The current study aimed to estimate percentage of fatty acids in the husks of local walnut which ... more The current study aimed to estimate percentage of fatty acids in the husks of local walnut which were extracted by maceration with hexane solvent. The results of extract analysis by gas chromatography (GC) showed presence of unsaturated fatty acids with different proportions like stearic acid 0.0184%, linoleic acid 0.0856% and plasmatic acid 0.0347%. The extract showed efficacy against a growth of bacteria with growth inhibition (diameter 15mm) while no effect was seen on the other tested bacterial isolates. The Staphylococcus aureus extract was more effective in spp. than with growth inhibition percentage of 19.11, 26.47 and 47.05 for Penicillium Aspergillus oryzae Aspergillus oryzae
Microbial biofilms are complex communities of bacteria and are common in the human body and in th... more Microbial biofilms are complex communities of bacteria and are common in the human body and in the environment. Many, if not most bacteria which inhabit the oral cavity grow as a biofilm on the non-shedding surfaces of the teeth. Therefore the ability to adhere to the oral surfaces and to grow within a biofilm will give these bacteria a significant advantage in this environment due to the advantages of the biofilm mode of growth, In recent years, dental plaque has been identified as a biofilm, and the structure, microbiology, and pathophysiology of dental biofilms have been described. The nature of the biofilm enhances the component bacteria's resistance (D. Dufour et. al, 2012) to both the host's defense system and antimicrobials. If not removed regularly, the biofilm undergoes maturation, and the resulting pathogenic bacterial complex can lead to dental caries, gingivitis, and periodontitis. In addition, dental biofilm, especially subgingival plaque in patients with periodontitis, has been associated with various systemic diseases (Thomas JG, Nakaishi LA, 2006) and disorders, including cardiovascular disease, diabetes mellitus, respiratory disease, and adverse pregnancy outcomes .
Escherichia coli in fresh minced meat was injured by cooling at 4 ºC. A bacterial population has ... more Escherichia coli in fresh minced meat was injured by cooling at 4 ºC. A bacterial population has three different physiology which are uninjured or normal cells, sublethally injured cells (or injured cells), and lethally injured cells (or dead cells). Cell injury is defined as any damage to the components of cells themselves by any stresses which weaken the ability of cells to survive or multiply. This will increase the sensitivity of cells to any harmful factors. The cells can repair their injury which can be extended 48hour depending on the nature of stress and degree of injury. The purpose of this study was to: supplemented some cultural media and preparation new cultural media to isolated E.coli with compounds that supplemented the bacterial growth such as yeast extract, sodium pyruvate, n-propyl gallate, catalase, and Tween. Various concentrations of the compound were tested minced beef meat with mixed it and compared with traditional media. The rest of the compound had variable effects on the recovery of cold stressed cells but they weren't as efficient as needed. It is, therefore recommended that 0.5% of both catalase and tween 80 be used to supplement tryptic soy agar (TSA) in the repair detection procedure.
The current study was designed to assess the microbial safety status of rice dishes offered for s... more The current study was designed to assess the microbial safety status of rice dishes offered for sale at various local and branded restaurants. Purposely, 30 samples of rice dishes were collected from 16 local and 14 branded restaurants of Baghdad city for two seasons, summer and winter. All the collected samples were subjected to microbiological examination to determine the prevalence and comparative enumeration of: total count, Bacillus cereus, coliform and forming spores in rice. Results pertaining to the enumeration of: total count, Bacillus cereus, coliform and spores forming bacteria exhibited highest count Logarithmic: for summer from collected from: branded restaurants F.S (5.81), and local restaurants coliform (7.82). And winter from collected from: branded restaurants T.C (7.81), and local restaurants coliform (4.44). Highest count observed Bacillus cereus in branded restaurants, and coliform in local restaurants. Further, the results of current study revealed that 42% of rice samples collected from local restaurants and 58% from branded restaurants have unsatisfactory safety status for B. cereus. 38% of rice samples collected from local restaurants and 62% from branded restaurants have unsatisfactory safety status for forming spores. Similarly, for coliform 63 and 42% samples were found unsatisfactory from local and branded restaurants, respectively.
Dextran is an exopolysaccharide (EPS) of bacterial origin that is readily available in the commer... more Dextran is an exopolysaccharide (EPS) of bacterial origin that is readily available in the commercial market. that is used in various industrial applications as an adjuvant, emulsifier, carrier, and stabilizer in the food and biomedical industries. Industrial production of dextran is carried out by fermentation in sucrose-rich media. Studies to optimize dextran production have shown that dextran yield varies depending on specific production conditions. This study aimed to generate dextrans Lactobacillus species were obtained from the vaginal and stool samples of healthy infants. The mucosal technique was employed to determine the biosynthesis of dextran from various isolates of Lactobacillus spp. colony assay and confirmed by isopropanol precipitation. The effects of various parameters such as sucrose concentration, nitrogen concentration, temperature, incubation time, pH, and inoculum size were studied to optimize the maximum dextran yield. In the present study, Weissella cibaria may produce dextran. Optimal conditions for dextran production are a 48-hour incubation at The experimental conditions involved maintaining a temperature of 37°C, with a sugar concentration of 10%, and a yeast extract concentration of 0.5%. The inoculum volume was set at 4%, and the pH level was maintained at 6.5. The experiment was conducted under aerobic conditions. The obtained value for dextran dry weight was 520 mg/100 ml.
The aim study to know the effect of adding kefir on Physical characteristics of bread produced an... more The aim study to know the effect of adding kefir on Physical characteristics of bread produced and on extending the shelf life of the bread. The results showed that the addition of kefir affected the weight of the samples as it reached the control sample 179 gm , and then came samples T3, T4, and T2, reaching (186 , 180, 164) gm respectively. The volume of control bread was higher than those samples with kefir which was 450 ml this agreed with The volume decreased in samples T2, T4 , T3 as they reached (340, 340, 228) ml respectively. The specific weight was recorded in the control treatment the highest percentage, followed by treatment T4, T2, T3, as it reached (2.5 , 2.07 , 1.8 , 1.7) .(ml/gm), respectively. The other parameter of stalling is the volume of precipitate (ppt).No significant different was found for ppt. volume between the control and sample with kefir after 24hrs while samples with kefir had higher ppt.volume after 3 and 5 days comparing with control .as samples with 100% kefir had 26,30ml ppt.volume. Acidity which is parameter of stalling in samples T1, T2, T3, T4 after 24hrs storing it reached (5.1 , 5.3 , 5.4 , 4.5) respectively. while some changes absorved after 3 and 5 days, for sample it reached (5.2 , 5.36 , 5.01 , 4.81) ,(5.1 , 5.36 , 5.01 , 4.8). It was found that the crumb water absorption of water , at room temperature after 24hrs of baking for control and other sample with kefir were not significantly different while there was a significant different between samples with kefir The results showed that all used concentration of kefir contributed in minimize of total number of bacteria of stored bread samples in different periods. The low acidity of kefir as a result of the action of lactic acid bacteria works to reduce bacteria, especially aerobic bacteria. The results of the sensory evaluation of the sample showed that the control treatment obtained the highest evaluation, and it was not a significant difference from treatment T2 and T3 , while treatment T4 received the lowest percentage of sensory evaluation by the evaluators.
Leuconostoc mesetroides, Lactobacillus casei and Lactobacillus rhamnosus GG a lactic acid bacteri... more Leuconostoc mesetroides, Lactobacillus casei and Lactobacillus rhamnosus GG a lactic acid bacteria were evaluated for its ability to remove of cadmium (Cd), lead(Pb) and cobalt(Co) from aqueous solution. The efficiency of whole bacteria was Leuconostoc mesetroides Lactobacillus casei and Lactobacillus rhamnosus GG of Cd metal was 90.848, 83.452, 71.909%, while biofilm was 40.691, 37.131, 37.033%. As for Pb, the highest removal rate for whole bacteria and biofilm for Leuconostoc mesetroides isolation was 91.317% and 72.313% respectively and corresponded to the Co, where the highest removal whole bacteria was by Leuconostoc mesetroides isolation 77.165% As for biofilm it was higher for Lactobacillus casei isolation was 23.359% .Experimental results reveal that all the whole bacterial isolates have potential application for remove of Cd, Pb and Co from the biofilm.
The aim of this investigation, self-healing of cracks in concrete by using named Bacillus Subtili... more The aim of this investigation, self-healing of cracks in concrete by using named Bacillus Subtilis bacteria isolated from agricultural soils and dry soil. Four concrete mixes include, one plain mix without bacteria, other mixes containing a different concentrations of bacteria 10 3 , 10 6 and 10 9 cell/ml respectively were prepared. Hardened properties of concrete water absorption, ultrasonic plus velocity, and compressive strength at 7, 28, 60 and 90 days. Also concrete specimens applied to load 10% of compressive strength at 28 days were studied. The result indicate there is decrease in water absorption of (15-38)%, as well as the decrease in the concrete specimens of loading 10% of compressive strength of (23-41%) relative to control concrete. Increase in compressive resistance of concretes specimens of (6-20)%, (6-17)%, (8-22)% and (7-20)% for ages 7, 28, 60 and 90 days respectively, concrete specimens loaded by 10% of compressive strength, increased by (25-34%) and (34-39%) for 60 and 90 days relative to control concrete. It was observed that the UPV test of concrete specimens was increased. Scanning Electron Micrographic gave an increased in density, deposition of calcite carbonates in the voids and closure of the crack by precipitation of calcium carbonate layers was observed.
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