Ethanol Precipitation Step Research Articles

Ethanol treatment for sterilization, concentration, and stabilization of a biodegradable plastic-degrading enzyme from Pseudozyma antarctica culture supernatant.

Biodegradable plastics must be sufficiently stable to maintain functionality during use but need to be able to degrade rapidly after use. We previously reported that treatment with an enzyme named PaE, secreted by the basidiomycete yeast Pseudozyma antarctica can speed up this degradation. To facilitate the production of large quantities of PaE, here, we aimed to elucidate the optimal conditions of ethanol treatment for sterilization of the culture supernatant and for concentration and stabilization of PaE. The results showed that Pseudozyma antarctica completely lost its proliferating ability when incubated in ≥20% (v/v) ethanol. When the ethanol concentration was raised to 90% (v/v), PaE formed a precipitate; however, its activity was restored completely when the precipitate was dissolved in water. To reduce ethanol use, PaE was successfully concentrated and recovered by sequential ammonium sulfate precipitation and ethanol precipitation steps. Over 90% of the activity in the original culture supernatant was recovered and the specific activity was increased 3.4-fold. By preparing the enzyme solution at a final concentration of 20% (v/v) ethanol, about 60% of the initial activity was maintained at ambient temperature for over 6 months without growth of microbes. We conclude that ethanol treatment is effective for sterilization, concentration, and stabilization of PaE, and that concentrating PaE by sequential ammonium sulfate precipitation and ethanol precipitation substantially increases the PaE purity and decreases ethanol use.

Pharmacokinetic Studies of Antisense Oligonucleotides Using MALDI-TOF Mass Spectrometry.

Cardiac diseases are the most frequent causes of death in industrialized countries. Pathological remodeling of the heart muscle is caused by several etiologies such as prolonged hypertension or injuries that can lead to myocardial infarction and in serious cases also the death of the patient. The micro-RNA miR-132 has been identified as a master-switch in the development of cardiac hypertrophy and adverse remodeling. In this study, MALDI-TOF mass spectrometry (MS) was utilized to establish a robust and fast method to sensitively detect and accurately quantify anti-microRNA (antimiR) oligonucleotides in blood plasma. An antimiR oligonucleotide isolation protocol containing an ethanol precipitation step with glycogen as oligonucleotide carrier as well as a robust and reproducible MS-analysis procedure has been established. Proteinase K treatment was crucial for releasing antimiR oligonucleotides from plasma- as well as cellular proteins and reducing background derived from biological matrices. AntimiR oligonucleotide detection was achieved from samples of studies in different animal models such as mouse and pig where locked nucleic acids-(LNA)-modified antimiR oligonucleotides have been used to generate pharmacokinetic data.

A scalable, efficient, and safe method to prepare high quality DNA from mycobacteria and other challenging cells

The rapid development in sequencing technology is creating an increase in demand for largely intact DNA as starting material as very long strands of DNA are sequenced directly to generate reads that are thousands of bases long. Organisms with thick cell walls are difficult to lyse, often impacting both DNA recovery and quality. Consequently, most mycobacterial DNA extraction methods require bead-beating steps or toxic chemicals. Here we present an updated method that yields abundant, high quality genomic DNA from M. tuberculosis and diverse nontuberculous mycobacterial (NTM) species, in addition to complex biological communities from a variety of sources. This method eliminates the time-consuming phenol and chloroform extraction and ethanol precipitation steps, and high quality DNA from up to 96 samples can be extracted in about 2–3 h of hands-on time. This DNA is suitable for long and short read sequencing technologies as well as PCR and qPCR amplification.

A rapid and low-cost method for genomic DNA extraction from the cyanobacterium Synechocystis.

A two-step method is reported for preparation of genomic DNA from the model cyanobacterium Synechocystis that can be performed with minimal equipment and reagents in about an hour. High yields of genetic material can be obtained (200–450 ng/μl) with reasonable purity. A further ethanol precipitation step can be included but is not necessary if template is simply required for polymerase chain reaction (PCR) or digestion. This new protocol is helpful for amplification of genes of interest in early-stage research projects and for low throughput screening of transformants. It is more reliable than colony PCR of Synechocystis cultures, and less involved and cheaper than existing clean-DNA preparation methods. It represents an unusually simple and reliable extraction protocol for the growing body of research making use of this cyanobacterium.

A simple, fast, and inexpensive CTAB-PVP-silica based method for genomic DNA isolation from single, small insect larvae and pupae.

In this study, we report a modified CTAB-PVP method combined with silicon dioxide (silica) treatment for the extraction of high quality genomic DNA from a single larva or pupa. This method efficiently obtains DNA from small specimens, which is difficult and challenging because of the small amount of starting tissue. Maceration with liquid nitrogen, phenol treatment, and the ethanol precipitation step are eliminated using this methodology. The A260/A280 absorbance ratios of the isolated DNA were approximately 1.8, suggesting that the DNA is pure and can be used for further molecular analysis. The quality of the isolated DNA permits molecular applications and represents a fast, cheap, and effective alternative method for laboratories with low budgets.

Development of an intravenous immunoglobulin with improved safety and functional activity

The development and properties of a liquid intravenous immunoglobulin (Gammaplex®), of high purity, stability and functional activity, is described. Virus and TSE reduction by specific steps in the process were evaluated by spiking studies using small-scale models. The removal of procoagulant activity was determined using immunochemical and functional activity assays. Neutralisation and opsonic activity were used to demonstrate the functional activity of the IgG. The final low pH formulated product was stable at room temperature and was of high purity and functional activity. Three dedicated virus inactivation steps, i.e. solvent detergent, low pH and virus filtration, were shown to be effective. When combined with the B + I ethanol precipitation step, this gave a total reduction of >21 to >24 log for the enveloped and >10 to >13 log for the non-enveloped viruses tested. Several steps in the process were shown to contribute to TSE removal using scrapie. Potential procoagulant activity including Factor XI/XIa, was reduced to very low/undetectable levels in the final product. A new high purity liquid IVIG product has been developed, of high purity and good functional activity and stability. The process includes various steps for the removal of pathogens and procoagulant activity.

Purification of equine chorionic gonadotropin (eCG) using magnetic ion exchange adsorbents in combination with high-gradient magnetic separation.

Current purification of the glycoprotein equine chorionic gonadotropin (eCG) from horse serum includes consecutive precipitation steps beginning with metaphosphoric acid pH fractionation, two ethanol precipitation steps, and dialysis followed by a numerous of fixed-bed chromatography steps up to the specific activity required. A promising procedure for a more economic purification procedure represents a simplified precipitation process requiring only onethird of the solvent, followed by the usage of magnetic ion exchange adsorbents employed together with a newly designed 'rotor-stator' type High Gradient Magnetic Fishing (HGMF) system for large-scale application, currently up to 100 g of magnetic adsorbents. Initially, the separation process design was optimized for binding and elution conditions for the target protein in mL scale. Subsequently, the magnetic filter for particle separation was characterized. Based on these results, a purification process for eCG was designed consisting of (i) pretreatment of the horse serum; (ii) binding of the target protein to magnetic ion exchange adsorbents in a batch reactor; (iii) recovery of loaded functionalized adsorbents from the pretreated solution using HGMF; (iv) washing of loaded adsorbents to remove unbound proteins; (v) elution of the target protein. Finally, the complete HGMF process was automated and conducted with either multiple single-cycles or multicycle operation of four sequential cycles, using batches of pretreated serum of up to 20 L. eCG purification with yields of approximately 53% from single HGMF cycles and up to 80% from multicycle experiments were reached, with purification and concentration factors of around 2,500 and 6.7, respectively.

New approaches for manufacturing plasma derivatives

Plasma fractionation is the large‐scale production process used to prepare an important class of protein products that are the only potential therapeutic options to treat, manage or prevent life‐threatening conditions resulting from immunological disorders, congenital plasma protein deficiencies, infections and trauma. The main plasma products include immunoglobulin G (IgG), coagulation factors, fibrinogen and albumin. The core plasma fractionation process, based on sequential ethanol precipitation steps, was developed in the 1940s. It has evolved over the years through implementation of chromatographic protein purification steps, viral safety treatments and automation into a complex biotechnological process. Industrial plasma fractionation is nowadays well mastered and scientifically understood in industrialized countries; product quality and safety benefit from the mature regulations overseeing the collection of plasma and licensing of therapeutic biologicals. Several emerging countries, interested in producing plasma products from local plasma resources to increase product supplies, have considered building fractionation plants. However, the complexities of the current plasma fractionation technology and its validation constitute a substantial barrier to entry into the field. Changes in plasma product drivers in industrialized countries have raised interest in novel, easily scalable plasma fractionation technologies capable of enhancing certain aspects, such as IgG recovery. Novel plasma fractionation approaches rely (1) on multiple chromatographic steps to capture target proteins in sequence, (2) membranes and differential electric potentials to partition proteins or (3) aqueous two‐phase system. A ‘mini‐pool’ method of fractionation and viral inactivation using disposable devices is being developed to fill in quality gaps between crude blood components and commercial products.

Production and Purification of Equine Chorionic Gonadotropin Hormone Using Polyclonal Antibody

Background: Equine chorionic gonadotropin (eCG) is commonly used in association with a progestagen treatment to synchronize estrus of goats and ewes during breeding and non-breeding seasons. Classical purification of the eCG from serum includes pH fractionation with metaphosphoric acid two ethanol precipitation steps as well as dialysis followed by fixed-bed chromatography. Objectives: The aim of the current study was to develop an accurate and fast method for production and purification of eCG using polyoclonal antibody assay. Materials and Methods: The blood samples (300 ml) were taken from jugular vein of 17 mares on days 50, 70 and 90 of pregnancy. Plasma of the samples was siphoned and phenol solution has been added to the plasma and stored in the refrigerator until eCG extraction. To prepare polyoclonal antibody against eCG, four male rabbits, about 4-months-old and 2-kg weights, were chosen. A basic immunization was done by injecting 25 IU of eCG to the rabbits. Ouchterlony assay or double immunodiffusion test was used to assess the immunization and the titer of antiserum against eCG. eCG has been purified from the plasma via Solid-Phase Extraction (SPE) method. Results: Results based on agarose-gel double immunodiffusion test showed that rabbits have been completely immunized. SDS-PAGE analysis showed purified eCG is extracted without any significant contamination. Conclusions: The extraction of eCG with polyclonal antibody using SPE method and production of anti- eCG antiserum in rabbits is suitable and may be a cost effective method for large scale production of eCG and anti- eCG antiserum in Iran.

Fast protocol for extraction of DNA from Prosopis spp leaves (plant adapted to arid environment) without liquid nitrogen

The extraction of high-quality genomic DNA from Prosopis spp for polymerase chain reaction (PCR) amplification is complicated, owing to the presence of a high percentage of secondary metabolites that bind to or co-precipitate with nucleic acids. In the present study, we report a modified sodium dodecyl sulfate/phenol protocol that eliminates the use of liquid nitrogen in the maceration process, β-mercaptoethanol in the buffer extraction, and the ethanol precipitation step. The A₂₆₀/A₂₈₀ absorbance ratios of the isolated DNA were approximately 2.0 to 1.9, suggesting that the DNA fraction was pure and can be used for further PCR analysis. The DNA isolated by this protocol is of sufficient quality for molecular applications; this technique could be applied to other organisms that have similar substances that hinder DNA extraction. Finally, this proposal represents an alternative fast, cheap, and effective method for the isolation of genomic DNA from fresh leaves of Prosopis spp, even in low-technology laboratories.

Methodology A rapid and inexpensive method for isolation of total DNA from Trichoderma spp (Hypocreaceae)

Extraction of high-quality genomic DNA for PCR amplification from filamentous fungi is difficult because of the complex cell wall and the high concentrations of polysaccharides and other secondary metabolites that bind to or co-precipitate with nucleic acids. We developed a modified sodium dodecyl sulfate/phenol protocol, without maceration in liquid nitrogen and without a final ethanol precipitation step. The A(260/280) absorbance ratios of isolated DNA were approximately 1.7-1.9, demonstrating that the DNA fraction is pure and can be used for analysis. Additionally, the A(260/230) values were higher than 1.6, demonstrating negligible contamination by polysaccharides. The DNA isolated by this protocol is of sufficient quality for molecular applications; this technique could be applied to other organisms that have similar substances that hinder DNA extraction. The main advantages of the method are that the mycelium is directly recovered from culture medium and it does not require the use of expensive and specialized equipment.

Isolation and Purification of Polysaccharides with Anti-tumor Activity from Pholiota adiposa (Batsch) P. Kumm. (Higher Basidiomycetes)

Pholiota adiposa is a mushroom with excellent medicinal and nutritional properties. After culture in fermentation medium, Ph. Adiposa mycelia were filtered, lyophilized, and powdered. A crude polysaccharide (PAP) of Ph. Adiposa was prepared from the mycelial powder with hot water, centrifuged, and the resulting supernatant lyophilized. PAP was fractionated by 30%, 60%, and 80% ethanol precipitation steps to yield PAP30, PAP60, and PAP80. Subsequently PAP30-1 and PAP30-2, PAP60-1 and PAP60-2, and PAP80-1 and PAP80-2 were isolated from PAP30, PAP60, and PAP80, respectively, by ion-exchange chromatography on a DEAE-Sepharose column. Polysaccharide content increased from 43.8% in PAP to 50.54%~73.19% in PAP30-1~PAP80-2. The protein content was 4.92% at minimum in these polysaccharide products. In order to identify the chemical composition, the six polysaccharides (PAP30-1, PAP30-2, PAP60-1, PAP60-2, PAP80-1, and PAP80-2) were further purified by gel filtration on Sephacryl S-100-500. Finally, three water-soluble polysaccharides (PAP30-2a, PAP60-2b, and PAP80-2a) were obtained. HPLC analysis revealed that PAP30-2a, PAP60-2b, and PAP80-2a exhibited a molecular weight of 6.6 × 105 Da, 8.4 × 103 Da, and 3.5 × 103 Da, respectively. The glucose content in PAP80-2a, PAP60-2b, and PAP30-2a was 57.8%, 72.7%, and 68.9%, respectively. PAP30-2a, PAP60-2b, and PAP80-2a demonstrated significant differences in anti-tumor activity in mice. PAP80-2a is the optimal bioactive constituent with anti-tumor and T-lymphocyte proliferation stimulating effects.

Gonadotropin purification from horse serum applying magnetic beads

The glycoprotein hormone equine chorionic gonadotropin (eCG) is a commercial product used in animal breeding as well as in veterinary medicine. The current state of the art for the purification of eCG from serum is pH fractionation with metaphosphoric acid, two ethanol precipitation steps as well as dialysis followed by fixed-bed chromatography. Two simplified processes, including the use of magnetic microsorbents for the purification of eCG have been developed. The processes reduce or even omit the use of organic solvents and the required solid-liquid separation steps, thus making them potential candidates for a first commercial application of magnetic beads in bioprocessing.

Simplified purification of equine chorionic gonadotropin (eCG)––an example of the use of magnetic microsorbents for the isolation of glycoproteins from serum

Classical purification of the glycoprotein equine chorionic gonadotropin (eCG) from serum includes pH fractionation with metaphosphoric acid, two ethanol precipitation steps as well as dialysis followed by fixed-bed chromatography. A simplified process requiring only 1/3 of the solvent and improving the yield from 53 to 65% has been developed. The process comprises an ultra-/diafiltration step after the first ethanol precipitation, directly followed by an adsorption/desorption procedure based on magnetic microadsorbents with N,N-diethyl-ammonium functionalization. The process reaches an overall purification factor of eCG of more than 1800 and an average product activity of 1300 IU(ELISA)/mg. After adapting the parameters of the fractionation and the type of magnetic microadsorbents, the new concept is likely to be transferable to other serum proteins.

A two‐step electrodialysis method for DNA purification from polluted metallic environmental samples

Extracting DNA from samples of polluted environments using standard methods often results in low yields of poor-quality material unsuited to subsequent manipulation and analysis by molecular biological techniques. Here, we report a novel two-step electrodialysis-based method for the extraction of DNA from environmental samples. This technique permits the rapid and efficient isolation of high-quality DNA based on its acidic nature, and without the requirement for phenol-chloroform-isoamyl alcohol cleanup and ethanol precipitation steps. Subsequent PCR, endonuclease restriction, and cloning reactions were successfully performed utilizing DNA obtained by electrodialysis, whereas some or all of these techniques failed using DNA extracted with two alternative methods. We also show that his technique is applicable to purify DNA from a range of polluted and nonpolluted samples.

Quality of plasma and its fractionation

Human plasma (plasma for fractionation) is used as a source material for the manufacture of a large range of therapeutic products that are essential for the treatment of life‐threatening injuries as well as bleeding and immunological diseases. The industrial multistep process carried out to isolate the various therapeutic plasma proteins is known as ‘fractionation’. Typical plasma fractionation batches have a volume of 2000–4000 l obtained by pooling the individual donations from thousands of donors. The provision of safe plasma products relies upon the quality of the starting plasma and on a correct implementation of the fractionation processes, both under conditions meeting Good Manufacturing Practices (GMP) standards. The preparation of plasma for fractionation according to GMP is one key element in the quality and safety of medicinal plasma products. The quality specifications of plasma for fractionation should be precisely defined by the plasma fractionators and approved by the relevant regulatory authorities. Aspects of particular relevance for the control of infectious risks include (i) the selection criteria of blood/plasma donors, (ii) the methods used for the testing of blood/plasma donations, (iii) the epidemiological surveillance of the donor population, (iv) the adherence to GMP principles by blood establishments, and (v) the existence of a postdonation information system. Other quality aspects that may impact the range, quality, or recovery of fractionated products include the operational parameters used for plasma separation, rate of freezing and storage temperature. The industrial plasma fractionation process should be carried out under highly hygienic conditions in licenced facilities (plasma fractionation plants) operated in compliance with GMP. Manufacturing steps used to isolate the various fractions are implemented in a sequential and integrated manner. Crude fractions obtained by cryoprecipitation and cold ethanol precipitation steps are purified into individual therapeutic products most often by chromatographic methods. Validated dedicated treatments are implemented within the manufacturing process of each product to inactivate and/or remove enveloped and non‐enveloped viruses potentially present in the starting plasma pool. Recent experimental spiking studies also demonstrate that, several fractionation steps contribute to prion removal. When using current production technologies and under strict regulatory oversight, plasma products have reached a high level of quality and safety.

Prion‐removal capacity of chromatographic and ethanol precipitation steps used in the production of albumin and immunoglobulins

Although there is no epidemiological evidence to suggest that classical Creutzfeldt-Jakob disease (CJD) is transmitted through blood or blood products, the variant form (vCJD) has been implicated in transmission via packed red blood cells. The potential threat of the infectious agent contaminating plasma pools has led to manufacturing processes being examined for capacity to remove prions. The objective of these studies was to examine the prion-removal potential of the chromatographic purification and ethanol precipitation steps used to fractionate immunoglobulins and albumin from human plasma. Western blot assay was used to examine the partitioning of proteinase K-resistant scrapie prion protein (PrPsc) over DEAE Sepharose, CM Sepharose and Macro-Prep High Q chromatographic columns, utilizing microsomal scrapie 263K spiked into each scaled down feedstream and assayed after each chromatographic step. In further studies, bioassay in C57 black mice was used and spikes of 10 000 g clarified brain homogenate of scrapie ME7 were added to feedstreams before sequences of scaled down chromatographic or Cohn fractionation process steps. The microsomal spiking study with Western blot detection demonstrated substantial partitioning of PrPsc away from the target proteins in all ion exchange chromatographic steps examined. The log10 reduction factors (LRF) across DEAE Sepharose and CM Sepharose columns for albumin were > or = 4.0 and > or = 3.0 respectively. The reductions across DEAE Sepharose and Macro-Prep High Q for intravenous immunoglobulin were 3.3 and > or = 4.1 respectively. Bioassay demonstrated LRFs of >or = 5.6 across the combination of DEAE Sepharose and CM Sepharose columns in the albumin process and > or = 5.4 across the combination of DEAE Sepharose and Macro-Prep High Q columns in the intravenous immunoglobulin process. Bioassay studies also demonstrated a LRF of > or = 5.6 for immunoglobulin produced by Cohn fractionation. Using rodent-adapted scrapie as a model, the studies indicated that ion exchange chromatography, as well as Cohn immunoglobulin fractionation have the potential to effectively reduce the load of TSE agents should they be present in plasma pools.

Repair of Methylation Damage in DNA and RNA by Mammalian AlkB Homologues

Human and Escherichia coli derivatives of AlkB enzymes remove methyl groups from 1-methyladenine and 3-methylcytosine in nucleic acids via an oxidative mechanism that releases the methyl group as formaldehyde. In this report, we demonstrate that the mouse homologues of the alpha-ketoglutarate Fe(II) oxygen-dependent enzymes mAbh2 and Abh3 have activities comparable to those of their human counterparts. The mAbh2 and mAbh3 release modified bases from both DNA and RNA. Comparison of the activities of the homogenous ABH2 and ABH3 enzymes demonstrate that these activities are shared by both sets of enzymes. An assay for the detection of alpha-ketoglutarate Fe(II) dioxygenase activity using an oligodeoxyribonucleotide with a unique modification shows activity for all four enzymes studied and a loss of activity for eight mutant proteins. Steady-state kinetics for removal of methyl groups from DNA substrates indicates that the reactions of the proteins are close to the diffusion limit. Moreover, mAbh2 or mAbh3 activity increases survival in a strain defective in alkB. The mRNAs of AHB2 and ABH3 are expressed most in testis for ABH2 and ABH3, whereas expression of the homologous mouse genes is different. The mAbh3 is strongly expressed in testis, whereas highest expression of mAbh2 is in heart. Other purified human AlkB homologue proteins ABH4, ABH6, and ABH7 do not manifest activity. The demonstration of mAbh2 and mAbh3 activities and their distributions provide data on these mammalian homologues of AlkB that can be used in animal studies.

Hamster Prions Are a Suitable Model for Partitioning of Human CJD Prions during Plasma Processing Steps.

Prion removal evaluation of plasma processing procedures is one important basis to assess the margin of safety of plasma protein therapeutics. Currently, in these evaluation studies to assess the removal capacity of selected manufacturing steps for human prions mainly prions derived from scrapie-infected hamsters or mice are used in spiking studies. In order to test the validity of hamster prions instead of different human prion strains as spiking reagents, we compared the partitioning of these prion preparations at two purification steps common to the manufacturing of several human plasma-derived therapeutic proteins at ZLB Behring. The glycine precipitation (inherent in the manufacture of e.g., vWF/Factor VIII) and the 25% ethanol precipitation step (inherent in the manufacture of e.g., alpha-1-proteinase inhibitor and albumin) were down scaled to mimic the production process. A microsomal membrane preparation as well as purified full-length pathogenic prion (PrPSc; without membrane association) prepared (a) from hamster brains infected with the model scrapie strain Sc237, (b) from brains of transgenic mice infected with human sporadic CJD prions, and (c) from the brain of a patient who died of vCJD were used for spiking experiments. The different prion preparations were spiked to the starting material of the manufacturing steps studied and the manufacturing step was performed in a dedicated laboratory. The amount of PrPSc in all fractions was determined quantitatively utilizing an ELISA-formatted Conformation Dependent Immunoassay [Safar et al., Nat Med 1998; 41157–1165]. The 25% ethanol precipitation removed very effectively all prion preparations equally regardless of their origin (reduction factor ≥ 3 log10). The glycine precipitation removed the microsomal as well as the purified prion preparations from all species equally whereby prions of the purified prion preparation were removed to a considerably higher degree than the membrane preparation (reduction factor ≥ 3 log10 vs. 1.6 to 1.8 log10). In parallel, prion infectivity of each sample is currently tested in animal bioassays involving transgenic mice susceptible for the tested prion strain. It can be concluded, up to now based on immunological data, that spiked hamster prions are a reliable model to confirm the safety of human plasma-derived products also for human derived prions.

Precipitation of inulins and oligoglucoses by ethanol and other solvents

We investigated the ethanol precipitation step of the gravimetric method of dietary fiber analysis (AOAC Official Method 985.29). Four different solvents: ethanol, propanol, acetone and acetonitrile at four ratios: 1:1, 2:1, 3:1 and 4:1 (solvent : supernatant, v/v) were studied. Using inulins that contain components with a full range of degree of polymerization values (DP), we found that the percents of precipitation by these solvents were proportional to the average DP of the products. Use of ethanol and propanol produced similar results. In general, acetonitrile and acetone precipitated more of the inulins than did ethanol. Supernatant solutions were analyzed by high performance anion exchange chromatography in order to determine the size of the components that were precipitated. Our data showed that components of inulin with DP 1–10 remain in solution after the addition of ethanol at a ratio of 4:1. However, significant amounts of molecules of DP 11 and 12 and smaller amounts of molecules of DP 14–18 also remain in solution. The precipitation patterns of oligoglucoses with DP 1–DP 7 were also investigated. Our data suggest that the precipitation behavior of oligoglucoses follows a pattern similar to that of inulins.