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Molecular Weight Fraction (molecular + weight_fraction)
Selected AbstractsIn vitro haem solubility of red cell fraction of porcine blood under various treatmentsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2010Tong-Xun Liu Summary An in vitro peptic digestion at gastric pH 2.0 was used to assess the haem solubility of red cell fraction (RCF) of porcine blood derived samples. The in vitro haem solubility of the RCF decreased greatly in the denaturated form of haemoglobin. However, the native haemoglobin was susceptible to be hydrolysed by enzyme mixture of Flavourzyme and Alcalase. The in vitro digestion of the hydrolysates showed that the highest haem solubility was reached at degree of hydrolysis between 8.75% and 12.33%. The in vitro haem solubility was positively correlated with content of the highly soluble peptides with molecular weights ranged from 7.5 kDa to 1 kDa, but negatively with peptides fractions >7.5 kDa and <1 kDa, mostly due to the precipitation of the highly molecular weight fraction (>7.5 kDa) and part of small peptides (<1 kDa) with higher haem/peptide ratio, which was confirmed by gel filtration chromatograms and by the analysis of the precipitate at pH 2.0. [source] Ozonation of complex industrial park wastewater: effects on the change of wastewater characteristicsJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 7 2009Jen-Mao Fanchiang Abstract BACKGROUND: Ozonation of complex industrial park wastewater was carried out in a semi-batch reactor. The variation of wastewater characteristics was evaluated based on the analysis of 5-day biochemical oxygen demand (BOD5) concentration, BOD5/chemical oxygen demand (COD) ratio, COD fractionation, and dissolved organic carbon (DOC) molecular size distribution before and after ozonation. RESULTS: The experimental results indicated that low efficiency of COD removal with increasing tendency of BOD5 concentration generally appeared after ozonation. Also, the BOD5/COD ratio increased from an initial of 0.27 to a maximum of 0.38. The COD fractionation tests revealed that most of the inert soluble COD was transformed to biodegradable soluble COD at 30 min of reaction time. Additionally, the DOC molecular size distribution tests showed that the fraction larger than 500 kDa was significantly decreased and the fraction smaller than 2 kDa was increased when the reaction time was prolonged to 240 min. CONCLUSION: This study verified that partial oxidation of the complex industrial park wastewater by ozonation could enhance wastewater biodegradability. The biodegradability enhancement was primarily because the inert soluble COD fraction was converted to the biodegradable soluble COD and the high molecular weight fraction of DOC was shifted toward the low molecular weight fraction. Copyright © 2009 Society of Chemical Industry [source] Investigation of proteins and peptides from yeastolate and subsequent impurity testing of drug productBIOTECHNOLOGY PROGRESS, Issue 2 2009Lawrence W. Dick Jr. Abstract Hydrolysates play an important role in modern biological production. These mixtures are mostly undefined and contain a mixture of proteins, peptides, and amino acids along with other non,amino acid-based components. Recently, there has been an interest in defining and sequencing proteins and peptides in these hydrolysates to subsequently develop an assay to ensure removal during product purification. This work investigates an ultrafiltrate of yeastolate to determine whether any protein is present. Size exclusion chromatography indicated a possible high molecular weight component (>10 kDa). This suspected high molecular weight fraction was collected and investigated. It was determined that this fraction consists of nucleic acids; and no protein was detected using sensitive modern techniques including HPLC, mass spectrometry, and SDS-PAGE. Next, five unique, yeast-specific peptides were identified, sequenced, and confirmed. Finally, an impurity assay for any residual yeast specific peptides was developed and the analytical metrics were determined including accuracy, precision, linearity, range, and limits of detection and quantitation. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Relationship between antithrombotic activities of fucans and their structureDRUG DEVELOPMENT RESEARCH, Issue 4 2000Catherine Boisson-Vidal Abstract A low molecular weight fucan fraction extracted from the brown seaweed Ascophyllum nodosum was previously shown to exhibit dose-related venous antithrombotic activity with an ED80 of about 20 mg/kg, 2 h after a single subcutaneous injection HCII (Colliec et al. [1991] Thromb Res 64:143,154; Mauray et al. [1995] Thromb Haemast 74:1280,1285). Its activity was comparable to that of a low molecular weight heparin (Dalteparin®). This fucan fraction is one of several, with a range of different structure parameters, prepared by degradation of the whole native fucan. These low molecular weight fractions were compared using a Wessler stasis thrombosis model in rabbits and by determination of their in vitro and ex vivo anticoagulant activities. Intravenous administrations of these fractions reduced thrombosis in a dose-dependent manner. Partial removal of sulfate groups and/or partial degradation lead to a significant decrease in their anticoagulant and antithrombotic activities. The integrity of the regular pattern of sulphation of the fucoidan is necessary for antithrombotic activity. Drug Dev. Res. 51:216,224, 2000. © 2001 Wiley-Liss, Inc. [source] | ||||||||||