Antimicrobial Activity and Mode of Action of Aspergillus terreus Strain (MTCC9618) Mediated Biosynthesized Silver Nanoparticles-AgNPs Against Staphylococcus aureus and Escherichia coli

2021 ◽  
pp. 2150038
Author(s):  
Abaysew Ayele Flifl ◽  
Rita Mujumdar Singh

Fungal approaches bio-synthesis of silver nanoparticles (AgNPs) have been given attention because of their cost effectiveness and environment friendliness. Therefore, fungal Aspergillus terreus (MTCC 9618) intermediated biosynthesis of AgNPs was conducted, and the SEM, EDS and XRD reports confirmed the synthesis of well-organized, structured and stabilized AgNPs. Antimicrobial efficacy of disk diffusion assay of AgNPs (10, 20 and 30[Formula: see text][Formula: see text]g/ml) dosage was confirmed against Staphylococcus aureus and Escherichia coli and found that has bactericidal effects against both strains. Broth assay was also confirmed through LB broth media and colony forming units (CFU) which defined that biosynthesized AgNPs had much potential effect against gram negative ([Formula: see text]ve) than gram positive ([Formula: see text]ve) due to its peptidoglycan thickness. AgNPs had adverse mode of action on both bacterial strains and resulting was found damaged site on cell wall, necrosis, shrinkage, influx out and ruptures of the cells according to SEM scanning profiles. This study promised to green and economical way of AgNPs biosynthesis along with targeted antimicrobial effects in food preservative, biomedical coating tools, fabrics and pharmaceutical industries.

Biosynthesis of silver nanoparticles, especially fungal mediated method is given attention in the development of new drugs for resistance pathogens, molecular diagnosis, drug delivery therapy and in catalytic sensor due to its cost effective, none toxicity and eco-friendly. The present study focused on the fungal mediated biosynthesis of silver nanoparticles using Aspergillus terrues strain (MTCC 9618). The synthesized nanoparticles was monitored by spectrophotometer SEM, XRD and its band gap was determined by Tuac equation. After while the fungal crude cells was exposed to 5mM silver nitrate the reduction reaction was recorded according to red shift colorchange. Based on ultra violet spectrophotometeran absorbance was recorded in a distinct pick around 430nm - 450nm and also the band gab was determined using Tuac equationsuch that 2.08eV, 2.02eV, 2.0eV and 1.96eV at about 10min, 30min, 12h and 24h respectively. The AgNPs coated cotton fabrics was developed through direct exposed to extracellular metabolites and 100ppm colloidal solution of AgNPs. The antimicrobial efficacy of the synthesized AgNPs coted cotton fabrics against gram positive Hospital staphylococcus aureus pathogenstrains was conducted by disk diffusion assay. In which the antimicrobial efficacy of coated cotton-Ag against human pathogens was proofed how the staphylococcus aureus had susceptible too and (16mm) zone of inhibition was recorded. Based on disk diffusion assay at 10ug/mL minimum inhibition concentration (MIC)10.5 mm inhibition zone was noted consequently, this study accomplished that Aspergillus terreus strain mediated biosynthesis of silver nanoparticles is cost effective, time saving, eco-friendly and small spherical (<10nm) had produced against to Physio-chemical means. The bio-synthesized silver nanoparticles cotton fabrics publicized that a higher efficacy of antimicrobial activity against staphylococcus aureus and the result was considerable suggested in widely range used in textile and pharmaceutical industries to enrich durability, strength, quality of products against a clinical pathogens application as well bad odor and spoilage of dusts from fabrics.


2018 ◽  
Vol 21 (0) ◽  
Author(s):  
Flávia Cíntia de Oliveira ◽  
Tamara Rezende Marques ◽  
Gustavo Henrique Andrade Machado ◽  
Thaís Cristina Lima de Carvalho ◽  
Aline Aparecida Caetano ◽  
...  

Abstract The phenolic compounds from various extracts of jabuticaba skin powder (JSP) were characterized in this study, and the antibacterial activity assessed. The phenolic compounds were extracted from the JSP using four methods: a) acetone extraction - 1 g JSP: 10 mL 70% acetone, resting for 2 hours; b) aqueous extract - 1 g JSP: 15 mL water, under agitation; c) ethanolic extract - 1 g JSP: 15 mL acidified ethanol, under agitation; and d) methanolic extract - 1 g JSP: 50 mL 50% methanol, under reflux. The antibacterial activity was evaluated by the agar diffusion assay, using Escherichia coli ATCC 11229, Salmonella choleraesuis ATCC 6539, Pseudomonas aeruginosa ATCC 15442, Staphylococcus aureus ATCC 6538 and Listeria monocytogenes ATCC 19117. The ethanolic and methanolic extracts showed the highest levels of phenolic compounds, especially of cyanidin chloride, catechin and epicatechin. The extracts did not inhibit the growth of Escherichia coli and Salmonella choleraesuis, but inhibited 30% of the growth of Pseudomonas aeruginosa with an extract concentration of 250 µg mL-1. Against Staphylococcus aureus and Listeria monocytogenes the highest inhibitory effect observed was 41.8% for the ethanolic extract, followed by 36% inhibition by the methanolic extract, thus revealing the potential of these extracts as possible alternatives for use in the food and/or pharmaceutical industries.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Shiara Ramdath ◽  
John Mellem ◽  
Londiwe Simphiwe Mbatha

Health issues involving inadequate treatment of diseases such as cancer and microbial infections continue to be the subject of much ongoing recent research. Biosynthesized silver nanoparticles (AgNPs) were characterized using Transmission Electron Microscopy (TEM), Zeta Sizer, Ultraviolet (UV), and Fourier Transform Infrared (FTIR) spectroscopy. Their antimicrobial activity was evaluated on selected Gram-positive and Gram-negative bacterial strains, using the disc diffusion and broth dilution assays. Cell viability profiles were evaluated using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and apoptosis studies on selected human noncancer and cancer cells. The biosynthesized AgNPs were evaluated to be spherical clusters, with sizes between 40 and 70 nm. The absorption peak at 423 nm and the presence of polyphenols confirmed the synthesis and stabilization of these tested AgNPs. The AgNPs showed a good stability of −23.9 ± 1.02 mV. Good antimicrobial activity (6.0–18.0 mm) was seen on all tested bacteria at a minimum inhibitory concentration (MIC) ranging from 5 to 16 μg/ml, with the highest activity seen against Gram-negative Escherichia coli (18 ± 0.5 mm), and the lowest activity was seen against Gram-positive Listeria monocytogenes (6.0 ± 0.4 mm) after treatment with the AgNPs. These NPs showed a concentration-dependent and cell-specific cytotoxicity with low IC50 values (41.7, 56.3, and 63.8 μg/ml). The NPs were well tolerated by tested cells as indicated by a more than 50% cell viability at the high dose tested and low apoptotic indices (<0.2). These findings indicated that these biosynthesized AgNPs showed great potential as effective antibacterial agents and anticancer drug delivery modalities.


2021 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Antonio Carlos Pereira de Menezes Filho ◽  
Matheus Vinícius Abadia Ventura ◽  
Carlos Frederico de Souza Castro

Tibouchina granulosa is a species that blooms annually in several regions of Brazil. This species is still little explored in terms of phytocompounds in all organs of this plant, especially the floral organ. Flowers of T. granulosa were collected in the municipality of Rio Verde, Goiás, Brazil, in 2021. The hydroethanolic floral extract was prepared by maceration and qualitative phytochemical (colorimetric reactions and salt formation) and antibacterial analyzes performed and the results expressed in millimeters of inhibition at different concentrations in mg mL-1. Several phytochemical classes were observed with positive results, especially for alkaloids, phenolics, oxylates, saponins, carbohydrates and tannins. As for the bacterial assay, potential antibacterial activity was observed for all bacterial strains tested, except for Salmonella serovar Thyphymurium and serovar Enteritidis. Expressive inhibitions were observed for Enterococcus faecalis > Pseudomonas aeruginosa > Staphylococcus aureus and Escherichia coli at the highest concentrations between 100-50 mg mL-1. The floral extract of Tibouchina granulosa showed phytotherapeutic potential with the presence of several phytochemical groups and expressive antibacterial activity.


Author(s):  
A. A. Katun ◽  
A. R. Abdulmumin ◽  
M. U. Yahaya ◽  
N. K. Habeeb ◽  
A. Bala

The investigation into soil bacteria has been widely studied and becoming increasingly appreciated as an exceptional reservoir of unique naturally occurring biologically active metabolites with pharmaceutical applications. This article aimed to isolate, identify and biochemically characterize antibiotic-producing bacteria from anthill soils in the permanent site of Ibrahim Badamasi Babangida University, Lapai (IBBUL), Niger State, Nigeria. The sum of ten samples were collected from five sampling sites, the sampling was done in threefold (morning, noon and evening) and analyzed adopting standard microbiological protocols. The obtained result revealed that the total bacteria count in the morning ranges from 2.1×107 cfu/mL to 1.4×106 cfu/mL, noon count ranges from 3.1×107 to 2.6×106 cfu/mL while evening count was in the range of 2.1×107 cfu/mL to 1.7×106 cfu/mL. A total number of five (5) bacteria were isolated as Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, Bacillus lentus and Micrococcus reseus. The total prevalence of the bacterial isolates in the morning, noon and evening were calculated as B. subtilis (109.08%), S. epidermidis (36.36%), M. reseus (36.36%), B. lentus (63.63%), and S. aureus (54.54%) respectively. These isolates were further assayed against Escherichia coli, Salmonella typhi, Klebsiella sp. and Staphylococcus aureus. The antibacterial outcome showed that two (2) (40%) anthill isolates exhibited antibacterial activity against three (3) tested bacteria (Escherichia coli, Salmonella typhi and Staphylococcus aureus). This research study has showcased that the production of inhibitory substances are common among some of the bacterial strains isolated from anthills.


Author(s):  
Haribhai Rabari ◽  
Hetal Vankar ◽  
Beenkumar Prajapati

The emergence of multidrug microbial resistance is the main challenges that the modern scientists have so far been facing in the recent era. In this respect, new series of drug classes having potential to give antimicrobial effect have been synthesized. A new series of 5- substituted-1,10 b-dihydroimidazole[1,2-c]quinazoline derivatives 8a-e have been synthesized and screened for antibacterial activity and antifungal activity. Synthesized derivatives were characterized by IR, MASS and 1H-NMR spectroscopy. Synthesized compounds show good activity, which was comparable to the standard drug and it can be useful for the further clinical study. Antibacterial activity was evaluated against four different pathogenic bacterial strains like Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudo-monas aeruginosa. Among the screened compounds, 8e show good antibacterial activity against Staphylococcus aureus and Escherichia coli with MIC of 50 and 100 μg/ml respectively. Antifungal activity was evaluated  against two strains of fungi. Among the synthesized derivates, compound 8c was emerged out as the potent antifungal compound against Candida albicans and Aspergillus niger with MIC of 25 μg/ml and 75μg/ml respectively. Compound 8e also shows good antifungal activity with MIC of 50 μg/ml against both Candida albicans and Aspergillus niger. The overall results of this study indicated that  synthesized quinazoline derivatives had the potential to act as an antibacterial and antifungal agent, hence further investigation is warranted.


2009 ◽  
Vol 4 (1) ◽  
pp. 1934578X0900400 ◽  
Author(s):  
Branislava Lakušić ◽  
Violeta Slavkovska ◽  
Milica Pavlović ◽  
Marina Milenković ◽  
Jelena Antić Stanković ◽  
...  

The essential oils of the aerial parts and fruits of Chaerophyllum aureum L., collected from two mountains in Serbia, were analyzed by GC and GC/MS. Sabinene (18.5-31.6%), p-cymene (7.9-25.4%) and limonene (1.9-10.9%) were characterized as the main constituents. The oils were tested against six bacterial strains and one strain of yeast, Candida albicans. The highest antimicrobial activity was observed against the Gram-positive bacteria Staphylococcus aureus, S. epidermidis and Micrococcus luteus, while of the Gram-negative strains, Escherichia coli was the most sensitive.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Thi-Diem Bui ◽  
Quang-Liem Nguyen ◽  
Thi-Bich Luong ◽  
Van Thuan Le ◽  
Van-Dat Doan

In this study, Mn-doped ZnSe/ZnS core/shell quantum dots (CSQDs) were synthesized in aqueous solution using polyethylene glycol as a surface stabilizer and successfully applied in the detection of Escherichia coli O157:H7 and methicillin-resistant Staphylococcus aureus (MRSA) for the first time. The CSQDs were conjugated with anti-E. coli antibody and anti-MRSA antibody via protein A supported by 1-ethyl-3-(-3-dimethylaminopropyl)carbodiimide hydrochloride for fluorescent labeling of the intact bacterial cells. The detection was performed for the bacterial strains cultivated in Luria-Bertani liquid medium. The obtained results indicate that E. coli O157:H7 and MRSA can be detected within 30 min at a high sensitivity of 101 CFU/mL. This labeling method based on the highly fluorescent CSQDs may have great potential for use in the food industry to check and prevent outbreaks of foodborne illness.


2014 ◽  
Vol 875-877 ◽  
pp. 87-90 ◽  
Author(s):  
Chutimon Satirapipathkul ◽  
Tanakan Chatdum

The film-forming potential of isolate of seed polysaccharide fromCassia fistulawas investigated. Increasing the glycerol concentration in the film increased elongation at break, film solubility and water vapor permeability but decreased tensile strength (TS). The film impregnated with the acetone extract ofAtractylodes lanceawas assessed for inhibition ofEscherichia coliandStaphylococcus aureus. The obtained results showed that the films exhibited antibacterial activity against both bacterial strains. Disc-diffusion assay revealed that the film resulted in a larger inhibition zone around the film onStaphylococcus aureusthan it did onEscherichia coliat the same extract concentrations (0.1 to 0.9 wt %). It can be seen that the film has satisfactory physical and antibacterial properties.


Author(s):  
Melisa A. Quinteros ◽  
Cano Aristizabal Viviana ◽  
Renné Onnainty ◽  
Verónica S. Mary ◽  
Martín G. Theumer ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document