Band 56, Heft 11-12

The process of brain aging is an interaction of age-related losses and compensatory mechanisms. This review is focused on the changes of the synaptic number and structure, their functional implications, regarding neurotransmission, as well as the electrical activity of neuronal circuits. Moreover, the importance of calcium homeostasis is strongly emphasized. It is also suggested that many neuronal properties are preserved, as a result of adaptive mechanisms, and that a series of interdependent factors regulate brain aging. The "new fron­ tier" in research is the challenge of understanding the effects of aging, both to prevent degen­ erative diseases and reduce their consequences. New aspects are considered a) the role of nitric oxide, b) free radicals and apoptosis, c) impaired cerebral microcirculation, d) m eta­ bolic features of aging brain, e) the possible neuroprotective role of insulin-like growth factor-1 (IGF-1) and ovarian steroids and e) stress and aging. These numerous multifactorial approaches are essential to understand the process of aging. The more we learn about it, the more we realize how to achieve "successful" aging. M inireview

Essential oil from herb and rhizome of Peucedanum ostruthium (L.Koch.) ex DC un­ derwent qualitative and quantitative analyses. The content of the oil obtained by hydrodistil­lation was 0.95% in the herb and 1.25% in the rhizome (per dry weight basis). Gas chroma­ tography (GC) with MS detection and flame ionisation detection showed that the oil from the rhizome contains 39 compounds, of which 29 were identified. Gas chromatography with flame ionisation detection in chiral columns against standard compounds showed the pres­ence of enantiomers of some of the components of the oil. Compounds present in largest quantities are: sabinene (35.2%) of which (+) sabinene accounts for (96.54%) and 4-terpineol (26.6%) of which (+) 4-terpineol accounts for (65.8%). 44 com ponents were found in the herb essential oil, of which 39 compounds were identified. Compounds present in largest quantities were β-caryophyllene (16.1%) and a-hum ulene (15.8%). The content of sabinene in the herb oil was 4.7%. The following compounds were present in the herb oil only as enantiomers: (+) sabinene (4.7%), (-) limonene (4.4%), (-) β-pinene (0.4%). A coumarin (osthole) was detected in both essential oils (5.5% in herb oil and 5.1% in rhizome oil).

From a Pseudom onas aeruginosa hospital isolate a new pyoverdin was isolated. It is iden­tical with that of Pseudomonas aeruginosa strain R except that in the peptide chain L-Gln is missing.

This paper describes the isolation of four phytoconstituents from the leaves of Bauhinia microstachya, a Brazilian medicinal plant used in folk medicine for the treatment of several ailments. Based on spectroscopic evidence, these compounds were identified as methyl gal-late (1), kaempferol 3-O-rhamnosyl (2), quercitrin (3) and myricitrin (4). The crude metha-nolic extract and two compounds (3 and 4) were tested as analgesic using the writhing test in mice. The extract and compound 3 caused potent and dose-related analgesic effects, con­ firming the popular use of this plant for the treatment dolorous processes.

Six natural polyphenolic compounds, brevifolin carboxylic acid, brevifolin, ellagic acid, methyl gallate, gallic acid and protocatechuic acid have been isolated from the methanol extract of the whole plant of Erodium cicutarium (L.) L.’Herit. (Geraniaceae). Structures were determined by conventional methods of analysis and confirmed by MS and NMR spectral analysis. The distribution of these compounds in the other species of the Erodium genera (E. botrys, E. chium, E. ciconium, E. cicutarium, E. glutinosum subsp. dunense, E. gruinum, E. manescavi, E. pelargoniiflorum, E. petraeum ) were examined by HPLC with a RP-18 column, and MGD-TLC methods on unmodified silica gel and silica gel chemically modified with polar and nonpolar groups (HPTLC-Si 60 LiChrospher, HPTLC-NH 2 , HPTLC-DIOL, HPTLC RP-18W).

A phytochemical investigation of the New Zealand endemic Apiaceae species Anisotome lyallii Hook.f. yielded (+)-α-angeloyloxylatifolone (1), 6-0-angeloyl-8-0-tigloyl-6β,8α,11-trihydroxygermacra- 1(10)E,4E-diene (2), 6-O-tigloyl-8-O-tigloyl-6β,8α,11-trihydroxygermacral( 10)E,4E-diene (3) and 6-O-tigloyl-8-O-tigloyl-la,6β,8α,11-tetrahydroxygermacra-4E,10- (14)diene (4). The structures were elucidated by HR mass spectrometry and 1D- and 2DNMR spectroscopy. A chemosystematic survey for compounds 1 - 3 in other New Zealand Apiaceae by HPLC-MS revealed that 1 - 3 were confined to A. haastii Cockayne & Laing and A. lyallii, and that some minor compounds in other species of Anisotome were isomers of 2 and 3.

The aerial parts of A. chrysocoma and A. coarctata afforded 22 and 9 sesquiterpene lactones, respectively. All the compounds described are new for the studied species. The lactones 5, 6 and 12 are new for the genus Achillea.

From the roots of Crepis conyzifolia, two new and two known guaianolides were isolated together with three known phenylpropanoids. Structures of the new compounds were estab­lished as 8β-hydroxy-4β, 15-dihydrozaluzanin C and 4β, 15, 11β, 13-tetrahydrozaluzanin C-3-O-β-glucopyranoside by spectral methods. The identity of 8 -epiisolippidiol and dentalactone was also discussed.

Three new iridoid glucosides, 10-O-[(E)-cinnamoyl]-geniposidic acid, 10-O-[(E)-p-coumaroyl]- geniposidic acid, 10-O-[(E)-caffeoyl]-geniposidic acid and the known iridoid glucoside, 2′-O-[(E)-cinnamoyl]-mussaenosidic acid have been isolated from Avicennia marina. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1 H - 1 H COSY, HMQC and HMBC experiments.

The aerial parts of Tephrosia carrollii afforded two chromene chalcones. Their structures and stereochemistry were established by spectroscopic methods. The structure of oaxacacin was revised and confirmed by X-ray diffraction. In this paper, we describe the isolation of the chalcone known as "oaxacacin" and the new chalcone named epoxyobovatachalcone. The compound der. oaxacacin was found to be identical with obovatachalcone based on spectroscopic evidence and X-ray diffraction.

Thirty-seven plant organs, traditionally used as drugs, collected in Pakistan, were extracted with 70% acetone and analyzed for their total phenolics concentration and antioxidant potential. Seven extracts showed more than 85% inhibition of lipid peroxidation in vitro as compared with blank. Butylated hydroxytoluene (BHT) (IC 50 = 233.6 μg / 1 ± 28.3) was the strongest antioxidant in our test system. The IC 50 results indicate that the extracts of Nymphaea lotus L. flowers, Acacia nilotica (Linn.) Delile beans, Terminalia belerica Roxb. fruits, and Terminalia chebula Retz. (fruits, brown) were stronger antioxidants than a-tocopherol, while Terminalia chebula Retz. (fruit coat), Terminalia chebula Retz. (fruits, black) and Ricinus communis L. leaves were weaker antioxidant extracts than a-tocopherol and BHT. Total phenolics concentration, expressed as gallic acid equivalents, showed close correlation with the antioxidant activity. High performance liquid chromatographic analysis with diode array detection at 280 nm, of the seven extracts indicated the presence of hydroxybenzoic acid derivatives, hydroxycinnamic acid derivatives, flavonol aglycones and their glycosides as main phenolics compounds. This information, based on quick screening methods, enables us to proceed towards more detailed chemical and pharmacological understanding of these plant materials.

Volatile constituents and a hexane extract of the leaves of Halimium voldii Kit Tan, Perde t­zoglou & Raus, sp. nova, were analyzed by GC and GC-MS. Thirty compounds were iden­tified in the essential oil of Halimium representing 88.7% of the oil composition. The main components were nonanal (12.8%), dodecane (10.6%), Z-caryophyllene (8.2%), y-muuro-lene (10.9%), δ -cadidene (3.5%), caryophyllene oxide (5.1%), β-eudesmol (3.6%) and ma-noyl oxide (5.5%). Thymol was identified in the hexane extract as the main compound. A labdane diterpene ent-labd-7, 13 (E)-dien, 15-ol was detected by its mass spectra fragmenta­tion pattern and its structure was determined by spectroscopic methods and its optical rota­tion. The essential oil and the hexane extract were assayed for their antimicrobial activity against Gram (+) and Gram (-) bacteria.

Two novel phenylacetoxylated p-terphenyl derivatives, namely ganbajunin F (6′-methoxy-2′-phenylacetoxy-3′, 4, 4″, 5′-tetrahydroxy-p-terphenyl), and ganbajunin G (5′-methoxy-2′-phenylacetoxy-3′, 4, 4″, 6′-tetrahydroxy-p-terphenyl), together with a known compound cycloleucomelone were isolated from the fruiting bodies of Thelephora ganbajun Zang. Their structures were established on the basis of spectral (MS, IR, NMR, HMBC, HMQC measure­ment) and chemical evidence.

A new ecdysteroid glycoside, lim nantheoside C (20-hydroxyecdysone 3-O-β-ᴅ-glucopyra-nosyl-[→3]-β-ᴅ-xylopyranoside [1]), together with limnantheoside A (20-hydroxyecdysone 3-O-β-ᴅ-xylopyranoside [2]) and 20-hydroxyecdysone (3) have been isolated by bioassay/RIA-directed HPLC analyses of a methanol extract of the seedmeal of Limnanthes alba Hartw. ex Benth. The structure of the novel ecdysteroid glycoside (1) was determined unambigu­ously by UV, LSIMS and a combination of ID -and 2D-NMR experiments. These three compounds are isolated from Limnanthes alba for the first time.

Influence of some new am inophosphonates on electrolyte leakage from cucumber (Cucu­-mis sativus cv "Wisconsin") cotyledons as well as on the content of chlorophyll and activity of guaiacol and pyrogallol peroxidase were studied. Concentration of malondialdehyde (MDA), one of the end-products of lipid peroxidation, was also measured. It was found that am inophosphates influenced the parameters observed to various extents, depending on their structural features and the concentration used. Most active modifiers were those possessing sufficiently long hydrocarbon substituents at the nitrogen atom and/ or iso-propyl chain at the phosphorus atom.

Hemolysis and fluidization of erythrocytes (RBC) membranes by some newly synthesized aminophosphonates as well as their potency to induce electrolyte efflux from cucumber (Cu­cumis sativus cv "Wisconsin") cotyledons were studied. Also, the chlorophyll content in aminophosphonate-treated cotyledons was affected. The compounds studied differed mainly in hydrophobicity of their substituents at the carbon, nitrogen and phosphorus atoms. It was found that aminophosphonate potency to fluidize RBC membranes depended on the combination of its overall lipophilicity and/or the kind of substituent at the P atom. Espe­cially, iso-propyl groups enhanced that potency. The sequence of am inophosphonates that exhibited the strongest fluidization activity was paralelled by their physiological and hem o­ lytic activities; in the latter case for these compounds that hemolyzed RBC under used con­ centrations. A general conclusion is that both the stereochemistry and lipophilicity determine the effi­ciency of the aminophosphonates studied. This efficiency is most probably related to the interaction of aminophosphonates with the lipid phase of biological objects.

2,3,5-trithiahexane, 2,3,4,6-tetrathiaheptane, 2,4,5,7-tetrathiaoctane, two pentathianonanes, 2,4,5,7,9-pentathiadecane and two hexathiaundecanes were isolated from the essential oil and extracts from the bark of Scorodophloeus zenkeri Harms. Four other thioalkanes were found in small amounts in the essential oil.

The two investigated algae had almost identical sterol composition, but there were signifi­cant differences in the com position of the polar components and especially in the composi­tion of the volatiles. P. denudata f. fragilis extracts possessed a stronger biological activity (antibacterial, antifungal and toxicity against Artemia salina). Despite the minute morpholog­ical differences between the two algae, we recommend P. denudata f. fragilis to be regarded as P. denudata subsp. fragilis.

The in vitro properties of semi-purified chlorophyllase (chlorophyll-chlorophyllido hy­drolase, EC 3.1.1.14) from Capsicum annuum fruits have been studied. The enzym e showed an optimum of activity at pH 8.5 and 50 °C. Substrate specificity was studied for chlorophyll (Chi) a, Chi b, pheophytin (Phe) a and Phe b, with K m values of 10.70, 4.04, 2.67 and 6.37 μᴍ respectively. Substrate inhibition was found for Phe b at concentrations higher than 5 μᴍ. Chlorophyllase action on Chi a' and Chi b' was also studied but no hydrolysis was observed, suggesting that the mechanism of action depends on the configuration at C-13 2 in the chloro­ phyll molecule, with the enzyme acting only on compounds with R13 2 stereochemistry. The effect of various metals (Mg 2+ , Hg 2+ , Cu 2+ , Zn 2+ , Co , Fe 2+ and Fe 3+ ) was also investigated, and a general inhibitory effect was found, this being more marked for Hg 2+ and Fe 2+ . Func­tional groups such as -SH and -S-S-seem ed to participate in the formation o f the enzyme-substrate complex. Chelating ion and the carbonyl group at C3 appeared to be important in substrate recognition by the enzyme. The method for measuring Chlase activity, including HPLC separation of substrate and product, has been optimized.

Enzyme production of newly isolated thermophilic inulin-degrading Bacillus sp. 11 strain was studied by batch cultivation in a fermentor. The achieved inulinase and invertase activi­ ties after a short growth time (4.25 h) were similar or higher compared to those reported for other mesophilic aerobic or anaerobic thermophilic bacterial producers and yeasts. The investigated enzyme belonged to the exo-type inulinases and splitted-off inulin, sucrose and raffinose. It could be used at temperatures above 65 °C and pH range 5.5-7.5. The obtained crude enzyme preparation possessed high thermostability. The residual inulinase and inver­ tase activities were 92-98% after pretreatment at 65 °C for 60 min in the presence of substrate inulin.

AM -toxins are host-specific phytotoxins of the Alternaria alternata apple pathotype, which induce necrosis on apple leaves. In this study, we developed a new assay to measure the necrotic activity of AM -toxin analogs using cultured leaves from meristem cells. This method was not only more sensitive to AM -toxin I, but also more reliable than the previous one that used tree leaves due to the homogeneous nature of cultured leaves and to the method of application of toxins. U sing this assay method we investigated a structure-activity relationship of AM -toxin analogs synthesized in this study. Most residues and the macrocyclic ring structure were strictly recognized by AM -toxin putative receptor, whereas the L-Ala binding subsite of the receptor allowed for side chain structures with various stereoelectronic properties. These findings are important for designing ligands for further experimental probing of the nature of the receptor.

Exogenous jasmonic acid (JA) and methyl jasmonate (MJ) induced accumulation of isofla­ vone constituents in cotyledons prepared from imbibed seeds of white lupin (Lupinus albus L.). Exogenous 0.2 mᴍ MJ enhanced the levels of 7-O-(6″-O-m alonyl)glucosylgenistein and 7-O -glucosylgenistein in the cotyledons of etiolated seedlings that had been incubated in the dark for 48 h. Regarding isoflavone induced by excision and slicing in the cotyledons as background level, the effect of light was 2-to 3-fold higher than that of 0.2 mᴍ MJ. C otyle­ dons exposed to MJ along with a 24-h light period displayed a higher level of isoflavone accumulation than that o f light alone. Total molar amounts of isoflavone accumulated in the cotyledons treated with MJ under continuous light were approximately the sum of those induced by MJ alone and light alone, respectively. The additive-like effect of MJ and light on isoflavone accumulation in lupin tissues suggested the presence of two different signaling systems independently responsible for those two stimuli. Excised cotyledons from etiolated yellow lupin (L. luteus L. cv. Topaz) seedlings also supported this hypothesis. The cotyledons could accumulate both an isoflavone and a flavone, and MJ selectively increased some of the isoflavone constituents, whereas light enhanced the levels of both. The selective accumulation mechanism of isoflavonoids in cotyledons, in which jasmonoids are involved, clearly differed from that activated by light.

The fatty acid compositions of plastidic and extra-plastidic membrane lipids of two metri-buzin-resistant cell lines L4 and L7 of C henopodium rubrum were determined after growth in the absence and in the presence of the herbicide and compared with those o f wild type cells. Fatty acid biosynthesis was markedly affected in all cell lines by metribuzin treatment. In the absence and in the presence of metribuzin alterations of the fatty acid com position of the various lipid classes were, as compared to wild type cells, generally lower in the highly resistant L4 cells than in the less resistant L7 cells. The two resistant cell lines demonstrated a higher degree of unsaturation within the plastidic monogalactosyldiacylglycerols (L4 cells also within plastidic digalactosyldiacylglycerols) and, particularly, within the predominantly extra-plastidic phosphatidylcholines (L7 cells also within the predominantly extra-plastidic phosphatidylethanolamines), whereas the degree of unsaturation was slightly altered in the plastidic phosphatidylglycerols. Within the two metribuzin-resistant cell lines, the highly resis­ tant L4 cells differed from the less resistant L7 cells by increased a-linolenic acid/palmitic acid ratios in both the plastidic and extra-plastidic membrane lipids suggesting that particu­ larly in L4 cells higher proportions of linolenate are formed as a result o f selection pressure. On the other hand, the proportion of linoleate was increased predominantly in extra-plastidic membrane lipids of both L4 and L7 cells which explains a raise in linoleic acid/palmitic acid ratios in both cell lines as compared to wild-type cells. Moreover, in the absence of metri­ buzin decreased proportions o f fram-3-hexadecenoic acid were found in phosphatidylglycer­ ols of L4 and, particularly, of L7 cells as compared to the wild type cells. It is suggested that L4 and L7 cells -having multiple mutations in the psbA gene as observed earlier -are additionally characterized by increased degree of unsaturation of acyl moieties in various polar lipids, e.g. linoleoyl moieties in L4 and L7 cells as well as linolenoyl moieties particularly in highly resistant L4 cells. This increase gives rise to a change in membrane fluidity and may finally lead to increased metribuzin resistance.

Distinct concentration ranges of selected quaternary ammonium and phosphonium salts were elaborated to induce stimulatory or inhibitory effects, respectively, on photosynthetic reactions. By means of fluorescence induction measurements 3 different effects of alkylbenzyldimethylammonium chloride (ABDAC; zephirol) in chloroplast preparations from Pisum sativum were observed. 60 μᴍ ABDAC produced a strong increase in F max with concurrently improved Kautsky kinetics. Increased ABDAC concentration (500 μᴍ) led to a strong fluorescence quenching - virtually indistinguishable from the conditions following the addition of photosystem II electron acceptors like K 3 Fe[CN] 6 . Further increase of ABDAC to 5 mᴍ provoked a drastic increase in the fluorescence yield together with the complete loss of any detectable kinetics. We suggest a 3-step interaction of ABDAC with the thylakoid membranes of photosynthetic organisms similar to our earlier discussion (Bader and Höper (1993), Z. Naturforsch. 49 c, 87 -94 ). We examined a series of derivatives with selectively modified side chains, central atoms and counter ions, respectively. Both an alkyl chain of the type ([-CH 2 -] n ; n ~ > 10) and effective polar components are indispensable for the adsorption and intercalation of the molecule onto and into the thylakoid membranes. The benzyl group could be replaced by a methyl residue without any loss of effectiveness; replacement of the central nitrogen (N) by phosphorus (P) and the counter ion Cl by Br did not modify the effects and the results were indistinguishable from the ABDAC effect proper. Shortening of the alkyl chain to (-CH 2 -) 6 resulted in a less effective interaction of e.g. tetraoctylammonium bromide with the photosynthetic membrane. Flash-induced oxygen evolution measurements with selected derivatives (15 μᴍ) substantiated our interpretation of an improved OEC functioning by a substantial lowering of the miss parameter a and the exclusion of a chemical reduction as the standard S-state distribution was not affected. As evidenced by both SDS-PAGE and Western blot analyses the investigated molecules showed a direct interaction. The polypeptide patterns were characterized by a severe shift of the molecular weight components from high (20 -67 kDa) to low (< 20 kDa) values.

RbcS antisense DNA mutants of tobacco have reduced amounts of ribulose bisphosphate carboxylase oxygenase (Rubisco). We found that carotenoid and chlorophyll contents decrease in parallel as Rubisco is decreased, however, pigment levels are not significantly altered until Rubisco levels are reduced sharply. The mutants have normal Chi a /Chi b ratios and normal plastid ultrastructures, suggesting that reductions in Rubisco do not dramatically alter the composition of the thylakoid membranes. Nevertheless, chlorophyll fluorescence measurements, in which developmentally homogenous leaves were sampled, showed that there is reduced photosynthetic capacity of PSII and an enhanced photosensitivity in the mutants, especially in transgenics with severe reductions in Rubisco content. Support for this conclusion comes from several observations; 1) light saturation occurs at a lower light inten­ sity in the mutants, resulting in an earlier closure of PS II (lower photochemical quenching); 2) the mutants have reduced photosynthetic efficiency (lower ΔF/Fm'); and 3) the mutants have a slower recovery of Fv/Fm. We found that acclimation to increasing light intensies in the mutants appears to involve an enhanced inactivation of PSII reaction centers as well as an increased activation of photoprotective mechanisms, notably an engagement of the xanthophyll cycle at lower than normal light intensities. We conclude that the photosensitivity of the antisense mutants is due, in part, to a limitation in Rubisco activation state.

In this paper we present proton spin-lattice ( T 1 ) and spin-spin ( T 2 ) relaxation times measured vs. concentration, temperature, pulse interval (τ CPMG ) as well as 1 H NMR spectral measurements in a wide range of concentrations of bovine serum albumin (B SA ) solutions. The anomalous relaxation behaviour of the water protons, similar to that observed in mammalian lenses, was found in the two most concentrated solutions (44% and 46% ). The functional dependence of the spin-spin relaxation time vs. τ CPMG pulse interval and the values of the motional activation parameters obtained from the temperature dependencies of spinlattice relaxation times suggest that the water molecule mobility is reduced in these systems. The slow exchange process on the T 2 time scale is proposed to explain the obtained data. The proton spectral measurements support the hypothesis of a slow exchange mechanism in the highest concentrated solutions. From the analysis of the shape of the proton spectra the mean exchange times between bound and bulk water proton groups (τ ex ) have been estimated for the range of the highest concentrations (30% - 46% ). The obtained values are of the order of milliseconds assuring that the slow exchange condition is fulfilled in the most concentrated samples.

The influence of single chain lipids on the 7-ethoxycoumarin O-deethyase activity of the reconstituted binary protein complex of isolated cytochrome P450 and NADPH-cytochrome P450 reductase has been examined. The enzyme activity of this binary enzyme complex has been shown to be influenced by (i) altering the complexation process of both proteins, (ii) by altering the catalytic cycle time of the active binary protein complex and (iii) by altering the fraction of substrate molecules at the catalytic center of the enzyme. Competitive inhibition was measured for all single chain molecules. The following dissociation coefficients of sub­ strate and lipids used for the catalytic center of the protein were obtained: 110 μм 7-ethoxy-coumarin (substrate), 1.1 μм MOG (1-monooleoyl-rac-glycerol), 0.3 μм SPH (D-sphingosine), 1.5 μм OA (oleic acid), 3.0 μм LPC (L-a-lysophosphatidyl-choline), 15.5 μм MSG (1-mono-stearoyl-rac-glycerol), 9.5 μм AA (arachidonic acid), 9.0 μм PaCar (palmitoyl-L-carnitine), 3.5 μм MPG (2-monopalmitoyl-glycerol), 1.5 μм LPI (L-a-lysophosphatidyl-inositol), 50 μм LA (lauric acid), 60 μм MA (myristic acid). 85 μм PA (palmitic acid), >100 μм SA (stearic acid). Only competitive inhibition with the substrate molecule 7-ethoxycoumarin was ob­served for the single chain lipids LA, MA, PA, SPH, SA, and OA. Non-competitive effects were observed for MPG (-0.03 μм -1 ) , PaCar (-0.02 μм -1 ) , MSG (-0.023 μм -1 ) , LPC (-0.03 μм -1 ) , A A (-0.03 μм -1 ) , and MOG (+0.04 μм -1 ). The negative sign indicates that the cycle time of the working binary complex is enlarged. The positive sign indicates that the formation of the binary complex is enhanced by MOG.

A phytochemical study of two plant species, Viscum cruciatum Sieber and Crataegus mono­gyna Jacq., was completed to investigate the influence of the parasite Viscum cruciatum on the host Crataegus monogyna. The study was carried out with two samples and consisted of hexane extracts of the Viscum cruciatum parasitizing on Crataegus monogyna and C. mono­gyna. In these samples ursolic acid, β-sitosterol and a triterpene fraction were found that contained mainly butyrospermol (3β-lanost 8 , 24-dien, 3-ol), 24-methylene-24-dihydrolanost-erol (24-methylene-5a-lanost-8-en-3β-ol), cycloartenol (9β, 19-cyclo-5α, 9β-lanost-24-en-3β-ol), β-amyrin (olean-12-en-3β-ol) and several aliphatic alcohols identified as the C 18 to C 30 members of the 1 -alkanol homologous series. β-Amyrin acetate was only isolated from Viscum cruciatum and was not found in Cratae­ gus monogyna.

A pathogenesis-related protein induced by infection with Ascochyta rabiei was purified from intercellular washing fluid of chickpea (Cicer arietinum L.) leaves. Amino-terminal se­quencing identified the protein, named PR-5a, as a thaumatin-like protein. The isoelectric point was determined with 6.5 and the molecular mass is 16 kDa. Therefore, chickpea PR-5a is the first dicot member of a TLP subgroup containing small TLPs with a molecular weight between 15 and 18 kDa. PR-5a shows no antifungal activity towards A. rabiei. Screen­ ing of a chickpea cDNA library led to the isolation of a cDNA clone (p5a-241) for this protein. A second cDNA clone (ELR112) encoding a TLP was isolated using differential hybridisation of cDNA libraries obtained from elicited and water treated cell suspension cultures of chickpea. The deduced protein (PR-5b) has a molecular mass of 22 kDa. PR-5b is postulated to be located in the vacuole due to the presence of a respective N-terminal signal peptide and a carboxy-terminal extension. Southern blot analyses showed that ELR112 and p5a-241 represent single copy genes. During fungal infection of chickpea plants expres­ sion of both genes proceeds much faster in an A. rabiei resistant cultivar than in a suscep­tible one.

Two diterpene glycosides, ent8(17)-labden-15-O-α-ʟ-rhamnoside and ent-8(17)-labden-15-O-(3′-O-acetyl)-α-ʟ-rhamnoside (new natural compounds) were isolated from propolis from El Salvador. The compounds showed significant antibacterial activity and moderate toxicity to Artemia salina nauplii. These are the first glycosides reported in bee glue.

The antibacterial activities of propolis samples have been examined in vitro, according to the principles accepted for the determination of a similar activity of antibiotics with the use of solid and liquid media. It has been found that propolis extracts showed antibacterial activity through a range of commonly encountered gram positive cocci (5. aureus, beta hem. Streptococus), but had weak activity against gram negative bacteria (E . coli, P. aeruginosa). GC/MS analysis showed that propolis samples contain a variety of chemical compounds in­ cluding aromatic compounds, fatty acid esters and sesquiterpenes.

A collection of the marine sponge Suberea aff. praetensa from the Gulf of Thailand fur­nished the bromotyrosine derivatives fistularin-3, agelorins A and B and the new desoxyagel-orins A and B.

Sex attractants for 3 Sesiidae and 3 Tineidae moth species in West-Kazakhstan and Lithua­nia were discovered by field screening tests of (3Z,13Z)-, (3E,13Z)-and (2E,13Z)-octadeca-dien-1-ols and their acetates as well as of some binary mixtures of these compounds. Total amount of chemicals was 0.3 mg/dispenser. Males of Synanthedon serica were attracted by a 5:5 mixture of 3E,13Z-18:OA c and 2E,13Z-18:OAc, Chamaesphecia bibioniformis by a 9:1 mixture of 3Z,13Z-18:OAc and 3E,13Z-18:OAc, Paranthrene tabaniformis by a 1:9 mixture of 3Z,13Z-18:OH and 3E,13Z-18:OH , Tinea nonimella by a 1:9 mixture of 3E,13Z-18:OH and 2E,13Z-18:OH , Monopis monachella by a 1:9 mixture of 3Z,13Z-18:OH and 2E,13Z -18:OH, and Nemaxera betulinella by a 9:1 mixture of 2E,13Z-18:OAc and the corresponding alcohol. The periods of attraction to the traps were registered for males of S. serica and Ch. bibioniformis and were found to occur at 15 - 18 and 1 5 -17 o'clock, local time, respectively.

Adults, particularly males, of a papilionid butterfly, Papilio machaon hippocrates, emit a fairly strong scent perceivable by humans. We have identified a variety of volatile compounds (hydrocarbons, alcohols, aldehydes, ketones, esters, and so on) from the wings and bodies of both sexes of the butterfly. Male wings secreted n-dodecane, linalool and geranylacetone as major components together with small amounts of camphene, limonene, p-cymene, 2 -phenylethanol, n-hexanal, n-decanal, isoamyl acetate, p-allylanisole, 2 -pyrrolidone and other characteristic volatiles. The overall profile of volatile compounds detected from male body was quite different from that of the wings. Male body was devoid of camphene, 2-phenyletha-nol, n-hexanal but instead contained limonene, acetoin, a sesquiterpene hydrocarbon (C 15 H 24 ), methyl n-octanoate, (E,E)-hepta-2,4-dienal, and another isomer of heptadienal as principal components, of which the last four compounds were specific to the body. All these substances seem to concurrently characterize the male odor. The chemical patterns of com­ pounds found from female wings and body were essentially the same in quality as those of male wings and body, respectively, although their quantities in females were generally smaller than in males. Females, however, had a larger amount of acetamide than males. The chemical compositions of volatiles from the fore and hind wings of males were not greatly different from each other, and every component was considered to be present on all parts of the wings. This suggests that the scent-producing organs or scent-emitting pores are widely distributed on the whole wings. EA G responses of both sexes to 12 selected compounds identified from the butterfly were not strong at a dose of 1 μg, while both sexes showed relatively stronger responses to n-nonanal, methyl n-octanoate, D-limonene and linalool at a higher dose (10 [μg). Although sexual difference in EAG response was not prominent, females appeared a little more sensitive, and n-nonanal and acetoin evoked significantly higher responses from females at 1 μg.

It has been previously shown that the sequence similarity between a portion of the enve­lope glycoprotein 120 (gp120) from the human immunodeficiency virus type-1 (HIV-1) and several types of human collagen and collagen-like molecules exists. That observation led to the suggestion that the antibodies against the third hypervariable region (V3) of HIV-1 gpl20 (V3-specific antibodies) might have a role in the autoimmune phenomena observed in HIV-infected persons. In this study we have examined the cross-reactivity of the V3-specific anti­ bodies purified from sera of HIV-infected individuals, sera obtained from the rheumatoid arthritis and systemic lupus erythematosus patients, as well as from the sera of healthy volun­ teers with the separate chains of a subcomponent of the first component of the human com­ plement system, C1q. Our results show that the V3-specific antibodies are present in the sera of the HIV-infected individuals, patients suffering of the systemic autoimmune diseases as well as in the sera of healthy volunteers. Whereas these antibodies appeared in the HIV+-sera after antigen challenge, those present in the H IV --sera probably represent the antibod­ ies that are cross-reactive with the antigen. V3-reactive antibodies can be purified by affinity chromatography and they were highly specific for the V3-peptide. Additionally, they showed cross-reactivity with the separate chains of the human C1q as well as with the chicken colla­ gen type VI. Possible physiological implications are discussed.

Capillary electrophoresis and ESI-Mass spectrometry methods have revealed that a hydro-peroxo-copper(II) complex with (tpa) (=tris(2-pyridylmethyl)amine) reacts with carbonic an-hydrase or amyloid beta-peptide (1 -40) as a nucleophile to induce the conformational change of the protein structure, while the Cu(bdpg)-complex ((bdpg)=N,N-bis(2-pyridyl-methy)-beta-alanineamide) acts as an electrophile toward the proteins to degrade them under the same experimental conditions. This will lead to suggest that enhanced nucleophilic attack by a copper(II)-peroxide adduct to peptide bonding may be one of the serious origins for the "gain-of-function" by mutant superoxide dismutase and for conformational change of normal prion protein.

The aim of this study was to investigate the effects of exogenously added pancreatic phos-pholipase A 2 (pPLA 2 ) on the production of reactive oxygen species by human polymorpho­ nuclear leukocytes (PMNs). Pancreatic PLA 2 was used because PMNs do not possess a re­ ceptor for that enzyme and, therefore, the receptor-mediated effects could be excluded. Respiratory burst activity of PMNs was monitored by luminol-amplified chemiluminescence and the lipid composition of neutrophils after treatment with pPLA 2 was determined by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Our results show that the products of the pPLA 2 digestion of the PMN membrane -lysophospholipids and the corresponding free fatty acids -significantly enhanced the respiratory burst response of human neutrophils.

We have examined the structure-activity relationships in methemoglobin (MetHb) forma­tion by high explosives 2,4,6-trinitrotoluene (TNT), 2,4,6-trinitrophenyl-N-nitramine (tetryl) and 2,4,6-trinitrophenyl-N-nitraminoethylnitrate (pentryl), and a number of model nitroben-zenes. In lysed human erythrocytes the rate constants of oxyhemoglobin (OxyHb) oxidation increased with an increase in single-electron reduction potential (E 1 7 ) or with a decrease of the enthalpies of single-electron reduction of nitroaromatics. Tetryl and pentryl oxidized Ox­yHb almost 3 times faster than TNT. Although the initial rates of MetHb formation in intact erythrocytes by tetryl, pentryl, and TNT matched their order of reactivity in the oxidation of OxyHb in lysed erythrocytes, TNT was a more efficient MetHb forming agent than tetryl and pentryl during a 24-h incubation. The decreased efficiency of tetryl and pentryl was attributed to their reaction with intraerythrocyte reduced glutathione (GSH) producing 2,4,6-trinitrophenyl-Sglutathione, which acted as a less efficient OxyHb oxidizing agent.

For the first time callus and suspension cultures of Li­num mucronatum ssp. armenum were initiated, grown in darkness at 25 °C and analyzed for lignans. 6-Methoxy-podophyllotoxin was the main lignan besides smaller amounts of podophyllotoxin isolated and identified by chromatographic methods as well as by 1 H NMR.

Glyceraldehyde-3-phosphate Dehydrogenase, ATP, Flu­ orescence Glyceraldehyde-3-phosphate dehydrogenase is a gly­colytic enzyme that catalyses conversion of glyceralde-hyde-3-phosphate to 1,3-diphosphoglycerate. ATP has been found to have an inhibitory effect on this enzyme. To establish the interaction between the enzyme and ATP, a fluorescence technique was used. Fluorescence quenching in the presence of ATP suggests cooperative binding of ATP to the enzyme (the Hill obtained coeffi­cient equals 2.78). The interaction between glyceralde-hyde-3-phosphate dehydrogenase and ATP may control not only glycolysis but other activities of this enzyme, such as binding to the cytoskeleton.

The expression of the ischemia-responsive protein (irp94) was enhanced by endoplasmic reticulum (ER) stress inducing drugs such as brefeldin A (BFA), calcium ionophor A23187, dithiothreitol (DTT) and tunicamycin in fisher rat thyroid epithelial cell line (FRTL-5 cells). In particular, irp94 mRNA expression was increased dose dependently by tunicamycin, and there was increased irp94 expression when the cells were incubated with the thyroid-stimulating hormone (TSH) together.