Superior Antibacterial Activity Research Articles

Evaluating Antioxidant Performance, Biosafety, and Antimicrobial Efficacy of Houttuynia cordata Extract and Microwave-Assisted Synthesis of Biogenic Silver Nano-Antibiotics.

From the traditional Chinese medicine point of view, although Houttuynia cordata extract (HCE) possesses an incredible amount of phytonutrients and exhibits antioxidant activities, excessive doses of HCE can cause danger to organisms and lead to death. In this study, we first examine HCE's overall phenolic and flavonoid content, antioxidant efficacy, and antibacterial activity. Results show that HCE is suitable as a bio-reducing agent for the microwave-assisted synthesis of silver nanoparticles (HCE-AgNPs) with enhanced antioxidant and antimicrobial performance. Under an optimized microwave condition (i.e., 100 °C for 10 min), the HCE-stabilized AgNPs were confirmed with a UV-visible peak at 430 nm and 19.7 ± 4.2 nm in size. Physicochemical properties of HCE-AgNPs were extensively characterized by zeta-potential, FT-IR, XRD, and XPS measurements. Compared to the HC extract counterpart, HCE-AgNPs display superior antioxidant activity, higher DPPH scavenging efficiency, and enhanced broad-spectrum bactericidal activity to inhibit the growth of all tested bacterial strains at doses of 2 μg/mL. Biosafety evaluation indicated that HCE-AgNPs are noncytotoxic on human red blood cells. These data show that the microwave synthesis of AgNPs exhibits a great antioxidant ability, superior antibacterial activity, and a trivial hemolytic effect, providing another bactericidal therapy strategy to address the increasing healthcare-associated infections.

Green synthesis of copper nanoparticles from agro-waste garlic husk

Abstract The objective of this study was to test the antibacterial activity of copper nanoparticles (Cu NPs) against bacterial pathogens by green synthesizing them from aqueous extracts of garlic husk. The synthesized Cu NPs were examined by UV-visible (UV-VIS) spectroscopy at (200–400 nm), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, transmission electron microscopy (TEM), and zeta potential analysis. The findings supported the capping, reduction, and production of Cu NPs with an average crystalline size of 14 nm in the husk extract. The minimum inhibitory concentration technique (MIC test) was used to measure the antibacterial activity against Gram-positive (Escherichia coli, Vibrio cholera) and Gram-negative (Bacillus cereus, Staphylococcus aureus) microorganisms. The lowest concentration required for inhibiting the growth of the bacterial strains ranged from 34.7 to 43.04 μg/ml. The above findings suggest that greenly synthesized Cu NPs made from garlic agro-waste may have potential uses in the realm of nanomedicine as an antibacterial drug in the treatment and prevention of bacterial infections due to their superior antibacterial activity.

Synergistic improvement of antioxidant and antibacterial properties of carbon quantum complexes with zinc doping and chlorogenic acid for longan preservation

The deterioration of fruit could reduce the shelf life, decreased marketability and substantial economic value. Thus, a safe, simple, economical and environmentally friendly preservation technology for fruit is of great significance. Here, the postharvest preservation technology was investigated with zinc-doped carbon quantum dots and chlorogenic acid (Zn-CQDs/CGA) composite. Zn-CQDs/CGA composite were synthesized, which exhibits superior antioxidant and antibacterial activities. The binding mechanism of the Zn-CQDs/CGA composite was investigated, which revealed that the bindings of two components were mainly driven by hydrogen bonding and van der Waals forces to create a novel composite. The Zn-CQDs/CGA composite was applied to longan preservation and was found to significantly reduce the incidence of mildew spot, browning of fruit endocarp and pulp, as well as the degree of degradation of quality indexes. These results suggest that the Zn-CQDs/CGA composite has the potential for inhibiting browning and preserving the quality of longan during storage.

Synthesis and Antibacterial Activity of Novel Triazolo[4,3-a]pyrazine Derivatives

Infectious diseases pose a major challenge to human health, and there is an urgent need to develop new antimicrobial agents with excellent antibacterial activity. A series of novel triazolo[4,3-a]pyrazine derivatives were synthesized and their structures were characterized using various techniques, such as melting point, 1H and 13C nuclear magnetic resonance spectroscopy, mass spectrometry, and elemental analysis. All the synthesized compounds were evaluated for in vitro antibacterial activity using the microbroth dilution method. Among all the tested compounds, some showed moderate to good antibacterial activities against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli strains. In particular, compound 2e exhibited superior antibacterial activities (MICs: 32 μg/mL against Staphylococcus aureus and 16 μg/mL against Escherichia coli), which was comparable to the first-line antibacterial agent ampicillin. In addition, the structure–activity relationship of the triazolo[4,3-a]pyrazine derivatives was preliminarily investigated.

Biosynthesis of Peptide Hydrogel-Titania Nanoparticle Composites with Antibacterial Properties.

The photoantibacterial properties of titania nanoparticles (TiO2NPs) are attracting much interest, but the separation of their suspension limits their application. In this study, the encapsulation of commercial TiO2NPs within self-assembling tripeptide hydrogels to form hgel-TiO2NP composites with significant photoantibacterial properties is reported. The Fmoc-Phe3 hydrogelator was synthesized via an enzymatic method. The resulting composite was characterized with DLS, ζ-potential, SAXS, FESEM-EDS and rheological measurements. Two different concentrations of TiO2NPs were used. The results showed that, by increasing the TiO2NP quantity from 5 to 10 mg, the value of the elastic modulus doubled, while the swelling ratio decreased from 63.6 to 45.5%. The antimicrobial efficacy of hgel-TiO2NPs was tested against a laboratory Staphylococcus aureus (S. aureus) strain and two methicillin-resistant S. aureus (MRSA) clinical isolates. Results highlighted a concentration-dependent superior antibacterial activity of hgel-TiO2NPs over TiO2NPs in the dark and after UV photoactivation. Notably, UV light exposure substantially increased the biocidal action of hgel-TiO2NPs compared to TiO2NPs. Surprisingly, in the absence of UV light, both composites significantly increased S. aureus growth relative to control groups. These findings support the role of hgel-TiO2NPs as promising biocidal agents in clinical and sanitation contexts. However, they also signal concerns about TiO2NP exposure influencing S. aureus virulence.

Levofloxacin-Fatty Acid Systems: Dual Enhancement Through Deep Eutectic Formation and Solubilization for Pharmaceutical Potential and Antibacterial Activity.

Fatty acids, including medium-chain saturated and polyunsaturated fatty acids, are known for their broad health benefits, including antimicrobial activity. Through their green properties, deep eutectic systems have been heralded as having the potential to be at the forefront of pharmaceutical applications. In this work, capric acid and geranic acid, two examples of medium-chain saturated and polyunsaturated fatty acids, were employed to enhance the pharmaceutical properties and the antibacterial activity of levofloxacin. To this end, levofloxacin formulations with either capric or geranic acid were prepared and characterized using appropriate techniques. Levofloxacin was utilized to create innovative deep eutectic systems in conjunction with capric acid at three different molar ratios: 1:9, 2:8 and 3:7. This was confirmed through a rigorous analysis involving nuclear magnetic resonance, infrared spectroscopy and differential scanning calorimetry. Furthermore, it is noteworthy that geranic acid demonstrated an impressive threefold improvement in levofloxacin's solubility compared to its solubility in aqueous solutions. The antibacterial activity of the novel combinations of levofloxacin with either fatty acid was evaluated using a checkerboard titration assay. Gratifyingly, both formulations exhibited synergistic effects against a panel of levofloxacin-sensitive and resistant Gram-negative bacteria. In conclusion, the observed superior antibacterial activity of levofloxacin illuminates the potential use of fatty acid-based formulations and deep eutectic systems as green and innovative strategies to combat the global antimicrobial resistance problem.

Green synthesis of chromium oxide nanoparticles for anticancer, antioxidant and antibacterial activities

Green synthesis of nanoparticles using plants has become a promising substitute for conventional chemical synthesis methods. This study aimed to produce chromium oxide nanoparticles (Cr2O3NPs) utilising lemon juice extract. The production of Cr2O3NPs was characterised using field emission scanning electron microscopy, transmission, X-ray diffraction, electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared, and ultraviolet–visible spectroscopy. The anticancer activity of Cr2O3NPs was determined against lung cancer cell line A549. The antioxidant activity was investigated in the ascorbic acid system. The antibacterial activity of the green synthesised nanoparticles was evaluated against two different bacterial strains, Streptococcus mutans and Escherichia coli. The anticancer activity of synthesised Cr2O3NPs at (6.25, 12.5, 25, 50, and 100) μg/mL against A549 cancer cells was substantial, with more than 70 % of cells cytotoxicity. While, Cr2O3NPs at (55, 62.8, 73.3, 88, and 110) μg/mL as antioxidant agents ascorbic acid system increases, the percentage of the inhibitor capacity by 29.5 %, 30.7 %, 34.5 %, 38.2 %, and 40.4 %, respectively. Finally, Cr2O3NPs at 100 μg/mL exhibit superior antibacterial activity against both Gram-negative bacteria within an inhibition range of 21 and 22 mm respectively.

Selected flavonoids exhibit antibiofilm and antibacterial effects against Vibrio by disrupting membrane integrity, virulence and metabolic activities

Vibrio parahaemolyticus is a high-risk foodborne pathogen associated with raw or undercooked seafoods and its biofilm forming potential has become a threat to food safety and economic values. Hence, this study aims to examine the antibacterial and antibiofilm activities as well as virulence inhibitory effects of selected flavonoids against V. parahaemolyticus. Out of the sixteen flavonoid derivatives, 6-aminoflavone (6-AF), 3,2-dihydroxyflavone (3,2-DHF) and 2,2-dihydroxy-4-methoxybenzophenone (DHMB) were found as active biofilm inhibitors. 3,2-DHF and DHMB had minimum inhibitory concentrations of 20 and 50 μg/mL respectively against Vibrio planktonic cells and displayed superior antibacterial activities to standard controls. Also, they disrupted preformed biofilms and suppressed virulence properties including motilities, cell hydrophobicity and aggregation. They impaired iron acquisition mechanism and hemolysin production at sub-MICs as supported by transcriptomic studies. Interestingly, the flavonoids interfered with the metabolic activity, cell division and membrane permeability to exert antibiofilm and antibacterial activities. 6-AF and 3,2-DHF were non-toxic in the C. elegans model and showed excellent capacity to protect shrimps from biodeterioration. Furthermore, the flavonoids inhibited biofilm formation by V. harveyi, Staphylococcus aureus and Salmonella typhimurium and the mixed-species biofilm with Vibrio. This study discovered flavonoid derivatives, especially 3,2-DHF as potential bioactive compounds capable of offering protection from risks associated with biofilm formation by V. parahaemolyticus and other food pathogens.

Biosynthesis of CaO nanorods and evaluation of their activity as anticancer, antioxidant and antibacterial agents

The unique catalytic and biological properties of CaO nanorods (CaONRs) are greatly influenced by their surface morphology. In this study, CaONRs were synthesised with lemon juice through a green chemistry method. The characteristics of 35–57 nm CaONRs were investigated using transmission electron microscopy, X-ray diffraction, UV–Visible spectroscopy, energy-dispersive X-ray analysis, field emission scanning electron microscopy, and Fourier transform infrared. The antibacterial activity of the green synthesised nanorods was evaluated against two different bacterial strains, Streptococcus mutans and Escherichia coli. The anticancer activity of these nanorods against the A549 lung cancer cell line was also determined. In addition, antioxidant activity was investigated in the ascorbic acid system. The results demonstrated that the green synthesised CaONRs exhibited superior antibacterial activity against both Gram-positive and Gram-negative bacteria within an inhibition range of 21 and 22 mm compared to tetracycline 4 ± 0.25 mm and 10 ± 0.3 mm respectively. The cytotoxicity of CaONRs shows high cytotoxicity values at concentrations of 50 µg/mL and 100 µg/mL compared to cis-platin. The results show there is no significant influence of CaONRs in 100 µg/mL of the BEAS-2B cell line, while 104.7 μg/mL of CaONRs as antioxidant agents increased the cytostatic capacity 52.5 %. Our results suggested that green-synthesised CaONRs could be promising candidates for future biomedical applications.

A quantitative method for determination of colistin E2 methanesulphonate in human plasma by 15N-labeled colistin E2

The single-component colistin E2, with superior antibacterial activity and lower toxicity, was being developed as the latest generation of polymyxin drugs. However, colistin E2 has not been tested quantitatively in biological matrices. In this study, based on the quantitative detection of colistin methanesulphonate (CMS) and colistin by Zhao et al., 15N-labeled colistin E2 was used as an internal standard (IS) for a more accurate quantitative detection of CMS E2 in human plasma. A rapid ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) assay method was developed for determination of CMS E2 and colistin E2 in human plasma. After pretreatment of plasma samples by 96-well SPE Supra-Clean Weak Cation Exchange (WCX) plate, the formed colistin E2 was detected and quantified by UHPLC–MS/MS system. All plasma lots were found to be free of interferences with the analyte. The matrix has no effect on the quantitation of the analyte. No significant effect of the carryover was observed. The dilution integrity was demonstrated in plasma samples without the loss of accuracy and precision. The lower limit of quantification (LLOQ) was 0.0300 mg/L for colistin E2 in plasma with accuracy (relative error, 5.1–12.7%) and precision (relative standard deviation, − 5.7–9.3%). Stability of CMS E2 and colistin E2 was demonstrated in biological samples before and during sample treatment, and in the extract. Furthermore, this method was successfully applied to the analysis of plasma samples obtained from Chinese healthy volunteers receiving a single intravenous CMS E2 dose of 5 mg/kg. In conclusion, the detection method was characterized by speed and high accuracy, which laid a solid foundation for the subsequent development of CMS E2 drug.

Solvent based fractional biosynthesis, phytochemical analysis, and biological activity of silver nanoparticles obtained from the extract of Salvia moorcroftiana.

Multi-drug resistant bacteria sometimes known as "superbugs" developed through overuse and misuse of antibiotics are determined to be sensitive to small concentrations of silver nanoparticles. Various methods and sources are under investigation for the safe and efficient synthesis of silver nanoparticles having effective antibacterial activity even at low concentrations. We used a medicinal plant named Salvia moorcroftiana to extract phytochemicals with antibacterial, antioxidant, and reducing properties. Three types of solvents; from polar to nonpolar, i.e., water, dimethyl sulfoxide (DMSO), and hexane, were used to extract the plant as a whole and as well as in fractions. The biosynthesized silver nanoparticles in all extracts (except hexane-based extract) were spherical, smaller than 20 nm, polydispersed (PDI ranging between 0.2 and 0.5), and stable with repulsive force of action (average zeta value = -18.55±1.17). The tested bacterial strains i.e., Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis were found to be sensitive to even small concentrations of Ag-NPs, especially P. aeruginosa. The antibacterial effect of these Ag-NPs was associated with their ability to generate reactive oxygen species. DMSO (in fraction) could efficiently extract antibacterial phytochemicals and showed activity against MDR bacteria (inhibition zone = 11-12 mm). Thus, the antibacterial activity of fractionated DMSO extract was comparable to that of Ag-NPs because it contained phytochemicals having solid antibacterial potential. Furthermore, Ag-NPs synthesized from this extract owned superior antibacterial activity. However, whole aqueous extract-based Ag-NPs MIC was least (7-32 μg/mL) as compared to others.

Exploring diaminomaleonitrile-derived Schiff base ligand and its complexes: Synthesis, characterization, computational insights, biological assessment, and molecular docking

A tetra dentate ONNO donor diaminomaleonitrile-based Schiff base ligand along with its four new complexes of Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized. The computational approach has been utilized to provide a theoretical framework for understanding the electronic structure and properties of these complexes. The distorted octahedral geometry of the Schiff base metal complexes indicates that the metal ions are coordinated with the ligand through ONNO donor sites, which is further confirmed by characterization using physiochemical and spectroscopic techniques like elemental analysis, mass, electronic, infrared, 1H, and 13C spectra. In addition, magnetic behavior is analyzed using the Vibrating Sample Magnetometer(VSM). To evaluate the potential modes of biomolecular interactions with the synthesized complexes utilizing Deoxyribo Nucleic Acid(DNA) and to assess the corresponding binding constants, an absorption spectroscopic technique has been utilized. Metal complexes are reported to have a range of binding constant values from 5.45 × 104 M−1 to 4.35 × 105 M−1 with different binding modes, such as intercalation, mixed mode, and electrostatic contact. In addition, in-vitro tests for antibacterial and anti-inflammatory activity have been employed to assess the bioactivities. With an IC50 value of 209.24 µg/mL, the Zn(II) complex is found to show considerable anti-inflammatory action as well as has superior antibacterial activity among all other complexes. The existence of electron-withdrawing CN groups together with other factors can be accounted for biological activity in our reported complexes. Further, molecular docking simulations are conducted to gain insights into the molecular-level interactions and to determine the potential binding energies of inhibitors whose results are in consistent with the in-vitro investigations.

Synergistic enhancement of photocatalytic and antimicrobial efficacy of nitrogen and erbium co-doped ZnO nanoparticles

Using the chemical co-precipitation approach, a series of nitrogen (N) and erbium (Er) co-doped ZnO nanoparticles (NPs) was effectively synthesized to enhance the photocatalytic and antibacterial activities. Several characterization techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), UV-vis, and photoluminescence (PL) spectroscopy, were carried out to validate the evaluated photocatalytic and antibacterial activities. XRD analysis confirms the pure wurtzite ZnO phase without the presence of any secondary phase. XPS analysis confirms the successful incorporation of nitrogen and erbium into the ZnO matrix. The optical bandgap of ZnO calculated from UV-vis spectroscopy shows a redshift after Er–N co-doping, with the lowest bandgap of 3.215 eV calculated for Zn0.97Er0.03N0.01O0.99 NPs. SEM images demonstrate the formation of nanorods after N–Er co-doping, followed by gradually increased rod diameter and length after N–Er co-doping. Moreover, the photocatalytic activities of ZnO samples were measured by their ability to facilitate the photodegradation of Rhodamine B under UV irradiation. ZnO with 1 mol% N doping exhibits 88% photodegradation of RhB under UV light within 360 min, and the photodegradation and antibacterial activity are greatly improved with Er co-doping. In fact, 3 mol% Er-1 mol% N doped ZnO NPs demonstrate the highest photocatalytic activity, with approximately 96% degradation after 360 min, as well as superior antibacterial activity against Staphylococcus aureus (Gram-positive bacteria) and Pseudomonas aeruginosa (Gram-negative bacteria) with the highest zone of inhibition (ZOI) of 16 nm, due to nanorod formation, increased reactive oxygen species (ROS), and decreased electron–hole recombination, as validated by SEM, XPS, and PL spectroscopy.

Green synthesized clavate-shaped ZnO modified silk fabric with aging resistance and outstanding antibacterial and UV-shielding properties

Silk, a popular luxury textile with many years of history, is easy to embrittle and adsorb bacteria when stored for a long time or exposed to sunlight, which affects its service life. To improve the silk fabrics with excellent antibacterial activity, washing and aging durability, and UV shielding, multifunctional silk fabrics were designed and fabricated via a green finishing approach. Here, we proposed a simple strategy to fabricate silk fabrics with multi-functions via coating clavate-shaped ZnO nanoparticles (ZF-silk fabrics) by dipping and pressing for cycles. The scanning electron microscope (SEM), fourier transform infrared (FTIR), ultraviolet visible spectrophotometry (UV–Vis), and X-ray diffraction (XRD) were used to analyze the structure and properties of fabricated ZF-silk fabrics. Compared with raw silk fabric, the fabricated ZF-silk fabrics represented excellent UV shielding, good tensile strength, and superior antibacterial activity. Notably, the ZF-silk fabrics had good washing stability and aging resistance. In addition, the ZF-silk fabrics possessed superior antibacterial activity before and after aging treatment (under UV radiation for 72 h). Therefore, the durable and multifunctional ZF-silk fabrics indicate great potential for achieving to realize a long service life of the fabrics.

Mixed Ligand Complexes of Ni2+, Cu2+ and Zn2+ Ions Containing N-(4-methoxybenzylidene)isonicotinohydrazone Schiff Base and 1,10-Phenanthroline : Synthesis, Characterization, Antimicrobial and Antioxidant Properties

N-(4-methoxybenzylidene) isonicotinohydrazone (L1) Schiff base ligand was prepared by the condensation reaction of isonicotinic acid hydrazide (INH) and 4-methoxybenzaldehyde. A series of metal complexes of Ni2+, Cu2+ and Zn2+ ions was synthesized with Schiff base ligand (primary ligand, L1) and 1, 10-phenanthroline (L2) as a secondary ligand in stoichiometry ratio (1:1:1). Moreover, the synthesized ligand and its complexes have been characterized by analytical and physical properties, conductivity, magnetic susceptibility measurements, FTIR-spectra, and UV-Visible spectra. Conductivity measurements indicated that all complexes were 1:2 electrolytic in nature. IR spectra recommended that the oxygen of the carbonyl group (=CO) and nitrogen of the azomethine group (-C=N) were coordinated with metal ions. The confirmation of a square planar structure for Ni2+ and Cu2+ complexes, as well as a tetrahedral structure for the Zn2+ ion complex, was supported by their respective magnetic moment values and UV-Visible spectra. The antimicrobial activity of the metal complexes formed by L1 and L2 was evaluated against Escherichia coli and Pseudomonas sp. The metal complexes formed by the combination of L1 and L2 were subjected to testing against Escherichia coli and Pseudomonas sp. The Zn(II) complex exhibited superior antibacterial activity compared to the reference drug Kanamycin-30 against both bacterial strains in the tested compounds. In addition, the synthesised metal complexes demonstrated a comparatively moderate level of antioxidant activity when compared to the Schiff base. The Cu2+-complex exhibited the highest level of activity, while the Zn2+ -complex demonstrated the lowest antioxidant activity, which was comparable to that of BHT.

Real-time in vivo monitoring of the antimicrobial action of combination therapies in the management of infected topical wounds

The increasing prevalence of non-healing infected wounds has become a serious concern in the clinical practice, being associated to population aging and to the rising prevalence of several chronic conditions such as diabetes. Herein, the evaluation of the bactericidal and antibiofilm effects of the natural antiseptic terpenes thymol and farnesol standing alone or in combination with the standard care antiseptic chlorhexidine was carried out both in vitro and in vivo. The in vitro combinatorial treatment of chlorhexidine associated with those terpenes against Staphylococcus aureus in its planktonic and sessile forms demonstrated a superior antibacterial activity than that of chlorhexidine alone. Real-time in vivo monitoring of infection progression and antimicrobial treatment outcomes were evaluated using the bioluminescent S. aureus strain Xen36. In vivo studies on infected wound splinting murine models corroborated the superior bactericidal effects of the combinatorial treatments here proposed. Moreover, the encapsulation of thymol in electrospun Eudragit® S100 (i.e., a synthetic anionic copolymer of methacrylic acid and ethyl acrylate)-based wound dressings was also carried out in order to design efficient antimicrobial wound dressings.

Optimizing extraction of Pelargonium sidoides roots: Impact of ethanol concentration on biological activity of extracts

Pelargonium sidoides DC. (Geraniaceae) is an important indigenous medicinal plant in South Africa, historically employed by various ethnic groups to treat respiratory and gastrointestinal ailments. The proprietary herbal tincture, Umckaloabo®, utilizes an ethanolic extract (EPs® 7630) from the roots of P. sidoides, and has demonstrated effectiveness in alleviating symptoms of respiratory infections.P. sidoides roots contain numerous highly oxygenated coumarins and phenolic metabolites, notably the marker compound umckalin. While Umckaloabo® is prepared using 11 % ethanol extraction, the South African commercial market predominantly employs 60 % ethanol extraction due to its consistent umckalin yield and antimicrobial activity. The effects of these extraction methods on chemical composition and in vitro pharmacological activity remain poorly understood.This study confirmed superior antibacterial and antifungal activity in the 60 % ethanol extracts prepared from six root samples compared to the 11 % ethanol extracts. MIC values for both Gram-negative and Gram-positive bacteria ranged from 0.078 to 2.5 mg/mL in the 60 % extracts. Remarkably, two of the root extracts exhibited excellent to very good activity against C. albicans and C. neoformans with MIC values of 0.039 and 0.078 mg/mL, respectively.A positive correlation was identified between total minimum inhibitory concentration (MIC) levels and polyphenol content, rather than umckalin levels. The influence of these extracts on the pro-inflammatory cytokine IL-6 was assessed. Both 60 % and 11 % root extracts of P. sidoides at 100 µg/mL significantly reduced IL-6 production, with the 60 % extracts demonstrating a more pronounced effect (p = 0.008).Statistical analysis revealed significant differences between 11 % and 60 % ethanol extractions in terms of average MIC overall, average Gram-negative MIC, average Gram-positive MIC, fungal MIC, and IL-6 levels. Extracts with higher polyphenol values exhibited superior antimicrobial activity and antioxidant potential, suggesting that polyphenol content may serve as a more reliable indicator of antimicrobial activity than umckalin levels. Additionally, polyphenol levels in the roots may vary with altitude and other environmental factors, warranting further research.

Synthesis of novel antibacterial and biocompatible polymer nanocomposite based on polysaccharide gum hydrogels

According to recent studies on the benefits of natural polymer-based hydrogels in biomedical applications, gellan gum (GG)/acacia gum (AG) hydrogel was prepared in this study. In order to regulate the mechanical behavior of the hydrogel, graphite carbon nitride (g-C3N4) was included in the hydrogel matrix. In addition, metal oxide nanoparticles ZnCuFe2O4 were added to the composite for antibacterial activity. The prepared GG–AG hydrogel/g-C3N4/ZnCuFe2O4 nanobiocomposite was characterized by using FE-SEM, FTIR, EDX, XRD and TGA. The nanobiocomposite exhibited spherical morphology, which was related to the incorporation of the metal oxide nanoparticles. GG–AG hydrogel/g-C3N4/ZnCuFe2O4 nanobiocomposite showed 95.11%, 92.73% and 88.97% biocompatibility toward HEK293T cell lines within 24 h, 48 h and 72 h incubation, respectively, which indicates that this nanobiocomposite is completely biocompatible with healthy cells. Also, the nanobiocomposite was able to inhibit Pseudomonas aeruginosa biofilm growth on its surface up to 87%. Rheological studies showed that the nanobiocomposite has a viscoelastic structure and has a water uptake ratio of 93.2%. In comparison with other similar studies, this nanobiocomposite has exhibited superior antibacterial activity complete biocompatibility and proper mechanical properties, high swelling and water absorption capability. These results indicate that GG–AG hydrogel/g-C3N4/ZnCuFe2O4 nanocomposite can be considered as a potential candidate for biomedical applications such as tissue engineering and wound healing.

Investigation of antimicrobial and physical properties of polyester/cotton blended knitted fabric treated with AgNO3 and aloe vera

The application of antimicrobial textiles is rising rapidly because of their healthcare, comfort, and hygienic attributes. This work aimed to develop an antibacterial polyester/cotton (50/50) blended knitted fabric coated with silver nitrate (AgNO3) and a natural aloe vera gel. In the present investigation, Polyester/Cotton (50/50) blended knitted fabrics have been treated by exhaust method using various concentrations of AgNO3 such as 0.5%, 0.75%, 1.0%, and aloe vera gel 25%, 40%, and 50%, respectively. The antibacterial performance of the coated textiles has been assessed qualitatively against Staphylococcus aureus and Salmonella bacteria by the standard agar diffusion technique (AATCC-147 test method). Furthermore, the effects of AgNO3 and aloe vera have been investigated in terms of tensile strength, elongation at break, and tear strength of the coated textiles. The experimental results showed that both the Aloe vera gel and AgNO3 have significant antibacterial action against Staphylococcus aureus and Salmonella bacteria. However, the blended knitted fabric treated with aloe vera gel showed a superior antibacterial activity against both bacteria than fabric finished with AgNO3. The functional elements of aloe vera and AgNO3 in treated materials were investigated using Fourier transform infrared spectroscopy and the surface morphology is revealed using FESEM. Finally, cost analysis shows that antimicrobial polyester/cotton blended fabrics can be developed with eco-friendly aloe vera at the cheapest cost compared to expensive AgNO3

Eggshell waste act as multifunctional fillers overcoming the restrictions of starch-based films

Starch has great potential to replace petroleum-based plastics in food packaging applications. However, starch films often exhibit poor mechanical and barrier properties, and are vulnerable to moisture and bacterial contamination. This study proved that the incorporation of eggshell powder (ES) enhanced the hydrogen bonding in starch-based films significantly, which contributed to improved tensile strength, Young's modulus, and water resistance of the films. The performance of ES-incorporated films could be optimized by adjusting the size, concentration, and surface property of ES in the film matrix. Notably, adsorbing epigallocatechin gallate (EGCG) on the surface of porous ES contributed to enhanced dispersibility of the fillers in the film matrix, which increased the tortuous path of light, water vapor, and oxygen have to take through the films, resulting in increased UV screening performance, water vapor and oxygen barrier property of the films by 60 %, 7.2 %, and 27.9 %, respectively. Meanwhile, loading EGCG in ES also enable superior antibacterial activity of the final films. This study suggests that eggshell fillers offer a sustainable means of improving the functional performance of starch-based films, which may increase their application as packaging materials in the food industry.