Preparative Paper Chromatography Research Articles

Biologically active compounds of Prunus spinosa L. mature fruits and prospects for their use

The article presents the results of determining the nutritional and biologically active components of the ripe fruits of prickly plum (Prunus spinosa L.), growing in Azerbaijan. It Magiera has been established that the fruits of the plant are rich in various nutritional and biologically active components, such as sugars, organic acids, pectin and tannins, flavonoids, anthocyanins and vitamin C. From simple sugars, fructose (2.82%), glucose (1.81%), sucrose (0.81%) and xylose (0.18%), citric, malic and succinic acids were identified in the composition of organic acids. In addition, the content of pectin were 2.3% and vitamin-C were 230 mg. The method of two-dimensional chromatography revealed 3 anthocyanidins in the sum of anthocyanins, identified as cyanidin-3-glucoside (chrysanthemin) and cyanidin-3,5-O-diglucoside (cyanine). Two individual substances were isolated by preparative paper chromatography, identified as quercitrin and rutin.

ФЛАВОНОИДЫ POLYGONUM HETEROPHYLLUM LINDM.

Виды горца Polygonum L. богаты различными биологически активными веществами – флавоноиды, катехины, антрахиноны, стильбены и др. Виды рода горец характеризуются высоким содержанием флавоноидных веществ, которые обладают антиоксидантыми, антимикробными, противовирусными, антиаллергическими, антиканцероген­ными, противоспалительными свойствами. Исследованы качественный состав и количественное содержание флавоноидов надземной части Polygonum heterophyllum. Методом двумерной бумажной хроматографии установлено, что экстракт из надземной части растений содержит 11 соединений полифенольной природы, 7 веществ дают характерную реакцию на флавоноиды. Методом препаративной хроматографии на бумаге в индивидуальном состоянии выделены два вещества, колоночной хроматографией на полиамиде – три вещества, два из которых являются агликонами, а три – гликозидами. На основании хроматографических и спектральных данных агликоны идентифици­рованы как кверцетин и лютеолин. По результатам кислотного гидролиза, а также хроматографических и спектраль­ных данных гликозиды идентифицированы как лютеолин-7-глюкозид, кверцетин-3-галактозид и кверцетин-3-арабинозид. Установлено, что в зависимости от местопроизрастания растений содержание флавоноидов изменяется в пределах 1,44–2,12% на воздушно-сухой вес сырья.

Anthocyanins from fruit of two species of the genus Rosa

We investigated the composition of anthocyanins from fruit of Rosa spinosissima L. and R. hracziana Tamam. (Rosaceae Juss.) growing near Bata-Bat, Shakhbuz Region, Republic of Azerbaidzhan. Fruit was collected on Sept. 16, 2009, during ripening. Freshly collected fruit (100 g each) was frozen with liquid N2 and pulverized. Pulp was separated from stones. Pulp (50 g each) was ground and extracted at room temperature for 2 d twice with EtOH (95%) and once with MeOH containing HCl (1%). The extracts were combined, filtered, and evaporated to dryness in vacuo at 30°C. The dry solid was treated with CHCl3 and then dissolved in MeOH (50 mL) containing HCl (0.5%). A part of the extract was hydrolyzed by HCl (2 N, 1:1 ratio) on a boiling-water bath for 60 min under reflux [1]. The hydrolysate was cooled. Aglycones were extracted by isoamyl alcohol for 20 h (shaking periodically). The isoamyl extract was studied by 2D chromatography on FN16 paper using Formic and Forestal systems [2]. Two aglycones were detected in the chromatogram. Preparative column chromatography using the Formic system isolated two pure aglycones. Aglycone-1 with Rf 0.32 (Formic) and 0.48 (Forestal) gave absorption maxima with fuchsine dye at 276 and 535 nm (MeOH containing 0.01% HCl). Adding AlCl3 produced a bathochromic shift of 20 nm. Aglycone-2 with Rf 0.12 and 0.31 (in the same systems, respectively) gave absorption maxima with purple dye at 277 and 546 nm. Addition of AlCl3 produced a bathochromic shift of 22 nm. Based on the chromatographic and spectral data and a comparison with authentic samples and the literature [2, 3], the first aglycone was identified as cyanidin; the second, delphinidin. Preparative 2D paper chromatography using n-BuOH:AcOH:H2O (4:1:2) (first direction) and AcOH:HCl (conc.):H2O (15:3:82) (second direction) showed that pulp of R. spinosissima fruit contained three; of R. hracziana, four anthocyanin glycosides. The first three components were identical in both species. Therefore, total anthocyanins from fruit pulp of R. hracziana was analyzed in detail. Preparative column chromatography (acidic cellulose powder) [4] and rechromatography on paper produced four pure anthocyanins. The pure anthocyanins were studied by chromatography and spectroscopy [2, 3, 5]. The anthocyanins were hydrolyzed as described above by neutralizing the hydrolysate with ion-exchange resin. Paper chromatography with authentic sugar samples identified D-glucose in hydrolysates of all glycosides. The chromatographic mobilities of anthocyanins 1 and 2 suggested that they were monoglucosides; 3 and 4, diglucosides. This agreed with results of stepwise acid analysis. The aglycone and sugar were cleaved after stepwise hydrolysis of anthocyanins 1 and 2 for 20 min. However, anthocyanins 3 and 4 formed four components. The first component corresponded to the starting glucoside; the second and third, to a monoglucoside; the fourth, the aglycone. The second spot did not fluoresce. Its Rf value indicated that it was the 3-glucoside. The third spot did fluoresce in UV light with emission analogous to the starting glucoside. It corresponded to the 5-glucoside according to fluorescence and chromatographic mobility. Oxidation of the anthocyanins with H2O2 produced glucose and confirmed that it was bonded to C3 in 1 and 2 and to C3 and C5 in 3 and 4 [1–3, 5, 6]. Thus, cyanidin-3-glucoside, cyanidin-3,5-diglucoside, delphinidin-3-glucoside, and delphinidin-3,5-diglucoside were identified for the first time in total anthocyanins from fruit pulp of R. hracziana using chromatography, spectroscopy, total and stepwise hydrolysis, oxidation by H2O2, and comparison with authentic samples. All components with the exception of delphinidin-3,5-diglucoside were found in R. spinosissima anthocyanidins. The monoglucosides of cyanidin and delphinidin dominated quantitatively the anthocyanin complex from fruit of both Rosa species.

Isolation and identification of a new flavonoid glycoside from Carrichtera annua L. seeds

Background:Flavonoids are a major group of constituents and are assumed to be among the beneficial components. Recently, they have also received considerable interest as components of foodstuffs and nutraceuticals because of their antioxidant and anticancer properties.Materials and Methods:About 500 g of air-dried powdered seeds of C. annua were defatted seeds and extracted with 70% methanol. The combined methanol extract was partitioned with chloroform and n-butanol. The butanol extract was concentrated and subjected to column chromatography on polyamide.Results:The fraction eluted with aqueous methanol (40% and 50%) was found to contain three main flavonoids (1, 2, and 3). Repeated column chromatography on polyamide and Sephadex LH-20 gave compound 1. Compounds 2 and 3 were further purified using preparative paper chromatography with 20% HOAc and Sephadex LH-20 column.Conclusions:Reinvestigation of the flavonoidal constituents of the butanol fraction of the aqueous methanolic extract of Carrichteraannua seeds led to isolation and identification of a new flavonoidal glycosidenamed as quercetin 3-O-[(6-sinapoyl-β-glucopyranosyl)-(1→2)-β-arabinopyranosyl]-7-O-β-glucopyranoside 1, in addition to, quarecetin-3-O-glucoside 2, isorhamnetin-3-O-β-runtinoside3, and isorhamnetin4.Structures of the isolated compounds were established by UV, MS, and 1H and 13C NMR.

Isolation, structural elucidation of flavonoid constituents from Leptadenia pyrotechnica and evaluation of their toxicity and antitumor activity

An investigation of Leptadenia pyrotechnica (Forsk.) Decne (Asclepiadaceace) chemical constituents led to the isolation of six flavonoids, kaempferol-3-O-α-l-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.1), kaempferol-3-O-β-d-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.2), texasin-7-O-β-d-glucopyranoside E-II.2, kaempferol-3-O-β-d-glucopyranoside (E-III.1), kaempferol (E-IV.1) and kaempferide-3-O-α-l-rhamnopyranosyl (1′″→6″)-O-β-d-glucopyranoside (E-I.1a). The isolation of these compounds was carried out using Sephadex LH-20 low pressure liquid chromatography (LPLC), preparative paper chromatography (PC), and high performance liquid chromatography (HPLC). The chemical structures of the isolated compounds were established by mass spectrometry (FAB- and EI- techniques), nuclear magnetic resonance NMR (1H-, 13C- and COSY) spectral data and ultraviolet (UV) spectroscopic techniques. The acute toxicity of total alcoholic and total flavonoid extracts were examined by brine shrimp. The LC50 values were 11.89 and 84.14 ppm for the total alcoholic and total flavonoid extracts, respectively. The mortality rates of the isolated flavonoid fractions of E-I, E-I.1, E-I.2 represent the higher percentages of mortality compared with the rest of the flavonoid fractions. The plant exhibited activity as an antitumor agent in the initial potato disc screen.

Phenolic and Terpenoid Constituents from the Sri Lankan Medicinal Plant Osbeckia aspera.

A crude aqueous acetone extract of Osbeckia aspera. Blume (Melastomataceae), a plant from Sri Lanka used traditionally to treat liver disease, was fractionated by column and preparative paper chromatography, and the fractions were analyzed by high-performance liquid chromatography (HPLC) using diode array and mass spectrometric detection. Phenolic acids (gallic, protocatechuic, and ellagic acid), flavonol glycosides [quercetin 3-O.-β-galactopyranoside, quercetin 3-O.-β-glucopyranoside, kaempferol 3-O.-β-glucopyranoside, and kaempferol 3-O.-(6″-O.-p.-coumaroyl-β-glucopyranoside) (tiliroside)] and flavonol aglycones (quercetin and kaempferol) were identified by comparison of their retention times, UV and MS spectra with those of authentic standards. Five compounds from a methanol extract were identified by NMR spectroscopy as the flavonol glycosides, quercetin 3-O.-(3″-O.-acetyl-β-galactopyranoside) and kaempferol 3-O.-[2″,6″-di-O.-(E.,E.)-p.-coumaroyl-β-glucopyranoside], and the norsesquiterpenoids 6,9-dihydroxy-4,7-megastig-madien-3-one, 9-hydroxy-4,7-megastigmadien-3-one and 9-hydroxy-4-megastigmen-3-one. A crude water extract, 50% acetone extract and fractions from this extract, a 100% methanol extract, and three of the phenolic acids in the fractions were tested for in vitro. hepatoprotective activity against bromobenzene and 2,6-dimethyl-N.-acetyl p.-quinoneimine toxicity to HepG2 liver-derived cells. The crude water extract showed protective activity against both liver toxins, whereas the fractions and compounds were more protective against 2,6-dimethyl-N.-acetyl p.-quinoneimine than bromobenzene. Of the three phenolic acids present in the extracts that were tested, gallic and protocatechuic acids were more active at protecting the liver cells from the two toxic compounds than ellagic acid.

Microwave-accelerated methylation of starch

A novel microwave-accelerated method for methylating soluble starch is described. Soluble starch could be fully methylated in 72% yield within 4.66 min using iodomethane and 30% potassium hydroxide under microwave irradiation. The completely methylated starch thus obtained was hydrolyzed with 60% HCO 2H for 1.5 min under 80% MW power, followed by 0.05 M H 2SO 4 for 2.0 min under 100% MW power. The partially methylated monosaccharides were separated by preparative paper chromatography and identified by their melting points and optical rotations.

Phytochemical and pharmacological studies on Convolvulus fatmensis Ktze.

Two aglycones flavonoid compounds were isolated from Convolvulus fatmensis Ktz. using column and preparative paper chromatography and identified by using 1 HNMR, 13 CNMR and UV shift reagent, these compounds were kaempferol and quercetin. Four coumarin compounds were isolated and identified as umbelliferone, scopoletin, asculetin and scopoline for the first time. Two phenolic acids were also isolated in the same manner and identified by spectroscopic methods, they are ferulic acid and caffeic acid. The methanol extract of Convolvulus fatmensis was evaluated for its potential antiulcerogenic, diuretic and hepatoprotective effects as well as for its acute toxicity. The antiulcerogenic effect was evaluated against acute (ethanol model) and prolonged (aspirin model)-gastric ulceration. The results revealed that, oral administration of the methanol extract (400 mg/kg bw) significantly reduced the alcohol-induced gastric ulcers (curative ratio; 32.6%). It also produced high curative ratio (75%), decreased the number of gastric ulcers, total acidity and total protein in aspirin-induced gastric ulcer (P < 0.05). Oral administration of 500 mg/kg bw methanol extracts did not affect the urine output, or sodium excretion while potassium and chloride excretion were significantly increased. The higher dose (1000 mg/kg bw) significantly increased the sodium, potassium and chloride excretion but did not affect urine volume. Moreover, it produced mild hepatoprotective effect against CCl 4 -induced hepatotoxicity as indicated from serum biochemical and histopathological changes. No signs of acute toxicity were observed after oral administration of doses up to 2.75 g/kg bw.

Phytochemical and biological investigation of Echium sericeum (Vahl) growing in Egypt

The genus Echium is represented in Egypt by seven species [1]. A number of naphthoquinones have been isolated from certain Echium species [2],[3]. The flavonoid constituents of certain Echium ssp. have been studied and a number of flavonoids were identified [4], as well as several pyrrolizidine alkaloids [5]. From the medical point of view, many Echium species are used in traditional Iranian medicine as tonic, tranquillizer, diaphoretic, cough suppressant and as a remedy for sore throat [6]. The present work deals with the study of the flavonoids of Echium sericeum and the evaluation of their insecticidal activity against Spodoptera littoralis (Boised) as well as the investigation of the anti-oxidant activity of both the total extracts and the isolated compounds, using the DPPH free radical assay. About 1kg of the aerial parts of E. sericeum were dried, powdered and extracted with petrol ether and then with 80% ethanol. After partition with chloroform, ethyl acetate and n-butanol the ethanolic extract yielded crude extracts containing flavonoids. These extracts were subjected separately to preparative paper chromatography (3MM, developed with 15% acetic acid) and the main flavonoid bands were cut and eluted separately with 90% methanol. The eluted fractions were further purified on a Sephadex LH-20 column. The isolated flavonoids were identified as apigenin, luteolin-7-O-rutinoside, apigenin-7-O-rhamnoside and quercetin-3-O-rhamnoside. Their identity was proven by TLC, PC, m.p., UV, 1H-NMR and FAB-MS. The ethyl acetate and n-butanol fractions as well as the four flavonoids isolated from the plant showed a strong antioxidant activity in the DPPH assay. The petrol ether extract of E. sericeum showed the strongest insecticidal activity against S. littoralis, causing 71.5% mortality, whereas the butanol and 80% alcoholic fractions also had a marked effect causing 62.5% mortality at a concentration of 2.5%, respectively.

Identification and Antioxidant Potential of Flavonoids and Low Molecular Weight Phenols in Olive Cultivar Chemlali Growing in Tunisia

Increasing interest in phenolic compounds in olives is due to their antioxidant and health-enhancing properties. In this study the phenolics in fruits of the Tunisian olive cultivar Chemlali were extracted by methanol-water and fractionated using Sephadex LH-20 column chromatography. The identification of phenolic monomers and flavonoids was based on separation by high-performance liquid chromatography equipped with a diode array detector followed by liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry analysis. Oleuropein, a secoiridoid glycoside esterified with a phenolic acid, was the major compound. Eight phenolic monomers and 12 flavonoids were also identified in Chemlali olives. Five flavonoids were isolated and purified using Sephadex LH-20 column chromatography and preparative paper chromatography. The antioxidant activity of the extract and the purified compounds was evaluated by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl and by using the beta-carotene-linoleate model assay. Acid hydrolysis of the extract enhanced its antioxidant activity. Hydroxytyrosol and quercetin showed antioxidant activities similar to that of 2,6-di-tert-butyl-4-methylphenol. A hydroxyl group at the ortho position at 3' on the B ring of the flavonoid nucleus could contribute to the antioxidant activity of the flavonoids.

Patterns of methyl and O-acetyl esterification in spinach pectins : new complexity

Driselase-digestion of cell walls from suspension-cultures of spinach ( Spinacia oleracea L.), followed by anion-exchange chromatography, gel-permeation chromatography, preparative paper chromatography and preparative paper electrophoresis, yielded ten uronic acid-containing products in addition to free galacturonic acid (GalA). These included 4- O-methylglucuronic acid, α- l-rhamnopyranosyl-(1→4)- d-glucuronic acid and several oligosaccharides containing GalA residues. The structures were unambiguously determined by a combination of 1- and 2-dimensional NMR spectroscopic techniques. Five of the six homogalacturonan-derived oligosaccharides purified contained 3- O-acetyl-GalA residues; however, methyl-esterified GalA residues occurred adjacent to both 2- O-acetyl-GalA and 3- O-acetyl-GalA residues. An acetylated, rhamnogalacturonan-I-derived oligosaccharide that was purified also contained 3- O-acetyl-GalA residues. Taken together with published data, our findings indicate considerable diversity in the patterns of pectin esterification. The implications for the action of pectin esterases are discussed.

Terihanine from Zanthoxylum nitidum

A phenolic quaternary 2,3,8,9-tetraoxygenated benzo[c]phenanthridine alkaloid, terihanine (3), was isolated by preparative paper chromatography (PPc) from the root bark of Zanthoxylum nitidum. From the phenolic tertiary base fraction of the stem bark, decarine (4), arnottianamide (5), toddaquinoline (6) and 6-carboxymethyl dihydrochelerythrine (7) were obtained. The presence of four quaternary benzo[c]phenanthridine alkaloids, terihanine (3), chelerythrine (8), avicine (9) and nitidine (10), in both the root bark and the stem bark was proved by preparative paper chromatography and TLC, but there was only trace amounts of terihanine (3) present in the stem bark.

Hydrolysis of wheat bran and straw by an endoxylanase: production and structural characterization of cinnamoyl-oligosaccharides

Hydrolysis of wheat bran and wheat straw by a 20.7 kDa thermostable endoxylanase released 35 and 18% of the cell-wall xylan content, respectively. Separation of the cinnamoyl-oligosaccharides (accounting for 6%) from the bulk of total oligosaccharides was achieved by specific anion-exchange chromatography. The cinnamoyl-oligosaccharides were further purified by preparative paper chromatography (PPC) and their molecular weight was determined by MALDI-TOF mass spectrometry. The partially purified hydrolysis end-products contained from 4 to 16 and from 4 to 12 pentose residues for wheat bran and straw, respectively, and only one cinnamic acid per molecule. The primary structure of the new feruloyl arabinoxylopentasaccharide from wheat bran hydrolysis, which has been determined using 2D NMR spectroscopy, is O-β- d-xylopyranosyl-(1→4)- O-[5- O-(feruloyl)-α- l-arabinofuranosyl-(1→3)]- O-β- d-xylopyranosyl-(1→4)- O-β- d-xylopyranosyl-(1→4)- d-xylopyranose.

Structure of xylan from culms of bamboo grass (Sasa senanensis Rehd.)

Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed withβ-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32-α-l-arabinofuranosyl-xylobiose, 32-α-l-arabinofuranosyl-xylotriose, 32-α-[β-d-xylopyranosyl-(1 → 2)-l-arabinofuranosyl]-xylobiose, 33-α-[β-d-xylopyranosyl-(1 → 2)-l-arabinofuranosyl]-xylotriose, 23-α-4-O-methyl-d-glucuronosyl-xylotriose, and 23-α-d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such asβ-d-xylopyranosyl-(1 → 2)-l-arabinofuranose.

NMR study of virenose and dihydrohydroxystreptose isolated from Coxiella burnetii phase I lipopolysaccharide

A lipopolysaccharide (LPS I) isolated from Coxiella burnetii in virulent phase I contains in its O-polysaccharide chain two unusual sugars, virenose (6-deoxy-3- C-methylgulose) and dihydrohydroxystreptose [3- C-(hydroxymethyl)lyxose]. The sugars were isolated from LPS I, after acid hydrolysis and removal of lipid A, by a combination of HPLC and preparative paper chromatography. Their enantiomeric forms and ring conformations were established from optical rotation and NMR data. Two-dimensional COSY, HSQC, and HMBC as well as one- and two-dimensional NOEs were used to assign all proton and carbon signals in both monosaccharides. Virenose was found to be the d- gulo enantiomer with the 4 C 1 ring conformation and dihydrohydroxystreptose was shown to be the l- lyxo enantiomer also with the 4 C 1 conformation. The latter sugar was reported [Š. Schramek, J. Radziejewska-Lebrecht, and H. Mayer, Eur. J. Biochem., 148 (1985) 455–461] to be present in LPS I in a furanose form, and it appears that a furanose to pyranose tautomerization took place in the course of the isolation procedure.

Structural Determination of Monosialyl Trisaccharides Obtained From Caprine Colostrum

Acidic oligosaccharides were separated by dialysis, ion-exchange, preparative paper and gel chromatography from caprine colostrum. Four sialyl trisaccharides were characterized by 1H-NMR spectrometry as follows: α- N-acetylneuraminyl-(2,6)- β- d-galactopyranosyl-(1,4)-2- N-acetamido-2-deoxy- d-glucopyranose (Neu5Ac α 2-6Gal β 1-4GlcNAc), α- N-acetylneuraminyl-(2,3)- β- d-galactopyranosyl-(1,4)- d-glucopyranose (Neu5Ac α 2-3Gal β-1-4Glc), α- N-acetylneuraminyl-(2,6)- β- d-galactopyranosyl-(1,4)- d-glucopyranose (Neu5Ac α 2-6Gal β 1-4Glc) and α- N-glycolylneuraminyl-(2,6)- β- d-galactopyranosyl-(1,4)- d-glucopyranose (Neu5Gc α 2-6Gal β 1-4Glc).

Identification of 2′-Fucosyllactose in Milk of the Crabeater Seal (Lobodon carcinophagus)

1. An oligosaccharide was isolated from extracts of crabeater seal milk by preparative paper chromatography. 2. The saccharide was identified as Fuc α 1–2Ga1 β 1–4G1c by 1H-NMR spectroscopy. 3. This work represents the first identification of an oligosaccharide, other than lactose, in the milk of a pinniped.

Oligosaccharides derived from the xyloglucan isolated from the seeds of Hymenaea courbaril var. stilbocarpa

On aqueous extraction, Hymenaea courbaril var. stilbocarpa, known in Brazil as jatobá, furnishes a high yield of viscous xyloglucan (45%) from its seeds. The crude polysaccharide (B1) was hydrolysed and the products, analysed as alditol acetates, were glucose, xylose, galactose and arabinose in the ratio 50:35:13:2. After further fractionation on a DEAE-cellulose column (chloride form), the main fraction (70% yield, B2) was obtained. The basic structure of the xyloglucan was determined as a cellulose-type (1 → 4)-linked β- d-glucan backbone partially substituted with side chains at 06 of α- d-xylopyranose, some of which were themselves substituted at 02 by the units of β- d-galactopyranose. Treatment of the xyloglucan (B2) with commercial cellulase from Trichoderma sp. yielded six oligosaccharides. These oligosaccharides were isolated by preparative paper chromatography, and their structures were determined by gas-liquid chromatography-mass spectroscopy of the derived partially O-methylated alditol acetates. These results confirm the structure proposed for jatobá seed xyloglucan.

Sequencing of xyloglucan oligosaccharides by partial Driselase digestion: the preparation and quantitative and qualitative analysis of two new tetrasac

The pentasaccharide (XXG), ▪ obtained from Rosa xyloglucan, was converted to two isomeric tetrasaccharides, a and b (Xyl 1·Glc 3), by mild acid hydrolysis. During hydrolysis in 2 M trifluoroacetic acid at 90°C, optimal yields of a and b were obtained after 20–40 min. Each tetrasaccharide was purified by preparative paper chromatography and high-pressure liquid chromatography (HPLC). The two isomers were distinguished by the products of their partial digestion with Driselase, which hydrolyses the glucosidic bonds sequentially from the non-reducing terminus: a and b yielded cellobiose and Xyl → Glc → Glc, respectively, showing that they were ▪ and ▪, respectively. Tetrasaccharide b was chromatographically identical, upon HPLC on Dionex CarboPac PA1, with the tetrasaccharide produced from XXG by the action of Tropaeolum

Formation of beta-galactosyl compounds of arabinosylcytosine in growing culture of Sporobolomyces singularis.

Two new compounds of 1-beta-D-arabinofuranosylcytosine (ara-C) were found to be produced in a high yield in a culture filtrate of Sporobolomyces singularis, when grown on a medium containing lactose and ara-C. The compounds I and II were obtained as white needle crystals from the culture filtrate by preparative paper chromatography, gel-filtration on Sephadex G-10 and Toyopearl HW-40S, lyophilization, and ethanol treatment. The compounds I and II were identified as 3'-O-(beta-D-galactopyranosyl)-ara-C and 3'-O-[beta-D-galactopyranosyl-(1-->4)-O-beta-D-galactopyranosyl]-ara-C, respectively, on the basis of the various experimental results, viz., elementary analyses, UV, IR, 1H-, and 13C-NMR spectra, and products by hydrolysis with alpha- and beta-galactosidases. Also, the yeast produced a large amount of 3'-O-beta-galactosyl compounds of adenosine and inosine in the culture filtrate when grown on a medium containing lactose and their ribonucleosides.