Assessing high-temperature and pressure extraction of bioactive water-soluble polysaccharides from passion fruit mesocarp.

The mesocarp (albedo) of passion fruit is considered a waste product but rich in soluble fibers, especially pectins. Biological activity and health benefits of pectins have recently emerged, especially in colorectal cancer and attenuating inflammation. Pectin conventional extraction often uses mineral acids, which can be hazardous to the environment, and alternatives can be costly. Here, we assessed a high-temperature and pressure method to extract pectin from the passion fruit albedo and evaluated the differences from the water-soluble fractions extracted. HPSEC, HPAEC, FTIR-ATR, and HSQC-NMR were performed to identify and confirm the highly methylated homogalacturonan structures. The heat-modified samples showed a decreased molecular size compared to the untreated sample. Colorectal cancer cell lines showed reduced viability after being treated with different doses of modified samples, with two of them, LW-MP3 and 4, showing the most potent effects. All samples were detected inside cells by immunofluorescence assay. It was observed that LW-MP3 and 4 upregulated the p53 protein, indicating cell-cycle arrest and the cleaved caspase-9 in one of the cell lines, with LW-MP4 enhancing cell death by apoptosis. Since the modified samples were composed of hydrolyzed homogalacturonans, those probably were the responsible structures for these anti-cancer effects.

Antibacterial and Anti-Inflammatory Polysaccharide from Fructus Ligustri Lucidi Incorporated in PVA/Pectin Hydrogels Accelerate Wound Healing.

In cutaneous wound healing, an overproduction of inflammatory chemokines and bacterial infections impedes the process. Hydrogels can maintain a physiologically moist microenvironment, absorb chemokines, prevent bacterial infection, inhibit bacterial reproduction, and facilitate wound healing at a wound site. The development of hydrogels provides a novel treatment strategy for the entire wound repair process. Here, a series of Fructus Ligustri Lucidi polysaccharide extracts loaded with polyvinyl alcohol (PVA) and pectin hydrogels were successfully fabricated through the freeze-thaw method. A hydrogel containing a 1% mixing weight ratio of FLL-E (named PVA-P-FLL-E1) demonstrated excellent physicochemical properties such as swellability, water retention, degradability, porosity, 00drug release, transparency, and adhesive strength. Notably, this hydrogel exhibited minimal cytotoxicity. Moreover, the crosslinked hydrogel, PVA-P-FLL-E1, displayed multifunctional attributes, including significant antibacterial properties, earlier re-epithelialization, production of few inflammatory cells, the formation of collagen fibers, deposition of collagen I, and faster remodeling of the ECM. Consequently, the PVA-P-FLL-E1 hydrogel stands out as a promising wound dressing due to its superior formulation and enhanced healing effects in wound care.

Vitexin-rhamnoside encapsulated with zein-pectin nanoparticles relieved high-fat diet induced lipid metabolism disorders in mice by altering the gut microbiota.

This study aimed to investigate the modulatory effects of Vitexin-rhamnoside (VR) and Zein-VR-pectin nanoparticles (VRN) on lipid metabolism disorders induced by high-fat diet (HFD). The ingestion of VR or VRN attenuated dyslipidemia and fat accumulation in HFD mice, and improved intestinal dysbiosis by regulating the relative abundance of dominant bacteria, alleviating chronic inflammation and hepatic injury in HFD mice. The intervention effect of VRN was significantly higher than that of VR. After fecal microbiota transplantation (FMT) treatment, the fecal microbiota of VRN-treated donor mice significantly attenuated the symptoms associated with hyperlipidemia, confirming that VRN ameliorates HFD-induced disorders of lipid metabolism by modulating the gut microbiota, especially increasing the abundance of Rombousia and Faecalibaculum. Overall, VRN can regulate the gut microbiota and thus improve lipid metabolism. The present study provided new evidence that nanoparticles enhance the bioavailability of food bioactive ingredients.

Phosphorus deficiency-induced cell wall pectin demethylesterification enhances cadmium accumulation in roots of Salix caprea.

Regions affected by heavy metal contamination frequently encounter phosphorus (P) deficiency. Numerous studies highlight crucial role of P in facilitating cadmium (Cd) accumulation in woody plants. However, the regulatory mechanism by which P affects Cd accumulation in roots remains ambiguous. This study aims to investigate the effects of phosphorus (P) deficiency on Cd accumulation, Cd subcellular distribution, and cell wall components in the roots of Salix caprea under Cd stress. The results revealed that under P deficiency conditions, there was a 35.4% elevation in Cd content in roots, coupled with a 60.1% reduction in Cd content in shoots, compared to the P sufficiency conditions. Under deficient P conditions, the predominant response of roots to Cd exposure was the increased sequestration of Cd in root cell walls. The sequestration of Cd in root cell walls increased from 37.1% under sufficient P conditions to 66.7% under P deficiency, with pectin identified as the primary Cd binding site under both P conditions. Among cell wall components, P deficiency led to a significant 31.7% increase in Cd content within pectin compared to P sufficiency conditions, but did not change the pectin content. Notably, P deficiency significantly increased pectin methylesterase (PME) activity by regulating the expression of PME and PMEI genes, leading to a 10.4% reduction in the degree of pectin methylesterification. This may elucidate the absence of significant changes in pectin content under P deficiency conditions and the concurrent increase in Cd accumulation in pectin. Fourier transform infrared spectroscopy (FTIR) results indicated an increase in carboxyl groups in the root cell walls under P deficiency compared to sufficient P treatment. The results provide deep insights into the mechanisms of higher Cd accumulation in root mediated by P deficiency.

Platelet rich fibrin and simvastatin-loaded pectin-based 3D printed-electrospun bilayer scaffold for skin tissue regeneration.

Designing multifunctional wound dressings is a prerequisite to prevent infection and stimulate healing. In this study, a bilayer scaffold (BS) with a top layer (TL) comprising 3D printed pectin/polyacrylic acid/platelet rich fibrin hydrogel (Pec/PAA/PRF) and a bottom nanofibrous layer (NL) containing Pec/PAA/simvastatin (SIM) was produced. The biodegradable and biocompatible polymers Pec and PAA were cross-linked to form hydrogels via Ca2+ activation through galacturonate linkage and chelation, respectively. PRF as an autologous growth factor (GF) source and SIM together augmented angiogenesis and neovascularization. Because of 3D printing, the BS possessed a uniform distribution of PRF in TL and an average fiber diameter of 96.71 ± 18.14 nm was obtained in NL. The Young's modulus of BS was recorded as 6.02 ± 0.31 MPa and its elongation at break was measured as 30.16 ± 2.70 %. The wound dressing gradually released growth factors over 7 days of investigation. Furthermore, the BS significantly outperformed other groups in increasing cell viability and in vivo wound closure rate (95.80 ± 3.47 % after 14 days). Wounds covered with BS healed faster with more collagen deposition and re-epithelialization. The results demonstrate that the BS can be a potential remedy for skin tissue regeneration.

Supplementation of citrus pectin with whole-cell pectinase PG5 on Pichia pastoris promotes recovery of colitis and enhances intestinal barrier function in DSS-treated mice.

A whole-cell biocatalyst was developed by genetically engineering pectinase PG5 onto the cell surface of Pichia pastoris using Gcw12 as the anchoring protein. Whole-cell PG5 eliminated the need for enzyme extraction and purification, while also exhibiting enhanced thermal stability, pH stability, and resistance to proteases in vitro compared to free PG5. Magnetic resonance mass spectrometry analysis revealed that whole-cell PG5 efficiently degraded citrus pectin, resulting in the production of a mixture of pectin oligosaccharides. The primary components of the mixture were trigalacturonic acid, followed by digalacturonic acid and tetragalacturonic acid. Supplementation of citrus pectin with whole-cell PG5 resulted in a more pronounced protective effect compared to free PG5 in alleviating colitis symptoms and promoting the integrity of the colonic epithelial barrier in a mouse model of dextran sulfate sodium-induced colitis. Hence, this study demonstrates the potential of utilizing whole-cell pectinase as an effective biocatalyst to promote intestinal homeostasis in vivo.

Antimicrobial carbon dots/pectin-based hydrogel for promoting healing processes in multidrug-resistant bacteria-infected wounds.

Multidrug-resistant (MDR) bacterial infections have become a significant threat to global healthcare systems. Here, we developed a highly efficient antimicrobial hydrogel using environmentally friendly garlic carbon dots, pectin, and acrylic acid. The hydrogel had a porous three-dimensional network structure, which endowed it with good mechanical properties and compression recovery performance. The hydrogel could adhere closely to skin tissues and had an equilibrium swelling ratio of 6.21, indicating its potential as a wound dressing. In particular, the bactericidal efficacy following 24-h contact against two MDR bacteria could exceed 99.99 %. When the hydrogel was applied to epidermal wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) on mice, a remarkable healing rate of 93.29 % was observed after 10 days. This was better than the effectiveness of the traditionally used antibiotic kanamycin, which resulted in a healing rate of 70.36 %. In vitro cytotoxicity testing and hemolysis assay demonstrated a high biocompatibility. This was further proved by the in vivo assay where no toxic side effects were observed on the heart, liver, spleen, lung, or kidney of mice. This eco-friendly and easy-to-prepare food-inspired hydrogel provides an idea for the rational use of food and food by-products as a wound dressing to control MDR bacterial infections.

Screening and characterization of an anti-inflammatory pectic polysaccharide from Cucurbita moschata Duch.

Pectin polysaccharides have demonstrated diverse biological activities, however, the inflammatory potential of pectin polysaccharides extracted from Cucurbita moschata Duch remains unexplored. This study aims to extract, characterize and evaluate the effects of pumpkin pectin polysaccharide on lipopolysaccharide (LPS)-induced inflammatory response in RAW264.7 cells and dextran sulfate sodium (DSS)-induced colitis in mice, along with its underlying mechanism of action. Initially, we extracted three fractions of pectin polysaccharides from pumpkin and screened them for anti-inflammatory activity in LPS-induced macrophages, identifying CMDP-3a as the most potent anti-inflammatory fraction. Subsequently, CMDP-3a underwent comprehensive characterization through chromatography and spectroscopic analysis, revealing CMDP-3a as an RG-I-HG type pectin polysaccharide with →4)-α-D-GalpA-(1 â†’ and →4)-α-D-GalpA-(1 â†’ 2,4)-α-L-Rhap-(1 â†’ as the main chain. Further, in the LPS-induced RAW264.7 cells model, treatment with CMDP-3a significantly down-regulated the mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines (IL-1ß, TNF-α, and IL-6) by inhibiting the MAPK and NF-κB signaling pathways. Finally, in a mouse colitis model, CMDP-3a administration obviously inhibited DSS-induced pathological alterations and reduced inflammatory cytokine expressions in the colonic tissues by down-regulating the TLR4/NF-κB and MAPK pathways. These findings provide a molecular basis for the potential application of CMDP-3a in reducing inflammatory responses.

Lichen pectin-containing polysaccharide from Xanthoria elegans and its ability to effectively protect LX-2 cells from H2O2-induced oxidative damage.

Xanthoria elegans, a drought-tolerant lichen, is the original plant of the traditional Chinese medicine "Shihua" and effectively treats a variety of liver diseases. However, thus far, the hepatoprotective effects of polysaccharides, the most important chemical constituents of X. elegans, have not been determined. The aim of this study was to screen the polysaccharide fraction for hepatoprotective activity by using free radical scavenging assays and a H2O2-induced Lieming Xu-2 cell (LX-2) oxidative damage model and to elucidate the chemical composition of the bioactive polysaccharide fraction. In the present study, three polysaccharide fractions (XEP-50, XEP-70 and XEP-90) were obtained from X. elegans by hot-water extraction, DEAE-cellulose anion exchange chromatography separation and ethanol gradient precipitation. Among the three polysaccharide fractions, XEP-70 exhibited the best antioxidant activity in free radical scavenging capacity and reducing power assays. Structural studies showed that XEP-70 was a pectin-containing heteropolysaccharide fraction that was composed mainly of (1 â†’ 4)-linked and (1 â†’ 4,6)-linked α-D-Glcp, (1 â†’ 4)-linked α-D-GalpA, (1 â†’ 2)-linked, (1 â†’ 6)-linked and (1 â†’ 2,6)-linked α-D-Manp, and (1 â†’ 6)-linked and (1 â†’ 2,6)-linked ß-D-Galf. Furthermore, XEP-70 exhibited effectively protect LX-2 cells against H2O2-induced oxidative damage by enhancing cellular antioxidant capacity by activating the Nrf2/Keap1/ARE signaling pathway. Thus, XEP-70 has good potential to protect hepatic stellate cells against oxidative damage.

Chitosan/alginate/pectin biopolymer-based Nanoemulsions for improving the shelf life of refrigerated chicken breast.

This study investigated the use of nanoemulsions and various polymer coatings to enhance the quality and shelf life of chicken breast. This comprehensive study explored the antibacterial activity of essential oils (EOs) against Escherichia coli and Staphylococcus aureus, as well as the characterization of nanoemulsions (Nes) and nanoemulsion-based coatings. The antimicrobial potential of EOs, such as cinnamon, tea tree, jojoba, thyme, and black cumin seed oil, was evaluated against microorganisms, and thyme oil exhibited the highest inhibitory effect, followed by cinnamon and tea tree oil by disk diffusion analysis. The MIC and MBC values of EOs were found between 0.16-2.5 mg/mL and 0.16-5 mg/mL, respectively, while thyme EO resulted in the lowest values showing its antimicrobial potential. Then, the essential oil nanoemulsions (EONe) and their coatings, formulated with thyme oil, alginate, chitosan, and pectin, were successfully characterized. Optical microscope observations confirmed the uniform distribution of droplets in all (EONe), while particle size analysis demonstrated multimodal droplet size distributions. The EONe-chitosan coating showed the highest efficacy in reducing cooking loss, while the EONe-chitosan, EONe-alginate, and EONe-pectin coatings displayed promising outcomes in preserving color stability. Microbial analysis revealed the significant inhibitory effects of the EONe-chitosan coating against mesophilic bacteria, psychrophilic bacteria, and yeasts, leading to an extended shelf life of chicken breast. These results suggest the potential application of thyme oil and NE-based coatings in various industries for antimicrobial activity and quality preservation.

Boron-mediated amelioration of copper toxicity in Citrus sinensis seedlings involved reduced concentrations of copper in leaves and roots and their cell walls rather than increased copper fractions in their cell walls.

Little information is available on how boron (B) supplementation affects plant cell wall (CW) remodeling under copper (Cu) excess. 'Xuegan' (Citrus sinensis) seedlings were submitted to 0.5 or 350 µM Cu × 2.5 or 25 µM B for 24 weeks. Thereafter, we determined the concentrations of CW materials (CWMs) and CW components (CWCs), the degree of pectin methylation (DPM), and the pectin methylesterase (PME) activities and PME gene expression levels in leaves and roots, as well as the Cu concentrations in leaves and roots and their CWMs (CWCs). Additionally, we analyzed the Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectra of leaf and root CWMs. Our findings suggested that adding B reduced the impairment of Cu excess to CWs by reducing the Cu concentrations in leaves and roots and their CWMs and maintaining the stability of CWs, thereby improving leaf and root growth. Cu excess increased the Cu fractions in leaf and root pectin by decreasing DPM due to increased PME activities, thereby contributing to citrus Cu tolerance. FTIR and XRD indicated that the functional groups of the CW pectin, hemicellulose, cellulose, and lignin could bind and immobilize Cu, thereby reducing Cu cytotoxicity in leaves and roots.

Transporter targeted-carnitine modified pectin-chitosan nanoparticles for inositol hexaphosphate delivery to the colon: An in silico and in vitro approach.

Orally targeted delivery systems have attracted ample interest in colorectal cancer management. In this investigation, we developed Inositol hexaphosphate (IHP) loaded Tripolyphosphate (Tr) crosslinked Pectin (Pe) Chitosan (Ch) nanoparticles (IHP@Tr*Pe-Ch-NPs) and modified them with l-Carnitine (CE) (CE-IHP@Tr*Pe-Ch-NPs) to improve uptake in colon cells. The formulated CE-IHP@Tr*Pe-Ch-NPs displayed a monodisperse distribution with 219.3 ± 5.5 nm diameter and 30.17 mV surface charge. Cell-line studies revealed that CE-IHP@Tr*Pe-Ch-NPs exhibited excellent biocompatibility in J774.2 and decreased cell viability in DLD-1, HT-29, and MCF7 cell lines. More cell internalization was seen in HT-29 and MCF7 due to overexpression of the OCTN2 and ATB0,+ transporter (CE transporters) compared to DLD-1. The cell cycle profile, reactive oxygen species, apoptosis, and mitochondrial membrane potential assays were performed to explore the chemo-preventive mechanism of CE-IHP@Tr*Pe-Ch-NPs. Moreover, the in-silico docking studies revealed enhanced interactive behavior of CE-IHP@Tr*Pe-Ch-NPs, thereby proving their targeting ability. All the findings suggested that CE-IHP@Tr*Pe-Ch-NPs could be a promising drug delivery approach for colon cancer targeting.

Lactoferrin/pectin nanocomplex encapsulating ciprofloxacin and naringin as a lung targeting antibacterial nanoplatform with oxidative stress alleviating effect.

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium with adaptive metabolic abilities. It can cause hospital-acquired infections with significant mortality rates, particularly in people with already existing medical conditions. Its ability to develop resistance to common antibiotics makes managing this type of infections very challenging. Furthermore, oxidative stress is a common consequence of bacterial infection and antibiotic therapy, due to formation of reactive oxygen species (ROS) during their mode of action. In this study we aimed to alleviate oxidative stress and enhance the antibacterial efficacy of ciprofloxacin (CPR) antibiotic by its co-encapsulation with naringin (NAR) within a polyelectrolyte complex (PEX). The PEX comprised of polycationic lactoferrin (LF) and polyanionic pectin (PEC). CPR/NAR-loaded PEX exhibited spherical shape with particle size of 237 ± 3.5 nm, negatively charged zeta potential (-23 ± 2.2 mV) and EE% of 61.2 ± 4.9 for CPR and 76.2 ± 3.4 % for NAR. The LF/PEC complex showed prolonged sequential release profile of CPR to limit bacterial expansion, followed by slow liberation of NAR, which mitigates excess ROS produced by CPR's mechanism of action without affecting its efficacy. Interestingly, this PEX demonstrated good hemocompatibility with no significant in vivo toxicity regarding hepatic and renal functions. In addition, infected mice administrated this nanoplatform intravenously exhibited significant CFU reduction in the lungs and kidneys, along with reduced immunoreactivity against myeloperoxidase. Moreover, this PEX was found to reduce the lungs´ oxidative stress via increasing both glutathione (GSH) and catalase (CAT) levels while lowering malondialdehyde (MDA). In conclusion, CPR/NAR-loaded PEX can offer a promising targeted lung delivery strategy while enhancing the therapeutic outcomes of CPR with reduced oxidative stress.

Ripe papaya pectins inhibit the proliferation of colon cancer spheroids and the formation of chemically induced aberrant crypts in rats colons.

Pectins are a class of soluble polysaccharides that can have anticancer properties through several mechanisms. This study aimed to characterize the molecular structure of water-soluble fractions (WSF) derived from ripe and unripe papayas and assess their biological effects in two models: the 3D colon cancer spheroids to measure cell viability and cytotoxicity, and the in vivo model to investigate the inhibition of preneoplastic lesions in rats. WSF yield was slightly higher in ripe papaya, and both samples mainly consisted of pectin. Both pectins inhibited the growth of colon cancer HT29 and HCT116 spheroids. Unripe pectin disturbed HT29/NIH3T3 spheroid formation, decreased HCT116 spheroid viability, and increased spheroid cytotoxicity. Ripe pectin had a more substantial effect on the reduction of spheroid viability for HT29 spheroids. Furthermore, in vivo experiments on a rat model revealed a decrease in aberrant crypt foci (ACF) formation for both pectins and increased apoptosis in colonocytes for ripe papaya pectins. The results suggest potential anticancer properties of papaya pectin, with ripe pectin showing a higher potency.

Pectin wrapped halloysite nanotube reinforced Polycaprolactone films for potential wound healing application.

The current research work focuses on preparing the polycaprolactone (PCL) based nanocomposite films embedded with surface modified Halloysite Nanotube (HNT). The avenue of the study is to unravel the applicability of polymer nanocomposites for wound healing. The flexible property of HNT was taken as the major force to accomplish the addition of biopolymer pectin onto its surface. Functionalization of HNT with pectin has certainly enhanced its binding nature with the polymer. The PCL nanocomposite films were characterized by several promising techniques such as FTIR, XRD, DSC-TGA, FESEM, TEM, AFM, and mechanical properties were too examined along. When compared to the plane PCL film, the nanocomposite films manifested favorable results in terms of mechanical and chemical properties. Additionally, biometric studies such as in-vitro swelling, enzymatic degradation, and hemolysis performed on the films gave extremely good results. The haemolytic percentage recorded for the films exhibited a steady decrease with increasing amount of nanofillers. The MTT assay showed cell proliferation and its increase as the embedded HNT is more in the matrix. Wound closure study performed on NIH3T3 cell line with 1, 3 and 5wt% of films has given a strong proof for the involvement of polymer and HNT in the healing procedure.

Oral Administration of Apple Pectin Solution Improves Atopic Dermatitis in a Mouse Model.

The development of atopic dermatitis (AD) involves multiple factors. Three such factors are particularly important in AD onset: immune abnormalities, skin barrier dysfunction, and itching. Many studies report that an imbalance between helper T (Th)1 and Th2 cells causes AD. Apple pectin, a prebiotic, has preventative effects in other allergic diseases (e.g., bronchial asthma and AD), but its potential benefits in AD are unclear. In this study, we investigated the effect of oral apple pectin administration on skin inflammation in an AD mouse model and examined changes in T cells involved in AD. To induce AD, a picryl chloride solution was applied to the shaved back skin of male NC/Nga mice. AD mice then received an oral apple pectin solution (0.4% or 4%) for 35 d. Compared with untreated AD mice, mice in both apple pectin-treated groups showed improvement in AD-induced inflammation and skin symptoms. Histological evaluation showed that apple pectin treatment attenuated epidermal thickening and decreased the number of mast cells and CD4+ cells in AD-induced mice. Apple pectin treatment also reduced serum IgE concentration, as well as expression of the inflammation indicator cyclooxygenase-2 and the Th2-related factors thymic stromal lymphopoietin, interleukin-4, and GATA3. Additionally, increased mRNA expression of the genes that encode interferon-γ and T-bet, which are Th1-related factors, and forkhead box protein P3, were observed in the apple pectin-treated groups. Our findings suggest that apple pectin treatment ameliorates AD by increasing regulatory T cells and improving the Th1/Th2 balance in the skin of AD model mice.

Gut microbiota modulation and effects of a diet enriched in apple pomace on inflammation in a DSS-induced colitis mouse model.

Certain types of soluble dietary fibre, such as pectin and pectic oligosaccharides from different sources, have demonstrated protective effects against inflammation in DSS-induced colitis mouse models. In this work, we have evaluated the impact of a diet enriched in apple pomace (AP-diet), an agricultural by-product with a significant content of pectin and that previously demonstrated prebiotic properties in human fecal batch fermentation models, on the gut microbiota composition, intestinal damage and inflammation markers in a DSS-induced colitis model. We found that the apple pomace enriched diet (AP-diet), providing a significant amount of pectin with demonstrated prebiotic properties, was associated with a slower increase in the disease activity index, translating into better clinical symptomatology of the animals. Histological damage scoring confirmed less severe damage in those animals receiving an AP-diet before and during the DSS administration period. Some serum inflammatory markers, such as TNFα, also demonstrated lower levels in the group receiving the AP-diet, compared to the control diet. AP-diet administration is also associated with the modulation of key taxa in the colonic microbiota of animals, such as some Lachnospiraceae genera and Ruminococcus species, including commensal short chain fatty acid producers that could play a role in attenuating inflammation at the intestinal level.

Exploring the potential of jujube seed powder in polysaccharide based functional film: Characterization, properties and application in fruit preservation.

In this study, we fabricated a novel biodegradable functional film using natural polysaccharides by adding jujube seed powder as an active ingredient. Scanning electron microscopy analysis showed agglomerate formation in the film with increasing concentration of seed powder. Fourier transform-infrared spectroscopy study demonstrated an electrostatic interaction between pectin and chitosan. The water solubility and swelling degree significantly decreased from 55.5 to 47.7 % and 66.0 to 41.9 %, respectively, depicting the film's water resistance properties. Higher opacity and lower transmittance value of the film indicated its protective effect towards light-induced oxidation of food. It was observed that the fabricated active film biodegraded to 82.33 % in 6 days. The DPPH radical scavenging activity of 98.02 % was observed for the functional film. The film showed antifungal activity against B. cinerea and P. chrysogenum. The highest zone of inhibition was obtained against food spoiling bacteria B. subtilis followed by S. aureus, P. aeruginosa and E. coli. Genotoxicity studies with the fabricated film showed a mitotic index of 8 % compared to 3 % in the control film. We used the fabricated film to preserve grapefruits, and the result showed that it could preserve grapes for ten days with an increase in antioxidant activity and polyphenolic content.

Structural characterization, antioxidant and antibacterial activity of three pectin polysaccharides from blueberry.

In this study, three pectin polysaccharides BP1, BP2 and BP3, were purified from blueberries. The weight-average molecular weight (Mw) of BP1, BP2, and BP3 were detected to be 9.027 × 104, 9.313 × 104, and 1.223 × 106 Da, respectively. The structures of the three pectin polysaccharides were characterized and compared based on the results of molecular weight, monosaccharide composition, GC-MS and NMR analysis. Structural characterization revealed that BP1, BP2, and BP3 all contain homogalacturonan (HG) and rhamnogalacturonan I (RG-I) domains, and the rhamnose residues in RG-I domains are substituted at C-4 with side chains such as araban and galactosan. BP2 had the highest degree of esterification and HG domain ratio, followed by BP3 and BP1. In addition, BP1, BP2 and BP3 showed great antioxidant and antibacterial activities, and could destroy the cell membrane of Staphylococcus aureus and Escherichia coli. Moreover, the better DPPH and ABTS free radical scavenging and antibacterial activities of BP1 and BP2 than BP3 might be related to their lower molecular weight. The results of this study will provide essential information for the structure-activity relationship of pectin polysaccharides and research basis for development and application of blueberry pectin polysaccharides.

Doxycycline-Loaded Calcium Phosphate Nanoparticles with a Pectin Coat Can Ameliorate Lipopolysaccharide-Induced Neuroinflammation Via Enhancing AMPK.

Neuroinflammation occurs in response to different injurious triggers to limit their hazardous effects. However, failure to stop this process can end in multiple neurological diseases. Doxycycline (DX) is a tetracycline, with potential antioxidant and anti-inflammatory properties. The current study tested the effects of free DX, DX-loaded calcium phosphate (DX@CaP), and pectin-coated DX@CaP (Pec/DX@CaP) nanoparticles on the lipopolysaccharide (LPS)-induced neuroinflammation in mice and to identify the role of adenosine monophosphate-activated protein kinase (AMPK) in this effect. The present study was conducted on 48 mice, divided into 6 groups, eight mice each. Group 1 (normal control), Group 2 (blank nanoparticles-treated), Group 3 (LPS (untreated)), Groups 4, 5, and 6 received LPS, then Group 4 received free DX, Group 5 received DX-loaded calcium phosphate nanoparticles (DX@CaP), and Group 6 received DX-loaded calcium phosphate nanoparticles with a pectin coat (Pec/DX@CaP). At the end of the experimentation period, behavioral tests were carried out. Then, mice were sacrificed, and brain tissue was extracted and used for histological examination, and assessment of interleukin-6 positive cells in different brain areas, in addition to biochemical measurement of SOD activity, TLR-4, AMPK and Nrf2. LPS can induce prominent neuroinflammation. Treatment with (Pec/DX@CaP) can reverse most behavioral, histopathological, and biochemical changes caused by LPS. The findings of the current study suggest that (Pec/DX@CaP) exerts a significant reverse of LPS-induced neuroinflammation by enhancing SOD activity, AMPK, and Nrf2 expression, in addition to suppression of TLR-4.