This study was designed to evaluate the antimicrobial effect of Cymbopogon citratus and Mentha spicata essential oils, separately and mixed, against the microorganisms in yogurt, as well as study the possibility of these essential oils (EO) as natural preservatives and flavors additives/enhancers in yogurt product. Yogurt samples were treated with lemongrass and spearmint EOin different concentrations (250, 500, 1000 ppm: 6250µg/50 ml yogurt, 12500 µg/50 ml yogurt and 25000 µg/50 ml yogurt respectively). The control and treated samples were preserved both at room (25°C) and refrigerator (5°C) temperatures. In control, the contamination was observed through 2 weeks at 25°C and for about one month at 5°C. The samples treated with lemongrass and spearmint EOs (500pmm), the contamination showed up late, after 45 and 30 days at 25°C respectively. While at 5°C, the contamination appeared after 90 and 60 days respectively. The effect of lemongrass and spearmint EO, separately or mixed (synergistic effect), on the growth of fungi that was isolated from spoiled samples, was studied in different concentrations (125, 250, 500 ppm). Microbilogical examination was done in the control and treated yogurt samples. There was a significant difference (P≤ 0.05) between microbial spoilage (coliform, yeast and fungi) count during different periods of incubation which decreased in the samples treated with essential oils as compared with the control. The results of the percentage of growth inhibition revealed that lemongrass EO, around 80-100%, is the best in inhibiting the molds and yeasts causing yogurt damage as compared to the use of spearmint EO which was 27-60%, and the synergistic effect of about 35-39%. The results of the toxicity assay of the maximum effect of EO in vivo proved their validity for consumption when added both as preservative and flavor. The concentrations used for the dosage ranged from 250 ppm to 5000 ppm.
The title compound was synthesized by 2:1 condensation between adamantan-1-ylamine and benzene-1,4- dicarbaldehyde in n-BuOH and produced a good yield 87% of new bis Schiff base. The compound skeleton was affirmed by FTIR, 1H NMR, LC-MS, and X-ray powder diffraction. The structure was solved by a parallel tempering process and refined by using Rietveld refinement. Two adamantan-1-ylimino groups are connected in the anti-positions to the planar central 1,4-dimethylbenzene group. All rings of the adamantyl group possess normal chair conformation.
This study depicts the removal of Manganese ions (Mn2+) from simulated wastewater by combined electrocoagulation/ electroflotation technologies. The effects of initial Mn concentration, current density (C.D.), electrolysis time, and different mesh numbers of stainless steel screen electrodes were investigated in a batch cell by adopting Taguchi experimental design to explore the optimum conditions for maximum removal efficiency of Mn. The results of multiple regression and signal to noise ratio (S/N) showed that the optimum conditions were Mn initial concentration of 100 ppm, C.D. of 4 mA/cm2, time of 120 min, and mesh no. of 30 (wire/inch). Also, the relative significance of each factor was attained by the analysis of variance (ANO
... Show MoreNowadays, most of the on-chip plasmonic single-photon sources emit an unpolarized stream of single photons that demand a subsequent polarizer stage in a practical quantum cryptography system. In this paper, we numerically demonstrated the coupling of the light emitted from a quantum emitter (QE) at 700 nm wavelength to the propagation mode supported by an on-chip hybrid plasmonic waveguide (HPW) polarization rotator. Our results proved that the light emitted is linearly polarized at 0º, 45º/−45º, and 90º with propagation lengths of 5 μm, 3.3 μm, and 3.9 μm, respectively. Moreover, high power-conversion efficiency was obtained from an applied transverse magnetic (TM) mode (0º-polarization) to a transverse electric (TE) (90º-polari
... Show MoreThe present study aimed to use the magnetic field and nanotechnology in the field of water purification, which slots offering high efficiency to the possibility of removing biological contaminants such as viruses and bacteria rather than the use of chemical and physical transactions such as chlorine and bromine, and ultraviolet light and boiling and sedimentation and distillation, ozone and others that have a direct negative impact on human safety and the environment. Where they were investigating the presence in water samples under study Coli phages using Single agar layer method and then treated samples positive for phages to three types of magnetic field fixed as follows (North Pole - South Pole - Bipolar) and compare the re
... Show MoreA new, simple, sensitive and fast developed method was used for the determination of methyldopa in pure and pharmaceutical formulations by using continuous flow injection analysis. This method is based on formation a burgundy color complex between methyldopa andammonium ceric (IV) nitrate in aqueous medium using long distance chasing photometer NAG-ADF-300-2. The linear range for calibration graph was 0.05-8.3 mmol/L for cell A and 0.1-8.5 mmol/L for cell B, and LOD 952.8000 ng /200 µL for cell A and 3.3348 µg /200 µL for cell B respectively with correlation coefficient (r) 0.9994 for cell A and 0.9991 for cell B, RSD % was lower than 1 % for n=8. The results were compared with classical method UV-Spectrophotometric at λ max=280 n
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