(C) 2011 American Institute of Physics. [doi:10.1063/1.3536788]“
“The phytochemical constituents and antimicrobial properties of the aqueous extract of Cassia arereh stem-bark were evaluated. The extract was subjected to qualitative chemical screening of active chemical constituents and disc diffusion method was performed to determine the antimicrobial Pfizer Licensed Compound Library price properties. The results revealed the presence of tannins, phlobatannins, carbohydrate, saponin, flvonoids, terpenes and steroids while anthraquinones, alkaloids and cardiac glycosides were not detected. The extracts (100, 200, 400 and 800 mg/ml) inhibited the growth of Staphylococcus aureus, Bacillus subtilis, Salmonella typhi, Pseudomonas

aerogenosa and Enterobacter species. However, Escherichia coli, Klebsiella pneumoniae, Corynebacterium pyogenes and Candida albicans were resistant. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were 50 mg/ml for S. aureus and B. subtilis, and 100 mg/ml for P. aeurogenosa. It was concluded that the aqueous extract of C. arereh stem-bark contained active principles having antibacterial properties and thus support the folkloric use of the plant.”
“A poly(acrylamide) (PAM) aqueous dispersion with high solid was successfully synthesized

through two-phase polymerization of acrylamide (AM) in aqueous poly(ethylene glycol) (PEG) solution. To prepare stable PAM aqueous dispersion, PF-04929113 nmr the effects of initiator, monomer and PEG concentration on the AR-13324 order stability of the aqueous two-phase polymerization system were investigated in detail. Dynamic light scattering (DLS) was applied to study the evolution of the size and size distribution of the aqueous PAM droplet in the initial stage of polymerization. A droplet aggregation period was found in the initial stage, in which the PAM coagulum is easy to be generated below the conversion of about 5% due to high

polymerization rate. By analyzing the effects of PEG on the stability of this polymerization system, it was found that PEG plays both precipitant and stabilizer role. When PEG concentration ranges from 12 to 24%, increasing its use would pro-mote the droplet stabilization; however, when PEG concentration exceeds 28%, increasing its use may accelerate the droplet formation which does not further favor the droplet stabilization. Furthermore, the viscosity evolution during the polymerization under various reaction conditions was determined by rotational viscometer on line. When monomer concentration exceeded 8%, increasing the initiator or monomer concentration would result in that the polymer produced in the continuous phase could not be separated in time due to the high viscosity. All these results demonstrated that the slower the polymerization rate is, the more stable PAM aqueous dispersion will be. (C) 2011 Wiley Periodicals, Inc.