Abstract: Soybean Natto powder was added to the burger in order to enhance the oxidative stability as well as decreases the microbial spoilage. The soybean bioactives compound (soybean Natto) as antioxidant and antimicrobial were added at level of 1, 2 and 3%. Chemical analysis and physical properties were affected by soybean Natto addition. All the tested soybean Natto additives showed strong antioxidant properties. The microbiological indicators were significantly (P < 0.05) affected by the addition of the soybean Natto. Decreasing trends of different extent were also observed in samples of the treatments for total viable counts, Coliform, Staphylococcus aureus, yeast and molds. Storage period was significantly (P < 0.05) affected on microbial counts in all samples Staphylococcus aureus were the most sensitive microbe followed by Coliform group of the sample containing soybean Natto. Sensory attributes were also performed, added soybean Natto exhibits beany flavor which was clear about samples of 3% soybean Natto.
Abstract: The present study consisted of an applied test in meat
system to assess the effectiveness of three bio agents bacteriocinproducing
strains: Lm24: Lactobacillus sakei, Lm14and Lm25:
Pediococcus spp. Two tests were carried out: The ex situ test was
intended for three batches added with crude bacteriocin solutions at
12.48 AU/ml for Lm25 and 8.4 AU/ml for Lm14 and Lm24. However, the
in situ one consisted of four batches; three of them inoculated with
one bacteriocinogenic Lm25, Lm14, Lm24, respectively. The fourth one
was used in mixture: Lm14+m24 at approximately of 107 CFU/ml. The
two used tests were done in the presence of the pathogen
St. aureus ATCC 6538, as a test strain at 103 CFU/ml. Another batch
served as a positive or a negative control was used too. The
incubation was performed at 7°C. Total viable counts, staphylococci
and lactic acid bacteria, at the beginning and at selected times with
interval of three days were enumerated. Physico-chemical
determinations (except for in situ test): pH, dry mater, sugars, fat and
total protein, at the beginning and at end of the experiment, were
done, according to the international norms. Our results confirmed the
ex situ effectiveness. Furthermore, the batches affected negatively the
total microbial load over the incubation days, and showed a
significant regression in staphylococcal load at day seven, for Lm14,
Lm24, and Lm25 of 0.73, 2.11, and 2.4 log units. It should be noticed
that, at the last day of culture, staphylococcal load was nil for the
three batches. In the in situ test, the cultures displayed less inhibitory
attitude and recorded a decrease in staphylococcal load, for Lm14,
Lm24, Lm25, Lm14+m24 of 0.73, 0.20, 0.86, 0.032 log units. Therefore,
physicochemical analysis for Lm14, Lm24, Lm25, Lm14+m24 showed an
increase in pH from 5.50 to 5.77, 6.18, 5.96, 7.22, a decrease in dry
mater from 7.30% to 7.05%, 6.87%, 6.32%, 6.00%.This result
reflects the decrease in fat ranging from 1.53% to 1.49%, 1.07%,
0.99%, 0.87%; and total protein from 6.18% to 5.25%, 5.56%,
5.37%, 5.5%. This study suggests that the use of selected strains as
Lm25 could lead to the best results and would help in preserving and
extending the shelf life of lamb meat.
Abstract: In this work we describe the preparation of NanoSilver/methylcellulose hydrogel containing silver nanoparticles (NPs) for topical bactericidal applications. Highly concentrated dispersion of silver NPs as high as of 5g/L of silver with diameter of 10nm was prepared by reduction of AgNO3 via strong reducing agent NaBH4. Silver NPs were stabilized by addition of sodium polyacrylate in order to prevent their aggregation at such high concentration. This way synthesized silver NPs were subsequently incorporated into methylcellulose suspension at elevated temperature resulting in formation of NanoSilver/methylcellulose hydrogel when temperature cooled down to laboratory conditions. In vitro antibacterial activity assay proved high bactericidal and fungicidal efficiency of silver NPs alone in the form of dispersion as well as in the form of hydrogel against broad spectrum of bacteria and yeasts including highly multiresistant strains such as methicillin-resistant Staphylococcus aureus. A very low concentrations of silver as low as 0.84mg/L Ag in as-prepared dispersion gave antibacterial performance. NanoSilver/methylcellulose hydrogel showed antibacterial action at the lowest used silver concentration equal to 25mg/L. Such prepared NanoSilver/methylcellulose hydrogel represent promising topical antimicrobial formulation for treatment of burns and wounds.
Abstract: Mastitis is one of the most economic disease affecting dairy cows worldwide. Its classic diagnosis using bacterial culture and biochemical findings is a difficult and prolonged method. In this research, using of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) permitted identification of different microorganisms with high accuracy and rapidity (only 24 hours for microbial growth and analysis). During the application of MALDI-TOF MS, one hundred twenty strains of Staphylococcus and Streptococcus species isolated from milk of cows affected by clinical and subclinical mastitis were identified, and the results were compared with those obtained by traditional methods as API and VITEK 2 Systems. 37 of totality 39 strains (~95%) of Staphylococcus aureus (S. aureus) were exactly detected by MALDI TOF MS and then confirmed by a nuc-based PCR technique, whereas accurate identification was observed in 100% (50 isolates) of the coagulase negative staphylococci (CNS) and Streptococcus agalactiae (31 isolates). In brief, our results demonstrated that MALDI-TOF MS is a fast and truthful technique which has the capability to replace conventional identification of several bacterial strains usually isolated in clinical laboratories of microbiology.
Abstract: Potential synthesis of a series of 3-amino-4-arylazothiophene derivatives from reaction of 2-cyano-2-phenylthiocarbamoyl acetamide and the appropriate α-halogenated reagents, followed by coupling with different aryl diazonium salts (Japp-Klingemann reaction), and another series of 5-arylazo-thiazol-2-ylcarbamoyl-thiophene derivatives from base-catalyzed intramolecular condensation of 5-arylazo-2-(N-chloroacetyl)amino-thiazole with selected b-keto compounds (Thorpe-Ziegler reaction) was performed. The biological activity of the two series was studied in vitro. Their versatility for pharmaceutical purposes was reported, where they displayed remarkable activities against selected pathogenic microorganisms; Bacillus subtilis, Staphylococcus aureus (Gram positive bacteria), Escherichia coli, Pseudomonas aeruginosa (Gram negative bacteria), and Aspergillus flavus, Candida albicans (fungi) with various degrees related to their chemical structures.
Abstract: The aim of the present work was to test in vitro inhibition of food pathogens and spoilage bacteria by crude bacteriocins from autochthonous lactic acid bacteria. Thirty autochthonous lactic acid bacteria isolated previously, belonging to the genera: Lactobacillus, Carnobacterium, Lactococcus, Vagococcus, Streptococcus, and Pediococcus, have been screened by an agar spot test and a well diffusion assay against Gram-positive and Gram-negative harmful bacteria: Bacillus cereus, Bacillus subtilis ATCC 6633, Escherichia coli ATCC 8739, Salmonella typhimurium ATCC 14028, Staphylococcus aureus ATCC 6538, and Pseudomonas aeruginosa under conditions means to reduce lactic acid and hydrogen peroxide effect to select bacteria with high bacteriocinogenic potential. Furthermore, crude bacteriocins semiquantification and heat sensitivity to different temperatures (80, 95, 110°C, and 121°C) were performed. Another exploratory test concerning the response of St. aureus ATCC 6538 to the presence of crude bacteriocins was realized. It has been observed by the agar spot test that fifteen candidates were active toward Gram-positive targets strains. The secondary screening demonstrated an antagonistic activity oriented only against St. aureus ATCC 6538, leading to the selection of five isolates: Lm14, Lm21, Lm23, Lm24, and Lm25 with a larger inhibition zone compared to the others. The ANOVA statistical analysis reveals a small variation of repeatability: Lm21: 0.56%, Lm23: 0%, Lm25: 1.67%, Lm14: 1.88%, Lm24: 2.14%. Conversely, slight variation was reported in terms of inhibition diameters: 9.58± 0.40, 9.83± 0.46 and 10.16± 0.24 8.5 ± 0.40 10 mm for, Lm21, Lm23, Lm25, Lm14and Lm24, indicating that the observed potential showed a heterogeneous distribution (BMS = 0.383, WMS = 0.117). The repeatability coefficient calculated displayed 7.35%. As for the bacteriocins semiquantification, the five samples exhibited production amounts about 4.16 for Lm21, Lm23, Lm25 and 2.08 AU/ml for Lm14, Lm24. Concerning the sensitivity the crude bacteriocins were fully insensitive to heat inactivation, until 121°C, they preserved the same inhibition diameter. As to, kinetic of growth , the µmax showed reductions in pathogens load for Lm21, Lm23, Lm25, Lm14, Lm24 of about 42.92%, 84.12%, 88.55%, 54.95%, 29.97% in the second trails. Inversely, this pathogen growth after five hours displayed differences of 79.45%, 12.64%, 11.82%, 87.88%, 85.66% in the second trails, compared to the control. This study showed potential inhibition to the growth of this food pathogen, suggesting the possibility to improve the hygienic food quality.
Abstract: Antimicrobial activities of aminoreductone (AR), a product formed in the initial stage of Maillard reaction, were screened against pathogenic bacteria. A significant growth inhibition of AR against all 7 isolates (Staphylococcus aureus ATCC® 25923™, Salmonella typhimurium ATCC® 14028™, Bacillus cereus ATCC® 13061™, Bacillus subtilis ATCC® 11774™, Escherichia coli ATCC® 25922™, Enterococcus faecalis ATCC® 29212™, Listeria innocua ATCC® 33090™) were observed by the standard disc diffusion methods. The inhibition zone for each isolate by AR (2.5 mg) ranged from 15±0mm to 28.3±0.4mm in diameter. The minimum inhibitory concentration (MIC) of AR ranging from 20mM to 26mM was proven in the 7 isolates tested. AR also showed the similar effect of growth inhibition in comparison with antibiotics frequently used for the treatment of infections bacteria, such as amikacin, ciprofloxacin, meropennem and levofloxacin. The results indicated that foods containing AR are valuable sources of bioactive compounds towards pathogenic bacteria.
Abstract: Chitosan is a derivative of chitin, a compound usually
isolated from the shells of some crustaceans such as crab, lobster and
shrimp. It has biocompatible, biodegradable, and antimicrobial
properties. To use these properties of chitosan in biomedical fields,
chitosan films (1%, 2%, 3% and 4%) were prepared by using l%
lactic acid as solvent. The effects of chitosan films on tensile
strength, elongation at break, degree of swelling, thickness,
morphology, allergic and irritation reactions and antibacterial
property were evaluated. Staphylococcus aureus and Escherichia coli
were used as tested microorganisms. In vivo wound healing activities
of chitosan films were investigated using mice model. As results,
Chitosan films have similar appearance and good swelling properties
and 4% chitosan film showed the better swelling activity and the
greatest elongation ratio than the other chitosan films. They also
showed their good activity of wound healing in mice model.
Moreover, the results showed that the films did not produce any
unwilling symptoms (allergy or irritation). In conclusion, it is evident
that the chitosan film has the potentiality to use as wound healing
biofilms in the biomedical fields.
Abstract: In this study the extracts of the Iraqi herb Tribulus
terrestris (Al-Hassage or Al-Kutub) was done by using of polar and
non polar solvents, then the biological activity of these extractants
was studied in three fields, First, the antibacterial activity (in vitro)
on gram positive bacteria (Staphylococcus aureus), and gram
negative bacteria (E. coli, Proteus vulgaris, Pseudomonas
aerugiuosa, and Klebsiella), all extracts showed considerable activity
against all bacteria. Second, the effect of extracts on free serum
testosterone level in male mice (in vivo), the alcoholic, and
acetonitrilic extracts showed significant (P < 0.05) increase in free
serum testosterone level, and we found that the extracts contained
compounds with less genotoxic effects in mice germ cells. 3rd, was to
study the effect of methanolic extract of T. terrestris in diabetes
management.
Abstract: Silver-exchanged zeolites and clays are used in
polymer composites to confer broad-spectrum antimicrobial
properties on a range of functional materials. Tobermorite is a layer
lattice mineral whose potential as a carrier for Ag+ ions in
antibacterial composites has not yet been investigated. Accordingly,
in this study, synthetic tobermorite was ion-exchanged with 10 wt%
silver ions and the resulting material was incorporated into a
composite film with chitosan. Chitosan is a biocompatible,
biodegradable derivative of chitin, a polysaccharide obtained from
the shells of crustaceans. The solvent-cast Ag+-exchanged
tobermorite-chitosan films were found to exhibit antimicrobial action
against Staphylococcus aureus, Escherichia coli and Pseudomonas
aeruginosa.
Abstract: This study was carried out to reveal the bacterial composition of aerosol in the studied abattoirs. Bacteria isolated were characterized according to microbiological standards. Factors such as temperature and distance were considered as variable in this study. The isolation was carried out at different temperatures such as 27oC, 31oC and 29oC and at various distances of 100meters and 200meters away from the slaughter sites. Result obtained showed that strains of Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Lactobacillus alimentarius and Micrococcus sp. were identified. The total viable counts showed that more microorganisms were present in the morning while the least viable count of 388cfu was recorded in the evening period of this study. This study also showed that more microbial loads were recorded the further the distance is to the slaughter site. Conclusively, the array of bacteria isolated suggests that abattoir sites may be a potential source of pathogenic organisms to commuters if located within residential environment.
Abstract: In this research, the main aim is to investigate the
antimicrobial effectiveness of ammonyx solutions finishing on
Sweatshirt Sport with immersion method. 60 Male healthy subjects
(football player) participated in this study. They were dressed in a
Sweatshirt for 14 days and some microbes found on them were
investigated. The antimicrobial effect of different ammonyx
solutions(1/100, 1/500, 1/1000, 1/2000 v/v solutions of Ammonyx)
on the identified microbes was studied by the zone inhabitation
method in vitro. In the next step the Sweatshirt Sports were treated
with the same different solutions of ammonyx and the antimicrobial
effectiveness was assessed by colony count method in different times
and the results were compared whit untreated ones. Some mechanical
properties of treated cotton/polyester yarn that used in Sweatshirt
Sport were measured after 30 days and were compared with
untreated one. Finally after finishing, scanning electron microscopy
(SEM) was used to compare the surfaces of the finished and
unfinished specimens. The results showed the presence of five
pathogenic microbes on Sweatshirt Sports such as Escherichia coli,
Staphylococcus aureus, Aspergillus, Mucor and Candida. The
inhalation time for treated on Sweatshirt Sports improved. The
amount of colony growth on treated clothes reduced considerably
and moreover the mechanical tests results showed no significant
deterioration effect of studies properties in comparison to the
untreated yarn. The visual examination of the SEM indicated that the
antimicrobial treatments were applied usefully to fabrics.
Abstract: Alcohol and water extracts of Cymbopogon citratus
was investigated for anti-bacterial properties and phytochemical
constituents. The extract was screened against four gram-negative
bacteria Escherichia coli, Klebsiella pneumoniae, Pseudomonas
aeruginosa, Proteus vulgaris) and two grampositive bacteria Bacillus
subtilis and Staphylococcus aureus at four different concentrations
(1:1, 1:5, 1:10 and 1:20) using disc diffusion method. The antibacterial
examination was by disc diffusion techniques, while the
photochemical constituents were investigated using standard
chemical methods. Results showed that the extracts inhibited the
growth of standard and local strains of the organisms used. The
treatments were significantly different (P = 0.05). The minimum
inhibitory concentration of the extracts against the tested
microorganisms ranged between 150mg/ml and 50mg/ml. The
alcohol extracts were found to be generally more effective than the
water extract. The photochemical analysis revealed the presence of
alkaloids and phenol but absence of cardiac and cyanogenic
glycosides. The presence of alkaloid and phenols were inferred as
being responsible for the anti-bacterial properties of the extracts.
Abstract: Staphylococcus aureus, one of the microflora in a
human external auditory canal (EAC) is frequently exposed to highfrequency
electromagnetic field (HF-EMF) generated by mobile
phones. It is normally non-pathogenic but in certain circumstances, it
can cause infections. This study investigates the changes in the
physiology of S. aureus when exposed to HF-EMF of a mobile
phone. Exponentially grown S. aureus were exposed to two
conditions of EMF irradiation (standby-mode and on-call mode) at
four durations; 15, 30, 45 and 60 min. Changes in the viability and
biofilm production of the S. aureus were compared between the two
conditions of exposure. EMF from the standby-mode has enhanced
the growth of S. aureus but during on-call, the growth was
suppressed. No significant difference in the amount of biofilm
produced in both modes of exposure was observed. Thus, HF-EMF
of mobile phone affects the viability of S. aureus but not its ability to
produce biofilm.
Abstract: Sediment and mangrove root samples from Iko River
Estuary, Nigeria were analyzed for microbial and polycyclic
aromatic hydrocarbon (PAH) content. The total heterotrophic
bacterial (THB) count ranged from 1.1x107 to 5.1 x107 cfu/g, total
fungal (TF) count ranged from 1.0x106 to 2.7x106 cfu/g, total
coliform (TC) count ranged from 2.0x104 to 8.0x104cfu/g while
hydrocarbon utilizing bacterial (HUB) count ranged from 1.0x 105 to
5.0 x 105cfu/g. There was a range of positive correlation (r = 0.72 to
0.93) between THB count and total HUB count, respectively. The
organisms were Staphylococcus aureus, Bacillus cereus,
Flavobacterium breve, Pseudomonas aeruginosa, Erwinia
amylovora, Escherichia coli, Enterobacter sp, Desulfovibrio sp,
Acinetobacter iwoffii, Chromobacterium violaceum, Micrococcus
sedentarius, Corynebacterium sp, and Pseudomonas putrefaciens.
The PAH were Naphthalene, 2-Methylnaphthalene, Acenapthylene,
Acenaphthene, Fluorene, Phenanthene, Anthracene, Fluoranthene,
Pyrene, Benzo(a)anthracene, Chrysene, Benzo(b)fluoranthene,
Benzo(k)fluoranthene, Benzo(a)pyrene, Dibenzo(a,h)anthracene,
Benzo(g,h,l)perylene ,Indeno(1,2,3-d)pyrene with individual PAH
concentrations that ranged from 0.20mg/kg to 1.02mg/kg, 0.20mg/kg
to 1.07mg/kg and 0.2mg/kg to 4.43mg/kg in the benthic sediment,
epipellic sediment and mangrove roots, respectively. Total PAH
ranged from 6.30 to 9.93mg/kg, 6.30 to 9.13mg/kg and 9.66 to
16.68mg/kg in the benthic sediment, epipellic sediment and
mangrove roots, respectively. The high concentrations in the
mangrove roots are indicative of bioaccumulation of the pollutant in
the plant tissue. The microorganisms are of ecological significance
and the detectable quantities of polycyclic aromatic hydrocarbon
could be partitioned and accumulated in tissues of infaunal and
epifaunal organisms in the study area.
Abstract: Dried soy protein hydrolysate powder was added to
the burger in order to enhance the oxidative stability as well as
decreases the microbial spoilage. The soybean bioactive compounds
(soy protein hydrolysate) as antioxidant and antimicrobial were added
at level of 1, 2 and 3 %.Chemical analysis and physical properties
were affected by protein hydrolysate addition. The TBA values were
significantly affected (P < 0.05) by the storage period and the level of
soy protein hydrolysate. All the tested soybean protein hydrolysate
additives showed strong antioxidant properties. Samples of soybean
protein hydrolysate showed the lowest (P < 0.05) TBA values at each
time of storage.
The counts of all determined microbiological indicators were
significantly (P < 0.05) affected by the addition of the soybean
protein hydrolysate. Decreasing trends of different extent were also
observed in samples of the treatments for total viable counts,
Coliform, Staphylococcus aureus, yeast and molds. Storage period
was being significantly (P < 0.05) affected on microbial counts in all
samples Staphylococcus aureus were the most sensitive microbe
followed by Coliform group of the sample containing protein
hydrolysate, while molds and yeast count showed a decreasing trend
but not significant (P < 0.05) until the end of the storage period
compared with control sample. Sensory attributes were also
performed, added protein hydrolysate exhibits beany flavor which
was clear about samples of 3% protein hydrolysate.
Abstract: The aim of this study was to assess the effect of LAB
isolated from Iranian native olives on the opportunistic skin
pathogens, Pseudomonas aeruginosa and Staphylococcus aureus.
Lactic Acid Bacteria were isolated from the brine of each sample in
the prior of time. The samples were spread on MRS agar for isolation
of lactobacillus and for lactococcus. 28 strains of labs were isolated.
The labs were centrifuged, the supernatant was strewed and pellet
was used to inoculation in wells or at blank disks. 20μl of each pellet
was inoculated to blank disks and 40μl of each pellet was inoculated
to each well. The result of disk and well diffusion agar against these
pathogens were confirmed each other. The size of inhibition zone
was different according to the type of bacteria, the method and the
concentrations of labs.
Abstract: Plants are rich sources of bioactive compounds. In this study the photochemical screening of hexane, ethanolic and aqueous extracts of roots and latex of jojoba (Simmondsia chinensis) plant revealed the presence of saponins, tannins, alkaloids, steroids and glycosides. Ethanolic extract was found to be richer in these metabolites than hexane, aqueous extracts and latex. The extracts and latex displayed effective antimicrobial activity against Salmonella typhimurium, Bacillus cereus, Clostridium perfringens, Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus flavus. The increase in volume of the extracts and latex caused more activity, as shown by zones of inhibition. Candida albicans growth was inhibited only by hexane extract. Jojoba latex was not effective against Candida albicans at 0.1 and 0.5 ml extracts concentration but showed 5mm zone of inhibition at (1.0 ml). Lower volume (0.1ml) of latex encouraged Aspergillus flavus growth, while at (1.00 ml) reduced its mycelial growth. Thus, jojoba root extracts and latex can be of potential natural antimicrobial agents.
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: Silver nanoparticles were prepared by chemical reduction method. Silver nitrate was taken as the metal precursor and hydrazine hydrate as a reducing agent. The formation of the silver nanoparticles was monitored using UV-Vis absorption spectroscopy. The UV-Vis spectroscopy revealed the formation of silver nanopart├¡cles by exhibing the typical surface plasmon absorption maxima at 418-420 nm from the UV–Vis spectrum. Comparison of theoretical (Mie light scattering theory) and experimental results showed that diameter of silver nanoparticles in colloidal solution is about 60 nm. We have used energy-dispersive spectroscopy (EDX), X-ray diffraction (XRD), transmission electron microscopy (TEM) and, UV–Vis spectroscopy to characterize the nanoparticles obtained. The energy-dispersive spectroscopy (EDX) of the nanoparticles dispersion confirmed the presence of elemental silver signal no peaks of other impurity were detected. The average size and morphology of silver nanoparticles were determined by transmission electron microscopy (TEM). TEM photographs indicate that the nanopowders consist of well dispersed agglomerates of grains with a narrow size distribution (40 and 60 nm), whereas the radius of the individual particles are between 10 and 20 nm. The synthesized nanoparticles have been structurally characterized by X-ray diffraction and transmission high-energy electron diffraction (HEED). The peaks in the XRD pattern are in good agreement with the standard values of the face-centered-cubic form of metallic silver (ICCD-JCPDS card no. 4-0787) and no peaks of other impurity crystalline phases were detected. Additionally, the antibacterial activity of the nanopart├¡culas dispersion was measured by Kirby-Bauer method. The nanoparticles of silver showed high antimicrobial and bactericidal activity against gram positive bacteria such as Escherichia Coli, Pseudimonas aureginosa and staphylococcus aureus which is a highly methicillin resistant strain.