The emergence of resistant pathogens is a burden on mankind and threatens the existence of our species. Natural and plant-derived antimicrobial agents need to be developed in the race against antibiotic resistance. Nanotechnology is a promising approach with a variety of products. Biosynthesized silver nanoparticles (AgNP) have good antimicrobial activity. We prepared AgNPs with trans-cinnamic acid (TCA) and povidone-iodine (PI) with increased antimicrobial activity. We synthesized also AgNPs with natural cinnamon bark extract (Cinn) in combination with PI and coated biodegradable Polyglycolic Acid (PGA) sutures with the new materials separately. These compounds (TCA-AgNP, TCA-AgNP-PI, Cinn-AgNP, and Cinn-AgNP-PI) and their dip-coated PGA sutures were tested against 10 reference strains of microorganisms and five antibiotics by zone inhibition with disc-and agar-well-diffusion methods. The new compounds TCA-AgNP-PI and Cinn-AgNP-PI are broad spectrum microbicidal agents and therefore potential coating materials for sutures to prevent Surgical Site Infections (SSI). TCA-AgNP-PI inhibits the studied pathogens stronger than Cinn-AgNP-PI in-vitro and on coated sutures. Dynamic light scattering (DLS), ultraviolet-visible spectroscopy (UV-Vis), Fourier Transform infrared spectroscopy (FT-IR), Raman, X-ray diffraction (XRD), microstructural analysis by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) confirmed the composition of TCA-AgNP-PI and Cinn-AgNP-PI. Smart solutions involving hybrid materials based on synergistic antimicrobial action have promising future perspectives to combat resistant microorganisms.Pharmaceutics 2020, 12, 361 2 of 36 20,000 related deaths in the United States in 2017 only and remains to be one of the important infection-associated mortality reasons [11,12]. The formation of biofilms on biotic and abiotic surfaces [13] paved the way for biofilm antibiotic tolerance as another major health threat [14,15]. This additional problem hampers the treatment of infections, most often gives rise to chronic infections, in the worst case to therapeutic failure, severe morbidity, and mortality [4]. More than 80% of microbial infections are caused by microbial biofilm formation and pose a severe health risk because treatment with antibiotics remains ineffective [16]. The incidence of chronic wound infections is increasing globally to alarming levels [17]. Chronic wounds are marked by high bacterial colonization and infection rates, which can be treated only by novel therapeutic approaches other than the use of conventional antibiotics [18,19]. Chronic wound tissues can contain microbiomes of complex communities with coexisting fungal and bacterial colonies of different strains within biofilms [20]. According to this inter-kingdom model, fungi like Candida albicans can offer structures for other bacteria (S. aureus, P. aeruginosa, Streptococcus spp., E. faecalis, E. coli, and Acinetobacter baumannii etc.) to attach, form intricate biofilms, and increase the resistance against any ...

Antimicrobial agents containing symmetrical triiodides complexes with halogen bonding may release free iodine molecules in a controlled manner. This happens due to interactions with the plasma membrane of microorganisms which lead to changes in the structure of the triiodide anion. To verify this hypothesis, the triiodide complex [Na(12-crown-4)2]I3 was prepared by an optimized one-pot synthesis and tested against 18 clinical isolates, 10 reference strains of pathogens and five antibiotics. The antimicrobial activities of this symmetrical triiodide complex were determined by zone of inhibition plate studies through disc- and agar-well-diffusion methods. The triiodide complex proved to be a broad spectrum microbicidal agent. The biological activities were related to the calculated partition coefficient (octanol/water). The microstructural analysis of SEM and EDS undermined the purity of the triiodide complex. The anionic structure consists of isolated, symmetrical triiodide anions [I-I-I]- with halogen bonding. Computational methods were used to calculate the energy required to release iodine from [I-I-I]- and [I-I···I]-. The halogen bonding in the triiodide ion reduces the antibacterial activities in comparison to the inhibitory actions of pure iodine but increases the long term stability of [Na(12-crown-4)2]I3.

Antimicrobial resistance (AMR) is a challenge for the survival of the human race. The steady rise of resistant microorganisms against the common antimicrobials results in increased morbidity and mortality rates. Iodine and a plethora of plant secondary metabolites inhibit microbial proliferation. Antiseptic iodophors and many phytochemicals are unaffected by AMR. Surgical site and wound infections can be prevented or treated by utilizing such compounds on sutures and bandages. Coating surgical face masks with these antimicrobials can reduce microbial infections and attenuate their burden on the environment by re-use. The facile combination of Aloe Vera Barbadensis Miller (AV), Trans-cinnamic acid (TCA) and Iodine (I2) encapsulated in a polyvinylpyrrolidone (PVP) matrix seems a promising alternative to common antimicrobials. The AV-PVP-TCA-I2 formulation was impregnated into sterile discs, medical gauze bandages, surgical sutures and face masks. Morphology, purity and composition were confirmed by several analytical methods. Antimicrobial activity of AV-PVP-TCA-I2 was investigated by disc diffusion methods against ten microbial strains in comparison to gentamycin and nystatin. AV-PVP-TCA-I2 showed excellent antifungal and strong to intermediate antibacterial activities against most of the selected pathogens, especially in bandages and face masks. The title compound has potential use for prevention or treatment of surgical site and wound infections. Coating disposable face masks with AV-PVP-TCA-I2 may be a sustainable solution for their re-use and waste management.

Nano-sized metals have been introduced as a promising solution for microbial resistance to antimicrobial agents. Silver nanoparticles (AgNPs) have been proven to possess good antimicrobial activity. Green synthesis of AgNPs has been reported as safe, low cost and ecofriendly. This methodology uses extracts originating from different plants to reduce silver ions from AgNO 3 into nano-sized particles. In this study, extracts of several plants including ginger, garlic, capsicum and their mixtures were successfully used to produce AgNPs. Numerous spectroscopic, light scattering and microscopic techniques were employed to characterize the synthesized AgNPs. Agar well diffusion assay was performed to investigate the antimicrobial activity of AgNPs. The biosynthesized AgNPs have spherical shape with a size range of 20-70 nm. Garlic extract, pure or in mixture with ginger extract, generated AgNPs of the smallest size. The presence of the plant-origin capping agents surrounding AgNPs was proven by Fourier-transform infrared spectroscopy. The AgNPs, at a concentration of 50 µg/mL, demonstrated potent antimicrobial activity against Staphyloccocus aureus, Escherichia coli and Candida albicans as indicated by the zones of inhibitions. Our results revealed that AgNPs having potent antimicrobial activity could be prepared using different pure plant extracts and their mixtures.

The coronavirus disease 2019 (COVID-19) claimed until now more than 730.000 lives globally. Prevention and infection control measures were implemented in many countries, including the United Arab Emirates (UAE). Frontline healthcare workers in health care settings and pharmacists are susceptible to be infected by the virus. During a pandemic, the knowledge, attitude and practice of these two groups play a major role in saving lives and reducing infection rate. The aim of this study was to assess COVID-19 related knowledge, self-reported preventive behaviors and risk perception. This cross-sectional study was conducted during the first two weeks of April, 2020. We assessed pharmacy students' knowledge, preventive behaviors and risk perceptions of COVID-19 using an online questionnaire. Questions were based on the Centers of Disease Control (CDC) guidelines and the reliability of the questionnaire was shown to be satisfactory. The study revealed a good level of knowledge about the pandemic and its control. A positive relationship was observed between the knowledge and attitude of participants. We found a high level of COVID-19 related knowledge and selfreported preventive behaviors among pharmacy students in the UAE especially in students of senior levels. This study helps the authorities to develop strategies in future pandemics regarding healthcare system shortages.

New antibacterial agents are needed to overcome the increasing number of infectious diseases caused by pathogenic microorganisms due to the emergence of multi-drug resistant strains. In this context, halogens, especially Iodine is known since ages for its antimicrobial activity. Therefore, especially triiodides encapsulated in organometallic complexes can be helpful as new agents against microorganisms. The aims of this work was to study the biological activity of [Na(12-Crown-4)2]I3 against gram positive Streptococcus pyogenes, Streptococcus faecalis, the spore forming bacteria Bacillus subtilis and gram negative bacteria Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Klebsiella pneumoniae, as well as the yeast Candida albicans. The antimicrobial and antifungal activities of the triiodide were determined by zone of inhibition plate studies. [Na(12-Crown-4)2]I3 exhibited potent antimicrobial activity on gram positive Streptochocci and the yeast C. albicans. Furthermore, the gram negative bacteria P. aeruginosa and K. pneumoniae were less effectively inhibited, while E. coli and P. mirabilis proved to be even resistant.

Antimicrobial and antibiotic resistance is a major threat to mankind due to increasing resistance towards existing medicinal drugs. Plant-based antimicrobials are promising alternatives to conventional drugs. Cress (Lepidium sativum L.) is known as garden cress, garden cress pepper weed or garden pepperwort and is a member of the Brassicaceae family. Lepidium satvium L. (LS) is widely spread throughout the world as a fast-growing annual herb. LS seed oil has antimicrobial, antioxidant, and anti-inflammatory activities. Silver nanoparticles (AgNP) gained attention due to their antimicrobial properties. We aimed to synthesize LS encapsulated AgNP to enhance the microbicidal activities of the nanoparticles and prevent microbial resistance by plant-based synergistic mechanisms. AgNP were prepared in a one-pot synthesis by plant-biomolecules-induced reduction of silver nitrate via green method. The biomolecules and metabolites in the aqueous LS extract act as reducing, capping and stabilizing agents of AgNP. Fourier transform infrared spectroscopy (FT-IR), Ultravioletvisible spectroscopy (UV-Vis) and Dynamic light scattering (DLS) confirmed the composition of the LS-AgNP biohybrids. Antimicrobial testing by disc dilution method against a total of 9 reference strains of microorganisms verified excellent to intermediate antimicrobial activity. The Gram-negative pathogens E. coli WDCM 00013 and P. aeruginosa WDCM 00026 were highly inhibited, followed by good results for the Gram-positive bacteria S. aureus ATCC 25923, B. subtilis WDCM 00003, S. pyogenes ATCC 19615, E. faecalis ATCC 29212, and the fungus C. albicans WDCM 00054. Our biohybrid LS-AgNP showed increased antimicrobial activity with potential uses as disinfectant and wound care product.

Multi-drug resistant ESKAPE pathogens are listed by WHO as threat to mankind. These microorganisms developed resistance mechanisms against some commonly used antimicrobials and drugs. New antimicrobials can be a combination of nanotechnology and plant constituents. Silver nanoparticles demonstrated already in many investigations unique antimicrobial properties during the last decade. Plants contain multiple biocompounds, which exert antimicrobial activities due to their synergistic actions. We investigated the antimicrobial activities of well-known cinnamomum zeylanicum (Cinn) with iodine (I 2 ), stabilized with polyvinypyrrolidone and compared the results with their trans-cinnamic acid (TCA) equivalents. The compounds were tested against five microbial strains by agar-well and disc-diffusion methods on discs and polyglycolic acid (PGA) sutures. The title compounds were characterized by different analytical methods and showed excellent to intermediate inhibition of the tested pathogenic strains. Our compounds can be seen as alternative disinfectants and coating agents on surgical sutures in the prevention of surgical site infections.