scholarly journals Effects of Different TiO2 Nanoparticles Concentrations on the Physical and Antibacterial Activities of Chitosan-Based Coating Film

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1365 ◽  
Author(s):  
Yage Xing ◽  
Xuanlin Li ◽  
Xunlian Guo ◽  
Wenxiu Li ◽  
Jianwen Chen ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Tio2 Nanoparticles ◽  
Fruits And Vegetables ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Inhibitory Effect ◽  
Coating Film ◽  
Coating Films ◽  
Tio2 Nps ◽  
Chitosan Matrix

In this investigation, the effect of different concentrations of titanium dioxide (TiO2) nanoparticles (NPs) on the structure and antimicrobial activity of chitosan-based coating films was examined. Analysis using scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed that the modified TiO2 NPs were successfully dispersed into the chitosan matrix, and that the roughness of the chitosan-TiO2 nanocomposites were significantly reduced. Moreover, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses indicated that the chitosan interacted with TiO2 NPs and possessed good compatibility, while a thermogravimetric analysis (TGA) of the thermal properties showed that the chitosan-TiO2 nanocomposites with 0.05% TiO2 NPs concentration had the best thermal stability. The chitosan-TiO2 nanocomposite exhibited an inhibitory effect on the growth of Escherichia coli and Staphylococcus aureus. This antimicrobial activity of the chitosan-TiO2 nanocomposites had an inhibition zone ranging from 9.86 ± 0.90 to 13.55 ± 0.35 (mm). These results, therefore, indicate that chitosan-based coating films incorporated with TiO2 NPs might become a potential packaging system for prolonging the shelf-life of fruits and vegetables.

scholarly journals Good Bugs vs Bad Bugs: Evaluation of Inhibitory Effect of Selected Probiotics against Enterococcus faecalis

2017 ◽  
Vol 18 (4) ◽  
pp. 312-316 ◽  
Author(s):  
Aarti A Bohora ◽  
Sharad R Kokate
Keyword(s):  
Antimicrobial Activity ◽  
Enterococcus Faecalis ◽  
Pathogenic Bacteria ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Strain ◽  
Inhibition Zone ◽  
Inhibitory Effect ◽  
Indicator Strain ◽  
Oral Bacteria ◽  
Diffusion Method

ABSTRACT Introduction The main goal of endodontics is the prevention of apical periodontitis. This is due to the presence of persistent pathogenic microorganisms, such as Enterococcus faecalis, and its ability to directly cause acute and chronic inflammation in the periapical tissues. Lactobacillus has been shown to promote health in the intestines as well as to inhibit the growth of certain problematic oral bacteria. This study explores shifting the established paradigm of endodontic treatment, which has focused on eliminating all bacteria from the canal system and on elimination of the problematic bacteria through introducing probiotics. A preliminary work was performed to evaluate the possible effectiveness of probiotics in preventing the growth of E. faecalis. Materials and methods Two probiotic cultures Lactobacillus plantarum ATCC 8041 and Lactobacillus rhamnosus ATCC 7408 were selected to check their antimicrobial activity against E. faecalis ATCC 29212 by two methods: agar cup/well diffusion method and deferred antagonism test. Agar cup method A total of 0.5 mL of requisite test pathogen culture was inoculated into 20 mL of molten sterile Mueller and Hinton agar and cooled to 45 ± 2°C. Circular wells of diameter 10 mm were punched in each of the poured plates. Appropriately diluted test samples were added to the above-punched wells. The plates were incubated upright position at 37°C for 24 hours in aerobic conditions. Postincubation, zone of inhibition was measured. The cell-free supernatant of Lactobacillus species was also evaluated for antimicrobial activity. Deferred antagonism test The test probiotic strain was standardized to 0.1 optical density (OD) at 600 nm and inoculated in a 1 cm wide diametric streak across the surface of trypticase soy agar + yeast extract + calcium carbonate (TSYCa) agar using a sterile cotton swab. Then, the plate agar containing the test strain was incubated at 37°C for 24 hours under aerophilic condition and then standardized to 0.1 OD at 600 nm for overnight (18 hours, 37°C). A purified culture of indicator strain (pathogen) was streaked at right angles to the line of original producer growth. Postincubation plates were observed for the inhibition zone width of the indicator strain. Results Under the conditions of this study, Lactobacilli had an inhibitory effect on the growth of E. faecalis by agar cup method but not by deferred antagonism test. Conclusion This pilot study demonstrated that probiotics show a potential in root canal therapy. Clinical Significance If probioitcs are effective against endodontic pathogens, they can be potentially used as intracanal medicaments. This will be a novel concept of introducing bacteriotherapy in endodontics and replacing pathogenic bacteria by healthy bacteria, normal flora. How to cite this article Bohora AA, Kokate SR. Good Bugs vs Bad Bugs: Evaluation of Inhibitory Effect of Selected Probiotics against Enterococcus faecalis. J Contemp Dent Pract 2017;18(4):312-316.

scholarly journals Estimation of antimicrobial activity of green mango ( mangifera indica L. ) Extract on the Growth of Bacteria

2018 ◽  
Vol 29 (1) ◽  
pp. 75
Author(s):  
Hiba Thamir Hussain
Keyword(s):  
Antimicrobial Activity ◽  
Mangifera Indica ◽  
Chemical Properties ◽  
Inhibition Zone ◽  
Inhibitory Effect ◽  
Biological Properties ◽  
Diffusion Method ◽  
Zone Of Inhibition ◽  
Similar Chemical ◽  
Infusion Method

 Abstract:-        Alternative herbal medicine has been used to treat various infections in human as well as in animal, natural plants contain phytoconstituent having similar chemical properties as of synthetic antibiotics ,due to that, the aim of this study was to investigte the biological properties of green mango (mangifera indica L.). The extraction of active phytoconstituent  of green mango was done by infusion method . Antimicrobial activity was carried out by agar well diffusion  method against two species of gram positive bacteria and five gram negative bacteria, at different concentrations 5%,10%,50% . The extract of concentration 5% has showed >2 mm zone of inhibition and after further screene can be considered as minimum inhibitory concentration (MIC) .    The mean zone of inhibition produced inhibition area range between 5mm  and 26 mm .The inhibition zone of  26 mm for  streptococcus has  showed  the   highest  zone of inhibition area. The infusion extract of green mango (mangifera indica L.) showed good inhibitory effect against almost the tested strains .      Green mango extract can serve as a potential  antimicrobial agent  for use in the  food industry and pharmaceutical manufacturing.

scholarly journals Production, Characterization, and Antimicrobial Activity of Mycocin Produced byDebaryomyces hanseniiDSMZ70238

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Safaa A. S. Al-Qaysi ◽  
Halah Al-Haideri ◽  
Zaid Akram Thabit ◽  
Wijdan Hameed Abd Al-Razzaq Al-Kubaisy ◽  
Jamal Abd Al-Rahman Ibrahim
Keyword(s):  
Antimicrobial Activity ◽  
Trichophyton Rubrum ◽  
Killer Toxin ◽  
Pathogenic Fungi ◽  
Inhibition Zone ◽  
Toxin Production ◽  
Inhibitory Effect ◽  
Curvularia Lunata ◽  
Nacl Concentration ◽  
Inhibition Zones

The present study was conducted to estimate the antimicrobial activity and the potential biological control of the killer toxin produced byD. hanseniiDSMZ70238 against several pathogenic microorganisms. In this study, the effects of NaCl, pH, and temperature, killer toxin production, and antimicrobial activity were studied. The results showed that the optimum inhibitory effect of killer toxin was at 8% NaCl, and the diameters of clear zones were 20, 22, 22, 21, 14, and 13 mm forStaphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pyogenes, Candida albicans,andCandida neoformans, respectively. The largest inhibition zones were observed at pH 4.5 with inhibition zone of 16, 18, 17, 18, 11, and 12 mm for the same microorganisms. The results also showed that 25°C is the optimal temperature for toxin killing activity against all targeted microorganisms. In addition, the activity of killer toxin significantly inhibited the growth of fungal mycelia for all target pathogenic fungi and the percentages of inhibition were 47.77, 48.88, 52.22, and 61.11% forTrichophyton rubrum, Alternaria alternata, Trichophyton concentricum,andCurvularia lunata, respectively. The results showed the highest growth rate ofD. hanseniiDSMZ70238 under condition of 8% NaCl concentration, pH 4.5, and 25°C for 72 h.

scholarly journals In Vitro Antimicrobial, Antiviral and Cytotoxicity Activities of Aspergillus oryzae Isolated From El-Baida Marsh in Algeria

2020 ◽  
Vol 10 (4) ◽  
pp. 191-195
Author(s):  
Nacef Houda Sara ◽  
Belhattab Rachid ◽  
Galvez Julio ◽  
Rodriguez-Sojo María Jesus ◽  
Vezza Teresa
Keyword(s):  
Antimicrobial Activity ◽  
Antiviral Activity ◽  
Aspergillus Oryzae ◽  
Antimicrobial Property ◽  
Inhibition Zone ◽  
Inhibitory Effect ◽  
Host Cells ◽  
Minimal Inhibitory Concentrations ◽  
Cytotoxicity Activity

This work covers the study of antimicrobial and antiviral activities of the Aspergillus oryzae strain isolated from saline soil (El-Baida marsh in Algeria). The crude extract obtained with ethyl acetate displayed antimicrobial activity against Gram-positive and Gram-negative bacteria and the yeast Candida albicans with a mean of 16.69 mm of inhibition zone and a minimal inhibitory concentrations MICs between 7.28 and 21.85 μgmL-1. We also assessed the antiviral activity against Herpes simplex-2 Virus (HSV-2), in which no inhibitory effect was exhibited. In addition, cytotoxicity activity was tested in Caco-2 and RAW 264, a human epithelial and a murine macrophage cell line, respectively, revealing a no-toxic effect of the extract. The studied isolate extract possesses an antimicrobial property and its non-toxicity to the host cells becomes very important, and can be exploited for the production of new pharmacological and biotechnological agents.        Keywords: Aspergillus oryzae, antimicrobial activity, antiviral activity, cytotoxicity, fungal extraction.

scholarly journals Biosynthesis of Zinc Oxide (ZnO) Using Culture Biomass of Aspergillus Niger : The Influence of pH On Textile Morphology And Antimicrobial Activity

2021 ◽  
Author(s):  
Yetria Rilda ◽  
Rifki Rinaldi ◽  
Syukri Syukri ◽  
Armaini Armaini ◽  
Refinel Refinel ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Zinc Oxide ◽  
Aspergillus Niger ◽  
Sol Gel ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Hydroxyl Groups ◽  
Cell Biomass ◽  
A Value ◽  
Size And Morphology

Abstract The biosynthesis of zinc oxide (ZnO) is performed through enzymatic mechanisms, by controlling the particle size and morphology of the compound using the sol-gel method. Furthermore, this method utilizes stabilizer obtained from the cell biomass of Aspergillus niger bacteria, in order to yield homogeneous and consistent products, which corresponds with the XRD outcome that exhibits good crystallinity. The evaluation of functional, morphological, and antibacterial activities was carried out at pH 6.0-13.0, as the prepared samples were characterized by FT-IR. The analysis showed the interaction of hydroxyl groups, aromatic rings, as well as N-H and O-Zn-O compounds at a wavenumber of 401-584 cm−1. The XRD and SEM characterizations showed that the structure and crystal phase of ZnO were hexagonal wurtzite at dimensions of 36.2 - 45.4 nm. The differences in pH also influenced the dimensions, morphology, and antimicrobial activity. ZnO with pH of 8.0 was characterized by FESEM-EDAX, based on the analysis of morphological uniformity. This characterization obtained rod and cube structures, with atomic ratios of Zn = 61.5% and O = 38.5%. The UV-DRS spectrum showed that the optical band gap was not significantly influenced by the pH of the reactant solution, with a value of Eg = 3.00–3.11 eV. The differences in morphology further distinguished anti-bacterial properties on textile fibres, through the use of the Gram-negative and positive bacteria (Pseudomonas aeruginosa and Staphylococcus aureus), with inhibition zones of 17-21 mm and 21-25 mm, respectively. Therefore, ZnO is classified as a very strong antibacterial material compared to amoxicillin, with an inhibition zone of 13.6 mm.

scholarly journals Biosynthesis of Zinc Oxide (ZnO) Using Culture Biomass of Aspergillus Niger :The Influence of pH On Textile Morphology And Antimicrobial Activity

2021 ◽  
Author(s):  
Yetria Rilda ◽  
Rifki Rinaldi ◽  
Syukri Syukri ◽  
Armaini Armaini ◽  
Refinel Refinel ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Zinc Oxide ◽  
Aspergillus Niger ◽  
Sol Gel ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Hydroxyl Groups ◽  
Cell Biomass ◽  
A Value ◽  
Size And Morphology

Abstract The biosynthesis of zinc oxide (ZnO) is performed through enzymatic mechanisms, by controlling the particle size and morphology of the compound using the sol-gel method. Furthermore, this method utilizes stabilizer obtained from the cell biomass of Aspergillus niger bacteria, in order to yield homogeneous and consistent products, which corresponds with the XRD outcome that exhibits good crystallinity. The evaluation of functional, morphological, and antibacterial activities was carried out at pH 6.0-13.0, as the prepared samples were characterized by FT-IR. The analysis showed the interaction of hydroxyl groups, aromatic rings, as well as N-H and O-Zn-O compounds at a wavenumber of 401-584 cm−1. The XRD and SEM characterizations showed that the structure and crystal phase of ZnO were hexagonal wurtzite at dimensions of 36.2 - 45.4 nm. The differences in pH also influenced the dimensions, morphology, and antimicrobial activity. ZnO with pH of 8.0 was characterized by FESEM-EDAX, based on the analysis of morphological uniformity. This characterization obtained rod and cube structures, with atomic ratios of Zn = 61.5% and O = 38.5%. The UV-DRS spectrum showed that the optical band gap was not significantly influenced by the pH of the reactant solution, with a value of Eg = 3.00–3.11 eV. The differences in morphology further distinguished anti-bacterial properties on textile fibres, through the use of the Gram-negative and positive bacteria (Pseudomonas aeruginosa and Staphylococcus aureus), with inhibition zones of 17-21 mm and 21-25 mm, respectively. Therefore, ZnO is classified as a very strong antibacterial material compared to amoxicillin, with an inhibition zone of 13.6 mm.

scholarly journals Biosynthesis of TiO2 nanoparticles using prodigiosin and evaluating its antibacterial activity against biofilm producing MDR- Acinetobacter baumannii

2020 ◽  
Vol 13 (2) ◽  
pp. 137-151
Author(s):  
Dalia Ahmed ◽  
Laith Yaaqoob ◽  
Sehand Arif
Keyword(s):  
Antimicrobial Activity ◽  
Atomic Force Microscopy ◽  
Antibacterial Activity ◽  
16S Rrna ◽  
Tio2 Nanoparticles ◽  
Titanium Dioxide Nanoparticles ◽  
Drug Resistant ◽  
Tio2 Nps ◽  
Force Microscopy ◽  
Atomic Force

A rising number of hospital infections were caused by multi drug resistant A.baumannii. This microorganism has become a big global concern for clinicians. This study aimed to evaluate the antimicrobial activity of biosynthesized TiO2 nanoparticles against biofilm producing multi drug resistant A. baumannii. Bacteria were isolated from burn wounds. The selected isolate was identified using the routine biochemical assays, viteck 2, and confirmed by PCR technique, targeting the 16S rRNA and blaOXA-51 genes. Antimicrobial susceptibility tests were performed using Viteck 2 system and the biofilm production was tested by using microtiter plate method. S marcescens was used for production of the prodigiosin which characterized later by UV-visible spectroscopy and then was used for biosynthesis of titanium dioxide nanoparticles (TiO2) NPs. Atomic force microscopy, X-ray diffractometer and field emission scanning electron microscopy were used for characterization of TiO2 NPs. Antimicrobial activity of TiO2 NPs was examined by well diffusion assay using concentration of 0.4- 0.006 mg/ml. The studied isolate was beta-lactamase producer and showed resistance to aminoglycosides, quinolones, furanes and trimethoprim/ sulphonamide, PCR amplification of 16S rRNA and blaOXA-51 genes was used for detection of A baumannii. The selected isolate was a strong biofilm producer with 5.9 times more than the OD values of the control. Atomic force microscopy images showed that the synthesized TiO2 NPs were in spherical shape with an average diameter of 67.49 nm. The TiO2 NPs inhibited the bacterial growth at concentrations of ≥ 0.1mg/ ml and a maximum zone of inhibition recorded was 22 mm at concentration of 0.4 mg/ ml. Biosynthesis of TiO2 NPs using prodigiosin was showed a promising antibacterial activity against strong biofilm producing MDR- A. baumannii.

scholarly journals Evaluation of Antimicrobial Activity of Several Medicinal Plants Against Clinically Isolated Staphylococcus Aureus from Humans and Sheep

2021 ◽  
Vol In Press (In Press) ◽  
Author(s):  
Bahman Fazeli-Nasab ◽  
Laleh Shahraki-Mojahed ◽  
Gelareh Sohail-beygi ◽  
Mehrangiz Ghafari
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Activity ◽  
Ethanolic Extract ◽  
Inhibition Zone ◽  
Inhibitory Effect ◽  
Thymus Vulgaris ◽  
Taxus Baccata ◽  
Growth Inhibition Zone ◽  
Hypericum Perforatum L ◽  
The University

Background: Continuous and indiscriminate use of chemical drugs causes an important phenomenon of resistance to microorganisms. Accordingly, the effect of medications is minimized or offset, increasing drug use and the need to study mixtures with more latest and powerful formulations. On the other hand, it has been reported that many plants essential oils have a significant inhibitory effect on pathogenic microorganisms. Objectives: This study aimed to evaluate the antimicrobial activity of some curative herbs against some clinical bacteria of humans and sheep. Methods: The leaves of chicory (Cichorium intybus L.), Hypericum perforatum L., Lavandula angustifolia, Thymus vulgaris L., and Taxus baccata L. were collected and determined in the botanical laboratory of the University of Zabol. Forty grams of dried leaves was used in 400 mL of ethanol (96%) to prepare the ethanolic extract. DPPH was used to determine the activity of reactive oxygen species (ROS) trapping. The antimicrobial effects were studied by the disk diffusion (6 mm) method in Müller-Hinton agar medium according to the method by Bauer et al. Results: The minimum inhibitory concentrations (MICs) of chicory, thyme, H. perforatum, French lavender, and yarrow extracts in human clinical Staphylococcus aureus were 6.25, 12.5, 3.1, 25, and 6.25 ppm, respectively, but, in sheep, clinical S. aureus, were 12.5, 6.25, 3.1, 12.5, and 25 ppm, respectively. The minimum bactericidal concentrations (MBCs) of chicory, thyme, H. perforatum, French lavender, and yarrow extracts in human clinical S. aureus were 12.5, 25, 6.25, 50, and 12.5 ppm, respectively, but, in sheep clinical S. aureus, were 25, 12.5, 6.25, 25, and 50 ppm, respectively. The most effective extract in inhibiting the growth of S. aureus was the H. perforatum L. extract with an 8.9-mm diameter growth inhibition zone. Conclusions: Regarding the side effects of artificial medications and antimicrobials, as well as the significant influence of healing herb extracts used in this study, it was found that H. perforatum was the most effective plant against S. aureus. It should be noted that plant extracts were more effective in human clinical S. aureus than in sheep clinical S. aureus.

scholarly journals In vitro antimicrobial activity of aqueous extracts from Lentinula edodes isolates against Colletotrichum sublineolum and Xanthomonas axonopodis pv. Passiflorae

2015 ◽  
Vol 41 (1) ◽  
pp. 13-20 ◽  
Author(s):  
Nivea Maria Tonucci-Zanardo ◽  
Sérgio Florentino Pascholati ◽  
Robson Marcelo Di Piero
Keyword(s):  
Antimicrobial Activity ◽  
Lentinula Edodes ◽  
Anion Exchange Chromatography ◽  
Antibacterial Activities ◽  
Inhibitory Effect ◽  
Exchange Chromatography ◽  
Causal Agent ◽  
Aqueous Extracts ◽  
Colletotrichum Sublineolum

The aim of this study was to evaluate the antimicrobial activity of aqueous extracts from fruiting bodies of different isolates of Lentinula edodeson the pathogens Colletotrichum sublineolum, the causal agent of anthracnose in sorghum, and Xanthomonas axonopodispv. passiflorae, the causal agent of bacterial spot in passion fruit. Results showed that the aqueous extracts from isolates LE JAB-K and LE 95/01 significantly reduced C. sublineolumspore germination,while the isolate LE 96/22 was the only one to inhibit the pathogen mycelial growth. However, all L. edodesisolates showed inhibitory effect on C. sublineolumappressorium formation. Regarding X. axonopodispv. passiflorae, the aqueous extracts from all L. edodesisolates significantly reduced the in vitromultiplication of the bacterium. However, antimicrobial activity was lost when the extracts were autoclaved, demonstrating their thermolabile property. The aqueous extract from isolate LE 96/22 was also partially purified by anion exchange chromatography and fraction V exhibited high inhibitory activity on the in vitromycelial growth of C. sublineolum, while the multiplication of X. axonopodispv. passifloraewas inhibited by fractions IV, V and VII. Thus, L. edodesisolates were shown to produce compounds exhibiting antifungal and antibacterial activities against phytopathogens, which are mainly concentrated in fraction V.

scholarly journals Honey: Determination of volatile compounds, antioxidant and antibacterial activities

2021 ◽  
Vol 39 (No. 3) ◽  
pp. 208-216
Author(s):  
Semiramis Karlidag ◽  
Merve Keskin ◽  
Sinan Bayram ◽  
Nazlı Mayda ◽  
Asli Ozkok
Keyword(s):  
Volatile Compounds ◽  
Total Phenolic Content ◽  
Pathogenic Bacteria ◽  
Phenolic Content ◽  
Inhibition Zone ◽  
Antibacterial Activities ◽  
Inhibitory Effect ◽  
Total Phenolic ◽  
Aliphatic Acid ◽  
Health And Nutrition

Honey is an important functional food for human health and nutrition that is collected by honey bees and stored in the honeycombs. In this study, total phenolic content, antioxidant activity and volatile compounds of 13 different honey samples collected from various districts of Malatya province were investigated. As a result of this study, it was determined that the total phenolic content varied between 8.50 mg GAE 100 g<sup>–1</sup> and 73.90 mg GAE 100 g<sup>–1 </sup>and it was observed that the honey samples were rich in aldehydes, aliphatic acid and esters, alcohols, hydrocarbons, carboxylic acid esters, ketones, terpenes, fatty acids and esters. In addition, the antibacterial effects of honey samples were determined against 18 different pathogenic bacteria using agar well diffusion (AWD) method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In AWD assay, it was recorded that inhibition zone diameters varied between 9 mm and 14 mm and honey samples were found to have a partial inhibitory effect against selected target pathogens.

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