20 research outputs found
Partial Purification and Characterization of a Thermoalkalophilic Lipase Originated from Bacillus atrophaeus FSHM2 and its Application for Ester Synthesis
A thermoalkalophilic lipase producing bacterial strain, identified as
Bacillus atrophaeus FSHM2 using 16S rDNA sequencing analysis was isolated
from salty soil and its lipase was partially purified and characterized. The obtained
results revealed that glucose, hazelnut oil, urea and calcium ion positively affected
the lipase production by increasing the lipolytic activity to 13582.5, 6270, 4442 and
5505 U LG1, respectively compared to that of basal medium (4150 U LG1). The
partially purified lipase acted optimally at pH 9 and retained 88.2% of its initial
activity after 1 h of incubation at 100°C. A two fold increase in the relative activity
of the partially purified lipase was obtained in the presence of 4 M of NaCl.
Application of the partially purified lipase for the synthesis of ethyl and methyl
valerate in the organic solvent medium (xylene) resulted in 81.6 and 62.4%
esterification, respectively, after 24 h of incubation
Antimicrobial and anti-biofilm activities of Bi subnitrate and BiNPs produced by Delftia sp. SFG against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa, and Proteus mirabilis
Cytotoxic and antioxidant activity of the biogenic bismuth nanoparticles produced by Delftia sp. SFG
Antimicrobial, anti-biofilm, and anti-proliferative activities of lipopeptide biosurfactant produced by Acinetobacter junii B6
Lipopeptide biosurfactants (LPBs) are amphiphilic compounds produced by microorganisms exhibiting various biological activities. The main aim of the present study was to assess the in vitro antimicrobial, anti-biofilm, and cytotoxic effects of LPB produced by Acinetobacter junii (AjL). We determined AjL minimum inhibitory concentration (MIC) against both Gram-positive and Gram-negative bacteria as well as two fungal strains. Also, the anti-biofilm activity of AjL against the biofilm produced by clinically isolated bacterial strains was investigated. The AjL non-selectively showed activity against both Gram-positive and Gram-negative bacterial strains. The obtained results of the present study exhibited that the AjL in concentrations nearly below critical micelle concentration (CMC) has an effective antibacterial activity. It was found that the MIC values of AjL were lower than standard antifungal and it exhibited nearly 100 inhibition against Candida utilis. The attained results of the biofilm formation revealed that AjL disrupted the biofilm of Proteus mirabilis, Staphylococcus aureus, and Pseudomonas aeruginosa at 1250 ĂÂŒg/ml and 2500 ĂÂŒg/ml concentrations. The attained results of cytotoxic effect (determined by WST-1 assay) of the AjL revealed IC50 of 7.8 ñ 0.4 mg/ml, 2.4 ñ 0.5 mg/ml, and 5.7 ñ 0.1 mg/ml, against U87, KB, and HUVEC cell lines, respectively. The results indicated that AjL has a potential application in the relatively new field of biomedicine. Ă© 2019 Elsevier Lt
Rapid and Facile Microwave-Assisted Synthesis of Palladium Nanoparticles and Evaluation of Their Antioxidant Properties and Cytotoxic Effects Against Fibroblast-Like (HSkMC) and Human Lung Carcinoma (A549) Cell Lines
We report here a simple microwave irradiation method (850 W, 3 min) for the synthesis of palladium nanoparticles (Pd NPs) using ascorbic acid (as reducing agent) and sodium alginate (as stabilizer agent). The synthesized nanoparticles were characterized using transmission electron microscopy (TEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), UV-Visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR) techniques. Antioxidant properties and cytotoxic effects of as-synthesized Pd NPs and Pd (II) acetate were also assessed. UV-Vis study showed the formation of Pd NPs with maximum absorption at 345 nm. From TEM analysis, it was observed that the Pd NPs had spherical shape with particle size distribution of 13Ăąïżœïżœ33 nm. Based on DPPH radical scavenging activity and reducing power assay, the antioxidant activities of Pd NPs were significantly higher than the Pd (II) acetate (p < 0.05). At the same concentration of 640 ĂÂŒg/mL, the scavenging activities were 32.9 ñ 3.2 (Pd (II) acetate) and 27.2 ñ 2.1 (Pd NPs). For A549 cells treated 48 h with Pd NPs, Pd (II) acetate, and cisplatin, the measured concentration necessary causing 50 cell death (IC50) was 7.2 ñ 1.7 ĂÂŒg/mL, 32.1 ñ 2.1 ĂÂŒg/mL, and 206.2 ñ 3.5 ĂÂŒg/mL, respectively. On HSkMC cells, the IC50 of the Pd NPs (320 ĂÂŒg/mL) was higher compared to Pd (II) acetate (228.7 ñ 3.6 ĂÂŒg/mL), which confirmed lower cytotoxicity of the Pd NPs. Ă© 2019, Springer Science+Business Media, LLC, part of Springer Nature
αâFe2O3@Ag and Fe3O4@Ag CoreâShell Nanoparticles: Green Synthesis, Magnetic Properties and Cytotoxic Performance
Abstract This work provides the synthetic route for the arrangement of Fe3O4@Ag and αâFe2O3@Ag coreâshell nanoparticles (NPs) with cytotoxic capabilities. The production of Fe3O4@Ag and αâFe2O3@Ag coreâshell NPs was facilitated utilizing S. persica bark extracts. The results of Powder Xâray Diffraction (PXRD), Ultravioletâvisible (UVâVis) spectroscopy, Vibrating Sample Magnetometry (VSM), Energy Dispersive Xâray (EDX) analysis, Field Emission Scanning Electron Microscopy (FESEM), and Transmission Electron Microscopy (TEM) supported the green synthesis and characterization of Fe3O4@Ag and αâFe2O3@Ag NPs. The particle size was measured by the TEM analysis to be about 30 and 50â
nm, respectively; while the results of FESEM showed that αâFe2O3@Ag and Fe3O4@Ag particles contained multifaceted particles with a size of 50â60â
nm and 20â25â
nm, respectively. The outcomes of VSM were indicative of a saturation magnetization of 37 and 0.18â
emu/g at room temperature, respectively. The potential cytotoxicity of the synthesized coreâshell nanoparticles towards breast cancer (MCFâ7) and human umbilical vein endothelial (HUVEC) cells was evaluated by an MTT assay. αâFe2O3@Ag NPs were able to destroy 100â% of MCFâ7â
cell at doses above 80â
ÎŒg/mL, and it was confirmed that Fe3O4@Ag NPs at a volume of 160â
ÎŒg/mL can destroy 90â% of MCFâ7â
cells. Thus, the applicability of the prepared nanoparticles of these nanoparticles in biological and medical fields has been demonstrated