Top PDF Oleuropein: Methods for extraction, purifying and applying

Oleuropein: Methods for extraction, purifying and applying

Oleuropein: Methods for extraction, purifying and applying

Oleuropein is one of the most abundant phenolic compounds present in olive leaves, and many studies have shown that this compound has important biological properties (anti-inflammatory, anti-atherogenic, anticancer, antimicrobial and antiviral) and that is why it has been gaining prominence in research. Oleuropein can be extracted from different sources using standard and unconventional methods, and can be recovered and purified (mainly by chromatographic techniques), for later use in several areas. The literature presents information about oleuropein alone in scientific research with different objectives, however, it was observed by the authors that studies that compile the existing information on these secoiridoides are very scarce and, therefore, this review was developed with the aim of providing current information to the scientific community, about the different techniques of extraction and purification of oleuropein, as well as the opportunities for applications and uses of this compound.
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Evaluation of methods for taxonomic relation extraction from text

Evaluation of methods for taxonomic relation extraction from text

TREC corpus. Exploiting generic patterns (ESP+), the precision decreased to 36.2% but the recall increased 8 times more when comparing with the algorithm without exploiting them. Using CHEM corpus, the algorithm without exploiting generic patterns achieved a precision of 85%. It increased the recall about 7 times but the precision decreased to 76%. As claimed by Pantel and Pennacchiotti, the addition of generic patterns substantially improves recall without much deterioration in precision. Cederberg and Widdows [16] extract hypernyms using Hearst patterns on the British National Corpus (BNC). A manual evaluation was performed using a random sample of 100 out of 513 extracted relations, from which 40% were correct relations. This precision is less than the one reported by Hearst [53]. They argue that this discrepancy could be due to the use of BNC instead of Grolier’s encyclopedia. As noted by Hearst, the encyclopedia is designed to be especially rich in conceptual relationships. In order to improve the precision LSA is applied to filter out non-related terms. It is very efficient, since LSA groups semantically related terms and let non-related terms far apart. After applying LSA, Cedeberg and Widdows evaluated another random sample containing 100 relations, achieving a precision of 58%. Recall is then improved using coordination patterns,
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Physiological quality of eggplant seeds with different extraction and drying methods

Physiological quality of eggplant seeds with different extraction and drying methods

ABSTRACT – During seed extraction in fleshy fruits, some procedures are necessary to ensure seed quality and minimize deterioration and microorganism activity; also seeds extracted under moist conditions need special care when drying. The objective of this study was to evaluate the physiological quality of eggplant seeds submitted to different extraction and drying methods. In the first study, whole eggplant fruits were mechanically crushed and then fermented for 0, 24 and 48 hours, with and without applying hydrochloric acid during seed extraction. In the second study, seeds were extracted in a pepper peeler and then immediately washed in water and submitted to the following drying methods: Sun/24 h; Sun/48 h; 32 °C/24 h; 32 °C/48 h; 38 °C/24 h; 38 °C/48 h; Sun/24 h + 32 °C/24 h; Sun/24 h + 38 °C/24 h e 32 °C/24 h + 38 °C/24 h. The treatment efficiency of both experiments was evaluated from the following tests: seed weight, germination, first count, accelerated aging and seedling emergence. The results suggest that fermentation and applying hydrochloric acid to pulp/seed reduce the physiological seed quality. All drying methods reduced the seed moisture content permitting adequate storage and maintenance of seed physiological quality.
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Applying the decision moving window to risky choice: Comparison of eye-tracking and mousetracing methods

Applying the decision moving window to risky choice: Comparison of eye-tracking and mousetracing methods

More importantly, with the complete transition ma- trix given in Table 2, one can also derive more precise, theoretically-driven metrics that are not possible with the search index. Researchers can develop exact predictions for the transition matrix based on decision making the- ories, and then compare these predictions with the em- pirical matrices (e.g., presented in Table 2). For exam- ple, many different lexicographic strategies might suggest “attribute-wise” processing and a search index value less than one—and perhaps even the same value—making them difficult to differentiate. However, these strategic variations could be captured in the transition matrix by highlighting exactly which information is predicted to re- ceive attention, and in which order. Johnson and Koop (2010) have also used this approach by training subjects to use specific, popular strategies in order to develop em- pirical estimates of their application error. Furthermore, the raw frequencies used to create Table 2 could be used for more sophisticated (e.g., Markov, sequential) analyses which are not easily obtainable with summary mouse- tracing data, such as the order of search dependencies, lag, homogeneity, or stationarity (see Gottman & Roy, 1990; Stark & Ellis, 1981).
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Retrieval of the sustainable use of traditional foods through innovative preservation and extraction methods

Retrieval of the sustainable use of traditional foods through innovative preservation and extraction methods

monovalent anion L -ascorbate (Davey et al. 2000). However, this vitamin is highly susceptible to oxidation in the presence of metal ions like Cu 2+ and Fe 3+ . Its oxidation is also influenced by light, heat, pH, oxygen and water activity (Lee et al. 2004). This vitamin has the ability to act as electron donor, being a potent in vivo antioxidant; it protects low-density lipoproteins (LDL) from the oxidation caused by different oxidative stress reactions and inhibits the LDL oxidation caused by vascular endothelial cells. The high volume of consumption of tomato all the year round makes this fruit one of the main sources for this vitamin. Different levels of have been reported in tomatoes (8-21 mg/100 g of fresh weight) (Abushita et al. 2000, Frusciante et al. 2007, Pinela et al. 2012), since it is affected by different factors. In turn, vitamin E includes eight chemically distinct molecules (Figure 9), four tocopherol isoforms (α-, β-, γ- and δ-tocopherol) and four tocotrienol isoforms (α-, β-, δ- and γ-tocotrienol) (Carocho and Ferreira 2013). Tocopherols differ from the corresponding tocotrienols in the aliphatic tail; tocopherols have a phytyl side chain attached to the chromanol head, whereas the tail of tocotrienols contains three trans double bonds at the 3', 7' and 11' positions and forms an isoprenoid chain. These unsaturations in the tail of tocotrienols give only a single stereoisomeric carbon, whereas tocopherols have eight possible stereoisomers per structural formula. The various isoforms differ in the methyl substituents on the chromanol head; the α- forms contain three methyl groups, the β- and γ- have two and the δ-forms have only one methyl group. Together, tocopherols and tocotrienols are called tocochromanols. All these compounds feature a chromanol ring with a hydroxyl group capable of donating a hydrogen atom, and a lipophilic side chain that allows for penetration into cell membranes (Baiano and Del Nobile 2015). The donation of hydrogen atoms to the peroxyl radicals forms unreactive tocopheroxyl radicals (TO • ) unable to continue the oxidative chain reaction (Burton and Traber 1990). The human body absorbs all forms of vitamin E, but maintains only the α- tocopherol (Packer et al. 2001). The amounts of tocopherols also vary in tomatoes, having been reported values from 0.17 to 1.44 mg/100 g of fresh weight (Frusciante et al. 2007, Pinela et al. 2012). Nevertheless, neither vitamin C nor vitamin E can be synthesized by humans, so their intake must be guarantee through the diet (Giovannoni 2007, Baiano and Del Nobile 2015).
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COMPARISON OF RNA EXTRACTION METHODS FOR Passiflora edulis SIMS LEAVES

COMPARISON OF RNA EXTRACTION METHODS FOR Passiflora edulis SIMS LEAVES

was added to 100 mg of P. edulis SIMS leaf tissue in a microcentrifuge tube, ground using liquid nitrogen and homogenised using a vortex. After 5 min incubation at room temperature, 0.2 mL of chloroform was added, and the mixture was agitated for 15 s. After 3 min, the sample was centrifuged at 12000 g for 15 min at 4°C. The aqueous phase was transferred to a new microcentrifuge tube, and 0.5 ml of isopropanol was added. then, the sample was incubated at room temperature for 10 min and subsequently centrifuged at 12000 g for 10 min at 4°C. The supernatant was removed from the tube, and the RNA pellet was washed with 1 mL of 75% ethanol, vortexed and centrifuged at 7500 g for 5 min at 4°C. The wash was discarded. After the microcentrifuge tube was dried, the RnA pellet was resuspended in 20 µl of ultrapure Rnase-free water.
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Topic Modeling for Keyword Extraction: using Natural Language Processing methods for keyword extraction in Portal Min@s

Topic Modeling for Keyword Extraction: using Natural Language Processing methods for keyword extraction in Portal Min@s

during the colonization and exploration of continents such as Africa by some of the empires in the 18 th and 19 th centuries. It also presents words like cabeça (head) and olhos (eyes) that indicate a fragmented representation of the native population found in the description of the narrator (MAGALHÃES; ASSIS, 2009). However, this framework does not provide list words such as parecia (seemed / singular), pareciam (seemed / plural), escuridão (darkness), among others, indicators of key topics in the texts, such as uncertainty (STUBBS, 2005) and difficulty to understand what you see in a very different violent clash of cultures with a very distinct power position. The experiment of human analysis of word lists generated by the LDA method allowed the clustering of these words into very general topics, such as physical and human nature. It also pointed to the fact that the words found in lists in which the physical nature topic predominates would most likely be keyword candidates. On the one hand, the two general topics, physical nature and human nature, permeate the work, which can be interpreted as a representation of the Western man’s confrontation with the devastation of human and physical natures in a context of colonization. For example, some words from these lists coincide with some of those presented in Table 4, such as Kurtz, pilgrims, earth and ivory. On the other hand, these general topics leave out words generated by the LDA lists (qualquer [any], nenhuma [none], parecia [seemed], etc.), also constituents of other more specific topics, but fundamental in the novel, such as the uncertainty and difficulty of understanding the landscape in the novel. Other words such as escuridão (dark), trevas (darkness), sombra (shadow) are key indicators of the specific topics are not necessarily inferred from general topics either. ics.
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Extraction of Indigo from Some Isatis species and Dyeing Standardization Using Low-technology Methods

Extraction of Indigo from Some Isatis species and Dyeing Standardization Using Low-technology Methods

Various shades of blue color were obtained in all the tested Isatis species, except I. buschiana. The shades of light blue were much more than yellow- greenish and were obtained in I. tinctoria subsp. corymbosa while the most desired blue colors were obtained from I. tinctoria and I. candolleana. In caustic-hydrosulphite method, which is widely used to reduce indigo, dyeing vat is generally prepared in 80 g l -1 concentration. An excess of reducing agent results in irregular dyeing and increase of ecological damage (Kumbasar et al. 2006). For this reason, the control of pH and reducing agent concentrations are very important and this study represents an environmental friendly process with a small amount of hydrosulphite resulting succesfull dyeings. Hot water extraction method was reported as the most suitable choice to fulfill the extraction immediately after the harvest (Bechtold et al. 2002). It was simple and the yield could be obtained in the same day; however, this method required higher energy consumption. Energy consumption is not necessary for extraction with fermentation, but bad odor and overflows are the main problems and extra time is required for better results. However, simple and rapid dyeing process, no intermediate drying steps and one bath dying are the requirements of a technical dyehouse
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Evaluation of methods for the extraction and purification of DNA from the human microbiome.

Evaluation of methods for the extraction and purification of DNA from the human microbiome.

Here we sought to compare the ability of six DNA extraction methods previously used in studies of the human microbiome and environmental samples to recover DNA from known organisms and yield genomic DNA representative of mock community. We found that observed species abundances from all six DNA extraction methods did not match the expected species abun- dances, and the differences between them were significant. This bias could be ascribed to many factors in addition to DNA extraction efficiency. For example, the copy number of the chromosome can vary depending on growth phase [39,40], and bias can occur during PCR amplification since the ‘‘universal’’ primers used are not really universal [28]. In addition, genome size and rrn gene copy number also have an effect on PCR [41]. Because this study was not designed to evaluate the effect of those factors mentioned above on observed relative abundance, we tried to minimize biases introduced by those factors. First, the cells used were harvested in post-exponential phase of growth to reduce the variation of chromosome copy number. Second, a mixture of forward primers (27F) were used to minimize the PCR amplification bias [42]. Third, information on the rrn gene copy number of each strain was taken into account to calculate the expected relative abundances. Therefore, in this case, DNA extraction efficiency was likely to be the main factor that introduced bias between observed and expected relative abun- dance.
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Extraction methods and availability of phosphorus for soybean in soils from Parana State, Brazil

Extraction methods and availability of phosphorus for soybean in soils from Parana State, Brazil

In studies on the evaluation of methodologies for the analysis of soil, phosphorus (P) has been the single most studied aspect, due to the complexity of this dynamic element in soil. However, these studies have been limited regarding soil conditions in Paraná. The present study aimed to evaluate the eficiency of the Mehlich-1, Mehlich-3 and ion exchange resin methods in the evaluation of available P for soybean (Glycine max) in the soils of Paraná State. Twelve soil samples collected from the upper 0-20 cm were planted with soybean for a period of 42 days in the greenhouse. The ability to extract soil P followed the order of decreasing average amount of extracted P: Mehlich-3 > resin > Mehlich-1. The correlation coeficients between the content of P extracted by Mehlich-1, Mehlich-3 and resin and the amount of P accumulated in the plants were 0.86, 0.90 and 0.93, respectively. Mehlich-1, Mehlich-3 and resin showed similar eficiency in the evaluation of P availability to plants and, under conditions of natural fertility and in soils that had received no application of poorly natural reactive phosphates, can be used to quantify the concentrations of P in the soils of Paraná State.
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Evaluation of protein extraction methods for enhanced proteomic analysis of tomato leaves and roots

Evaluation of protein extraction methods for enhanced proteomic analysis of tomato leaves and roots

Proteomics is an outstanding area in science whose increasing application has advanced to distinct purposes. A crucial aspect to achieve a good proteome resolution is the establishment of a methodology that results in the best quality and wide range representation of total proteins. Another important aspect is that in many studies, limited amounts of tissue and total protein in the tissue to be studied are found, making difficult the analysis. In order to test different parameters, combinations using minimum amount of tissue with 4 protocols for protein extraction from tomato (Solanum lycopersicum L.) leaves and roots were evaluated with special attention to their capacity for removing interferents and achieving suitable resolution in bidimensional gel electrophoresis, as well as satisfactory protein yield. Evaluation of the extraction protocols revealed large protein yield differences obtained for each one. TCA/acetone was shown to be the most efficient protocol, which allowed detection of 211 spots for leaves and 336 for roots using 500 µg of leaf protein and 800 µg of root protein per gel.
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Applying Mathematical Optimization Methods to an ACT-R Instance-Based Learning Model.

Applying Mathematical Optimization Methods to an ACT-R Instance-Based Learning Model.

Computational models of cognition provide an interface to connect advanced mathematical tools and methods to empirically supported theories of behavior in psychology, cognitive science, and neuroscience. In this article, we consider a computational model of instance- based learning, implemented in the ACT-R cognitive architecture. We propose an approach for obtaining mathematical reformulations of such cognitive models that improve their computational tractability. For the well-established Sugar Factory dynamic decision making task, we conduct a simulation study to analyze central model parameters. We show how mathematical optimization techniques can be applied to efficiently identify optimal parame- ter values with respect to different optimization goals. Beyond these methodological contri- butions, our analysis reveals the sensitivity of this particular task with respect to initial settings and yields new insights into how average human performance deviates from poten- tial optimal performance. We conclude by discussing possible extensions of our approach as well as future steps towards applying more powerful derivative-based optimization methods.
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Comparison of Four Extraction Methods to Detect Hepatitis A Virus RNA in Serum and Stool Samples

Comparison of Four Extraction Methods to Detect Hepatitis A Virus RNA in Serum and Stool Samples

Compared to blood or other clinical samples, the complex microbial flora, variable consistency and variable endogenous and dietary components of feces make RNA extraction particularly difficult. The purity of RNA extracted from this heterogeneous material is critical for the sensitivity and usefulness of further analyses, such as PCR analysis for infectious pathogens. When we evaluated the four extraction methods, the proteinase K method detected HAV RNA in 11 of 12 serum samples. Probably this technique was the most efficient, because the use of the proteinase K solution followed by phenol-chloroform extraction reduces the concentration of residual protein and membrane components that could inhibit Taq polymerase activity. RNA extraction with phenol- chloroform is the most labor-intensive method and it requires additional safety measures for the handling and disposing of phenol. In other studies phenol-chloroform method was reported to be more effective in extracting viral RNA from serum than other techniques [25-26]. The results obtained with TRIzol confirmed that this technique can be used with serum samples, as previously demonstrated by other researchers [27]. This technique is one of the most suitable for routine diagnosis, in view of its rapidity. However, the presence of lipids in serum samples can interfere in extraction and also in amplification, leading to false negative results. The silica RNA extraction method was the least efficient for the extraction of hepatitis A virus. This method is frequently used for the virological testing of serum and stool specimens [28-29]. However, it requires complicated buffers, various ultracentrifugations and careful pipetting to remove the RNA solution from the silica beads. The additional pipetting or handling required can increase the risk of losing the RNA. Only 50% of the specimens were positive with this method.
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Comparative study of two extraction methods for enteric virus recovery from sewage sludge by molecular methods

Comparative study of two extraction methods for enteric virus recovery from sewage sludge by molecular methods

As shown in Figs 2 and 3, the detection limits for the viruses seeded before and after the elution step using the organic-based method were, respectively: 0.63 PFU and 0.126 PFU (AdV5), 24 FFU and 21.6 FFU (RV), 0.0072 FFU (HAV) and 18.8 PFU (PV) (the last 2 viruses gave the same results both before and after elution). The de- tection limits of the silica method were: 560 PFU and 10.08 PFU (AdV5), 192 FFU and 172.8 FFU (RV) (Fig. 2). The results from the tests of the different viral extrac- tion methods using sewage sludge samples artificially contaminated with AdV5, RV, PV or HAV are shown in Table. When the detection limits were compared with the positive controls (100% recovery), the organic-based method detected 20% of the AdV5, 90% of the RV and 100% of both the HAV and the PV2. The silica method detected 1.8% of the AdV5 and 90% of the RV. Our re- sults showed that the sensitivity of the RT-nested-PCR
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Utilizing field collected insects for next generation sequencing: effects of sampling, storage and DNA extraction methods

Utilizing field collected insects for next generation sequencing: effects of sampling, storage and DNA extraction methods

Specifically, molecular studies of insects can be challenging because many of the standard field sampling and lab preservation methods that are traditionally used in entomology collections are especially prone to DNA degradation problems. The most common ways of collecting insects often involve capturing insects in traps without preservative, or in soapy water, where they can remain for several days (e.g. pan, pitfall, and blue vane traps; LeBuhn, Griswold, Minckley, & Droege, 2003; Potts et al., 2005; Rubink, Murray, & Baum, 2003), likely leading to DNA degradation. Hand netting into a kill jar may expose specimens to chemicals that could also degrade DNA (e.g. ethyl acetate, Dillon, Austin, & Bartowsky, 1996). Trapping using a preservative such as propylene glycol has been shown to be an effective method for DNA preservation of several invertebrate species (Dillon et al., 1996; Ferro & Park, 2013), but the effects of propylene glycol on NGS results are not known. Although trapping into an EtOH preservative could potentially be done, EtOH evapo‐ rates rapidly and so it must be refilled, which can be a hinderance to sampling in high temperatures, over large geographic scales, or longer time periods; in contrast, trapping without preservative in the trap or with propylene glycol is common in low resource areas (e.g., desert and dry grasslands) as these traps may be set for several days or even months at a time (Rubink et al., 2003; Stephen & Rao, 2005; Sudan, 2016). While some studies suggest netting samples directly into EtOH for NGS (e.g. Moreau, Wray, Czekanski‐Moir, & Rubin, 2013), this technique also presents major challenges as it is time‐ consuming, with a capture rate that can be 3‐17x lower than trapping (Figure 1; Roulston, Smith, & Brewster, 2007; Stephen & Rao, 2007), and can only be used on field‐identifiable species. In practice, spe‐ cies identification of many insect groups requires morphological trait assessment that can only be determined under magnification and after pinning and drying in order to visualize minute morphological features (Huber, 1998), some of which are compromised after long‐ term storage in EtOH (e.g. hair color and growth patterns; J. Neff, pers. comm.). However, specimen curation that forgoes EtOH stor‐ age and instead optimizes morphological identification and speci‐ men cataloguing may lead to additional DNA degradation (Andersen & Mills, 2012; Gilbert, Moore, Melchior, & Worobey, 2007; Strange, Knoblett, & Griswold, 2009), that may compromise use in genetic or genomic studies.
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Extraction methods and availability of micronutrients for wheat under a no-till system with a surface application of lime

Extraction methods and availability of micronutrients for wheat under a no-till system with a surface application of lime

rate increased linearly Zn concentrations extracted by DTPA-TEA solution (5:1) at 5-10 cm layer. This can be interpreted as a direct effect of the high chelation capac- ity as proportioned by 5:1 solution/soil ratio used in Method-2. Norvell (1984) proposed to use a greater solu- tion/soil ratio to compensate the limitations of extractants, mainly of their chelation capacity in soil at low pH. For the other depths and procedures, changes on extractable Zn concentrations after liming treatments were not ob- served. Acid extractants have normally not been efficient to detect slight changes in extractable Zn as a consequence of liming, becoming a hard task to select an adequate ex- tractant for this micronutrient (Abreu et al., 2007). Figure 1 - Soil copper (Cu) concentrations extracted by different procedures as affected by surface-applied lime rates, without (z) and
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Dissecting Fact-Checking Systems: The Impact of Evidence Extraction Methods

Dissecting Fact-Checking Systems: The Impact of Evidence Extraction Methods

Fact-checking in natural language became more visible through the creation of challenges such as the FEVER challenge [ 111 ]. This challenge tries to bring together the best of different research topics in Natural Language Processing such as Question Answering, Information Retrieval and Natural Language Inference in order to create an end-to-end system capable of finding at least one evidence that can be used to prove a given claim. Locating documents is the first step in the search for evidence, as it is where the text passages with relevant information should be presented. The detection of sentences and, above all, checking their stance, enable the preponderance to check all sides of a given statement being one of the first steps of real-life fact-checkers. Any automatic system will not always be correct, so it is essential to complement it with a human check. Hence, the need arises for all stages of a fact-checking system to be available and easily understood by the people who can work with it. Thus, automated fact-checking frameworks are valuable assets for modern society, but the development of such technology is still in the early stages. A critical step to the performance of such frameworks is Evidence Extraction, which comprehends the Document Retrieval and Evidence retrieval sub-tasks. The performance of each step was investigated in the DeFactoNLP system, a framework which participated in the FEVER 1.0 challenge. We investigated and further demonstrated the impact that these early stages have on the overall performance.
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Extraction of β-glucan from Saccharomyces cerevisiae: Comparison of different extraction methods and in vivo assessment of immunomodulatory effect in mice

Extraction of β-glucan from Saccharomyces cerevisiae: Comparison of different extraction methods and in vivo assessment of immunomodulatory effect in mice

Beta-glucan (BG) is a conserved cell wall components of bacteria, fungi, and yeast. BG is an immunomodulator and stimulates the host immune system. This study was performed to screen Saccharomyces cerevisiae strain with high BG, extraction of BG using different chemical extraction methods, composition analysis of BG, and evaluation of the immunomodulatory effect of high-quality BG using mice model. Ten yeast strains were screened for high BG content using total glucan extraction kit and were subjected to FT-IR analysis. The kit based extraction revealed that HII31 showed a high content of total glucan and BG. HII31 cells were subjected to four different acid/base extractions, which indicated that combination of a strong base (NaDH) and weak acid (CH 3 CDDH) extraction recovered high BG and a high ratio of polysaccharide, protein, and lipid. Further, the immunomodulatory effect of the selected BG was evaluated using mice, which suggested that low dose of HII31-BG induces the expression of selected pro-inflammatory (IL-17, IFN-γ) and anti-inflammatory cytokine (IL-10) significantly, whereas relatively high dose was required to alter the IL-6 and TGF-β expression. Dverall, the present study revealed that BG extracted from HII31 cells alters the expression of studied cytokines, which can be used as a potent immunomodulator in pharmaceutical products. Keywords: beta-glucan; Saccharomyces cerevisiae; immunomodulation; FTIR; cytokines.
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Extracting natural dyes from wool—an evaluation of extraction methods

Extracting natural dyes from wool—an evaluation of extraction methods

Spain); sodium hydroxide (NaOH) from Akzo Nobel (Amsterdam, The Netherlands); EDTA disodium salt from Sigma-Aldrich (Milwaukee, WI, USA); pyridine from Fluka (Buchs, Switzerland); oxalic acid from Riedel-de- Haën (Seelze, Germany) and acetone from Vaz Pereira (Lisbon, Portugal). Methanol, acetonitrile and formic acid (HPLC grade) were purchased from Merck (Darmstadt, Germany). Water purified by a Millipore Simplicity UV system (Billerica, MA, USA) was used for sample preparation and all the analyses. Alum, weld (R. luteola L.), cochineal (Dactylopius coccus Costa), woad (I. tinctoria L.), brazilwood (Caesalpinia spp.), madder (R. tinctorum L.) and logwood (H. campechianum L.) were purchased from Kremer Pigmente GmbH & Co. KG (Aichstetten, Germany). Standards of haematein, alizarin, carminic acid, brazilin, apigenin and indigotin were obtained from Fluka (Buchs, Switzerland); luteolin and haematoxylin were purchased from Sigma (St. Louis, MO, USA) and purpurin was acquired from Eastman Organic Chemicals (Rochester, NY, USA); luteolin 7-O-glucoside was obtained from Extrasynthèse (Genay, France). Undyed industrial Arraiolos sheep wool was acquired from Rosarios4 (Mira de Aire, Portugal).
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