Screening assay for glycosyltransferase activities.

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... CLC method was checked also by 1 H NMR. It measured different fractions collected from flow out separated of the mixture reagents and spectrums were compared with above standard spectrums. The high resolution 1 H NMR spectra of pure model compounds and fraction 1-3 are shown in Figure 2. ...

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... {Fuc-β-pNp}; 4-Nitrophenyl α-D-mannopyranoside {Man-α-pNp}; and 4- Nitrophenyl β-D-mannopyranoside {Man-β-pNp}), and bacterial lysate described in 2.1 as the enzyme sample. An example of results obtained by using this method is shown in Figure 2. High levels of radioactivity were observed in the eluates from the reaction mixture of samples #1 and #8, respectively, when the reaction was performed in the presence of acceptor substrate. ...

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... clarify which of the glycosyltransferase activities the bacteria displayed, the enzymatic reaction was performed independently with each of the donor substrates in turn. The two bacteria that showed glycosyltransferase activity in Figure 2 were shown to specifically produce fucosyltransferase. ...

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... ( Kleemann & Engel, 2005;Evers et al., 2005). Thus, the N-aryl imine 6, the main and value starting, can be prepared from commercially available 3-indolaldehyde 4 and 2-cyanoaniline 5, according to published methods ( Colyer et al., 2006). This aldimine is obtained as a white and stable solid after purification by recrystallization in 95 % yield (Fig. 2). The method employed to obtain the precursor 7, is one of the most known procedures to reduce an aldimines with an excess of NaBH 4 in methanol, protocol that is still the reaction of choice to produce secondary amines in reasonably good yield. Thus, N-(2-cyanophenyl)-N-(3-indolylmethyl)amine 7 is prepared as was described and was ...

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... as white solid in 70 % yield after purification through recrystallization ( Bello et al., 2010). This example, in which the main precursor is prepared in a linear process and purified by recrystallization, represents an excellent technique that avoids the loss of value material and it will be increase the global yields of the final product. Fig. 2. Synthesis and reduction of the aldimine 6 to give the desired secondary amine 7 in excellent overall ...

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... crude alcoholics or hidroalcoholics extracts obtained from parts of the plant material, two methods already described in the literature may be used for preliminary extraction of alkaloids; both methods take into account the basic nature of these compounds in order to concentrate them in pKas nearby and produce more purified fractions, preceding the phases of isolation and identification of substances. The first method consists of a complete acid- base partition (Figure 2), employing solvents such as chloroform or dichloromethane, Fig. 2. Complete acid-base extraction from crude extract of A. ramiflorum. ...

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... both methods take into account the basic nature of these compounds in order to concentrate them in pKas nearby and produce more purified fractions, preceding the phases of isolation and identification of substances. The first method consists of a complete acid- base partition (Figure 2), employing solvents such as chloroform or dichloromethane, Fig. 2. Complete acid-base extraction from crude extract of A. ...

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... purified compound was extracted from the silica with chloroform. Two clear singlets in the aromatic hydrogens at 6.56 and 6.94 ppm instead of a doublet pointed to a 7-hydroxy-substituted structure ( Figure 2). Chemical shifts were in good agreement with published data for cis-7-hydroxycalamene. ...

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... were identified as lutein-5,6-epoxide, (9Z)-lutein-5,6-epoxide, (9Z,9'Z)-lutein (neolutein C), (9Z)-and/or (9'Z)-lutein (neolutein B) and (13Z)-and/or (13'Z)-lutein (neolutein A), in addition to (all-E)-lutein, violaxanthin, (9Z)-violaxanthin, flavoxanthin and/or chrysanthemaxanthin ( Horvath et al., 2010). Xanthophylls, such as 5,6-diepikarpoxanthin, mutatoxanthin, anteraxanthin, zeaxanthin, β-cryptoxanthin and apo-carotenoids, such as capsorubin, capsochrome, capsanthin 5,6-epoxide and capsanthone, were also isolated from Asparagus falcatus using CaCO 3 as adsorbent on CC (Deli et al, 2000). The isomers of β-carotene present in acetone extracts from Malpighia glabra pulp (Agostini-Costa et al, 2003) and from Annona coriaceae fruit ( Agostini et al., 1996) were separated on Ca(OH) 2 CC eluted with 2% ethyl ether in petroleum ether. ...

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... obtained from 20% aqueous ethanol was further purified on TSK Toyopearl HW-40 (S) CC developed with aqueous ethanol 0 to 20% to get the purified new compound established as 3-o-galloyl quinic acid butyl ester (Figure 11) (He et al., 2009). Polyamide CC eluted with water and 50%, 70% and 100% aqueous methanol further facilitated GC-MS and HPLC separation of phenolic compounds in Euphrasia rostkoviana (Blazics et al., 2008). ...

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... collected in Okinawa, Japan. Named respectively, nakijinamines C and E (Figure 20), they constitute a group of heteroaromatic alkaloids, hybrids of aaptamine-type and bromoindole alkaloids (Takahashi et al., 2011). Other 23 aaptamine-type alkaloids have been isolated so far, but none contain the hybrid ring system. ...

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... purification on Sephadex LH-20, the methanolic extract of Eudistoma glaucus was chromatographed on a silica gel column with hexane-ethyl acetate mixtures, and then on another column with amino silica gel, also eluted with the same solvents. Normal phase HPLC led to the isolation of eudistomidin H ( Figure 22) and eudistomidin I. Eudistomidins H and I were new compounds containing a unique fused-tetracyclic ring system consisting of a tetrahydro β- carboline ring and a hexahydropyrimidine ring. Using the same stationary phases, but changing the solvent system to chloroform-methanol, eudistomidin K was obtained. ...

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... compounds come off the column, they enter a detector for identification. Figure 2 represent the carbon number range distribution of common hydrocarbons in crude oil and petroleum products. ...