Multiple Drug Resistant Microorganisms Research Articles

Antibacterial Activities of Cassia angustifolia Leaf Ethanolic Extract against Various Multiple Drug Resistant Microorganisms

Cassia angustifolia is a plant best known for its medicinal properties, commonly known as Indian Senna. This is a flowering plant belonging to the Fabaceae family. In this Study, the antibacterial activities of ethanolic extract of Cassia angustifolia leaves were evaluated against MDR Microorganisms. The antimicrobial activity of the extract was assessed against a range of bacterial strains, including Escherichia coli (MDR), Klebsiella sp. (MDR), Pseudomonas sp. (MDR), and Acinetobacter sp. (MDR). The result showed that the leaf extract of Cassia angustifolia exhibit significant antimicrobial activity against all tested MDR Microorganisms. The phytochemical content of the plant includes many bioactive compounds like Tannins, Saponins, Flavonoids, Alkaloids, Steroids and quinones etc which may be responsible for the observed antimicrobial activities. These findings suggest that Indian Senna, which could be used to develop new drugs for the treatment of resistant bacterial infections.

Antibacterial Activities of Cassia angustifolia Leaf Ethanolic Extract against Various Multiple Drug Resistant Microorganisms

Cassia angustifolia (Indian Senna), a plant from the Fabaceae family, is an important medicinal plant of India and it is drought tolerant, hence it is cultivated under rain fed condition in marginal soils by small and marginal farmers of Gujarat, Rajasthan, Maharashtra, Andhra Pradesh and other Indian states. In this study, the antibacterial activities of ethanolic extract of Cassia angustifolia leaves were assessed against ATCC microorganisms - gram negative bacteria Escherichia coli (ATCC 25922) and gram positive bacteria Staphylococcus aureus(ATCC 25923). The result showed that C. angustifolia leaf extracts exhibited significant antimicrobial activity against both tested ATCC microorganisms. In this plant, Resin, Phenol, Coumarins, Alkaloids, Saponin, Steroid, etc, the phytochemical contents and the laxative principle Sennoside A and Sennoside B (two crystaline glucosides), which may be responsible for the observed antimicrobial activities. From these findings, we suggest that C. angustifolia (Indian senna) may be a possible source of natural antimicrobial agents, which could be used to develop new drugs for the treatment of resistant bacterial infections. Further studies on C. angustifolia on a large scale may open a new scope for other researchers to carry it.

Antibacterial and Antifungal Activities of Avicennia marina Extract Against Various Multiple Drug Resistant Microorganisms

Avicennia marina is a commonly found mangrove species in coastal regions, and is known for its medicinal properties. In this study, the antibacterial and antifungal activities of ethanolic extract of Avicennia marina leaves were evaluated against MDR microorganisms. The antimicrobial activity of the extract was assessed against a range of bacterial strains, including Salmonella sp. (MDR), Klebsiella sp. (MDR), Pseudomonas sp. (MDR), Acinetobacter sp. (MDR), Staphylococcus aureus as well as the fungal strain Candida albicans (ATCC 10231), Candida parapsilosis (ATCC 22019). The results showed that the leaf extracts of Avicennia marina exhibited significant antimicrobial activity against all tested MDR microorganisms. The phytochemical content of the plant includes many bioactive compounds - flavonoids, tannins, and alkaloids, which may be responsible for the observed antimicrobial activities. These findings suggest that Avicennia marina may be a potential source of natural antimicrobial agents, which could be used to develop new drugs for the treatment of resistant bacterial and fungal infections. Further studies are needed to identify and isolate the active compounds responsible for the observed activity and to evaluate their efficacy and safety in vivo.

Effect of antimicrobial peptide conjugated surgical sutures on multiple drug-resistant microorganisms.

Surgical site infections are commonly encountered as a risk factor in clinics that increase the morbidity of a patient after a surgical operation. Surgical sutures are one of the leading factor for the formation of surgical site infections that induce bacterial colonization by their broad surface area. Current strategies to overcome with surgical site infections consist utilization of antibiotic agent coatings such as triclosan. However, the significant increase in antibiotic resistance majorly decreases their efficiency against recalcitrant pathogens such as; Pseudomonas aeruginosa and Staphylococcus aureus. Therefore, the development of a multi drug-resistant antimicrobial suture without any cytotoxic effect to combat surgical site infections is vital. Antimicrobial peptides are the first defense line which has a broad range of spectrum against Gram-positive, and Gram-negative bacteria and even viruses. In addition, antimicrobial peptides have a rapid killing mechanism which is enhanced by membrane disruption and inhibition of functional proteins in pathogens without the development of antimicrobial resistance. In the scope of the current study, the antimicrobial effect of antimicrobial peptide conjugated poly (glycolic acid-co-caprolactone) (PGCL) sutures were investigated against P. aeruginosa and methicillin-resistant S. aureus (MRSA) strains by using antimicrobial peptide sequences of KRFRIRVRV-NH2, RWRWRWRW-NH2 and their dual combination (1:1). In addition, in vitro wound scratch assays were performed to evaluate the effect of antimicrobial peptide conjugated sutures on keratinocyte cell lines. Our results indicated that antimicrobial peptide modified sutures could be a potential novel medical device to overcome surgical site infections by the superior acceleration of wound healing.

The Prevalence of Gram-Negative Microorganisms Isolated from Ventilator-Associated Pneumonia Patients in the Intensive Care Units of Southwest of Iran

Background: Increasing microbial resistance is a severe threat to global public health. One of the most common diseases in the intensive care unit is ventilator-associated pneumonia.
 Methods: The method of this research was non-interactive and descriptive. This study was carried out from January to March 2018, at the Golestan Hospital of Ahvaz. Patients with ventilator-associated pneumonia (VAP) were included in the study. The prevalence of resistant gram-negative microorganisms was studied through reported laboratory antibiogram results of cultures.
 Results: From 373 hospitalized patients, 38 (10.2%) were diagnosed with VAP. From the 57 respiratory cultures performed, overall 90 microorganisms were isolated, from which Enterobacter with 36 cases (39.5%) and E.Coli with 28 cases (30.7%) were most frequently compared to other organisms. From the 90 organisms responsible for the infection, 43 cases (47.2%) were Multiple drug-resistant (MDR) microorganisms and 47 (51.6%) were Extensively drug-resistant (XDR) microorganisms. Enterobacter and E.Coli were the most prevalent MDR microorganisms with 17 cases (39.5%) and 13 (30.2%), respectively. Also, these two microorganisms were the most abundant XDR microorganisms with 19 cases (40.4%) and 15 (31.9%), respectively.
 Conclusion:The results show the requirement of robust antibiotic monitoring and the optimization of antibiotic use in order to prevent the progression of antibiotic resistance in these units.

PHYTOCHEMICAL SCREENING AND ANTIMICROBIAL EFFECT OF SEEDS OF Monodora myristica ON SELECTED MICROORGANISMS

The increase in the prevalence of effects of many synthetic antimicrobial agents and incidence of multiple drug resistant microorganisms has spurred scientists on the research for plant-based antimicrobial of therapeutic potentials. The Monodora myristica has been used in Nigeria traditionally as condiments and has been harnessed as a therapeutic agent in the treatment of skin infection and dysentery. Aqueous, n-hexane and ethanolic extracts of the seeds was screened for antimicrobial activity against pathogenic microorganisms implicated in causing vagina infections. This finding showed that the efficacy of the extracts was concentration dependent. Aqueous, ethanolic and N-hexane extract showed varying degree of inhibition with different magnitude against the test isolates. Ethanolic extract showed highest activities against Candida albican, followed by Staphylococcus aureus and Klebsiella pneumoniae with 21.5mm, 19.5 mm each respectively. The same patterns of of inhibition was also observed in N-hexane extract. The antimicrobial effect of the two extracts were statistically not significant. The extracts had minimum concentration that ranged between 150mg/ml and 200mg/ml. The ethanolic extract showed more inhibitory effects compare to the aqueous and n- hexane extracts. The ethanolic extract found to contain highest quantity of phytochemicals while aqueous extract has lowest amount of the phytochemicals. It is therefore can be affirmed that Monodora myristica seed extracts could be exploited as therapeutic agents to drug resistant microorganisms.

Antimicrobial characteristics and biocompatibility of the surgical sutures coated with biosynthesized silver nanoparticles

Surgical sutures play important role during the wound healing of the surgical sites which are known to be sensitive to microbial infections. Silver nanoparticles (AgNPs) have been recently used as promising agents against multiple-drug resistant microorganisms. This study was designed to coat the sutures with silver nanoparticles obtained via a green synthesis approach. Microbial-mediated biological synthesis of AgNPs were carried out ecofriendly using Streptomyces sp. AU2 cell-free extract and deposited on silk sutures through an in situ process. Sutures coated with biosyntehsized AgNP (bio-AgNP coated sutures) were characterized using Scanning Electron Microscopy (SEM) and elemantal analysis were carried out using Energy Dispersive X-ray Spectroscopy (EDS). The silver amount released by the bio-AgNP coated sutures was calculated by Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) throughout a degradation process. Antimicrobial potential of the bio-AgNP coated sutures was determined against common pathogenic microorganisms Candida albicans, Escherichia coli and Staphylococcus aureus. To determine the biocompatibility/cytotoxicty of the bio-AgNP coated sutures, the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) assay was used through an indirect test method; that the elutions obtained by the extraction of the sutures at 1, 4, 8 and 10. days and were placed in contact with 3T3 fibroblast cell culture. To best of our knowledge, this is the first report about coating of the nonabsorbable silk sutures with silver nanoparticles biosynthesized using a microbial extract.

Biosynthesis, Characterization of Some Combined Nanoparticles, and Its Biocide Potency against a Broad Spectrum of Pathogens

The development of environmentally benign procedures for the synthesis of metallic nanoparticles (NPs) is a vital aspect in bionanotechnology applications for health care and the environment. This study describes the biosynthesis of Ag, Co, Ni, and Zn NPs by employing nanobiofactory Proteus mirabilis strain 10B. The physicochemical characterization UV-visible spectroscopy, scanning electron microscopy-energy-dispersive X-ray microanalysis (EDX), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS) technique including ζ potential, and polydispersity index (PDI) confirmed the formation of pure, stable monodisperse quasi-spherical oxide NPs of corresponding metals. The antimicrobial activity of biofabricated NPs was assessed against Gram-negative and Gram-positive bacteria, biofilm, yeast, mold, and algae via a well diffusion method. The results displayed significant antagonistic activity in comparison to their bulk and commercial antibiotics. Interestingly, the combined NPs exhibited promising synergistic biocide efficiency against examined pathogens which encourages their applications in adjuvant therapy and water/wastewater purification for controlling multiple drug-resistant microorganisms. To the best of our knowledge, no previous study reported the synthesis of semiconductor NPs by Proteus mirabilis and the biocide potency of combined NPs against a broad spectrum of pathogens not reported previously.

A Review on Green Synthesis, Biomedical Applications, and Toxicity Studies of ZnO NPs.

The advance of reliable and eco-friendly strategies for the development of nanoparticles is a fundamental key to the discipline of nanotechnology. Nanoparticles have been continuously evaluated and have been used in many industrial applications for a decade. In particular, the role of zinc oxide nanoparticles (ZnO NPs) has received a great interest because of various properties such as UV filter properties and photochemical, antifungal, high catalyst, and antimicrobial activities. Because of the high rate of poisonous chemicals and the extreme surroundings used within the chemical and physical methods, the green techniques have been adopted using plants, fungi, bacteria, and algae for the synthesis of nanoparticles. Therefore, this paper considers various green synthesis methods to provide the evidence of ZnO NP role to several applications, and in addition, biomedical applications and toxic effect were reviewed. Therefore, the paper used various secondary sources to collect the relevant review articles. From the findings, the green route of synthesis is rather safe and eco-friendly when compared to physical and chemical means of synthesis. On the other hand, its biomedical applications in this sector are increased day by day in various processes including bioimaging, drug delivery, biosensors, and gene delivery. With respect to its toxicity properties, ZnO NPs can act as smart weapons against multiple drug-resistant microorganisms and as a talented substitute for antibiotics.

Engineered Nanoparticles with Antimicrobial Property.

The urge for the development and manufacture of new and effective antimicrobial agents is particularly demanding especially in the present scenario of emerging multiple drug resistant microorganisms. A promising initiative would be to converge nanotechnology to develop novel strategies for antimicrobial treatment. These distinct nano scale properties confer impressive antimicrobial capabilities to nanomaterials that could be exploited. Nanotechnology particularly modulates the physicochemical properties of organic and inorganic nanoparticles, rendering them suitable for various applications related to antimicrobial therapy compared to their bulk counterparts. However, a major issue associated with such usage of nanomaterials is the safety concern on heath care system. Hence, a thorough put knowledge on biocompatible nanostructures intended for antimicrobial therapy is needed. A systematic review of the existing scientific literature is being attempted here which includes the properties and applications of a few nano structured materials for antimicrobial therapy and also the mechanism of action of nanomaterials as antimicrobial agents. Silver (Ag), Graphene, Quantum dots (QDs), Zinc oxide (ZnO) and chitosan nanoparticles are taken as representatives of metals, semiconductors, metal oxides and organic nanoparticles that have found several applications in antimicrobial therapy are reviewed in detail. An ideal anti microbial should selectively kill or inhibit the growth of microbes but cause little or no adverse effect to the host. Each of the engineered nanomaterials reviewed here has its own advantages and disadvantages. Nanomaterials in general directly disrupt the microbial cell membrane, interact with DNA and proteins or they could indirectly initiate the production of reactive oxygen species (ROS) that damage microbial cell components and viruses. Some like silver nanoparticles have broad spectrum antibacterial activity while others like cadmium containing QDs shows both antibacterial as well as antiprotozoal activity. Nano material formulations can be used directly or as surface coatings or as effective carriers for delivering antibiotics. Polycationic nature of Chitosan NPs helps in conjugation and stabilization of metallic nanoparticles which will enhance their effective usage in antimicrobial therapy.

ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES OF OCIMUM GRATISSIMUM L.

The development of antibiotic resistance in microorganisms is a global challenge for the clinicians, pharmacist and research scientists leading to development of new medicinal formulations that are effective and easily consumable. The plant yielding essential oil with chief constituent as eugenol has been identified as an important compound with strong inhibition of bacteria, and storage fungi. Ocimum gratissimum is an aromatic shrub occurring in warm tropical regions has been used in traditional medicine in India to cure various ailments in general and as an antimicrobial agent in particular. The literature surveyed reveals that the plant oil exhibit strong potentiality against gram negative and gram positive bacteria along with diverse human and plant fungi. As a natural product the plant oil is safer as food preservatives and stored grain protectant and has wide application in cosmetics and perfumery industries. This comprehensive review is attempted to provide the valuable information on antimicrobial activities of the plant essential oil that will be used to explore and develop a standard therapeutics system for the management of clinical and multiple drug resistant microorganisms.

Untreated Liquid Hospital Waste: Potential Source of Multidrug Resistant Bacteria

Antimicrobial resistance in both pathogenic and commensal bacteria is increasing steadily. Failure of antibiotic resistant bacteria containment is responsible for this expansion. Healthcare effluent acts as the store house of harmful infectious pathogens. Potential health risk includes spreading of diseases by these pathogens and wide dissemination of antimicrobial resistance genes. The present study was carried out to investigate the multiple-drug resistance among the bacterial strains that were isolated and identified from the effluents of Jessore Medical College Hospital & Jessore Queen’s hospital private limited. Identified bacteria were E. coli , Klebsiella spp., Enterobacter spp., Proteus vulgaris and Salmonella spp.. Occurrence of E. coli and Enterobacter spp. were found to have the highest percentages and present in majority of the samples. The identified organisms antibiotic resistant pattern were analyzed by agar disc diffusion method against 6 antibiotics. Results of antibiotic susceptibility test showed that all of the isolates were multi-drug resistant (e”4). From the study, we observed that 75% of the isolates were resistant to amoxicillin, followed by Ampicillin (64%), Chloramphenicol (31%), Gentamycin (29%), Nitrofurantoin (27%) and least resistant being Ciprofloxacin 23%. Among the isolates Salmonella spp. were showed highest rate of resistance against all the used antibiotics. The result denotes that, the identified bacteria have been well exposed to the tested antimicrobials and they have established mechanisms to avoid them. Therefore, proper waste water treatment plant should be established to diminish the risk of disseminating multiple drug resistant microorganisms for the safeguard of public health.Bangladesh J Microbiol, Volume 32, Number 1-2,June-Dec 2015, pp 21-24

Evaluation of the Activities of Antimicrobial Agents on Multi-drug Resistant Gram Positive Bacteria Isolated from Intensive Care Units

Multi-drug resistant Gram-positive bacteria are responsible for nosocomial infections. It is important to show the minimal inhibitory concentrations and new antibiotic resistance profiles of these bacteria to antimicrobials which are commonly used in treatment. The aim was to evaluate the new and more efficient antibiotics minimal inhibitory concentrations which can be used for treatment of Gram positive multiple drug resistant microorganisms. In this study, 337 Gram positive bacterial strains were isolated from clinical samples of 192 patients who were hospitalized at intensive care units. Minimum Inhibitory Concentration (MIC) values of antibiotics were investigated in 72 Gram positive bacterial strain. Broth macrodilution and disc diffusion methods were performed to evaluate the activities of antibiotics against Gram positive bacteria. All the 72 Gram positive bacterial strains including 38 coagulase negative Staphylococci, 18 Staphylococcus aureus and 16 Enterococci strains were sensitive to tigecycline, linezolid and daptomycin. All coagulase negative staphylococci and Staphylococcus aureus strains were sensitive to vancomycin and teicoplanin. Additionally, 2 Enterococci strains were resistant to vancomycin, while 1 strain was resistant and 1 strain was intermediately sensitive to teicoplanin. Vancomycin, teicoplanin, tigecycline, linezolid and daptomycin might be useful and good alternative for the treatment of multi-drug resistant bacterial infections. Different antibiotic resistance profiles and the MIC’s of antibiotics should be searched for the treatment of intensive care unit patients.

Peptidomimetics and their Applications in Antifungal Drug Design

The antimicrobial peptides represent diverse structures for drug design. They have been looked at as potential sources of new antimicrobial drugs to combat the increasing threat posed by multiple drug resistant microorganisms. Unfortunately, peptides themselves provide inferior drug candidates because of their low oral bioavailability, potential immunogenicity, poor in vivo metabolic stability, high molecular weight and most importantly being exposed by enzymes like proteases. Recent efforts to resolve disadvantageous peptide characteristics, and thus generating practical pharmaceutical therapies, have focused on the creation of non-natural peptide mimetics. Peptidomimetic molecules may have reduced immunogenicity and improved bioavailability relative to peptide analogues. Also the artificial backbone makes most peptidomimetics resistant to degradative enzymes thus increasing the stability of peptidomimetic drugs in the body. In this article, after introducing antifungal peptides, benefits and limitations, and peptidomemetics usage are discussed and applications in drug discovery process and antifungal research will be presented.

Characterization and management of solid medical wastes in the Federal Capital Territory, Abuja Nigeria.

Medical establishment such as hospitals and research institutes generate sizable amount of hazardous waste. Health care workers, patients are at risk of acquiring infection from sharps and contamination of environment with multiple drug resistant microorganisms if wastes are not properly managed. To characterize types and evaluate waste disposal techniques employed in the management of solid medical wastes in five selected hospitals in the Federal Capital Territory, Abuja. This was a cross section study involving the use of questionnaires, in-depth interview, meetings, discussions and participant observed strategy. It also involved the collection, sorting (segregation), identification and characterization and weighing of waste types from wards and units in the selected hospitals. The average waste generation rate per bed/day was determined and found to be 2.78 kg of solid waste, 26.5% of the total waste was hazardous in nature. Waste segregation was found not to be practiced by any of the hospitals surveyed, 18.3% of the hospitals incinerated waste in a locally built brick incinerator; 9.1% bury; 36.3% burn waste in open pits while 36.3% dispose of a waste into municipal dumpsites. Waste management officers do not have formal training in waste management techniques; and hospital administrators pay very little attention to appropriate management of medical waste. Therefore, we must educate waste generators of their responsibility to properly manage the waste so that their staff, patients, environment and community is protected.

Managing multiple drug-resistant microorganisms in a rehabilitation facility

Managing multiple drug-resistant microorganisms in a rehabilitation facility

Multiple drug resistance in bacterial isolates from liquid wastes generated in central hospitals of Nepal

Healthcare liquid wastes are the reservoirs of harmful infectious agents such as the pathogens and multiple drug resistant microorganisms. Potential infectious risks include the spread of infectious diseases and microbial resistance from health-care establishments into the environment and thereby posing risks of getting infections and antibiotic resistance in the communities. The objectives of this study were to assess the bacterial load of healthcare liquid waste generated in central hospitals and to explore the antimicrobial resistance pattern of these bacterial isolates. A descriptive study was carried out in 10 conveniently selected central hospitals of Nepal during the period of May to December 2008. Effluent specimens from each hospital were subjected to total viable count studies by spread plate method in nutrient agar plate and incubated for 24 hours at 37 °C using standard laboratory protocol. Similarly, all the specimens were cultured in Mac Conkey Agar media supplemented with 30 μg/ml of Chloramphenicol and 20 μg/ml of Gentamycin for the enumeration of multiple drug resistant (MDR) bacteria, which were further subjected to in-vitro antibiotic susceptibility test by modified Kirby Bauer disc diffusion technique for resistance patterns. Total viable counts of hospital effluents significantly exceeded the standard heterotrophic plate count (p=0.000). Similarly, the numbers of multiple drug resistant bacteria were alarmingly high in three (more than 30% in 2 and 50% in 1) hospitals of this study. Drug resistant hospital effluent isolates showed simultaneous resistance for most of the antibiotics including Penicillin, Cephalosporin, Cotrimoxazole, Gentamycin and Quinolones. Healthcare liquid wastes were laden with MDR bacteria and seemed to pose a huge public health threat in the transfer of such resistance to the bacterial pathogens causing community acquired infections, thereby limiting our antibiotic pool.