Antibacterial Sensitivity Research Articles

Synthesis, Characterization, and Antibacterial Evaluation of Heteroleptic Oxytetracycline-Salicylaldehyde Complexes

A new series of mixed ligand complexes of Cd(II) and Mo(V) were successfully synthesized by refluxing the mixture solution of oxytetracycline hydrochloride (OTC.HCl) with an aqueous and alcoholic solution of metal (M = Cd(II) and Mo(V)) salts and an alcoholic solution of salicylaldehyde (Sal). The complexes were characterized by modern analytical and spectral methods such as elemental microanalysis, pH, conductivity, surface tension, viscosity, melting point, and spectral methods such as FT-IR, NMR, electronic absorption, SEM, and mass spectrometry. Conductivity measurements of the complexes revealed their electrolytic nature. The kinetic and thermal stabilities were investigated using thermogravimetric and differential thermal analysis techniques. Thermodynamic and kinetic parameters such as E∗, ΔH∗, ΔS∗, and ΔG∗ were calculated from TG curves using the Coats–Redfern method. Geometry optimization of the proposed structure of the complexes was achieved by running MM2 calculations in a Gaussian-supported CS ChemOffice 3D Pro.12.0 version software. The final optimized geometrical energies for respective Cd-OTC/Sal and Mo-OTC/Sal complexes were found to be 923.1740 and 899.3184 kcal/mol. The electronic absorption spectral study revealed a tetrahedral geometry for the Cd-OTC/Sal complex and octahedral geometry for the Mo-OTC/Sal complex. The antibacterial sensitivity of the complexes was evaluated against three bacterial pathogens such as S. aureus, E. coli, and P. mirabilis using the modified Kirby–Bauer paper disc diffusion method. The antibacterial study revealed significant growth inhibitory action of the complexes.

Technological and probiotic potential of autochthonous lactic acid bacteria from spontaneously fermented dromedary milk

This work aimed to identify autochthonous lactic acid bacteria (LAB) from spontaneously fermented dromedary milk and explore their technological and probiotic properties in vitro. Analysis of the strains by 16S rDNA gene sequencing revealed four strains as Enterococcus faecalis, one strain as Enterococcus faecium, one strain as Lactococcus lactis, and four strains as Streptococcus pasteurianus. However, two strains (LEFS 42 and LEFS 55) showed a low 16S similarity (97.60% and 97.54%, respectively) with the type strain Streptococcus suis 92-2742T. All the tested LAB strains possessed acidifying and proteolytic capacities. Most of them were lipolytic (83.33%) and had the ability to produce exopolysaccharides (91.67%). All the studied LAB strains were non-hemolytic and exhibited antibacterial activity and sensitivity toward five antibiotics. Streptococcus sp. LEFS 55 had the highest hydrophobicity, autoaggregation, and coaggregation abilities. Moreover, all the isolated strains were able to resist simulated human gastrointestinal tract conditions and scavenge DPPH and ABTS radicals. Practical applications Nutritional and medicinal values of dromedary milk can be further increased after fermentation. Commercially available starter cultures are from bovine-based dairy industry being not competitive with endogenous microbiota of dromedary milk, which might not give a desirable final product. However, to date, few attempts have been performed to isolate and characterize lactic acid bacteria from spontaneously fermented dromedary milk. Besides, the probiotic potential of autochthonous lactic acid bacteria from fermented dromedary milk remains unexplored. Hence, this study aimed to identify autochthonous lactic acid bacteria from spontaneously fermented dromedary milk and to investigate their technological and probiotic potential. The isolation of autochthonous lactic acid bacteria with technological and probiotic properties from dromedary milk allows the production of fermented dromedary milk with functional properties and the diversification of dromedary milk products.

Sensitivity Pattern of Gram Negative Bacteria Contaminating Traumatic Wounds: A Retrospective Study in a Tertiary Care Hospital of Kathamandu Valley

Introduction: Gram negative bacteria are commonly involved in wound infections and are significantly associated with morbidity and mortality because of increasing resistance to commonly used antibacterial agents. This study aims to evaluate the pattern of antibacterial sensitivity of the gram negative bacteria from wound swabs of accidental trauma cases.
 Methods: This retrospective study was done by collecting all the culture positive reports for wound swabs of accidental wounds from the microbiology laboratory and analyzing the reports showing growth of gram negative bacteria for frequency of sensitivity to commonly used antibacterial agents. 
 Results: Culture positivity rate was 21.95% with growth of gram negative bacteria in 79.7% of cases. The most commonly isolated organism was Escherichia coli being 41.3% among gram negative isolates. Highly resistant bacteria were E. coli, Klebsiella pneumoniae and Acinetobacter spp.
 Conclusions: As there is low culture positivity rate for wound swabs obtained before washing the wounds inflicted by accidental trauma, prolonged routine use of prophylactic antibiotic is not justified. Thoroughly washing the wound is very likely to decrease the rate of wound infection further and reduces the need of antibacterial agents. Culture and sensitivity test should guide the treatment when wound is infected because highly resistant gram negative organism may be involved in such cases.

Antibacterial Sensitivity and Detection of Virulence Associated Gene of Pasteurella multocida Isolated from Rabbits

Antibacterial Sensitivity and Detection of Virulence Associated Gene of Pasteurella multocida Isolated from Rabbits

Sensitivity of <i>Streptococcus</i> <i>viridans</i> to antibacterial agents in HIV-positive patients coupled to respiratory diseases

The streptococcus group consists of multiple species of globular Gram-positive facultative anaerobic bacteria, the classification of which is based on assessing their capacity to erythrocyte hemolysis. The viridans group streptococci produce a green coloration being a part of normal microflora in the oral cavity. However, in case of developing immunodeficiency states, oncology, and neutropenia, this pathogen can cause diseases such as bacteremia, sepsis, endocarditis, as well as pneumonia in some cases. Respiratory diseases commonly require medical assistance in HIV-infected patient cohort. The role of commensal S. viridans in development of bacterial diseases in HIV-infected patients remains poorly examined. A potential association between S. viridans and other bacterial communities, including pathogenic microorganisms is obscure. In addition, it might be worth evaluating sensitivity of S. viridans to antibacterial agents in regions with high HIV infection incidence. The aim of the study was to evaluate sensitivity to antibiotics in sputum viridans group streptococci collected from HIV-infected patients with symptomatic pneumonia. Materials and methods. The data on sputum microbiological study conducted within the 01.01.2012—01.01.2019 interval were collected from all HIV-infected patients with suspected pneumonia (n = 684) and analyzed at the Infectious Clinical Hospital No. 1 named after D.M. Dalmatov, among which S. viridans was detected in 193 patients (28.2%). Bacteriological examination of patient samples was conducted to isolate pure bacterial culture by using standard methods. Next, S. viridans was assessed for sensitivity to antibacterial agents (n = 78) according to the 2018 clinical recommendations. Initially, antibiotic resistance was assessed by disk-diffusion method as a routine approach broadly used in clinical laboratory. After that, the minimal inhibitory concentration was measured by using AutoScan 4 Microscan analyzer (bacteriological semi-automatic analyzer, Beckman Coulter, USA) to identify and determine antibacterial sensitivity. Results. A disk-diffusion method allowed to find in sputum samples streptococci resistant to penicillin in 28.2% cases, ampicillin — in 42.3% and cefazolin — in 43.6%. While assessing the minimal inhibitory concentration for antibacterial agents, similar data were obtained. Good sensitivity was found for cefotaxime, ceftriaxone, cefepime, fluoroquinolones and vancomycin.

The Evaluation of Antibiotic Resistance and nalB Mutants in Pseudomonas eruginosa Isolated from Burnt Patients of Shohada Mehrab Yazd Hospital Burn Ward.

Due to extensive damage to the skin, burn victims may acquire life-threatening infections. Though the skin primarily protects against microbial invasions, a large number of bacteria, fungi, and viruses can be isolated from burn patients, specifically Pseudomonas aeruginosa, a gram-negative bacterium with both intrinsic and acquired antibiotic resistance (AR) properties. nalB mutations can be found on the mexR in the P. aeruginosa chromosome. This mutation can induce overexpression of the mexAB-oprMoperon, and affect the MexAB-OprM efflux pump, which removes antimicrobial agents from the bacterial cell. Identifying nalB mutants can be useful for monitoring factors affecting AR. In this study, 70 P. aeruginosa isolates identified from burn patients and antibacterial sensitivity was evaluated using the Kirby-Bauer method. We also investigated nalB mutations in samples using molecular methods including Polymerase reaction chain (PCR) and Sequencing. We identified nalB mutations in 16 isolates. We also found that the increasing effect of nalB mutants induces hyper production activity of MexAB-OprM resulting in AR. Overall, these findings compliment the findings of previous reports. According to the resistance patterns of the samples, both Amikacin and Ciprofloxacin showed the highest resistance (%). Further, the relationship between Ciprofloxacin resistance and nalB mutations was statistically significant (p= 0.016). The results confirm that the increasing effect of nalB mutants on hyper production activity of MexAB-OprM leads to AR.

Oral Plus Topical Administration of Enrofloxacin-Hydrochloride-Dihydrate for the Treatment of Unresponsive Canine Pyoderma. A Clinical Trial.

Simple SummaryThis is the first report on the clinical use of a new derivative of enrofloxacin (enrofloxacin HCl-2H2O or enro-C) for the treatment of canine unresponsive deep-pyoderma (UDCP), utilizing a dual scheme, i.e., 10 mg/kg/day in capsules, plus the topical administration of enro-C, prepared as an 0.5% alginate gel, thrice per day. Fifty-five cases of UDCP were treated successfully in a one-year study. Mean days of treatment were 8 to 12, for either severe or very severe cases, respectively. Complete success was recorded and no recurrences after a two-month clinical follow up were registered. It is here proposed that the dual treatment, the potency of enro-C and the theoretically high concentrations of the active principle in the lesions may explain these findings. Further research is needed to define the bacteriological status of the pathogens found, and the impact of this treatment in bacterial resistance.An outpatient clinical trial on unresponsive deep-bacterial canine pyoderma (UDCP), without a control group, is presented. The chosen treatment was implemented with a new crystal-solvate of enrofloxacin (enrofloxacin HCl-2H2O or enro-C), in a dual scheme, i.e., 10 mg/kg/day PO, plus its topical administration, prepared as 0.5% in an alginate gel, thrice per day. Fifty-five cases that were unsuccessfully treated previously with another antibacterial drug, were selected and then classified as severe or very severe, according to a clinical score tailored for this trial. Aerobic bacteriological cultures of skin lesions and antibacterial sensitivity tests, were performed. Hematological status, liver, and kidney functions were determined before and after treatment. A complete success was obtained in 32 severe and 23 very severe, cases. The main bacterial isolates were: Staphylococcus intermedius (19/99), Staphylococcus pseudintermedius (16/99), Staphylococcus epidermidis (15/99), Staphylococcus pyogenes (14/99), Staphylococcus saprophyticus, Streptococcus sp., and others including Pseudomonas aeruginosa (6/99). The average duration of treatment was 8.03 days ± 2.1 SD and 12.0 ± 2.4 days, for dogs with severe or very severe UDCP, respectively. The adverse effects caused by enro-C were inconsequential and the hematological tests showed no deviations from normality. The use of enro-C administered dually to treat UDCP, is considered safe and highly effective.

Solution properties and comparative antimicrobial efficacy study of different brands of toothpaste of Nepal

BackgroundThe main objective of this study is to compare the effectiveness of toothpaste formulations in giving total protection to the oral cavity. So, three important solution properties: surface tension, conductivity, and pH measurements, have been investigated for eight kinds of commercial herbal and non-herbal based toothpaste of Nepal. The study was extended to evaluate the antibacterial efficacy of toothpaste formulations against the Gram-positive bacteria Staphylococcus aureus (S. aureus) and Gram-negative bacteria Escherichia coli (E. coli), and this was done by standard agar well diffusion technique. Amikacin (30 μg/disk) was used as a positive control to compare the antibacterial potency of the investigated toothpaste.ResultsThe surface tension of all toothpaste formulations increased with the decrease in concentration. However, the conductivity of the formulations decreased with the decrease in concentration. The highest pH of 8.24 was recorded for Dabur Super Salt (DSS) and all values were found to be higher in tap water solutions. All toothpaste formulations showed significant growth inhibition against both S. aureus and E. coli. The overall antibacterial sensitivity of Dabur Red (DR) is higher for S. aureus. The solid material content was found to be highest for Dabur Herbal Gel (DHG) and lowest for Pepsodent (PD).ConclusionThe findings of the present study showed all toothpaste formulations as effective in inhibiting the growth of tested bacterial species. Toothpaste formulations were found slightly alkaline, which favors bacterial growth inhibition. Increasing surface tension and decreasing conductivity value of toothpaste relative to a decrease in concentration favor its desirable cleansing action.

Antimicrobial susceptibility of isolates of Salmonella enterica subsp. Enterica isolated in Ukraine during the period of 2014–2017

The results of the study of sensitivity to antibacterial drugs in isolates of Salmonella enterica isolated from poultry are shown in the article. Antibacterial sensitivity was determined by disc diffusion to such drugs: ampicillin, cefoperazone, ceftriaxone, ceftazidime, tetracycline, doxycycline, streptomycin, gentamicin, nalidixic acid, chloramphenicol, ciprofloxacin, trimethoprim. Growth retardation zones were interpreted according to the CLSI standard. Among the isolates tested, a significant percentage of isolates resistant to nalidixic acid and ciprofloxacin were found – (19 (63.3 %) and – 21 (70 %), respectively. A significant number of isolates were also resistant to beta-lactams. In particular, 37 isolates (64.9 %) were resistant to ceftazidime, and 36 (63.1 %) to ceftriaxone. However, ceftriaxone resistance was dominant among S. typhimurium isolates, whereas in Enteritidis this indicator was significantly lower. However, the highest resistance of the studied isolates were shown to the beta-lactam class – cefoperazone (70.17 %). Only 6 isolates (20 %) were sensitive to nalidixic acid but did not detect any isolates sensitive to ciprofloxacin. This is a significant problem because quinolones are used to treat invasive salmonellosis. In this study, 12 (40 %) isolates were sensitive to ampicillin, 9 (30 %) to cefoperazone, 10 (33.3 %) to ceftriaxone and 9 (30 %) to ceftazidime. The lowest number of strains was resistant to trimethoprim – 9 (30 %) and chloramphenicol – 8 (26.6 %). Unfortunately, the use of the latter is limited due to the possibility of serious side effects. Overall, the group of poultry isolates tested reflects a general upward trend in antibiotic resistance. The findings present new data on resistance and provide prospects for further studies on this aspect of salmonellosis.

Conductivity, Surface Tension, and Comparative Antibacterial Efficacy Study of Different Brands of Soaps of Nepal

The current study aims to evaluate the solution properties and antibacterial efficacy study of five different brands of toilet soaps of Nepal such as Okhati (OKT), Lifebuoy (LFBY), Lux (LX), Liril (LRL), and Chiuree Neem (NM). The evaluation of critical micelle concentration (CMC) and their thermodynamics and surface properties are also reported. This study was further extended to evaluate antibacterial efficacy against three pathogenic bacteria such as Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Proteus vulgaris (P. vulgaris) by disc diffusion technique, and it was done at four different concentrations of soap. The bioactive ingredients present in them provide antibacterial potency to cure various skin problems caused by bacterial pathogens. Similarly, the antibacterial potency of LFBY was found higher than other soaps. Based on these studies, we can simply take LFBY soap at the highest rank in regards to antibacterial sensitivity.

Isolation of Pathogenic Bacteria and Their Antibiotic Sensitivity Profiles in Hospitalized Febrile Neutropenic Children with Acute Lymphoblastic Leukaemia

Background: Acute lymphoblastic leukemia (ALL) is the commonest malignancies in childhood. Common obstacle in the treatment of ALL is febrile neutropenia and its complications. Objectives: To identify bacteria causing infection, their isolation rate and antibacterial sensitivity pattern in hospitalized febrile neutropenic children with ALL in different cycle of chemotherapy. Methodology: This observational study conducted in 2014 - 2015 in the department of paediatric haematology and oncology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka Bangladesh. Sixty febrile neutropenic episodes from 52 diagnosed cases of ALL aged 0 to18 years were included. Complete blood count, blood culture, urine microscopy and culture, serum alanine aminotransferase, serum creatinine were done in every patient. X-ray chest, stool microscopy and culture, pus, wound, throat and aural swab for culture & sensitivity were done in selective patient. Results: Bacterial infection was confirmed by culture in 15 (25%) episodes from 60 febrile neutropenic episodes. Fifteen (25%) organisms were isolated from the study subjects from sample of blood (60%), pus (13.3%), aural swab (13.3%), wound swab (6.7%) and throat swab (6.7%) respectively. All isolates were gram negative. The organism isolated were Klebsiella spp. 5 (33.31%), E. coli 4 (26.7%), Acinetobacter 3 (20%), Pseudomonas 2 (13.3%) and only one (6.7%) Enterobacter species. All the isolates of the Klebsiella spp., E. coli and Acinetobacter spp. were resistant to amoxicillin. All isolated E. coli were resistant to cotrimoxazole, ceftazidime, ceftriaxone, cefotaxime and ciprofloxacin, Acinetobacter spp. Isolated were 100% sensitive to imipenem, colistin sulphate & piperacillin-tazobactam and resistant to cotrimoxazole and cephradine. All Pseudomonas spp. showed 100% sensitivity to imipenem, amikacin, ciprofloxacin & colistin and resistances to ceftazidime. Conclusion: The species of Klebsiella were the predominant causative bacterial agent followed by Escherichia coli, Acinetobacter spp, pseudomonas spp. and Enterobacter spp. They showed resistance to commonly prescribed antibiotics ceftazidime, gentamicin, ceftriaxone & ciprofloxacin and sensitive to imipenem, colistin-sulphate & piperacillin-tazobactam.

Mesoporous x[Cu(II)O] nanoclusters dispersed and immobilized on y$$[\text {SiO}_{2}]$$ matrix: structure and effective controlled biocidal activity against Pseudomonas aeruginosa and Bacillus subtilis

Herein we report the synthesis of mesoporous nanostructures comprising copper (II) oxide $$\{x[\mathrm{Cu(II)O}]\}$$ immobilized on silica $${ y}[\mathrm{SiO}_{2}]$$ template for release of copper ions by precipitation via sol–gel technique. Three different specimens with increasing amount of Cu in the matrix with amount of Si being the same in all the samples, viz. ‘6Cu:5Si’, ‘4.5Cu:5Si’ and ‘3Cu:5Si’ where the numbers refer to the respective molar ratios of their respective domains, were prepared. Increase of crystallinity in the mesoporous material with increase in incorporation of copper domains consisting of CuO in $$\text {SiO}_{2}$$ matrix has been established. The average size of the CuO nanoparticle (NP) (domain) is 20–30 nm. The BET surface area has been found to be 276–390 $$\text {m}^{2}\ \text {g}^{-1}$$ and Langmuir surface area has been found to be 422–605.9 $$\text {m}^{2}\ \text {g}^{-1}$$ for the samples 5Si:3Cu–5Si:6Cu, respectively, having pore size of 4–6.5 nm. The cytotoxicity data show that the NPs are less toxic below concentration of $$125\ \upmu \text {g ml}^{-1}$$ . A steady increase in percentage of bacterial-‘Escherichia coli’, ‘Pseudomonas aeruginosa’ and ‘Bacillus subtilis’ cell death (indicated by decrease in optical density) due to increase in concentrations of NPs after incubation for 14 h, showing sensitivity even at very low concentrations (5–20 $$\upmu $$ g), has been observed. A comparative antibacterial activity test among the three prepared specimens has been reported, which shows better antibacterial activity with the lowest copper concentration. Better antibacterial sensitivity when compared with equivalent amount of commercial CuO is established.

The prevalence of E.coli isolated from primates in Alexandria Zoo

Out of 54 collected samples from apparently healthy zoo monkeys of different species reared in Alexandria Zoo. Forty four samples were positive for E. coli, with percentage of (81%). Bacterial isolation was carried out from rectalswabs.O158H4, O158H2, O158H5, O158H20; O18H2, O18H6; O114H2 and O78H6 serotypes were detected. phoA, Iss, eaeA and iutA virulence genes in isolated E.coli. All of 16 isolates were positive of E.coli isolates. IutA virulence gene was negative to all E. coli isolates. The antibacterial sensitivity test cleared that Enrofloxacine, Colistin, Ciprofloxacin, Cefotaxime, Gentamicin and Cefifur are drugs of choice. The results demonstrate that primates that were analyzed may carry and spread this bacteria, and preventive measures for human exposure should be determined, as these microorganisms are of public health concerns.

Antibacterial Sensitivity Profile of Lactobacillus Species and Characterization of Aflatoxin Producing Fungi Isolated from Yam and Plantain Flour

Antibacterial Sensitivity Profile of Lactobacillus Species and Characterization of Aflatoxin Producing Fungi Isolated from Yam and Plantain Flour

Qualitative phytochemical screening and antibacterial activities of <i>Basella alba</i> and <i>Basella rubra</i>

The study was carried out on Basella alba and Basella rubra leaves to further emphasize their importance and utilization as a support for promoting healthy diets in Nigeria. B. alba and B. rubra leaves were extracted in water:methanol (2:3) by maceration. Phytochemical screening and antibacterial sensitivity of the aqueous methanol extracts of both leafy vegetables were carried out using appropriate reference methods. The antimicrobial activity of the extracts against selected bacteria isolates were evaluated using agar well diffusion method at 30 mg/mL and 35 mg/mL concentrations. The results of the phytochemical screening revealed the presence of saponin, phlobatannin, cardiac glycoside, flavonoid and alkaloid in both extracts. Aqueous methanol extract of B. rubra exhibited in vitro antibacterial activity against all tested bacteria isolates; Clostridium sporogenes (NCIB 532), Streptococcus faecalis (LIO), Bacillus anthracis (LIO), Bacillus polymyxa (LIO) and Micrococcus luteus (NCIB 196). Clostridium sporogenes (NCIB 532) and Streptococcus faecalis (LIO) were resistant to the aqueous methanol extract of B. alba with no zone of inhibition shown. Streptomycin was used as the control at 1 mg/mL. The phytochemicals contained in these vegetables possess antimicrobial properties either in isolation or synergistically. Therefore, further research should be done to isolate and evaluate the mode of actions of the active principles that are important for the promotion of good health from these plant varieties.Keywords: Phytochemical screening; Antimicrobial sensitivity; Basella alba; Basella rubra; Streptomycin

IN VITRO ANTIBACTERIAL ACTIVITY OF MEDICINAL PLANTS TURMERIC, CHINNAMON, AND CLOVE AGAINST GM (+VE) AND GM (-VE) BACTERIA

Objective: Various diseases are caused by different pathogenic microorganisms. Antibiotics are being used for treatment of these infectious diseases, yet unpredictable utilization of it leads towards antibacterial resistance. It is required to discover better approaches to battle against antibacterial resistance. Therefore, the study aimed to detect antibacterial sensitivity of ethanol extracts of Curcuma longa (turmeric), Cinnamomumzeylanicum (clove) and Syzygiumaromaticum (cinnamon) against Syaphylococcus aureus and E coli.
 Methods: Prior to sensitivity testing, ethanol oils were extracted by an electric blender and each of the bacteria strains were cultured onto blood agar plate. Antibacterial activity was tested by agar well diffusion method where three different concentrations (50 μl, 75 μl and 100 μl) of selected plants extract were used so far as to measure the inhibition zone. Inhibition zone of the ethanol extract of these plants were calculated where three were found to be sensitive against Syaphylococcus aureus and E coli.
 Results: Greater inhibition zone 14.5 mm, 18.25 mm, 21.5 mm at100 μl against Syaphylococcus aureus in case of cinnamon whereas the least inhibition zone was showed by turmeric and it was 9.00 mm, 11.00 mm, and 12.75 mm at 100 μl extract against E. coli.
 Conclusion: Overall, all the ethanol extracts were found to effective against these two bacteria but cinnamon can be used as more effective antibacterial agent in both human and veterinary field after the toxicological test.

Antimicrobial activity of the aqueous and methanolic extracts of <i>Sesamum radiatum</i> (Schum and Thonn.)

Sesamum radiatum (Schum and Thonn.) is a leafy vegetable belonging to the family Pedialiaceae, it is used traditionally in the treatment of conditions such as diarrhoea, dysentery and fungal infections.This study investigated the phytochemical constituents and the antimicrobial activity of Sesamum radiatum (Schum and Thonn.). The pulverized plant material was subjected to cold marceration using distilled water and methanol for the aqueous and methanolic extracts, respectively. The plant extracts were further subjected to phytochemical screening using standard procedures and in vitro antibacterial sensitivity tests using the disc diffusion method. Zones of inhibition, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined. Flavonoids, terpenoids, cardiac glycosides and cardenolides were found in both the aqueous and methanolic extracts. The results of the in vitro antimicrobial susceptibility test showed that the aqueous extract inhibited the growth of Candida albicans at the highest concentration of 600 mg/ml with a zone of inhibition of 8.00±0.00 mm while the remaining microorganisms were resistant at all the concentrations. The methanolic extract inhibited the growth of Salmonella typhi at concentrations of 200 mg/ml, 400 mg/ml and 600 mg/ml and Pseudomonas aeruginosa at concentrations of 400 mg/ml and 600 mg/ml. In conclusion, the aqueous extract of Sesamum radiatum showed antifungal activities which may justify its folkloric use and the methanolic extract inhibited the growth of S. typhi which also justifies its use traditionally, in the treatment of dysentery and diarrhea.Keywords: Antimicrobial, Phytochemical constituents, Sesamum radiatum, MIC, MBC

Third Order Non-linear Optical Susceptibility (χ(3)) and Evaluation of Antibacterial Activity of Cu-Doped ZnSe Nanocrystals Fabricated by Hydro-Microwave Technique

In this work, Cu-doped ZnSe nanoparticles (NPs) at the presence of different Cu contents and also with/without 6 min microwave irradiation were fabricated in aqueous medium, and then some optical properties and also their antibacterial properties against two gram-positive bacteria of Staphylococcus aureus and Bacillus cereus were investigated, employing disc-diffusion method. To fabricate these NPs, Se ion source was provided from the interaction between Se and NaBH4, and zinc acetate was used as Zn ion source. At the fixed pH of 11.2, thioglycolic acid was used as surfactant to prevent agglomeration of NPs. Previously reported results of X-ray diffraction characterization and UV-visible spectroscopy of solutions containing nanoparticles, show the range of 1.94–2.14 for particles size and 3.50–3.65 eV for energy gap. In this research, non-linear optical susceptibility of ZnSe and ZnSe:Cu nanoparticles have been determined; results imply that these nanoparticles have a high potential in optical and optoelectronic applications and among them, sample owing 1.5% of impurity and so owing the highest χ(3), is an optimum candidate in optical applications. Results of the present research confirm that nonlinear optical susceptibility is in inverse relation with the energy gap and increase with increasing of Cu%. To explore the antibacterial activity of the present samples, first Staphylococcus aureus and Bacillus cereus bacteria were inoculated on Muller–Hinton–Agar culture, and then the loaded discs by nanoparticles were placed on them. After 18 h from the incubation, the inhibition zone diameters (their antibacterial sensitivity) were measured for each bacteria. Results of this research imply on that these nanoparticles have considerable antibacterial activity against the gram-positive bacteria of Staphylococcus aureus and Bacillus cereus, and have the usage ability in the field of antibacterial drugs. During this assessment, increase in impurity content resulted in improvement of antibacterial potential, especially the more efficiency on Staphylococcus aureus. In addition, it was shown that increase of the concentration (loading volume of solution containing NPs) lead to increase of bacterial growth inhibition. Results confirm that the optimal antibacterial activity is devoted to the 0.75% Cu-doped nanoparticles on Staphylococcus aureus. Also the undoped sample prepared under 6 min microwave irradiation had the highest antibacterial activity against the Bacillus cereus. In brief, studied NPs show excellent bactericidal and optical activity, introducing them as promising bio-opto-materials.

Fresh Garlic Extract has a Synergistic Effect with Antibiotics on ESBLs Producing E. coli Urinary Isolates

Aim: Extended spectrum beta-lactamases (ESBLs)-producing bacteria often exhibit a multidrug- resistant phenotype limiting the therapeutic options available to the clinician. This study was conducted to investigate the antibacterial susceptibility pattern of ESBL producing E. coli isolates and evaluation of the antibacterial activity of Garlic extract against it.
 Study Design: The study was carried out using antibiotics powder and Garlic extract.
 Place and Duration of Study: At the microbiology lab, Faculty of Medicine, Minia University between January 2017 to August 2018. 
 Methods: The study was carried on 55 ESBL producing E. coli isolates isolated from patients with urinary tract infections (UTI). Screening and confirmation for ESBL was done according to clinical and laboratory standard institute guidelines (CLSI) guidelines. The antibacterial sensitivity to a panel of antibiotics and Garlic was performed by tube dilution method.
 Results: The results of antibacterial susceptibility testing of ESBLs-producing E. coli isolates in our study showed a higher degree of resistance to the tested antibiotics. In the present study, Garlic showed an inhibitory effect on ESBLs- producing E. coli with concentrations ranging from 10-50 mg/ml and a mean of 30 mg/ml. Garlic extract produce a synergistic effect with all tested antibiotics against all tested ESBL producing E. coli isolates. A Significant decrease in ESBLs genes expression (SHV, TEM and CTX-m) was reported after treatment with Garlic extract (P value: ˂0.001).
 Conclusion: The combinations of antibiotics and Garlic may be more useful than individual agents, so we recommended that further researches should be undertaken to evaluate the combination of Garlic with antibiotics towards ESBL producing E. coli.

Biological synergy of greener gold nanoparticles by using Coleus aromaticus leaf extract

Greener nanotechnology plays an important role in developing alternative and effective treatment strategies for various diseases. Biological synthesis of metal nanoparticles (MNPs) has known to possess suitable alternatives than the existing chemical methods. Greener synthesis of MNPs by using plant extracts has become an emerging field due to their safe, eco-friendly and non-toxic nature that are suitable for synergistic biological activities. Hence, the greener method is chosen by the present study. In the present study, the greener synthesis of gold nanoparticles (AuNPs) was successfully done by using Coleus aromaticus leaf extract at three different temperatures (30 °C, 60 °C and 100 °C). The formation of AuNPs was initially monitored by visual observation and then characterized with the help of diverse techniques like UV–Vis spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), High Resolution-Transmission Electron Microscopy (HR-TEM) and dynamic light scattering (DLS). Surface plasmon resonance (SPR) peak and crystalline nature of AuNPs were obtained by UV–Vis and XRD spectroscopies respectively. FT-IR analysis shows the different characteristic functional groups in turn responsible for the bio-reduction of gold ions by using leaf extract. The formations of different nano-sized AuNPs with their different morphologies were observed by SEM and HR-TEM analyses. Surface charge and stability of the AuNPs were measured by zeta potential and DLS respectively. The synthesized AuNPs coated with cotton fabric was analyzed by UV-Diffuse Reflectance Spectroscopy (UV-DRS), which revealed excellent UV protection against UV radiation. The AuNPs coated cotton fabric exhibited remarkable antibacterial sensitivity against Staphylococcus epidermidis and Escherichia coli. Further, the synthesized AuNPs showed significant cytotoxicity against human liver cancer (HepG2) cell line. The findings of this study revealed that, AuNPs synthesized using Coleus aromaticus leaf extract could be an alternative, safe, and effective source of UV protection, antibacterial and anticancer agents.