Organ-specific distribution of chlorophyll-related compounds from dietary spinach in rabbits.

The distribution of chlorophyll-related compounds (CRCs) derived from dietary spinach was investigated in different organs the rabbits. The rabbits in the experimental group consumed 100 g of freeze-dried spinach powder after a 24 h fasting period and sacrificed 2, 4, 8, 12 and 24 h later and in the control group sacrificed after the 24 h fasting period. The main CRCs in the liver were found to be chlorophyll (Chl a) and b, chlorophyllide (Chlide) a and b, pheophytin (Phe) a and b and pheophorbide (Pho) a and b, which reached their peak values at 8 h post-feeding. The gallbladder contained mainly Chlide a and a', Pho a and a', Pho b and b', which peaked their values at 2 h post-feeding. Pho a and b were consistently observed in the blood and peaked at 12 h post-feeding. The earlier appearance of Chlide a', Pho a' and Pho b' in the gallbladder compared to the liver indicated that these CRCs were compartmentalized differently and might undergo the same type of vectorialized transport as characterized for the bile salts. Pho levels peaked later in the blood compared to the liver, suggesting that Pho might be released into the peripheral blood circulation from the liver. In conclusion, Chlide and Pho were the principal Chl metabolites in the rabbits. Our data may expand our understanding of the metabolism and biodistribution of CRCs in the human body. A number of biological functions, including anti-oxidation, anti-tumor and anti-aging have recently been attributed to CRCs, it will be interesting to explore, if the binding of Chlide and Pho to other nutrients or trace metal ions in the body mediate their biological functions.

Development and Validation of RP-HPLC Method for the Determination of Related Compounds in Quetiapine Hemifumarate Raw Material and Tablets.

A simple and sensitive high performance liquid chromatographic method has been developed for the determination of assay quantitative of related compounds and quetiapine hemifumarate in raw material and tablets. Quetiapine hemifumarate is used for the treatment of schizophrenia and there are some generic medicines available in brazilian marketing pharmaceutical, it´s necessary evaluate the quality control of raw material used in the production. Efficient chromatographic separation was carry out on a C18 stationary phase with mobile phase consisting in a mixture of phosphate buffer pH 6.6:Acetonitrile:Methanol (45:40:15), flow rate of 1.0 mL min-1, injection volume of 20 μL, temperature of 25 °C and ultraviolet detection at 220 nm. All of the chromatographic parameters were attended, with resolution greater than 2.9 between quetiapine hemifumarate and impurities. The HPLC method was validated according ICH guidelines, evaluating selectivity, limits of detection and quantification, linearity, accuracy, precision and robustness. The relative retentions times were about 0.58, 0.69 and 0.88 to related compounds, piperazine, lactam and ethanol compound, respectively. Impurities were found < 0.1 % in samples and the assay of quetiapine hemifumarate was > 98.15%. The method can be used for the routine analysis of the impurities in Quetiapine hemihumarate (QH) without any interference.

Effects of carnosine and related compounds on monosaccharide autoxidation and H2O2 formation

The effects of carnosine and related compounds (CRCs) including anserine, homocarnosine, histidine, and beta-alanine on monosaccharide autoxidation and H2O2 formation were investigated. The incubation of CRCs with D-glucose, D-glucosamine, and D, L-glyceraldehyde at 37degreeC increased the absorption maxima at 285 nm, 273 nm, and 290 ~ 330 nm, respectively. D, L-glyceraldehyde was the most reactive sugar with CRCs. The presence of copper strongly stimulated the reaction of carnosine and anserine with D-glucose or D-glucosamine. Carnosine and anserine stimulated H2O2 formation from D-glucose autoxidation in a dose-dependent manner in the presence of 10 muM Cu (II). The presence of human serum albumin (HSA) decreased their effect on H2O2 formation. Carnosine and anserine has a biphasic effect on alpha-ketoaldehyde formation from glucose autoxidation. CRCs inhibited glycation of HSA as determined by hydroxymethyl furfural, lysine residue with free epsilon-amino group, and fructosamine assay. These results suggest that CRCs may be protective against diabetic complications by reacting with sugars and protecting glycation of protein.