Authentic representative gum exudate samples from Acacia species namely Acacia senegal var. senegal (ASG), Acacia mellifera (AMF), Acacia seyal var. seyal (ASY), and Acacia tortilis var. raddiana ...(ATR), were physicochemically analyzed. The moisture, ash, nitrogen and protein content, pH, specific optical rotation, and number average molecular weight were found to be ranging from 9.76% to 8.35%, 3.40% to 2.05%, 0.243% to 1.549%, 1.610% to 10.378%, 4.45 to 4.94, −48.25 to +86.75 and 0.24×106 to 2.95×106 respectively. The 13C and 1H NMR spectra of gum samples showed similarity in individual sugar components, but characteristic patterns of each gum, were observed. FTIR spectra of the studied gums show the presence of the same functional groups in the four gums. DSC and TGA thermograms were characteristic for each gum. Evaluation of the functional properties of the four gums indicated that ATR gum bears the best emulsification characteristics in terms of emulsion’s stability and emulsification power.
Bacterial drug resistance poses a global challenge to established antibacterial prevention and treatment schemes. Recent approaches focus on raising algal extracts' efficacy by fusing them to other ...antibacterial agents employing nanotechnology. Here, we successfully biosynthesized AgNPs using Galaxaura rugosa crude methanol extract (AgNP
CR
) and raw powder aqueous (AgNP
AQ
) solution. The resultant AgNPs were characterized using UV-visible spectroscopy, Fourier-transform infrared spectroscopy, dynamic light scattering, and transmission electron microscopy. The AgNPs were spherical and ranged between 60 to 114.4 nm. The presence of the hydroxyl group and alkenes propped AgNPs biosynthesis. We investigated AgNPs antibacterial and antibiofilm activity against eighteen medically important bacteria, including multidrug-resistant bacteria. The sensitive and resistant Acinetobacter baumannii and Staphylococcus aureus were the most affected strains. The biofilm of MDR strains was mostly disturbed, indicating the reduced bacterial fitness in resistant strains. These results may aid antibacterial agents' development by investing in natural resources available abundantly in our environment.
The migration of vinyl chloride monomer (VCM) and plasticizers, especially adipate and phthalate esters, from polyvinyl chloride (PVC) packaging materials into bottled drinking water was ...investigated.
The study has shown that the concentrations of VCM in various brands of bottled-water were below 0.6 ppb, which is far below the 2 ppb maximum contamination limit set by the United States Environmental Protection Agency for VCM in drinking water. Exposure of the bottled-water to sunlight did not result in a measurable increase in the VCM concentration levels. However, several volatile and semi-volatile organic compounds were tentatively identified by GC-MS in the bottled-water after exposure to sunlight.
2,3-Dichloro-l-propanol and dichloroacetic acid were the volatile compounds repeatedly identified, moreover, the presence of benzene was confirmed in some bottled-water samples. Di-n-octyl adipate and bis(2-ethylhexyl) phthalate were the major semi-volatile organic compounds identified. Migration of these compounds were found to depend on storage time, temperature and exposure to sunlight. Di-n-octyl adipate and bis(2-ethylhexyl) phthalate are widely used as plasticezers in PVC packaging materials.
The results of this study suggested that all measures used to store other foodstuffs should be applied to bottled-water to preserve its quality.
An accurate high performance liquid chromatography method for the separation and quantification of a solution mixture of nitrazepam, diazepam and medazepam and medazepam was developed. The modified ...simplex program has been utilized for the optimization of the chemical and chromatographic parameters using the chromatographic response function as the quality criterion and a photodiode array as a detector. The separation was achieved in 2 min using a 20 cm long, 4.6 mm diameter Lichrosorb C18 reverse phase column. A 5
μl solution mixture containing 10 ppm of each drug was injected into a mobile phase containing 89:11 v/v acetonitrile: acetate buffer and a flow rate of 3.44 ml min
−1 was found to be optimal. The method was found to be suitable for the determination of these compounds in proprietary drugs without suffering interferences.
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