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Lab coats are widely used in biohazard laboratories and healthcare facilities as protective garments to prevent direct exposure to pathogens, spills, and burns. These cotton-based protective coats provide ideal conditions for microbial growth and attachment sites due to their porous nature, moisture-holding capacity, and retention of warmth from the user's body. Several studies have demonstrated the survival of pathogenic bacteria on hospital garments and lab coats, acting as vectors of microbial transmission. A common approach to fix these problems is the application of antimicrobial agents in textile finishing, but concerns have been raised due to the toxicity and environmental effects of many synthetic chemicals. The ongoing pandemic has also opened a window for the investigation of effective antimicrobials and eco-friendly and toxic-free formulations. This study uses two natural bioactive compounds, carvacrol and thymol, encapsulated in chitosan nanoparticles, which guarantee effective protection against four human pathogens with up to a 4-log reduction (99.99%). These pathogens are frequently detected in lab coats used in biohazard laboratories. The treated fabrics also resisted up to 10 wash cycles with 90% microbial reduction, which is sufficient for the intended use. We made modifications to the existing standard fabric tests to better represent the typical scenarios of lab coat usage. These refinements allow for a more accurate evaluation of the effectiveness of antimicrobial lab coats and for the simulation of the fate of any accidental microbial spills that must be neutralized within a short time. Further studies are recommended to investigate the accumulation of pathogens over time on antimicrobial lab coats compared to regular protective coats.

Objectives: To evaluate the performance of two rapid antimicrobial susceptibility testing (RAST) methods to determine ceftazidime/avibactam susceptibility directly from blood cultures (BCs)., Methods: A total of 246 Escherichia coli or Klebsiella pneumoniae isolates were tested for ceftazidime/avibactam susceptibility directly from BC bottles using EUCAST RAST and Etest® RAST. Results obtained after 4, 6 and 8 h of incubation were compared with those obtained by reference broth microdilution on pure overnight subcultures., Results: In total, the proportion of readable zones after 4 h of incubation was 96.7% and reached 100% after 6 and 8 h of incubation. EUCAST RAST yielded >98% of categorical agreement (CA) with all reading times. Major error (ME) and very major error (VME) rates were inferior to 3%, for each of the reading times. The proportion of results in the area of technical uncertainty (ATU) was almost similar (3.8%-4.1%) at the different reading times. DET-RAST yielded 97.5%, 98% and 99.6% of CA with readings at 4, 6 and 8 h, respectively. One (0.6%) ME was observed at each reading time, whereas five (5.9%) and four (4.5%) VMEs were observed analysing readings at 4 and 6 h, respectively. No VME was observed with readings at 8 h., Conclusions: EUCAST RAST was accurate to determine ceftazidime/avibactam susceptibility of carbapenemase-producing K. pneumoniae and E. coli directly from BC bottles. DET-RAST has the advantage of determining MIC values and avoiding ATU results but showed to be an accurate method only with reading at 8 h., (© The Author(s) 2022. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study aimed to develop a plasticized starch (PS) based film loaded with chitosan nanoparticles (CNPs, 1, 2, 3, and 4%) as a reinforcing and antibacterial agent. We examined the morphology, biodegradability, mechanical, thermo-mechanical, and barrier properties of the PS/CNPs films. The antimicrobial activity against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria was investigated by colony forming unit (CFU) and disc diffusion methods. A dense structure was obtained for all PS/CNPs films and, thus, their complete biodegradation occurred in more days than neat PS. The increase in the CNPs percentage led to improved mechanical behaviour and barrier properties. PS-CNPs composite films revealed inhibition zones against both E. coli and S. aureus, with the 100% reduction in CFU against S. aureus. The current study exhibited that PS-CNPs films were more effective in inhibiting bacteria growth than neat PS film, confirming the composite films potential application as antimicrobial food packaging., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study, the polyphenol content and the antioxidant and antimicrobial activities of hydroethanolic (MVE) and hydroacetonic (MVA) leaf extracts of Marrubium vulgare L. were examined. The results indicated that the total phenolic content was higher in MVA (112.09 ± 4.77 mg GAE/DW) compared to MVE extract (98.77 ± 1.68 mg GAE/DW). The total flavonoid content was also higher in MVA extract (21.08 ± 0.38 mg QE/g DW) compared to MVE (17.65 ± 0.73 mg QE/g DW). Analysis of the chemical composition revealed the presence of 13 compounds with a total of 96.14%, with the major compound being malic acid (22.57%). Both extracts possess a good total antioxidant activity. DPPH and FRAP assays indicated that the MVE extract possesses a better antioxidant activity, with IC 50  = 52.04  µ g/mL ± 0.2 and EC 50 of 4.51 ± 0.5 mg/mL, compared to MVA extract (IC 50  = 60.57 ± 0.6  µ g/mL and EC 50 of 6.43 ± 0.0411 mg/mL). Moreover, both extracts exhibited strong antimicrobial activity against certain nosocomial strains as indicted by the MIC values, which ranged between 0.93 mg/mL and 10 mg/mL. Taken together, these results reveal the importance of M. vulgare as a natural antioxidant with important antimicrobial activity., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Ibrahim Mssillou et al.)

Transparent materials used for facial protection equipment provide protection against microbial infections caused by viruses and bacteria, including multidrug-resistant strains. However, transparent materials used for this type of application are made of materials that do not possess antimicrobial activity. They just avoid direct contact between the person and the biological agent. Therefore, healthy people can become infected through contact of the contaminated material surfaces and this equipment constitute an increasing source of infectious biological waste. Furthermore, infected people can transmit microbial infections easily because the protective equipment do not inactivate the microbial load generated while breathing, sneezing or coughing. In this regard, the goal of this work consisted of fabricating a transparent face shield with intrinsic antimicrobial activity that could provide extra-protection against infectious agents and reduce the generation of infectious waste. Thus, a single-use transparent antimicrobial face shield composed of polyethylene terephthalate and an antimicrobial coating of benzalkonium chloride has been developed for the next generation of facial protective equipment. The antimicrobial coating was analyzed by atomic force microscopy and field emission scanning electron microscopy with elemental analysis. This is the first facial transparent protective material capable of inactivating enveloped viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in less than one minute of contact, and the methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis . Bacterial infections contribute to severe pneumonia associated with the SARS-CoV-2 infection, and their resistance to antibiotics is increasing. Our extra protective broad-spectrum antimicrobial composite material could also be applied for the fabrication of other facial protective tools such as such as goggles, helmets, plastic masks and space separation screens used for counters or vehicles. This low-cost technology would be very useful to combat the current pandemic and protect health care workers from multidrug-resistant infections in developed and underdeveloped countries.

Objectives: The emergence of multidrug-resistant Neisseria gonorrhoeae (NG) is a major global health threat necessitating response and control measures. NG antimicrobial resistance (AMR) surveillance data from sub-Saharan countries is exceedingly limited. This paper aims to describe the establishment, design and implementation of a standardised and quality-assured gonococcal surveillance programme and to describe the susceptibility patterns of the cultured gonococcal isolates in Kampala, Uganda., Methods: From March 2018 to September 2019, using the WHO Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP) protocol, consecutive males with urethral discharge syndrome were recruited from 10 surveillance sites in Kampala City, Uganda, in collaboration with the Ministry of Health. Males completed a questionnaire and provided a urethral swab specimen. Culture, identification and antimicrobial susceptibility testing (Etest) were performed., Results: Of the 1013 males recruited, 73.1% (740/1013) had a positive Gram stain and 51.1% (n=518) were culture-positive for NG. Using Etest (458 isolates), the resistance to ciprofloxacin was 99.6%. Most isolates were susceptible to azithromycin, cefoxitin and gentamicin, that is, 99.8%, 98.5% and 92.4%, respectively, and all isolates were susceptible to ceftriaxone and cefixime., Conclusions: We established a standardised, quality-assured WHO EGASP. Using Etest, 458 isolates were characterised, with associated epidemiological surveillance data, in 1.5 years, which by far exceed the minimum 100 isolates per year and country requested in the WHO Global GASP, to detect AMR levels with confidence. These isolates with the epidemiological data can be used to develop population level interventions., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Trianthema triquetra Rottl. ex Willed is being used as a herbal remedy for various diseases in India and Pakistan. Still, no scientific data is available about therapeutic potential and phytochemistry of the plant. The aim of the current investigation is to perform GC-MS analysis, antioxidant (total phenolic and flavonoid content, DPPH assay), antimicrobial (disc diffusion assay) and cytotoxic (XTT and RBC's cellular membrane protection assay) studies. Methanolic extract and its fractions (n-hexane, ethyl-acetate, chloroform, n-butanol and water) were investigated for in vitro studies. Results showed that n-butanol fraction exhibited a significant (p<0.05) antioxidant potential (IC50=63.35±0.13 μg/mL) and also possess highest phenolic content (177±4.36 mg/g GAE). Whereas, n-hexane fraction showed highest flavonoid content (14.67±1.53 mg/g QE). 2, 4-Ditert-butyl-6-nitrophenol (26.79%) and Squalene (25.64%) were detected as major components through GC-MS analysis of chloroform fraction, eluted from column chromatography. Moreover, chloroform fraction also exhibited antimicrobial potential. Significant (p<0.05) dose dependent inhibition response on cell growth against CCRF-CEM cell lines was exhibited by methanolic extract. Furthermore, hemolytic potential of methanolic extract was found to be in safe range (2.23%-6.37%). So, it can be inferred that Trianthema triquetra can be exploited as an alternative remedy for cancer, oxidative stress related disorders and various skin diseases.

Investigation of the Red Sea sponge Negombata magnifica gave two novel alkaloids, magnificines A and B ( 1 and 2 ) and a new β-ionone derivative, (±)-negombaionone ( 3 ), together with the known latrunculin B ( 4 ) and 16- epi -latrunculin B ( 5 ). The analysis of the NMR and HRESIMS spectra supported the planar structures and the relative configurations of the compounds. The absolute configurations of magnificines A and B were determined by the analysis of the predicted and experimental ECD spectra. Magnificines A and B possess a previously unreported tetrahydrooxazolo[3,2- a ]azepine-2,5( 3H,6H )-dione backbone and represent the first natural compounds in this class. (±)-Negombaionone is the first β-ionone of a sponge origin. Compounds 1 - 3 displayed selective activity against Escherichia coli in a disk diffusion assay with inhibition zones up to 22 mm at a concentration of 50 µg/disc and with MIC values down to 8.0 µM. Latrunculin B and 16- epi -latrunculin B inhibited the growth of HeLa cells with IC 50 values down to 1.4 µM.

Current study was intended to isolate bioactive compounds from ethyl acetate fraction of Saussurea hypoleuca root extract and evaluation of their antioxidant, antimicrobial and anti-cancerous activities which might be helpful for their chemo preventive potential against selected bacterial strains. Column chromatography was done for isolation of compounds which were characterized on the basis of extensive spectroscopic analysis; Infra-red (IR), Electron Ionization (EI-Positive), Proton Nuclear Magnetic Resonance ( 1 H-NMR) and Carbon Nuclear Magnetic Resonance ( 13 C-NMR). Two compounds were identified, as sesquiterpenes (40mg) and linoleic acid (33mg) from 10 grams of ethyl acetate fraction. Both compounds have shown in vitro antioxidant activity which in regard; 2, 2- diphenyl-1-picrylhydrazyl (DPPH) scavenging potential was high in sesquiterpenes (261.81) as compared to linoleic acid (90.89). The minimum inhibitory concentrations (MIC) of both compounds were evaluated in various bacterial and fungal strains against respective controls. However, in human hepatocellular carcinoma (Hep G2 cell lines) sesquiterpenes exhibited strong anticancer potential than linolenic acid which might be its potential free radical inactivator in MTT assay. This paper directs the ethano medicinal worth of plant root as it possesses bioactive compounds which in our best knowledge these compounds isolated and reported first time from this plant root specie.

Naturally occurring phytochemicals serve as an excellent substitute in synthesizing nanomaterials. A process for the synthesis of silver nanoparticles (AgNPs) from the aqueous leaf extract of naturally occurring Scoparia dulcis is described here. The extracellular formation of AgNPs occurred within few minutes upon incubation of S. dulcis aqueous leaf extract (0.1 mL) (100% extract) with silver nitrate (2 mM AgNO 3 ) at 90 °C for 30 min, is first of its kind work. The appearance of bright yellow color with λ max 420 nm confirm the formation of AgNPs. Zeta potential and X-ray diffraction (XRD) studies reveal stable AgNPs (-22.7 mV) and characteristic spectra for silver. Fourier transform infrared (FTIR) spectroscopy indicate the involvement of carboxyl, amine and hydroxyl groups in the synthetic process. Transmission electron microscopy (TEM) show the spherical nature of AgNPs measuring 3-18 nm in size. Additional characterization using Dynamic light scattering (DLS) revealed the average particle size distribution of AgNPs as around 8.2 nm. Further antimicrobial testing through agar disc diffusion plate method indicated that silver nanoparticles are potentially active against pathogenic bacteria such as Pseudomonas aeruginosa , Escherichia coli , Bacillus subtilis and Staphylococcus aureus and are only optimally active against fungi such as Aspergillus niger and Candida albicans and measurement of minimal inhibition concentration by standard microdilution method. In conclusion, the study suggests that successful synthesis of green nanoparticles (AgNPs) using aqueous S. dulcis leaf extract is simple, rapid, environmentally benign and economical. Moreover, these synthesized silver nanoparticles showed antimicrobial activity.

Recent medical strategies rely on the search for effective antimicrobials as surface coatings to prevent and treat infections in humans and animals. Biosurfactants have recently been shown to have properties as antiadhesive and antibiofilm agents. Sophorolipids in particular are biosurfactant molecules known to act as therapeutic agents. This study aimed to evaluate antimicrobial properties of sophorolipids in medical-grade silicone discs using strains of clinical relevance. Sophorolipids were produced under fed batch conditions, ESI-MS analyses were carried out to confirm the congeners present in each formulation. Three different products were obtained SLA (acidic congeners), SL18 (lactonic congeners) and SLV (mixture of acidic and lactonic congeners) and were tested against Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 10145 and Candida albicans IHEM 2894. All three congener mixtures showed a biofilms disruption effect (> 0.1 % w/v) of 70 %, 75 % and 80 % for S. aureus, P. aeruginosa and C. albicans, respectively. On pre-coated silicone discs, biofilm formation of S. aureus was reduced by 75 % using SLA 0.8 % w/v. After 1.5 h the inhibition of C. albicans attachment was between 45-56 % whilst after 24 h incubation the percentage of inhibition for the cell attachment increased to 68-70 % when using SLA 0.8 % w/v. Finally, in co-incubation experiments SLA 0.05 % w/v significantly reduced the ability of S. aureus and C. albicans to form biofilms and to adhere to surfaces by 90-95 % at concentrations between 0.025-0.1 % w/v. In conclusion sophorolipids significantly reduced the cell attachment of both tested strains which suggests that these molecules could have a potential role as coating agents on medical grade silicone devices for the preventions of Gram positive bacteria and yeast infections., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In this study, natural waste of marine corals was calcined to prepare an antimicrobial agent. Energy-dispersive X-ray fluorescence spectroscopy showed that the major element and compound of calcined corals were Ca and CaO, respectively, while X-ray photoelectron spectroscopy revealed the occurrence of more than one oxygen species (O 1s ) on the surface of calcined corals, which was ascribed to the presence of MgO. Scanning electron microscopy imaging showed that calcined corals had a rough surface and an irregular shape, and the particle size distribution indicated that the average particle size of the calcined corals was 7.3 μm. The calcined corals exhibited large zones of inhibition against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria as well as a fungus (Penicillium sp.), in the antimicrobial tests using well diffusion method. Notably, as a membrane-active and species-specific agent, pronounced antimicrobial activity for calcined corals was observed against S. aureus. Our newly developed bioactive calcined corals could be the potential antimicrobial agents in medical, biological, and food packaging applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, for developing a scaffold for tissue engineering from fish processing wastes, a hierachial collagen/gelatin/chitosan novel porous scaffold was fabricated using blends of collagen and gelatin extracted from the skins of Marine big eye snapper Priacanthus humrur. Scaffolds were developed by mechanical spinning of chitosan and by mixing of collagen and gelatin solutions followed by freeze drying and subsequent crosslinking of polymers. The scaffolds were evaluated for rheological properties - porosity, apparent density and swelling capacity to assess their mechanical property.Gelatin/chitosan composition shown very high porosity(81.02%) and incorporation of collagen shown higher density in Collagen/gelatin/chitosan scaffolds (0.0522g/cm 3 ) and collagen/chitosan scaffolds (0.0468 g/cm 3 ).Morphology of the prepared scaffolds were analyzed by Scanning Electron Microscopy which showed reduced pore size of 10 to 20μ in Collagen/gelatin/Chitosan composite, 5 to 10μ in gelatin/chitosan composites and 2-5μ in collagen/chitosan composites. FTIR analysis showed intense peaks ranging 1120 -11267 cm -1 in the three different scaffolds that are denoted as CH groups. In-vitro antioxidant investigation through DPPH assay showed that the composite 3 in 1 mg/ml concentration exhibited higher antioxidant potential (70%). In contrast, ABTS scavenging assay identified composite1 in 1 mg/ml had good antioxidant activity with highest percentage of inhibition (29.5%). The scaffolds were also evaluated for anti microbial properties through disc diffusion assay. The results showed maximum inhibition- 14 mm, 12 mm and 14 mm for 200 μg of the sample for collagen/chitosan, gelatin/chitosan and collagen/gelatin/chitosan scaffolds respectively towards E.Coli and 20 mm, 20 mm and 24 mm towards S.aureus. The zone of inhibition against E. coli and S. aureus for the three scaffolds was comparatively lower and that could be due to the presence of chitosan. The findings of the study indicates that the bioscaffolds are expected to have wide application in tissue engineering., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study compared Neo-Sensitabs with Oxoid paper disks using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) disk diffusion antimicrobial susceptibility test on Mueller-Hinton agar. The EUCAST-recommended quality control strains (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 29213 and Enterococcus faecalis ATCC 29212) (Part I) and clinical isolates (Part II) were investigated. In Part I of the study, 27 combinations of antimicrobial agents were tested on four quality control strains repeatedly up to 60 times and zone diameters of tablets and disks were compared. In Part II of the study, 351 clinical isolates were included to cover a broad range of species, as well as resistance mechanisms. In Part I, four major deviations (>1 mm outside quality control ranges) were observed with Neo-Sensitabs. In one case with P. aeruginosa ATCC 27853 (meropenem), there was a corresponding major deviation (2 mm) with the Oxoid disk. The three remaining major deviations with Neo-Sensitabs were observed with meropenem (2 mm) in E. coli ATCC 25922 and with ciprofloxacin (2 mm) and gentamicin (3 mm) in P. aeruginosa ATCC 27853. For Oxoid disks, there were only minor deviations (=1 mm outside quality control ranges) in these three cases. In Part II, there were six discrepancies, susceptible versus resistant, in 3,533 comparisons between the two methods with the clinical isolates. The Rosco Neo-Sensitabs appear to be a possible alternative to Oxoid paper disks for EUCAST disk diffusion antimicrobial susceptibility testing on Mueller-Hinton agar.

The aim of this study is to investigate for the first time in vitro antimicrobial and antimutagenic activities of Schiff bases included the azomethine group. Antimutagenic activity was evaluated by micronucleus (MN) assay. These group have been examined for antibacterial activity against pathogenic strains, Staphylococcus aureus, Escherichia coli, Salmonella typhi H, Brucella abortus, Micrococcus luteus, Bacillus cereus, Pseudomonas aeroginosa and antifungal activity against Candida albicans and Saccharomyces cerevisiae. The results of MN showed that Schiff bases ((E)-N-(4-chlorophenyl)-1-(5-nitrothiophen-2-yl)methanimine ; (E)-N-(2,4-dichlorophenyl)-1-(5-nitrothiophen-2-yl) methanimine) different concentrations decreased the toxic effects of Aflatoxin B1. Especially, high concentration (20μM) of (E)-N-(4-chlorophenyl)-1-(5-nitrothiophen-2-yl)methanimine (compound 1) has strong antimutagenic activity. In our in vitro test systems, it was observed that Schiff bases had antimutagenic effects on human lymphocytes. On the other hand these compounds were also found to possess antimicrobial activity against some test bacteria and yeast. The antimicrobial test results of these Schiff bases included the azomethine group exhibited better activity than some known antibiotics. In particular, Compound 1 were more potent bactericides than all of the substances synthesized. In conclusion, this Schiff bases included the azomethine group can be use pharmacy industries as recognized with their noncytotoxic, antimicrobial and antimutagenic features.

Thymus marschallianus Willd. is a Lamiaceae species spread in a large variety of habitats worldwide. The aim of the present research was to analyse two different samples belonging to this species, one obtained from the spontaneous flora and one from culture. The total polyphenols, flavonoids, and phenolic acid contents were spectrophotometrically determined. Qualitative and quantitative analysis of polyphenols was performed by an HPLC-DAD-ESI (+)-MS method. For the antibacterial assay, the well-diffusion and the broth microdilution methods were used. Analysis of polyphenols revealed for both samples the presence of flavonoids like luteolin, quercetin, apigenin and their derivatives, but also of rosmarinic acid and methyl-rosmarinate. Differences regarding the amount of these compounds were emphasized. Significantly larger amounts of flavonoids were found for the sample harvested in the spontaneous flora, while for the rosmarinic acid, larger amounts were found for the cultured sample. Both samples displayed promising antibacterial activity, particularly towards Gram positive organisms. T. marschallianus represents, therefore, a rich source of polyphenolic compounds that prove its promising potential as a medicinal species., Competing Interests: The authors declare no conflict of interest.

During the last years, the food industry is working on the replacement of high energy methodologies with more sustainable techniques for the encapsulation of natural preservatives, in order to enhance their effectiveness as food additives. In the present study, nisin, an antimicrobial agent, was encapsulated in essential oil-containing microemulsions. More specifically, rosemary, thyme, oregano, and dittany essential oil-containing microemulsions were formulated to encapsulate nisin enhancing the system's overall antimicrobial activity. The systems were investigated for the interfacial properties and size of the surfactants' monolayer using electron paramagnetic resonance spectroscopy and dynamic light scattering. Subsequently, nisin-loaded microemulsions were tested for their antimicrobial activity against Lactococcus lactis, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus, using the well diffusion assay. Finally, this technique was validated by a killing assay. Overall, this study provides important information on the antibacterial activity of nisin-loaded nano-carriers enhanced by essential oils, in relation to the microemulsions' structure., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Antimicrobial biopolymers provide a biodegradable, sustainable, safe, and cheap approach to drug delivery and wound dressing to control bacterial infection and improve wound healing respectively. Here, we report a one-step method of making antimicrobial alginate polymer from sodium alginate and aqueous extract of Wakame using antibiotic aminoglycosides. Thin layer chromatography of commercially available sodium alginate and Wakame extract showed similar oligosaccharide profiles. Screening of six aminoglycosides showed that kanamycin disulfate and neomycin sulfate produces the highest amount of biopolymer; however, kanamycin disulfate produces the most malleable and form fitting biopolymer. Image texture analysis of biopolymers showed similar quantification parameters for all the six aminoglycosides. Weight of alginate polymer as a function of aminoglycoside concentration follows a growth model of prion protein, consistent with the aggregating nature of both processes. Slow release of antibiotics and the resulting zone of inhibition against E. coli DH5α were observed by agar well diffusion assay. Inexpensive method of production and slow release of antibiotics will enable diverse applications of antimicrobial alginate biopolymer reported in this paper., Competing Interests: The authors have declared that no competing interests exist.

Because of their antibacterial activity, silver nanoparticles (AgNPs) have been explored in biomedical applications. Similarly, nitric oxide (NO) is an important endogenous free radical with an antimicrobial effect and toxicity toward cancer cells that plays pivotal roles in several processes. In this work, biogenic AgNPs were prepared using green tea extract and the principles of green chemistry, and the NO donor S-nitrosoglutathione (GSNO) was prepared by the nitrosation of glutathione. To enhance the potentialities of GSNO and AgNPs in biomedical applications, the NO donor and metallic nanoparticles were individually or simultaneously incorporated into polymeric solid films of poly(vinyl alcohol) (PVA) and poly(ethylene glycol) (PEG). The resulting solid nanocomposites were characterized by several techniques, and the diffusion profiles of GSNO and AgNPs were investigated. The results demonstrated the formation of homogeneous PVA/PEG solid films containing GSNO and nanoscale AgNPs that are distributed in the polymeric matrix. PVA/PEG films containing AgNPs demonstrated a potent antibacterial effect against Gram-positive and Gram-negative bacterial strains. GSNO-containing PVA/PEG films demonstrated toxicity toward human cervical carcinoma and human prostate cancer cell lines. Interestingly, the incorporation of AgNPs in PVA/PEG/GSNO films had a superior effect on the decrease of cell viability of both cancer cell lines, compared with cells treated with films containing GSNO or AgNPs individually. To our best knowledge, this is the first report to describe the preparation of PVA/PEG solid films containing GSNO and/or biogenically synthesized AgNPs. These polymeric films might find important biomedical applications as a solid material with antimicrobial and antitumorigenic properties.

Serial twofold dilution methods are most commonly used to identify the antimicrobial activities of antibiotics. This can be achieved by different methods like broth dilution or agar dilution. Though these methods are simple, they can be influenced by various experimental factors and result in discrepancy. The following protocol has been validated for Acinetobacter species, including A. baumannii. It is important to include appropriate control strains to determine the minimum inhibitory concentration values and to compare the experiment results.

Sulfonamides, being the member of the oldest anti-microbial group of compounds possess wide anti-microbial activities and are effective against pathogenic strains of gram-positive and gram-negative bacteria. They are widely used in the treatment of various infectious diseases e.g. malaria, urinary tract infections, respiratory tract infections etc. Based on their effectiveness against most of the bacteria, two novel sulfonamides (N-(2-methoxy phenyl)-4-methylbenzenesulfonamide and N-ethyl-4-methyl-N-(3-methyl phenyl)benzenesulfonamide) were synthesized. The compounds were characterized by FT-IR and elemental analyzer. Their anti-microbial activity was assessed and observed against gram-positive and gram-negative bacteria using disc diffusion method. They showed good anti-microbial activities.

The inhibitory effects of essential oils as well as chloroformic extracts of Thymus vulgaris, Thymus serpyllum, Salvia officinalis and Pimpinella anisum grown in Ash-shoubak region-south of Jordan and their possible individual phytochemical constituents was screened against pathogenic clinical and standard strains of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The bioassay employed was the agar well diffusion method. The essential oils and chloroformic extracts of T. vulgaris and T. serpyllum were the most effective against the tested strains of bacteria. Clinical and standard strains of S .aureus and P. aeruginosa were uninhibited by S. officinalis essential oils. P. aeruginosa tested strains were also resistant to P. anisum essential oils. For almost all bacterial strains, the highest antibacterial effect of oils was obtained with the highest tested dose (15 μl). Chlorformic extracts of S. officinalis showed small activity against standard and clinical E. coli strains and were not effective to inhibit strains of P. aeruginosa and S. aureus. Chloroformic extracts obtained from P. anisum and applied at 300 μg/cm(2) slightly inhibited E. coli, but moderately inhibited S. aureus. It is shown from the results that the antibacterial effects of the individual components varied depending upon their chemical structure, functional groups and configuration as well as doses used. This study showed the beneficial effects of the essential oils of T. serpyllum and T. vulgaris grown in Ash-shoubak in inhibiting the growth of microbes and the implications this could have in pharmacy and food technology.

The antimicrobial activities of crude methanolic extract of leaves of Acacia nilotica L., Albizia lebbeck L. and Mimosa himalayana Gamble belonging to family mimosaceae were investigated in this research work. Antibacterial activity was studied by agar well diffusion method against one gram-positive Bacillus subtilis and three gram-negative Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumonia. Crude extract of all plants showed best activity against gram-negative bacterial strains while minor inhibition zones were found against gram positive bacterial strains. Antifungal activity of crude plant extract was screened by agar tube dilution method against Aspergillus nigar and Aspergillus flavus. These results showed that these plants extracts have potential against bacterias, while against fungi their activity is not much effective.

Background: Infectious complications following mesh implantation for abdominal wall repair appear in 0.7 up to 26.6% of hernia repairs and can have a detrimental impact for the patient. To prevent or to treat mesh-related infection, the scientific community is currently developing a veritable arsenal of antibacterial meshes. The numerous and increasing reports published every year describing new technologies indicate a clear clinical need, and an academic interest in solving this problem. Nevertheless, to really appreciate, to challenge, to compare and to optimize the antibacterial properties of next generation meshes, it is important to know which models are available and to understand them., Purpose: We proposed for the first time, a complete overview focusing only on the in vitro and in vivo models which have been employed specifically in the field of antibacterial meshes for hernia repair., Results and Conclusion: From this investigation, it is clear that there has been vast progress and breadth in new technologies and models to test them. However, it also shows that standardization or adoption of a more restricted number of models would improve comparability and be a benefit to the field of study.

Social insects are frequently observed in symbiotic association with bacteria that produce antimicrobial natural products as a defense mechanism. There is a lack of studies on the microbiota associated with stingless bees and their antimicrobial compounds. To the best of our knowledge, this study is the first to report the isolation of Paenibacillus polymyxa ALLI-03-01 from the larval food of the stingless bee Melipona scutellaris. The bacterial strain was cultured under different conditions and produced (L)-(-)-3-phenyllactic acid and fusaricidins, which were active against entomopathogenic fungi and Paenibacillus larvae. Our results indicate that such natural products could be related to colony protection, suggesting a defense symbiosis between P. polymyxa ALLI-03-01 and Melipona scutellaris.

Objectives: Although Corynebacterium spp. are part of the microbiota of the skin and mucous membranes, human infections caused by Corynebacterium spp. have been reported and the multidrug resistance pattern of the recovered isolates was emphasised. Due to the usefulness of disk diffusion in daily practice, the purpose of this study was to compare disk diffusion with agar dilution to determine disk diffusion breakpoints and to review the antimicrobial susceptibility of the most frequent Corynebacterium spp. isolated in clinical samples., Methods: Susceptibility to 20 antimicrobial agents of 143 Corynebacterium spp. isolates recovered from relevant clinical samples was determined. Comparison between the disk diffusion and agar dilution methods for eight antimicrobial agents was performed to establish new breakpoints using simple linear regression analysis., Results: All of the isolates tested were susceptible to vancomycin, minocycline and linezolid. A typical susceptibility profile to β-lactam antibiotics among the different species included was not observed. Almost all isolates showed resistance to macrolides and lincosamides. Using a simple linear regression method, it was possible to establish breakpoints for penicillin, erythromycin, clindamycin, gentamicin and ciprofloxacin. However, the low correlation coefficient obtained for vancomycin, minocycline and trimethoprim/sulfamethoxazole did not allow establishment of breakpoints for the disk diffusion method., Conclusion: The disk diffusion method could only be used to evaluate susceptibility to penicillin, erythromycin, clindamycin, gentamicin and ciprofloxacin. These data show that the presence of a Corynebacterium spp. isolate in a clinical sample demands the performance of antimicrobial susceptibility testing since the susceptibility profile is not predictable., (Copyright © 2018 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Silver nanoparticles were prepared through eco-friendly, cost effective, bio-mediated technique using anaerobically digested Parthenium hysterophorous digested slurry (PDS) for the first time. The synthesized nanoparticles were characterized through different techniques such as UV-Vis spectrophotometer for optical properties; X-ray diffractometer (XRD), high resolution transmission electron spectroscopy (HR-TEM) and Fourier Transform Infra Red (FTIR) Spectroscopy for structural property investigations. It was observed that the prepared silver nanoparticles were crystallized in face centered cubic crystal structure with an average particle size of 19 nm as confirmed from XRD. Also HR-TEM studies reveal the formation of nano-sized silver particles with face centered cubic nano structure. In addition, absorption spectra exhibit Surface Plasmon Resonance (SPR) which suggests the formation of silver nanoparticles. FTIR results show the presence of different characteristic functional groups and their stretching / bending vibrations in turn responsible for the bioreduction of silver ions in Parthenium digested slurry. Further investigations on antimicrobial activity were done by subjecting the synthesized silver nanoparticles on E-coli and Pseudomonas as marker organisms for the group of gram negative bacteria by well plate method on enrichment media. The result obtained shows a clear zone of inhibition confirming the antibacterial activity. Overall, the investigated results confirm the biosynthesized silver nanoparticles are potential candidates for antimicrobial activity applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In modern era, the great interest and demand among chemists and researchers for metal nanoparticles is increasing in the application of biomedical fields, textiles, cosmetics and various sectors. Consequently, the present study reports an eco-friendly, cost-effective, rapid and easy method to produce environment-friendly metal nanoparticles to prevent exhaustion of metal resources. In this context, gold and silver metal nanoparticles were green synthesized using the Root Extract of Coleous forskohlii (RECo) as capping and reducing agent. The synthesized gold (GNPs) and silver nanoparticles (SNPs) were characterized using UV-Visible spectrophotometer, High-resolution transmission electron microscopy (HR-TEM), Particle size analysis (PSA), Fourier-transform infrared spectroscopy (FT-IR) and X-Ray Diffractometer (XRD). Their clinical importance was analysed using anti-oxidant assay (DPPH - 2,2-diphenyl-1-picrylhydrazyl and Phosphomolybdenum PMA) and cytotoxicity (MTT assay) against HEPG2 (liver cancer cell lines). Further, the antimicrobial activity against two microorganisms were tested using disc diffusion method against Proteus vulgaris pathogen and Micrococcus luteus pathogen. RECo-GNPs and SNPs were found to be stable in aqueous medium for a longer time and exhibited favorable anti-oxidant, anti-bacterial and anti-cancer activity. The phytoconstituents present in the root extract of Coleous forskohlii was elucidated using GC-MS analysis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The mathematical model was established to determine the diameter of inhibition zone of the walnut extract on the twelve bacterial species. Type of extraction, concentration, and pathogens were taken as input variables. Two models were used with the aim of designing this system. One of them was developed with artificial neural networks (ANN), and the other was formed with multiple linear regression (MLR). Four common training algorithms were used. Levenberg-Marquardt (LM), Bayesian regulation (BR), scaled conjugate gradient (SCG) and resilient back propagation (RP) were investigated, and the algorithms were compared. Root mean squared error and correlation coefficient were evaluated as performance criteria. When these criteria were analyzed, ANN showed high prediction performance, while MLR showed low prediction performance. As a result, it is seen that when the different input values are provided to the system developed with ANN, the most accurate inhibition zone (IZ) estimates were obtained. The results of this study could offer new perspectives, particularly in the field of microbiology, because these could be applied to other type of extraction, concentrations, and pathogens, without resorting to experiments., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In recent years, biosynthesis of nanoparticles has received considerable attention due to the growing need to develop clean and nontoxic chemicals, low-cost approaches, eco - friendly solvents and renewable materials. In the current study, the biosynthesis of TiO 2 nanoparticles (TiO 2 NPs) was attained by a chemical and biosynthesized method by using the aqueous leaf extract of Trigonella foenum-graecum (TF-TiO 2 NP). TiO 2 NPs were characterized by FTIR, UV, XRD, HR-TEM and HR-SEM methods. The X-ray diffraction displayed the existence of TF-TiO 2 NPs which is confirmed by the incidence of peaks at 25.28 corresponds to 101 anatase form. HR-SEM perceptions revealed that synthesized TiO 2 NPs were spherical in shape and the size of individual nanoparticles as well as a few aggregates was found to be 20-90 nm. The antimicrobial activities of biosynthesized nanoparticles (TF-TiO 2 NPs) were examined using Kirby-Bauer method. The TF-TiO 2 nanoparticles showed significant antimicrobial activity against all the tested microorganisms., (Copyright © 2018. Published by Elsevier Ltd.)

The new 1-(4-(3-(aryl)acryloyl)phenyl)-1H-pyrrole-2,5-diones (5a-g) were prepared from 4'-aminchalcones (3a-g) and screened for biological activities. All compounds (3a-g and 5a-g), except 3d and 3e displayed good cytotoxic activities with IC 50 values in the range of 7.06-67.46 μM. IC 50 value of 5-fluorouracil (5-FU) was 90.36 μM. Moreover, most of compounds 5a-g showed high antibacterial activity with 8-20 mm of inhibition zone (19-25 mm of Sulbactam-Cefoperazone (SCF)). In addition, they showed good inhibitory action against acetylcholinesterase (AChE), and human carbonic anhydrase I, and II (hCA I and hCA II) isoforms. Also, these compounds demonstrated effective inhibition profiles with Ki values of 426.47-699.58 nM against hCA I, 214.92-532.21 nM against hCA II, and 70.470-229.42 nM against AChE. On the other hand, acetazolamide, clinically used drug, showed a Ki value of 977.77 ± 227.4 nM against CA I, and 904.47 ± 106.3 nM against CA II, respectively. Also, tacrine inhibited AChE showed a Ki value of 446.56 ± 58.33 nM.

The increasing demand for bio-based materials to be used in food packaging has stimulated the development of novel, environmentally-friendly edible films. Antimicrobial films were developed by incorporating different levels of clove bud essential oil (0.5%, 1.0%, and 1.5%) into the citrus pectin in order to modify the functional properties of the films. Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry analysis (DSC) and X-ray diffraction (XRD) were performed, together with the determination of physical, optical, mechanical, antioxidant and antimicrobial properties of pectin emulsified films. The inclusion of oil significantly enhanced the water barrier properties of the films. Addition of oil leads to more opaque films with relatively heterogeneous microstructure, resulting in an increase in film opacity. The composite films were more resistant to breakage and more flexible than the control films. Differential scanning calorimetry (DSC) demonstrated that films incorporating CEO exhibited improved heat stability with slightly higher degradation temperature, compared with control films. The inhibitory effect of pectin films with CEO was also evaluated on three common foodborne bacteria. These results revealed that clove oil has a good potential to be incorporated into citrus pectin to make antimicrobial edible films or coatings for various food applications., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Oliveria decumbens as a valuable medicinal plant is extensively used in traditional medicine. clinical and standard strains causing infection resistance to antimicrobial agents, is one of the important problems in medicine. The aim of this study was to investigate the antibacterial activities and phytochemical analysis of Oliveria decumbens essential oil on the growth of some clinical and standard strains causing infection (Pseudomonas aerogenes, Escherichia coli, Streptococcus pyogenes and Staphylococcus epidermidis). Oliveria decumbens essential oil composition was identified by gas chromatography/mass spectrometry. Phytochemical analysis (alkaloids, saponins, flavone and phenolic) essential oil of the Oliveria decumbens were appraised based on qualitative methods. Several methods (disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)) were used to appraise the antibacterial activity of the Oliveria decumbens essential oil. Thymol (28.45%) was the major compound of Oliveria decumbens essential oil. The total phenolics content (TPC) of the essential oil positively correlated with antioxidant activity (AA). The TPC and AA of Oliveria decumbens essential oil was equal to 92.45 ± 0.70 μg GAE/mg and 164.45 ± 1.20 μg/ml, respectively. The MIC of Oliveria decumbens essential oil ranged from 1 to 8 mg/ml depending on the type of bacteria (clinical and standard strains). The MBC of Oliveria decumbens essential oil varied from 1 mg/ml to 16 mg/ml. The smallest inhibition zone diameter (IZD) on different Oliveria decumbens essential oil concentrations on P. aeruginosa. Results indicate that Oliveria decumbens essential oil can prove to be an important source of AA and antibacterial and may be used for the treatment of infection diseases., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This study analyzed nanostructured silver vanadate (AgVO3) films on certain substrate surfaces found in dental implant devices in order to see if these films promote antimicrobial activity. Enamel and glaze vehicles were used to apply the nanomaterial (0.0% [control], 2.5%, 5.0%, and 10.0% concentrations) on 3 substrates (280 specimens per substrate): polytetrafluoroethylene (PTFE), polyacetal, and acrylic resin. An agar diffusion method was performed in triplicate to determine the antimicrobial activity against 8 microorganisms. Physical behavior and morphologic properties were also analyzed. The growth of Pseudomonas aeruginosa, Escherichia coli, Streptococcus mutans, Enterococcus faecalis, and Staphylococcus aureus was inhibited with the application of AgVO3. For Candida albicans, Porphyromonas gingivalis, and Prevotella intermedia, no antimicrobial activity was observed. Except for S mutans, the type of substrate did not influence the microbiologic results. The glaze showed greater antimicrobial efficacy against S aureus, E faecalis, and S mutans than did the enamel vehicle (P < 0.05). Films with 10% AgVO3 showed greater antimicrobial activity (P < 0.05). The choice of substrate or vehicle did not influence the surface roughness (P > 0.05); however, the application of 10% AgVO3 caused greater surface change (P < 0.05). The application of the nanomaterial did not influence the surface hardness of substrates when compared with the control group (P > 0.05). The use of the glaze as a vehicle provided higher hardness values (P < 0.05).

In this experimental study, the Allium essential oil (AHEO) was extracted through the hydrodistillation method. AHEO components were identified through gas chromatography/mass spectrometry (GC/MS), and its antioxidant properties and total phenolic content were examined through the methods of 2,2-diphenyl-1-picrylhydrazyl (DPPH), ß-carotene/linoleic acid inhibition and Folin-Ciocalteu, respectively. The antimicrobial effect of AHEO was evaluated on Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Streptococcus pyogenes, and Candida albicans through the methods of well diffusion, disk diffusion, minimum inhibitory concentration, and minimum bactericidal/fungicidal concentration. Phytochemical constituents (alkaloids, tannins, saponins, flavone and glycosides) were evaluated. 5-chloroorcylaldehyde with a percentage of 45.6% was the major compound of AHEO. Increasing concentration of AHEO had a significant effect (p ≤ 0.05) on inhibition zone diameter. The MICs of the AHEO varied from 0.25 mg/ml to 2 mg/ml. The MBCs/MFCs of the AHEO varied from 0.25 mg/ml to 4 mg/ml. The results of phytochemical screening of AHEO showed the existence of alkaloids, tannins, saponins, flavone and glycosides. There was also little difference between disk diffusion and well diffusion methods, and the data was well distributed throughout the X and Y components., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In the present study, green synthesis of silver nanoparticles (AgNPs) is demonstrated using medicinal herb Swertia paniculata extract. The plant extract acted both as reducing and capping agents during synthesis process, where silver nitrate was used as silver source. Subsequent analysis revealed that particles had size range between 31 and 44 nm and were spherical in shape. Among reaction parameters, temperature and time had significantly influenced the synthesis reaction. Also, synthesized nanoparticles were found stable up to 90 days. Further, antimicrobial activity against gram negative and gram positive bacterial strains was done and results showed that synthesized AgNPs had better antimicrobial activity against Pseudomonas aeruginosa, Klebsiella pneumoniae under standard incubation conditions. Study shows that these particles can be very promising in biomedical applications in future., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Various antimicrobial agents are widely used in the therapy of oral inflammatory diseases. However, their side effects and the appearance of drug resistance justify research on natural antimicrobial agents to target oral pathogens that are safe for the host. In the present study, antimicrobial properties of mastic extract on commensal and pathogenic oral bacteria, as well as its possible cytotoxic effect toward cells of epithelial and mesenchymal origin, were evaluated and compared with the common antimicrobial agents hydrogen peroxide (H 2 O 2 ) and chlorhexidine digluconate (CHX)., Methods: Oral and periodontal pathogens (Porphyromonas gingivalis, Streptococcus mutans [Sm], Streptococcus oralis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, and Prevotella nigrescens) were treated with different concentrations of mastic extract, 3% H 2 O 2 , and 0.2% CHX, and evaluated with an agar diffusion test. The cytotoxic effect of mastic extract was tested on four cell lines of epithelial and mesenchymal origin (HaCaT, SaOS-2, MC3T3-E1, periodontal ligament [PDL] cells) by neutral red and 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay., Results: Mastic extract led to significantly (P ≤0.016) increased inhibition of the tested periodontal pathogens compared with H 2 O 2 . No effect of mastic extract was observed on Sm. Mastic extract showed beneficial effects on cell viability because viability values of tested cells were significantly (P ≤0.016) lower for cells treated with CHX and H 2 O 2 compared with mastic extract-treated cells after stimulation for 2, 4, and 6 hours., Conclusion: The present data demonstrate mastic extract's inhibition of periodontal pathogens, as well as beneficial effects on cell viability, compared with H 2 О 2 , suggesting that it could be considered an alternative antibacterial agent in the prevention of periodontal disease.

Objectives: The aim of this study was to validate the use of LML antimicrobial gradient strips for quantitative determination of carbapenem susceptibility in Enterobacteriaceae., Methods: A total of 95 non-redundant Enterobacteriaceae strains isolated during 2012-2014 were used for this validation study. Initially, LML antimicrobial gradient strips were validated for their performance in comparison with the agar dilution method. The test strip was then validated in comparison with broth microdilution (BMD) and Etest with 24 selected strains using the same inocula and other laboratory parameters., Results: The LML strip showed 83%, 68% and 86% essential agreement (within ±1 log 2 dilution) with the reference methods of agar dilution, BMD and Etest, respectively; furthermore, essential agreement was >90% within ±2 log 2 dilution. Categorical agreement was ≥87% with all reference methods according to Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints. However, the meropenem strip requires performance improvements to fulfil US Food and Drug Administration (FDA) and International Organization for Standardization (ISO) requirements for an antimicrobial susceptibility test device., Conclusions: In LML antimicrobial gradient strip minimum inhibitory concentrations (MICs) were comparable with Etest MICs and it might serve as a reasonable, cost-effective alternative to Etest for quantitative determination of carbapenem susceptibility in Enterobacteriaceae., (Copyright © 2016 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.)

Natural extracts (anthocyanins, tannin, anatto, curcuma and olive leaf extracts) were encapsulated within a silica network by acid or base-catalyzed sol-gel methods. The nominal encapsulated contents were between 2.5 and 50wt.-%. The resulting materials were characterized by Fourier transform infrared spectroscopy, diffuse reflectance in the UV region, nitrogen adsorption/desorption porosimetry and small angle X-ray scattering. Encapsulated anthocyanin and tannin afforded inhibition zones between 9-21mm towards Staphylococcus aureus, Escherichia coli, Bacillus cereus, Candida sp. and Aspergillus niger, which was comparable to the free bioactive material in which the inhibition zones were between 10 and 22mm. Anthocyanin exhibited high antioxidant activity in the free state, while tannin showed good antioxidant activity both in its free state and in its encapsulated form. Antimicrobial and antioxidant activities were shown to be dependent on the textural characteristics of the encapsulated materials., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To determine the current trend of antimicrobial susceptibility of typhoidal Salmonellae., Study Design: Descriptive cross-sectional study., Place and Duration of Study: The study was carried out in the Department of Microbiology, PNS Shifa Hospital, Karachi, from January 2014 to December 2015., Methodology: Blood culture samples received from the wards and outpatient departments were included. Isolates of Salmonella were dealt with standard microbiological procedures. The antimicrobial sensitivity against the typhoidal Salmonellaewas determined using Kirby-Bauer disc diffusion method as per the guidelines of Clinical and Laboratory Standards Institute (2013)., Results: Atotal of 460 typhoidal Salmonellaewere isolated; out of which 270 were Salmonella typhiand 190 were Salmonella paratyphiA. The percentage of MDR isolates of S. typhiwas 57% and that of S. paratyphiAwas 42%. None of the isolates were resistant to ceftriaxone, while sensitivity to ciprofloxacin (07% and 0% for S. typhiand S. paratyphiA, respectively) was very low., Conclusion: There is high percentage of MDR isolates of typhoidal Salmonellaein our region. The antimicrobial sensitivity of typhoidal Salmonellaeto conventional agent has not improved enough to recommend their empirical use. There is almost complete resistance to fluoroquinolones as well, leaving very limited available treatment options.

Investigation of the cytotoxic fraction of the extracts of the Red Sea sponge Suberea sp. resulted in the identification of two new compounds, 1-(hydroxy(1H-pyrrol-2-yl)methyl)guanidine and 4-(2-amino-3-methylbut-3-en-1-yl)phenol (1 and 2) together with the previously reported 2-(3,5-dibromo-4-hydroxyphenyl)acetamide (3), subereaphenol C (4), dibromoverongiaquinol (5) and bromochloroverongiaquinol (6). The compounds were assigned by assignment of their one- and two-dimensional NMR and MS spectral data. The cytotoxic activities of the compounds against two cancer cell lines were evaluated. In addition, the antimicrobial activities of the compounds was discussed.

Ginger (Zingiber Officinale) is known over the centuries for its medicinal properties and has been used worldwide as health supplement and for treatment of several diseases. The purpose of this study was to evaluate the effects of whole ginger extract administration on spatial and recognition memory using experimental animal models. The antimicrobial properties of ginger extract against various pathogenic fungal and bacterial species were also examined. Aqueous extract of ginger at a dose of 500 mg/kg was orally administered to test rats and water was orally given to control rats for 6 weeks. Water Maze task (WM) was used to assess spatial memory and recognition memory of rats was evaluated by the Novel Object Recognition (NOR) task. Time spent with novel object was significantly increased in ginger treated rats as compared to control animals in novel object recognition task exhibiting enhanced recognition memory in ginger treated rats. Ginger treated rats exhibited significantly enhanced both short term memory and long term memory as evidenced by decrease in time to reach the hidden platform 1h and 24 h after training as compared to control rats. Short term memory functions of ginger treated rats were more enhanced than long term memory functions. Our findings suggest that ginger consumption may lead to an improvement in spatial and recognition memory. Significant activity of aqueous ginger extract was observed against pathogenic bacteria as well as fungal species. It is therefore suggested in this study that ginger extract can be used in microbial infections and as a memory enhancing drug in various memory disorders.

Antimicrobial activity of pepper polyphenols and capsaicinoids (Coumarin, caffeic acid, narangin, kaempferol, rutin, quercetin, capsaicin, and dihydrocapsaicin) against 13 pathogen bacteria and three beneficial strains was studied using the disk diffusion and microdilution methods. In general, phenolic compounds had the most important activity with the highest inhibition zones obtained with caffeic acid (3.5-20.5 mm), quercetin (4.75-3.5 mm), and kaempferol (7-14 mm). In the determination of the minimal inhibitory concentrations, the effects of both quercetin and kaempferol were more important than caffeic acid. The clinical strains Staphylococcus aureus (319, 14, 8, 32, and 550) were more sensitive to quercetin (0.00195-0.0078 mg L -1 ) whereas kaempferol was more active against the strains S. aureus (ATCC 6538, 26), S. typhimurium ATCC 13311, and Pseudomonas aeruginosa ATCC 27853 (0.0156-0.125 mg L -1 ). The interaction between these three polyphenols was studied against S. aureus ATCC 6538 and P. aeruginosa ATCC 27853. Different modes of interaction were observed (synergism, additive, and indifferent), but no antagonism was obtained. The best combination was quercetin and caffeic acid for S. aureus with fractional inhibitory concentration index (FICI) of 0.37, and kaempferol with quercetin for P. aeruginosa (FICI = 0.31).

Two neutral cyclometalated Ir(iii)-tetrazolato complexes that differ by variations of the substituents on either the phenylpyridine or the tetrazolate ligand have been converted into the corresponding methylated and cationic analogues. NMR ( 1 H and 13 C) characterization of the Ir(iii) complexes provided the results in agreement with the chemo- and regioselective character of methylation at the N-3 position of the Ir(iii)-coordinated tetrazolato ring. This evidence was further corroborated by the analysis of the molecular structures of the cationic complexes obtained by X-ray diffraction. In view of the photophysical properties, the addition of a methyl moiety to neutral Ir(iii) tetrazolates, which behave as sky-blue or orange phosphors, caused a systematic red shift of their phosphorescence output. The transformation of neutral Ir(iii) tetrazolates into cationic Ir(iii)-tetrazole complexes was screened for any eventual antimicrobial activity in vitro against Gram negative (E. coli) and Gram positive (D. radiodurans) microorganisms. While both kinds of complexes were not active against E. coli, the conversion of the neutral Ir(iii) tetrazolates into the corresponding methylated and cationic Ir(iii)tetrazole derivatives determined the turn-on of a good to excellent antimicrobial activity toward Gram positive Deinococcus radiodurans, a non-pathogenic bacterium that is listed as one of the toughest microorganisms in light of its outstanding resistance to radiation and oxidative stress.

In this study, the macrocyclic Schiff base ligand (L) derived from 1, 4-dicarbonyl-phenyl-dihydrazide and glyoxal (2:2) and its Ni (II), Cu (II) and Co(II) complexes were synthesised and were characterised by elemental analyses, FTIR, UV-Vis., mass and 1 H NMR. The ligand (L) behaves as a tetradentate ligand and coordinates to the metal ions via the nitrogen atoms and the complexes have the mononuclear structures. The synthesised compounds were evaluated for their inhibition potential against bacterial and fungal strains and the assay indicated that the metal complexes exhibited a remarkable antibacterial and antifungal activity against these tested strains. In addition, the antioxidant activity of the compounds was also studied through scavenging effect on DPPH radicals with the copper complex showing enhanced antioxidant activity than other metal complexes., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

We report herein, first ever synthesis of series of novel differently substituted quinoxalinyl chalcones using Claisen Schmidt condensation, its molecular docking studies, and potential to be good anti-microbial, anti-tubercular and anti-cancer agents. The antimicrobial studies were carried out against Staphylococcus aureus, Escherichia coli and Candida albicans using disc diffusion procedure. The selected chalcones were tested for anti-cancer and cytotoxicity activity against MCF-7 cancer cell line using MTT assay method. All the synthesized compounds were screened for in vitro anti-tubercular screening against MtbH37RV strains by Alamar blue dye method. These results were compared with molecular docking studies carried out on Mycobacterium tuberculosis enzyme enoyl ACP reductase using Surflex-Dock program that is interfaced with Sybyl-X 2.0. SAR analysis for antimicrobial and antitubercular activity has also been proposed., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Sn 1-x Co x O 2 (x=0.00, 0.01, 0.03, 0.05) nanoparticles (NPs) of average size ∼30-40nm were synthesized by co-precipitation method. The interaction of Co doped SnO 2 NPs with human serum albumin (HSA) and their photocatalytic and antimicrobial properties were studied. The structural analysis and morphology of Co doped SnO 2 NPs were analysed via X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FT-IR). Besides the structural and morphological analysis, the interaction of Co doped SnO 2 NPs with HSA were studied by UV-vis, Circular dichroism (CD) and fluorescence spectroscopy. Fluorescence quenching results suggest that Co doped SnO 2 NPs interact with an HSA molecule through static mechanism. CD indicates that α-helicity of HSA increases due to the interaction of Co doped SnO 2 NPs. The photocatalytic activities of the NPs with increased doping concentration were evaluated through a degradation process in the presence of methylene-blue (MB) dye under UV light irradiation, which exhibited that the surface area of NPs with increased doping concentration plays a major role in improving the photocatalytic activity. The antimicrobial effect of undoped and Co-doped SnO 2 NPs was determined using agar-well diffusion method and analyzed against gram-positive bacteria (Bacillus Cereus MC 2434). In our results, we have found that as the doping concentration increases into NPs, zone of inhibition increases, which could be ascribed to the production of ROS and large surface area of the NPs., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this study, methanol extracts of six medicinal plants (Alstonia macrophylla, Claoxylon indicum, Dillenia andamanica, Jasminum syringifolium, Miliusia andamanica and Pedilanthus tithymaloides) traditionally used by Nicobarese tribes of Andaman and Nicobar Islands were studied for antimicrobial and antimalarial activities as well as preliminary photochemical analysis. Plants were collected from Car Nicobar of Andaman and Nicobar Islands and the ethnobotanical data were gathered from traditional healers who inhabit the study area. The methanol extracts were obtained by cold percolation method and the antimicrobial activity was found using agar well diffusion method. Among the plants tested, J. syringifolium, D. andamanica, C. indicum were most active. The antimalarial activity was evaluated against Plasmodium falciparum chloroquine-sensitive MRC-2 isolate. The crude extract of M. andamanica showed excellent antimalarial activity followed by extracts of P. tithymaloides, J. syringifolium and D. andamanica. The chemical injury to erythrocytes was also carried out and it showed that, there were no morphological changes in erythrocytes by the methanol crude extracts. The in vitro antimicrobial and antimalarial activity might be due to the presence of alkaloids, flavonoids, triterpenes, sterols, tannins and saponins in the methanol extracts of tested plants., (Copyright © 2016 Elsevier Ltd. All rights reserved.)