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K. S. M. S. Raghavarao - One of the best experts on this subject based on the ideXlab platform.

  • Recent Developments in the Downstream Processing of Phycobiliproteins from Algae: A Review
    Current Biochemical Engineering, 2021
    Co-Authors: Ayekpam Chandralekha Devi, G. K. Hamsavi, Simran Sahota, Rochak Mittal, Hrishikesh A. Tavanandi, K. S. M. S. Raghavarao
    Abstract:

    Abstract: Algae (both micro and macro) have gained huge attention in the recent past for their high commercial value products. They are the source of various biomolecules of commercial applications ranging from nutraceuticals to fuels. Phycobiliproteins are one such high value low volume compounds which are mainly obtained from micro and macro algae. In order to tap the bioresource, a significant amount of work has been carried out for large scale production of algal biomass. However, work on Downstream Processing aspects of phycobiliproteins (PBPs) from algae is scarce, especially in case of macroalgae. There are several difficulties in cell wall disruption of both micro and macro algae because of their cell wall structure and compositions. At the same time, there are several challenges in the purification of phycobiliproteins. The current review article focuses on the recent developments in Downstream Processing of phycobiliproteins (mainly phycocyanins and phycoerythrins) from micro and macroalgae. The current status, the recent advancements and potential technologies (that are under development) are summarised in this review article besides providing future directions for the present research area.

  • Aqueous Two-phase Extraction in Downstream Processing
    Current Biochemical Engineering, 2015
    Co-Authors: M. C. Madhusudhan, N. Amrutha, Anupama Rani, K. S. M. S. Raghavarao
    Abstract:

    Aqueous two-phase extraction has been effectively used for the separation and purification of several biological molecules. The main advantages of aqueous two-phase extraction are biocompatibility, scope for continuous operation, process integration and ease of scale up. In Downstream Processing, aqueous two-phase extraction has found its applications in extraction, purification and concentration of various biomolecules. In this review, some of the applications of aqueous two-phase systemsemployed in Downstream Processing besides some basic aspects and a few case studies are presented. Some of the recent developments with regard to aqueous two-phase extraction are reviewed and the future prospects are also briefly discussed. - See more at: http://www.eurekaselect.com/128768/article#sthash.IPuCODUA.dpuf

  • Reverse micellar extraction for Downstream Processing of proteins/enzymes.
    Advances in biochemical engineering biotechnology, 2002
    Co-Authors: S. Hari Krishna, K. S. M. S. Raghavarao, N. D. Srinivas, N. G. Karanth
    Abstract:

    New developments in the area of Downstream Processing are, hopefully, to fulfill the promises of modern biotechnology. The traditional separation processes such as chromatography or electrophoresis can become prohibitively expensive unless the product is of high value. Hence, there is a need to develop efficient and cost-effective Downstream Processing methods. Reverse micellar extraction is one such potential and a promising liquid-liquid extraction technique, which has received immense attention for isolation and purification of proteins/enzymes in the recent times. This technique is easy to scale-up and offers continuous operation. This review, besides briefly considering important physico-chemical and biological aspects, highlights the engineering aspects including mass transfer, mathematical modeling, and technology development. It also discusses recent developments in reverse micellar extraction such as affinity based separations, enzymatic reactions in reverse micelles coupled with membrane processes, reverse micellar extraction in hollow fibers, etc. Special emphasis has been given to some recent applications of this technique.

  • reverse micellar extraction for Downstream Processing of proteins enzymes
    Advances in Biochemical Engineering \ Biotechnology, 2002
    Co-Authors: Hari S Krishna, K. S. M. S. Raghavarao, N. D. Srinivas, N. G. Karanth
    Abstract:

    New developments in the area of Downstream Processing are, hopefully, to fulfill the promises of modern biotechnology. The traditional separation processes such as chromatography or electrophoresis can become prohibitively expensive unless the product is of high value. Hence, there is a need to develop efficient and cost-effective Downstream Processing methods. Reverse micellar extraction is one such potential and a promising liquid-liquid extraction technique, which has received immense attention for isolation and purification of proteins/enzymes in the recent times. This technique is easy to scale-up and offers continuous operation. This review, besides briefly considering important physico-chemical and biological aspects, highlights the engineering aspects including mass transfer, mathematical modeling, and technology development. It also discusses recent developments in reverse micellar extraction such as affinity based separations, enzymatic reactions in reverse micelles coupled with membrane processes, reverse micellar extraction in hollow fibers, etc. Special emphasis has been given to some recent applications of this technique.

  • Aqueous two phase extraction for Downstream Processing of enzymes/proteins.
    Advances in Applied Microbiology, 1995
    Co-Authors: K. S. M. S. Raghavarao, Navin K. Rastogi, M.k. Gowthaman, N. G. Karanth
    Abstract:

    Publisher Summary This chapter discusses aqueous two-phase extraction (ATPE) for Downstream Processing of enzymes or proteins. Downstream Processing in many fermentation processes accounts for a large share of the total cost. The ATPE appears to be a promising technique for efficient Downstream Processing and some successful applications of ATPE on large/industrial scale have been demonstrated. In order to develop effective Downstream Processing methods employing ATPSs, an interdisciplinary effort involving a combination of microbiological, biochemical, and engineering aspects is very essential. In addition, enough attention has been paid to microbiological and biochemical aspects. Mathematical modeling, which is highlighted in this chapter, is of immense use in predicting the protein enzyme partitioning without the measurement of an inordinately large number of parameters. Although, in principle, ATPE offers the advantage of easy adaptation of the extraction equipment used in the chemical or pharmaceutical industry to achieve efficient extraction, the drop dynamics and mass transfer aspects of this contacting equipment should be studied in detail employing various ATPSs and real systems involving the actual fermentation broths. Even if some of these aspects are addressed in greater depth by future researchers, the objective of this chapter can be considered fulfilled in view of the recognized scientific and industrial potential of ATPE.

Julia Inés Fariña - One of the best experts on this subject based on the ideXlab platform.

  • Microbial production of scleroglucan and Downstream Processing.
    Frontiers in Microbiology, 2015
    Co-Authors: Natalia A. Castillo, Alejandra Leonor Valdez, Julia Inés Fariña
    Abstract:

    Synthetic petroleum-based polymers and natural plant polymers have the disadvantage of restricted sources, in addition to the non-biodegradability of the former ones. In contrast, eco-sustainable microbial polysaccharides, of low-cost and standardized production, represent an alternative to address this situation. With a strong global market, they attracted worldwide attention because of their novel and unique physico-chemical properties as well as varied industrial applications, and many of them are promptly becoming economically competitive. Scleroglucan, a beta-1,3-beta-1,6-glucan secreted by Sclerotium fungi, exhibits high potential for commercialization and may show different branching frequency, side-chain length and/or molecular weight depending on the producing strain or culture conditions. Water-solubility, viscosifying ability and wide stability over temperature, pH and salinity make scleroglucan useful for different biotechnological (enhanced oil recovery, food additives, drug delivery, cosmetic and pharmaceutical products, biocompatible materials, etc.), and biomedical (immunoceutical, antitumor, etc.) applications. It can be copiously produced at bioreactor scale under standardized conditions, where a high EPS concentration normally governs the process optimization. Operative and nutritional conditions, as well as the incidence of scleroglucan Downstream Processing will be discussed in this chapter. The relevance of using standardized inocula from selected strains and experiences concerning the intricate scleroglucan scaling-up will be also herein outlined.

  • Scleroglucan compatibility with thickeners, alcohols and polyalcohols and Downstream Processing implications.
    Carbohydrate Polymers, 2012
    Co-Authors: Silvana Carolina Viñarta, Lucía I. C. De Figueroa, Mariana M. Yossen, Jorge Ruben Vega, Julia Inés Fariña
    Abstract:

    Abstract Thickening capacity and compatibility of scleroglucan with commercial thickeners (corn starch, gum arabic, carboxymethylcellulose, gelatin, xanthan and pectin), glycols (ethylene glycol and polyethylene glycol), alcohols (methanol, ethanol, 1-propanol and isopropanol) and polyalcohols (sorbitol, xylitol and mannitol) was explored. Exopolysaccharides (EPSs) from Sclerotium rolfsii ATCC 201126 and a commercial scleroglucan were compared. Compatibility and synergism were evaluated taking into account rheology, pH and sensory properties of different thickener/scleroglucan mixtures in comparison with pure solutions. S. rolfsii ATCC 201126 EPSs induced or increased pseudoplastic behaviour with a better performance than commercial scleroglucan, showing compatibility and synergy particularly with corn starch, xanthan, pectin and carboxymethylcellulose. Compatibility and a slight synergistic behaviour were also observed with 30% (w/v) ethylene glycol whereas mixtures with polyethylene glycol (PEG) precipitated. Scleroglucan was compatible with polyalcohols, whilst lower alcohols led to scleroglucan precipitation at 20% (v/v) and above. PEG-based scleroglucan Downstream Processing was compared to the usual alcohol precipitation. Downstream processed EPSi (with isopropanol) and EPS-p (with PEG) were evaluated on their yield, purity, rheological properties and visual aspect pointing to alcohol Downstream Processing as the best methodology, whilst PEG recovery would be unsuitable. The highest purified EPSi attained a recovery yield of ∼23%, similar to ethanol purification, with a high degree of purity (88%, w/w vs . EPS-p, 8%, w/w) and exhibited optimal rheological properties, water solubility and appearance. With a narrower molecular weight distribution ( M w , 2.66 × 10 6  g/mol) and a radius of gyration ( R w , 245 nm) slightly lower than ethanol-purified EPSs, isopropanol Downstream Processing showed to be a proper methodology for obtaining a refined-grade scleroglucan.

Jurgen Hubbuch - One of the best experts on this subject based on the ideXlab platform.

  • advances in Downstream Processing of biologics spectroscopy an emerging process analytical technology
    Journal of Chromatography A, 2017
    Co-Authors: Matthias Rudt, Till Briskot, Jurgen Hubbuch
    Abstract:

    Abstract Process analytical technologies (PAT) for the manufacturing of biologics have drawn increased interest in the last decade. Besides being encouraged by the Food and Drug Administration's (FDA's) PAT initiative, PAT promises to improve process understanding, reduce overall production costs and help to implement continuous manufacturing. This article focuses on spectroscopic tools for PAT in Downstream Processing (DSP). Recent advances and future perspectives will be reviewed. In order to exploit the full potential of gathered data, chemometric tools are widely used for the evaluation of complex spectroscopic information. Thus, an introduction into the field will be given.

  • Advances in Downstream Processing of biologics – Spectroscopy: An emerging process analytical technology
    Journal of Chromatography A, 2017
    Co-Authors: Matthias Rudt, Till Briskot, Jurgen Hubbuch
    Abstract:

    Process analytical technologies (PAT) for the manufacturing of biologics have drawn increased interest in the last decade. Besides being encouraged by the Food and Drug Administration's (FDA's) PAT initiative, PAT promises to improve process understanding, reduce overall production costs and help to implement continuous manufacturing. This article focuses on spectroscopic tools for PAT in Downstream Processing (DSP). Recent advances and future perspectives will be reviewed. In order to exploit the full potential of gathered data, chemometric tools are widely used for the evaluation of complex spectroscopic information. Thus, an introduction into the field will be given.

Tim Tressel - One of the best experts on this subject based on the ideXlab platform.

  • viral clearance using disposable systems in monoclonal antibody commercial Downstream Processing
    Biotechnology and Bioengineering, 2008
    Co-Authors: Joe X Zhou, Feli Solamo, Tony Hong, Michael Sheare, Tim Tressel
    Abstract:

    Once highly selective protein A affinity is chosen for robust mAb Downstream Processing, the major role of polishing steps is to remove product related impurities, trace amounts of host cell proteins, DNA/RNA, and potential viral contaminants. Disposable systems can act as powerful options either to replace or in addition to polishing column chromatography to ensure product purity and excellent viral clearance power for patients' safety. In this presentation, the implementation of three disposable systems such as depth filtration, membrane chromatography, and nanometer filtration technology in a commercial process are introduced. The data set of viral clearance with these systems is presented. Application advantages and disadvantages including cost analysis are further discussed. Biotechnol. Bioeng. 2008;100: 488–496. © 2008 Wiley Periodicals, Inc.

  • viral clearance using disposable systems in monoclonal antibody commercial Downstream Processing
    Biotechnology and Bioengineering, 2008
    Co-Authors: Joe X Zhou, Feli Solamo, Tony Hong, Michael Shearer, Tim Tressel
    Abstract:

    Once highly selective protein A affinity is chosen for robust mAb Downstream Processing, the major role of polishing steps is to remove product related impurities, trace amounts of host cell proteins, DNA/RNA, and potential viral contaminants. Disposable systems can act as powerful options either to replace or in addition to polishing column chromatography to ensure product purity and excellent viral clearance power for patients' safety. In this presentation, the implementation of three disposable systems such as depth filtration, membrane chromatography, and nanometer filtration technology in a commercial process are introduced. The data set of viral clearance with these systems is presented. Application advantages and disadvantages including cost analysis are further discussed.

Pascal M W Drake - One of the best experts on this subject based on the ideXlab platform.

  • rhizosecretion improves the production of cyanovirin n in nicotiana tabacum through simplified Downstream Processing
    Biotechnology Journal, 2016
    Co-Authors: Luisa Madeira, Tim H Szeto, Julian K C, Pascal M W Drake
    Abstract:

    Rhizosecretion has many advantages for the production of recombinant pharmaceuticals, notably facile Downstream Processing from hydroponic medium. The aim of this study was to increase yields of the HIV microbicide candidate, Cyanovirin-N (CV-N), obtained using this production platform and to develop a simplified methodology for its Downstream Processing from hydroponic medium. Placing hydroponic cultures on an orbital shaker more than doubled the concentration of CV-N in the hydroponic medium compared to plants which remained stationary, reaching a maximum of approximately 20μg/ml in one week, which is more than 3 times higher than previously reported yields. The protein composition of the hydroponic medium, the rhizosecretome, was characterised in plants cultured with or without the plant growth regulator alpha-napthaleneacetic acid by LC-ESI-MS/MS, and CV-N was the most abundant protein. The issue of large volumes in the rhizosecretion system was addressed by using ion exchange chromatography to concentrate CV-N and partially remove impurities. The semi-purified CV-N was demonstrated to bind to HIV gp120 in an ELISA and to neutralise HIVBa-L with an IC50 of 6nM in a cell-based assay. Rhizosecretion is therefore a practicable and inexpensive method for the production of functional CV-N.

  • Rhizosecretion improves the production of Cyanovirin‐N in Nicotiana tabacum through simplified Downstream Processing
    Biotechnology Journal, 2016
    Co-Authors: Luisa De Moraes Madeira, Tim H Szeto, Pascal M W Drake
    Abstract:

    Rhizosecretion has many advantages for the production of recombinant pharmaceuticals, notably facile Downstream Processing from hydroponic medium. The aim of this study was to increase yields of the HIV microbicide candidate, Cyanovirin-N (CV-N), obtained using this production platform and to develop a simplified methodology for its Downstream Processing from hydroponic medium. Placing hydroponic cultures on an orbital shaker more than doubled the concentration of CV-N in the hydroponic medium compared to plants which remained stationary, reaching a maximum of approximately 20μg/ml in one week, which is more than 3 times higher than previously reported yields. The protein composition of the hydroponic medium, the rhizosecretome, was characterised in plants cultured with or without the plant growth regulator alpha-napthaleneacetic acid by LC-ESI-MS/MS, and CV-N was the most abundant protein. The issue of large volumes in the rhizosecretion system was addressed by using ion exchange chromatography to concentrate CV-N and partially remove impurities. The semi-purified CV-N was demonstrated to bind to HIV gp120 in an ELISA and to neutralise HIVBa-L with an IC50 of 6nM in a cell-based assay. Rhizosecretion is therefore a practicable and inexpensive method for the production of functional CV-N.