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The analytical procedures for determining plant constituents involve the application of sample preparation methods to fully isolate and/or pre-concentrate the analyzed substances. High-temperature liquid extraction is still applied most frequently for this purpose. The present paper shows that high-temperature extraction cannot be applied for the analysis of chlorogenic acids (CQAs) and their derivatives in plants as it causes the CQAs transformation leading to erroneous quantitative estimations of these compounds. Experiments performed on different plants (black elder, hawthorn, nettle, yerba maté, St John's wort and green coffee) demonstrate that the most appropriate method for the estimation of CQAs/CQAs derivatives is sea sand disruption method (SSDM) because it does not induce any transformation and/or degradation processes in the analyzed substances. Owing to the SSDM method application we found that the investigated plants, besides four main CQAs, contain sixteen CQAs derivatives, among them three quinic acids. The application of SSDM in plant analysis not only allows to establish a true concentration of individual CQAs in the examined plants but also to determine which chlorogenic acids derivatives are native plant components and what is their concentration level. What is even more important, the application of SSDM in plant analysis allows to eliminate errors that may arise or might have arisen in the study of chlorogenic acids and their derivatives in plant metabolism., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

To determine if atrial natriuretic peptides are present in plants as well as animals, where they are important for water and sodium metabolism, the leaves and stems of the Florida Beauty (Dracena godseffiana) were examined. The N-terminus consisting of amino acids (a.a.) 1-98 (i.e., pro ANF 1-98), the mid portion of the N-terminus (a.a. 31-67; pro ANF 31-67), and C-terminus (a.a. 99-126; ANF) of the 126 a.a. atrial natriuretic factor (ANF) prohormone were all present in the leaves and stems of this plant. The concentrations of pro ANF 1-98, pro ANF 31-67 and ANF-like peptides of 120 +/- 20, 123 +/- 21, and 129 +/- 20 ng/g of plant tissue in leaves and 109 +/- 20, 96 +/- 21, and 124 +/- 18 ng/g of tissue, respectively, in the stems were lower (P less than 0.05) than their concentrations in rat (Rattus norvegicus) heart atria of 196 +/- 40, 192 +/- 28, and 189 +/- 15 ng/g of tissue respectively, but higher (P less than 0.001) than their respective concentrations of 4.3 +/- 1.4, 4.1 +/- 1.2, and 3.9 +/- 1 ng/g of rat heart ventricular tissue. We conclude that the atrial natriuretic peptide-like hormonal system is present in the plant kingdom as well as in the animal kingdom.

High-performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD) under alkaline conditions (pH 9-13) separates aminosaccharides, neutral saccharides and glycuronic acids based upon their molecular size, saccharide composition and glycosidic linkages. Carbohydrates were extracted by utilizing 0.5 M H2SO4 (neutral monosaccharides), 0.25 M H2SO4 coupled with enzyme catalysis (glycuronic acids) and 3 M H2SO4 (aminosaccharides). Solid-phase extraction with strong cation and strong anion resins was used to partition the cationic aminosaccharides and anionic glycuronic acids and to deionize acid extracts for neutral saccharides. Separation was conducted on a medium-capacity anion-exchange column (36 mequiv.) utilizing sodium hydroxide (5-200 mM and sodium acetate (0-250 mM) as the mobile phase. The saccharides were detected by oxidation at a gold working electrode with triple-pulsed amperometry. HPAEC-PAD was found superior to high-performance liquid chromatography with refractive index (RI) detection for neutral monosaccharides and aminosaccharides and to low-wavelength UV detection for glycuronic acids in terms of resolution and sensitivity. HPAEC-PAD was not subject to interferences as was the case for low UV detection (210 nm) or RI analyses and was highly selective for mono- and aminosaccharides and glycuronic acids. The use of HPAEC-PAD was applied for the determination of the saccharide composition of organic materials (plant residues, animal wastes and sewage sludge), microbial polymers and soil.

C22:1 omega 5-anacardic acid was found to be a good inhibitor of both potato lipoxygenase and ovine prostaglandin endoperoxide synthase with approximate IC50's of 6 and 27 microM, respectively. Very similar inhibition was seen with the crude exudate, rich in omega 5-anacardic acids, from glandular trichomes of an arthropod-resistant strain of geranium, Pelargonium xhortorum. The saturated anacardic acid (C22:0 sat), abundant in the trichome exudate of susceptible strains, was nearly as inhibitory toward both prostaglandin endoperoxide synthase and lipoxygenase as the omega 5-unsaturated compound. However, the dimethyl derivative of C22:1 omega 5-anacardic acid was a poor inhibitor of prostaglandin endoperoxide synthase and caused only moderate (32%) inhibition of lipoxygenase even at 135 microM. The possible role of prostaglandin endoperoxide synthase and lipoxygenase inhibition in the enhanced pest resistance of geraniums which produce the omega 5-AnAs is discussed.

The effects of I- ions on O2 evolution by photosystem 2 particles, which were depleted of the 18-kDa and the 23-kDa extrinsic proteins of the O2 evolution complex by NaCl washing (dPS2 particles) were examined. In the absence of Cl- (incompetent dPS2) I- stimulated O2 evolution up to 3-6 mM, depending on the associated cation, and inhibited it at higher concentrations. In the presence of Cl- (competent dPS2), I- was inhibitory at all concentrations. The inhibition was reversible, it occurred at a site preceding Tyrz (Tyr residue mediating electron transfer from H2O to photosystem 2), and it interfered noncompetitively with the reactivation of incompetent dPS2 with Cl-. Furthermore, the organic salts tetrabutyl ammonium iodide and tetraphenyl phosphonium iodide proved to be stronger inhibitors than the inorganic NaI. This is interpreted as an indication of a negatively charged surface, situated behind a hydrophobic permeability barrier. Permeant organic cations, being better compensators of the inner surface charge than Na+, are also more apt in facilitating access of the I- ions to the inhibitory site in the vicinity of Tyrz.

Omega-3 Fatty acids (omega-3FAs) are found in seafoods, some plants, and some livestock rations. Fish oils are the only concentrated source of eicosapentaenoic acid (EPA; 20:5 omega-3) and docosahexaenoic acid (DHA; 22:6 omega-3). The major omega-3FA in plants is alpha-linolenic acid (LNA; 18:3 omega-3). LNA must be converted to EPA before it exerts biological effects similar to EPA, such as reduced platelet aggregation. Human beings convert LNA to EPA to a small extent only. LNA may be more readily oxidized than incorporated into tissues. The effects of consuming LNA-rich oils are more modest than the effects of EPA-rich oils. Evidence suggests that omega-3FAs are essential and highly desirable for brain and eye development and heart health. LNA is the only source of omega-3FAs for vegetarians. Because LNA and EPA are not biologically equivalent, food composition data or product claims mentioning total omega-3FA content must clarify the individual omega-3FAs present.

The water-soluble polysaccharides from dried Ginkgo biloba leaves were isolated after exhaustive extraction with organic solvents. The polysaccharide mixture could be separated into a neutral (GF1) and two acidic (GF2 and GF3) polysaccharide fractions by ion exchange chromatography. According to the Mr distribution GF1 and GF3 seemed to be homogenous, whereas GF2 could be further fractionated into two subfractions (GF2a and GF2b) by gel permeation chromatography. GF1 (Mr 23,000) showed the structural features of a branched arabinan. The main chain was composed of 1,5-linked arabinose residues and three in 12 arabinose molecules were branched via C-2 or C-3. GF2a (Mr 500,000) consisted mainly of 1,2,4-branched mannose (29%), 1,4-linked glucuronic (32%) and galacturonic (8%) acid as well as terminal rhamnose (25%). After removal of ca 70% of the terminal rhamnose the remaining polysaccharide showed a decrease in 1,2,4-branched mannose and an increase in 1,2-linked mannose indicating that at least half of the rhamnose residues were linked to mannose via C-4. GF3 (Mr 40,000) consisted of 1,4-linked galacturonic (30%) and glucuronic (16) acid, 1,3,6-branched galactose (15%), 1,2-linked (5%) and 1,2,4-branched (3.5%) rhamnose as well as 1,5-linked arabinose (11%). Rhamnose (5%) and arabinose (10%) were present as terminal groups. Mild acid hydrolysis selectively cleaved arabinose and the remaining polysaccharide showed an increased amount of 1,6-linked and terminal galactose and a decreased quantity of 1,3,6-branched galactose. These results indicated that the terminal as well as the 1,5-linked arabinose were mainly connected to galactose via C-3. The GF3 polysaccharide appeared to be a rhamnogalacturonan with arabinogalactan side chains.

The structures of the new steroidal saponins (tentatively named YS-XI, -XII and -XIII) have been isolated from the caudex of Yucca gloriosa and characterized as 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-galactopyranosyl 5 beta- (25R)-spirostan-3 beta, 12 beta-diol, 3-O-beta-D-glucopyranosyl-(1----2)- [beta-D-glucopyranosyl-(1----3)]-beta-D-glucopyranosyl 5 beta- (25R)-spirostan-3 beta, 12 beta-diol and 3-O-beta-D-glucopyranosyl-(1----2)- beta-D-galactopyranosyl 5 beta-(25R)-spirostan-2 beta,3 beta,12 beta-triol, respectively.

Four new saponins were isolated from the alcoholic extract of the bark of Cylicodiscus gabunensis by means of flash chromatography. They were characterized on the basis of spectral and chemical data as 3-O-beta-[alpha-L-arabinopyranosyl (1----2),alpha-L-arabinopyranosyl(1----3),beta-D-glucopyranosyl(1- ---)] maslinic acid-28-[beta-D-glucopyranosyl(1----6),beta-D-glucopyranosyl(1----2),alp ha-L- rhamnopyranosyl(1----)] ester; 3-O-beta-[alpha-L-arabinopyranosyl(1----2),alpha-L-arabinopyran osyl (1----3),beta-D-glucopyranosyl(1----)]maslinic acid-28-[beta-D-glucopyranosyl(1----2),alpha-L-rhamnopyranosyl(1----)] ester, 3-O-beta-[alpha-L-arabinopyranosyl(1----2),alpha-L-arabinopyran osyl (1----3),beta-D-glucopyranosyl(1----)]maslinic acid and 3-O-beta(alpha-L-arabinopyranosyl(1----3),beta-D-glucopyranosyl (1----)] cylicodiscic acid.

From the nutrition medium of Arnica montana cell cultures two homogeneous polysaccharides, an acidic arabino-3,6-galactan-protein with mean Mr of 100,000 and a neutral fucogalactoxyloglucan with mean Mr of 22,500 have been isolated by DEAE-Sepharose CL-6B and Sephacryl S-400 column chromatography. Their structures were elucidated mainly by methylation analysis, partial acidic and enzymatic hydrolysis and 13C NMR spectroscopy. The fucogalactoxyloglucan shows a pronounced enhancement of phagocytosis in vivo. The arabino-3,6-galactan-protein displays a strong anticomplementary effect and stimulates macrophages to excrete the tumour necrosis factor (TNF alpha).

The major inhibitor of trypsin in seeds of Prosopsis juliflora was purified by precipitation with ammonium sulphate, ion-exchange column chromatography on DEAE- and CM-Sepharose and preparative reverse phase HPLC on a Vydac C-18 column. The protein inhibited trypsin in the stoichiometric ratio of 1:1, but had only weak activity against chymotrypsin and did not inhibit human salivary or porcine pancreatic alpha-amylases. SDS-PAGE indicated that the inhibitor has a Mr of ca 20,000, and IEF-PAGE showed that the pI is 8.8. The complete amino acid sequence was determined by automatic degradation, and by DABITC/PITC microsequence analysis of peptides obtained from enzyme digestions of the reduced and S-carboxymethylated protein with trypsin, chymotrypsin, elastase, the Glu-specific protease from S. aureus and the Lys-specific protease from Lysobacter enzymogenes. The inhibitor consisted of two polypeptide chains, of 137 residues (alpha chain) and 38 residues (beta chain) linked together by a single disulphide bond. The amino acid sequence of the protein exhibited homology with a number of Kunitz proteinase inhibitors from other legume seeds, the bifunctional subtilisin/alpha-amylase inhibitors from cereals and the taste-modifying protein miraculin.

Three flavonoids and three saponins have been isolated from Oxytropis species. Their structures were determined as isorhamnetin-3-O-beta-D-glucoside, rhamnetin-3-O-beta-D-galactoside, apigenin, 3-O-[alpha-L-rhamnopyranosyl (1----2)-beta-D-glucopyranosyl(1----4)-beta-D-glucuronopyranosyl]+ ++soyasapogenol B, 3-O-[beta-D-glucopyranosyl(1----2)-beta-D-glucuronopyranosyl] azukisapogenol and a new saponin 3-O-[beta-D-glucopyranosyl(1----2)-beta-D-glucopyranosyl]-25-O-alpha-L- rhamnopyranosyl-(20S,24S)-3 beta,16 beta, 20,24,25-pentahydroxy-9,19-cycloanostane.

Eight new steroidal glycosides, tentatively named YS-VI, -VII, -VIII, -IX, -X, -XI, -XII and -XIII were isolated from the caudex of Yucca gloriosa along with P-1, YG-2 and YG-3 previously obtained from flowers. The structures of five of these compounds were elucidated as mexogenin 3-O-beta-D-glucopyranosyl-(1----2)-beta-D-galactopyranoside (YS-VI), gloriogenin 3-O-beta-D-glucopyranosyl-(1----2)-[beta- D-glucopyranosyl-(1----3)]-beta-D-glucopyranoside (YS-VII) and 3-O-beta-D-glucopyranosyl-(1----2)-[beta-D-glucopyranosyl)-(1----3)]- beta-D-galactopyranoside (YS-VIII), manogenin 3-O-beta-lycotetraoside (YS-IX) and 3-O-alpha-L-rhamnopyranosyl-beta-lycotetraoside (YS-X), respectively, on the basis of chemical and spectral evidence.

Chemical examination of the methanolic extract of the roots of Cassia pudibunda led to isolation of the new rubrofusarin-6-O-beta-D-glucopyranoside, quinquangulin-6-O-beta- D-apiofuranosyl-(1----6)-O-beta-D-glucopyranoside, quinquangulin-6-O-beta-D-glucopyranoside and chrysophanol dimethyl ether. Moreover the known chrysophanol, physcion, cis-3,3',5,5'-tetrahydroxy-4-methoxystilbene, trans-3,3',5,5' -tetrahydroxy-4-methoxystilbene, and cassiaside B were identified. The antimicrobial activity of some of these compounds is also reported.

Using a bioassay for inhibition of plant growth and a combination of two countercurrent chromatographies: rotation locular countercurrent chromatography and droplet countercurrent chromatography, two biologically active glycosidal alkaloids, solasonine and solamargine were isolated from fresh ripe fruit of Solanum incanum. The combination of these chromatographic techniques has established an efficient isolation of polar phytochemicals of steroidal glycoalkaloids.

A new phenylpropanoid glycoside, pedicularioside A, and five known glycosides, acteoside, isoacteoside, decaffeoylacteoside, echinacoside and 8-acetylharpagide, were isolated from whole plants of Pedicularis striata. On the basis of spectral and chemical evidence, pedicularioside A was shown to be 1'-O-beta-D-(3,4-dihydroxy-beta-phenyl)-ethyl-4'-O-caffeoyl-beta-D -apiosyl-(1----3')-alpha-L-rhamnosyl-(1----6')-glucopyranosi de.

The novel diglycosyldiacylglycerol (DGDG), galactosyl(beta 1----6)-galactosyl(beta 1----3')-diacylglycerol (B isomer), present in Adzuki beans was found to be distributed together with the well-known galactosyl(alpha 1----6)-galactosyl(beta 1----3')-diacylglycerol (A isomer), in all (10) of the higher plants examined. The highest levels were found in leguminous seeds were the amounts were always less than 33% of the total DGDG of mature seeds. The highest proportion of the B isomer was found in Adzuki bean seed DGDG (26-33%), with the lowest in pea seed DGDG (2%). The amounts of the B isomer in DGDG of Adzuki and kidney beans cotyledons were almost equal to those in mature seeds. Immature seeds and hypocotyls of three kinds of beans also contained the B isomer in small amounts compared with the mature beans, while only trace amounts of the isomer was found in other organs such as leaves, stems, pods, roots and generative organs of plants, except for root from kidney beans. The molecular species composition of the principal diacylglycerol moieties in the A and B isomers of DGDG were found to be significantly different among several plant seeds, although the component diacylglycerol species were qualitatively similar to each other.

A new cardenolide tetraglycoside, oxyline, was isolated from the dried roots of Oxystelma esculentum. On the basis of chemical and spectroscopic evidence the structure of oxyline was established as 3-epi-uzarigenin-3-O-beta-D-cymaropyranosyl-(1----4)-O-beta- D-thevetopyranosyl-(1----4)-O-beta-D-cymaropyranosyl- (1----4)-O-beta-D-digitoxopyranoside.

The levels of mercury in water, soil, plants, poultry and poultry products, fish, dustfall as well as in total daily diet of apprentices were measured. The main purpose of our study was to estimate the average daily intakes of mercury.

A multimedia transport model was used to evaluate the environmental partitioning of benzene. Measured and predicted environmental concentrations were used to estimate the accumulation of benzene in the food chain and the subsequent extent of human exposure from inhalation and ingestion. Results show that benzene partitions mainly into air (99.9%) and that inhalation is the dominant pathway of human exposure, accounting for more than 99% of the total daily intake of benzene. Ingestion of contaminated food items represents only a minor pathway of human exposure. The long-term average daily intake of benzene by the general population of the U.S. was estimated using three independent methods. Intake estimates based on measured personal air exposures, measured exhaled air concentrations, and a pharmacokinetically derived adipose tissue concentration (73, 63, and 72 micrograms/day, respectively) are in good agreement. Although inhalation is the primary route of human exposure to background levels of benzene in the environment, smoking was found to be the largest anthropogenic source of background human exposure to benzene.

In this report we have compared the lectin-like properties of Pertussis toxin with two plant lectins which are known to possess different specificities towards terminal Neu5Ac Gal linkages on glycoconjugates. The hemagglutinin from elderberry bark (Sambucus nigra) has a binding specificity for terminal Neu5Ac alpha (2-6) Gal sequences and was found to bind a series of glycoconjugates with a similar specificity as Pertussis toxin. The binding specificity of Pertussis toxin was different from that of the leukoagglutinin from the seeds of Maackia amurensis which preferentially binds terminal Neu5Ac alpha (2-3) Gal sequences. These observations confirm the specificity of Pertussis toxin for Neu5Ac alpha (2-6) Gal glycoconjugate sequences.

A procedure for the carbohydrate analysis of glycoproteins electrotransferred to a polyvinylidene difluoride membrane is described. The glycoproteins (plant lectins, transferrin, and vitronectin) were first separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and then electroblotted onto a membrane. Each of the glycoprotein bands visualized by staining with Coomassie brilliant blue R-250 was excised from the membrane and subjected to direct hydrolysis either in 2.5 M trifluoroacetic acid at 100 degrees C for 6 h for neutral sugars and hexosamines, or in 0.05 M H2SO4 at 80 degrees C for 1 h for sialic acids. The hydrolysate obtained was analyzed for neutral sugars, hexosamines, and sialic acids independently by three different systems of high-performance liquid chromatography. The analytical values were reproducible with reasonable accuracy and agreed with those expected with recoveries of 57-66%. The method was successfully applied to a mannose-specific lectin of Sophora japonica bark, which is composed of four different subunits that aggregate sugar specifically. Because the four subunits could be separated by SDS-PAGE alone, the method proved useful for determining their carbohydrate compositions. Three of them were shown to contain carbohydrates typical of N-linked oligosaccharides of plant origin, which agreed well with the results of the binding assay carried out on a membrane using various horseradish peroxidase-labeled lectins.

Hydrolysis of bamboo shoot cell walls with Driselase (a fungal enzyme preparation) gave xyloglucan and arabinoxylan oligosaccharides containing ferulic and p-coumaric acids, respectively. The structures of two oligosaccharides containing phenolic acids are here determined to be O-(4-O-trans-feruloyl-alpha-D-xylopyranosyl)-(1----6)-D-glucopy rano se and O-[5-O-(trans-p-coumaroyl(-alpha-L-arabinofuranosyl]-(1----3)-O-be ta-D-xylopyranosyl-(1----4)-D-xylopyranose, on the basis of n.m.r. spectroscopy, methylation analysis, and f.a.b.-m.s. The possible role of phenolic acid substituents in cell-wall architecture is discussed.

A seed globulin from Vicia narbonensis L. has been crystallized by vapour diffusion induced pH-shift. Crystals are suitable for high-resolution X-ray structural analysis and diffract to better than 1.5 A. Narbonin crystallizes in the monoclinic space group P21 with alpha = 46.9 A, b = 75.5 A, c = 50.9 A, alpha = gamma = 90 degrees, beta = 120.5 degrees. The protein consists of one polypeptide chain that does not coincide with the subunits of legumin or vicilin after SDS/polyacrylamide gel electrophoresis and has a relative molecular mass of about 33,000.

Condensation of allyl 3,4-di-O-benzyl-beta-D-xylopyranoside with 2-O-acetyl-3,4,6-tri-O-benzyl-alpha-D-galactopyranosyl chloride in dichloromethane in the presence of silver triflate gave allyl 2-O-(2-O-acetyl-3,4-6-tri-O-benzyl-beta-D-galactopyranosyl)-3,4-di-O benzyl-beta-D-xylopyranoside (7, 83%). Compound 7 was converted in five steps into 2-O-(2-O-acetyl-3,4-6-tri-O-benzyl-beta-D-xylopyranosyl bromide (13), which was condensed immediately with allyl 2,3,6-tri-O-acetyl-4-O-(2,3,di-O-acetyl-beta-D-glucopyranosyl)-beta-D- glucopyranoside to give crystalline allyl O-(2-O-acetyl-3,4,6-tri-O-benzyl-beta-D-galactopyranosyl)- (1----2)-O-(3,4,-di-O-benzyl-alpha-D-xylopyranosyl)-(1----6)-O-(2,3,-di- O-acetyl-beta-D-glucopyranosyl)-(1----4)-2,3,6-tri-O-acetyl-beta-D-gluco pyranoside (23, 50%). O-Deacylation of 23 followed by catalytic hydrogenolysis gave the title glycoside.

Three bark lectins were isolated from elderberry Sambucus sieboldiana using fetuin-Sepharose 4B and mucin-Sepharose 4B, and were studied comparatively for their binding to glycoprotein and to clarify various physicochemical features. For each, a unique pattern on isoelectric focusing was noted and their affinity toward various glycoproteins differed, indicating the structures of their carbohydrate binding sites possibly differ. One bark lectin showed specific binding toward porcine mucin. The purity of mucin from a crude porcine stomach mucin or an extract of porcine submaxillary glands could be improved by affinity chromatography on immobilized lectin having binding specificity toward mucin.

This paper considers some features of the production of phosphorus fertilizers in relation to pollution of the environment by rare-earth elements by measuring the change in the rare-earth elements interrelationship in snow. The main source of the pollution is identified. The distribution of pollutants is dependent on the size of the associated aerosol particles. We also report data on the concentrations of the pollutants in agricultural plants, employees' hair and hair of local residents.

Octadecyl porous glass was used as the packing for reversed-phase high-performance liquid chromatography. A mixture of ginsenosides and saikosaponins (saponins of ginseng and bupleurum root, respectively) were analysed with detection at 203 nm. A well resolved chromatogram of ginsenoside Rb1, Rc, Rb2 and Rd and saikosaponin a, b2 and c was obtained with acetonitrile-water (25.5:74.5) as the mobile phase. The whole separation was achieved in 20 min with a flow-rate of 1.5 ml/min. Calibration graphs for ginsenoside Rb1, Rc, Rb2 and Rd and saikosaponin a and c were linear up to 5 micrograms. Rapid and accurate simultaneous determinations of the saponins are possible by the described method.

A main acidic polysaccharide preparation was isolated from the leaves of Malva sylvestris L. var mauritiana Mill. It is composed of L-rhamnose, D-galactose, D-galacturonic acid, and D-glucuronic acid in the molar ratio of 22:6:22:11, and it contains 7.7% peptide. It was homogeneous by electrophoresis and gel chromatography, which gave a value of 11,000 as molecular weight. The structure of the polysaccharide component was elucidated by methylation analysis and partial hydrolysis. The substance showed considerable anticomplementary activity.

A method to determine rapidly the identities and proportions of the oligosaccharide repeating-units in plant cell-wall xyloglucans by 1D 1H-n.m.r. spectroscopy was developed. Six of the most commonly found xyloglucan oligosaccharide subunits (including three subunits that had not been fully characterized previously) were prepared by endo-(1----4)-beta-D-glucanase digestion of xyloglucans from various plant species. The oligosaccharides were reduced to the corresponding oligoglycosyl-alditols, purified, and characterized by glycosyl composition and linkage analysis, 1H-n.m.r. spectroscopy, and f.a.b.-mass spectrometry. Correlations between the 1H-n.m.r. spectra and the structures of the oligoglycosyl-alditols can be used to identify oligoglycosyl-alditols derived from xyloglucans of unknown structure. The identities and relative amounts of the oligosaccharide subunits of xyloglucans isolated from tamarind seed and rapeseed hulls were determined on this basis.

The Watford and South Mimms sections of the London Orbital (M25) Motorway opened in late 1986. The rate of lead contamination in vegetation, surface soil, dust and airborne fractions since those dates is presented. Lead values were determined by inductively coupled plasma-source mass spectrometry (ICP-MS) with inter-analytical method comparison using flameless atomic absorption spectroscopy (NFAAS). A consistently high level of correlation (r = +0.91) was obtained for analysis of digested reference materials and (r = +0.84) for digested environmental sample solutions using these two methods. Quality control assessment was made using seven international reference materials covering the range of matrices under investigation. Analytical precision values (n = 20 replicates) for ICP-MS measured Pb levels in soil and vegetative reference materials are 6.1 to 11.1% and 3.3 to 7.1%, respectively. Overall accuracy of the analytical procedures used in this study is very good with a high degree of agreement between measured ICP-MS values and those either certified or reported in the literature. A rapid rate of Pb deposition occurs within the first months following the opening of the motorway in relation to emissions from approximately 90,000 vehicles day-1 (Watford) and approximately 75,000 vehicles day-1 (South Mimms). At 12 months elevated Pb levels extend to distances of greater than 100 m from the motorway.(ABSTRACT TRUNCATED AT 250 WORDS)

The use of lead in petrol in Israel is described. Results of a soil survey are presented and the distribution of lead in soil, water, air, edible plants and the human organism is reviewed. Soils do not generally show high lead retention. The concentrations of lead in water, air and edible plants are low as is the concentration of lead in blood. A possible source of danger is the use of spent motor oil as a fuel in glass making furnaces.

The aerial parts of Baccharis pingraea, collected in Chile, afforded, in addition to two diterpene glycosides isolated previously, 14 new ones and two of the corresponding desacyl aglycones. The structures were elucidated by high field 1H NMR spectroscopy. The differences between the collections from Argentina and Chile are discussed.

Two new flavonol glycosides from the seeds of Chenopodium quinoa have been isolated. Their structures were established as kaempferol 3-apiofuranosyl(1"'----2")rhamnopyranosyl(1""----6")galactoside and kaempferol 3-apiofuranosyl(1"'----2")rhamnopyranosyl(1""----6")galactoside. The main flavonoid glycoside was kaempferol 3-(2,6-dirhamnopyranosyl)galactoside.

The glycoside of a new class of phytosteroids has been isolated from Solanum carolinense. The steroidal aglycone (carolinone) is alkylated at C-3 and is identified as C-[(2,4,5-trideoxy-3-keto-4,5-dehydro)-pentulopyranosyl]-(5----3)- (13,14- seco-14 beta,17 alpha-dihydroxy) estrogen. The hydrolytic labile glycosyl moiety is identified as O-(beta-D-glucopyranosyl) (1----1)-[L-(2,6-dideoxy-3-C-methyl)- arabinopyranose]. The linkage of this disaccharide in the steroidal glycoside (carolinoside) is shown to be O-(alpha-pentulopyranosyl)- (1----4)-O-(beta-L-arabinopyranosyl)-(1----1)-D-glucopyranose. Carolinoside occurs at concentrations of 10(-7)-10(-6) M in leaf tissue and was shown to be the host plant specific feeding induction factor for Manduca sexta.

Leaves of Hosta ventricosa yielded eight kaempferol glycosides, of which six: the 3-(2G-glucosylrutinoside)-7-glucoside, 3-sophoroside-7-glucoside, 3-rutinoside-7-glucoside, 3-(2G-glucosylrutinoside), 3-sophoroside, 3-rutinoside were fully characterized and two: the 3-xylosylrutinoside-7-glucoside and 3-xylosylrutinoside were tentatively identified. Investigations included 1H-1H COSY and 1H-1H 2D J NMR analysis.

The ether-soluble resin glycoside ('jalapin') fraction obtained from scammony roots, on alkaline hydrolysis, gave a glycosidic acid, scammonic acid A, together with isobutyric, 2S-methylbutyric and tiglic acids. In addition, two kinds of resin glycosides, named scammonin I and II, were isolated and characterized, respectively, as (11S)-hydroxyhexadecanoic acid, 11-[( O-6-deoxy-4-O-(2(E)-methyl-1-oxo-2- butenyl)-beta-D-glucopyranosyl-(1----4)-O-6-deoxy-2-O-(2-methyl-1-oxobut yl)- alpha-L-mannopyranosyl-(1----2)-O-beta-D-glucopyranosyl-(1----2)-6-deoxy -beta- D-glucopyranosyl]oxy)-, intramol. 1,3"'-ester and (11S)-hydroxyhexadecanoic acid, 11-[( O-beta-D-glucopyranosyl-(1----4)-O-6-deoxy-2-O-(2-methyl-1-oxobutyl)- alpha-L-mannopyranosyl-(1----2)-O-beta-D-glucopyranosyl-(1----2)-6-deoxy -beta-D - glucopyranosyl]oxy)-, intramol. 1,3"'-ester.

Clematoside-S, a new triterpenoid saponin from the roots of Clematis grata, has been identified by chemical and spectroscopic methods as hederagenin-3-O-beta-D-ribopyranosyl (1----3)-alpha-L-rhamnopyranosyl(1----2)-alpha-L-arabinopyranoside .

Two new flavonol glycosides were isolated from the roots and rhizomes of Vancouveria hexandra. The glycosides were determined by chemical and spectral means to be anhydroicaritin 3-galactosyl(1----3) rhamnoside-7-glucoside and anhydroicaritin 3-[6-O-acetyl-galactosyl(1----3)rhamnoside]-7-glucoside.

Eight flavone glycosides were isolated from fronds of Asplenium normale, its two varieties, var. boreale and var. shimurae, and related species, A. oligophlebium. Six of the glycosides were identified: apigenin 7-O-dirhamnoside and 7-O-glucosylrhamnoside, luteolin 7-O-dirhamnoside and 7-O-glucosylrhamnoside, genkwanin 4'-O-glucosylrhamnoside, and vicenin-2. The remaining two glycosides were tentatively characterized as genkwanin 4'-O-glycoside and 6,8-di-C-glycosylluteolin. The four taxa analysed in this survey all had distinctive flavonoid profiles.

A novel feruloylated xyloglucan disaccharide and p-coumaroylated arabinoxylan trisaccharide were isolated from cell walls of growing bamboo (Phyllostachys edulis) shoots. On the basis of chemical and spectral data, their structures were determined to be O-(4-O-trans-feruloyl-alpha-D- xylopyranosyl)-(1----6)-D-glucopyranose and O-[5-O-(trans-p-coumaroyl)- alpha-L-arabinofuranosyl]-(1----3)-O-beta-D-xylopyranosyl-(1----4)-D- xylopyranose, respectively. This is the first reported evidence of a phenolic acid covalently associated with the cell wall hemicellulose, xyloglucan.

From a methanolic extract of leaves of Alangium platanifolium var. trilobum, benzyl alcohol xylopyranosyl(1---6)glucopyranoside, phenethyl alcohol xylopyranosyl(1----6)glucopyranoside and Z-hex-3-en-1-ol (aoba alcohol) xylopyranosyl(1----6)glucopyranoside were isolated. Their structures were determined mainly by NMR spectroscopy.

Only three gum exudates are permitted for pharmaceutical and food use by international regulatory authorities, viz. gum tragacanth (Asiatic Astragalus spp.), gum karaya (Sterculia spp.) and gum arabic [Acacia senegal (L.) Willd.], but a wide range of other tree exudates is used for a variety of uses in their countries of origin. This paper presents analytical data for the gum exudates from Atalaya hemiglauca, Cassine aethiopica, Combretum paniculatum, Sclerocarya birrea, and Pseudocedrela kotschyi. These gums may have local technological applications, but are not recommended for addition to foodstuffs.