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Biotechnological Products (biotechnological + products)
Selected AbstractsColloid deposition experiments as a diagnostic tool for biomass attachment onto bioproduct adsorbent surfacesJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 2 2008Canan Tari Abstract BACKGROUND: Detrimental processing conditions can be expected in any downstream operation where direct contacting between a crude feedstock and a reactive solid phase is supposed to occur. In this paper we have investigated the factors influencing intact yeast cells deposition onto anion and cation exchangers currently utilized for expanded-bed adsorption of biotechnological products. The aim of this study was twofold: (a) to confirm previous findings relating biomass deposition with surface energetics according to the extended Derjaguin, Landau, Verwey and Overbeek theory (XDLVO) theory; and (b) to provide a simple experimental tool to evaluate biomass deposition onto process surfaces. RESULTS:Biomass deposition experiments were performed on an automated workstation utilizing a packed-bed format. Two commercial ion exchangers intended for the direct capture of bioproducts in the presence of suspended biological particles were employed. Intact yeast cells in the late exponential phase of growth were selected as model bio-colloids. Cell deposition was systematically evaluated as a function of fluid-phase conductivity and quantitatively expressed as a biomass deposition parameter (,). CONCLUSION: , ,0.15 was established as a criterion to reflect negligible biomass adhesion to the process support(s). Biomass deposition experiments further confirmed predictions made on the basis of free interfacial energy calculations as per the extended DLVO approach. Copyright © 2008 Society of Chemical Industry [source] Proactive consumer consultation: the effect of information provision on response to transgenic animalsJOURNAL OF PUBLIC AFFAIRS, Issue 3-4 2005David Castle A national study is reported which proactively engaged 1365 Canadian consumers and solicited their opinions concerning new transgenic salmon and pork products which have not yet entered the marketplace. Respondents were methodically requested to provide initial free-association responses, and then scaled responses to product concepts about which progressively more information was revealed. This combined qualitative and quantitative method was pursued in order to determine initial knowledge levels and subsequent responses with a minimal amount of cueing via question probes. The results indicate that disclosure concerning benefits and risks of these new technologies did not harm judgements about them or estimates of purchase intent. A significant determinant of opinions was the gender of the respondent. Females were more negatively predisposed overall to the concepts and more sensitive to specific information regarding product benefits and risks. The research offers a methodological template for public consultation and communication pre-testing for new biotechnological products. Implications for regulatory policy and information dissemination for new food biotechnology products are discussed. Copyright © 2005 John Wiley & Sons, Ltd. [source] Affinity-enhanced protein partitioning in decyl ,- D -glucopyranoside two-phase aqueous micellar systemsBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2005Henry Lam Abstract Liquid,liquid extraction in two-phase aqueous complex-fluid systems has been proposed as a scalable, versatile, and cost-effective purification method for the downstream processing of biotechnological products. In the case of two-phase aqueous micellar systems, careful choices of the phase-forming surfactants or surfactant mixtures allow these systems to separate biomolecules based on size, hydrophobicity, charge, or specific affinity. In this article, we investigate the affinity-enhanced partitioning of a model affinity-tagged protein,green fluorescent protein fused to a family 9 carbohydrate-binding module (CBM9-GFP),in a two-phase aqueous micellar system generated from the nonionic surfactant n -decyl ,- D -glucopyranoside (C10G1), which acts simultaneously as the phase-former and the affinity ligand. In this simple system, CBM9-GFP was extracted preferentially into the micelle-rich phase, despite the opposing tendency of the steric, excluded-volume interactions operating between the protein and the micelles. We obtained more than a sixfold increase (from 0.47 to 3.1) in the protein partition coefficient (Kp), as compared to a control case where the affinity interactions were "turned off" by the addition of a competitive inhibitor (glucose). It was demonstrated conclusively that the observed increase in Kp can be attributed to the specific affinity between the CBM9 domain and the affinity surfactant C10G1, suggesting that the method can be generally applied to any CBM9-tagged protein. To rationalize the observed phenomenon of affinity-enhanced partitioning in two-phase aqueous micellar systems, we formulated a theoretical framework to model the protein partition coefficient. The modeling approach accounts for both the excluded-volume interactions and the affinity interactions between the protein and the surfactants, and considers the contributions from the monomeric and the micellar surfactants separately. The model was shown to be consistent with the experimental data, as well as with our current understanding of the CBM9 domain. © 2005 Wiley Periodicals, Inc. [source] Optimal Synthesis of Protein Purification ProcessesBIOTECHNOLOGY PROGRESS, Issue 4 2001Elsa Vásquez-Alvarez There has been an increasing interest in the development of systematic methods for the synthesis of purification steps for biotechnological products, which are often the most difficult and costly stages in a biochemical process. Chromatographic processes are extensively used in the purification of multicomponent biotechnological systems. One of the main challenges in the synthesis of purification processes is the appropriate selection and sequencing of chromatographic steps that are capable of producing the desired product at an acceptable cost and quality. This paper describes mathematical models and solution strategies based on mixed integer linear programming (MILP) for the synthesis of multistep purification processes. First, an optimization model is proposed that uses physicochemical data on a protein mixture, which contains the desired product, to select a sequence of operations with the minimum number of steps from a set of candidate chromatographic techniques that must achieve a specified purity level. Since several sequences that have the minimum number of steps may satisfy the purity level, it is possible to obtain the one that maximizes final purity. Then, a second model that may use the total number of steps obtained in the first model generates a solution with the maximum purity of the product. Whenever the sequence does not affect the final purity or more generally does not impact the objective function, alternative models that are of smaller size are developed for the optimal selection of steps. The models are tested in several examples, containing up to 13 contaminants and a set of 22 candidate high-resolution steps, generating sequences of six operations, and are compared to the current synthesis approaches. [source] An update on the first decade of the European centralized procedure: how many innovative drugs?BRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 5 2006Domenico Motola What is already known about this subject ,,We recently proposed an algorithm to assess the degree of therapeutic innovation of new therapeutic agents. It was based on the disease seriousness, the availability of previous treatments and the extent of the therapeutic effect, and was applied to all therapeutic agents approved by the EMEA in the period 1995,2003. ,,A low percentage (32%) of important therapeutic innovation was found. This figure may be an underestimate of the actual level of innovation, because common biotechnological products, such as recombinant human insulins, must follow the centralized procedure. What this study adds ,,Details for each agent, focusing on the comparison of the degree of therapeutic innovation between biotechnological and nonbiotechnological therapeutic agents approved by EMEA during the its first decade of activity (1995,2004). The underlying hypothesis was that the latter have a higher degree of innovation because they followed the centralized procedure on the assumption that they are innovative. ,,The percentage of important therapeutic innovation was low not only for biotechnological products (25%), as expected because they include many already known products such as insulins, but also for nonbiotechnological therapeutic agents (29%). Aims In a previous paper, we proposed an algorithm to assess the degree of therapeutic innovation of the agents approved by the European centralized procedure, which must be followed by biotechnological products and is optional for drugs claimed as innovative. A low overall degree of therapeutic innovation (about 30%) was found. This figure may be an underestimate of the actual level of innovation, because common biotechnological products, such as recombinant human insulins, must follow this procedure. To test the hypothesis that therapeutic innovation prevails among nonbiotechnological products, we evaluated separately the degree of therapeutic innovation of biotechnological vs. nonbiotechnological agents in the first decade of European Medicines Agency activity, also studying a possible time trend. Methods We assessed, for each drug: (i) the seriousness of the target disease, (ii) the availability of previous treatments, and (iii) the extent of therapeutic effect according to the previously proposed algorithm. Results Our analysis considered 251 medicinal products corresponding to 198 active substances, classified according to four main areas as therapeutic agents (88.9%), diagnostics (5.5%), vaccines (5.1%) and life-style drugs (0.5%). Among all therapeutic agents, 49 out of 176 agents (28%) were classified as having an important degree of therapeutic innovation. Fifteen out of 60 biotechnological therapeutic agents were considered important therapeutic innovations (25%), whereas this figure was 29% for nonbiotechnological agents. Conclusions Among active substances claimed as innovative by the manufacturers, only a minority deserve this definition according to our algorithm. [source] | ||||||||||