Strong Antibacterial Activity Research Articles

Exploring the bioactive potential of Mentha longifolia from Northeast India: an inclusive study on phytochemical composition and biological activities

Mentha longifolia (Lamiaceae) is regarded as highly valuable aromatic medicinal species with wide range of pharmaceutical application. In the present work, leaf essential oil of M. longifolia was applied for the assessment of in vitro pharmacological potentials and compositional analysis. A sum of 15 compounds were detected by GC-FID and GC-MS analysis of M. longifolia essential oil with total area of 99.98% where major compounds were carvone (59.56%), D-limonene (20.81%), eucalyptol (10.08%). The anti-oxidant potency of M. longifolia was estimated using two methods viz., ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assay where M. longifolia essential oil showed moderate anti-oxidant potency. M. longifolia essential oil revealed high anti-inflammatory and tyrosinase inhibitory activity with an IC50 value 3.68 μL/mL and 1.22 μL/mL respectively compared to standard sodium diclofenac (5.33 μL/mL) and kojic acid (2.28 μL/mL). The acetylcholinesterase (AchE) inhibitory and genotoxic assay was performed, where M. longifolia essential oil revealed strong anti-acetylcholinesterase and anti-genotoxic activity. Anti-microbial potential of M. longifolia essential oil was also where strong anti-bacterial activity was shown against Salmonella typhimurium, Bacillus cereus, Staphylococcus aureus, Micrococcus luteus. For anti-fungal activity, M. longifolia essential oil showed no zone of inhibition against any used strains except Aspergillus flavus. From the present research it was established that M. longifolia essential oil possesses pharmaceutical potential with strong AchE inhibitory, anti-inflammatory, anti-microbial, anti-tyrosinase, anti-genotoxic and anti-oxidant activity which can be used for plant-based drug development in future endeavor.

Characterization of the novel broad-spectrum lytic phage Phage_Pae01 and its antibiofilm efficacy against Pseudomonas aeruginosa

IntroductionPseudomonas aeruginosa is present throughout nature and is a common opportunistic pathogen in the human body. Carbapenem antibiotics are typically utilized as a last resort in the clinical treatment of multidrug-resistant infections caused by P. aeruginosa. The increase in carbapenem-resistant P. aeruginosa poses an immense challenge for the treatment of these infections. Bacteriophages have the potential to be used as antimicrobial agents for treating antibiotic-resistant bacteria.Methods and ResultsIn this study, a new virulent P. aeruginosa phage, Phage_Pae01, was isolated from hospital sewage and shown to have broad-spectrum antibacterial activity against clinical P. aeruginosa isolates (83.6%). These clinical strains included multidrug-resistant P. aeruginosa and carbapenem-resistant P. aeruginosa. Transmission electron microscopy revealed that the phage possessed an icosahedral head of approximately 80 nm and a long tail about 110 m, indicating that it belongs to the Myoviridae family of the order Caudovirales. Biological characteristic analysis revealed that Phage_Pae01 could maintain stable activity in the temperature range of 4~ 60°C and pH range of 4 ~ 10. According to the in vitro lysis kinetics of the phage, Phage_Pae01 demonstrated strong antibacterial activity. The optimal multiplicity of infection was 0.01. The genome of Phage_Pae01 has a total length of 93,182 bp and contains 176 open reading frames (ORFs). The phage genome does not contain genes related to virulence or antibiotic resistance. In addition, Phage_Pae01 effectively prevented the formation of biofilms and eliminated established biofilms. When Phage_Pae01 was combined with gentamicin, it significantly disrupted established P. aeruginosa biofilms.ConclusionWe identified a novel P. aeruginosa phage and demonstrated its effective antimicrobial properties against P. aeruginosa in both the floating and biofilm states. These findings offer a promising approach for the treatment of drug-resistant bacterial infections in clinical settings.

Enhanced biosafety, anticancerand antibacterial photodynamic activities using silver-pyropheophorbide-a nanoconjugates.

Aim: A study of the enhancement of photodynamic activities of pyropheophorbide-a using PG-Ag-PPa nanoconjugates. Materials & methods: The nanoconjugates were formulated from silver nanoparticles and PPa via amide linkage, then characterized, and their photodynamic activities were examined. Results: The nanoconjugates displayed a higher rate of reactive oxygen species generation, commendable cellular uptake by Eca-109 cancer cells, higher photocytotoxicity toward the cancer cellsand better bio-safety. They revealed strong antibacterial activity against Escherichia coli following internal reactive oxygen species generation and membrane disintegration. The in vivo anticancer studies confirmed higher cytotoxicity of thenanoconjugatestoward cancer cells and better safety than PPa. Conclusion: Therefore, PG-Ag-PPa nanoconjugates could be considered potential nano photosensitizers for photodynamic therapy of tumors and bacterial infection with good bio-safety.

Antibacterial activity of jamblang leaf ethanol extract (Syzygium cumini) against the growth of Propionibacterium acnes

Background: Propionibacterium acnes is a bacterium found on the skin that plays a significant role in acne vulgaris. The inappropriate use of antibiotics can lead to resistance, necessitating the search for alternative therapies from plants with high antibacterial potential. One such plant is jamblang (Syzygium cumini), which has demonstrated antibacterial properties. Objective: This research aims to test the antibacterial activity of jamblang leaf extract against the growth of P. acnes. Method: The study employed an experimental design with a posttest-only control group design. The treatment groups consisted of a positive control (clindamycin), a negative control (sterile distilled water), and jamblang leaf extract groups with concentrations of 100%, 50%, 25%, 12.5%, and 6.25% (n=4). Data analysis was conducted using the One-Way ANOVA statistical test. Results: The jamblang leaf extract exhibited antibacterial potential against the growth of P. acnes. The extract showed strong antibacterial activity at concentrations of 100%, 50%, 25%, and 12.5%, and moderate antibacterial activity at a concentration of 6.25%. Conclusion: This suggests that jamblang leaf extract could be a promising alternative therapy for treating acne vulgaris, offering a natural solution to combat antibiotic resistance.

EGCG induced the formation of protein nanofibrils hydrogels with enhanced anti-bacterial activity

The functional properties of the amyloid fibrils could be further improved after physical modification. Simply adding epigallocatechin gallate (EGCG) to ovalbumin amyloid fibrils (OAFs) could successfully drive the formation of hydrogels through the self-assembly of hybrid supermolecules, however the functional properties of amyloid fibrils as well as the underlying formation mechanisms have not been well revealed. In present study, the rheological properties, thermal stability, and morphology of the resulting OAFs hydrogels were investigated, and the secondary structural changes of the proteins in OAFs hydrogels was analyzed. The results showed that the addition of EGCG would affect the diameter of OAFs, mainly as the concentration of EGCG increased from 0.1% to 2%, the diameter of OAFs increased from 3 nm to 5.5 nm. In addition, when the EGCG concentration increased from 0.1% to 0.5%, the content of β-sheet structure increased from 24.3% to 43.7%. Moreover, the OAFs hydrogels exhibited good viscoelasticity and heat resistance, as well as displayed good antioxidant activity and strong anti-bacterial activity against both Gram-negative and Gram-positive bacteria. The present study might provide a theoretical basis for antimicrobial food packaging based on animal amyloid fibrils hydrogels.

SYNERGISTIC EFFECTS OF NEEM OIL AND GENTAMICIN ON PSEUDOMONAS AERUGINOSA VIA PHZM GENE DOWNREGULATION: A COMPREHENSIVE REVIEW

Exploring the antibacterial potential of neem oil (Azadirachta indica) in combination with gentamicin (GEN) against pathogenic molds, especially Pseudomonas aeruginosa, has drawn concern due to the quest for natural treatment options against incurable diseases. Prospective research directions include looking for natural cures for many of the currently incurable diseases available now. microbial identification system, were used to identify the isolates. The research utilized a range of methods, such as the diffusion agar well (AWD) assays, TEM (transmission electron microscopy) analysis, minimum inhibitory concentration (MIC) assays, and real-time PCR (RT-qPCR) to analyze bacterial expression and the antibacterial action of neem oil (Azadirachta indica) combined with gentamicin (GEN) against the pathogenic bacteria Pseudomonas aeruginosa between others. The combined effects of neem oil and GEN on P. aeruginosa are extensively investigated in this study, with particular attention paid to the downregulation of the virulent factor gene phzM, inhibition of biofilm formation, morphological changes, and gene expression, in that proportion. Results show that neem oil has strong antibacterial activity against P. aeruginosa and S. aureus, preventing the formation of biofilms and causing morphological alterations. In addition, the synergistic effects of neem oil and GEN are demonstrated, together in order with the downregulation of the phzM gene in P. aeruginosa. These results highlight the increased effectiveness of neem oil when combined with GEN and point to the potential of the oil as a stand-alone antibacterial agent. They also highlight the need for more study to overcome antibiotic resistance in harmful bacteria. Overall, our results point to a possibility that neem oil extract, either alone or in combination with GEN, can suppress the development of pathogenic microbes. This synergistic impact is related to the downregulation of a virulence factor gene. To address the drug resistance linked to pathogenic microbes, greater study is required. Novelty of study addresses the important issue of antibiotic resistance by exploring the potential synergistic effects of neem oil and gentamicin on pathogenic bacteria, particularly Pseudomonas aeruginosa. This topic is highly relevant in the context of the global challenge of antimicrobial resistance.Novelty and relevanc the important issue of antibiotic resistance by exploring the potential synergistic effects of neem oil and gentamicin on pathogenic bacteria, particularly Pseudomonas aeruginosa. This topic is highly relevant in the context of the global challenge of antimicrobial resistance.

SYNERGISTIC EFFECTS OF NEEM OIL AND GENTAMICIN ON PSEUDOMONAS AERUGINOSA VIA PHZM GENE DOWNREGULATION: A COMPREHENSIVE REVIEW

Exploring the antibacterial potential of neem oil (Azadirachta indica) in combination with gentamicin (GEN) against pathogenic molds, especially Pseudomonas aeruginosa, has drawn concern due to the quest for natural treatment options against incurable diseases. Prospective research directions include looking for natural cures for many of the currently incurable diseases available now. microbial identification system, were used to identify the isolates. The research utilized a range of methods, such as the diffusion agar well (AWD) assays, TEM (transmission electron microscopy) analysis, minimum inhibitory concentration (MIC) assays, and real-time PCR (RT-qPCR) to analyze bacterial expression and the antibacterial action of neem oil (Azadirachta indica) combined with gentamicin (GEN) against the pathogenic bacteria Pseudomonas aeruginosa between others. The combined effects of neem oil and GEN on P. aeruginosa are extensively investigated in this study, with particular attention paid to the downregulation of the virulent factor gene phzM, inhibition of biofilm formation, morphological changes, and gene expression, in that proportion. Results show that neem oil has strong antibacterial activity against P. aeruginosa and S. aureus, preventing the formation of biofilms and causing morphological alterations. In addition, the synergistic effects of neem oil and GEN are demonstrated, together in order with the downregulation of the phzM gene in P. aeruginosa. These results highlight the increased effectiveness of neem oil when combined with GEN and point to the potential of the oil as a stand-alone antibacterial agent. They also highlight the need for more study to overcome antibiotic resistance in harmful bacteria. Overall, our results point to a possibility that neem oil extract, either alone or in combination with GEN, can suppress the development of pathogenic microbes. This synergistic impact is related to the downregulation of a virulence factor gene. To address the drug resistance linked to pathogenic microbes, greater study is required. Novelty of study addresses the important issue of antibiotic resistance by exploring the potential synergistic effects of neem oil and gentamicin on pathogenic bacteria, particularly Pseudomonas aeruginosa. This topic is highly relevant in the context of the global challenge of antimicrobial resistance.Novelty and relevanc the important issue of antibiotic resistance by exploring the potential synergistic effects of neem oil and gentamicin on pathogenic bacteria, particularly Pseudomonas aeruginosa. This topic is highly relevant in the context of the global challenge of antimicrobial resistance.

Fabrication of curcumin conjugated self-assembled lysozyme nanoparticle as potential food additive with enhanced antibiofilm and antioxidant activity

Food contamination has recently emerged as a major global challenge. Due to the potential side effects of synthetic preservatives, natural-based alternatives with antimicrobial and antibiofilm properties have been developed to prevent food spoilage. This approach involves utilizing biomolecules like proteins, which can undergo self-assembly to form stable nanostructures with enhanced functionalities. Here, we prepared self-assembled nanostructured lysozyme (SaLyz) using two different crosslinkers: Sodium tripolyphosphate (STPP) and Glutaraldehyde (GTD). SaLyz1, prepared with a single crosslinker (STPP), had a size of 80 nm, while SaLyz2, prepared with a double crosslinker (GTD + STPP), had a size of 60 nm. SaLyz2, with a zeta potential of −29 mV, showed greater stability at high pH and temperature. To enhance the antibacterial and antibiofilm activity of SaLyz, the natural polyphenol curcumin was loaded onto SaLyz1 and SaLyz2. SaLyz2-Cur exhibited the highest antibacterial efficacy, with growth inhibition rates of 91% against E. coli and 93.7% against B. subtilis. Additionally, this formulation demonstrated excellent antibiofilm activity, inhibiting over 86% and 88% of E. coli and B. subtilis biofilm formation, respectively. Furthermore, the particles eradicated preformed mature biofilms of E. coli and B. subtilis at rates of 74% and 80%, respectively. The developed SaLyz possessed significant antioxidant properties, which were further enhanced after curcumin loading. In vitro hemocompatibility and cytocompatibility studies showed that SaLyz and SaLyz-Cur were highly biocompatible, indicating their safety for consumption. Hence, the prepared formulations, with their strong antibacterial, antibiofilm, and antioxidant activities, can be utilized as natural food preservatives to prevent food spoilage.

Avocado (Persea americana Mill.) Postharvest Organic Nutritional Conservation Employing Carboxyl Methylcellulose (CMC) Manufactured Out from Moringa Plant

The research concluded that the use of extracts of moringa leaves and moringa seed as an edible coating might help to preserve the shelf life and also the quality of Avocado. The cultivars that were focused on during this research were “Hass” and “Gem”. It may also reduce the risk of infection and inflammation in these cultivars. Methanolic and ethanolic moringa extracts were also examined for their antifungal properties. Shortly, 1% Carboxyl methylcellulose which is shown as CMC and 2% MLE which is Moringa Leaf Extract or MSE which is moringa seed extract, were combined. The fruit was either coated with either (MLE + CMC) or that of (MSE + CMC) and then it was kept at a temperature of 5.5°C and 95% relative humidity (RH) for a period of 21 days. The fruit was kept at ambient temperatures i.e. 21°C and 60% RH, after being refrigerated to approximate retailing conditions. Fruit firmness and postharvest quality indicators including ethylene production and respiration rate were analyzed. In relation to potato dextrose agarose which is shortened as PDA, both coatings were also evaluated for their effectiveness against the fungus which may spoil the fruit quality during postharvest opperations. Compared to uncoated fruit, the coated fruit was noticed to have less mass loss. Respiration rates were also observed to be decreased along with Ethylene production, in a contrast to the uncoated fruit. A. alternata and C. gloeosporioides were both inhibited by ethanol leaf extract by 43.60% and 42.90%, respectively. All pathogens exposed to coverings had damaged hyphal structures, while uncoated fruit had healthy hyphal structures. Stronger antibacterial activity was observed in ethanolic moringa leaf extracts as compared to the extracts that were derived from methanol. The outcomes of this research showed that carboxyl methylcellulose CMC containing moringa extract reduces illnesses in fruit. Throughout the postharvest supply chain, it also maintains the general quality of avocados. The shelf life of the avocado was remarkably increased. The avocado sector may eventually commercialize the moringa extracts combined with carboxyl methylcellulose, as a new organic edible covering.

Biosynthesis, Antibacterial and Antifungal Activities of Ag Nanoparticles Prepared Using Piper nigrum Fruit Extract

Nanomaterials are promising alternatives to antibiotics with the potential to handle the menace of emerging multidrug resistance in pathogenic microbes. We report a simple biosynthetic approach to prepare Ag nanoparticles (NPs) with strong antibacterial and antifungal actions by using Piper nigrum fruit extract as a bioreducing agent. The biosynthesized material was characterized by SEM, AFM, TEM, HRTEM, XRD and UV–Visible absorption spectroscopy. SEM, AFM and TEM analyses provided evidence that the average diameter of the Ag NPs was 18[Formula: see text]nm, while XRD and HRTEM confirmed the FCC structure of Ag NPs. The biosynthesized Ag NPs demonstrated extremely strong antibacterial activity against Bacillus oceanisediminis and Escherichia coli, and showed extremely strong antifungal action against Schizosaccharomyces pombe, inhibiting their growth at very low concentrations of 3[Formula: see text][Formula: see text]g/mL, 4[Formula: see text][Formula: see text]g/mL and 3[Formula: see text][Formula: see text]g/mL, respectively. The molecular origin of their antibacterial and antifungal activity was studied using various molecular and biochemical assays. The results of these assays revealed a major role for reactive oxygen species (ROS) in the antifungal and antibacterial actions of the biosynthesized Ag NPs. Furthermore, morphological changes in cells and cell wall damage upon Ag NP treatment were observed by scanning electron microscopy. In addition, significant enhancement in protein leakage and fragmentation of DNA was also observed upon treatment of S. pombe, B. oceanisediminis and E. coli with Ag NPs. In conclusion, the observed extremely strong antibacterial and antifungal activities of biosynthesized Ag NPs are due to the oxidative stress triggered by ROS, causing cell wall damage and subsequent protein leakage and DNA fragmentation.

Antimicrobial peptide 2K4L inhibits the inflammatory response in macrophages and Caenorhabditis elegans and protects against LPS-induced septic shock in mice

2K4L is a rationally designed analog of the short α-helical peptide temporin-1CEc, a natural peptide isolated and purified from the skin secretions of the Chinese brown frog Rana chensinensis by substituting amino acid residues. 2K4L displayed improved and broad-spectrum antibacterial activity than temporin-1CEc in vitro. Here, the antibacterial and anti-inflammatory activities of 2K4L in macrophages, C. elegans and mice were investigated. The results demonstrated that 2K4L could enter THP-1 cells to kill a multidrug-resistant Acinetobacter baumannii strain (MRAB 0227) and a sensitive A. baumannii strain (AB 22933), as well as reduce proinflammatory responses induced by MRAB 0227 by inhibiting NF-κB signaling pathway. Similarly, 2K4L exhibited strong bactericidal activity against A. baumannii uptake into C. elegans, extending the lifespan and healthspan of the nematodes. Meanwhile, 2K4L alleviated the oxidative stress response by inhibiting the expression of core genes in the p38 MAPK/PMK-1 signaling pathway and downregulating the phosphorylation level of p38, thereby protecting the nematodes from damage by A. baumannii. Finally, in an LPS-induced septic model, 2K4L enhanced the survival of septic mice and decreased the production of proinflammatory cytokines by inhibiting the signaling protein expression of the MAPK and NF-κB signaling pathways and protecting LPS-induced septic mice from a lethal inflammatory response. In conclusion, 2K4L ameliorated LPS-induced inflammation both in vitro and in vivo.

Analysis and identification of the main antimicrobial metabolites of Lactobacillus plantarum LPZN19

BackgroundLactobacillus plantarum can produce many secondary metabolites, some of which have antibacterial effects. This study aimed to explore the main antimicrobial metabolites of Lactobacillus plantarum LPZN19. ResultsThe results of antibacterial activity after fermentation for different durations showed that the metabolites from the LPZN19 cell-free supernatant (LCFS) after 24 h had the strongest antibacterial activity, which was confirmed by the highest contents of organic acids and fatty acids in the LCFS after 24 h. Lactic acid, phenyllactic acid, malic acid, aspartic acid, dodecanoic acid and propionic acid were the main differentially abundant metabolites. LCFS was separated by semi-preparative liquid chromatography to obtain 4 antibacterial parts, mainly organic acids such as lactic acid, glycolic acid, and citric acid, and fatty acids such as stearic acid, palmitic acid, and octanoic acid. In addition, fatty glycerides and amino acids with antimicrobial activity were included. ConclusionsOur findings indicate that the main antimicrobial metabolites of L. plantarum LPZN19 include organic acids, fatty acids, fatty glycerides and some amino acids with antimicrobial activity, which not only clarifies the main antimicrobial metabolites of L. plantarum LPZN19 but also provides an effective method for rapid screening of antimicrobial substances.

Engineered bacterial cellulose-based Ag nanoparticles/g-C3N4/Eucalyptus extract nanocomposites for wound dressing: in vitro evaluation

In recent years, antibacterial wound dressings have gained considerable attention. Bacterial cellulose (BC) has received significant interest due to its unique physiochemical characteristics such as biocompatibility, high porosity, superior mechanical properties, water holding capacity, and nontoxicity. In this work, silver nanoparticles/graphitic carbon nitride/eucalyptus extract (Ag/gCN/EE) nanocomposite was synthesized as an antibacterial agent and incorporated into nanofibrous structures composed of BC. The BC/Ag/gCN/EE and polyvinyl alcohol/BC/Ag/gCN/EE (PVA/BC/Ag/gCN/EE) nanocomposites were synthesized using immersion and electrospinning methods, respectively. Then, the swelling ratio was optimized and the wound dressings were prepared based on the optimal formulation. The release profile, biodegradability and mechanical properties of the wound dressings were assessed. The antibacterial property of Ag/gCN/EE was studied demonstrating strong antibacterial activity on E. coli and S. aureus. MTT assay was carried out on NIH 3T3 fibroblast cells, and BC/Ag/gCN/EE and PVA/BC/Ag/gCN/EE nanocomposites showed 89 ± 2.31% and 96 ± 3.28% viability, respectively and no toxicity. To assess the effect of the composites on in vitro wound healing and cell migration, scratch wound assay was performed. The results indicated that after 24 h, BC/Ag/gCN/EE and PVA/BC/Ag/gCN/EE reduced 18.69 and 23.97% of the scratch area compared to the control group. The prepared composites are promising wound dressings that could accelerate wound healing and kill bacteria simultaneously.

In vitro activity of the novel antimicrobial peptide WR-286 in combination with vancomycin against methicillin-resistant Staphylococcus aureus

Background: Multidrug resistance bacteria are a serious problem for health specialists and all the people in the world. The main reasons for this problem are the misuse of antibiotics and the limited number of antibiotics as compared to different human diseases. The important antibiotic-resistant bacteria include Methicillin-resistant Staphylococcus aureus (MRSA). Antimicrobial peptides (AMPs) are regarded as promising antimicrobial agents because they satisfy the requirements for the creation of innovative antimicrobial drugs. The aim of the study: To design a novel antimicrobial peptide and study its effect against MRSA when we combined it with vancomycin. Materials and methods: To produce the hexapeptide WR-286, 1-(2, 6-difluorobenzyl)-1H-1, 2, 3-triazole-4-carboxylic acid, tryptophan (W), and arginine (R) were rationally combined. Different bacterial strains were used to test WR-286's antibacterial properties. Investigations of WR-286's hemolytic activity toward human erythrocytes were also conducted. Finally, utilizing the checkerboard approach and the fractional inhibitory index, synergistic tests with vancomycin were carried out. Results: With MIC values as low as 35 μM, WR-286 demonstrated strong antibacterial activity against MRSA. The toxicity of WR-286 to human red blood cells was very low. Additionally, the peptide and vancomycin's activity were improved by the synergistic experiments. Conclusion: According to the current investigation, WR-286 has little hemolytic activity and displays promising antibacterial activity against MRSA. Additionally, when coupled with vancomycin, the peptide has synergistic effect. The novel AMPs described in this work are promising potential candidates for antimicrobial drug development.

An In-vitro Antioxidant and Antimicrobial Activity of Vitis vinifera Leaf Extract

Background: Vitis vinifera (Flame red grape) is known for its hepatoprotective, nephroprotective and cardioprotective activity of ethanolic and aqueous extracts of aerial parts has been reported but, due to presence of polyphenols, glycosides, saponins and alkaloid, the antioxidant and antimicrobial activity yet not to evaluated on salad plant and bacteria, respectively. Aim: This research examined grape (V. vinifera flaming red) leaf ethanolic extract (EE) as a bioactive resource. Methods: Ethanolic extract test, primarily to calculate the overall phenolic content by using the Folin-Ciocalteu technique and gallic acid taking as a reference. Similarly, flavonoid content measured using quercetin as a calibration curve. Antioxidant properties was confirmed by getting positive responses from different methods (DPPH, H2O2, FRAP and Phospho-Molybdenum). Antimicrobial activity tested against gram-positive bacteria (Lactobacillus cereus and Staphylococcus aureus) and gramnegative bacteria (Escherichia coli and Staphylococcus enterica ser. Typhimurium) in a broth microdilution test. The ethanolic extract (EE) are rich in antioxidant-rich phenolic compounds show minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) for every given bacterium on beetroot and spinach leaves. Results: We investigate this extract’s total phenol, total flavonoid, and antioxidant and antibacterial properties. We also identify its main phenolic components, revealing its phytochemical diversity. We found that the EE had 39.29 gGAkg-1 dw of phenol and 96.05 gQE kg-1 dw of flavonoids. The EE scavenges DPPH, H2O2, FRAP, and PM radicals at 142, 168, 275, and 172 g TE kg-1, respectively. We reveal the complex character of this extract by revealing catechins, flavonoids, tannins, malic acid, enzymes, resveratrol, phenolic acids, flavonols, procyanidins, and anthocyanins. Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus are all inhibited by EE with a MIC range of 16 to 18 gL-1 (E. coli). The extract affects bacterial growth at different stages. The EE reduces spinach and beetroot leaf total bacterial load by 1.159 to 2.456 log drop when used as a sanitizer at 25 gL-1 (1.156–2.858 log reduction). Conclusion: This research work highlights grape leaf EE as a novel and appealing source of bioactive components with its strong antibacterial and antioxidant activities against common foodborne infectious agents. Our research reveals that leaf ethanolic extract could reduce human pathogenic microorganisms in fresh green vegetables, improving food safety.

An In-vitro Antioxidant and Antimicrobial Activity of Vitis vinifera Leaf Extract

Background: Vitis vinifera (Flame red grape) is known for its hepatoprotective, nephroprotective and cardioprotective activity of ethanolic and aqueous extracts of aerial parts has been reported but, due to presence of polyphenols, glycosides, saponins and alkaloid, the antioxidant and antimicrobial activity yet not to evaluated on salad plant and bacteria, respectively. Aim: This research examined grape (V. vinifera flaming red) leaf ethanolic extract (EE) as a bioactive resource. Methods: Ethanolic extract test, primarily to calculate the overall phenolic content by using the Folin-Ciocalteu technique and gallic acid taking as a reference. Similarly, flavonoid content measured using quercetin as a calibration curve. Antioxidant properties was confirmed by getting positive responses from different methods (DPPH, H2O2, FRAP and Phospho-Molybdenum). Antimicrobial activity tested against gram-positive bacteria (Lactobacillus cereus and Staphylococcus aureus) and gramnegative bacteria (Escherichia coli and Staphylococcus enterica ser. Typhimurium) in a broth microdilution test. The ethanolic extract (EE) are rich in antioxidant-rich phenolic compounds show minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) for every given bacterium on beetroot and spinach leaves. Results: We investigate this extract’s total phenol, total flavonoid, and antioxidant and antibacterial properties. We also identify its main phenolic components, revealing its phytochemical diversity. We found that the EE had 39.29 gGAkg-1 dw of phenol and 96.05 gQE kg-1 dw of flavonoids. The EE scavenges DPPH, H2O2, FRAP, and PM radicals at 142, 168, 275, and 172 g TE kg-1, respectively. We reveal the complex character of this extract by revealing catechins, flavonoids, tannins, malic acid, enzymes, resveratrol, phenolic acids, flavonols, procyanidins, and anthocyanins. Salmonella enterica subsp. enterica serovar Typhimurium, Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus are all inhibited by EE with a MIC range of 16 to 18 gL-1 (E. coli). The extract affects bacterial growth at different stages. The EE reduces spinach and beetroot leaf total bacterial load by 1.159 to 2.456 log drop when used as a sanitizer at 25 gL-1 (1.156–2.858 log reduction). Conclusion: This research work highlights grape leaf EE as a novel and appealing source of bioactive components with its strong antibacterial and antioxidant activities against common foodborne infectious agents. Our research reveals that leaf ethanolic extract could reduce human pathogenic microorganisms in fresh green vegetables, improving food safety.

The Diels-Alder Cross-Linked Gelatin/Dextran Nanocomposite Hydrogels with Silver Nanoparticles for Wound Healing Applications: Synthesis, Characterization, and In Vitro Evaluation.

Wound healing involves a sophisticated biological process that relies on ideal conditions to advance through various stages of repair. Modern wound dressings are designed to imitate the natural surroundings around cells and offer properties such as moisture regulation, strength, and antimicrobial defense to boost healing. A recent research project unveiled a new type of gelatin (Gel)/dextran (Dex) hydrogels, linked through Diels-Alder (D-A) reactions, loaded with silver nanoparticles (Ag-NPs) for cutting-edge wound treatment. Gel and Dex were chemically modified to form the hydrogels via the D-A reaction. The hydrogels were enriched with Ag-NPs at varying levels. Thorough analyses of the hydrogels using methods like NMR, FT-IR, and SEM were carried out to assess their structure and nanoparticle integration. Rheological tests displayed that the hydrogels had favorable mechanical attributes, particularly when Ag-NPs were included. The hydrogels demonstrated controlled swelling, responsiveness to pH changes, and were non-toxic. Testing against E. coli showcased the strong antibacterial activity of the nanocomposite hydrogels in a concentration-dependent manner. This investigation showcased the promise of these bioactive nanocomposite hydrogels in promoting speedy wound healing by maintaining a moist environment, offering an antimicrobial shield, and ensuring mechanical support at the wound site.

In-situ synthesis of zinc oxide-tannic acid-waste bagasse with antibacterial activity as multifunctional additive for packaging film

The resource utilization of waste bagasse (SB) is a green and effective solution to reduce environmental pollution. However, traditional methods for recycling of bagasse have the technical bottlenecks, including, secondary pollution, low efficiency, high cost and small production scale. Here, we develop a novel mechanical activation technology to convert SB in situ into zinc oxide-tannic acid-SB (ZnO-TA-SB) with antibacterial activity as multifunctional additives for packaging films. Unlike traditional methods that demand harsh reaction conditions, this novel strategy for the resource utilization of SB is convenient, green, efficient and large-scale. The results show that the bactericidal activities of ZnO-TA-SB against E. coli and S. aureus are > 99 %, confirming the strong spectral antibacterial activity of ZnO-TA-SB. With the addition of ZnO-TA-SB to carboxymethyl cellulose (CMC) film, the tensile strength, elongation at break, O2 barrier property of ZnO-TA-SB/CMC film are increased by 1.43, 2.49, 2.09 times compared with CMC film, respectively. Furthermore, ZnO-TA-SB/CMC film effectively keeps the appearance and freshness of strawberries for more than 18 days. Notably, ZnO-TA-SB/CMC film is easily degraded in soil and used as a nutrient for crop growth without secondly pollution. Therefore, this work develops a new strategy for the resource utilization of waste biomass, and obtains green, clean and high-value products from waste biomass.

Green Biosynthesis of Silver Nanoparticles Utilizing Monstera deliciosa Leaf Extract and Estimation of its Antimicrobial Characteristics

AbstractHerein, single step biosynthesis of silver nanoparticles (AgNPs) is reported by using AgNO3 and Monstera deliciosa (MD) leaf extract. Spherical AgNPs are obtained with difference in particle sizes and antibacterial activities using two sets of MD leaf extract having different heating periods 5 and 10 min. They are characterized by UV–vis spectroscopy, X‐ray diffraction (XRD), Zeta potential, Attenuated Total Reflectance Infrared Spectroscopy (ATR‐IR), and Field Emission Scanning Electron Microscopy (FE‐SEM). Dynamic Light Scattering (DLS) studies propose two types of AgNPs have hydrodynamic diameters of 104 and 80 nm. Nuclear Magnetic Resonance (NMR), Gas Chromatography‐Mass Spectrometry (GC‐MS), and High Resolution−Mass Spectrometry (HR‐MS) studies, which reveal the presence of various phytochemicals found in MD leaf extract. These biomolecules play a vital role as stabilizing and reducing agents to fabricate stable AgNPs. These AgNPs exhibit strong antibacterial activities having effective zone of inhibition for both Gram‐positive (Staphylococcus aureus, Bacillus subtilis) and Gram‐negative (Escherichia coli, Pseudomonas aeruginosa) microorganisms, nonetheless AgNPs against different fungi (Penicillium sp., Aspergillus flavus, Fusarium oxysporum, Rhizoctonia solani) show non‐antifungal characteristics because of their inert nature. This study suggests that AgNPs can be used in treating bacterial infections and drug delivery also for several therapeutic and diagnostic applications.

Green Biosynthesis of TiO2 Nanoparticles Using Aqueous Extract of Brassica juncea (L.) Czern Seed: Characterization, Antimicrobial, Antioxidant and Anticancer Activities

AbstractPrimary objective of this research was to examine the biogenic production of TiO2 NPs using Brassica juncea (L.) Czern seed and investigate the prospective uses of thus synthesized nanoparticles in the area of biomedicine. The synthesized TiO2 NPs were subjected to characterization using several analytical methods namely TEM, UV‐vis, XRD, FE‐SEM, FTIR and EDAX. The average particle size (TEM) is found to be 38 nm, exhibiting irregular shapes. The FT‐IR spectra indicated that the extract contains functional groups, such as polyphenolic, hydroxyl and carboxylic groups, which are likely responsible for formation of nanoparticles. The cytotoxicity studies of the synthesized TiO2 NPs against breast cancer cells (MCF‐7) and lung cells (A549) are shown to be dosage dependent. The inhibitory doses (IC50) were determined to be 43.98 μg/mL and 74.50 μg/mL on MCF‐7 and A549 cells, respectively. Green synthesized TiO2 NPs were assessed for antioxidant activity inhibition rate (DPPH 89.42 %). TiO2 NPs exhibited a maximal zone of inhibition of Staphylococcus aureus 23±0.20 mm against and 20±0.30 against Klebsiella pneumoniae at a concentration of 100 μg/mL, indicating strong antibacterial activity. The findings suggest Brassica juncea (L.) Czern seed encapsulated TiO2 NPs possesses excellent biological applications which can be explored for its application in pharmaceutical field.