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Arthrospira platensis is the widely available source of spirulina that contains distinctive natural pigments, including carotenoids and C-phycocyanin (C-PC). In this study, the major carotenoid and C-PC contents were determined in seven commercially available spirulina powder products and laboratory-prepared A. platensis trichomes (AP-1) by an LC-DAD method and UV-Visible spectrometry, respectively. The correlation of these two pigment content levels with Hunter color coordinates and antioxidant activity was also evaluated. The L* value failed to show a significant correlation with pigment content, but a positive correlation was observed between a* values and the contents of total carotenoid and C-PC. As b* values decreased, the chlorophyll a and C-PC contents increased. AP-1 exhibited the highest content of total carotenoids, chlorophyll a and C-PC, and antioxidant activities among the samples. This observation could be related to degradation of these pigments during the mass production process. The carotenoid profiles suggested that the commercial spirulina powders originated from two different sources, A. platensis and A. maxima. Total carotenoid and C-PC content exhibited positive significant correlations with antioxidant activities measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays. These results provide a strong scientific foundation for the establishment of standards for the commercial distribution of quality spirulina products.

Intravenous lipid emulsions (LEs) are effective in the treatment of toxicity associated with various drugs such as local anesthetics and other lipid soluble agents. The goals of this study were to examine the effect of LE on left ventricular hemodynamic variables and systemic blood pressure in an in vivo rat model, and to determine the associated cellular mechanism with a particular focus on nitric oxide. Two LEs (Intralipid® 20% and Lipofundin® MCT/LCT 20%) or normal saline were administered intravenously in an in vivo rat model following induction of anesthesia by intramuscular injection of tiletamine/zolazepam and xylazine. Left ventricular systolic pressure (LVSP), blood pressure, heart rate, maximum rate of intraventricular pressure increase, and maximum rate of intraventricular pressure decrease were measured before and after intravenous administration of various doses of LEs or normal saline to an in vivo rat with or without pretreatment with the non-specific nitric oxide synthase inhibitor Nω-nitro-L-arginine-methyl ester (L-NAME). Administration of Intralipid® (3 and 10 ml/kg) increased LVSP and decreased heart rate. Pretreatment with L-NAME (10 mg/kg) increased LSVP and decreased heart rate, whereas subsequent treatment with Intralipid® did not significantly alter LVSP. Intralipid® (10 ml/kg) increased mean blood pressure and decreased heart rate. The increase in LVSP induced by Lipofundin® MCT/LCT was greater than that induced by Intralipid®. Intralipid® (1%) did not significantly alter nitric oxide donor sodium nitroprusside-induced relaxation in endothelium-denuded rat aorta. Taken together, systemic blockage of nitric oxide synthase by L-NAME increases LVSP, which is not augmented further by intralipid®.

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We describe three statistical two-sample tests such as the Wilcoxon test, T -test and Kolmogorov±Smirnov test for detecting edges in noisy images. Each of the edge detectors is based on the computation of a test statistic obtained on the modi®ed grey level values by using an edge height parameter which is compared with the threshold given in existing null distribution tables. Some experimental results for these edge detectors with a Sobel operator on sample images both with and without additive noise are given and the performances of these detectors are compared in terms of the quantitative measures.