•Green synthesis of AgNPs nanoparitcles using Hardwickia binata.•The synthesized AgNPs were characterized by UV, XRD, IR, FE-SEM-EDAX, and HR-TEM with SAED pattern.•The synthesized AgNPs shows a ...Spherical shape of nanoparticles.•The synthesized AgNPs demonstrated excellent biological & photo-catalytic activities.
In this study, synthesized AgNPs were produced using an aqueous leaf extract of Hardwickia binata. The highest absorption wavelength was found to be at 454 nm. The study evaluated the antibacterial activity of the synthesized AgNPs and found that they exhibited the highest zone of inhibition against B. subtilis, indicating good antibacterial activity. The antioxidant activity evaluated using DPPH, ABTS assays and further analyzed the synthesized AgNPs for their anti-inflammatory and anti-proliferative activity. In an environmental related study, the degradation of Methylene Blue (MB) dye using the synthesized AgNPs. The results showed that the MB dye was completely degraded within 210 min, suggesting that the synthesized AgNPs have potential as treatment option for dye-containing wastewater. The findings of the study synthesized AgNPs the antioxidant, anti-inflammatory, anticancer and good dye degradation properties. The current research holds promise for addressing the issue of removing hazardous dyes from wastewater discharged by many industries.
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•Phenolic composition of black, red and white quinoa grains was evaluated.•Quercetin and kaempferol derivatives were present in all quinoa varieties.•None of the quinoa varieties ...showed toxicity in hepatotoxocity assay.•All hydroethanolic extracts possessed antibacterial and antifungal activity.
The ingestion of bioactive compounds has revealed health benefits, namely in the prevention and/or treatment of several diseases. This work aims to characterize the phenolic profile of three colour varieties of Chenopodium quinoa Willd. grains (black, red and white), and also evaluate their cytotoxic and antimicrobial activity. All varieties revealed the presence of phenolic compounds, namely, quercetin and kaempferol derivatives. In this study, quinoa grains did not reveal any anti-proliferative capacity in tumour cell lines, and, as expected, they were devoid of any toxicity. All of the analysed extracts possessed antibacterial and antifungal activities (inhibitory and bactericidal/fungicidal) against the microbial strains considered, exhibiting promising values of minimum bactericidal concentrations (mean MBC 0.153–0.916 mg/mL) and minimum fungicidal concentrations (mean MFC 0.211–0.884 mg/mL). Quinoa varieties represent a good source of bioactive compounds, interfering beneficially in the organism, specifically as antimicrobial agents. Thus, these extracts could be used in the development of bioactive ingredients.
Anti-listeria and functional characteristics of postbiotics (metabolic byproducts of probiotics) of Lactobacillus acidophilus LA5 and L. casei 431 and L. salivarius were investigated in vitro, and in ...ground meat and whole milk. Antibacterial activity of all examined postbiotics was mainly associated to pyrrolo 1,2-a pyrazine-1,4-dione and somewhat to the presence of different organic acids. Postbiotics of all Lactobacillus spp. maintained their residual antimicrobial activity over 50% at different pH levels (4, 5, 6, 7, 8 and 9). Postbiotics also exhibited a biofilm removal activity on L. monocytogenes, this activity depended on the type of postbiotics and the contact time. Lower minimum effective concentration (MEC) of postbiotics were varied in food models and remarkably, a low MEC index (15 mg/mL) was observed for postbiotics of L. salivarius. The postbiotics prepared from lactobacillus spp. especially L. salivarius has an applicable functional property in vitro and in food models.
•Postbiotics of commonly known lactic acid bacteria were characterized.•Antibacterial and biofilm removal activity were measured against L. monocytogenes.•Postbiotics of L. salivarius predominantly showed a significant activity.•Postbiotics was proposed as a safe antimicrobial for food.
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•An intravascular catheter was coated with CMC layer exhibiting antimicrobial, antithrombotic, and low friction properties.•Whole manufacturing process was water-based, hence ...eco-friendly and biocompatible.•Functionalities of CMC layer were enhanced by engineering the porous structure.•Sufficient lubricity of porous CMC coated catheter was verified via trackability test.
Antimicrobial, antithrombotic activity and low-friction functions are essential for the surface of intravascular catheters (ICs). However, the multifunctional surface, encompassing all of the above properties has not yet been realized. Here, we report a novel strategy for biocompatible and eco-friendly surface modification of the ICs with multifunctional polysaccharide, O-carboxymethyl chitosan (CMC). Micro- and nanoscale porous CMC (p-CMC) layer was simply fabricated via a selective elimination of the water-soluble polyethylene glycol (PEG) from heterogeneous CMC/PEG composite. The p-CMC structure exhibited a significantly enhanced hydration rate and superhydrophilic property. In particular, the antifouling property of superhydrophilic surface showed excellent anti-adhesion of Escherichia coli and platelets along with the intrinsic multifunctionality of CMC, indicating a dual effect of our p-CMC layer: (1) intrinsic antibacterial and antithrombotic properties of CMC and (2) anti-adhesion of substances on superhydrophilic surface. Meanwhile, despite the rough surface of the p-CMC layer, it showed high lubricity and durability under continuous wet friction conditions. Furthermore, we demonstrated that the actual p-CMC coated intravascular catheter (IC) provides superior trackability in a curved artificial blood vessel. The potential of the proposed coating strategy can be offered not only ICs, but also wide range of polymer-based applications including vascular filters, grafts, pacemakers and soft robots.
The use of sulfur dioxide (SO2) as wine additive is able to ensure both antioxidant protection and microbiological stability. In spite of these undeniable advantages, in the last two decades the ...presence of SO2 in wine has raised concerns about potential adverse clinical effects in sensitive individuals. The winemaking industry has followed the general trend towards the reduction of SO2 concentrations in food, by expressing at the same time the need for alternative control methods allowing reduction or even elimination of SO2. In the light of this, research has been strongly oriented toward the study of alternatives to the use of SO2 in wine. Most of the studies have focused on methods able to replace the antimicrobial activity of SO2. This review article gives a comprehensive overview of the current state‐of‐the‐art about the chemical additives and the innovative physical techniques that have been proposed for this purpose. After a focus on the chemistry and properties of SO2 in wine, as well as on wine spoilage and on the conventional methods used for the microbiological stabilization of wine, recent advances on alternative methods proposed to replace the antimicrobial activity of SO2 in winemaking are presented and discussed. Even though many of the alternatives to SO2 showed good efficacy, nowadays no other physical technique or additive can deliver the efficacy and broad spectrum of action as SO2 (both antioxidant and antimicrobial), therefore the alternative methods should be considered a complement to SO2 in low‐sulfite winemaking, rather than being seen as its substitutes.
This study aimed to investigate and compare the total phenolic content (TPC) and total flavonoid content (TFC) and antioxidant and antibacterial activities of different extracts recovered from Date ...Palm Pollen collected from Tunisian cultivars of Kerkennah (DPP-K) and Tozeur (DPP-T) using various solvents, including hexane, chloroform, ethyl acetate, acetone, ethanol and water. The results revealed that DPP-T had higher TPC than DPP-K for all solvent extracts, except for hexane, with a value of 237.74±9.58mg GAE/g for the water extract. The highest level of TFC (75.10±4.37mg QE/g) was recorded in the acetone DPP-T extract, which was about twice as high as that of DPP-K. A total of eight phenolic compounds were identified and quantified in both extracts by HPLC, namely gallic acid, catechin, caffeic acid, epicatechin, vanillic acid, coumarin, quercitin and rutin. The antioxidant activities of the extracts were screened using DPPH and β-carotene bleaching assays. The results indicated that the DPP-T acetone extract showed the best DPPH scavenging activity (IC50=46.56±0.28μg/ml), with no activity being recorded for DPP-K. The DPP-T extract also showed significant effects in terms of the β-carotene test (28.12±0.04μg/ml) when compared to BHT as a reference standard. The extracts were screened for antimicrobial activity against 10 bacterial and 7 fungal strains, and the results showed that ethyl acetate DPP-K extract exhibited the strongest activity against Listeria monocytogenes and that the Staphylococcus aureus strain was most sensitive to DPP-T, with MIC and MBC values of 0.98mg/ml and 1.95mg/ml, respectively. Both DPP-T and DPP-K showed strong inhibition effects on the growth of oxysporum. Further time kill assays demonstrated the potency of DPP-K and DPP-T ethyl acetate extracts to inhibit the growth of L. monocytogenes and S. aureus, respectively. Overall, the findings suggest that DPP could be considered a promising source of new natural antioxidant and antimicrobial agents for use in various food and pharmaceutical products and formulations. This suggested that the DPP extract is a good potential inhibitor of food spoiling microbial growth and could be a highly effective therapeutic choice for human and plant infections.
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The unprecedently rearranged 6/5/8/6/5 pentacyclic monoterpenoid indole alkaloid voafriamidine from Voacanga africana contains an uncommon N-acyl amidine structural motif that forms a ...unique 2,4-diazatricycle-6,5,11,8,03,7 tetradecane skeleton. Despite the lack of proper NMR correlations for the related quaternary carbon and nitrogen, the complex structure was finally elucidated by the combination of ACD/Structure Elucidator, density functional theory (DFT) calculations of the NMR spectra and electronic circular dichroism (ECD) analyses.
Experimental design methodology (mixture design) coupled to microdilution assay were used to study the potential interactions between several active compounds from three Moroccan essential oils (EOs) ...(M. pulegium, O. mixta and M. piperita) against S. aureus E. coli and C. tropicalis, to increase their sensitivity and to predict optimal formulations. EOs extraction was firstly obtained by hydrodistillation, then, their chemical composition was determined by GC/MS and their antimicrobial activity was evaluated. The optimization of antimicrobial activity of essential oils mixtures by augmented simplex-centroid design allowed us to model and validate statistically as well as to establish a prediction profile of the studied phenomena. The optimization of mixtures antimicrobial activities has highlighted the synergistic effect between M. piperita and M. pulegium essential oils. The optimal mixture predicted against E. coli, S. aureus and C. tropicalis corresponded to 54%/46%; 56%/44% and 55%/45% of M. piperita and M. pulegium essential oils, respectively. This study shows that the combination of essential oils may be applicable in the fight against emerging microbial drug resistance or useful as natural food preservatives.
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•Antibacterial activity of three essential oils was tested alone and in combination.•Optimal formulation for all studied strains was identified by mixture design.•Synergistic effect between essential oils was highlighted.•Hight synergy was observed for M. piperita/M. pulegium essential oils combination.
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