductions in L. monocytogenes viability of 1.42, 1.56, 2.85, 3.78, and 5.36 log CFU/cm2 were achieved for the treatments of 1 kGy, pectin-nisin film, 2 kGy, 1 kGy plus pectin-nisin film, and 2 kGy plus pectin-nisin film, respectively. The greatest reduction (5.5 log CFU/cm2) was observed at 1 week for the 2 kGy plus pectin-nisin film treatment, suggesting that nisin was further released from the film to the surface of meat samples. Pectin-nisin films used in this study did not prevent but did significantly slow (P < 0.05) the proliferation of the L. monocytogenes cells that survived irradiation during 8 weeks of storage at 10 degrees C. These data indicate the potential use of pectin-nisin films alone or in combination with ionizing radiation for preventing listeriosis due to postprocessing contamination of ready-to-eat meat products.
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Irradiación de Alimentos , Conservación de Alimentos/métodos , Conservantes de Alimentos/farmacología , Listeria monocytogenes/efectos de la radiación , Productos de la Carne/microbiología , Animales , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Relación Dosis-Respuesta en la Radiación , Embalaje de Alimentos/métodos , Rayos gamma , Humanos , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/crecimiento & desarrollo , Nisina/farmacología , Pectinas/farmacología , Factores de Tiempo , Pavos , VacioRESUMEN
The use of polysaccharides as DNA carriers has high potential for gene therapy applications. Pectin is a structural plant polysaccharide heterogeneous with respect to its chemical structure. It contains branches rich in galactose residues which serve as potential ligands for membrane receptors interaction. In order to make the anionic pectin applicable for DNA complexation, it was modified with three different amine groups (cationic). Pectin-NH2 was prepared by modifying the galacturonic acids carboxyl groups with primary amine groups and further modified to generate pectin-T (T=N+H(CH3)(2)) and pectin-NH2-Q (Q=N+(CH3)(3)). All three modified pectins formed complexes with plasmid DNA as indicated by gel electrophoresis analysis. The size and morphology of pectin-NH2/DNA complexes were examined by transmission electron microscopy (TEM). Transfection experiments were carried out with human embryonic kidney cell lines (HEK293), using plasmid DNA encoding for green fluorescence protein (GFP). Transfection efficiency was analyzed by flow cytometry analysis, using FACS. Pectin-NH2-Q was the most efficient carrier. Addition of chloroquine ("lysosomotropic" agent) to transfection medium substantially enhanced the HEK293 transfection, indicating that endocytosis is the preferable internalization pathway and implies on the complex inability to escape the endosome. Pectin's galactose residues contribution to transfection was examined by inhibiting pectin binding to membrane receptors (galectins), using galactose and lactose as competitive inhibitors to this interaction. Resulting reduction of transfection efficiency demonstrated the importance of pectin's galactose residues to HEK293 transfection. Suggesting the modified pectin is a promising non-viral carrier for targeted gene delivery to cancer cells with galactose-binding lectins on their surface.
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ADN , Portadores de Fármacos/química , Técnicas de Transferencia de Gen , Pectinas/química , Supervivencia Celular , ADN/administración & dosificación , ADN/genética , Electroforesis en Gel de Agar , Endosomas/efectos de los fármacos , Citometría de Flujo , Proteínas Fluorescentes Verdes/genética , Humanos , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Plásmidos , Propiedades de Superficie , TransfecciónRESUMEN
Composite films were prepared from pectin and fish skin gelatin (FSG) or pectin and soybean flour protein (SFP). The inclusion of protein promoted molecular interactions, resulting in a well-organized homogeneous structure, as revealed by scanning electron microscopy and fracture-acoustic emission analysis. The resultant composite films showed an increase in stiffness and strength and a decrease in water solubility and water vapor transmission rate, in comparison with films cast from pectin alone. The composite films inherited the elastic nature of proteins, thus being more flexible than the pure pectin films. Treating the composite films with glutaraldehyde/methanol induced chemical cross-linking with the proteins and reduced the interstitial spaces among the macromolecules and, consequently, improved their mechanical properties and water resistance. Treating the protein-free pectin films with glutaraldehyde/methanol also improved the Young's modulus and tensile strength, but showed little effect on the water resistance, because the treatment caused only dehydration of the pectin films and the dehydration is reversible. The composite films were biodegradable and possessed moderate mechanical properties and a low water vapor transmission rate. Therefore, the films are considered to have potential applications as packaging or coating materials for food or drug industries.
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Peces , Gelatina/química , Pectinas/química , Piel/química , Proteínas de Soja/química , Animales , Fenómenos Químicos , Química Física , Embalaje de Medicamentos/instrumentación , Embalaje de Alimentos/instrumentación , Mecánica , Microscopía Electrónica de RastreoRESUMEN
Novel complex hydrogel beads were prepared from two edible polymers: pectin, a carbohydrate from citrus fruits, and zein, a protein from corn. The pectin/zein complex hydrogels did not swell in physiological environments, but hydrolyzed in the presence of pectinases. An in vitro study showed the capacity of the hydrogels to endure protease attack and residence time variation. The physical and biological properties of the new hydrogels were attributed to molecular entanglement of the two polymers. The pectin networks were stabilized by the bound zein molecules. In turn, the pectin networks shielded the bound zein from protease digestion.
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Colon/fisiología , Sistemas de Liberación de Medicamentos , Excipientes , Pectinas/química , Zeína/química , Antiinflamatorios no Esteroideos/administración & dosificación , Cloruro de Calcio/química , Preparaciones de Acción Retardada , Dextranos/administración & dosificación , Composición de Medicamentos , Hidrogeles , Concentración de Iones de Hidrógeno , Indometacina/administración & dosificación , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Microesferas , Péptido Hidrolasas/química , Albúmina Sérica Bovina/administración & dosificaciónRESUMEN
Sugar beet pulp and poly(lactic acid) (PLA) composites were prepared by compression-heating. The resultant thermoplastics had a lower density, but they had tensile strength similar to that of pure PLA specimens as well as the same geometric properties. Tensile properties depended on the initial water content of sugar beet pulp and the process by which composites were manufactured. In comparison with sugar beet pulp, the composite showed improved water resistance. This can be attributed to the hydrophobic character of PLA and pulp-matrix interactions. The composite thermoplastics showed suitable properties for potential use as lightweight construction materials.
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Beta vulgaris/química , Ácido Láctico/química , Polímeros/química , Fenómenos Químicos , Química Física , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Rastreo , Poliésteres , Resistencia a la Tracción , Agua/análisisRESUMEN
Using citronellal as a model compound, pectin gels formulations were evaluated for the controlled fragrance release by kinetic and static methods. The pectins with higher degrees of esterification induced a stronger molecular association with the nonpolar fragrance. This resulted in a prolonged duration of fragrance release and the limitation of fragrance adsorption to the receptor skin layers. The increase in pectin concentrations suppressed the fragrance release by a diffusion mechanism. Blocking the carboxyl groups of pectin with calcium ions reduces the hydrophilicity of pectin and provides physical barriers for citronellal diffusion. The pectin/calcium microparticles are promising materials for controlled fragrance release.
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Aldehídos/farmacocinética , Preparaciones de Acción Retardada/farmacocinética , Monoterpenos/farmacocinética , Pectinas/química , Perfumes/farmacocinética , Monoterpenos Acíclicos , Adsorción , Aldehídos/química , Preparaciones de Acción Retardada/química , Difusión , Esterificación , Geles , Monoterpenos/química , Perfumes/química , Vehículos Farmacéuticos , Tecnología Farmacéutica/métodos , Viscosidad , VolatilizaciónRESUMEN
Pectins of low and high degrees of esterification, as well as pectin derivatives carrying primary amines, were investigate for gel forming ability with mucosal tissues. The combination of scanning electronic microscopy and small deformation dynamic mechanical studies revealed that pectins with higher net electrical charges are more bioadhesive than the less charged ones. Both the negatively charged pectin formulation, P-25, and the positively charged formulation, P-N, were able to synergize with the mucus to produce rheologically strengthened gels. The highly esterified pectin, P-94, also synergized with the mucosal glycoproteins to form a gel structure via coil entanglements. The ex vivo studies further confirmed the microstructures of mucus gel networks with adsorbed pectins. When incubated with porcine intestinal mucus membrane, P-94 gels were found generally bound to the lumen area, P-25 gels were able to penetrate deeply near the wall area, P-N gels interacted with mucins via electrostatic bonding and dispersed into the whole area from the lumen to the wall. Hence, both P-N and P-94, by enhancing the protective barrier properties of mucus systems, may be useful alternatives for the treatment of mucus related irritation and infection. In drug-delivery systems, P-N and P-25 would deliver incorporated drugs mainly by pectin dissolution, while a diffusion mechanism would release drugs from P-94 gels.
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Materiales Biocompatibles/química , Colon/metabolismo , Pectinas/química , Animales , Colon/efectos de los fármacos , Difusión , Sistemas de Liberación de Medicamentos , Geles , Concentración de Iones de Hidrógeno , Microscopía Confocal , Microscopía Electrónica de Rastreo , Mucinas/química , Pectinas/farmacología , Estructura Terciaria de Proteína , Reología , Porcinos , Termodinámica , Factores de TiempoRESUMEN
The aim of the research was to develop matrices for the delivery of biologically active substances for tissue regeneration. To this end, a new biodegradable matrix composed of a hydrophobic porous poly(lactide-co-glycolide), p(LGA), network entangled with another network of hydrophilic pectin was fabricated in the presence of calcium chloride. The calcium salts function as both a pore forming reagent and cross-linker for the formation of pectin networks; the method combines creating pores and cross-linking polymers in one step. Microscopic imaging and dynamic mechanical analysis revealed a double-network structure of the composite matrices. The pectin enables the composite to carry signal molecules. This is accomplished by linking signal molecules to pectin by physical adsorption or by chemical reaction. The p(LGA) networks in the composite impart mechanical properties comparable to p(LGA) alone. The mechanical properties of the composite are far superior to matrices containing only pectin. Furthermore, the pectin-containing matrices improved cell adhesion and proliferation when compared to plain p(LGA) matrices, as determined in vitro by osteoblast culture.
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Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos/métodos , Ácido Láctico/química , Osteoblastos/citología , Pectinas/química , Ácido Poliglicólico/química , Polímeros/química , Albúmina Sérica Bovina/química , Ingeniería de Tejidos/métodos , Adsorción , Animales , Ingeniería Biomédica/métodos , Adhesión Celular/fisiología , División Celular/fisiología , Línea Celular , Materiales Manufacturados/análisis , Ensayo de Materiales , Ratones , Ratones Endogámicos C57BL , Osteoblastos/fisiología , Tamaño de la Partícula , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Propiedades de Superficie , TemperaturaRESUMEN
Pectin-derived matrices are now being examined and tested for controlled drug delivery. Pectin is intact in the upper gastrointestinal tract and degraded by colonic microflora. The composition of this microflora remains relatively consistent across a diverse human population. Thus, pectin-derived drug carriers provide promising potential for colon-specific drug delivery. This paper reviews recent developments in pectin-derived formulations. Subjects reviewed include gelation of pectin, calcium cross-linked pectinate, composites of pectin and other polymers, technologies to fabricate pectin into useful drug delivery vehicles, and methods to evaluate release kinetics of incorporated drugs. This article discusses advantages, limitations, and possible future developments in pectin-based formulations with particular emphasis on the field of colon-specific drug delivery.