Highest Inhibitory Effect Research Articles

Instant and Synergistic Antibacterial Coating of Silver Loaded With Silica Nanoparticles for Different Applications

ABSTRACTThe synthesis of antibacterial nanoparticles is one of the most promising strategies to get rid of the primary threat that pathogenic bacteria pose to public health. Silver nanoparticles (AgNPs) are a promising antibacterial agent with robust and broad antibacterial characteristics that have the potential to resolve this issue. A straightforward reduction–impregnation approach for creating an Ag‐loaded SiO2 nanocomposite has been presented in the present study. First, the well‐known Stöber method was employed to produce silica nanoparticles, which were subsequently examined utilizing an X‐ray diffraction (XRD), a field emission scanning electron microscope (FE‐SEM), and a high‐resolution transmission electron microscope (HR‐TEM). After that, a composite made of Ag@SiO2 was produced and examined. AgNPs, which are loaded with silica and exhibit instantaneous and synergistic antibacterial activity against Gram‐positive “Bacillus subtilis” (B. subtilis) bacteria, were demonstrated. The coating layer that was produced also showed strong adherence to the steel substrate, a high inhibitory effect against the (B. subtilis), and versatility in its application across various sectors.

Investigation of the Synergistic Effect of Rosehip Vinegar and Propolis Extract on Antibacterial and Antibiofilm Efficacy Against Foodborne Pathogens and Their Protective Effect on Sardine (Sardina pilchardus)

ABSTRACT The antibacterial and antibiofilm effects of rosehip vinegar and propolis extract, separately and as a mixture, were investigated on Staphylococcus aureus and Escherichia coli O157:H7. The organoleptic properties and tissue integrity of sardine fish treated with this mixture were evaluated. The propolis extract was found to have a higher inhibitory effect (>80%) on S. aureus (up to the 5th dilution) than on E. coli O157:H7 (only at the first dilution). A potential synergistic antibacterial and antibiofilm effect of the mixture was observed with an inhibition ratio of ≥50%. This mixture may extend the shelf life of sardines as a natural antibacterial/antibiofilm preservative.

Antiquorum Sensing Effect, Theoretical, and X‐Ray Studies of a Schiff Base Molecule Containing Pyrimidine Nucleus

AbstractCompound 4, a Schiff base‐containing pyrimidine moiety, was synthesized from the reaction of N‐amino pyrimidine derivative with 4‐fluorobenzaldehyde. The molecular and crystallographic structure of 4 was determined by the SC‐XRD method. According to these results, compound 4 crystallized in the triclinic P‐1 space group, and the stability of its crystal structure was ensured through intermolecular C−H⋅⋅⋅π and π⋅⋅⋅π interactions. In addition to the antibacterial effects of the molecule on some Gram‐positive and Gram‐negative bacteria, the inhibition of biofilm formation in P. aeruginosa PAO1 and the production of violacein pigment in Chromobacterium violaceum (C. violaceum) 12472 were studied. The results demonstrated that compound 4 had strong effectiveness in preventing the formation of biofilms produced by PAO1 with an inhibition rate of 69 %. Extensive theoretical calculation studies of molecule have been conducted and the molecular structure of 4 has been optimized in the ground state using density functional theory (DFT). The investigated compound's frontier molecular orbitals, chemical parameters, and molecular electrostatic potential surfaces were examined. Molecular docking studies were performed to explain the binding interaction 4 with the high inhibitory effect against C. violaceum phenylalanine hydroxylase D139A (PDB ID: 4Q3Y), D139E (PDB ID: 4Q3W), D139K (PDB ID: 4Q3Z), and D139N (PDB ID: 4Q3X) mutations.

Impact of Microencapsulation on Ocimum gratissimum L. Essential Oil: Antimicrobial, Antioxidant Activities, and Chemical Composition

Ocimum gratissimum (OG) is a species rich in essential oils (EO), which is known for its antimicrobial and antioxidant properties. This study aimed to encapsulate the essential oil of Ocimum gratissimum (OGE), determine its chemical composition, and evaluate its antioxidant and antimicrobial activities against six pathogenic bacteria, comparing it with the free essential oil (OGF). The EO was extracted by hydrodistillation using a Clevenger-type apparatus, and an oil-in-water emulsion was prepared using a combination of biopolymers: maltodextrin (MA), cashew gum (CG), and inulin (IN). The chemical profile was identified using gas chromatography–mass spectrometry (GC–MS). Antioxidant activity was assessed using the Oxygen Radical Absorbance Capacity with fluorescein (ORAC-FL) method, while the Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) were determined by the microdilution method. Microparticles were formed using the spray-drying method, achieving an encapsulation efficiency of 45.2%. The analysis identified eugenol as the main compound both before and after microencapsulation. The OGE microparticles demonstrated high inhibitory and bactericidal effects against S. aureus, S. choleraesuis, and E. coli, with MIC values of 500 µg·mL−1 and MBC values of 1000 µg·mL−1, as well as antioxidant activity of 1914.0 µmol-TE·g−1. Therefore, it can be inferred that the EO of OG maintained its antimicrobial and antioxidant effects even after microencapsulation by spray-drying, making it a promising natural ingredient.

A square planar cobalt(II)-thiosemicarbazone complex. Synthesis, characterization, antiviral and anti-inflammatory potential

Considering the possible antiviral effect of cobalt compounds and known pharmacological potential of thiosemicarbazones, a new combination containing cobalt(II) ions and tetradentate thiosemicarbazone was synthesized and structurally analyzed. In the complex structure (Co1), the cobalt ion is in 2+ oxidation state and is coordinated with ONNO donor set on the thiosemicarbazone backbone. The complex molecule crystallizes in the space group P21/m and the environment of the cobalt center tends to square planar geometry. The inhibitory performance of SARS-CoV-2 and the anti-inflammatory impact of the complex molecule were investigated. It was found that Co1 has high inhibitory effects on the SARS-CoV-2 virus's 3CL main protease enzyme, ACE2:SARS-CoV2 Spike RBD interaction, and IL8. Also, it showed significant anti-inflammatory effects on the release of IL6, IL8, IL10, and TGFβ1 cytokines and wound healing during in vitro TNF-α-induced inflammation. Experimental evidence demonstrates that Co1 diminishes both IL8 gene expression and protein levels. According to in silico and experimental results, it has a drug potential. Assessing the in vivo impacts of Co1 might contribute to understanding its potential as an antiviral and anti-inflammatory agent.

One-step hydrothermal synthesis of F,N,S-doped photoluminescent carbon dots with yellowish-orange emission for sensitive Cu2+ ion detection: Environmental and biomedical applications

Herein, fluorine-, nitrogen-, and sulfur-doped carbon dots (FNS-CDs) were prepared via a one-step hydrothermal synthesis using flufenamic acid and thiourea as precursors, which showed yellowish-orange fluorescence both in aqueous solution and in the solid state. The as-prepared FNS-CDs were monodisperse and had an average diameter of 4 nm, good water solubility, a fluorescence quantum yield of 18.63 %, and excellent pH and ionic strength stability. The optimal excitation/emission wavelengths of the FNS-CDs were 406/570 nm, with an excitation-dependent wavelength range of 365–435 nm. The surface states, morphologies, and elemental compositions of the FNS-CDs were characterized using FTIR, XRD, TEM, and XPS. In addition, the FNS-CDs without any further modification exhibited high selectivity and sensitivity as nanosensors for Cu2+ over other metal ions. The PL quenching phenomenon can be used to detect Cu2+ ions within a linear range of 1–25 μM with a detection limit of 83.10 nM and an association constant of 1.29 × 104 M−1. The PL of the FNS-CDs was significantly quenched by Cu2+ ions through static quenching and was restored upon the subsequent addition of EDTA. The practical application was demonstrated through the detection of Cu2+ ions in real water samples, yielding recovery rates ranging from 97.8 % to 103.9 % with an RSD below 2.5 %. The FNS-CDs/Cu2+ complex exhibits potent antibacterial activity against S. aureus (85.27 %±2.1 %) and E. coli (91.31 %±1.6 %), whereas the FNS-CDs/Cu2+ has a higher inhibitory effect on the growth of E. coli. Furthermore, the FNS-CDs (100 μg/mL) were used for cell imaging, showing low toxicity to HCT-116 cells exhibited yellowish-orange fluorescence under a confocal microscope.

Silver secnidazole nano-hybrid emulsion-based probiotics as a novel antifungal formula against multidrug-resistant vaginal pathogens.

This study presents a novel approach to manage vaginal infections due to Candidiasis, utilizing a novel silver secnidazole nano-hybrid emulsion (Ag-Secn-NHE)-based probiotics and free Ag-Secn-NHE. Ag-Secn-NHE was prepared by simple homogenization‒ultrasonication technique and validated by using a ultraviolet‒visible scan, dynamic light scattering, transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, and zeta potential. Saccharomyces cerevisiae (RCMB 002Y001) is the most effective probiotic-producing organism that demonstrates significant effects when combined with Ag-Secn-NHE. Ag-Secn-NHE-based probiotics showed significant antifungal effect compared to free Ag-Secn-NHE, silver nitrate, silver nanoparticles, secnidazole, secnidazole nanoemulsion, and commercial vaginal wash against multidrug-resistant vaginal pathogens. The highest inhibitory effect was achieved with Ag-Secn-NHE-based probiotic against Candida auris, Candida albicans, and Cryptococcus neoformans with minimal inhibitory concentration (MIC) 0.625±0.002, 0.00625:1.25±0.012 and 0.00625:1.25±0.032mg/mL, respectively, in comparison with Ag-Secn-NHE that show MIC at 0.00625:1.25±0.612, 0.0125:2.5±0.812, and 0.0125:2.5±0.112mg/mL (Ag:Secn). Ag-Secn-NHE-based- probiotic show minimum fungicidal concentration (MFC) at range from 2.5 to 20mg/mL, wherever free Ag-Secn-NHE show MFC range from 5 to >20mg/mL. Additionally, Ag-Secn-NHE-based probiotics have 75% inhibition of biofilm formation against C. auris and 60% inhibition of biofilm formation against both Cryptococcus neoformans and C. albicans in comparison with free Ag-Secn-NHE. Time-kill curves showed that the antifungal effect of Ag-Secn-NHE-based probiotics was fungistatic at 2MIC value after 4h and after 16h for Ag-Secn-NHE. TEM photographs showed that C. auris cells treated with Ag-Secn-NHE-based probiotic formula revealed severe deformations and distored ultrastructural changes. furthermore, results indicated that the Gamma radiation up to 15kGy increases production of Ag-Secn-NHE in comparison with non-irradiated one.

Phytochemical profiles, bioactivities, and molecular docking and molecular dynamics approaches of endemic Campanula baskilensis Behçet (campanulaceae)

Campanula species have phenolic derivatives with a broad biological potential. This study aimed to investigate the chemical contents, bioactivities, and prediction of the biological effect mechanism using the molecular docking study for C. baskilensis (CB) leaf (L), root (R), and stem (S) extracts.CBL gave the highest phenolic contents as hesperidin at 7.56 mg/g extract. Total phenolic and flavonoid contents of CBS were determined as 3.12 ± 0.05 mg GAE/g and 1.11 ± 0.11 mg QE/g, respectively. CBS and CBL exhibited high DPPH• scavenging, H2O2 scavenging, AChE, BChE, carbonic anhydrase, lipase, and tyrosinase inhibition effects and demonstrated potent antimicrobial activity. The strong phenolic components of CBS and CBL extracts contributed to their biological activities. According to the molecular docking results, a high inhibition effect was observed on the inhibition activities due to the presence of hesperidin, which is the highest main component of the extracts. Additionally, docking studies were performed on hesperidin for the first time. Dynamics study showed that the interaction between the hesperidin and BChE increased stability, producing a stable complex form within 100 ns. In conclusion, C. baskilensis extracts, especially hesperidin, may be promising potential sources for neurological diseases and complementary medicine.

Discovering Novel Bioherbicides: The Impact of Hemp-derived Phytocannabinoid Applications on Zea mays L. and Relevant Weeds

In addition to competition, phytotoxic plant metabolites contribute to the weed-suppressing properties of cover crops, which could be the basis for the development of novel bioherbicides. We investigated the impact of five Cannabis sativa L. -derived neutral phytocannabinoids and an aqueous C. sativa tissue extract (HE) at six concentrations on the germination rate (GR) and seedling root length (RL) of Zea mays L., two monocotyledonous and two dicotyledonous weed species in laboratory Petri dish bioassays. Additionally, the effect of pre-emergence applications of HE, cannabidiol (CBD), and cannabidivarin (CBDV) formulations on GR and shoot dry matter (SDM) were examined in greenhouse pot studies. The effects of phytocannabinoids and HE were analyzed in dose-response curves. For the highest rates, the effects on GR, RL and SDM were calculated by ANOVA and HSD test (p < 0.05). HE exhibited the greatest suppression on GR and RL for all plant species in the Petri dish bioassay, with RGR, RL exceeding −90%. Phytocannabinoids reduced mainly RL of all plants and decreased the GR of most weed species. Effects varied among plants and phytocannabinoids, with CBDV and CBD showing similar high inhibitory effects on RL as HE in the Petri dish bioassay. All pre-emergence applications resulted in a positive RGR across all studied plants and in a positive RSDM in Z. mays and Echinochloa crus-galli (L.) P. Beauv, whereas in the other weed species the RSDM was negative. In conclusion, phytocannabinoids play a major role in weed suppression of HEs. CBDV and CBD are the most promising candidates for bioherbicide development especially against annual dicotyledonous weed species.

Green Biosynthesis and Biological Properties of Copper Oxide Nanoparticles Using Paulownia Tomentosa Plant Extracts

AbstractCopper oxide nanoparticles have attracted a great deal of attention in many fields due to their attractive physico‐chemical properties. In particular, their synthesis using an environmentally friendly method offers advantages in many applications. In the present report, copper oxide nanoparticles are produced from extracts of the plant Paulownia tomentosa by a method of biosynthesis. The synthesized CuO NPs have been characterized morphologically and structurally by fourier transform infrared spectroscopy, scanning electron microscopy, energy‐dispersive X‐ray analysis, and X‐ray diffraction. Furthermore, the antimicrobial, antibiofilm and anticancer activities of the synthesized CuO NPs were evaluated. The CuO NPs were spherical and the particle size was 12.5 nm. For the tested microorganisms, CuO NPs showed a high inhibitory effect in terms of antimicrobial and antibiofilm activity. The cytotoxicity of the synthesized CuO NPs against HT‐22 and MCF‐7 showed a dose‐response activity. 50 % inhibitory concentration values were found to be 18.34 and 14.32 μg/mL of CuO NPs against the HT‐22 and MCF‐7 cancer cells, respectively. The results suggest that these nanoparticles can be used as effective antibacterial, antibiofilm and anticancer agents in the biomedical fields.

Development of fucoidan/polyethyleneimine based sorafenib-loaded self-assembled nanoparticles with machine learning and DoE-ANN implementation: Optimization, characterization, and in-vitro assessment for the anticancer drug delivery

This study aims to develop sorafenib-loaded self-assembled nanoparticles (SFB-SANPs) using the combined approach of artificial neural network and design of experiments (ANN-DoE) and to compare it with other machine learning (ML) models. The central composite design (CCD) and ML algorithms were used to screen the effects of concentrations of both the polymers (polyethyleneimine and fucoidan) on the outcome responses, i.e., particle size and entrapment efficiency with defined constraints. The prediction from different ML models (bootstrap forest, K-nearest neighbors, artificial neural network, generalized regression-lasso and support vector machines) were compared with ANN-DoE model. The ANN-DoE model showed better accuracy and predictability and outperformed all the other models. This depicted that the concept of using ANN and DoE combination approach provided the best, uncomplicated and cost-effective way to optimized the nanoformulations. The optimized formulation generated from the ANN-DoE combined model was further evaluated for characterization and anticancer activity. The optimized SFB-SANPs were prepared using the polyelectrolyte complexation method with Polyethyleneimine (PEI) as a cationic polymer and fucoidan (FCD) as an anionic. The SFB-SANPs were nanometric in size (280.4 ± 0.089 nm) and slightly anionic in nature (zeta potential = −6.03 ± 0.92 mV) with an encapsulation efficiency of 95.56 ± 0.30 %. The drug release from SFB-SANPs was controlled and sustained in the cancer microenvironment (pH 5.0). The SFB-SANPs were compatible with red blood cells (RBCs), and the % hemolysis was found to be <5.0 %. The anticancer activity of the SFB-SANPs exhibited an IC50 at 2.017 ± 0.516 μM against MDMB-231 cells, showing a significantly high inhibitory effect on breast cancer cell lines. Therefore, the nanocarriers developed using various ML tools inherit a huge promise in anticancer drug delivery.

In-vitro Antimicrobial Activity of Mtad, Photoactivated Disinfection Along with Chlorohexidine on Enterococcus faecalis, Staphylococcus aureus and Candida albicans

This study evaluated the antimicrobial activity of five root canal irrigants against MTCC of Enterococcus faecalis, Staphylococcus aureus, Candida albicans, in-vitro study of the inhibitory activity of PAD in conventional Endodontic Treatment (CET) and also combination of CET with PAD (CHX+PAD). All of these microorganisms were incubated in the presence of an Endodontic irrigant. Agar diffusion tests were performed and colony counts were tested using paper point to evaluate the inhibitory effect of the irrigants. The mean diameters of the inhibition zones for C. albican were 21mm 3% Naocl, 19mm CHX, 0.7PAD, 22mm CHX+PAD, 20mm Fluconazole, 18mm Doxycycline. The zone diameters of the inhibition zones of Enterococcus faecalis were 17mm 0.5% Naocl, 18mm CHX, 12mmPAD, 35mm MTAD, and 19mm PAD+CHX. The Zone Diameter of the inhibition zones of Staphylococcus aureus were 18mmCHX, 12mm PAD, 19mm PAD+CHX, 25mm MTAD, and 19mm 3% NaoCl. Together High inhibitory effect was detected for PAD+CHX and MTAD on all three pathogens. Candida showed more inhibition to all irrigants followed by Staphylococcus aureus and Enterococcus faecalis.

Design of new α-glucosidase inhibitors based on the bis-4-hydroxycoumarin skeleton: Synthesis, evaluation, and in silico studies

In this work, we have reported the design, synthesis, in vitro, and in silico enzymatic evaluation of new bis-4-hydroxycoumarin-based phenoxy-1,2,3-triazole-N-phenylacetamide derivatives 5a-m as potent α-glucosidase inhibitors. All the synthesized analogues showed high inhibition effects against α-glucosidase (IC50 values ranging between 6.0 ± 0.2 and 85.4 ± 2.3 µM) as compared to the positive control acarbose (IC50 = 750.0 ± 0.6 µM). Among the newly synthesized compounds 5a-m, 2,4-dichloro-N-phenylacetamide derivative 5i with inhibition effect around 125-folds more than the acarbose was identified as the most potent entry. A structure–activity relationship (SAR) study about the title compounds 5a-m demonstrated that the inhibition effects of these compounds depend on the pattern of substitution on the N-phenylacetamide ring. The interaction modes and binding energies in the active site of enzyme of the important analogues (in term of SAR study) were evaluated through molecular docking study. Molecular dynamics and prediction of pharmacokinetic properties and toxicity of the most potent compound 5i also evaluated and the obtained data was compared with the acarbose.

Inhibitory Effects, Fluorescence Studies, and Molecular Docking Analysis of Some Novel Pyridine-Based Compounds on Mushroom Tyrosinase.

Melanin biosynthesis in different organisms is performed by a tyrosinase action. Excessive enzyme activity and pigment accumulation result in different diseases and disorders including skin cancers, blemishes, and darkening. In fruits and vegetables, it causes unwanted browning of these products and reduces their appearance quality and economic value. Inhibiting enzyme activity and finding novel powerful and safe inhibitors are highly important in agriculture, food, medical, and pharmaceutical industries. In this regard, in the present study, some novel synthetic pyridine-based compounds including 2,6-bis (tosyloxymethyl) pyridine (compound 3), 2,6-bis (butylthiomethyl) pyridine (compound 4), and 2,6-bis (phenylthiomethyl) pyridine (compound 5) were synthesized for the first time, and their inhibitory potencies were assessed on mushroom tyrosinase diphenolase activity. The results showed that while all tested compounds significantly decreased the enzyme activity, compounds 4 and 5 had the highest inhibitory effects (respectively, 80 and 89% inhibition with the IC50 values of 17.0 and 9.0 μmol L-1), and the inhibition mechanism was mixed-type for both compounds. Ligand-binding studies were carried out by fluorescence quenching and molecular docking methods to investigate the enzyme-compound interactions. Fluorescence quenching results revealed that the compounds can form nonfluorescent complexes with the enzyme and result in quenching of its intrinsic emission by the static process. Molecular docking analyses predicted the binding positions and the amino acid residues involved in the interactions. These compounds appear to be suitable candidates for more studies on tyrosinase inhibition.

Unravelling High Water Vapor-Induced Inhibitory Effects on Pt/Co3O4 Catalysts toward Benzene Oxidation.

Water vapor inevitably exists in the environment, which causes adverse impacts on many crucial chemical reactions. However, high water vapor of up to 10 vol %─relevant to a broad spectrum of industrial practices-for catalytic implications has been less investigated or neglected. As such, we explored an industry-relevant, humidity-highly sensitive benzene oxidation only in the presence of 10 vol % water vapor using the well-established Pt/Co3O4 catalysts, to bring such an important yet ignored topic to the forefront. Results revealed that Pt/Co3O4 catalysts possessing higher contents of Pt nanoparticles exhibited marked tolerance to water vapor interference. Under an incomplete benzene conversion condition, the input of 10 vol % water vapor indeed impaired the catalytic performance of Pt/Co3O4 catalyst significantly, which, in fact, was caused by the unfavorable formation of carboxylate species covering the catalyst's surface engendering irrecoverable activity loss, instead of the well-accepted water competitive adsorption. While such activity loss can be restored by elevating the reaction to a higher temperature. This study helps us to understand the compromised catalytic activity caused by high humidity, urging the systematic evaluation of well-established catalyst systems in high water vapor-contained conditions and pressing the development of water-tolerant catalysts for real-life application consideration.

Rational Design, Synthesis, and Computational Investigation of Dihydropyridine [2,3-d] Pyrimidines as Polyphenol Oxidase Inhibitors with Improved Potency.

Polyphenol oxidase (PPO) is an industrially important enzyme associated with browning reactions. In the present study, a set of ten new dihydropyridine [2,3-d] pyrimidines (TD-Hid-1-10) were synthesized and was found to be proven characteristically by 1H NMR, 13C NMR, IR, elemental analysis, and assessed as possible PPO inhibitors. PPO was purified from banana using three-phase partitioning, achieving an 18.65-fold purification and 136.47% activity recovery. Enzyme kinetics revealed that the compounds TD-Hid-6 and TD-Hid-7 are to be the most potent inhibitors, exhibiting mixed-type inhibition profile with IC50 values of 1.14 µM, 5.29 µM respectively against purified PPO enzyme. Electronic structure calculations at the B3LYP/PBE0 level of theories using def-2 SVP, def2-TZVP basis sets with various molecular descriptors characterized the electronic behavior of studied derivatives TD-Hid-1-10. Molecular electrostatic potential (MEP) and reduced density gradient analyses of RDG-NCI provided insights into charge distributions and weak intermolecular interactions. Docking study simulations predicted binding poses within crucial amino acid sequence in the 2y9x enzyme's active site, which is typically similar in sequence to the PPO form is not allowed. Ligands were analysed in terms of binding energies, inhibitor concentrations (mM) and various molecular interactions such as H-bonds, H-carbon, π-carbon, π-sigma, π-sigma, π-π T-shaped, π-π stacked, π-alkyl, Van der Waals and Cu interactions. The lowest binding energy (-7.83kcal/mol) and the highest inhibitory effect (1.83 mM) were shown by the ligand Td-Hid-6, which forms H-bonds with Met280 and Asn260, exhibits π-sigma interactions with His61 and π-alkyl interactions with Val283. Other ligands also showed different interactions with various amino acids; for example, the Td-Hid-1 ligand formed H-bonds with His244 and showed π-sigma interactions with His244 and Val283.

Inhibition of Botrytis cinerea and Escherichia coli by Lactic Acid Bacteria on Leafy Vegetables

The evaluation of the potentiality of lactic acid bacteria (LAB) strains isolated from fermented products to inhibit Botrytis cinerea and Escherichia coli O157:H7 growth on spinach and lettuce was conducted. From a total of forty LAB strains tested, three were selected due to their high inhibitory effect on plant pathogenic fungi. The identification of these isolates based on a 16S rRNA gene fragment sequence analysis confirmed the genus of Levilactobacillus sp. and Lactiplantibacillus sp. An effective method of coating LAB isolates on the lettuce and spinach surface was developed. The leaves were immersed in bacterial suspension (5.0 × 106 cfu mL−1) for 4 s and drained on tissue paper. LAB survived on lettuce and spinach leaves for 8 days at 6 log10 cfu g−1. Additionally, these bacteria decreased the number of filamentous fungi on the leaves. These isolates were found to inhibit the growth of B. cinerea and E. coli O157:H7 in vitro conditions in growing microbiological media. Their efficacy was confirmed in vivo conditions. These isolates inhibited the development of grey mould caused by B. cinerea on lettuce leaves. Two LAB isolates reduced the abundance of the pathogenic bacterium E. coli on spinach leaves by about 0.7 log10 cfu g−1. In glasshouse conditions, LAB stimulated the growth of examined plants. The lactic acid bacteria used in this study showed the capacity to be used as possible alternatives to chemical compounds in the protection of leafy vegetables against grey mould and for a decrease in E. coli O157:H7 contamination.

Impact of pH and ZnO NPs on the fabricated PVA-PVP/ZnO nanofibers: Morphology, absorption behavior, anticancer, and antibacterial activity

In this study, a cost-effective hydrothermal method was successfully used to synthesize ZnO NPs at different pH levels (8, 10, and 12). Nanofibers were produced from polymeric blends PVA-PVP and PVA-PVP/ZnO nanocomposite precursor through electrospinning. XRD analysis revealed the hexagonal wurtzite structure of the synthesized ZnO NPs, with the dominant crystal plane (101). The impact of pH variation was evident in the increased intensity values of the peaks corresponding to (100), (002), and (101) planes as pH levels rose. The average crystallite size decreased from 31.4 to 27.0 nm using Scherrer's calculation, while the microstrain increased from 11.2 to 12.4 ×10−4 as the pH increased from 8 to 12. As wellas the average particle size of the ZnO NPs decreased from 75.05 to 51.35 nm with increasing pH levels, as depicted in FESEM images. The PVA-PVP/ZnO electrospun nanofibers exhibited smooth surfaces and uniform structures, with average diameters of 80.14, 93.33, and 124.13 nm for pH 8, 10, and 12, respectively. The calculation of the optical energy gap using the ASF approach closely matched Tauc's model, ranging from 3.57 to 3.20 eV. Evaluation of the anticancer activity of the nanofibers against MCF-7 cells showed an increase in cytotoxicity from 18 to 64 % with varying concentrations of ZnO NPs ranging from 6.25 to 100 μg/ml. The highest inhibitory effect (about 16 mm) was observed at pH 12 against gram-positive (Staphylococcus aureus).

Study on Optimization of Liquid Fermentation Medium and Antitumor Activity of the Mycelium on Phyllopora lonicerae.

Phylloporia lonicerae is an annual fungus that specifically parasitizes living Lonicera plants, offering significant potential for developing new resource food and medicine. However, wild resources and mycelium production of this fungus is limited, and its anti-tumor active ingredients and mechanisms remain unclear, hampering the development of this fungus. Thus, we optimized the fermentation medium of P. lonicerae and studied the anti-tumor activity of its mycelium. The results indicated that the optimum fermentation medium consisted of 2% sucrose, 0.2% peptone, 0.1% KH2PO4, 0.05% MgSO4·7H2O, 0.16% Lonicera japonica petals, 0.18% P fungal elicitor, and 0.21% L. japonica stem. The biomass reached 7.82 ± 0.41 g/l after 15 days of cultivation in the optimized medium, a 142% increase compared with the potato dextrose broth medium, with a 64% reduction in cultivation time. The intracellular alcohol extract had a higher inhibitory effect on A549 and Eca-109 cells than the intracellular water extract, with half-maximal inhibitory concentration values of 2.42 and 2.92 mg/ml, respectively. Graded extraction of the alcohol extract yielded petroleum ether phase, chloroform phase, ethyl acetate phase, and n-butanol phase. Among them, the petroleum ether phase exhibited a better effect than the positive control, with a half-maximal inhibitory concentration of 113.3 μg/ml. Flow cytometry analysis indicated that petroleum ether components could induce apoptosis of Eca-109 cells, suggesting that this extracted component can be utilized as an anticancer agent in functional foods. This study offers valuable technical support and a theoretical foundation for promoting the comprehensive development and efficient utilization of P. lonicerae.

Human estrogen receptor alpha (ERα) targeted cyclic peptides inhibit cell growth and induce apoptosis in MCF-7 cells

Abstract Objectives Human estrogen receptor alpha (ERα) is considered an important target, especially in the treatment of breast cancer, as it has a vital role in cancer development. ERα-targeted therapies generally target the ligand binding domain (LBD) of ERα. However, over time, cells develop resistance to this mechanism alternative approaches to inhibit ERα activity target ERα–DNA or ERα–cofactor interactions. Inhibitors of ERα–cofactor interactions are designed by targeting the hydrophobic hollow region of the receptor box LXXLL motif. Methods In this context, helix-stabilized cyclic peptides (SPs) designed with in silico approaches were obtained by solid phase peptide synthesis. The effects of SPs on MCF-7 cells were examined with MTT and ATP, and qPCR and flow cytometry were used for further analysis. Results Our results demonstrated that the SPs were effective only in MCF-7 cells expressing ERα. In addition, cyclic peptide combinations (SPCs) showed anti-proliferative and toxic effects on MCF-7 cells. The impact of SPCs with the highest inhibitory effect in MCF-7 cells on ERα-related genes and markers of apoptosis was revealed. Moreover, the flow cytometry analysis result used to examine apoptotic cells proved the apoptosis of SPCs in MCF-7 cells. Conclusions These findings suggest that our novel SPs, which inhibit coactivator interactions of ERα, induce apoptosis of MCF-7 cells. Thus, considering this strong effect of SPs in the inhibition of receptors, it is pointed out that they can be further developed as an alternative to current clinical treatments or as an auxiliary approach in the generating of new targeted peptide-based therapies.