11 research outputs found
Photocatalytic decolorization of bromothymol blue using biogenic selenium nanoparticles synthesized by terrestrial actinomycete Streptomyces griseobrunneus strain FSHH12
The aim of the present study was to isolate and identify a terrestrial actinomycete bacterial
strain capable to produce selenium nanoparticles (Se NPs) followed by purification of the
biogenic Se NPs and evaluation of their photocatalytic degradation compared to selenium
dioxide. Among 30 actinomycete bacterial strains obtained from environmental soil samples,
one isolate (identified as Streptomyces griseobrunneus strain FSHH12 based on the 16S rDNA
gene sequence analysis) was selected and used for production of Se NPs. The biologically
synthesized Se NPs was consequently purified by an organic–aqueous partitioning system
and characterized using scanning electron microscopy, transmission electron microscopy,
energy dispersive X-ray, UV–visible spectroscopy, Fourier transform infrared spectroscopy,
and X-ray diffraction spectroscopy. The obtained results of photocatalytic degradation of
bromothymol blue using the purified Se NPs (64 μg/mL) revealed 62.3% of dye removal
under UV illumination (15 W) after 60 min incubation of dye solution
Bioassay Screening of the Essential Oil and Various Extracts of Fruits of Heracleum persicum Desf. and Rhizomes of Zingiber officinale Rosc. using Brine Shrimp Cytotoxicity Assay
In the present work, the bioassay screening of the essential oil and various extracts of two plants including fruits of Heracleum persicum Desf. and rhizomes of Zingiber officinale Rosc. have been studied with brine shrimp test. There is only one report about cytotoxicity of H. sphondylium in literature and so H. persicum has been used as second selection. At first essentials oil and various extracts of two plants including petroleum ether, chloroform, methanol, ether and aqueous were provided. Then, different concentrations of them were prepared. These fractions were evaluated for toxicity using Brine Shrimp Lethality assay (BSL). Each of fractions was assessed by two methods of disk and solution. Survivors were counted after 24 h. These data were processed in Probit-analysis program to estimate LC50 values (the concentration at which 50% lethality was observed) with 95% confidence intervals for statistically significant comparisons of potencies. In disc method, methanol extract of Z. officinale (LC50=28.3134 μg/ml) showed the most activity in comparison with positive standard of potassium dichromate (LC50=23.2893 μg/ml); but in solution method, essential oil of H. persicum ( LC50=0.0071 μl/ml) was the most active fraction in comparison with potassium dichromate (LC50=27.7528 μg/ml). Totally, among tested fractions, essential oil of the H. persicum has been exhibited the most cytotoxicity. The essential oil of H. persicum was analyzed by GC-MS. The major constituents were hexyl butyrate and octyl acetate
A study on effects of leadership style on innovation: A case study from automaker industry
Leadership is one of the most important components of management in any business unit. An organization with good leadership tends to have a better chance to survive in todays’ competitive environment. This paper considers the effects of leadership style on innovation in one of the biggest automakers in Iran named Iran Khodro. The proposed study of this paper designs a questionnaire and distributes it among a sample of 278 regular employees and 61 middle level managers of this firm. The results of the survey indicate that there is a meaningful difference between leadership style and standard leadership style among middle level managers when the level of significance is five percent. In addition, there is a meaningful difference between innovation and its components with standards among regular employees. Finally, leadership has positive and meaningful impact on employees’ innovation
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 ACTIVITY OF BACILLUS SP. STRAIN FAS1 ISOLATED FROM SOIL
During screening for antibiotic producing microorganisms from environmental soil samples, the supernatant of
a bacterial isolate was found to have antibacterial and antifungal activity on the standard indicator species. The
standard cylinder-plate method was used to determine the inhibitory effect of the crude supernatant of each
isolate on 6 bacterial and 3 fungal standard strains by measuring the diameter of inhibition zone. The highest
inhibition zone on Aspergillus niger belonged to culture broth of isolate FAS1 by 25 mm, and this isolate was
the most efficient microorganism to inhibit standard bacterial and fungal species. Based on morphological and
biochemical properties as well as 16S rDNA gene analysis, the selected isolate (isolate FAS1) belonged to
Bacillus genus. Investigation on the ability of different culture media for antibiotic production led to select
Luria-Bertani media for further studies. Treatment of the culture broth of the isolate FAS1 using typical protease
didn’t decrease the antimicrobial activity of the supernatant. After extracting of culture broth of the selected
isolate by ethyl acetate as an organic solvent, the inhibitory effect was mainly increased. More investigation was
done by bioautography method where the ethyl acetate fraction of the broth culture was separated on TLC by
chloroform:methanol, 60:40 as mobile phase and Rf were calculated for inhibition spots
Preparation and evaluation of the effect of Fe3O4@piroctone olamine magnetic nanoparticles on matrix metalloproteinase-2: A preliminary in vitro study
In the present study, Fe3O4 magnetic nanoparticles were
synthesized by the coprecipitation of Fe2+ and Fe3+ ions and
used as a nanocarrier for the production of piroctoneolamine-
loaded Fe3O4 nanoparticles (Fe3O4@PO NPs). The
nanocrystalline structure of the prepared iron oxide species
was confirmed by the X-ray diffraction spectroscopy method.
Particle size distribution analysis showed that the size of
Fe3O4@PO NPs was in the range of 5–55 nm. The
magnetization curve of Fe3O4@PO NPs (with saturation
magnetization of 28.2 emu/g) confirmed its ferromagnetic
property. Loading of PO on the surface of Fe3O4 NPs
qualitatively verified by Fourier transform infrared spectrum
obtained from Fe3O4@PO NPs. Cytotoxicity studies on the
human fibrosarcoma cell line (HT-1080) revealed higher
inhibitory effect of Fe3O4@PO NPs (50% cell death [IC50] of
8.1 μg/mL) as compared with Fe3O4 NPs (IC50 of 117.1 μg/mL)
and PO (IC50 of 71.2 μg/mL) alone. In the case of human
normal fibroblast (Hs68), the viability percentage was found to
be 75% in the presence of Fe3O4@PO NPs (120 μg/mL). Gelatin
zymography showed 17.2% and 34.6% inhibition of matrix
metalloproteinase-2 (MMP-2) in the presence of Fe3O4@PO
and PO, respectively, at the same concentration of 40 μg/mL,
whereas Fe3O4 NPs did not inhibit MMP-2 at any
concentration. C� 2014 International Union of Biochemistry and
Molecular Biology, Inc. Volume 61, Number 6, Pages 676–682, 201
BIOASSAY SCREENING OF THE ESSENTIAL OIL AND VARIOUS EXTRACTS FROM 4 SPICES MEDICINAL PLANTS
Four commonly used spices plants in Iran were evaluated for cytotoxicity effect using Brine Shrimp Lethality
(BSL) assay. Essential oils and various extracts of Heracleum persicum, Nigella arvensis, Cinnamomum
zeylanicum and Zingiber officinale were assessed by two methods of disk and solution of BSL. Data were
processed in probit-analysis program to estimate LC50 values. All of the tested fractions have exhibited more
cytotoxicity in the solution method. Essential oils of H. persicum and C. zeylanicum have shown the most
cytotoxicity with LC50 values 0.007 and 0.03 μg/ml respectively. None of aqueous extracts showed significant
cytotoxicity. The analysis of the essential oil of H. persicum showed the hexyl butyrate and octyl acetate as the
main compounds. These results suggest some limitation for using of these spices in diet. Furthermore, these
plants could be considered as a source of cytotoxic compounds which might be studied in more details
One-pot, four-component synthesis of novel cytotoxic agents 1-(5-aryl-1,3,4-oxadiazol-2-yl)-1-(1H-pyrrol-2-yl)methanamines
A series of N-benzyl-1-(5-aryl-1,3,4-oxadiazol-2-yl)-1-(1H-pyrrol-2-yl)methanamines were synthesized
via one-pot reaction of appropriate benzylamine, pyrrole-2-carbaldehyde, (N-isocyanimino)triphenylphosphorane,
and a carboxylic acid. The anti-tumor potential of title compounds was tested against
several cancer cell lines by using MTT assay. Some tested compounds including 5e, 5p and 5q exhibited
comparable or better cytotoxic activity against A549, HT29 or HT1080 cells in comparison to the reference
drug doxorubicin. Also, the cytotoxic activity of compounds 5d and 5n against MCF-7 was better
than that of doxorubicin. Compound 5n with IC50 value of 4.3 mM was 4-fold more potent than doxorubicin.
The structureeactivity relationship study revealed that the introduction of halogen atoms on
both 5-phenyl ring and N-benzyl part improved the cytotoxic activity against all tested cell lines