This study has been performed to study the inhibitory effects of crude plant extracts of Bay (laurus nobilis) leaves against some bacterial isolates represented by Staphylococcus aureus, Staphylococcus epidermids, Proteus vulgaris, Bacillus subtilis, Escherichia coli, and Pseudomonas aeroginosa in vitro. The results showed that percentages of essential chemical of laurus nobilis leaves which represented by moisture, total oil, total ash, crude protein, crude fibers, carbohydrites and caloric values in dry weight are 5.96, 4.28, 14.2, 8.75, 24.8, 76.99%, and 284.92 kcal/100g respectively, the percentages of some major and minor mineral elements of laurus nobilis leaves powder which represented by Mg, Fe, Cu, Pb, Cd and As, are: 0.211, 0.165, 0.023, 0.011, 0.00, 0.0004 mg/g and 3.140 ppm, respectively, while Co did not appear in the laurus nobilis leaves. The aqueous extract of the plant was acidic its pH 5.79. The results of initial detection (precipitation) showed that ethyl acetate and aqueous extracts of laurus nobilis leaves contain all active compounds represented by tannins, saponins, flavonoides, glycosides, phenols, terpenoids, sterols and cumarin, while alcoholic and hexan extracts contain also the some compounds except saponins, hexane extracts no phenols. Through the study of the effect of laurus nobilis leaves extracts against growth of bacteria in vitro a significant differences at (p<0.05) was observed, It was found that the ethyl acetate and alcoholic extracts more were effective on the bacterial species than the other remaining extracts against the growth of bacteria, inhibitory activity was of all bacterial species at concentration of 3.125mg/ml and it was more effective on Staphyloccocus epidermids for ethyl acetate extract giving inhibitory zone estimated 15.5mm, while alchoholic extract was activity against bacteria E. coli at inhibition zone estimated 15mm, while hexan extracts has been showed inhibition activity of same concentration only on bacteria Staphyloccocus aureus with zone 10.5mm, as for it has been showed inhibitory activity of bacteria Proteus vulgaris at concentration 12.5mg/ml with zone 13mm, as for Staphyloccocus epidermids, Bacillus subtilis, E. coli and Pseudomonas aeroginosa were their inhibition activity at concentration 25mg/ml while Staphyloccocus aureus was highest inhibition at zone 16.5mm and 14mm of same concentration as for the hexan and aqueous extracts respectively, while the inhibition of bacteria Proteus vulgaris was zone 10mm of aqueous extract, inhibitory activity of bacteria Pseudomonas aeroginosa has been showed at concentration 50mg/ml of zone 16mm, as for the bacteria Staphyloccocus epidermids, Bacillus subtilis were the inhibitory zone at 12mm and E. coli at zone 18mm of concentration 100mg/ml. When measuring the minimum inhibitory concentration (MIC) for each bacterial species at a concentrations 6.25- 12.5mg/ml for ethyl acetate and alcoholic extracts have high inhibitory activity compared with the other concentrations, but the hexane and aqueous extracts have affected bacterial species at 12.5- 100 mg/ml, except for Staphyloccocus aureus and Bacillus subtilis, which was not affected by any of the concentrations of extracts.
Corruption (Definition , Characteristics , Reasons , Features , and ways of combating it)
Algae are photosynthetic microorganisms that play important role in aquatic ecosystems as they are the primary producers in aquatic food webs. Several groups of algae are capable of producing toxins that impact aquatic ecosystems, especially managed systems. Cyanobacteria are the most important algae in freshwaters, and many species produce cyanotoxins including hepatotoxins and neurotoxins. The potent cyano-neurotoxins β-N-methylamino-L-alanine (BMAA), 2, 4-diaminobutyric acid dihydrochloride (DABA), and anatoxin-a are especially critical with regards to public and animal health problems.
This research involves studying the mechanical properties and corrosion behavior of “low carbon steel” (0.077wt% C) before and after welding using Arc, MIG and TIG welding. The mechanical properties include testing of microhardness, tensile strength, the results indicate that microhardness of TIG, MIG welding is more than arc welding, while tensile strength in arc welding more than TIG and MIG.
The corrosion behavior of low carbon weldments was performed by potentiostat at scan rate 3mV.sec-1 in 3.5% NaCl to show the polarization resistance and calculate the corrosion rate from data of linear polarization by “Tafel extrapolation method”. The results indicate that the TIG welding increase the corrosion current d
... Show MoreSince the appearance of COVID-19 disease as an epidemic and pandemic disease, many studies are performed to uncover the genetic nature of the newly discovered coronavirus with unique clinical features. The last three human coronavirus outbreaks, SARS-CoV, MERS-CoV and SARS-CoV-2 are caused by Beta-Coronaviruses. Horizontal genetic materials transfer was proven from one coronavirus to the other coronavirus of non-human origin like infectious bronchitis virus (IBV) of avian. Horizontal genetic materials transfer was also from non-corona viruses like astroviruses and equine rhinovirus (ERV-2) or from coronavirus-unrelated viruses, like influenza virus type C. However, SARS-CoV-2 is identical to SARS-CoV and MERS-CoV. Interestingly, Wuhan ci
... Show MoreThe ceramic composite with different proportions of clay and silica was prepared with a grain size of 70 μm and the weight percentage was selected for four groups (clayx silica100-x) were x q15, 25, 30 and 50. In this manuscript, for each pressured sample, a sintering procedure was carried out for 3 hours under static air and at various sintering temperatures (1000, 1100, 1200, 1400)°C. After sintering, the density, porosity, water absorption, compression strength and thermal conductivity were measured. The best results were obtained using a mixture of 15% clay and 85% silica which were sintering at 1400°C for three hours under air.
The study included the investigation of fungi which associated with heavy animal's leather (Cows and Buffalos) and light (Sheep’s and Goats )through different processing stages (raw hides ,dehairing ,pickling,chrome tanned and stainning or finished stages)there were 10 genera and 25 species in addition to sterile fungi associated with animal leathers which included Alternaria ,Aspergillus,Cladosporium,Fusarium, Mucor , Penicillium , Rhizopus , and Trichoderma .Aspergillus and Penicillium have observed in all leather samples and different processing stages, and that the first time isolate two genera Helminthosporium , Stemphylium form leather for staining stage.
The focus of this work is on systematically understanding the effects of packing density of the sand grains on both the internal and bulk mechanical properties for strip footing interacting with granular soil. The studies are based on particle image velocimetry (PIV) method, coupled with a high resolution imaging camera. This provides valuable new insights on the evolution of slip planes at grain-scale under different fractions of the ultimate load. Furthermore, the PIV based results are compared with finite element method simulations in which the experimentally characterised parameters and constitutive behaviour are fed as an input, and a good level of agreements are obtained. The reported results would serve to the practicing engineers, r
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