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Extraction Conditions (extraction + condition)
Selected AbstractsMicrowave-assisted extraction of total bioactive saponin fraction from Gymnema sylvestre with reference to gymnemagenin: a potential biomarkerPHYTOCHEMICAL ANALYSIS, Issue 6 2009Vivekananda Mandal Abstract Objective , To develop a fast and ecofriendly microwave assisted extraction (MAE) technique for the effective and exhaustive extraction of gymnemagenin as an indicative biomarker for the quality control of Gymnema sylvestre. Methodology , Several extraction parameters such as microwave power, extraction time, solvent composition, pre-leaching time, loading ratio and extraction cycle were studied for the determination of the optimum extraction condition. Scanning electron micrographs were obtained to elucidate the mechanism of extraction Results , The final optimum extraction conditions as obtained from the study were: 40% microwave power, 6,min irradiation time, 85% v/v methanol as the extraction solvent, 15,min pre-leaching time and 25,:,1 (mL/g) as the solvent-to-material loading ratio. The proposed extraction technique produced a maximum yield of 4.3% w/w gymnemagenin in 6,min which was 1.3, 2.5 and 1.95 times more efficient than 6,h of heat reflux, 24,h of maceration and stirring extraction, respectively. A synergistic heat and mass transfer theory was also proposed to support the extraction mechanism Conclusion , Comparison with conventional extraction methods revealed that MAE could save considerable amounts of time and energy, whilst the reduction of volume of organic solvent consumed provides an ecofriendly feature. Copyright © 2009 John Wiley & Sons, Ltd. [source] Improved 2-DE of microorganisms after acidic extractionELECTROPHORESIS, Issue 8 2006Ben R. Herbert Professor Abstract 2-DE separations of protein extracts sometimes have problems with poor resolution and streaking. This problem is particularly apparent with microorganisms, most notably those with a large cell wall. Here we describe a novel, rapid protocol for the extraction of microorganisms in acidic conditions, leading to increased resolution and 2-D gel quality. The efficiency of the protocol is demonstrated with extracts of bacteria, Escherichia coli and Bacillus subtilis; fungus, Trichoderma harzianum and yeast, Saccharomyces cerevisiae. We also demonstrate using a membrane centrifugal filtration, that large acidic molecules in excess of 100,kDa, probably including cell wall material, are responsible for the separation difficulties. A range of acidic extraction conditions were investigated, and it was found that optimal extraction is achieved using an extraction solution acidified to pH,3 by 80,mM citric acid. These findings have significant implications for the proteomic study of many medically, agriculturally and environmentally significant microorganisms, as the cell walls of these organisms are often considerably more complex than many commonly studied laboratory strains. [source] Fluorinated ,-Diketones for the Extraction of Lanthanide Ions: Photophysical Properties and Hydration Numbers of Their EuIII ComplexesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2006Anne-Sophie Chauvin Abstract Tris(,-diketonato)europium(III) with a series of variably fluorinated ligands derived from 3,5-heptanedione were synthesised with the aim of determining their hydration state under extraction conditions. The number of coordinated water molecules was determined by measuring the lifetime of the Eu(5D0) excited level in water and deuterated water. The hydration gain (,q = q , q0) after shaking chloroform solutions during 10 min with 0.1 M NaClO4 aqueous solutions depends on the fluorination extent of the diketonates: fluorination of one methyl group leads to a decrease in ,q of ca. 0.5 unit, while fluorination of one ethyl group results in a decrease of ca. 1.3 units. Highly fluorinated complexes (i.e with hexafluoroacetylacetonate and related ligands) display a hydration number close to one while poorly fluorinated compounds (or nonfluorinated ones, such as the acetylacetonate complex) have a hydration state close to two. Photophysical properties of the EuIII ,-diketonates are also described and the synthesis of the fluorinated ,-diketones is re-investigated and discussed in details. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Effect of various extraction conditions on the phenolic contents of pomegranate seed oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2008Hajar Abbasi No abstracts. [source] Effect of various extraction conditions on the phenolic contents of pomegranate seed oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2008Hajar Abbasi Abstract Pomegranate seeds are byproducts of the pomegranate juice industry. Because of the presence of large amounts of certain pharmaceutical and nutraceutical components in the seeds, a proper extraction method to obtain these components is highly demanded in the food industry. In this study, the effect of different extraction methods on the total phenolic contents of the oil extracted from pomegranate seeds of the Malas variety from Shahreza, Iran, was investigated. Four different extraction methods including normal stirring, Soxhlet, microwave irradiation and ultrasonic irradiation using two types of organic solvents as well as a supercritical fluid extraction (SFE) method using CO2 as solvent were applied. The different organic solvents of this study did not indicate any significant differences in the total phenolic contents of the extracted oils, but the extracted oils from the various conditions of SFE indicated wide changes in the amount of phenolic compounds (7.8,72.1,mg/g). The total phenolic content of the extracted oil from one of the SFE runs was several times greater than those in the extracted oils using organic solvents. [source] Optimisation study of gum extraction from Basil seeds (Ocimum basilicum L.)INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2009Seyed M. A. Razavi Summary Basil seed (Ocimum basilicum L.) is cultivated in large quantities in different regions of Iran. This seed has reasonable amounts of gum with good functional properties which is comparable with commercial food hydrocolloids. A central composite rotatable design was applied to evaluate the effects of temperature, pH and water/seed ratio on the yield, apparent viscosity and protein content of water-extracted Basil seed gum. All of the variables significantly (P < 0.05) affected the extraction yield, whereas the effect of water/seed ratio on apparent viscosity and the effects of pH and water/seed ratio on protein content were not significant (P > 0.05). Numerical optimisation determined the optimum extraction conditions based on the highest yield and viscosity and the lowest protein content as being temperature 68.71 °C, pH 8.09 and water/seed ratio 65.98:1. Power law model well described non-Newtonian pseudoplastic behaviour of BSG. Flow behaviour index (n) and consistency index (K) of 1% crude and pure BSG samples were 0.306, 0.283 and 17.46, 20.22 Pa sn, respectively. [source] Cell removal with supercritical carbon dioxide for acellular artificial tissueJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 6 2008K. Sawada Abstract BACKGROUND: The objective of this work was to decellularize artificial tissue without using surfactant solutions. For this purpose, supercritical carbon dioxide was used as the extraction medium. RESULTS: Supercritical carbon dioxide containing a small amount of entrainer was a suitable medium to extract both cell nuclei and cell membranes from artificial tissue. Under gentle extraction conditions (15 MPa, 37 °C), cell nuclei were satisfactorily extracted from tissue within 1 h. In contrast, the efficiency of phospholipid removal depended strongly on the transfer rate of carbon dioxide in the interior of the tissue. Mechanical strength of tissue was not decreased even with prolonged treatment. CONCLUSION: Acellular artificial tissues could be prepared quickly by treatment with a carbon dioxide/entrainer system. The prepared acellular tissue could be obtained in absolutely dry condition. This is advantageous from the viewpoint of long-term preservation without putrefaction and contamination. Copyright © 2008 Society of Chemical Industry [source] ANALYSIS OF VARIABLES AND MODELING OF GEVUINA AVELLANA OIL EXTRACTION WITH ETHANOL NEAR AZEOTROPE CONDITIONSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2009DANIEL FRANCO ABSTRACT Oil extraction from Gevuina avellana Mol. (Chilean hazelnut) with ethanol, near the conditions of its azeotrope with water, was carried out in this work. The effects of solubility, liquid-to-solid ratio and moisture content of ethanol were studied using 92% ethanol, azeotropic (96%) and absolute ethanol (99.9%) as solvents. Water content had a high effect on oil solubility, which reached 140 g/L in 99.9% ethanol, whereas it was 40 g/L with azeotropic ethanol. Oil accounted for 93% of total extractable compounds with absolute ethanol. Kinetics studies of the extraction process were performed at 50C, giving as a result apparent diffusivity values near 10,11 m2/s, being the highest values obtained for ethanol 92% (7.5,16 × 10,11). It was also found that the higher the liquid-to-solid ratio, the higher the diffusivity. Simulation of four-stage countercurrent extraction with azeotropic ethanol yielded 23.5% oil extraction, whereas simulation of four-stage cross-flow extraction yielded 40.7%. Ethanol can be an alternative to batch cold pressing or hexane solvent extraction, for G. savellana seeds or meal processing. PRACTICAL APPLICATIONS The results presented in this paper are applicable for obtaining oil from oilseeds by extraction with ethanol. It includes relevant results for the optimization of extraction conditions and particularly those regarding liquid-to-solid ratio and percentage of water. Considering the more specific focus of this research, the results are applicable to obtaining Gevuina avellana oil by using an ethanol-based process, which will allow to avoid one of the cold-pressing process drawbacks: the high oil content of the meal, which is a factor limiting its lifetime. [source] Functional Properties of Improved Glycinin and ,-nglycinin FractionsJOURNAL OF FOOD SCIENCE, Issue 4 2004D. A. Rickert ABSTRACT: Glycinin and ,-conglycinin have unique functionality characteristics that contribute important properties in soy foods and soy ingredients. Limited functionality data have been published for glycinin and ,-conglycinin fractions produced in pilot-scale quantities. Protein extraction conditions were previously optimized for our pilotscale fractionation process to maximize protein solubilization and subsequent product recovery. Glycinin, ,-conglycinin, and intermediate (mixture of glycinin and ,-conglycinin) fractions were prepared using optimized-process (OP) extraction conditions (10:1 water-to-flake ratio, 45°C) and previous conditions termed Wu process (WP) (15:1, 20°C). Viscosity, solubility, gelling, foaming, emulsification capacity, and emulsification activity and stability of the fractionated proteins, and soy protein isolate (SPI) produced from the same defatted soy white flakes were compared to evaluate functional properties of these different protein fractions. Differential scanning calorimetry, sodium dodecylsulfate-polyacrylamide gel electrophoresis, and surface hydrophobicity data were used to interpret functionality differences. OP ,-conglycinin had more glycinin contamination than did the WP ,-conglycinin. OP and WP solubility profiles were each similar for respective glycinin and ,-conglycinin fractions. Emulsification activities and stabilities were higher for OP ,-conglycinin and OP intermediate fractions compared with respective WP fractions. ,-Conglycinin and SPI emulsification capacities (ECs) mirrored solubility profile, whereas glycinin ECs did not. OP glycinin had a higher foaming capacity than WP glycinin. OP and WP intermediate fraction apparent viscosities trended higher than those of other protein fractions. ,-Conglycinin dispersions at pH 3 and 7 produced firm gels at 80°C, whereas glycinin dispersions formed weaker gels at 99°C and did not gel at 80°C. [source] Extraction of Poppy Seed Oil Using Supercritical CO2JOURNAL OF FOOD SCIENCE, Issue 2 2003B. Bozan ABSTRACT: Extraction of poppy seed oil with supercritical carbon dioxide (SC-CO2) was performed and the effect of extraction conditions on oil solubility and yield as well as oil composition was evaluated. Within the temperature (50 to 70 °C) and pressure (21 to 55 MPa) ranges studied, 55 MPa/70 °C gave the highest oil solubility (24.1 mg oil/g CO2) and oil yield (38.7 g oil/100g seed). Fatty acid composition of the oil obtained with SC-CO2 at 55 MPa/70 °C was similar to that of petroleum ether-extracted oil (p > 0.05) with linoleic acid making up 69.0 to 73.7% of fatty acids. Tocol content of the SC-CO2 -extracted oils varied from 22.37 to 33.35 mg/100 g oil, which was higher than that of petroleum ether-extracted oil (15.28 mg/100 g oil). Poppy seed oil may have potential in the rapidly growing specialty oil market. [source] Automated stir plate (bar) sorptive extraction coupled to high-performance liquid chromatography for the determination of polycyclic aromatic hydrocarbonsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 14 2010Chunhe Yu Abstract Automated methods of PDMS/,-CD/divinylbenzene-coated stir plate sorptive extraction (SPSE) coupled to HPLC-fluorescence detector were reported for the first time. Three automation modes, static SPSE, circular flow SPSE and continuous flow SPSE, were evaluated and critically compared with stir bar sorptive extraction by using six polycyclic aromatic hydrocarbons as model analytes. It was found that the operable sample volume for circular flow SPSE and continuous flow SPSE was larger than that for static SPSE. Under the same extraction conditions, continuous flow SPSE exhibited the highest extraction efficiencies in all automated modes and manual stir bar sorptive extraction for the target compounds. Compared with the manual operation (approximately 5,10,min), automated SPSE required a relatively short time (117,180,s) to finish sampling, washing and sample loading. Besides being labor-saving and time-saving, automated SPSE has other advantages, such as no time limit and non-attended operation. The proposed continuous flow PDMS/,-CD/divinylbenzene-coated SPSE-HPLC-fluorescence detector was successfully applied to environmental water analysis. [source] Highly sensitive determination of tetrabromobisphenol A and bisphenol A in environmental water samples by solid-phase extraction and liquid chromatography-tandem mass spectrometryJOURNAL OF SEPARATION SCIENCE, JSS, Issue 11 2010Ru-Song Zhao Abstract Using bamboo-activated charcoal as SPE adsorbent, a novel SPE method was developed for the sensitive determination of tetrabromobisphenol A and bisphenol A in environmental water samples by rapid-resolution LC-ESI-MS/MS. Important parameters influencing extraction efficiency, including type of eluent, eluent volume, sample pH, volume and flow rate, were investigated and optimized. Under the optimal extraction conditions (eluent: 8,mL methanol, pH: 7; flow rate: 4,mL/min; sample volume: 100,mL), low LODs (0.01,0.02,ng/mL), good repeatability (6.2,8.3%) and wide linearity range (0.10,10,ng/mL) were obtained. Satisfied results were achieved when the proposed method was applied to determine the two target compounds in real-world environmental water samples with spiked recoveries over the range of 80.5,119.8%. All these facts indicate that trace determination of tetrabromobisphenol A and bisphenol A in real-world environmental water samples can be realized by bamboo-activated charcoal SPE-rapid resolution-LC-ESI-MS/MS. [source] The comparison of solid phase microextraction-GC and static headspace-GC for determination of solvent residues in vegetable oilsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 2 2008Magdalena Ligor Abstract The objective of these investigations has been the determination of volatile organic compounds including residue solvents present in vegetable oil samples. Some olive oil, rape oil, sunflower oil, soy-bean oil, pumpkin oil, grape oil, rice oil as well as hazel-nut oil samples were analysed. Among residue solvents the following compounds have been mentioned: acetone, n -hexane, benzene, and toluene. Some experiments for the solid phase microextraction (SPME),GC-flame ionisation detection (FID) were performed to examine extraction conditions such as fiber exposure time, temperature of extraction, and temperature of desorption. Various SPME fibers such as polydimethylsiloxane, Carboxen/polydimethylsiloxane and polydimethylsiloxane/divinylbenzene coatings were used for the isolation of tested compounds from vegetable oil samples. After optimisation of SPME, real vegetable oil samples were examined using SPME-GC/MS. Based on preliminary experiments the qualitative and quantitative analyses for the determination of acetone, n -hexane, benzene and toluene were performed by SPME-GC-FID and static head-space (SHS)-GC-FID methods. The regression coefficients for calibration curves for the examined compounds were R2 , 0.992. This shows that the used method is linear in the examined concentration range (0.005,0.119 mg/kg for SPME-GC-FID and 0.003,0.728 mg/kg for SHS-GC-FID). Chemical properties of analysed vegetable oils have been characterised by chemometric procedure (cluster analysis). [source] Methyl benzoate as a marker for the detection of mold in indoor building materialsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 18 2005Loay Wady Abstract A convenient analytical method to quantify volatile organic compounds (VOCs) emitted from various building materials has not been addressed yet. This work presents a new and rapid automated method using SPME combined with GC/MS. Methyl benzoate , as a metabolic biomarker for mold growth,was used to indicate VOCs and to determine and assess mold growth on damp samples. Gypsum board and wallboard paper were used as examples of common indoor building materials. Optimized extraction conditions were carried out manually, using a GC/flame ionization detector. Moldy samples were analyzed using an automated SPME-GC/MS analysis under optimized conditions. The amount of methyl benzoate emitted from the studied samples ranged from 32 to 46 ppb, where the density of the fungal biomass was found to be 8×104 cells/mL. A relationship between the amount of fungal biomass and the emitted concentration of methyl benzoate was found and assessed based upon cultured mold samples taken from indoor building sites. The analytical method shows promise for the compound methyl benzoate, which can easily be identified at low detection limits (LOD = 3 ppb) and good linearity (> 0.988), and its extraction and detection can be accomplished cleanly by current extraction techniques. Results suggest that this method with easy sample preparation can be used for quantitation and, of importance, minimal matrix effects are observed. [source] Characterization via liquid chromatography coupled to diode array detector and tandem mass spectrometry of supercritical fluid antioxidant extracts of Spirulina platensis microalgaJOURNAL OF SEPARATION SCIENCE, JSS, Issue 9-10 2005Jose A. Mendiola Abstract Spirulina platensis microalga has been extracted on a pilot scale plant using supercritical fluid extraction (SFE) under various extraction conditions. The extraction yield and the antioxidant activity of the extracts were evaluated in order to select those extracts with both the highest antioxidant capacity and a good extraction yield. These extracts were characterized using LC coupled to diode array detection (DAD) and LC coupled to mass spectrometry (MS) with two different interfaces, atmospheric pressure chemical ionization (APCI) and electrospray (ESI) which allowed us to perform tandem MS by using an ion trap analyzer. The best extraction conditions were as follows: CO2 with 10% of modifier (ethanol) as extraction solvent, 55°C (extraction temperature) and 220 bar (extraction pressure). Fractionation was achieved by cascade depressurization providing two extracts with different activity and chemical composition. Several compounds have been identified in the extracts, corresponding to different carotenoids previously identified in Spirulina platensis microalga along with chlorophyll a and some degradation products. Also, the structure of some phenolic compounds could be tentatively identified. The antioxidant activity of the extracts could be attributed to some of the above mentioned compounds. [source] Reducing glycerophosphocholine lipid matrix interference effects in biological fluid assays by using high-turbulence liquid chromatographyRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 21 2008Lihong Du Matrix interferences can severely affect quantitative assays of biological samples when electrospray ionization (ESI) is employed with liquid chromatography/tandem mass spectrometry (LC/MS/MS). A major source of matrix interferences for plasma sample analyses is the presence of glycerophosphocholine (GPCho) lipids. The efficiency of online high-turbulence liquid chromatography (HTLC) extraction for eliminating these lipids is evaluated and the interfering effects of endogenous lipids on human plasma assays are measured for pharmaceutical compounds having a wide variety of chemical properties. It is found that GPCho lipids, represented by 16:0, 18:1 and 18:0 LPC (lysophosphatidylcholine) and 16:0-18:2 PC, cause variations for hydrophobic compound analyses even when optimal online HTLC extraction conditions are employed. The efficiency for lipid removal depends on the organic content of the transfer solvent, but turbulent flow loading has no significant effect. Copyright © 2008 John Wiley & Sons, Ltd. [source] Decontamination of organochlorine pesticides in Radix Codonopsis by supercritical fluid extractions and determination by gas chromatographyBIOMEDICAL CHROMATOGRAPHY, Issue 9 2006Chunjie Zhao Abstract A method involving depuration of 12 organochlorine pesticides (OCPs) from Radix codonopsis was developed using supercritical fluid extraction (SFE). The pesticides investigated in the study included , -, , -, , - and , -benzene hexachloride, PCNB (pentachloro-nitrobenzene), PCA (pentachloroaniline), HEPT (heptachlor), MPCPS (methyl-pentachlorophenyl sulfide), pp,-DDE [1,1-dichloro-2, 2-bis(p -chlorophenyl) ethylene], op,-DDT [1,1,1-trichloro-2-(o -chlorophenyl)-2-(p -chlorophenyl)ethane], pp,-DDD [1,1-dichloro-2-2-bis(p -chlorophenyl)ethane] and pp,-DDT [1,1,1-trichloro-2,2-bis(p -chlorophenyl)ethane]. A series of experiments was conducted to optimize the final extraction conditions as follows: pure CO2, extraction pressure 15 MPa, extraction temperature 60°C, extraction time 20 min and flow rate 55 mL/h. A GC method with electron capture detection was employed for the determination of the OCPs in Radix codonopsis. An HPLC method was developed for the quantitative determination of active constituents. SFE was used to remove the organochlorine pesticide from Radix codonopsis. The results showed that at least 93.5% of the organochlorine pesticide residues in the herb sample were removed by SPE, while 95.0% of the active constituent marker (atractylenoide III) remained. Copyright © 2006 John Wiley & Sons, Ltd. [source] An automated fluorescence protein sequencer using 7-methylthio-4-(2,1,3-benzoxadiazolyl) isothiocyanate (MTBD-NCS) as an Edman reagentBIOMEDICAL CHROMATOGRAPHY, Issue 3 2002Natsuko Okiyama An automated fluorescence protein sequencer using 7-methylthio-5-(2,1,3-benzoxadiazolyl) isithiocyanate (MTBD-NCS), a fluorescent Edman reagent, is developed by the modification of a commercial protein sequencer. The generated MTBD-thiohydantoin amino acids fluoresced strongly, whereas the by-products such as MTBD-thiocarbamoyl amino acids and MTBD-carbamoly amino acids did not fluoresce. A few interfering peaks were observed in the chromatogram and amino acid sequence was easily determined. The coupling and cyclization/cleavage reaction conditions and extraction conditions of generated MTBD-thiazolinone amino acids were optimized using an autonalyzer. Finally, the sequence of a synthetic peptide (25,pmol), leucine-enkephalin-Thr-amide, was determined and up to six residues were successively analyzed. Copyright © 2002 John Wiley & Sons, Ltd. [source] Enhanced kinetic extraction of parvovirus B19 structural proteinsBIOTECHNOLOGY & BIOENGINEERING, Issue 3 2002Colleen Sico Abstract Recombinant structural proteins (VP1 and VP2) of the human parvovirus B19 have been expressed simultaneously using the baculovirus expression system to form virus-like particles (VLPs) that have potential use as vaccines. In this study, we report optimization of extraction conditions to recover these VLPs from cell paste. Under hypotonic conditions with neutral pH these VLPs were poorly extracted (up to 3% extraction). Addition of reducing agents, detergents, salts, and sonication did not improve the extractability. While screening for conditions to improve the extractability of the VLPs, we discovered that a combination of higher pH and elevated processing temperature significantly increased the extraction. Whereas increasing pH alone increased extractability from 3% to 6% (pH increased from 8.0 to 9.5), the effect of elevated temperature was much more substantial. At 50°C, we observed the extraction to be more than fivefold higher than that at room temperature (up to 25% extracted at pH 9.0). The kinetics of extraction at elevated temperatures showed a rapid initial rate of extraction (on the order of minutes) followed by a plateau. In addition, we compared the extraction of VP1 expressed alone. VP1 expressed alone is incapable of forming VLPs. We observed that non-VLP VP1 was easily extractable (up to 60% extracted) under conditions in which the VP1 + VP2 VLPs were not extractable. From these studies we conclude that parvovirus B19 structural proteins expressed to form VLPs have a hindered extractability as compared with non-VLP protein. This hindrance to extraction can be significantly reduced by processing at elevated temperatures and an increased pH, possibly due to the enhanced rates of solubilization and diffusion. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng80: 250,256, 2002. [source] Fractionation of transgenic corn seed by dry and wet milling to recover recombinant collagen-related proteinsBIOTECHNOLOGY PROGRESS, Issue 5 2009Cheng Zhang Abstract Corn continues to be considered an attractive transgenic host for producing recombinant therapeutic and industrial proteins because of its potential for producing recombinant proteins at large volume and low cost as coproducts of corn seed-based biorefining. Efforts to reduce production costs have been primarily devoted to increasing accumulation level, optimizing protein extraction conditions, and simplifying the purification. In the present work, we evaluated two grain fractionation methods, dry milling and wet milling, to enrich two recombinant collagen-related proteins; thereby, reducing the amount and type of corn-derived impurities in subsequent protein extraction and purification steps. The two proteins were a full-length human recombinant collagen type I alpha 1(rCI,1) chain with telopeptides and peptide foldon to effect triple helix formation and a 44-kDa rCI,1 fragment. For each, ,60% of the rCI,1s in the seed was recovered in the dry-milled germ-rich fractions making up ca. 25% of the total kernel mass. For wet milling, ,60% of each was recovered in three fractions accounting for 20,25% of the total kernel mass. The rCI,1s in the dry-milled germ-rich fractions were enriched three to six times compared with the whole corn kernel, whereas the rCI,1s were enriched 4,10 times in selected wet-milled fractions. The recovered starch from wet milling was almost free of rCI,1. Therefore, it was possible to generate rCI,1-enriched fractions by both dry and wet milling along with rCI,1-free starch using wet milling. Because of its simplicity, the dry milling procedure could be accomplished on-farm thus minimizing the risk of inadvertent release of viable transgenic seeds. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] | |||||||||||||