Anti-Infective Agents - Volume 18, Issue 1, 2020

Polyphenols have received high attention due to their biological functions. Pomegranate (Punica granatum L.) is a rich source of polyphenols such as tannin, ellagitannin, flavonoids and other phenolic acids. The potential therapeutic uses of pomegranate appear to be wide diversity. Pomegranate contains strong antioxidant activity, and antimicrobial properties, with potential health interests. This review has been performed on a method of systematic narrative review on the antimicrobial potency of different parts of pomegranate. A search was performed in PubMed, Web of Science, Science Direct, Scopus and Google Scholar from 1986 to 2018 to obtain related studies. The aim of this review present an overview of the aspect and advantages of Punica granatum L. and summarize the present data on the pomegranate anti-microbial activity in in-vitro and in-vivo tests, animal trial systems and human clinical trials. Also, this review discussed the pomegranate extracts activities and their future application. The findings of this review support that the pomegranate might be possible to use in the control and potential therapeutics of some microbial infections. This review highlights the new researches on the anti-microbial activities of pomegranate.

Introduction: A new series of benzothiazole azo-ester derivatives was synthesized by using Steglish esterification reaction. Methods: All the synthesized compounds were screened for their anti-TB activities by in vitro microplate Alamar Blue assay method against M. tuberculosis (H37RV strain). All the compounds showed activities and their MIC values were over the range of 1.6 μg/mL to 50 μg/mL. The compounds 4d and 4j showed superior activity with MIC 1.6 μg/mL compared to the standard drug Streptomycin (MIC 6.25 μg/mL), Pyrazinamide (MIC 3.125 μg/mL) and Ciprofloxacin (MIC 3.125 μg/mL). Results: Molecular docking study was carried out with enoyl acyl carrier reductase (InhA) of M. tuberculosis and decaprenyl phosphoryl-D-ribose oxidase (DprE1). Conclusion: These studies showed that these compounds have more interaction with InhA protein whereas some compounds could not be docked into DprE1.

Introduction: A biologically active benzimidazole synthesis was carried out at laboratory scale in order to reduce environmental pollution as well as to identify effective synthetic route. Methods: In this connection optimization was performed by Central Composite Rotatable Design (CCRD) to develop experimental data through Response Surface Methodology (RSM). The optimization of title analogue was performed by RSM which led us to the identification of high quality of synthetic yield. The effects of four independent parameters [1-5 mol of oxobutanoic acid (X1), 1-5 mol of thionyl chloride (X2), 1-5 mol of imidazol-2-yl-4-oxobutanoyl chloride (X3), and 1-5 mol of 4-nitro aniline (X4) were taken into optimize the synthetic yields of title scaffold. Results and Conclusion: A result on randomly generated benchmark and real values such as percentage yield, λmax and Retention Time (RT) of title compound are found to be highly significant. The present model connected into maximizing percentage yield of title scaffold with developed optimal set. The high significant benzimidazole was screened for their MTB activity against MTB H37Ra strain by MABA screening.

Background: Chitosan, chitosan nanoparticle, ethanolic extracts of Anacyclus pyrethrum root and Cyperus rotundus rhizome were evaluated against plasmid mediated multidrug resistance of Enterococcus faecalis, Staphylococcus aureus and Bacillus sp. isolated from unstimulated saliva of chronic periodontitis. The main aim of the current study centres the reduction of antibiotic consumption and the development of natural compounds to combat multidrug resistance. Methods: Identification of bacteria, antimicrobial susceptibility, plasmid stability and plasmid curing was carried out for the characterization of resistance plasmids. Results: E. faecalis showed 89% of sensitivity to chitosan nanoparticle, chitosan 81%, C. Rotundus 69% and A. pyrethrum 62% for S. aureus, with the MIC >100 μg/ml. In comparison with the antimicrobials tested, maximum resistance to tetracycline (89%) for E. faecalis, is followed by ampicillin (87%) and tetracycline (81%) for S. aureus. Meanwhile, chloramphenicol and tetracycline (80%) for Bacillus sp. The plasmid stability for E. faecalis (20%), S. aureus (<4%) and Bacillus sp. (16%). The order of stability corresponding to the broth media is LB > BHI > nutrient for E. faecalis, S. aureus but similar in LB and nutrient broth for bacillus sp. The maximum plasmid curing efficiency of chitosan for S. aureus (76%), Chitosan nanoparticle for E. faecalis (88%), A. pyrethrum for S. aureus (73%), C. rotundus for E. faecalis (87%). The order of plasmid curing efficiency is chitosan nanoparticle>C. rotundus>chitosan>A. pyrethrum. Conclusion: Chitosan, Chitosan nanoparticle, C. rotundus, and A. pyrethrum offered a greater potential in eliminating plasmid mediated resistance acquired by periodontal pathogens, thus addressing this crisis in dentistry.

Background: The fight against infectious diseases includes two main components – immediate direct anti-infective action and stimulation of one's own immunity. Objective: In this study, we investigated the properties of diamond nanoparticles modified with gold. The use of such gold nanoparticles as indirect anti-infectious agents and immunostimulators has certain prospects. Materials and Methods: Gold hydrosols were synthesized by the reduction in an aqueous solution of gold (III) with sodium citrate (Na3Cit) under heating. Modification procedure of nanodiamond by gold requires incubation, a small sample of nanodiamond in a defined volume of a gold sol for about 24 hours in a dark place. We use human blood cells as test objects. The reaction of blastic transformation of lymphocytes was applied here as a test of biological actions of modified nanodiamond. Results: Modified nanodiamond do not have a toxic influence on blood cells. Modified nanodiamond possesses stimulation effects on spontaneous proliferation of lymphocytes and does not significantly affect phytohemagglutinin-induced proliferation. Nanodiamond slightly increases phagocytosis parameters of neutrophil leucocytes. Conclusion: Thus, results showed that the nanodiamond modified by gold possesses immunostimulating activity, increases the phagocytic activity of neutrophilic leukocytes and stimulates lymphocytes in the spontaneous proliferation test. Gold-modified nanodiamond could be considered as a non-direct anti-infective agent through immune stimulation.

Introduction: The synthesis of copper soap (laurate), and its complex with 2-amino 6- methylbenzothiazole and their elemental and spectral analysis have been done for comparative studies using IR, NMR, Mass and ESR spectra. Methods: The fungicidal activities, with reference to Alternaria alternata and Aspergillus niger at different concentrations by P.D.A. technique were also studied. Results and Conclusion: The present research work comprises detailed thermal analysis using TGA technique to determine their kinetic and thermodynamic parameters by applying various equations like Freeman Carroll, Coats-Redfern equation, Horowitz-Metzger equation, Broido equation, Piloyan–Novikova equation.

Background: Antibiotic resistance is today one of the most serious threats to global health, food security and development. Due to the growing number of infections, treatment becomes more difficult, if not impossible, because of the loss of antibiotic efficacy. Objectives: In the present investigation, the chemical composition of essential oils of Ammoides verticillata and Satureja candidissima and their synergistic effects on antimicrobial activities were investigated. Methods: The chemical composition of the essential oil was analyzed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectroscopy (GC/MS). The antimicrobial activity of the essential oils was investigated using dilution-agar method against nine bacterial strains three Gram-negative Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853) and Salmonella typhi (ATCC 14028), and six Gram-positive: Staphylococcus aureus (ATCC 43300,) Clostridium sporogenes (ATCC 19404), Bacillus subtilis (ATCC 6633), Enterococcus faecalis (ATCC 7314), Lactobacillus rhamnosus (ATCC 53103) and Bacillus cereus (ATCC 14579). Results: The essential oil of A. verticillata was characterized principally by carvacrol (44,3%), Limonene (19,3%) and p-cymene (19,2%). The constituents identified of S. candidissima essential oil were principally oxygenated monoterpenes represented by pulegone (70,4%). The essential oil of A. verticillata had a good antimicrobial activity against four bacterial strains (Escherichia coli, Salmonella typhi, Lactobacillus rhamnosus and Bacillus cereus) with MIC and MBC values between 0.2-0.4 μl/ml and 0.2-6.2 μl/ml, respectively. While, S. candidissima essential oil had moderate antimicrobial activities against all strains with MIC and MBC values between 1.5-6.2 μl/ml and 6.2-12.5 μl/ml, respectively. The results of antimicrobial activity of essential oils blend presented higher antimicrobial activity against all tested bacteria with MIC and MBC values between 0.3-1.5 μl/ml and 0.4-6.2 μl/ml, respectively. Conclusion: The essential oils blend presented high antimicrobial activity compared to virgin oils. This activity can be due to the association of active compounds such as carvacrol and pulegone. These findings provide a new source of drugs that may help in therapy to lead to the development of a new treatment based on a combination of these essential oils against gram-negative and gram-positive bacteria that continue to pose a threat to public health.

Background: Usnic Acid has been progressively reported in the literature as one of the chiefly significant lichen metabolites exemplified by an ample diversity of applications such as antimicrobial, antifungal, antiviral, antiprotozoal agents, etc. Herein, we shed a light on nosocomial infections and formulated topical microspheres loaded with Usnic acid for improved antimicrobial activity. Recent patents and novel researches were referred to pursue the present work. Methods: Usnic acid embedded Eudragit microspheres were designed applying solvent evaporation method, investigated for topography and drug-polymer compatibility studies. Dialysis bag method was utilized for studying drug release kinetics. In vitro antibacterial assay was carried out against the virulent bacterial strain of Staphylococcus aureus using the disc diffusion method. Results: Topography studies revealed the formation of regular, micro-sized, smooth surface microspheres. Well defined and specific structural peaks were obtained from FTIR and TGA studies, revealing drugpolymer compatibility. The dissolution profile suggested Korsmeyer Peppas kinetic and Fickian kind of diffusion from microspheres. The pre-eminent activity of formulated microspheres was visualized from the disc diffusion study against Staphylococcus aureus. Conclusion: The strong biological activity of Usnic acid –loaded Eudragit RS and Eudragit RL microspheres provides a promising application for corresponding material as a bactericidal agent for the alleviation of nosocomial infection. Findings paid attention to the potential of usnic acid microspheres for effective treatment of dermal and nosocomial infections caused by S. aureus.