Improving curcumin bactericidal potential against multi-drug resistant bacteria via its loading in polydopamine coated zinc-based metal-organic frameworks.

Multi-drug resistant (MDR) bactearial strains have posed serious health issues, thus leading to a significant increase in mortality, morbidity, and the expensive treatment of infections. Metal-organic frameworks (MOFs), comprising metal ions and a variety of organic ligands, have been employed as an effective drug deliveryy vehicle due to their low toxicity, biodegradability, higher structural integrity and diverse surface functionalities. Polydopamine (PDA) is a versatile biocompatible polymer with several interesting properties, including the ability to adhere to biological surfaces. As a result, modifying drug delivery vehicles with PDA has the potential to improve their antimicrobial properties. This work describes the preparation of PDA-coated Zn-MOFs for improving curcumin's antibacterial properties against S. aureus and E. coli. Powder X-ray diffraction (P-XRD), FT-IR, scanning electron microscopy (SEM), and DLS were utilized to characterize PDA-coated Zn-MOFs. The curcumin loading and in vitro release of the prepared MOFs were also examined. Finally, the MOFs were tested for bactericidal ability against E. coli and S. aureus using an anti-bacterial assay and surface morphological analysis. Smaller size MOFs were capable of loading and releasing curcumin. The findings showed that as curcumin was encapsulated into PDA-coated MOFs, its bactericidal potential was significantly enhanced, and the findings were further supported by SEM which indicated the complete morphological distortion of the bacteria after treatment with PDA-Cur-Zn-MOFs. These studies clearly indicate that the PDA-Cur-Zn-MOFs developed in this study are extremely promising for long-term release of drugs to treat a wide range of microbial infections.

Microarray needles comprised of arginine-modified chitosan/PVA hydrogel for enhanced antibacterial and wound healing potential of curcumin.

Wound healing is a multifaceted and complex process that includes inflammation, hemostasis, remodeling, and granulation. Failures in any link may cause the healing process to be delayed. As a result, wound healing has always been a main research focus across the entire medical field, posing significant challenges and financial burdens. Hence, the current investigation focused on the design and development of arginine-modified chitosan/PVA hydrogel-based microneedles (MNs) as a curcumin (CUR) delivery system for improved wound healing and antibacterial activity. The substrate possesses exceptional swelling capabilities that allow tissue fluid from the wound to be absorbed, speeding up wound closure. The antibacterial activity of MNs was investigated against S. aureus and E. coli. The results revealed that the developed CUR-loaded MNs had increased antioxidant activity and sustained drug release behavior. Furthermore, after being loaded in the developed MNs, it revealed improved antibacterial activity of CUR. Wound healing potential was assessed by histopathological analysis and wound closure%. The observed results suggest that the CUR-loaded MNs greatly improved wound healing potential via tissue regeneration and collagen deposition, demonstrating the potential of developed MNs patches to be used as an effective carrier for wound healing in healthcare settings.

Characterization and Antibacterial Evaluation of Biodegradable Mannose-Conjugated Fe-MIL-88NH2 Composites Containing Vancomycin against Methicillin-Resistant Staphylococcus aureus Strains.

The emergence of bacterial resistance has increased the economic burden of infectious diseases dramatically during the previous few decades. Multidrug resistance (MDR) is difficult to cure in both Gram-negative and positive bacteria and is often incurable with traditional and broad-range antibiotics. Therefore, developing techniques to increase the antibacterial activity of therapeutic drugs is essential. Metal-organic frameworks (MOFs) are extremely versatile hybrid materials made of metal ions coupled via organic bridging ligands. They have been widely used as an excellent vehicle for drug delivery due to their low toxicity, biodegradability, and structural stability upon loading and functionalization. The present study focused on the synthesis of mannose (MNS)-coated MOFs with enhanced surface contact with S. aureus cells. The MNS coating on the surface of MOFs enhances their adherence to bacteria by binding to lectins present on the bacterial cell, resulting in improved VCM cellular penetration and activity against resistant bacteria. Various techniques, including atomic force microscopy, DLS, TGA, FT-IR, and DSC, were employed to analyze MNS-coated MOFs. They were also evaluated for their efficacy against resistant S. aureus. The results indicated that when VCM was loaded into MNS-coated MOFs, their bactericidal activity rose dramatically, resulting in the greater suppression of resistant S. aureus. AFM investigation of S. aureus strains demonstrated total morphological distortion after treatment with MNS-coated drug-loaded MOFs. The results of this work suggest that MNS-coated MOFs may be effective for reversing bacterial resistance to VCM and open new pathways for improving antibiotic therapy for diseases associated with MDR.

Investigation of wound healing potential of photo-active curcumin-ZnO-nanoconjugates in excisional wound model.

Wound healing, being a dynamic process consisting of hemostasis, inflammation, proliferation, and remodeling, involves the complicated interplay of various growth mediators and the cells associated repair system. Current wound healing therapies usually fail to completely regain skin integrity and functionality. Traditionally, curcumin is considered a potent natural wound healing agent as it possesses antibacterial, antioxidant, and anti-inflammatory properties. It is also known that zinc oxide (ZnO) nanoparticles (NPs) have photocatalytic properties, including the generation of reactive oxygen species. ZnO nanoaprticles are also Food and Drug Administration (FDA) approved as safe substances. While ZnO oxide requires illumination with ultraviolet light to become photocatalytically active, dye-sensitized ZnO can be activated by illumination with visible light. In the present study, we explored the wound healing potential of ZnO nanoparticles sensitized with curcumin (Cu+ZnO Nps) and illuminated with visible (blue) light generated by an array of high power LEDs. We studied the antibacterial effect of our conjugates by percentage reduction in bacterial growth and biofilm formation. The wound healing potential was analyzed by percentage wound contraction, biochemical parameters, and histopathological analysis of the wounded site. Additionally, angiogenesis and wound associated cytokines was evaluated by immunohistochemistry of CD31 and gene expression analysis of IL-1ß, TNF-α, and MMP-9 after 16 days of post-wound treatment, respectively. Our study suggests that the therapeutic effect of Cu+ZnO NPs with LED illumination increases its wound healing potential by producing an antibacterial and anti-inflammatory effect. Moreover, the treatment strategy of using a nano formulation in combination with LED illumination further increases its efficacy. It was concluded that the anti-inflammatory and bactericidal effects of the LED illuminated Cu+ZnO Np showed accelerated wound healing with increased wound contraction, collagen deposition, angiogenesis, and re-epithelialization.

Phyto-ecological studies and distribution pattern of plant species and communities of Dhirkot, Azad Jammu and Kashmir, Pakistan.

Plant species represent the hierarchical expression of vegetation as it is affected by various environmental gradients. We explored the plant species composition, distribution pattern, communities formation and their respective indicators under the influence of various environmental factors in the Dhirkot region, Azad Jammu and Kashmir. It was hypothesized that different environmental factors were responsible for the formation of various plant communities each with a distinct indicator. Quantitative ecological techniques were used for the sampling of vegetation. A total of 114 quadrats were established in 13 selected sampling sites. Phytosociological attributes were calculated for each plant species at each quadrat. Soil samples were collected and analyzed using different standard protocols. All the collected data were analyzed using Cluster Analysis, Indicator Species Analysis and Canonical Correspondence Analysis of PCORD and CANOCO software, respectively. A total of 145 plant species were recorded belong to 62 different families. Asteraceae and Lamiaceae were the dominant families, represented by 12 species each (8.27%). Cluster Analysis classify all the stations and plants into four major plant communities as 1) Olea-Desmodium-Prunilla community. 2) Abies-Zanthoxylum-Pteracanthus community 3) Cedrus-Elaeagnus-Hypericum community 4) Alnus-Myrsine-Ranunculus community. Soil pH, electrical conductivity, soil saturation, organic matter and altitude were the significant environmental factors that play its essential role in the plant species distribution, composition, formation of major plant communities and their respective indicators in the region. It is recommended that the identified indicator and rare plant species of the investigated area can further be grown for conservation and management purposes in in-situ environment.

Biofilm forming rhizobacteria enhance growth and salt tolerance in sunflower plants by stimulating antioxidant enzymes activity.

Salinity stress is one of the major environmental stresses that impose global socio-economic impacts, as well as hindering crop productivity. Halotolerant plant growth-promoting rhizobacteria (PGPR) having potential to cope with salinity stress can be employed to counter this issue in eco-friendly way. In the present investigation, halotolerant PGPR strains, AP6 and PB5, were isolated from saline soil and characterized for their biochemical, molecular and physiological traits. Sequencing of 16 S rRNA gene and comparative analysis confirmed the taxonomic affiliation of AP6 with Bacillus licheniformis and PB5 with Pseudomonas plecoglossicida. The study was carried out in pots with different levels of induced soil salinity viz. 0, 5, 10 and 15 dSm-1 to evaluate the potential of bacterial inoculants in counteracting salinity stress in sunflower at different plant growth stages (30, 45 and 60 days after sowing). Both the bacterial inoculants were capable of producing indole acetic acid and biofilm, solubilizing inorganic rock phosphate, and also expressed ACC deaminase activity. The PGPR inoculated plants showed significantly higher fresh and dry biomass, plant height, root length and yield plant-1. Ameliorative significance of applied bacterial inoculants was also evidenced by mitigating oxidative stress through upregulation of catalase (CAT), superoxide dismutase (SOD) and guaiacol peroxidase (GPX) antioxidant enzymes. Increase in photosynthetic pigments, gas exchange activities and nutrient uptake are crucial salt stress adaptations, which were enhanced with the inoculation of salt tolerant biofilm producing PGPR in sunflower plants. Although increase in salinity stress levels has gradually decreased the plant's output compared to non-salinized plants, the plants inoculated with PGPR confronted salinity stress in much better way than uninoculated plants. Owing to the wide action spectrum of these bacterial inoculants, it was concluded that these biofilm PGPR could serve as effective bioinoculants and salinity stress alleviator for sunflower (oil seed crop) by increasing crop productivity in marginalized agricultural systems.