Abstract: Antifungal activities of ether and methanolic extracts of volatiles oils of Nigella Sativa seeds were tested against pathogenic bacterias and fungies strains.The volatile oil were found to have significant antifungal and antibacterial activities compare to tetracycline, cefuroxime and ciprofloxacin positive controls.The ether and methanolic esxtracts were compared to each other for antifungal and antibacterial activities and ether extracts showed stonger activity than methanolic one.
Abstract: Novel polystrene-bound Schiff bases and their Pt(IV)
complexes have been prepared from condensation reaction of
polystyrene-A-NH2 with 2-hydroxybenzaldehyde and 5-fluoro-3-
bromo-2-hydroxybenzaldehyde. The structures of Pt(IV) complexes
with polystyrene including Schiff bases have been determined by
elemental analyses, magnetic susceptibility, IR, 1H-NMR, UV-vis,
TG/DTA and AAS. The antibacterial and antifungal activities of the
synthesized compounds have been studied by the well-diffusion
method against some selected microorganisms: (Bacillus cereus spp.,
Listeria monocytogenes 4b, Micrococcus luteus, Staphylococcus
aureus, Staphylococcus epidermis, Brucella abortus, Escherichia
coli, Pseudomonas putida spp., Shigella dysenteria type 10,
Salmonella typhi H).
Abstract: Macrophomina phaseolina is a devastating soil-borne
fungal plant pathogen that causes charcoal rot disease in many
economically important crops worldwide. So far, no registered
fungicide is available against this plant pathogen. This study was
planned to examine the antifungal activity of an allelopathic grass
Cenchrus pennisetiformis (Hochst. & Steud.) Wipff. for the
management of M. phaseolina isolated from cowpea [Vigna
unguiculata (L.) Walp.] plants suffering from charcoal rot disease.
Different parts of the plants viz. inflorescence, shoot and root were
extracted in methanol. Laboratory bioassays were carried out using
different concentrations (0, 0.5, 1.0, …, 3.0 g mL-1) of methanolic
extracts of the test allelopathic grass species to assess the antifungal
activity against the pathogen. In general, extracts of all parts of the
grass exhibited antifungal activity. All the concentrations of
methanolic extracts of shoot and root significantly reduced fungal
biomass by 20–73% and 40–80%, respectively. Methanolic shoot
extract was fractionated using n-hexane, chloroform, ethyl acetate
and n-butanol. Different concentrations of these fractions (3.125,
6.25, …, 200 mg mL-1) were analyzed for their antifungal activity.
All the concentrations of n-hexane fraction significantly reduced
fungal biomass by 15–96% over corresponding control treatments.
Higher concentrations (12.5–200 mg mL-1) of chloroform, ethyl
acetate and n-butanol also reduced the fungal biomass significantly
by 29–100%, 46–100% and 24–100%, respectively.
Abstract: Candida spp. are common and aggressive pathogens. Because of the growing resistance of Candida spp. to current antifungals, novel targets, found in Candida spp. but not in humans or other flora, have to be identified. The alternative oxidase (AOX) is one such possibility. This enzyme is insensitive to cyanide, but is sensitive to compounds such as salicylhydroxamic acid (SHAM), disulfiram and n-alkyl gallates. The growth each of six Candida spp. was inhibited significantly by ~13 mM SHAM or 2 mM cyanide, albeit to differing extents. In C. dubliniensis, C. krusei and C. tropicalis the rate of O2 uptake was inhibited by 18-36% by 25 mM SHAM, but this had little or no effect on C. glabrata, C. guilliermondii or C. parapsilosis. Although SHAM substantially inhibited the growth of Candida spp., it is unlikely that the inhibition of AOX was the cause. Salicylhydroxamic acid is used therapeutically in the treatment of urinary tract infections and urolithiasis, but it also has some potential in the treatment of Candida spp. infection.
Abstract: Among the many promising nanomaterials with antifungal properties, metal nanoparticles (silver nanoparticles) stand out due to their high chemical activity. Therefore, the aim of this study was to evaluate the effect of silver nanoparticles (AgNPs) against Phomopsis sp. AgNPs were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. The synthesized AgNPs have further been characterized by UV/Visible spectroscopy, Biophysical techniques like Dynamic light scattering (DLS) and Scanning Electron Microscopy (SEM). The average diameter of the prepared silver colloidal nanoparticles was about 52 nm. Absolute inhibitions (100%) were observed on treated with a 270 and 540 µg ml-1 concentration of AgNPs. The results from the study of the AgNPs antifungal effect are significant and suggest that the synthesized silver nanoparticles may have an advantage compared with conventional fungicides.
Abstract: We investigate the ZnO role in the inherent protection
of old manuscripts to protect them against environmental damaging
effect of ultraviolet radiation, pollutant gasses, mold and bacteria. In
this study a cellulosic nanocomposite of ZnO were used as protective
coating on the surface of paper fibers. This layered nanocomposite
can act as a consolidate materials too. Furthermore, to determine how
well paper works screen objects from the damaging effects, two
accelerated aging mechanisms due to light and heat are discussed.
Results show good stability of papers with nanocomposite coating.
Also, a good light stability was shown in the colored paper that
treated with this nanocomposite. Furthermore, to demonstrate the
degree of antifungal and antibacterial properties of coated papers,
papers was treated with four common molds and bacteria and the
good preventive effects of coated paper against molds and bacteria
are described.
Abstract: The antimicrobial, antiplasmid and cytotoxic activities of marine algae Halimeda opuntia and Sarconema filiforme were investigated. Antimicrobial bioassay against some human pathogenic bacteria and yeast were conducted using disc diffusion method. Halimeda extract exhibited antibacterial activity against six species of microrganisms, with significant inhibition against Staphylococcus aureus. While Sarconema extract was better potent as antifungal against Candida albicans. Comparative antibacterial studies showed that Halimeda extract showed equivalent or better activity as compared with commercial antibiotic when tested against Staphylococcus aureus. Further tests conducted using dilution method showed both extracts as having bacteriostatic mode of action against the tested microorganisms. Methanol extract of two species showed significant cytotoxicity (LC50
Abstract: White rust, caused by Albugo candida, is the most
destructive foliar diseases of persian cress, Lepidium sativum in Iran.
Application of fungicide is the most common method for the disease
control. However, regarding the problems created by synthetic
pesticides application, environmentally safe methods are needed to
replace chemical pesticides. In this study, the antifungal activity of
plant natural extracts was investigated for their ability to inhibit
zoospore release from sporangia of A. candida. The crude extract of
46 plants was obtained using methanol. The inhibitory effect of the
extracts was examined by mixing the plant extracts with a
zoosporangial suspension of A. candida (1×106 spore/ml) at three
concentrations, 250, 100 and 50 ppm. The experiments were
conducted in a completely randomized design, with three replicates.
The results of the experiment showed that three out of 46 plants
species, including, Rhus coriaria, Anagallis arvensis and Mespilus
germanica were completely inhibit zoospore release from
zoosporangia of Albugo candida at concentration of 50 ppm.
Abstract: This study was conducted to evaluate the antifungal
activities of Cinnamomum zeylanicum and Origanum vulgare L.
essential oil against Aspergillus flavus in culture media and tomato
paste. 200 ppm of cinnamon and 500 ppm of oregano completely
inhibited A. flavus growth in culture media, while in tomato paste 300
ppm of cinnamon and 200 ppm of oregano had the same effect. Test
panel evaluations revealed that samples with 100 and 200 ppm
cinnamon were acceptable. The results may suggest the potential use
of Cinnamomum zeylanicum essential oil as natural preservative in
tomato paste.
Abstract: Candida spp. are common and aggressive pathogens.
Because of the growing resistance of Candida spp. to current
antifungals, novel targets, found in Candida spp. but not in humans
or other flora, have to be identified. The alternative oxidase (AOX)
is one such possibility. This enzyme is insensitive to cyanide, but is
sensitive to compounds such as salicylhydroxamic acid (SHAM),
disulfiram and n-alkyl gallates. The growth Candida albicans was
inhibited by SHAM (Ki = 9-15 mM) and cyanide (Ki = 2-4 mM),
albeit to differing extents. The rate of O2 uptake was inhibited by
less than 10% by 25 mM SHAM and by about 90% by 250 μM
KCN. Although SHAM substantially inhibited the growth of C.
albicans, it is unlikely that the inhibition of AOX was the cause.
Salicylhydroxamic acid is used therapeutically in the treatment of
urinary tract infections and urolithiasis, but it also has some potential
in the treatment of C. albicans infection.
Abstract: Aloe vera has been used worldwide both for
pharmaceutical, food, and cosmetic industries due to the plethora of
biological activities of some of its metabolites. The aim of this study
was to evaluate the antifungal and antioxidant activities of the leaf
extract. The antifungal activity was determined by the agar-well
diffusion method against plant and human fungal pathogens. The
methanol and ethanol portions of the extracts studied were more
bioactive than ethyl acetate portion. It was also observed that the
activity was more pronounced on plant pathogen than human
pathogen except Candida albicans. This is an indication that the
extract has the potential to treat plant fungal infections. The Aloe
extract showed the significant antioxidant activity by the DPPH
radical scavenging method. Therefore, the Aloe extract provided as
natural antioxidant has been used in health foods for medical and
preservative purposes.
Abstract: Lectins have a good scope in current clinical
microbiology research. In the present study evaluated the
antimicrobial activities of a D-galactose binding lectin (PnL) was
purified from the annelid, Perinereis nuntia (polychaeta) by affinity
chromatography. The molecular mass of the lectin was determined to
be 32 kDa as a single polypeptide by SDS-PAGE under both reducing
and non-reducing conditions. The hemagglutinating activity of the
PnL showed against trypsinized and glutaraldehyde-fixed human
erythrocytes was specifically inhibited by D-Gal, GalNAc,
Galβ1-4Glc and Galα1-6Glc. PnL was evaluated for in vitro
antibacterial screening studies against 11 gram-positive and
gram-negative microorganisms. From the screening results, it was
revealed that PnL exhibited significant antibacterial activity against
gram-positive bacteria. Bacillus megaterium showed the highest
growth inhibition by the lectin (250 μg/disc). However, PnL did not
inhibit the growth of gram-negative bacteria such as Vibrio cholerae
and Pseudomonas sp. PnL was also examined for in vitro antifungal
activity against six fungal phytopathogens. PnL (100 μg/mL) inhibited
the mycelial growth of Alternaria alternata (24.4%). These results
indicate that future findings of lectin applications obtained from
annelids may be of importance to life sciences.
Abstract: Bacillus subtilis strain LB5 produced lipopeptide
antibiotic iturin A-2 in liquid medium. Crude extract
from cell-free supernatant of B. subtilis cultivated broth extracted
with n-butanol showed antifungal activity to conidial germination of
Colletotrichum gloeosporioides. The germination of conidia was
completely inhibited by crude extract. The ultrastructure of conidia
after treated with crude extract was found an accumulation of vesiclelike
material between cell wall and plasma membrane while this
accumulation was not observed in untreated and germinated conidia.
Besides, the cell wall was not affected by crude extract.
Abstract: The present study has been taken to explore the
screening of in vitro antimicrobial activities of D-galactose-binding
sponge lectin (HOL-30). HOL-30 was purified from the marine
demosponge Halichondria okadai by affinity chromatography. The
molecular mass of the lectin was determined to be 30 kDa with a
single polypeptide by SDS-PAGE under non-reducing and reducing
conditions. HOL-30 agglutinated trypsinized and glutaraldehydefixed
rabbit and human erythrocytes with preference for type O
erythrocytes. The lectin was subjected to evaluation for inhibition of
microbial growth by the disc diffusion method against eleven human
pathogenic gram-positive and gram-negative bacteria. The lectin
exhibited strong antibacterial activity against gram-positive bacteria,
such as Bacillus megaterium and Bacillus subtilis. However, it did
not affect against gram-negative bacteria such as Salmonella typhi
and Escherichia coli. The largest zone of inhibition was recorded of
Bacillus megaterium (12 in diameter) and Bacillus subtilis (10 mm in
diameter) at a concentration of the lectin (250 μg/disc). On the other
hand, the antifungal activity of the lectin was investigated against six
phytopathogenic fungi based on food poisoning technique. The lectin
has shown maximum inhibition (22.83%) of mycelial growth of
Botrydiplodia theobromae at a concentration of 100 μg/mL media.
These findings indicate that the lectin may be of importance to
clinical microbiology and have therapeutic applications.
Abstract: The effect of antifungal compound from Bacillus
subtilis strain LB5 was tested against conidial germination of
Colletotrichum gloeosporioides and Pestalotiopsis eugeniae, causal
agent of anthracnose and fruit rot of wax apple, respectively.
Observation under scanning electron microscope and light compound
microscope revealed that conidial germination was completely
inhibited when treated with culture broth, culture filtrate, or crude
extract from strain LB5. Identification of purified antifungal
compound produced by strain LB5 in cell-free supernatant by nuclear
magnetic resonance and fast atom bombardment showed that the
active compound was iturin A-2.