Alkali Extraction Method Research Articles

A comparative study of analytical methods for alkali-soluble β-glucan in medicinal mushroom, Chaga ( Inonotus obliquus)

Crude β-glucan content in the medicinal mushroom Chaga ( Inonotus obliquus) was measured by different extraction and analytical methods, and the results were compared. The alkali extraction (AE) method or enzymatic digestion (ED) method followed by a gravimetric analysis was employed to determine the crude β-glucan content. The amount of crude β-glucan in Chaga obtained by either AE or ED was 13.7 g/100 g or 15.3 g/100 g of the sample, respectively. Crude β-glucan content of Chaga obtained by the above preparation methods were corrected by chemical composition analysis and HPLC analysis. After composition analysis, the amounts of β-glucan measured in the 100 g Chaga samples were corrected to 10.1 g for ED and 10.7 g for AE method. β-glucan contents calculated by the amount of glucose in the HPLC analysis were 8.3 g/100 g and 8.1 g/100 g for ED and AE preparation methods, respectively. Although extraction method did not affect β-glucan content in Chaga as indicated by no significant difference ( P>0.05) between extraction method, significant differences ( P<0.05) were noted between the correction methods. The discrepancies of the result indicate a need for standardization of analytical method for β-glucan measurement in Chaga

Enzymatic polymerization on the surface of functionalized cellulose fibers

Enzymatic coating of functionalized cellulose fibers with catechol was performed in the presence of Trametes hirsuta laccase. Cellulose functionalization was done by covalent fixation of aromatic amines onto the cellulose surface using a dyeing procedure with C.I. Reactive Black 5 (RB5) followed by reduction with sodium hydrosulfite. Cellulase enzymes were used on coated and control samples to obtain the analytes linked with the soluble sugars in solution, to prove the reaction concepts described in this paper. Hydrolyzed coated-cellulose showed lower concentration of reducing sugars (1188 mg/L) than control samples (2011 mg/L). The structures of these compounds were checked by LC/MS analysis confirming the presence of functionalized glucose and cellobiose units coupled to poly(catechol) molecules ( m/ z 580 and m/ z 633). Alkali extraction method showed to be very promising to coat cellulose fibers with phenols in the presence of enzymes, at mild conditions of temperature and pH.

Pulsed electric field extraction of polysaccharide from Rana temporaria chensinensis David

In order to develop and optimize a pulsed electric field (PEF) extraction method and evaluate it against conventional extraction methods for the extraction of polysaccharide from Rana temporaria chensinensis David, we have investigated various experimental conditions, respectively, such as electric field intensity (10–30 kV/cm), pulse duration (2–6 μs) and concentration of distilling solvent (0–1% KOH, v/v), and then optimized them by an orthogonal experiment. The result showed that the largest extraction ratio is 55.59% by PEF on the conditions of 0.5% KOH, 20 kV/cm electric field intensity and 6 μs pulse duration. Comparing it with the conventional extraction methods, such as alkali extraction method, enzyme extraction method and compound extraction method, the extraction ratio and polysaccharide content of PEF method are higher than the other three methods. The PEF extraction ratio for 6 μs is 1.77 times the compound extraction method for 6 h, the total sugar contents are more than 26.34% of that for the compound extraction method and the impurity of extraction material is less. So the PEF method is a novel and promising method to extract polysaccharide of R. temporaria chensinensis David.

미생물을 이용한 미역줄기에서 알긴산염 추출 및 저분자화

We studied a extraction and degradation of alginate from seaweed-stems using microorganism DS-02. DS-02 has a maximum growth rate at <TEX>$30^{\circ}C$</TEX> and the enzyme has a maximum activity of alginate extraction at <TEX>$35^{\circ}C.$</TEX> The yield of alginate extraction using DS-02 is about <TEX>$16.0{\%}$</TEX> for 3.0 hour and molecular weight of the alginate decreased to about 1/8 of initial value after 24 hour extraction. Alginate extraction method by DS-02, compared with general alkali-extraction method, has an advantage of decreasing the molecular weight of alginate during extraction.

Separation, characterization and hydrogel-formation of hemicellulose from aspen wood

Hemicellulose from aspen ( Populus tremula) was isolated by an alkali extraction method, which was followed by hydrogen peroxide treatment, ultrafiltration and recovery by spray drying. The sugar composition and lignin content were monitored with HPLC at each step of the separation procedure. Size-exclusion chromatography showed a polymeric hemicellulose of relatively high molar mass. The product was characterized by 1H and 13C NMR spectroscopy and was found to be composed of a linear (1→4)-β-linked d-xylose main chain with a 4- O-methyl-α- d-glucuronic acid substituting the 2-position of approximately every eighth xylose unit. Lignin and O-acetyl groups had largely been removed in the separation process. The xylan was soluble in hot water, and the film forming properties were examined at various mixtures of the hemicellulose and chitosan. These films formed hydrogels with a high swelling capacity at certain compositions. The morphologies of the films were examined with wide angle X-ray spectroscopy, and a pure xylan film was found to be crystalline, which was suggested to be a consequence of the lack of O-acetyl groups. The crystallinity of the films was found to decrease with an increasing amount of chitosan, and the film of chitosan alone showed no crystallinity. The cohesive forces of the hydrogels are suggested to be the result of the crystalline arrangement of the polymers and of electrostatic interactions between acidic groups in the hemicellulose and amine groups in the chitosan.

Rapid and Sensitive Detection of Xanthomonas fragariae by Simple Alkaline DNA Extraction and the Polymerase Chain Reaction

AbstractMethods for DNA preparation from Xanthomonas fragariae in infected or artificially contaminated strawberry plants were compared in diagnostic assays using the polymerase chain reaction (PCR). The bacterium was detected using PCR with primers specific to a region of its hrp gene. Sensitivity of detection was 1.25 ×l 103 CFU ml‐1 using DNA from bacterial suspensions prepared by an alkali extraction method. This was 10‐fold more sensitive than DNA extraction by boiling, and was equal to that in which DNA was prepared by a more involved cetyltrimethylammonium bromide (CTAB) procedure. Sensitivity of detection from artificially contaminated strawberry tissues was 10‐fold less than that from cell suspensions. The results indicated that a rapid and simple method of alkali DNA sample preparation is applicable for the sensitive and reliable detection of X. fragariae and possibly other plant pathogenic bacteria.

Isolation and partial characterization of cellulose produced by Acetobacter xylinum

A mechanical separation method and an alkali treatment for the isolation of bacterial cellulose were developed. Response surface methodology was employed to determine the optimum conditions for the isolation of bacterial cellulose. A homogenizing mill was used to shear and separate the cellulose fiber from the bacterial cells. Cells were then removed by centrifugation and washing with distilled water. The optimum conditions obtained for the mechanical separation method were 1:1.9 gel to water ratio, 15 min of homogenization and 5 centrifugation-washing cycles. The isolated cellulose had 0.46% nitrogen and 1.46% ash (dry weight basis). The whiteness index (WI) of the product was 30.3 as measured by a Hunterlab colorimeter. For the alkali extraction method, the optimum conditions for the isolation of bacterial cellulose were 0.30 mol/dm 3 NaOH (~1.2%) at 90°C for 25 min. The product had 0.08% nitrogen, 0.66% ash and a WI of 44.2. The isolated bacterial cellulose had 3–5 times higher water holding capacity than commercial cellulose powders as determined by the centrifugation method. Any form of drying reduced its water holding capacity, but it was higher than that of commercial celluloses.

SENSITIVITY ANALYSIS FOR TRONA SOLUTION MINING

Mineral Resources EngineeringVol. 04, No. 02, pp. 201-213 (1995) No AccessSENSITIVITY ANALYSIS FOR TRONA SOLUTION MININGG. NASÜN-SAYGILI and H. OKUTANG. NASÜN-SAYGILIIstanbul Technical University, Chemical and Metallurgical Faculty, Chemical Engineering Department, 80626 Maslak-Istanbul, Turkey Search for more papers by this author and H. OKUTANIstanbul Technical University, Chemical and Metallurgical Faculty, Chemical Engineering Department, 80626 Maslak-Istanbul, Turkey Search for more papers by this author https://doi.org/10.1142/S0950609895000199Cited by:0 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail AbstractDuring the past decade, solution mining of trona has emerged as a viable alternative to conventional mining technology applications. The significance of this production level becomes quite apparent for soda ash production after 1980’s. Areas of investigation of Turkish trona mineral have generally focused on leaching chemistry, solution flow characteristics and surface plant parameters. Economics of trona solution mining was investigated for Turkish trona deposit to offer comparative estimates of this method and conventional mining techniques. This study presents the results of an in-depth analysis of in situ trona production costs by employing a process engineering approach. This approach disaggregates the solution mining process and analyzes each component in terms of its requirements and associated costs. The cost model developed under this effort has been applied to typical solution mining situation encountered in Beypazari. Sensitivity tests were also conducted to identify the degree of cost influence exerted by incremental changes in key project parameters. The method considered here is alkali extraction method. FiguresReferencesRelatedDetails Recommended Vol. 04, No. 02 Metrics History PDF download

Isolation of humin by liquid-liquid partitioning

A method is described for isolating humin from diverse samples by partitioning the organic components between methyl isobutyl ketone (MIBK) and an aqueous phase as a function of pH. The humin isolated by the MIBK method is similar to humin isolated from the same sample by more traditional alkali-extraction methods. The MIBK method may be extended to separate the organic components of humin from its inorganic or non-humic organic constituents. It is shown that the organic components of humin consist of lipids and a humic acid-like material. In this study the MIBK method was applied to a soil, a peat and a stream sediment sample.

Acid pyrophosphate extraction of soil fulvic acids

SUMMARYA simple three step method is described for isolation of soil fulvic acids in high yield. The complexing agent H2P2O72− (at pH 2) is used to release soil‐bound fulvic acids. Extraction of humic acids is minimal. Selective separation of the protonated fulvic acids from the ionic extractant is achieved on a non‐ionic polyacrylate resin (Amberlite XAD‐7); after washing the resin, fulvic acids were retrieved in &gt;98% yield by adjusting the pH to 6.5. Two problems associated with the classical alkali extraction method are avoided: possible alkaline oxidation of phenolic components, and their oxidation by Fe3+ under the acidic conditions employed to precipitate humic acids. The product typically has an ash weight of &lt;0.6% after one XAD treatment. The method has been applied to three soils and one IHSS peat sample.

Simplified Determination of Soil Humus by Alkali Extraction Method

Simplified Determination of Soil Humus by Alkali Extraction Method

Comparative potency of growth hormone preparations in alkali or acid.

Growth hormone preparations obtained from beef pituitary through alkali extraction (methods of Li and Wilhelmi) were compared for growth activity in hypophysectomized rats with acid extracted porcine growth hormone (method of Raben). The alkali extracted preparations showed reduced activity when assayed in acid media. The reduced potency was shown to result from storage at the acid pH, rather than from inactivity at the time of injection. Hydrochloric acid was shown to be more damaging than acetic acid of comparable pH. Somatotropic preparations obtained from beef or pork pituitary through acid extraction showed no difference when assayed in basic or acidic media. It was concluded that the differential effect of pH on Li or Wilhelmi growth hormone as compared to Raben type preparations is not due to the gland source, but rather to the method of preparation.