Formulation of chelating agent with surfactant in cloud point extraction of methylphenol in water.

Cloud point extraction (CPE) is a separation and preconcentration of non-ionic surfactant from one liquid phase to another. In this study, Sylgard 309 and three different types of additives for CPE, namely CPE-Sylgard, CPE-Sylgard-BMIMBr and CPE-Sylgard-GLDA, are investigated to extract methylphenol from water samples. The methylphenols are well separated by reversed-phase high-performance liquid chromatography (HPLC) with isocratic elution of acetonitrile : water; 60 : 40 (v/v) and detection at 260 nm. The optimized parameters for the effect of salt, surfactant, temperature, time of extraction, pH, interference study and the performance of different additives on methylphenol extraction are investigated. CPE-Sylgard-GLDA is chosen because it gives us a high peak and good peak area compared with CPE-Sylgard and CPE-Sylgard-BMIMBr. The recovery extractions of CPE-Sylgard-GLDA are obtained in the range of 80-99% as the percentage of relative standard deviation (RSD) is less than 10. The LOD and LOQ are 0.05 ppm and 0.18 ppm, respectively. The method developed for CPE-Sylgard-GLDA coupled with HPLC is feasible for the determination of methylphenol because it is simple, effective, cheap, and produces a high percentage of recovery.

Screening and identification of quorum sensing degraders from live feed Artemia.

Quorum sensing (QS) is bacterial cell-to-cell communication with small signal molecules such as acyl-homoserine lactones (AHL) that control a number of phenotypes including the regulation of virulence determinants in pathogenic bacteria. Therefore, quorum sensing degrader has been suggested as one of the biocontrol strategies to fight bacterial infections. In the present study, different bacterial QS degrader strains were isolated from Artemia and screened using Chromobacterium violaceum CV026 bioassay. The results showed that six bacterial strains (four Gram-positive and two Gram-negative) isolated from Artemia were able to degrade AHL in two different in vitro assays. All the strains were later identified through 16S rRNA gene sequencing as Rhodococcus opacus, Strepsporangium roseum, Streptomyces alboniger, Enterobacter clocae and Bacillus litoralis. Highest bacterial AHL degrader, Bacillus litoralis BP-ART/6 fully degraded 10 ppm AHL in 9 hrs. The present study showed that bacterial strains isolated from Artemia can act as a QS degrader. ?

Affordable ART for developing countries: a cost benefit comparison of low dose stimulation versus high dose GnRH antagonist protocol.

OBJECTIVE: Low dose stimulation (LS) is emerging as an alternative regime in assisted reproductive technology (ART). This study aimed to compare the cost-effectiveness of LS to the high dose GnRH antagonist (Atg) regime. METHODS: An observational prospective study conducted at an academic infertility unit from January to June 2007. Outcome measures included the numbers of follicles, oocytes and embryos, morphological quality of oocytes and embryos, clinical pregnancy (PR) and complication rate. RESULT: Ninety five first attempt ICSI cycles consisting of 54 LS and 41 Atg were analyzed. Subjects in both groups had comparable sociodemographics and reproductive characteristics. LS generated significantly fewer follicles, total oocytes, mature oocytes (all p < 0.0005) and immature oocytes (p = 0.009) than Atg but the number of excellent quality oocytes was similar. Significantly fewer embryos were available in LS although the proportion of usable embryos was higher, 83.2% vs. 67.0% for Atg. Mean embryos per transfer was 2.0 +/- 1.1 vs. 2.6 +/- 1.0 (p = 0.02) for a clinical PR per transfer of 43.2% vs. 50.0% for LS and Atg respectively. LS regime had a shorter gonadotrophin administration period with resultant COH cost one third of the Atg protocol (both, p < 0.0005). The cost per live birth per started cycle worked out to be USD 13,200 and 24,900 for LS and Atg respectively. Furthermore, LS had fewer incidences of OHSS compared to the Atg regime, 3.7% vs. 12.2%. CONCLUSION: LS cost benefits included lower amounts of gonadotrophin used and fewer injections. It is a viable alternative regime in producing comparable clinical PR at lower cost and less complication in ART.