Multidrug-resistant Microbes Research Articles

Antimicrobial Efficacy of Quercetin against Biofilm Production by <i>Staphylococcus Aureus</i>

Background: The bad administration of antibiotics represents a worldwide health issue as it leads to the emergence of multidrug-resistant microbes including Staphylococcus aureus, which represents a significant challenge for public health since it increases its ability to cause potentially fatal infections. Objective: This study aims to reduce the bacterium’s ability to form biofilms and antibiotic resistance. Methods: Thirty Staphylococcus aureus isolates were isolated from different clinical samples in Baghdad city and their ability to form biofilm was tested using the Microtiter Plate method. Out of 30 isolates, eight strong biofilm producer isolates were further investigated for their antimicrobial activity and biofilm formation with the impact of quercetin. Results: The results showed the ability of quercetin to inhibit bacteria and had an antibiofilm activity that was determined through investigation of the minimal inhibitory concentration by taking different concentrations. The anti-biofilm activity of quercetin was determined for the eight isolates and the results showed that biofilm formation was reduced by 100% using quercetin at a concentration of 3.1 mg/ml. Conclusions: Quercetin represents a suitable alternative to synthetic antimicrobials with the increased rate of drug-resistant bacteria among clinical samples with highly effective ability as anti-biofilm formation among strong biofilm producers of S. aureus.

Revealing detrimental effects of various DC electrical energy conditions on different multidrug resistant bacteria: a comprehensive study

The arbitrary discharge of contaminated wastes, especially that encompass multidrug resistant microbes (MDR), would broaden the circle of epidemic diseases such as COVID-19, which in turn deteriorate definitely the whole socioeconomics. Therefore, the employment of electrical stimulation techniques such as direct current (DC) with low energy considers being effective tool to impede spontaneous changes in microbial genetic makeup, which increases the prevalence of MDR phenomenon. Herein, the influence of different electric energies generated by DC electric field, volts and time on MDR-bacteria that are categorized among the highly ranked nosocomial pathogens, was scrutinized. Wherein, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis were examined as paradigms of Gram-negative and Gram-positive pathogens. The results declared the significant superior antagonizing potency of electric energy in a dose-dependent modality rather than the applied volts or exposure time. Notably, the exposure of bacterial cultures to140 J inhibited the bacterial count by > 78% and the range of 47–73% for Gram-negative and Gram-positive, respectively. While the suppression in their metabolic activity assessed by > 75% and 41–68%, respectively; reflecting the capability of electrical energy to induce viable but non-culturable (VBNC) state. Similarly, the results of total protein, extracellular protein content and lactate dehydrogenase activity emphasized the cell wall deterioration and losing of cell membrane integrity. Additionally, the elevating in ROS upon DC-exposure participated in DNA fragmentation and plasmid decomposability by the range of 33–60%. Further, SEM micrographs depicted drastic morphological deformations after electrical treatment. Strikingly, DC-treatment impaired antibiotic resistance of the examined strains against several antibiotics by > 64.2%. Generally, our comparative detailed study revealed deleterious potentiality of different DC-protocols in defeating microbial pollution, which could be invested as efficient disinfectant alternative in various sectors such as milk sterilization and wastewater purification.

Bioactive metabolites from endophytes of African club moss- Selaginella kraussiana (Kunze) A. Braun exhibit broad-spectrum pharmaceutical utilities

The search for potent natural compounds from plant and microbial sources is increasing logarithmically to combat various types of health issues of which multidrug-resistant microbes and problems related to oxidative stress are the prime ones. Novel secondary metabolites from endophytes have always been potent alternatives to contemporary antimicrobials and antioxidants. The present study shows that two potent endophytic fungal isolates Ascochyta medicaginicola SK16 and Phomopsis sp. SK5 synthesises non-proteinaceous, thermostable secondary metabolites with broad-spectrum antimicrobial, antioxidative, and cytotoxic activity. Bioassay-guided fractionation revealed that the Ethyl acetate (EA) extract of the cell-free culture extract (CFCE) of SK5 and SK16 constitutes ten and eleven secondary metabolites of which 2,4, -di tert butyl phenol, aziridine- 1,2-amino ethyl, actinobolin, bactobolin, azulene, menthyl acetate, phenol, p-[2-(methylamino)ethyl], and imidazole components were significant. SK16 exhibited strong antimicrobial activity against seventeen pathogens including Methicillin-resistant Staphylococcus aureus (MRSA), and C. albicans with a minimum microbicidal concentration of 100- 400 µg mL−1. These metabolites disrupt the microbial cell membranes causing lethal leakage of biomacromolecules- nucleic acid, protein, and potassium ions. Enzymes involved in the EMP pathway, TCA cycle, and gluconeogenesis were also blocked. Both the biofilm formation and transition of Candida cells from the yeast-to-hyphal form were inhibited. SK5 metabolites are potent radical scavengers with an IC50 of 34.25 ± 0.87 – 195.21 ± 5.73 µg mL−1 against DPPH, ABTS, FRAP, and H2O2 free radical generators and significantly increased antioxidant parameters in treated peritoneal macrophage cells of male Wistar rats. Also, SK5 metabolites were cytotoxic against breast (T47D), pancreatic (MIA Paca-2), lung (A549) and colon (HCT-116) cancer cells. The present findings suggest that metabolites from endophytes of African club moss hold potent pharmaceutical utilities.

Pontederia crassipes Biosynthesised Silver Nanoparticles (AgNPs), Characterisation and Activity against Multidrug-Resistant Microbes

Introduction: Pontederia crassipes (water hyacinth) has been singled out as one of the major causes of enormous economic and ecological losses to tropical water systems and habitats. Almost impossible to eradicate, the ominous species is characterized by rapid multiplication, giving rapid and extensive spread that can choke entire rivers and water bodies. However, vast, diverse bioactive secondary metabolites are found in P crassipes which exhibit an expansive assortment of antibacterial properties used in traditional medicine. The rapid emergence of Multi Drug Resistant (MDR) pathogens to common drugs is a pandemic of global proportions. Global health institutions are calling for a coordinated, global action plan to develop new biomaterials to combat the rising threat by MDR strains and improve treatment outcomes and save lives. This study proposes consumption of the water hyacinth lily species through a novel, material biosynthesis approach not only to manage the aquatic infestation but to develop advanced multifunctional, anti-microbial Silver nanoparticles through bio-reduction and capping of Silver salts targeted at MDR microbes. Methodology: After screening for active phytoconstituents of P.crassipes. The Biosynthesis of Novel AgNPs mediated by phenolic, antibacterial lyophilized hydro-ethanolic extracts from P crassipes as both bioreduction and capping agents was investigated. The resultant AgNPs characteristics, toxicological profiles and the antibacterial effects on 10 common microbes including MDR bacterial strains were evaluated. Observations and Results: TEM revealed that cubic and spherical nanometric AgNPs structures were successfully synthesized with particle size range from 10-60nm. With an average zone of inhibition of 29mm and an MIC of 6.25 µg/ml .The nanoparticles were efficacious against selected MDR strains and common infectious bacterial strains tested. In-vivo acute oral toxicity evaluations confirmed the safety of P crassipes. Conclusion: Biogenic P.crassipes mediated AgNPs are feasible, safe and efficacious and have immense potential for optimization into efficient broad spectrum MDR antibacterial agents.b

Remarkable enhancement of cinnamaldehyde antimicrobial activity encapsulated in capped mesoporous nanoparticles: A new “nanokiller” approach in the era of antimicrobial resistance

Combating antimicrobial resistance is one of the biggest health challenges because of the ineffectiveness of standard biocide treatments. This challenge could be approached using natural products, which have demonstrated powerful therapeutics against multidrug-resistant microbes. In the present work, a nanodevice consisting of mesoporous silica nanoparticles loaded with an essential oil component (cinnamaldehyde) and functionalized with the polypeptide ε-poly-l-lysine is developed and used as an antimicrobial agent. In the presence of the corresponding stimuli (i.e., exogenous proteolytic enzymes from bacteria or fungi), the polypeptide is hydrolyzed, and the cinnamaldehyde delivery is enhanced. The nanodevice's release mechanism and efficacy are evaluated in vitro against the pathogenic microorganisms Escherichia coli, Staphylococcus aureus, and Candida albicans. The results demonstrate that the new device increases the delivery of the cinnamaldehyde via a biocontrolled uncapping mechanism triggered by proteolytic enzymes. Moreover, the nanodevice notably improves the antimicrobial efficacy of cinnamaldehyde when compared to the free compound, ca. 52-fold for E. coli, ca. 60-fold for S. aureus, and ca. 7-fold for C. albicans. The enhancement of the antimicrobial activity of the essential oil component is attributed to the decrease of its volatility due to its encapsulation in the porous silica matrix and the increase of its local concentration when released due to the presence of microorganisms.

Clinical Features and Treatment Outcomes of Carbapenem-Resistant Pseudomonas aeruginosa Keratitis

Evaluation of the microbiological diagnostic profile of multidrug-resistant Pseudomonas aeruginosa keratitis and potential management with rose bengal-photodynamic antimicrobial therapy (RB-PDAT) is important. To document the disease progression of carbapenemase-resistant P aeruginosa keratitis after an artificial tear contamination outbreak. This retrospective observation case series included 9 patients 40 years or older who presented at Bascom Palmer Eye Institute and had positive test results for multidrug-resistant P aeruginosa keratitis between January 1, 2022, and October 31, 2023. Evaluation of type III secretion phenotype, carbapenemase-resistance genes blaGES and blaVIM susceptibility to antibiotics, and in vitro and in vivo outcomes of RB-PDAT against multidrug-resistant P aeruginosa keratitis. Among the 9 patients included in the analysis (5 women and 4 men; mean [SD] age, 73.4 [14.0] years), all samples tested positive for exoU and carbapenemase-resistant blaVIM and blaGES genes. Additionally, isolates were resistant to carbapenems as indicated by minimum inhibitory concentration testing. In vitro efficacy of RB-PDAT indicated its potential application for treating recalcitrant cases. These cases highlight the rapid progression and challenging management of multidrug-resistant P aeruginosa. Two patients were treated with RB-PDAT as an adjuvant to antibiotic therapy and had improved visual outcomes. This case series highlights the concerning progression in resistance and virulence of P aeruginosa and emphasizes the need to explore alternative therapies like RB-PDAT that have broad coverage and no known antibiotic resistance. The findings support further investigation into the potential effects of RB-PDAT for other multidrug-resistant microbes.

Green Synthesis of Zinc Oxide Nanoparticles Using Clove Oil Extract (Syzygium aromaticum) and Evaluate their Antibacterial Activity against MRSA

There is a crucial need for the development of effective antimicrobial agents due to the rising incidence of hospital-acquired bacterial infections caused by multidrug-resistant microbes, leading to significant mortality and morbidity worldwide. Therefore, the current study aimed to synthesize zinc oxide nanoparticles (SaZnONPs) using clove extract through an environmentally friendly technique and to investigate their antibacterial activity against MRSA (Staphylococcus aureus). Clove extract acts as both a capping and reducing agent in the formation of ZnO-NPs. The formation of SaZnONPs was confirmed using various analytical techniques. Initially, clove extract was incubated with a zinc nitrate solution, and the subsequent change in color of the solution indicated the reduction of zinc nitrate ions to ZnO nanoparticles. UV-visible spectroscopy revealed a surface plasmon resonance band of SaZnONPs at 329.26 nm. Additionally, SEM imaging indicated that the nanoparticles had an average size of 41 nm and exhibited a spherical shape. The antibacterial activity of SaZnONPs was evaluated against MRSA using agar well diffusion and minimum inhibitory concentration assays. The phytochemicals present in clove extract facilitated the synthesis of stable ZnO-NPs, demonstrating promising antibacterial properties.

Bio-fabrication of silver nanoparticles using Pterocarpus marsupium: A promising antimicrobial agent for head and neck infections

Pterocarpus marsupium (Roxb.) is an important plant for its diverse pharmacological attributes, including anti-microbial and anti-cancerous effects. The multidrug-resistant (MDR) microbes found in head and neck infections can lead to cancer. Recently, the use of nanoparticles has emerged as an alternative to regular drugs to combat the MDR microbes. The current work aimed to synthesize silver nanoparticles (Pm-AgNPs) from the bark extract of P. marsupium and evaluate its antimicrobial potency against head and neck infection microbes, including Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli. Physical characterization of the Pm-AgNPs revealed its spherical shape, an average size of 35.35 nm, and an overall charge of −27.4 mv. The antimicrobial activities of the Pm-AgNPs were compared to the methanolic bark extract of P. marsupium against the selected MDR species. The Pm-AgNPs exhibited better MIC (0.78 µg/ml) and MBC (3.12 µg/ml) values against S. aureus. Toxicity studies of the Pm-AgNPs were performed in Swiss mice models at different doses (300, 600, 1200, and 2000 mg/kg body weight) followed by histopathological, biochemical, and hematological analysis. The results confirmed the non-toxic nature of the Pm-AgNPs, thus supporting their use as a potent anti-microbial agent in head and neck infections.

Radiology Department: A Potential Source of Multidrug-Resistant Microorganisms: A Cross-Sectional Study at Tertiary Hospital, Palestine.

Globally, healthcare facilities face a great challenge in the form of hospital-acquired infections (HAIs). Aside from the morbidity and mortality they cause, these illnesses are also extremely costly. Research on infection transmission in the medical field has been considerable, but not so much in the radiology department. This study aims to identify the presence of multidrug-resistant (MDR) microbes on surfaces that are frequently touched in computed tomography (CT), magnetic resonance imaging (MRI), ultrasound (US), plain X-ray examination rooms, and portable radiography that are susceptible to contamination as well as to investigate the potential dangers of contracting MDR organisms to patients and healthcare providers. Materials and Method. In this study, 160 swab samples were collected from the radiology department during May and June 2022. Samples were obtained from 80 predefined surfaces twice within and outside of CT and MRI examination rooms as well as from US and plain X-ray machines and portable X-ray machines. Samples were taken at 7:00 a.m. using cotton swabs following the regular cleaning procedure. Bacterial colony-forming units (CFUs) per square centimeter were calculated after swabbing a 100 cm2 surface. Nearly all of the surfaces tested had bacterial CFUs. The highest contamination rate was found on keyboards ranging from (1.2-8) CFU/cm2, the sides of patient tables (1.2-20) CFU/cm2, knee coil (2.4-3) CFU/cm2, and patient leg supports (1.2-8) CFU/cm2. A noticeable increase in the contamination was noticed in June compared to May, and this was consistent with the increase in the number of isolated patients in the hospital, the workload in the radiology department, and the number of patients referred to the hospital. In our study, none of the examined sites showed contamination with MDR Gram-negative bacteria such as extended-spectrum beta-lactamases producing Enterobacterales (ESPL) or Carbapenemase-producing Enterobacterales (CPE). On the other hand, methicillin-resistant Staphylococcus (MRS), vancomycin-resistant Staphylococcus (VRS), and vancomycin-resistant Enterococcus (VRE) were detected. All of the radiology department equipment and sites could be a source of bacterial infection including MDR, so the obligatory and committed disinfection protocol must be revised and implemented in the morning and between patients.

Bioactive ZnO Nanoparticles: Biosynthesis, Characterization and Potential Antimicrobial Applications.

In recent years, biosynthesized zinc oxide nanoparticles (ZnONPs) have gained tremendous attention because of their safe and non-toxic nature and distinctive biomedical applications. A diverse range of microbes (bacteria, fungi and yeast) and various parts (leaf, root, fruit, flower, peel, stem, etc.) of plants have been exploited for the facile, rapid, cost-effective and non-toxic synthesis of ZnONPs. Plant extracts, microbial biomass or culture supernatant contain various biomolecules including enzymes, amino acids, proteins, vitamins, alkaloids, flavonoids, etc., which serve as reducing, capping and stabilizing agents during the biosynthesis of ZnONPs. The biosynthesized ZnONPs are generally characterized using UV-VIS spectroscopy, TEM, SEM, EDX, XRD, FTIR, etc. Antibiotic resistance is a serious problem for global public health. Due to mutation, shifting environmental circumstances and excessive drug use, the number of multidrug-resistant pathogenic microbes is continuously rising. To solve this issue, novel, safe and effective antimicrobial agents are needed urgently. Biosynthesized ZnONPs could be novel and effective antimicrobial agents because of their safe and non-toxic nature and powerful antimicrobial characteristics. It is proven that biosynthesized ZnONPs have strong antimicrobial activity against various pathogenic microorganisms including multidrug-resistant bacteria. The possible antimicrobial mechanisms of ZnONPs are the generation of reactive oxygen species, physical interactions, disruption of the cell walls and cell membranes, damage to DNA, enzyme inactivation, protein denaturation, ribosomal destabilization and mitochondrial dysfunction. In this review, the biosynthesis of ZnONPs using microbes and plants and their characterization have been reviewed comprehensively. Also, the antimicrobial applications and mechanisms of biosynthesized ZnONPs against various pathogenic microorganisms have been highlighted.

Control of Biofilm and Virulence in Pseudomonas aeruginosa by Green-Synthesized Titanium–Cerium Nanocomposites

Antimicrobial resistance (AMR) has become a critical global health challenge. Infections, particularly those caused by multidrug-resistant (MDR) pathogens, rank among the top causes of human mortality worldwide. Pseudomonas aeruginosa occupies a prominent position among pathogens responsible for opportunistic infections in humans. P. aeruginosa stands as a primary cause of chronic respiratory infections, significantly contributing to the burden of these chronic diseases. In the medical domain, nanotechnologies offer significant potential, spanning various applications, including advanced imaging, diagnostic devices, drug delivery systems, implants, tissue-engineered structures, and pharmaceutical treatments. Given the challenges associated with AMR and the limited discovery of new drugs to combat MDR microbes, there is a critical need for alternative strategies to address the problem of AMR. In this study, we synthesized titanium–cerium nanocomposites (Ti–Ce–NCs) using an eco-friendly green synthesis approach. X-ray diffraction (XRD) analysis confirmed the crystalline nature of the Ti–Ce–NCs and determined the particle size to be 17.07 nm. Electron microscopy revealed the size range of the particles to be 13 to 54 nm, where the majority of the particles were in the 20 to 25 nm range. Upon examining the composition, the Ti–Ce–NCs were determined to be composed of cerium, oxygen, and titanium, whose relative abundance were 36.86, 36.6, and 24.77% by weight, respectively. These nanocomposites were then evaluated for their effectiveness against various virulent traits and biofilms in P. aeruginosa. Out of six tested virulence factors, more than 50% inhibition of five virulence factors of P. aeruginosa was found. Roughly 60% inhibition of biofilm was also found in the presence of 400 µg/mL Ti–Ce–NCs. The nanocomposites also altered the biofilm architecture of the test bacterium. The success of this research opens doors for the potential use of such nanomaterials in the discovery of new antibacterial agents to combat drug-resistant bacteria.

Emergence of Multidrug Resistant Microbial Species in the Bacterial Profile of Burn Wounds: A Cohort Study from Pak Italian Modern Burn Center, Multan

Objective: To document the prevalence of microflora causing burn wound infections in our setup, track any trends of change in the flora after a 7-day treatment period, and document any rise in the incidence of multidrug-resistant microbes. Methods: This cohort study was conducted at the Pak Italian Modern Burn Centre (PIBC), Multan, over a one-year period from January 2022 to December 2022. Surface wound swabs were collected from 150 patients admitted to the Burn unit on day 3, day 10, and day 17 after sustaining burns. Standard procedures for isolation and identification of microorganisms were followed, and the growth of microflora obtained was subjected to antibiotic sensitivity testing following the Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: Gram-negative isolates included Pseudomonas aeruginosa, Escherichia coli, Klebsiella spp., Citrobacter spp., Proteus vulgaris, and Providencia mirabilis. Gram-positive isolates included Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA). Pseudomonas aeruginosa caused 39.3% of wound infections within 72 hours of admission and 56.9% of wound infections by the first week post-burn. Proteus vulgaris (36%) was the most frequently isolated microorganism in the second week post-burn. All these isolates exhibited an alarming level of resistance to routinely used antibiotics, necessitating the use of older, less safe antibiotics like colistin for gram-negative infections. Conclusions: The rising incidence of antimicrobial resistance can be attributed to the emergence of multidrug-resistant bacterial species found in burn patients. Overcrowding in burn treatment facilities further exacerbates the risk of cross-contamination.

Valorisation of the Invasive Macroalgae Undaria pinnatifida (Harvey) Suringar for the Green Synthesis of Gold and Silver Nanoparticles with Antimicrobial and Antioxidant Potential.

Bacterial and fungal infections are a challenging global problem due to the reported increasing resistance of pathogenic microorganisms to conventional antimicrobials. Nanomaterials are a promising strategy to fight infections caused by multidrug-resistant microbes. In this work, gold (Au@UP) and silver (Ag@UP) nanoparticles were produced for the first time by green synthesis using an aqueous extract of the invasive macroalgae Undaria pinnatifida (UP). The nanoparticles were characterized by a wide range of physicochemical techniques. Au@UP and Ag@UP demonstrated to be spherical and crystalline with an average size of 6.8 ± 1.0 nm and 14.1 ± 2.8 nm, respectively. Carbohydrates and proteins of the UP extract may participate in the synthesis and capping of the nanoparticles. The UP extract, Ag@UP, and Au@UP were assessed for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Ag@UP showed the highest antimicrobial activity with very low MIC and MBC values for all the tested bacteria, and Au@UP demonstrated to be very effective against biofilm-producing bacteria. The antifungal properties of both Ag@UP and Au@UP were remarkable, inhibiting hyphae formation. This study points towards a very promising biomedical exploitation of this invasive brown algae.

Enhanced therapeutic efficacy of biogenic nanosilver-conjugated thymol: In vitro and in vivo evaluation against emerging multi-drug resistant microbes

Phytochemicals and nanoparticles (NPs) despite having strong antibacterial activity, their limited stability and safety prevent their widespread biomedical and environmental applications. Therefore, the bio-efficacy and environmental safety of both can be increased by fabricating and conjugating them using eco-friendly processes. Herein, the impact of a novel green nanomedicine, nanosilver-conjugated thymol (AgT), was evaluated against multi-drug resistant enteroaggregative Escherichia coli (MDR-EAEC) strains using in vitro and in vivo (Galleria mellonella) assays. Characterization of AgT by UV–Vis and FTIR spectroscopy demonstrated the conjugation of thymol with biogenic nanosilver with a loading capacity of 16.60 ± 0.24%. Electron microscopy revealed mono-dispersed spherical morphology with a size of 15.077 ± 3.34 nm. The minimum inhibitory concentration (4–16 μg/mL) and minimum bactericidal concentration (8–16 μg/mL) were five to six-fold times lower than thymol. The antibacterial efficacy of AgT was at par with meropenem in the in vitro time-kill assay. Moreover, AgT was tested safe against gut lactobacilli, sheep erythrocytes, RAW 264.7 and HEp-2 cell lines; stable at various high-end temperatures, pH, proteases, cationic salts, and host sera. G. mellonella larvae treated with AgT exhibited higher survival rates and safety with reduced MDR-EAEC counts. Overall, compared to thymol, AgT showed promising therapeutic potential with improved safety.

Multi-drug resistant microbes are resident on nose masks used as preventive protocols for COVID-19 in selected Ghanaian cohort

Background: Use of nose masks was an effective and significant part of the World Health Organization (WHO) coronavirus disease (COVID-19) preventive protocols; however, unhygienic practices by the user could lead to microbial contamination of masks. This study profiled bacteria and fungi resident on nose masks and established unhygienic practices; which was not prioritized during the COVID-19 pandemic. Methods: This was a cross-sectional exploratory study, and questionnaires on unhygienic practices toward mask use were completed by 100 consenting participants from which their nose masks were collected for microbial assessment. The isolated microorganisms were characterized with phenotypic and molecular assays. Data were analyzed with descriptive statistics and presented in graphs. Results: Overall, 65% out of the 100 participants reported using a single nose mask for more than a day and 31% washed the mask to reuse. The bacterial load on the exterior (9.9 x 104 CFU/ml) mask interior (9.1 x 104 CFU/ml) was higher than the threshold outlined by WHO. Streptococcus, Staphylococcus, Bacillus, Proteus, Citrobacter, Salmonella, Penicillium, and Aspergillus species were isolated from the mask, and about 80-100% of these isolates were resistant to 18 antimicrobials tested. Uncommon bacterial and fungal isolates, including Providencia, Morganella, Edwardsiella, Rhodotorula and Fusarium species, were also resident on the masks. Conclusions: Diverse multidrug-resistant pathobionts resided on the used mask. These microbes can be opportunistic and cause infections. Nose masks have become a common social accessory; thus strategies are required to ease user discomfort and encourage hygiene practices.

Molecular typing of multidrug resistant bacteria isolated from health care professionals’ mobile phone: A pilot study in Jashore, Bangladesh

Background: Nowadays, Health Care Professionals’ (HCPs) are increasingly using mobile phones which may act as reservoirs and vector for transmission of pathogens. The presence of multidrug resistant nosocomial microbes on the surface of mobile phones used by HCPs in hospitals can pose a great public health threat. So, this research was conducted to identify the concerned multi-drug resistant (MDR) bacteria and also to explore the recent status of bacterial contamination on mobile phones of HCPs in the Jashore region of Bangladesh and determine their antibiotic resistance pattern. Methods: Swab samples of mobile phones were collected between June and September 2019 from 24 different users (i.e., manager, worker, doctor and nurse) associated to four distinct hospitals of Jashore region, Bangladesh. After suitable morphological and biochemical identification, we determined their antimicrobial susceptibility by Kirby- Bauer disc diffusion method by using 18 antibiotics for Gram positive bacteria and 19 antibiotics for Gram negative bacteria. Later, the MDR isolates were grouped by amplified ribosomal DNA restriction analysis (ARDRA) and 16S rRNA sequencing with phylogeny were performed to confirm the bacteria at species level. Results: A total of 38 bacterial isolates were obtained from the sample. Enterobacter spp. isolates showed maximum resistance against Amoxicillin, followed by Ampicillin and Aztreonam (80% each) and one isolate showed highest antibiotic resistance (15 out of 19) among all the isolates. In addition, Staphylococcus spp. and Exiguobacterium spp. isolates showed 100% resistance against Penicillin, Ampicillin, Oxacillin, Erythromycin, Lincomycin and Cefotaxime. On the contrary, all of the isolates of Escherichia spp., Bacillus spp., Proteus spp. were sensitive to all tested antibiotics. Surprisingly, 20 MDR isolates were showing resistance to at least 2 antibiotics. Subsequently, three distinct genera of these MDR isolates were identified by ARDRA; the strains Enterobacter cloacae (75%), Staphylococcus warneri (15%) and Exiguobacterium aurantiacum (10%) were confirmed by the 16S rRNA phylogenetic analysis. Conclusion: We found that cell phones can act as reservoirs of multidrug-resistant pathogens, causative agents for Hospital-acquired infections. An effective hygiene practice for health care personnel should be introduced to prevent the cross-contamination by their cell phone Bangladesh Journal of Medical Science Vol. 22 No. 03 July’23 Page : 643-656

Antimicrobial-Resistant Infections after Turkey/Syria Earthquakes, 2023.

Increased rates of multidrug-resistant microbes have been reported after earthquakes. After the 2023 earthquakes in Turkey and Syria, the number of associated highly drug-resistant pathogens and nosocomial transmission will probably surge in hospitals treating injured patients. It is not too late to act to prevent antimicrobial-resistant infections from compounding these tragedies.

Evaluation of Biomedical Applications for Linseed Extract: Antimicrobial, Antioxidant, Anti-Diabetic, and Anti-Inflammatory Activities In Vitro.

In the last few decades, the development of multidrug-resistant (MDR) microbes has accelerated alarmingly and resulted in significant health issues. Morbidity and mortality have increased along with the prevalence of infections caused by MDR bacteria, making the need to solve these problems an urgent and unmet challenge. Therefore, the current investigation aimed to evaluate the activity of linseed extract against Methicillin-resistant Staphylococcus aureus (MRSA) as an isolate from diabetic foot infection. In addition, antioxidant and anti-inflammatory biological activities of linseed extract were evaluated. HPLC analysis indicated the presence of 1932.20 µg/mL, 284.31 µg/mL, 155.10 µg/mL, and 120.86 µg/mL of chlorogenic acid, methyl gallate, gallic acid, and ellagic acid, respectively, in the linseed extract. Rutin, caffeic acid, coumaric acid, and vanillin were also detected in the extract of linseed. Linseed extract inhibited MRSA (35.67 mm inhibition zone) compared to the inhibition zone (29.33 mm) caused by ciprofloxacin. Standards of chlorogenic acid, ellagic acid, methyl gallate, rutin, gallic acid, caffeic acid, catechin, and coumaric acid compounds reflected different inhibition zones against MRSA when tested individually, but less than the inhibitory action of crude extract. A lower MIC value, of 15.41 µg/mL, was observed using linseed extract than the MIC 31.17 µg/mL of the ciprofloxacin. The MBC/MIC index indicated the bactericidal properties of linseed extract. The inhibition % of MRSA biofilm was 83.98, 90.80, and 95.58%, using 25%, 50%, and 75%, respectively, of the MBC of linseed extract. A promising antioxidant activity of linseed extract was recorded, with an IC50 value of 20.8 µg/mL. Anti-diabetic activity of linseed extract, expressed by glucosidase inhibition, showed an IC50 of 177.75 µg/mL. Anti-hemolysis activity of linseed extract was documented at 90.1, 91.5, and 93.7% at 600, 800, and 1000 µg/mL, respectively. Anti-hemolysis activity of the chemical drug indomethacin, on the other hand, was measured at 94.6, 96.2, and 98.6% at 600, 800, and 1000 µg/mL, respectively. The interaction of the main detected compound in linseed extract (chlorogenic acid) with the crystal structure of the 4G6D protein of S. aureus was investigated via the molecular docking (MD) mode to determine the greatest binding approach that interacted most energetically with the binding locations. MD showed that chlorogenic acid was an appropriate inhibitor for S. aureus via inhibition of its 4HI0 protein. The MD interaction resulted in a low energy score (-6.26841 Kcal/mol) with specified residues (PRO 38, LEU 3, LYS 195, and LYS 2), indicating its essential role in the repression of S. aureus growth. Altogether, these findings clearly revealed the great potential of the in vitro biological activity of linseed extract as a safe source for combatting multidrug-resistant S. aureus. In addition, linseed extract provides health-promoting antioxidant, anti-diabetic, and anti-inflammatory phytoconstituents. Clinical reports are required to authenticate the role of linseed extract in the treatment of a variety of ailments and prevent the development of complications associated with diabetes mellitus, particularly type 2.

Mechanistic insights into antibacterial and anti-biofilm activities against multidrug-resistant microbes of SnTe nanospheres synthesized by sonochemical method

The sonochemical method is used to synthesize SnTe nanoparticles (Nps). Elemental analyses validated the stoichiometry of the nanoparticles. The phase and structure of the unit cell are verified by X-ray diffraction which shows nanoparticles are SnTe phase and a cubic crystal structure with a unit-cell lattice parameter of 6.31 Å having Fm-3m space group (No. 225), with Z = 4. The spherical form of nanoparticles is confirmed by electron microscopy. The Raman investigation showed a distinctive peak at 128.10 cm−1 connected to SnTe. The HR-TEM scans demonstrate that the Nps has size ranging between 25 and 30 nm and SnTe phase is confirmed by match of fringe pattern d-spacing. The SnTe Nps showed antibacterial properties through the formation of biofilms. The as-synthesized nanoparticles showed an efficient anti-microbial effect on staphylococcus aureus (MTCC 9542), listeria monocytogenes (MTCC 657), and proteus vulgaris (MTCC 426) bacteria. The study showed 100% growth suppression after 24 h of treatment with SnTe Nps, demonstrating the antimicrobial efficacy of SnTe Nps. The MIC (IC50) of 20 μg/mL for staphylococcus aureus is found to be resistant to the SnTe Nps effective anti-biofilm action. Based on these results, the authors looked into the feasibility of coating surfaces with the sample to prevent the growth of biofilms.

Chemical Composition, Antibacterial and Combinatorial Effects of the Essential Oils from Cymbopogon spp. and Mentha arvensis with Conventional Antibiotics

This work aimed to evaluate the chemical composition and antibacterial activity of essential oils of Cymbopogon citratus (CCEO), Cymbopogon khasianus (CKEO), and Mentha arvensis (MAEO) against two Gram-negative (Escherichia coli, Klebsiella pneumoniae) and three Gram-positive (Staphylococcus aureus, Micrococcus luteus, Bacillus subtilis) microbial strains and their combination with antibiotics (chloramphenicol, ampicillin, erythromycin) to observe the synergistic behavior between them. The essential oils (EOs) were investigated by the GC-MS (gas chromatography mass spectrometry) method. The synergistic effect between EOs and antimicrobial agents was analyzed by broth dilution assay. (-)-carvone (52.48%), geraniol (57.66%), and citral (37.83%) were the major components identified in EOs of MAEO, CKEO, and CCEO, respectively. According to the antibacterial activity, EOs demonstrated strong antibacterial activity with MIC values ranging from 0.7 to 18 mg/mL. The interaction between the combination of EOs and antibiotics was determined in terms of FICI (Fractional Inhibitory Concentration Index). Some combinations displayed a partial synergistic effect, and some showed a synergistic and others displayed no effect against bacterial strains. The best synergistic action was shown by the combination of CCEO and Chloramphenicol against E. coli with a FICI value of 0.4. Three to four fold reductions in the MIC value of both essential oil and antibiotics were observed. Therefore, this synergistic interaction of the most active EOs with synthetic antibiotics could lead to new combination therapies for combating infections caused by multidrug-resistant microbes at sufficiently low concentrations in the pharmaceutical and food industry.