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ACEMANNAN: Kumpulan informasi

Extraction of acetylized mannan from aloe juice

Inventor: DONG YINMAO (CN); ZHAO HUA (CN); (+1)

EC: IPC: C08B37/02; C08B37/00; (IPC1-7): C08B37/02
Publication info: CN1424331 - 2003-06-18

Abstract :
A process for extracting acetylated mannosan from raw aloe juice includes such steps as mixing, microwave treating, centrifugal separating, and freeze drying. Its advantages are high output rate (0.2%), high speed, less consumption of energy and solvent and low pollution.

Chemical characterization of the immunomoduling polysaccharide of aloe vera L.

Jimmy Tai-Nin Chow; David A. Williamson; Kenneth M. Yates; Warren J. Goux Carbohydrate Research ,340(6):1131-1142

Data provide direct evidence of a previously proposed glucomannan backbone, but draw into question previously proposed side-chain structures for the polysaccharide from the mucilaginous gel of Aloe vera.The polysaccharide isolated by alcohol precipitation of Aloe vera mucilaginous gel was found to have a Man:Glc:Gal:GalA:Fuc:Ara:Xyl ratio of 120:9:6:3:2:2:1 with traces of Rha and GlcA. Linkage analysis of the endo-(1→4)-β-d-mannanase-treated sample yielded Man p-(1→ (∼26%), 4-Man p (∼53%), 2,4-Man p (∼3%), 3,4-Man p (∼1%), 4,6-Man p (∼1%), 4-Glc p (∼5%), 4-Xyl p (∼1%), Xyl p-(1→ (∼2%), Gal p-(1→ (∼5%), and traces of 4,6-Gal p and 3,6-Gal p. Hydrolysis with strong acids produced a mixture of short oligosaccharides and an acid-resistant fraction containing greater relative fractions of Man p-(1→, Ara f-(1→, Xyl p-(1→, and 4-Xyl p than the bulk polysaccharide. NMR analysis of oligosaccharides generated by endo-(1→4)-β-d-mannanase and acid hydrolysis showed the presence of di-, tri-, and tetrasaccharides of 4-β-Man p, β-Glc p-(1→4)-Man, β-Glc p-(1→4)-β-Man p-(1→4)-Man, and β-Man p-(1→4)-[α-Gal p-(1→6)]-Man, consistent with a backbone containing alternating →4)-β-Man p-(1→ and →4)-β-Glc p-(1→ residues in a ∼15:1 ratio. Analysis of the sample treated sequentially with endo-(1→4)-β-d-mannanase and α-d-galactosidase showed that the majority of α-Gal p-(1→ residues were linked to O-2, O-3, or O-6 of →4)-β-Man p-(1→ residues, with ∼16 →4)-β-Man p-(1→ residues between side chains. Our data provide direct evidence of a previously proposed glucomannan backbone, but draw into question previously proposed side-chain structures.
Keywords:13; C NMR; 1; H NMR; Acemannan; Aloe vera; Polysaccharide; Immunostimulant; Immunomodulator

Extraction process of acetylated aloe glucomannan


EC: IPC: A61K31/715; C08B37/00; A61K31/715 (+2)
Publication info: CN1432581 - 2003-07-30

Abstract :
A separation and purification process of acetylated aloe glucomannan from aloe juice includes adding special biochemical enzyme to aloe juice straining and ultrafiltering to obtain concentrated aloe juice; adding organic solution to concentrated aloe juice to extract coarse aloe polysaccharide, water washing and filtering; ultrafiltering and concentration to obtain water solution o purified acetylated aloe glucomannan; and freeze drying to obtain powder. The said process combines separation and concentration, maintains the activity of acetylated aloe glucomannan, and can be used in industrialproduction.

Extraction refining method for aloe-polysaccaride

Inventor: TAN RENXIANG (CN); XU CHEN (CN); (+1)

Applicant: UNIV NANJING (CN)
Publication info: CN1418892 - 2003-05-21

The method for extracting and refining aloe polysaccharide includes the following steps: uctting fresh leaf of aloe into small block, extracting with water at 40-80 deg.C, filtering extract, centrifugation and taking out supernatant fluid, adding 95% ethyl alcohol in the supernatant fluid, making the ethyl alcohol content be up to 50-80%, precipitating crude aloe polysaccharide, dissolving said crude aloe polysaccharide in water, adding 20-50% trichloroacetic acid or trifluoroacetic acid to make end concentration of trichloroacetic acid or trifluoroacetic acid be up to 2-6%, standing still, then centrifugation to remove precipitate to obtain secondary supernatant fluid, feeding it into macroporous resin column bed and using water to make elution, concentrating and adding 95% ethyl alcohol, precipitating polysaccharide, freeze-drying so as to obtain refined aloe polysaccharide.

Extraction of aloe extract


EC: IPC: A23L2/38; A23L2/385; A23L2/44 (+8)
Publication info: CN1216232 - 1999-05-12


After fresh aloe leaf is cleaned, soaked in disinfection solution for 10-20 min, washed and drip-dried, the rind and gel are separated in special aloe peeler, treated separately and mixed to produce aloe juice, concentrated aloe juice, aloe powder and other product, which may be mixed with some additive in certain amount to produce various final products. The present invention can retain the effective components in aloe fully and control the content of anthraquinone and glycosides. Using instantaneous high-temperature degradation process to replace chemical process in treating aloe juice can reduce production cost greatly.

Acemannan purified from Aloe vera induces phenotypic and functional maturation of immature dendritic cells.

Lee JK, Lee MK, Yun YP.
Int Immunopharmacol. 2001 Jul;1(7):1275-84.
College of Pharmacy, Chungbuk National University, Cheongju 361-763, South Korea.

Acemannan, a major carbohydrate fraction of Aloe vera gel, has been known to have antiviral and antitumoral activities in vivo through activation of immune responses. The present study was set out to define the immunomodulatory activity of acemannan on dendritic cells (DCs), which are the most important accessory cells for the initiation of primary immune responses. Immature DCs were generated from mouse bone marrow (BM) cells by culturing in a medium supplemented with GM-CSF and IL-4, and then stimulated with acemannan, sulfated acemannan, and LPS, respectively. The resultant DCs were examined for phenotypic and functional properties. Phenotypic analysis for the expression of class II MHC molecules and major co-stimulatory molecules such as B7-1, B7-2, CD40 and CD54 confirmed that acemannan could induce maturation of immature DCs. Functional maturation of immature DCs was supported by increased allogeneic mixed lymphocyte reaction (MLR) and IL-12 production. The differentiation-inducing activity of acemannan was almost completely abolished by chemical sulfation. Based on these results, we propose that the adjuvant activity of acemannan is at least in part due to its capacity to promote differentiation of immature DCs.

Acemannan, a beta-(1,4)-acetylated mannan, induces nitric oxide production in macrophage cell line RAW 264.7.

Ramamoorthy L, Kemp MC, Tizard IR.
Department of Veterinary Pathobiology, Texas A & M University , College Station 77843 , USA
Mol Pharmacol. 1996 Oct;50(4):878-84.

Acemannan is a polydispersed beta-(1,4)-linked acetylated mannan with antiviral properties. It is an immunomodulator, and studies in our laboratory have shown that it causes activation of macrophages. Inducible NO synthase is generally expressed after transcriptional induction and is known to mediate some of the cytotoxic action of activated macrophages. Acemannan, in the presence of interferon-gamma, greatly increased the synthesis of NO in RAW 264.7 cells. This increase was preceded by increased expression of mRNA for the inducible form of macrophage NO synthase. Preincubation with pyrrolidine dithiocarbamate inhibited the induction, indicating the involvement of nuclear factor-kappa B. These results suggest that acemannan causes the activation of macrophages by increasing the level of NO synthase at the level of transcription.

Evaluation of Antioxidant Potential of Aloe vera (Aloe barbadensis Miller) Extracts.

Hu Y, Xu J, Hu Q.
College of Food Science and Technology, Nanjing Agricultural University, Nanjing, PRC, and Department of Biology, Changshu College of Science and Technology, Changshu, PR China.
J Agric Food Chem. 2003 Dec 17;51(26):7788-91.

The polysaccharide and flavonoid concentrations of two-, three-, and four-year-old Aloe vera were determined, and their antioxidant activities were evaluated compared to BHT and alpha-tocopherol by the DPPH radical scavenging method and the linoleic acid system at 100 microg of soluble solids per mL of ethanol. The results showed that three-year-old Aloe vera contained significantly higher levels of polysaccharides and flavonoids than two- and four-year-old Aloe vera, and no significant differences in flavonoid levels were found between three- and four-year-old Aloe vera. All the aloe extracts showed significant antioxidant activity. The antioxidant activity of Aloe vera extracts and reference compounds followed the order: three-year-old Aloe vera > BHT > four-year-old Aloe vera > alpha-tocopherol > two-year-old Aloe vera. The three-year-old extract exhibited the strongest radical scavenging activity of 72.19%, which is significantly higher than that of BHT at 70.52% and alpha-tocopherol at 65.20%. These data suggest that the growth stage plays a vital role in the composition and antioxidant activity of Aloe vera.

Isolation and characterization of the glycoprotein fraction with a proliferation-promoting activity on human and hamster cells in vitro from Aloe vera gel.

Yagi A, Egusa T, Arase M.
Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Hiroshima, Japan.
Planta Med. 1997 Feb;63(1):18-21.

Fractions of leaf gel from Aloe barbadensis Mill. were prepared by gel permeation using DEAE Sephadex A-25, Sepharose 6B, and Sephadex G-50 columns. These were then tested by in vitro assays for proliferation of human normal dermal and baby hamster kidney cells. The glycoprotein fraction promoted cell growth, while the neutral polysaccharide fraction did not show any growth stimulation. Moreover, the polar-colored glycoprotein fraction strongly inhibited the in vitro assays. An active glycoprotein fraction (protein 82%, carbohydrate 11%) examined on polyacrylamide gel electrophoresis (PAGE) and SDS-PAGE showed a single band. Its molecular weight was 29 kD on a Sephadex G-50 column and its isoelectric point was pH 6.8. Immunoblotting after SDS-PAGE showed that the glycoprotein was composed of two subunits (14 kD). Deglycosylation of glycoprotein (Pg21-2b fraction) by trifluoromethanesulphonic acid provided a protein band with a molecular weight of 13 kD on SDS-PAGE. The colored glycoprotein fraction was shown on SDS-PAGE to be a mixture with a molecular weight of 18 kD-15 kD. It was later hydrolyzed with 10% H2SO4 to produce phenolic substances.



Chemistry of natural compounds , 33(5)1997: 527-529

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