Tripolyphosphate crosslinked Triticum aestivum (wheatgrass) functionalized antimicrobial chitosan: Ameliorating effect on physicochemical, mechanical, invitro cytocompatibility and cell migration properties

Investigation and Biological Assessment of Rumex vesicarius L. Extract: Characterization of the Chemical Components and Antioxidant, Antimicrobial, Cytotoxic, and Anti-Dengue Vector Activity

The objective of this study was to assess the biological potency and chemical composition of Rumex vesicarius aboveground parts using GC-MS. In this approach, 44 components were investigated, comprising 99.99% of the total volatile compounds. The major components were classified as fatty acids and lipids (51.36%), oxygenated hydrocarbons (33.59%), amines (7.35%), carbohydrates (6.06%), steroids (1.21%), and alkaloids (0.42%). The major components were interpreted as 1,3-dihydroxypropan-2-yl oleate (oxygenated hydrocarbons, 18.96%), ethyl 2-hydroxycyclohexane-1-carboxylate (ester of fatty acid, 17.56%), and 2-propyltetrahydro-2H-pyran-3-ol (oxygenated hydrocarbons, 11.18%). The DPPH antioxidant activity of the extracted components of R. vesicarius verified that the shoot extract was the most potent with IC₅₀ = 28.89 mg/L, with the percentages of radical scavenging activity at 74.28% ± 3.51%. The extracted plant, on the other hand, showed substantial antibacterial activity against the diverse bacterial species, namely, Salmonella typhi (23.46 ± 1.69), Bacillus cereus (22.91 ± 0.96), E. coli (21.07 ± 0.80), and Staphylococcus aureus (17.83 ± 0.67). In addition, the extracted plant was in vitro assessed as a considerable anticancer agent on HepG2 cells, in which MTT, cell proliferation cycle, and DNA fragmentation assessments were applied on culture and treated cells. The larvicidal efficacy of the extracted plant was also evaluated against Aedes aegypti, the dengue disease vector. As a result, we may infer that R. vesicarius extract increased cytocompatibility and cell migratory capabilities, and that it may be effective in mosquito control without causing harm.

Antimicrobial and cytotoxic capacity of pyroligneous extracts films of Eucalyptus grandis and chitosan for oral applications

Chitosan films containing distilled pyroligneous extracts of Eucalyptus grandis (DPEC), characterized and developed by Brazilian Agricultural Research Corporation-Embrapa Temperate Agriculture (EMBRAPA-CPACT), were evaluated for antimicrobial activity against Candida albicans, Streptococcus mutans, and Lactobacillus acidophilus by direct contact test. Further, their capacity for the prevention of teeth enamel demineralization and cytotoxicity in vitro were also determined. The natural polymers were tested at different concentrations (1500-7500 µg mL-1) and the formulation of an experimental fluoride varnish with antimicrobial activity was evaluated by direct contact test, whereas cytotoxicity was analyzed through the colorimetric MTT assay. Preliminary data showed no statistically significant differences in cytotoxicity to NIH/3T3 cell line when DPEC is compared to the control group. On the other hand, the antimicrobial capacity and demineralization effects were found between the test groups at the different concentrations tested. Chitosan films containing distilled pyroligneous extracts of E. grandis may be an effective control strategy to prevent biofilm formation related to dental caries when applied as a protective varnish. They may inhibit the colonization of oral microorganisms and possibly control dental caries through a decrease in pH and impairment of enamel demineralization.

Therapeutic candidates for keloid scars identified by qualitative review of scratch assay research for wound healing

The scratch assay is an in vitro technique used to analyze cell migration, proliferation, and cell-to-cell interaction. In the assay, cells are grown to confluence and then ‘scratched’ with a sterile instrument. For the cells in the leading edge, the resulting polarity induces migration and proliferation in attempt to ‘heal’ the modeled wound. Keloid scars are known to have an accelerated wound closure phenotype in the scratch assay, representing an overactivation of wound healing. We performed a qualitative review of the recent literature searching for inhibitors of scratch assay activity that were already available in topical formulations under the hypothesis that such compounds may offer therapeutic potential in keloid treatment. Although several shortcomings in the scratch assay literature were identified, caffeine and allicin successfully inhibited the scratch assay closure and inflammatory abnormalities in the commercially available keloid fibroblast cell line. Caffeine and allicin also impacted ATP production in keloid cells, most notably with inhibition of non-mitochondrial oxygen consumption. The traditional Chinese medicine, shikonin, was also successful in inhibiting scratch closure but displayed less dramatic impacts on metabolism. Together, our results partially summarize the strengths and limitations of current scratch assay literature and suggest clinical assessment of the therapeutic potential for these identified compounds against keloid scars may be warranted.

UV responsive quercetin derived and functionalized CuO/ZnO nanocomposite in ameliorating photocatalytic degradation of rhodamine B dye and enhanced biocidal activity against selected pathogenic strains

Quercetin was investigated for its role as a reducing agent in biosynthesizing CuO/ZnO nanocomposite, its subsequent surface functionalization and influence in Rhodamine B dye degradation and biocidal activity. The as synthesized quercetin functionalized CuO/ZnO nanocomposite (CuO/ZnO@Q) was analyzed using X-ray diffraction (XRD), Fourier transform infra red spectroscopy (FTIR), Transmission electron microscopy (TEM), Energy dispersive spectroscopy (EDS) and Ultraviolet-visible spectroscopy (UV-Vis). XRD showed the formation of crystalline CuO, ZnO phases and FTIR analysis revealed the incorporation of quercetin functional groups in the synthesized nanocomposite. TEM image displayed the formation of quercetin deposited spherical CuO/ZnO nanostructure with the EDAX results confirming the presence of organic carbon composition from quercetin. The UV absorption spectra ascertained the presence and role of quercetin in the enhanced absorption of radiation in the UV range. CuO/ZnO@Q showed improved photocatalysis with complete Rhodamine B dye degradation after 75 min of UV irradiation, as against pure CuO/ZnO, which exhibited incomplete dye degradation even after 90 min of irradiation. Moreover, quercetin surface functionalization effectively ameliorated its antimicrobial activity against E. coli, S. aureus, Shigella, B. subtilis, A. niger and C. albicans, proving its potential in significantly enhancing biocidal activity along with photocatalytic dye degradation in a natural and eco-friendly route.

Preparation and Characterization of TPP-Chitosan Crosslinked Scaffolds for Tissue Engineering

Scaffolds are three-dimensional porous structures that must have specific requirements to be applied in tissue engineering. Therefore, the study of factors affecting scaffold performance is of great importance. In this work, the optimal conditions for cross-linking preformed chitosan (CS) scaffolds by the tripolyphosphate polyanion (TPP) were investigated. The effect on scaffold physico-chemical properties of different concentrations of chitosan (1 and 2% w/v) and tripolyphosphate (1 and 2% w/v) as well as of cross-linking reaction times (2, 4, or 8 h) were studied. It was evidenced that a low CS concentration favored the formation of three-dimensional porous structures with a good pore interconnection while the use of more severe conditions in the cross-linking reaction (high TPP concentration and crosslinking reaction time) led to scaffolds with a suitable pore homogeneity, thermal stability, swelling behavior, and mechanical properties, but having a low pore interconnectivity. Preliminary biocompatibility tests showed a good osteoblasts’ viability when cultured on the scaffold obtained by CS 1%, TPP 1%, and an 8-h crosslinking time. These findings suggest how modulation of scaffold cross-linking conditions may permit to obtain chitosan scaffold with properly tuned morphological, mechanical and biological properties for application in the tissue regeneration field.