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Solvent Phase (solvent + phase)
Selected AbstractsRECOVERY OF SINAPIC ACID FROM A WASTE STREAM IN THE PROCESSING OF YELLOW MUSTARD PROTEIN ISOLATEJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2008N. PRAPAKORNWIRIYA ABSTRACT A large amount of waste permeates generated from the processing of yellow mustard protein was concentrated fivefold using a nanofilter with a molecular weight cut off of 1,000 Da, while approximately 74% of sinapic acid was retained. Sinapic acid was then released from sinapine, its esterified form, by an alkaline hydrolysis. The hydrolyzed solution was acidified to prevent oxidation of the sinapic acid and to precipitate the remaining proteins. Subsequently, sinapic acid and other phenolics were extracted by a two-stage extraction using a mixture of diethyl ether and ethyl acetate (1:1), 165-min extraction time and permeate-to-solvent ratio of 1:2. Approximately 95% of the sinapic acid in the acidified permeate was finally concentrated in the solvent phase. PRACTICAL APPLICATIONS This development has led to an economical process to recover phenolics and to treat effluent from a process of oilseed protein while reducing the use of water during the extraction of protein. A reduction of water usage makes the processing of oilseed protein isolate more economically attractive, and the recovered phenolics may find a use as a nutraceutical. The developed process is not only limited to the recovery of phenolics from mustard, but also applied for recovering phenolic acids, specifically sinapic acid, from waste water from membrane processing of protein from mustard and similar polyphenol-containing oilseeds. [source] Extractive bioconversion in a four-phase external-loop airlift bioreactorAICHE JOURNAL, Issue 7 2000Lidija Sajc The integration of biosynthesis and product separation can increase the productivity of immobilized plant cells in airlift bioreactors. Extractive bioconversion of anthraquinones was studied in an external-loop airlift bioreactor consisting of a riser, a downcomer, and two horizontal sections, while containing alginate-immobilized Frangula alnus cells, a continuous aqueous phase (nutrient solution), dispersed solvent phase (n-hexadecane or silicone oil), and gas bubbles. A simple mathematical model was developed to describe the cocurrent liquid-liquid extraction in the riser section of the bioreactor and to rationalize the measured product concentrations in the aqueous and solvent phase. The model equations were solved analytically in a dimensionless form and used to study the effects of flow conditions, solvent properties, product formation rate, droplet size, and contactor length on the extraction efficiency and product concentration profiles in the continuous and dispersed phase. [source] Effect of solvent concentration on the extraction kinetics and diffusivity of Cyclosporin A in the fungus Tolypocladium inflatumBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2007May Ly Abstract The kinetics of solid-liquid extraction and extraction yields of the immunosuppressant drug Cyclosporin A (CyA) from the mycelia of Tolypocladium inflatum were examined in this study. A 2 L stirred, baffled vessel was used to extract CyA from wet mycelia mass. Three different organic solvents were used, namely, methanol, acetone, and isopropanol at different concentrations in aqueous mixtures at room temperature. It was found that the best solvent was acetone at 50% v/v concentration achieving 100% extraction of CyA from the mycelia of T. inflatum. Although acetone proved to be the better solvent for CyA extraction, further studies were performed using methanol. A linear relationship was found between extraction yield of CyA and methanol concentration with 100% CyA extraction at 90% v/v methanol. The partition coefficients of CyA between the solid mycelia phase and the aqueous solvent phase were found to decrease exponentially with increasing methanol concentration. A liquid extraction model was developed based on the diffusion equation to correlate the kinetic data of CyA extraction from the solid mycelia of T. inflatum. Non-linear regression analysis of experimental data was used with the diffusion equation in order to calculate the effective diffusivities of CyA in the mycelia of T. inflatum. For all three organic solvents used, the effective diffusivities of CyA were found to be between 4.41,×,10,15 and 6.18,×,10,14 m2/s. This is the first time CyA effective diffusivities in T. inflatum are reported in the literature. Biotechnol. Bioeng. 2007;96: 67,79. © 2006 Wiley Periodicals, Inc. [source] Degradation of xenobiotics in a partitioning bioreactor in which the partitioning phase is a polymerBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2003Brian G. Amsden Abstract Two-phase partitioning bioreactors (TPPBs) are characterized by a cell-containing aqueous phase and a second immiscible phase that contains toxic and/or hydrophobic substrates that partition to the cells at subinhibitory levels in response to the metabolic demand of the organisms. To date, the delivery phase in TPPBs has been a hydrophobic solvent that traditionally needed to possess a variety of important properties including biocompatibility, nonbioavailability, low volatility, and low cost, among others. In the present work we have shown that the organic solvent phase can be replaced by inexpensive polymer beads that function in a similar fashion as organic solvents, delivering a toxic substrate to cells based on equilibrium considerations. Specifically, 3.4 mm diameter beads of poly(ethylene-co-vinyl acetate) (EVA) were used to reduce the aqueous concentration of phenol in a bioreactor from toxic levels ( ,2,000 mg/L) to subinhibitory levels (,750 mg/L), after which Pseudomonas putida ATCC 11172 was added to the system and allowed to consume the total phenol loading. Thus, the beads absorbed the toxic substrate and released it to the cells on demand. The EVA beads, which could be reused, were able to absorb 14 mg phenol/g EVA. This work has opened the possibility of using widely mixed cultures in TPPB systems without concern for degradation of the delivery material and without concern of contamination. © 2003 Wiley Periodicals. Biotechnol Bioeng84: 399,305, 2003. [source] Interactions between Brushlike Polyacrylic Acid Side Chains on a Polyacrylate Backbone in Dioxane,WaterCHEMPHYSCHEM, Issue 2 2005Fengjun Hua Dr. Abstract Densely grafted polyacrylic acids (d-PAAs) with overcrowded PAA side chains on the polyacrylate main chains were synthesized and characterized. Acryloyl poly(tert -butyl acrylate) macromonomer [M-P(tert- BA)] was prepared with a definite chain length (n=29) by atom-transfer radical polymerization (ATRP), then homopolymerization was carried out to produce densely grafted P(tert- BA)s with polyacrylate main chains of two different lengths (m=27 and 161). The two d-PAAs were obtained by hydrolyzing d-P(tert- BA)s in the presence of trifluoroacetic acid (TFA). The d-PAAs exhibit intermolecular and intramolecular hydrogen bonding between the carboxylic groups of PAA side chains in dioxane and pyridine; both were investigated using proton nuclear magnetic resonance (1H NMR) spectroscopy. The intermolecular hydrogen bonding was found to be dependent on polymer concentration, temperature, and water content. The intramolecular association between the PAA side chains was found to produce a contraction of the hydrodynamic volume of the d-PAA. Intermolecular hydrogen bonding produces aggregates, as demonstrated by dynamic light scattering (DLS). The clusters were found to shrink as the overall water concentration decreased, and this effect is tentatively explained by considering the gradient in chemical potential of water inside the clusters in comparison with the solvent phase. [source] Analyses of the partition coefficient, log P, using ab initio MO parameter and accessible surface area of solute moleculesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2004Hiroshi Chuman Abstract To analyze the log Psol/w values (sol: n -octanol or chloroform, w: water) in the framework of the molecular orbital (MO) procedure, we selected solute descriptors such as the solvation energy difference between aqueous and organic solvent phases and the "surface" area of solute molecules to which water molecules are accessible. The solvation energy of solute molecules in their minimum free-energy conformation was calculated using the ab initio self-consistent reaction field-MO method with the conductor-like screening model. The experimentally measured log Psol/w value of various solutes except for those of amphiprotics was shown to be analyzable reasonably well by the MO model with additional descriptors for the hydrogen-bonding patterns in the solute,solvent interactions. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:2681,2697, 2004 [source] | ||||||||||