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Essential oils (EOs) from plants have attracted the attention of scientists due to their multiple biological activities. Antimicrobial activity of essential oils is the main reason for their widespread use in industries, which is determined through minimum inhibitory concentration (MIC) by using in vitro models. Therefore, the MIC is a crucial parameter to evaluate the antimicrobial potential of EOs. 492 papers were screened through the critical review of the related literatures in the past 50 years using four databases and read deeply for an outline. This review first listed common MIC determination methods of EOs, including agar diffusion method, agar dilution method, broth dilution method, E-Test, thin-layer chromatography-bioautography, etc. and their merits and demerits were introduced in detail. Agar and broth dilution methods are the gold standards in a more exact approach for MIC determination. Then, their functions and factors influencing the accuracy were listed and analyzed deeply. The application of the MIC determination in food and pharmaceuticals was finally discussed. This study is believed to help researchers to choose the right method and conditions for research and development of the tested EOs. [ABSTRACT FROM AUTHOR]

AbstractCopper oxide nanoparticles (CuO NPs) are promising biologically active materials due to their broad-spectrum antimicrobial, antifungal, and antiviral properties. In this study, CuO NPs were synthesized using a green synthesis method employing Juglans regia L. (walnut) leaf extract under ambient conditions. A Box-Behnken design (BBD) was applied within the framework of response surface methodology to optimize the synthesis process, focusing on three critical parameters: copper salt concentration, extract volume, and calcination temperature. The structural and morphological characteristics of the synthesized CuO NPs were systematically investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM-EDS), Fourier transform infrared spectrometry (FT-IR), ultraviolet–visible (UV–Vis) spectroscopy, and thermogravimetric analysis (TGA). The antimicrobial efficacy of the CuO NPs was also assessed by determining the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) against a range of bacterial strains, yeasts, and filamentous fungi. The findings demonstrated the successful formation of highly dispersed crystalline CuO NPs, with average crystallite sizes ranging from 13.39 to 25.26 nm. SEM analysis confirmed the presence of spherical, homogeneous NPs with an average diameter of 14 µm. The optimized synthesis conditions (0.125 M copper salt, 5% Juglans regia L. extract, and a calcination temperature of 300 °C) yielded CuO NPs with a mean crystallite size of 24.51 nm and an MFC of 113.051 µg/mL. Notably, the synthesized CuO NPs exhibited broad-spectrum antimicrobial activity, with some samples demonstrating superior antifungal efficacy compared to the control antifungal antibiotic at a concentration of 125 µg/mL. [ABSTRACT FROM AUTHOR]

The leaves of Citrus deliciosa Tenore were collected in southern Brazil, dried, and subjected to the hydrodistillation process to obtain the essential oil. The extraction of essential oil yielded 0.97% ± 0.04. The chromatographic profile of this compound revealed 11 substances, being methyl N-methyl-anthranilate (75.1%), γ-terpinene (13.8%), and Limonene (7%) as major substances. The essential oil shows antifungal action against all tested yeasts, with promising action against Cryptococcus neoformans, Cryptococcus gattii, and Trichosporon asahii. This compound was also able to inhibit the biofilm production of Candida albicans, Candida glabrata, Candida parapsilosis, and T. asahii. The essential oil of tangerine showed weak antioxidant action. It did not show cytotoxicity in human mononuclear cells. It is hoped that these results may guide future studies for the production of formulations that can be used in the treatment of biofilms caused by yeasts, as well as in candidiasis, cryptococcosis, and/or trichosporonosis. [ABSTRACT FROM AUTHOR]

A series of new 4-hydroxy-2-thioxo-4-trifluoromethyl-hexahydro-pyrimidin-5-yl]-p-tolyl-methanone derivatives were synthesized through one-pot three-component method using 4,4,4-trifluoro-1-p-tolyl-butane-1,3-dione, thiourea, and various substituted benzaldehydes. The structures of newly synthesized products were elucidated by spectroscopic studies such as IR, NMR (proton and carbon), mass spectra, and elemental analyses. The final products were screened for their antioxidant activity, anti-inflammatory activity against LPS-induced cell death in RAW 264.7 macrophage cell lines, antibacterial and antifungal activity using in vitro methods. The results revealed that the compounds such as 10e and 10i against DPPH and H2O2; 10a, 10e, 10h, and 10i against LPS induced inflammation in RAW 264.7 cell lines; 10a, 10b, 10c, 10d, and 10e against all the microbial strains tested have exhibited higher content of activity in vitro than the rest of the title compounds when compared to the standard drugs. In overall, 10a, and 10e have shown the most promising activity against all the systems tested. Hence, among all the title compounds, at least a few will stand as next generation antioxidant, anti-inflammatory and antimicrobial agents in future. [ABSTRACT FROM AUTHOR]

A new cladosporol derivative xylophilum A (1), together with 10 known compounds (2–11), were isolated from the rice fermentation of the fungus Cladosporium xylophilum. Their structures were established by extensive spectroscopic methods and comparison of their NMR data with literatures. The antimicrobial activity of compound 1 against 11 kinds of pathogenic microbial was evaluated, but no significant activity was found (MIC >100 μg/ml). [ABSTRACT FROM AUTHOR]

The aim of the study was to characterise the chemical composition of the essential oil extracted from a Chinese traditional aromatic herb, Artemisia sieversiana Ehrhart ex Willd and investigate its antimicrobial activities against Staphylococcus aureus, the test bacterium, using thin-layer chromatography-direct bioautography (TLC-DB). Gas chromatography-mass spectrometry analysis showed that the essential oil was dominated by chamazulene (44.44%). Undeveloped TLC-DB enabled the measurement of zone of inhibition as valid as and more sensitive than the traditional agar diffusion method. The overall antimicrobial effect was weak at the tested concentration range and the antimicrobial strength did not exhibit concentration dependence. At high essential oil concentration (>1000μg/ml), size of zone of inhibition was all <7mm. Developed TLC-DB separated the components and visualised the inhibition of bacterial growth on the plate surface where the active antimicrobials were determined to be the minor components, hydroxylated terpenes, rather than the dominant component, chamazulene. [ABSTRACT FROM AUTHOR]

AbstractThis study focuses on the synthesis, characterization, and potential applications of an amphiphilic nanocomposite composed of Poly(ε-caprolactone)-Poly(ethylene glycol)-Poly(ε-caprolactone) (PCL-PEG-PCL) and modified Maghnite (Algerian montmorillonite clay), referred to as PCL-PEG-PCL/Maghnite. The nanocomposite was synthesized via in-situ copolymerization of ε-caprolactone and polyethylene glycol, in the presence of intercalated Maghnite modified with tetrabutylammonium hydrogen sulfate (TBHSA). A variety of characterization techniques, including Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) were employed to analyze the structural properties of the resulting nanocomposite. Additionally, the antimicrobial activity assessment of the nanocomposites demonstrated their effectiveness against all the bacterial strains tested. Besides, the nanocomposite 10% demonstrated promising results as a gel for wound healing, confirming its effectiveness in promoting tissue regeneration and wound closure. [ABSTRACT FROM AUTHOR]

AbstractIn this context, we designed and synthesized a series of hydrazonal and their related indeno[1,2-b]pyridin-5-one derivatives to investigate their antibacterial and anti-biofilm properties. Several of the synthesized compounds exhibited significant efficacy against all microorganism species tested. Most of the compounds demonstrated favorable results when tested against Gram-positive bacteria. The derivatives 4a, 4f, 6c, and 6f exhibit the highest antimicrobial efficacy, as indicated by their minimum inhibitory concentration (MIC) values ranging from 4 to 512 μg/mL. We conducted additional investigations on 4a, 6c, and 6f for the purpose of examining their synergy using Checkerboard assay. Compound 6c demonstrated a synergistic impact against methicillin-sensitive Staphylococcus aureus (MSSA) and Pseudomonas aeruginosa, while exhibiting moderate synergistic activity against methicillin-resistant Staphylococcus aureus (MRSA). In addition, the simultaneous use of gentamycin with compounds 4a and 6f demonstrates a synergistic impact in fighting against methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. Three chosen compounds were evaluated for their antibiofilm efficacy. Application of 4a, 6c, and 6f effectively reduced the production of biofilms in MRSA, MSSA, and Pseudomonas aeruginosa, resulting in a significant decrease compared to the untreated samples. In addition, ADME and pharmacokinetic analyses were conducted for the three most potent derivatives, namely 4a, 6c, and 6f. Compounds 4a and 6c were subjected to docking in the LasR Quorum-Sensing Receptor, whereas compounds 6c and 6f were docked in the sortase enzyme. [ABSTRACT FROM AUTHOR]

The growth of bacteria and fungi may cause disease inf human or spoilage of food. New antimicrobial substances need to be discovered. Lactoferricin (LFcin) is a group of antimicrobial peptides derived from the N-terminal region of the milk protein lactoferrin (LF). LFcin has antimicrobial ability against a variety of microorganisms, which is significantly better than that of its parent version. Here, we review the sequences, structures, and antimicrobial activities of this family and elucidated the motifs of structural and functional significance, as well as its application in food. Using sequence and structural similarity searches, we identified 43 new LFcins from the mammalian LFs deposited in the protein databases, which are grouped into six families according to their origins (Primates, Rodentia, Artiodactyla, Perissodactyla, Pholidota, and Carnivora). This work expands the LFcin family and will facilitate further characterization of novel peptides with antimicrobial potential. Considering the antimicrobial effect of LFcin on foodborne pathogens, we describe the application of these peptides from the prospective of food preservation. [ABSTRACT FROM AUTHOR]

Dental caries is a highly prevalent oral disease affecting billions of individuals globally. The disease occurs chemically as a result of breakdown of the tooth surface attributed to metabolic activity in colonizing biofilm. Biofilms, composed of exopolysaccharides and proteins, protect bacteria like Streptococcus mutans, which is notable for its role in tooth decay due to its acid-producing abilities. While various antimicrobial agents may prevent biofilm formation, these drugs often produce side effects including enamel erosion and taste disturbances. This study aimed to examine utilization of the Mentha piperita essential oil as a potential antibiofilm activity agent against S. mutans. M. piperita oil significantly (1) reduced bacterial biofilm, (2) exhibited a synergistic effect when combined with chlorhexidine, and (3) did not induce cell toxicity. Chemical analysis identified the essential oil with 99.99% certainty, revealing menthol and menthone as the primary components, constituting approximately 42% and 26%, respectively. Further, M. piperita oil eradicated preformed biofilms and inhibited biofilm formation at sub-inhibitory concentrations. M. piperita oil also interfered with bacterial quorum sensing communication and did not produce any apparent cell toxicity in immortalized human keratinocytes (HaCaT). M. piperita represented an alternative substance for combating S. mutans and biofilm formation and a potential combination option with chlorhexidine to minimize side effects. An in-situ performance assessment requires further studies. [ABSTRACT FROM AUTHOR]

AbstractLectins, diverse proteins adept at detecting and binding carbohydrates without altering them, are pivotal in plant life. They facilitate cell communication, development, and defense mechanisms. This article explores lectins’ varied biological roles, focusing on their versatility and significance. Plant lectins exhibit diverse biochemical traits, impacting immune regulation and possessing antibacterial properties vital in plant defense. Additionally, they showcase disease-fighting potential. Their multifaceted nature, spanning biochemical properties, and functional roles underscores their importance in intricate biological processes. This concise review highlights wide-ranging applications of plant lectins, emphasizing their crucial role in immunomodulation, antibacterial functions, and contributions to plant health and defense mechanisms. [ABSTRACT FROM AUTHOR]

In this study, the chemical composition, antioxidant and antimicrobial activities of the essential oil from leaves and flowers of collected Gentianella longibarbata (Gilg) Fabris from the highlands of Ecuador were studied. The most abundant components were aliphatic compounds, predominantly methyl ketones (35.7%), and aromatic compounds (37.6%). The major compounds included carvacryl acetate (18.5%), nonan-2-one (14.5%), undecane-2-one (13.5%), and carvacrol (11.4%). Antioxidant activity was examined using DPPH, ABTS, and FRAP assays. The antioxidant activity of the essential oil, evaluated by DPPH (IC50 14.01 mg/mL) and ABTS (IC50 38.87 mg/mL) assays, exhibited a strong ability in scavenging radicals. The essential oil also showed ferric reducing activity. Antimicrobial activity of the essential oil was evaluated against four bacteria and a yeast. The essential oil showed very good activity against S. aureus, E. coli and P. aeruginosa, but low activity against S. enterica serovar and C. albicans. The MIC value of the essential oil varied from 0.43 μL/mL to 23.72 μL/mL. [ABSTRACT FROM AUTHOR]

The methanolic extract of Indigofera dosua leaves was subjected to GC-MS analysis, its antioxidant and antimicrobial potential. Sixteen compounds were identified having resorcinol TMS derivatives, propanoic acid, dimethyl(ethenyl)silyl ester, 4-O-methylmannose, hexadecanoic acid, trimethylsilyl ester, 9,12,15-octadecatriene-1-ol, and phytol as major components. FRAP content was 40.24 ± 0.54AAE/g, and the IC50 values were 8.25 ± 0.04 µg mL−1 and 19.05 ± 0.15 µg mL−1 when employing DPPH and ABTS, respectively. Total phenolics (50.2 ± 0.48 mg GAE/g) and total flavonoid content (5.33 ± 0.40 mg QE/g) were estimated. Antibacterial activity was observed, showing significant inhibition against Pseudomonas aeruginosa and Proteus mirabilis with MIC values 12.5 and 25 mg mL−1, respectively. [ABSTRACT FROM AUTHOR]

Recently, research on functional packaging films and their application to food preservation has been actively conducted. This review discusses recent advances and opportunities for using quercetin in developing bio-based packaging films for active food packaging. Quercetin is a plant-based yellow pigment flavonoid with many useful biological properties. Quercetin is also a GRAS food additive approved by the US FDA. Adding quercetin to the packaging system improves the physical performance as well as the functional properties of the film. Therefore, this review focused on quercetin's effect on the various packaging film properties, such as mechanical, barrier, thermal, optical, antioxidant, antimicrobial, and so on. The properties of films containing quercetin depend on the type of polymer and the interaction between the polymer and quercetin. Films functionalized with quercetin are useful in extending shelf life and maintaining the quality of fresh foods. Quercetin-added packaging systems can be very promising for sustainable active packaging applications. [ABSTRACT FROM AUTHOR]

AbstractThis paper describes the synthesis and in vitro biological evaluation of new compounds designated as 5(a-h) and 8(a-f). These compounds were synthesized by the reaction of thiazole derivative (3) or thiadiazole derivative (7) with urea and various aromatic aldehydes 4(a-h) in ethanol. The structures of the synthesized compounds were checked by IR,1H,13C NMR, and Mass spectroscopy. The antibacterial and antifungal activities of the compounds were evaluated against Escherichia coli (Gram-negative), Staphylococcus aureus (Gram-positive), and Candida albicans (fungus) using agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal/fungicidal concentration methods. The cytotoxic activities of these compounds against HT-29 and A-549 cancer cell lines were assessed in vitro by the MTT method. Our studies showed compounds 8c and 8f to have the most expressed antibacterial activity against S. aureus, while compounds 8c and 8d were the most potent against E. coli. Compounds 5h and 8e showed the highest antifungal activity against C. albicans, and compound 5f showed the most potent activity against the tested cancer cell lines. [ABSTRACT FROM AUTHOR]

A new alkaloid named aspergilalkaloid A (1) with pyridoindole hydroxymethyl piperazine dione structure along with six known compounds 2-7 were isolated from deep-sea derived fungus Aspergillus sp. HDN20-1401. The structure including absolute configuration was elucidated by extensive NMR analyses, HRESIMS, ECD calculation, and theoretical NMR calculation with DP4+ analysis. All isolated compounds were tested for antimicrobial and anticancer activity. Aspergilalkaloid A (1) showed inhibitive activity against Bacillus cereus with MIC value of 12.5 μM and weak activity against MRCNS. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the phytotoxic, genotoxic, cytotoxic and antimicrobial effects of the Mentha arvensis L. essential oil (EO). The biological activity of M. arvensis EO depended on the analyzed variable and the tested oil concentration. Higher concentrations of EO (20 and 30 µg mL−1) showed a moderate inhibitory effect on the germination and growth of seedlings of tested weed species (Bellis perennis, Cyanus segetum, Daucus carota, Leucanthemum vulgare, Matricaria chamomilla, Nepeta cataria, Taraxacum officinale, Trifolium repens and Verbena × hybrida). The results obtained also indicate that the EO of M. arvensis has some genotoxic, cytotoxic and proliferative potential in both plant and human in vitro systems. Similar results were obtained for antimicrobial activity against eight bacteria, including multidrug-resistant (MDR) strains [Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Escherichia coli, extended-spectrum beta-lactamase-producing (ESBL) E. coli, Pseudomonas aeruginosa and Salmonella enterica subsp. enterica serovar Enteritidis], with the effect on multidrug-resistant bacterial strains. Research indicates that the EO of M. arvensis shows phytotoxic, genotoxic, cytotoxic and antimicrobial effects, as well as its potential application as a herbicide and against various human diseases. [ABSTRACT FROM AUTHOR]

Three new α-pyrone derivatives, annularins L–N (1–3), were isolated from the EtOAc extract of Penicillium herquei MA-370, a fungus obtained from the rhizospheric soil of the mangrove plant Rhizophora mucronata. The planar structures of compounds 1–3 were determined based on comprehensive spectral interpretation of the NMR and MS data. The absolute configuration of 1 was determined by X-ray crystallographic data and that of 2 was assigned by TDDFT calculations of its ECD spectrum and cotton effects comparison with those of 1. The antimicrobial activity of compounds 1–3 was evaluated. [ABSTRACT FROM AUTHOR]

A pair of epimers of flavonoid alkaloids, with a pyrrolidone moiety, 2S,5′′R-eupodoratin A (1), 2S,5′′S-eupodoratin A (2), together with two known analogues, drahebephin A (3), drahebephin B (4), were isolated from the flowers of Chromolaena odorata (L.) R.M.King & H.Rob. Their structures were elucidated on the basis of HR-ESI-MS, 1D/2D NMR spectral analyses. The absolute configuration of compounds (1) and (2) was determined by its experimental and calculated electronic circular dichroism (ECD) spectra. All compounds were isolated from the Asteraceae family for the first time. The ABTS·+ scavenging activity of compound (4) reached 93.56% at a concentration of 0.5 mM, while the scavenging capacity of positive control Trolox was 55.94%. In addition, all compounds show moderate antimicrobial activity against Escherichia coli (ATCC, 337304), Staphylococcus aureus (ATCC, 337371) and Candida albicans (ATCC, 186382) with a MIC value of more than 50 µg/mL. [ABSTRACT FROM AUTHOR]

In this study, a mixed sol-gel technique using silicate, polyvinyl alcohol (PVA), and polyethyleneimine (PEI) was used to various polymers based on PEI and silica gel. The c-PEI blend co-polymer was synthesized by cross-linking branching PEI in an aqueous solution with PVA. The produced c-PEI particles were highly positively charged and fit inside the range of tens to hundreds of nanometers of silica gel. It has been shown that the prepared c-PEI nanocomposite is a very effective antimicrobial, anti-inflammatory, and antioxidant material. In addition to the appropriate investigation of the anti-inflammatory activity using human red blood cells (HRBCs) stabilization, the developed materials were used to explore antimicrobial activity against yeast (Candida albicans ATCC-10231), Gram-negative bacterial strain (Escherichia coli ATCC-25922), and Aspergillus niger NRRL-3 as a fungus. FTIR, XRD, TEM, TGA, and DSC were among the biological and chemical methods used to characterize the produced c-PEI nanocomposites. The agar diffusion method was used to assess the biological activity of the synthesized compounds, and the results revealed a range in their in vitro-antimicrobial inhibitory activity. Based on the type of pathogenic microbe, the majority of the test substances showed a wide range of activity. The examined substances may be appropriate for the creation of an innovative antibacterial and antifungal medicinal medication. [ABSTRACT FROM AUTHOR]

Rubus moluccanus L., commonly known as Molucca bramble or broad-leaf bramble is a member of family Rosaceae which occurs mainly in tropical Asia and Australia. It has applications in indigenous medicines and is used in the treatment of number of ailments like headache, diarrhoea, dysentery, abdominal pain, nocturnal micturition of children and enhancement of female fertility. This plant is a rich and valuable source of bioactive flavonoids, terpenes and other chemical compounds. The presence of these active chemical compounds exerts antibacterial, antifungal, antihelminthic and antioxidant activities. Regardless of its use in various diseases and disorders, the information about this plant is scanty. So the present review assessed and summarised the knowledge on taxonomy, morphology, geographical distribution, nutritional value, ethnobotany, phytochemistry and biological activities of R. moluccanus. [ABSTRACT FROM AUTHOR]

This study represents the first investigation of the chemical composition and the antioxidant and antimicrobial activities of Ononis aurasiaca Förther & Podlech, a plant species endemic to the Aures Mountains of Algeria. The essential oil of the plant aerial parts was analysed using GC-MS. The in vitro antioxidant activity was evaluated using three methods. A total of 44 compounds were identified. The major constituents were dodecanal, hexahydrofarnesylacetone, 2-tridecanone, phytol, 1-heneicosene, and n-heneicosane. The oil displayed significant activity in the β-carotene bleaching assay, moderate scavenging activity against DPPH radicals and a low ability to reduce iron ions. Antibacterial tests conducted on four strains revealed effectiveness primarily against Gram-positive strains, specifically Staphylococcus aureus ATCC 25923 and ATCC 43300, while showing limited impact on Gram-negative strains, Pseudomonas aeruginosa ATCC 27853 and Escherichia coli ATCC 25922. Antifungal activity tests involving two moulds revealed a stronger inhibition against Scedosporium apiospermum compared to Aspergillus niger. [ABSTRACT FROM AUTHOR]

A novel set chalcones 3a-d was efficiently synthesized in elevated produces across the condensing process of Claisen-Schmidt. An eco-friendly and efficient process was designed for creating a novel desired products 5a-f and 7a-f, respectively with excellent yields. This synthesis was accomplished by reacting acetophenone derivatives 1a-d, heteroaromatic aldehydes 2a,b and aminobenzoimidazole 4 or 3-aminopyrazole 6a,b, using acetic acid as both the catalyst and solvent. Solvent optimization was performed during the synthesis of the desired compounds 5a or 7a, highlighting the benefits of using acetic acid that is harmless for the environment, which offers easy procedure, rapid reaction, elevated efficiency and broad tolerance of starting materials. The preferred products were verified through compatible spectroscopic data. The antimicrobial efficacious for all compounds was successfully evaluated against various microorganisms, revealing that 3b exhibited significant antimicrobial activity across all tested microbes, with measurements of the minimum inhibitory concentrations being between 4.80 to 63.8 μM. [ABSTRACT FROM AUTHOR]

Geosmithia pallida (KU693285) was isolated from Brucea mollis an endangered medicinal plant of North-East India. The secondary metabolites, produced by the endophytic fungi, extracted by ethyl acetate were screened for antimicrobial activity. G. pallida extract displayed the highest antimicrobial activity against Candida albicans with a minimum inhibitory concentration of 80.5 ± 1.25 µg/mL. G. pallida also showed the highest antioxidant activity which differed insignificantly from Penicillium sp. (P > 0.05). The G. pallida extract also exhibited the highest cellulase activity and also amylase and protease activities. The cytotoxicity assay of the ethyl acetate extract of this endophyte showed negligible effect (1.93 ± 0.42%) on chromosomal aberration as compared to the control (cyclophosphamide monohydrate) (7.20 ± 1.51%). The internal transcribed spacer rDNA sequence of G. pallida was submitted to the NCBI (Accession number KU693285) from India for the first time. The FT-IR spectrophotometry of the bioactive metabolite of G. pallida showed the presence of different functional groups such as alcohol, carboxylic acids, amines, aromatics, alkyl halides, aliphatic amines and alkynes. The GC-MS analysis revealed the presence of acetic acid, 2-phenylethyl ester; tetracosane; cyclooctasiloxane hexadecamethyl; cyclononasiloxane octadecamethyl; octadecanoic acid; phthalic acid, di(2-propylpentyl) ester and nonadecane, 2,6,10,14,18-pentamethyl as the major compounds in the metabolite. The findings of the present work indicated G. pallida as a potential source of important biomolecules without mammalian cytotoxic effects, which can be utilized for pharmaceutical purposes. [ABSTRACT FROM AUTHOR]

In this work the mucilage obtained from the cladodes of a not previously investigated accession of Opuntia stricta (Haw.) Haw. (syn. Opuntia dillenii (Ker-Gawl) Haw), collected in Sicily, was analysed by 13C-NMR. The yield of mucilage extracted from cladodes in aqueous medium was 2.55%. The monosaccharides identified, after acidic hydrolyses of the mucilage, were arabinose (36.48%), galactose (32.31%), xylose (15.33%), glucose (10.45%) and rhamnose (5.40%). The mucilage showed a sufficient antimicrobial activity and excellent antioxidant property. [ABSTRACT FROM AUTHOR]

\nHIGHLIGHTSThe chemical contents of the endemic Onosma malatyana roots collected from Malatya/Türkiye were determined using the hydrodistillation and the soxhlet methods and antimicrobial activity analysis of the extracts was also performed. The hydrodistillation method applied to the roots of O.malatyana resulted in identifying 31 compounds according to their retention times in GC-MS analysis. Additionally, crude ethyl acetate and crude oil etheric extracts of O.malatyana roots contained 14 compounds each. This research identified that the main component of the essential oil obtained by the hydrodistillation method was palmitic acid comprising 56.48% of the total composition. Additionally, in the crude petroleum etheric extract, oleic acid methyl ester (31.22%); and palmitic acid (24.69%) were identified as the main components in the crude ethyl acetate extract. The results of the antimicrobial activities indicated that O.malatyana root extracts were particularly effective against Gram-positive bacteria, specifically S. aureus and B. subtilis.The study, conducted for the first time, sheds detailed light on the chemical composition and antimicrobial activity of Onosma malatyana roots, highlighting the potential pharmacological importance of the plant.The research, carried out using hydrodistillation and Soxhlet extraction methods, emphasizes the chemical diversity of the plant by identifying various organic compounds, particularly prominent ones such as palmitic acid.Antimicrobial tests show strong inhibitory effects, especially against Gram-positive bacteria like S.aureus and B.subtilis. This indicates the potential of crude petroleum etheric extract as a natural antimicrobial agent.The findings allow for a better understanding of the chemical diversity and pharmacological potential of O. malatyana, enabling future research to target the plant’s phytochemical profile, antimicrobial compound mechanisms, and optimization of cultivation practices. [ABSTRACT FROM AUTHOR]

The newly synthesized 1,2,3-triazole-thiazole hybrids were first evaluated for their antimicrobial activity against different microbial strains. Most of it showed a marked selectivity against Gram-positive and Gram-negative bacterial strains. The MIC assay was then assessed; for S. aureus, 4a was equipotent to the reference neomycin, while 3a, 3b, and 8b were 2-fold lower. For E. coli, compounds 3a, 4a, and 8c were equipotent to neomycin, while 5a was 8-fold higher, and 8d was 2-fold higher. Most of tested compounds showed superiority to the reference drug against C. albicans; 8a and 8e showed MIC value of 16-fold higher than neomycin, while 3a was 8-fold higher. Also, 3b and 8f were 4-fold higher; 8d was 2-fold higher, while 5a was equipotent to neomycin against the same microbe. Further biofilm formation inhibition assay was conducted to the most active compounds, 5a was the most active against the three types of bacterial strains. [ABSTRACT FROM AUTHOR]

The chemical composition, antioxidant and antimicrobial activities of the essential oil from the aerial parts of Rumex obtusifolius L. were studied. To the best of the authors' knowledge, this essential oil has never been fully characterized. The component analysis of the essential oil was done by gas chromatography with flame ionization detector (GC-FID) and mass selective detector (GC-MS). A total of 104 compounds, representing 97.8% of the essential oil, were identified. Aliphatic compounds, mainly methyl ketones (74.2%) and monoterpene hydrocarbons (13.7%) were found to be the most abundant compounds. The major compounds were undecan-2-one (47.6%) and nonan-2-one (13.4%). The antioxidant activity of the essential oil, evaluated by DPPH (IC50 9.11 mg/mL) and ABTS (IC50 36.72 mg/mL) assays, exhibited a weak ability in scavenging radicals. The essential oil also showed a low ferric reducing activity. The essential oil exhibited very good activity against E. coli and S. aureus, but low activities against S. enterica serovar, P. aeruginosa and C. albicans. MIC values of the essential oil varied from 0.38-27.04 μL/mL, with the lowest for E. coli. [ABSTRACT FROM AUTHOR]

The synthesis of CeO2 nanoparticles (CeO2 NPs) using Papaya (Carica papaya) leaves extract was demonstrated in this study. The main components of Carica papaya leaves extracts were investigated through different phytochemical tests. These tests have been indicated the presence of alkaloids, flavonoids, phytosterols, terpenoids, glycosides, and saponins in the extract. These secondary metabolites assist in the capping, stabilization, and reduction of metal oxide-based nanoparticles. Different analytical techniques were used to characterize CeO2 NPs. Fourier transform infrared (FTIR) spectroscopy revealed the presence of O-H, C = O, C-O, Ce-O, Ce-C, etc. on the surface of green synthesized CeO2 NPs. The antibacterial and antifungal activities of biologically synthesized CeO2 NPs were investigated using well diffusion method. For Streptococcus mutans, Pseudomonas aeruginosa, Bacillus subtilis, Escherichia coli, Aspergillus fumigatus, and Aspergillus niger, the zones of inhibition around the CeO2 NPs were 34, 28, 38, 44, 36, and 34 mm, respectively. [ABSTRACT FROM AUTHOR]

The present study examined the antimicrobial effects of betel leaf (Piper betle) extracts against Vibrio spp. along with the isolation of the most prevalent bioactive components using a bioassay-guided purification. Following a preliminary screening, the ethanolic extract proved the most effective and performed to silica gel chromatography, followed by reversed phase HPLC to isolate the active components. By means of subsequent UHPLC-orbitrap-ion trap mass spectrometry, two compounds were identified as (E)-3-phenylprop-2-enoic acid (cinnamic acid) and [4-(1-hydroxyprop-2-enyl)phenyl] acetate (1'−hydroxychavicol acetate). The compounds showed anti-microbial activity against Vibrio species including V. parahaemolyticus, V. harveyi, V. alginolyticus, V. vulnificus and V. anguillarum. Their antibacterial action was quantified by a microdilution assay showing that cinnamic acid displays more potent activity (IC50, 21–121 µg/mL) compared to 1'-hydroxychavicol acetate (IC50, 24–365 µg/mL). These findings propose the potential use of the betel leaf as a substitute for antibiotics to combat Vibrio infections in shrimp aquaculture. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the chemical composition and antimicrobial activity of Jasminum grandiflorum L. essential oil produced for the first time at industrial level by steam distillation. Volatile and chiral compositions were analyzed by GC-MS and GC-FID. In total 130 volatile compounds were identified, which constituted more than 98% of the oils. The results revealed significant differences in terms of volatile compounds between jasmine essential oil and the absolute. Sensorial evaluation revealed the essential oil had a youthful and dynamic character with a bright, floral scent, while the absolute had a more mature and sensual scent that was richer. Antimicrobial activity of both products against eighteen human pathogens and cosmetic contaminants was evaluated. The results showed that essential oil exhibited greater antimicrobial activity, inhibiting 8 out of 17 microbial strains within the MIC range ≤800 µg/mL, compared to 2 out of 17 in the case of the absolute. [ABSTRACT FROM AUTHOR]

Poly (1,4-phenylene ether ether sulfone) (PEES) is a commonly used polymer in membrane technology for water treatment applications such as water purification and blood dialyzing in hemodialysis. In this study, PEES was chemically modified by nitration, yielding nitrated Poly (1,4-phenylene ether ether sulfone) (NPEES). Following that, NPEES nanocomposites (NCs) comprise multi-walled carbon nanotubes (MWCNTs), and the process involved the synthesis of reduced graphene oxide-oxidized single-walled carbon nanotubes, abbreviated as reduced (GO-oxSWCNTs). Various characterization techniques were used on the created membranes, such as Fourier-transform infrared spectroscopy (AT-FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis. All polymer nanocomposites were found to be amorphous, according to the XRD patterns. SEM scans revealed random crater-like features on the surface of NPEES, but MWCNTs and reduced (GO-oxSWCNTs) NCs were distributed evenly on the polymer surface. The primary goal of this study was to evaluate the antimicrobial activity of modified NPEES membranes against two Gram-positive bacteria, Staphylococcus aureus (S. aureus) and Bacillus subtilis (B. subtilis), two Gram-negative bacteria, Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli), and a fungus, Candida albicans (C. albicans). All modified membranes, including NPEES, NPEES/MWCNTs NCs, and NPEES/MWCNTs/reduced (GO-oxSWCNTs) NCs, exhibited antibacterial activity against S. aureus and B. subtilis. Notably, when compared to NPEES/MWCNTs NCs and NPEES/MWCNTs/reduced (GO-oxSWCNTs) NCs, the NPEES membrane had higher antibacterial activity, generating a 12 mm inhibitory zone. Furthermore, molecular docking studies revealed a strong fit of the tested polymer nanocomposites into the DNA gyrase B active site (PDB ID: 4uro), which was consistent with the practical results of their antibacterial activity evaluation. [ABSTRACT FROM AUTHOR]

The present work involves an eco-friendly, green, and cost-efficient synthesis of reduced graphene oxide using green extracts of curry leaves and Tulsi seeds as reducing agents. The synthesized reduced GOs (CL-rGO and TS-rGO) were confirmed by XRD, FESEM, EDS, FT-IR, UV-VIS, and TGA studies. The disappearance of the peak at 9.90° and the appearance of a new peak at 2θ = 24.56° and 2θ = 25.62° and a decrease in interlayer spacing from 0.88 nm to 0.34 nm and 0.36 nm in CL-rGO and TS-rGO respectively confirmed the synthesis of reduced GO. The C/O atomic ratio of CL-rGO and TS-rGO was found 4.35 and 4.19 as compared to synthesized GO (C/O atomic ratio 2.65) which confirmed the synthesis of reduced GO. Further, the catalytic applications of synthesized CL-rGO and TS-rGO were studied for the reduction of cinnamaldehyde to cinnamyl alcohol in an aqueous medium yielding 90-91%. Moreover, the degradation of methylene blue and malachite green dyes was studied and found that both dyes were eliminated within 25 and 30 min in dark conditions using CL-rGO and TS-rGO respectively. Both CL-rGO and TS-rGO showed significant antimicrobial activity against different fungal strains but specifically CL-rGO against M. furfur with the minimum inhibitory concentration of 125 µg/mL. Furthermore, CL-rGO and TS-rGO exhibited excellent antimicrobial activity against E. coli with minimum inhibitory concentrations of 62.5 µg/mL and 31.25 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

The soil-derived fungus Talaromyces thailandensis PSU-SPSF059 produced one new vermistatin derivative, talarostatin, and seven known compounds including two vermistatins, two chrodrimanins, two diphenyl ethers and one penicillide derivative. Extensive spectroscopic analysis was performed to identify their structures. The absolute configuration of talarostatin was determined by comparing the experimental and calculated electronic circular dichroism data. The antimicrobial and cytotoxic activities of the isolated secondary metabolites were also evaluated. [ABSTRACT FROM AUTHOR]

A series of chloroacetamide derivatives (1-22) was synthesized to address the urgent need for new antimicrobial and antioxidant agents. The chemical structures were confirmed by 1H-NMR, 13C-NMR and MS spectroscopic analyses. Most compounds inhibited in vitro Gram-positive bacteria S. aureus and B. cereus as well as Gram-negative bacteria (E. coli and P. aeruginosa) and yeast (C. albicans). Interestingly, compound 13 showed the broadest spectrum, especially against B. cereus (MIC = 10 mg/L). Compounds 6 and 20 displayed potent activity against C. albicans (EC50 = 197.02 and 189.13 mg/L, respectively). All compounds exhibited antioxidant activity, with 14 compounds surpassing α-tocopherol (standard) in DPPH radical scavenging. In silico analyses were conducted using molecular docking, drug-likeness data, physicochemical properties, and ADMET parameters to evaluate the potential of the compounds. Molecular docking simulations against the active sites of NADPH oxidase, penicillin-binding protein (bacterial target), and lanosterol 14-alpha demethylase (fungal target) revealed favorable binding energies for the majority of the compounds, indicating good affinity towards the targeted proteins. Overall, the research on novel multifunctional chloroacetamide derivatives is a valuable contribution to the field of biological chemistry and has the potential to lead to the development of new and improved products for a variety of microbes. [ABSTRACT FROM AUTHOR]

Secondary metabolites produced by Bacillus species from marine sources encompass a variety of compounds such as lipopeptides, isocoumarins, polyketides, macrolactones, polypeptides and fatty acids. These bioactive substances exhibit various biological activities, including antibiotic, antifungal, antiviral, and antitumor properties. This study aimed to isolate and identify a particular species of Bacillus from marine water and organisms that can produce bioactive secondary metabolites. Among the 73 Bacillus isolates collected, only 5 exhibited antagonistic activity against various viral and bacterial pathogens. The active isolates were subjected to 16S rRNA sequencing to determine their taxonomical affiliation. Among them, Bacillus tequilensis CCASU-2024-66 strain no. 42, with the accession number ON 054302 in GenBank, exhibited the highest inhibitory potential. It displayed an inhibition zone of 21 mm against Bacillus cereus while showing a minimum zone of inhibition of 9 mm against Escherichia coli and gave different inhibition against pathogenic fungi, the highest inhibition zone 15 mm against Candida albicans but the lowest inhibition zone 10 mm was against Botrytis cinerea, Fusarium oxysporum. Furthermore, it demonstrated the highest percentage of virucidal effect against the Newcastle virus and influenza virus, with rates of 98.6% and 98.1%, respectively. Furthermore, GC-MS analysis was employed to examine the bioactive substance components, specifically focusing on volatile and polysaccharide compounds. Based on these results, Bacillus tequilensis strain 42 may have the potential to be employed as an antiviral agent in poultry cultures to combat Newcastle and influenza, two extremely destructive viruses, thus reducing economic losses in the poultry production sector. Bacteria can be harnessed for the purpose of preserving food and controlling pathogenic fungi in both human and plant environments. Molecular docking for the three highly active derivatives 2,3-Butanediol, 2TMS, D-Xylopyranose, 4TMS, and Glucofuranoside, methyl 2,3,5,6-tetrakis-O-(trimethylsilyl) was carried out against the active sites of Bacillus cereus, Listeria monocytogenes, Candida albicans, Newcastle virus and influenza virus. The data obtained from molecular docking is highly correlated with that obtained from biology. Moreover, these highly active compounds exhibited excellent proposed ADMET profile. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate antioxidative features using 2,2-diphenyl-1-pycrylhydrazyl free radical (DPPH•) scavenging method, bovine serum albumin (BSA)-binding properties with usage of spectrofluorimetric method, proliferative and cyto/genotoxic status by use of chromosome aberration test, and antimicrobial potential using broth microdilution method, followed by resazurin assay of benzyl-, isopropyl-, isobutyl and phenylparaben in vitro. Our results showed that all parabens had significant antiradical scavenger activity compared to p-hydroxybenzoic acid (PHBA) precursor. Higher mitotic index for benzyl-, isopropyl and isobutylparaben (250 µg/mL) in comparison with control was demonstrated. An increase in the frequency of acentric fragments in lymphocytes treated with benzylparaben and isopropylparaben (125 and 250 µg/mL), and isobutylparaben (250 µg/mL) was observed. Isobutylparaben (250 µg/mL) induced higher number of dicentric chromosomes. An increased number of minute fragments in lymphocytes exposed to benzylparaben (125 and 250 µg/mL) was found. A significant difference in the frequency of chromosome pulverization, between phenylparaben (250 µg/mL) and control, was detected. Benzylparaben (250 µg/mL) and phenylparaben (62.5 µg/mL) caused an increase in the number of apoptotic cells, while isopropylparaben (62.5, 125 and 250 µg/mL) and isobutylparaben (62.5 and 125 µg/mL) induced higher frequency of necrosis. Minimum inhibitory concentration (MIC) of tested parabens ranged 15.62–250 µg/mL for bacteria, and 125–500 µg/mL for the yeast. Minimum microbiocidal concentration ranged 31.25 to 500 µg/mL, and 250 to 1000 µg/mL in bacteria and fungi respectively. The lowest MICs for bacteria were observed for phenyl- (15.62 µg/mL) and isopropylparaben (31.25 µg/mL) against Enterococcus faecalis. [ABSTRACT FROM AUTHOR]

A series of quinoline-thiazole appended 1,4-disubstituted 1,2,3-triazole were synthesized by performing Cu(I) catalyzed 1,3-dipolar cycloaddition reaction ("Click" reaction) and fully characterized by various spectral techniques like FTIR, NMR and HRMS. These compounds were evaluated for in vitro antimalarial activity against plasmodium falciparum. All the compounds (7a–7y) exhibited moderate to good activity in comparison to standard drug Quinine. Compound 7r (IC50 0.19 µg/mL) displayed appreciable activity comparable to Quinine (IC50 0.268 µg/mL). Further antimicrobial screening of the synthesized substituted triazoles were also carried out against two gram (+) bacteria (Staphylococcus aureus, Bacillus subtilis), two gram (–) bacteria (Escherichia coli, Klebsiella pneumonia) and two fungi (Candida albicans, Aspergillus niger). Results revealed that compound 7r reflected promising antimicrobial activity among the synthesized library of molecules. Molecular docking studies of broadly active antimalarial disubstituted triazoles 7m and 7r were explored in the active site of enzyme dihydroorotate dehydrogenase (DHODH) to have the probable mode of action. [ABSTRACT FROM AUTHOR]

Antibiotics may induce super-resistant bacteria if they are available in the environment. Therefore, the removal of aqueous nitrofurantoin (NFT), and more importantly, the removal of the remaining antimicrobial activity after treatment, by the photo-Fenton process, was herein studied. Degradation experiments were performed according to an experimental design (0.5% error; factors: concentrations of NFT, Fe3+, and H2O2). Degradation conditions were: 20 mg NFT L−1, 10 mg Fe3+ L−1, and 170 mg H2O2 L−1. Fixed parameters were: 100 mL of the NFT solution, pH 2.5, 15-min stirring, and 25.0 ± 0.5°C. The initial rate constant (k0) and the maximum oxidation capacity (MOC) of the system were 0.61 min−1 and 100%, respectively (R2 = 0.986). 97% of the NFT and 93% of the organic carbon initially present were removed. Five degradation products (DPs) were detected by HPLC-MS and their endpoints estimated by the ECOSAR (ECOlogical Structure–Activity Relationships) 2.0 software. NFT and its DPs presented no toxicity towards Lactuca sativa. The antimicrobial activity (Escherichia coli) of NFT and/or DPs was completely removed in 15 min. Structures were proposed for the detected DPs. In short, the tested advanced oxidation technology (AOP), besides being capable of removing and mineralizing aqueous NFT in a short time, 15 min, also rendered the treated water biologically inactive (no ecotoxicity, no antimicrobial activity). [ABSTRACT FROM AUTHOR]

AbstractThe effect of gamma irradiation upon the bioactive potentials of selected Cucurbitaceae seeds commonly known as Char Magaz was investigated. The seeds were irradiated in triplicate at doses of 1, 5, 10, and 20 kGy gamma rays in a cobalt-60 irradiator. These were extracted with n-hexane, chloroform, ethyl acetate and methanol and the extracts were concentrated by rotary evaporation. The antimicrobial effects of the irradiated and non-irradiated samples against bacterial strains and the fungal strains were assessed by the agar-well diffusion method and the minimal inhibitory concentration technique. The antioxidant activities were determined via 2, 2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and ferric reducing antioxidant power (FRAP) methods. The chloroform extract of cucumber seeds exhibited the greatest zone of inhibition (18.0 mm) against S. aureus. Minimal inhibitory concentrations (MIC) for antibacterial and antifungal activities ranged from 320.0 to 1280 µg/mL, and 0.50 to 16.0 µg/mL, respectively. Seeds exposed up to 10 kGy gamma irradiation increased DPPH and ABTS scavenging activities. Comparatively, all seed extracts showed high antioxidant potentials in the FRAP assay at all doses. The results suggested that gamma irradiation up to 10 kGy enhances bioactivities of the analyzed seeds. [ABSTRACT FROM AUTHOR]

AbstractA new series of 1,3,4-thiadiazole linked to sulfa-azo derivatives via hydrazono-methyl bridge were synthesized via the reaction of methyl ((E)-(sulfa-derivatives)diazenyl) benzylidene)hydrazine-1-carbodithioates 1a-e with ethyl ester and acetyl hydrazonyl halides 2a-d. The chemical structures of the newly 1,3,4-thiadiazoles 3a-t have been clarified considring their elemental and spectral analysis. Antimicrobial activity of the newly 1,3,4-thiadiazoles was determined for Staphylococcus aureus, Escherichia coli, Candida albicans, as well as Aspergillus niger using the cup agar plate diffusion method. Out of the twenty compounds, compounds 3j, 3k, 3l, and 3s with isoxazole sulfonamides were selected for MIC assay. Compound 3j was equipotent with neomycin control drug against all tested strains, while compound 3k was 4-fold higher than neomycin against S. aureus, E. coli, and C. albicans with MIC values of 9.77, 19.53, and 19.53 μg/mL, respectively. Compound 3l was equipotent with neomycin against S. aureus and C. albicans, while it was 2-fold higher than neomycin against E. coli with MIC of 39.06 μg/mL. For 3s, it was less potent than neomycin against all tested microbs with 2-fold and 4-fold less potent. Further scanning electron microscopy (SEM) investigation has been studied to reveal the disruption effect of the selected potent antimicrobial compound (3k) on the intact cells of tested microbs S. aureus, E. coli in addition to C. albicans. Results showed that 3k exhibited a noticeable effect on destroying microbial cell walls. Furthermore, molecular docking study has been done to assess the binding behavior of two most effective compounds 3k and 3l with the target crystal structure of dihydropteroate synthase (PDB: 6CLV for S. aureus) and (PDB: 5U14 for E. coli). Compound 3k was shown to be able to form stable complexes with both target enzymes of dihydropteroate synthase through hydrogen bonding and hydrophobic interactions. [ABSTRACT FROM AUTHOR]

A Cd(II) complex of composition Cd(C11H9CONHO)2 has been synthesized by treating CdCl2 (anhydrous) with potassium 1-naphthaleneacetohydroxamate (C11H9CONHOK) (KHL) in 1:2 molar ratio in MeOH. Various physicochemical studies including elemental analysis, molar conductivity, FTIR, UV-visible,1H and 13C NMR spectroscopic techniques were employed to interpret the structure of the complex. O,O-Coordination has been proposed through the carbonyl and hydroxamic oxygen atoms and a distorted tetrahedral geometry around cadmium is supported by physicochemical and computational studies. Density Functional Theory studies have shown the stability of the complex and predict various structural parameters (bond lengths and angles). Chemical reactivity descriptors and Mulliken charge analysis were also calculated and analyzed. Molecular docking studies were conducted to analyze the interaction of the ligand and complex with two proteins, Escherichia coli Tem1 beta-lactamase (PDB ID = 1BTL) and Alternaria alternata major allergen alt a 1 (PDB ID = 4AUD). Further, the ligand and complex were tested in vitro for their antimicrobial activity against selected microbes such as S. aureus, S. typhi, E. coli, S. flexneri, Rhizoctonia solani, Alternaria alternata, and Fusarium Sambucinum. The complex was more effective against A. alternata, showing inhibition specifically against S. typhi and E. coli. In vitro cytotoxicity studies were conducted on Rhabdomyosarcoma RD cancer cell lines. The results revealed a reduction in cell viability, correlating with increasing concentrations of the compounds, thereby indicating efficient cytotoxic activity. [ABSTRACT FROM AUTHOR]

Ruellia angustiflora is a shrub popularly known as flower of fire, used in traditional medicine as a healing agent. This study aims to verify the presence of characteristics of pharmaceutical interest in extracts from the root, stem and leaves of this species. The ideal time for ultrasound-assisted extraction is 60 min with a solid-liquid ratio of 1% (w/v). The kinetics of the reaction of the extracts with DPPH is biphasic, and IC50 values are related to the total phenolic compounds. Five phenolic compounds were identified in the extracts, where ferulic acid, rutin and quercetin showed to be the main responsible for the antiradical activity. The extracts displayed considerable photoprotective activity, mainly Ra-LE (SPF = 23). Ra-RE showed an inhibition halo similar to erythromycin against Streptococcus pyogenes. Taken together, these data reveal that Ruellia angustiflora is a source of phenolic compounds and has relevant antiradical, photoprotective and antibacterial activities. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare the extraction yields, chemical compositions and antimicrobial activities of essential oils obtained by hydrodistillation (HD) and volatile extracts obtained by supercritical fluid extraction extraction (SFE) from oregano (Origanum onites), lavender (Lavandula angustifolia), sage (Salvia officinalis), anise (Pimpinella anisum) and clove (Syzygium aromaticum). Essential oil compounds (EOCs) of the obtained materials from both techniques (HD and SFE) were determined by GC-MS/FID. Agar well diffusion method was used for the determination of antimicrobial activities on five different foodborne microorganisms (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli Enterococcus faecalis and Klebsiella pneumoniae). According to the results; extraction yields of SFE were found to be higher than HD for all tested aromatic plants. Active ingredient ratios (carvacrol, camphor, anethole, eugenole and linalol) varied depending on the extraction methods. SFE extracts were higher antimicrobial activity than HD essential oils, except clove extract on E. faecalis. [ABSTRACT FROM AUTHOR]

Essential oils isolated from leaves, twigs, fruit bark and seeds of Michelia tonkinensis collected in Muong Nhe Nature Reserve, Dien Bien province were obtained by hydrodistillation with yields of 1.5, 0.42, 0.16 and 4.6% respectively (v/w on dry weight basis). After analysis through GC, GC-MS and 13C NMR, 30, 34, 31 and 13 compounds (representing 96.4%, 96.8%, 97.1% and 99.9% of the whole composition, respectively) were identified in the leave, twig, fruit bark and seed essential oils. The main components were limonene (43.2%) and germacrene D (32.7%) in the leaf oil; limonene (67.1%) and germacrene D (10.4%) in the twig oil; limonene (66%) in the fruit bark oil; and safrole (90%) in the seed oil. Essential oils from the leaves and twigs showed strong inhibition against Staphyloccocus aureus. The fruit bark essential oil exhibited greater antibacterial potential against all 3 tested microorganisms (S. aureus, Escherichia coli and Candida albicans). The essential oil from seed displayed weak antibacterial activity against the three tested microorganisms. [ABSTRACT FROM AUTHOR]

Dialium guineense essential oil possesses various biological and biochemical activities. The present study is based on determination of antimicrobial, anti-diabetic, anti-cholinesterase, anti-biofim, anti-antibiotic resistance modifying activities and anti-quorum sensing potential of essential oil. Chemical compounds in essential oil were recognised by retention indices using gas chromatograph-mass spectroscopy (GC-MS). A total of 45 compounds were present in the essential oil of which 12 are most active. Essential oil of D. guineense showed highest anti-bacterial activity in the form of zone of inhibition, produced 23 mm zone against Staphylococcus aureus and 15 mm against Escherichia coli. D. guineense oil at various concentrations showed excellent anti-diabetic and anti-cholinesterase activities. Since many active compounds were present in D. guineense oil so authors of this study planned to observe effect of D. guineense oil on quorum sensing regulated virulence factors and thus bio-film formation in pathogens Essential oil reduced bio-film formation considerably at all concentrations against E. coli, Staphylococcus aureus and Pseudomonas aeruginosa. Determination of quorum sensing (QS) inhibitory activity was demonstrated by reduction in pyocyanin (73.93%), total protease (68.59%) and chitinase activity (66.18%) in Pseudomonas aeruginosa at 1 mg/mL of D. guineense oil compared to control. Essential oil at all concentrations tested showed synergistic effect. Since essential oil showed anti-microbial, anti-biofilm and quorum sensing regulated anti-pathogenic activities. Based on results mentioned above, it is concluded that bioactive chemicals from D. guineense oil can act as an anti-infective agent by controlling growth, bio-film formation and signalling pathways of pathogenic microbes as well as other diseases. [ABSTRACT FROM AUTHOR]

Peppermint is a perennial herb with high inhibitory power against bacteria because its chemical profile contains menthol and menthone. In this research, peppermint essential oil (PEO) was encapsulated in various levels (0, 2.5, 5, and 10% w/v) in nanofibers (NFs) obtained from zein using an electrospinning technique. SEM, XRD, TGA, and FTIR tests were performed to investigate the characteristics of NFs after producing them. Also, the resultant NFs were evaluated regarding encapsulation efficiency (EE) and antimicrobial properties via disc-diffusion against Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Salmonella enterica. The results indicated that the morphology was tubular, uniform, and free bead. Fiber diameter increased on average by increasing the amount of PEO (p<0.05). XRD results showed that PEO was amorphous in electrospun zein NFs. TGA and FTIR analyses confirmed the presence of PEO in the electrospun fibers. In addition, the FTIR spectrum showed that the zein protein changed its secondary structure because of the PEO. The results of EE showed that an increase in PEO concentration caused a relevant rise in EE (P<0.05). The electrospun NFs containing PEO showed antimicrobial properties against the target bacteria. According to the current research, NFs obtained from zein via electrospinning can be applied suitably as a substrate to encapsulate PEO as a hydrophobic component. [ABSTRACT FROM AUTHOR]

Metal sulfide nanoparticles have recently attracted much attention due to their unique physical and functional properties. Metal sulfide nanoparticles used as optoelectronic and biomedical materials in the past decades are promising for making functional nanocomposite films due to their low toxicity and strong antibacterial activity. Recently, copper sulfide and zinc sulfide nanomaterials have been used to produce food packaging films for active packaging. Metal sulfide nanoparticles added as nanofillers are attracting attention in packaging applications due to their excellent potential to improve mechanical, barrier properties, and antibacterial activity. This review covers the fabrication process and important applications of metal sulfide nanoparticles. The development of metal sulfides reinforcing mainly copper sulfide and zinc sulfide nanomaterials as multifunctional nanofillers in bio-based films for active packaging applications has been comprehensively reviewed. As the recognition of metal sulfide nanoparticles as a functional filler increases, the development and application potential of active packaging films using them is expected to increase. [ABSTRACT FROM AUTHOR]

AbstractWet chemical synthesis was used in this instance to create ZnO@TiO2 core-shell nanoparticles. By examining X-ray diffraction and Selected Area Electron Diffraction patterns, it was determined that the phase formation of prepared nanoparticles was a hexagonal primitive structure of ZnO and Tetragonal bcc structure of anatase phase of TiO2 devoid of impurity peaks. It was discovered that crystallites were 25 nm in size on average. The results of a surface morphology analysis utilizing High-Resolution Scanning Electron Microscopy and High-Resolution Transmission Electron Microscopy show that all of the particles are spherical. The energy dispersive X-ray spectroscopy study provided proof for the existence of core-shell elemental compositions. Fourier-Transform Infrared spectrum revealed the presence of characteristics of metal bonding with oxygen of ZnO and TiO2. UV-visible absorption analysis exhibited absorption peak in the UV region and the band gap energy of ZnO@TiO2 core-shell nanoparticles. The thermal behavior of ZnO@TiO2 core-shell nanoparticles was analyzed by using Thermogravimetric Analysis, Differential scanning calorimetry, and Differential Thermal Analysis techniques. The X-ray photoelectron spectroscopy analysis exhibited the coating of TiO2 (shell) on the surface of ZnO (core) for the formation of a core-shell nanostructure. Due to its extremely small crystallite size, wide surface area, and reduced band gap, the ZnO@TiO2 core-shell sample demonstrated outstanding photocatalytic activity when rhodamine-B dye was photocatalytically degraded in the presence of UV light irradiation. Finally, the antibacterial and antifungal activities of ZnO@TiO2 core-shell nanoparticles were investigated, and it was shown that antifungal activity was superior to antibacterial activity. A suitable material for environmental and biological applications that produced core-shell nanoparticles displayed regulated grain size, outstanding photocatalytic performance, and high antifungal activity. [ABSTRACT FROM AUTHOR]

AbstractFungi-mediated biosynthesis of nanoparticles is a potentially beneficial strategy for large-scale production. In this study, ZnO-NPs were synthesized biogenically using a cell free broth from mycoendophyte Alternaria alternata inhabiting Piper cubeba as a reducer and stabilizer agent. ZnO-NPs appeared to be spherical in transmission electron microscopy, Histogram reveals the nanoparticle size between 20 and 60 nm, and FTIR experiments were employed to analyze the structure, shape, and physicochemical characteristics of the ZnO-NPs. The biosynthesized nanoparticles exhibited an absorption peak at 346 nm in the UV–visible spectrum, which corresponded to the plasmon resonance of ZnO-NPs. The X-ray diffraction spectra of the nanoparticles revealed the formation of crystal planes and hexagonal crystal geometry metal oxides of zinc. In experiments, biosynthesised ZnO-NPs were proven to be exhibit broad spectrum antimicrobial activity. Based on antimicrobial studies bacteria were found to be more susceptible when compare to fungi exhibiting antibacterial activity equal that of co-assayed standard (18–21 mm zone of inhibition). As a result, ZnO-NPs could be mass-produced sustainably, with the potential to be used in a range of biological processes. [ABSTRACT FROM AUTHOR]