Volatiles from rhizomes of Rhodiola rosea L

Terpenes and aroma volatiles from rhizomes of Rhodiola rosea L. from Norway have been isolated by both steam distillation and headspace solid-phase micro-extraction coupled with gas chromatography and mass spectrometry analysis. The dried rhizomes contained 0.05% essential oil with the main chemical classes: monoterpene hydrocarbons (25.40%), monoterpene alcohols (23.61%) and straight chain aliphatic alcohols (37.54%). n-Decanol (30.38%), geraniol (12.49%) and 1,4-p-menthadien-7-ol (5.10%) were the most abundant volatiles detected in the essential oil, and a total of 86 compounds were identified in both the SD and HS-SPME samples. Geraniol was identified as the most important rose-like odour compound besides geranyl formate, geranyl acetate, benzyl alcohol and phenylethyl alcohol. Floral notes such as linalool and its oxides, nonanal, decanal, nerol and cinnamyl alcohol highlight the flowery scent of rose root rhizomes.     

Comparative phytochemical analysis of four Mexican Nymphaea species

Four Mexican Nymphaea species, N. ampla, N. pulchella, N. gracilis and N. elegans belonging to subgenera Brachyceras were analyzed. In this work two 5-glycosyl isoflavones, 7,3',4'-trihydroxy-5-O-beta-D-(2'-acetyl)-xylopyranosylisoflavone (1) and 7,3',4'-trihydroxy-5-O-alpha-L-rhamnopyranosylisoflavone (2), were isolated from N. ampla and N. pulchella, respectively, together with other known 3-glycosyl flavones and triterpene saponins from the same four species. The structures were elucidated by 1D and 2D NMR, FABMS, and other spectroscopic analyses. These results confirmed that the four species were different from each other and established that N. pulchella represents a different taxa than N. ampla. In addition, the 5-glycosyl isoflavones could be considered as a taxonomic character of this group of plants.     

Diversification of an ancient theme: hydroxynitrile glucosides

Many plants produce cyanogenic glucosides as part of their chemical defense. They are alpha-hydroxynitrile glucosides, which release toxic hydrogen cyanide (HCN) upon cleavage by endogenous plant beta-glucosidases. In addition to cyanogenic glucosides, several plant species produce beta- and gamma-hydroxynitrile glucosides. These do not release HCN upon hydrolysis by beta-glucosidases and little is known about their biosynthesis and biological significance. We have isolated three beta-hydroxynitrile glucosides, namely (2Z)-2-(beta-D-glucopyranosyloxy)but-2-enenitrile and (2R,3R)- and (2R,3S)-2-methyl-3-(beta-D-glucopyranosyloxy)butanenitrile, from leaves of Ribesuva-crispa. These compounds have not been identified previously. We show that in several species of the genera Ribes, Rhodiola and Lotus, these beta-hydroxynitrile glucosides co-occur with the L-isoleucine-derived hydroxynitrile glucosides, lotaustralin (alpha-hydroxynitrile glucoside), rhodiocyanosides A (gamma-hydroxynitrile glucoside) and D (beta-hydroxynitrile glucoside) and in some cases with sarmentosin (a hydroxylated rhodiocyanoside A). Radiolabelling experiments demonstrated that the hydroxynitrile glucosides in R. uva-crispa and Hordeum vulgare are derived from L-isoleucine and L-leucine, respectively. Metabolite profiling of the natural variation in the content of cyanogenic glucosides and beta- and gamma-hydroxynitrile glucosides in wild accessions of Lotus japonicus in combination with genetic crosses and analyses of the metabolite profile of the F2 population provided evidence that a single recessive genetic trait is most likely responsible for the presence or absence of beta- and gamma-hydroxynitrile glucosides in L. japonicus. Our findings strongly support the notion that the beta- and gamma-hydroxynitrile glucosides are produced by diversification of the cyanogenic glucoside biosynthetic pathway at the level of the nitrile intermediate.     

Enhanced Biotransformation Capacity of <Emphasis Type="Italic">Rhodiola rosea</Emphasis> Callus Cultures for Glycosid Production

Rhodiola rosea is a promising medicinal plant that produces various glycosides. Recently we developed a successful method for cultivating it in liquid cultures of compact callus aggregates. In a previous study we reported the successful production of the glycosides of R. rosea by biotransformation of cinnamyl alcohol and tyrosol. In the present study we investigated the possibility of further increasing the yields of the biotransformation products by addition of glucose to the culture medium aside from sucrose, which was used earlier as carbon source. Surprisingly, glucose addition doubled the yield of cinnamyl alcohol glycosides. Rosavin was not produced at all when only sucrose was used. When glucose was added the accumulation dynamics of rosin and a recently described derivative glycoside (designed as compound 321) were similar. Both increased during the first days and then remained constant, while other glycoside compounds increased continuously throughout the cultivation. Rosavin reached its maximum concentration after nine days. In contrast to the beneficial effect on cinnamyl alcohol related glycosides the addition of glucose did not affect the accumulation of the tyrosol derivative salidroside.     

Chemical markers in Veronica sect. Hebe. III

In a continued chemosystematic investigation of the water-soluble compounds in Veronica sect. Hebe, we have investigated two more of the species formerly classified as Parahebe. Both species contained mannitol in considerable amounts and in addition some glucosides of iridoid acids. Veronica cheesemanii was characterised by aucubin and its esters: 2′-O-benzoylaucubin and an aucubin diester named cheesemanioside. The main iridoid compounds in Veronica hookeriana were catalpol and its ester verminoside, but this species also contained the sugar ester methyl 1-O-benzoyl-3-α-glucuronosylglycerol and a caffeoyl phenylethanoid glycoside (CPG) named parahebeoside, a 2′-O-β-xylopyranosyl derivative of the known plantamajoside. The results show that the studied species of the former genus Parahebe are very different with regard to their chemical content. This is in agreement with the DNA sequence data and implies the genus was polyphyletic as previously circumscribed.     

Chemical markers in Veronica sect. Hebe. II

In a continued chemosystematic investigation of the water-soluble compounds in Veronica sect. Hebe, four additional species were investigated. In comparison to other, Northern Hemisphere (NH) species of Veronica, those belonging to the New Zealand species in sect. Hebe are apparently more variable in chemical content. In addition to the compounds characteristic for NH Veronica, namely mannitol, aucubin, catalpol and 6-O-esters of catalpol as well as some caffeoyl phenylethanoid glucosides (CGPs), Veronica topiaria (syn. Hebe topiaria) also gave an unusual 6-O-ester of aucubin named topiarioside. The former Hebe species Veronica cupressoides and Veronica stenophylla each provided one of the two previously undescribed disaccharide esters named hebitol I and II, respectively, and the former plant also provided a CPG named cuproside, a 6-O-β-glucopyranosyl derivative of the known hebeoside. The last species, namely Veronica hulkeana (syn. Heliohebe hulkeana) only contained compounds common to other species of Veronica. The taxonomic results are discussed and it is concluded that carbohydrate esters are common in sect. Hebe. The data so far obtained indicate that the occurrences of esters of 6-O-rhamnopyranosylcatalpol are confined to the most derived species in the section.     

Iridoid glycosides from the stems of Pithecoctenium crucigerum (Bignoniaceae)

Sixteen crude extracts from six Panamanian plants of the family Bignoniaceae were submitted to rapid TLC tests against DPPH and acetylcholinesterase. Pithecoctenium crucigerum (L.) A.H. Gentry, which showed interesting activity against DPPH, has been studied. The chemical investigation of the methanol extract from the stems afforded the iridoid glycoside theviridoside and three derivatives (6'-O-cyclopropanoyltheviridoside, 10-O-hydroxybenzoyltheviridoside and 10-O-vanilloyltheviridoside), along with five known phenylethanoid glycosides (verbascoside, isoverbascoside, forsythoside B, jionoside D and leucosceptoside B). These last compounds were all active against DPPH. The structures were determined by means of spectrometric and chemical methods, including 1D and 2D NMR experiments and MS analysis.     

Phenylethanoids, iridoids and a spirostanol saponin from Veronica turrilliana

From the aerial parts of Veronica turrilliana two phenylethanoid glycosides, turrilliosides A and B and a steroidal saponin, turrillianoside were isolated and their structures elucidated as beta-(3,4-dihydroxyphenyl)ethyl-4-O-E-caffeoyl-O-[beta-glucopyranosyl-(1-->4)-alpha-rhamnopyranosyl-(1-->6)]-beta-glucopyranoside, beta-(3,4-dihydroxyphenyl)ethyl-4-O-E-caffeoyl-[6-O-E-feruloyl-beta-glucopyranosyl-(1-->4)-alpha-rhamnopyranosyl-(1-->6)]-beta-glucopyranoside and (23S,25S)-12beta,23-dihydroxyspirost-5-en-3beta-yl O-alpha-rhamnopyranosyl-(1-->4)-beta-glucopyranoside, respectively. Furthermore, eight known glucosides are reported namely, catalpol, catalposide, verproside, amphicoside, isovanilloylcatalpol, aucubin, arbutin, and 6-O-E-caffeoylarbutin, the latter two for the first time in the genus Veronica. The two phenylethanoid glycosides were found to be potent DPPH radical scavengers. All of the tested compounds were inactive against the representative species of fungi and bacteria.     

Comparative studies of the polysaccharides from species of the genus Ramalina-lichenized fungi-of three distinct habitats

Several structurally different glucans (alpha- and beta-) and galactomannans were characterized as components of four species of the genus Ramalina, namely R. dendriscoides, R. fraxinea, R. gracilis and R. peruviana. Freeze-thawing treatment of hot aqueous extracts furnished as precipitates (PW) linear alpha-D-glucans of the nigeran type, with regularly distributed (1-->3)- and (1-->4)-linkages in a 1:1 ratio. The supernatants (SW) contained alpha-D-glucans with (1-->3)- and (1-->4)-linkages in a molar ratio of 3:1. The lichen residues were then extracted with 2% aq. KOH, and the resulting extracts submitted to the freeze-thawing treatment, giving rise to precipitates (PK2) of a mixture of alpha-glucan (nigeran) and beta-glucan, which were suspended in aqueous 0.5% NaOH at 50 degrees C, dissolving preferentially the beta-glucan. These were linear with (1-->3)-linkages (laminaran). The mother liquor of the KOH extractions (2% and 10% aq. KOH) was treated with Fehling's solution to give precipitates (galactomannans). The galactomannans are related, having (1-->6)-linked alpha-D-mannopyranosyl main chains, substituted at O-4 and in a small proportion at O-2,4 by beta-D-galactopyranosyl units. Despite the different habitats of these lichenized fungi, all species studied in this investigation have a similar pool of polysaccharides.     

The golden root, Rhodiola rosea, prolongs lifespan but decreases oxidative stress resistance in yeast Saccharomyces cerevisiae

The effect of aqueous extract from R. rosea root on lifespan and the activity of antioxidant enzymes in budding yeast Saccharomyces cerevisiae have been studied. The supplementation of the growth medium with R. rosea extract decreased survival of exponentially growing S. cerevisiae cells under H₂O₂-induced oxidative stress, but increased viability and reproduction success of yeast cells in stationary phase. The extract did not significantly affect catalase activity and decreased SOD activity in chronologically aged yeast population. These results suggest that R. rosea acts as a stressor for S. cerevisiae cells, what sensitizes yeast cells to oxidative stress at exponential phase, but induces adaptation in stationary phase cells demonstrating the positive effect on yeast survival without activation of major antioxidant enzymes.     

Antifungal, acetylcholinesterase inhibition, antioxidant and phytochemical properties of three Barleria species

This study was aimed at evaluating the antifungal, acetylcholinesterase inhibition and antioxidant activities of petroleum ether, dichloromethane, ethanol and methanol extracts from different parts of Barleria prionitis, Barleria greenii and Barleria albostellata. Their phytochemical properties and the possibility of plant-part substitution as a conservation strategy against destructive harvesting (use of aerial parts and roots) of these species for medicinal purposes were also investigated. Microtitre plate assays were used in determining their antifungal (against Candida albicans) and acetylcholinesterase inhibition activities. All the extracts demonstrated both fungistatic and fungicidal activities with the minimum inhibitory concentration ranging from 0.78 to 9.38 mg/ml and minimum fungicidal concentration ranging from 1.17 to 12.50 mg/ml. The higher inhibitory activity of B. greenii leaf extracts in most cases compared to similar extracts of the stems and roots suggest the potential of B. greenii leaves in plant-part substitution. At the lowest extract concentration (0.156 mg/ml), the leaf extract of B. greenii demonstrated a significantly higher acetylcholinesterase (AChE) inhibition than its stem and root extracts. In B. albostellata, the AChE inhibitory activity demonstrated by the stem was significantly greater than that recorded in its leaf extract. These findings suggest that the idea of plant part substitution may be species and/or biological activity dependent. In the DPPH radical scavenging assay, different parts of Barleria species showed free radical scavenging activity with EC₅₀ values ranging from 6.65 to 12.56 μg/ml. The ability of the extracts from different plant parts to reduce ferric ion/ferricyanide complex to the ferrous form and decrease carotenoid bleaching rate suggests the presence of antioxidant compounds capable of donating electrons and hydrogen atoms in their reaction mechanisms. Flavonoids, iridoids and tannins were detected in the different parts of these Barleria species. These phytochemicals might be responsible for the observed biological activities. The isolation of specific bioactive compounds through bioassay-guided fractionation and their characterization as well as studies evaluating their safety may be necessary in the exploration of these species for potential new therapeutic drugs or drug leads.     

Genetic diversity in a germplasm collection of roseroot (Rhodiola rosea) in Norway studied by AFLP

Rhodiola rosea is widely distributed in Norway, but so far limited knowledge exists on the level of genetic diversity. To initiate a selective breeding program, Amplified Fragment Length Polymorphism (AFLP) analysis was used to estimate genetic diversity within the Norwegian R. rosea germplasm collection. AFLP analysis of 97 R. rosea clones using five primer combinations gave a total of 109 polymorphic bands. We detected high percentage of polymorphic bands (PPB) with a mean of 82.3% among the clones of R. rosea. Each of the 97 R. rosea clones could be unambiguously identified based on these primer combinations. Estimates of genetic similarities were obtained by the Dice coefficient, and a final dendrogram was constructed with the Unweighted Pair Group Method with Arithmetic mean (UPGMA). Genetic similarity based on the AFLP data ranged from 0.440 to 0.950 with a mean of 0.631. This genetic analysis showed that there was no close genetic similarity among clones related to their original growing county. No gender-specific markers were found in the R. rosea clones. Analysis of molecular variance (AMOVA) revealed a significantly greater variation within regions (92.03%) than among regions (7.97%). A low level of genetic differentiation (F_ST = 0.043) was observed, indicating a high level of gene flow, which had a strong influence on the genetic structure at different counties. Our results indicate high gene flow among R. rosea clones that might be a result of seed dispersal rather than cross-pollination. Further world-wide studies are required to compare the level of genetic diversity and more studies in R. rosea detailing the consequences of different patterns of gene flow (pollen spread and dispersal of seeds and clonal plants) will be useful for characterization of roseroot.     

Newbouldiosides A-C, phenylethanoid glycosides from the stem bark of Newbouldia laevis

From the stem bark of Newbouldia laevis three phenylethanoid glycosides, designated as newbouldioside A-C, were isolated together with a sodium salt of analogue B and the known compounds, verbascoside, 5-hydroxydehydro-iso-alpha-lapachone, 3,8-dihydroxydehydro-iso-alpha-lapachone, apigenin and luteolin. The structures of the phenylethanoid glycosides were elucidated by spectroscopic methods as beta-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-beta-D-glucopyranoside, ss-(3,4-dihydroxyphenyl)ethyl 5-O-syringoyl-beta-D-apiofuranosyloxy-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->3)]-6-O-E-feruloyl-beta-D-glucopyranoside, and beta-(3,4-dihydroxyphenyl)ethyl 3-O-E-feruloyl-beta-D-apiofuranosyloxy-(1-->2)-O-alpha-L-rhamnopyranosyl-(1-->2)-6-O-E-sinapoyl-beta-D-glucopyranoside, respectively.     

Phytochemical analysis and genetic characterization of six Hypericum species from Serbia

The secondary metabolite contents and genetic profiles of six Hypericum species (H. barbatum Jacq., H. hirsutum L., H. linarioides Bosse, H. maculatum Crantz, H. rumeliacum Boiss. and H. tetrapterum Fries), collected from different locations in Serbia, have been analyzed. Methanol extracts of the aerial parts of the plants were obtained by accelerated solvent extraction (ASE) at 40 degrees C and 100 bar, and analyzed for five pharmacologically important standard constituents (hyperoside, quercitrin, pseudohypericin, hyperforin and hypericin) by LC-MS/MS. The highest content of hypericin and pseudohypericin was observed in the H. barbatum extract, while the highest content of hyperforin and quercitrin was found in the H. tetrapterum extract and the highest content of hyperoside in the H. maculatum extract. A literature survey shows that the above six Hypericum species, with the exception of H. maculatum, have not been previously genetically profiled. In order to correlate the chemical constituents of the species under investigation with their genetic factors, genetic profiling of these species was undertaken using the random amplification of polymorphic DNA (RAPD) and single sequence repeat (SSR) profiles of the above selected plants. Among the 52 random primers used for the initial screening, only 10 yielded polymorphic RAPD profiles. A total of 111 polymorphic markers were generated using these primers. The SSR analysis shows that 8 out of the 10 primers used were polymorphic. The correlation among the species under investigation using the two genetic markers was performed using Jaccuard's coefficients of similarity and a high correlation (r=0.99) was obtained. The main conclusion from the above data is that there exists a stronger correlation for secondary metabolite contents with RAPD data than with SSR data among the six Hypericum species from Serbia.     

三种外来入侵斑潜蝇种间竞争研究进展

美洲斑潜蝇、南美斑潜蝇、三叶斑潜蝇是危害蔬菜、花卉的世界性大害虫。不同种间相互更替或取代的现象时有发生。根据国内外相关研究报道,综述了对近年来3种斑潜蝇种间竞争的研究。对斑潜蝇种间更替和取代现象的分析显示,生殖干扰、新生物型的出现、天敌、生态位、寄主植物以及抗药性等因素可能是影响它们种间竞争的关键。以期为斑潜蝇种群演替研究及防治策略制定提供参考。     

Analysis of the genetic structure of Rhodiola rosea (Crassulaceae) using inter-simple sequence repeat (ISSR) polymorphisms

The genetic diversity and differentiation of eleven R. rosea populations from different parts of its wide area of occurrence were studied by ISSR markers. Using eight primers, 252 DNA fragments were generated, and 243 of those DNA fragments were found to be polymorphic, indicating a high genetic variability at the species level (P = 96.4%, h = 0.176, SI = 0.291). Relatively low levels of diversity were determined at the population level (P 30.6-59.1%, h 0.088-0.165, SI 0.137-0.257). AMOVA analysis revealed that the majority of the genetic variation was within populations (65.42%), and the variance among populations was 34.58%. Cluster analysis revealed two groups of R. rosea populations; these groups likely represent distinct evolutionary lines in the species, which are different in genetic structure, evolutionary history and chorological migration routes.     

The effectiveness and efficacy of Rhodiola rosea L.: A systematic review of randomized clinical trials

Objective

To critically assess the current evidence from randomized clinical trials (RCTs) for or against the effectiveness or efficacy of Rhodiola rosea.

Data sources

Systematic literature searches were performed in six electronic databases: AMED (1985-July 2009), CINAHL (1982-July 2009), The Cochrane Library (search in July 2009), EMBASE (1974-July 2009), MEDLINE (1950-July 2009) and Web of Science (searched in July 2009). No language restrictions were imposed. Reference lists of all retrieved articles were searched, and experts and manufacturers were contacted for unpublished RCT.

Review methods

RCTs testing the efficacy or effectiveness of mono-preparations of R. rosea as sole treatment administered orally against a control intervention in any human individual suffering from any condition or healthy human volunteers were included. Studies were selected, data extracted, and quality assessed by two independent reviewers.

Results

Eleven RCTs met the inclusion criteria; all were placebo-controlled. Six trials investigated the effects of R. rosea on physical performance, four on mental performance, and two in patients diagnosed with mental health condition. The methodological quality of most trials was moderate or good. Only few mild adverse events were reported.

Conclusion

R. rosea may have beneficial effects on physical performance, mental performance, and certain mental health conditions. There is, however, a lack of independent replications of the single different studies. Five of the 10 RCTs reached more than three points on the Jadad score (i.e., good quality). More research seems warranted.     

Antennal resolution of pulsed pheromone plumes in three moth species

Male antennae of Cadra cautella,Pectinophora gossypiella, and Spodoptera exigua were presented with 20-ms-duration pulses of their two-component pheromone at rates of 1 to 33 Hz. Fourier analyses of electroantennograms resolved the temporal structure of trains of pheromone filaments delivered at up to 33 Hz for C. cautella and S. exigua and 25 Hz for P. gossypiella. Pheromone components tested separately for each species were generally equivalent in filament resolution to complete blends. Ambient temperatures of 18, 23 and 28 °C affected filament resolution only slightly, with poorer ability to discriminate rapidly pulsed signals at 18 °C. The question of how, or indeed if, such frequencies are conserved beyond the peripheral nervous system, remains.     

Thermogenic capacity of three species of fruit-eating phyllostomid bats

This study evaluated the thermogenic capacity of three species of fruit-eating phyllostomid bats (Carollia perspicillata, Sturnira lilium and Artibeus lituratus) during the dry-cool and wet-warm seasons, by measuring changes in body mass, basal metabolic rate (BMR), maximal metabolic rate (MMR), nonshivering thermogenesis and shivering thermogenesis. Body mass was lower, on average, during the dry-cool season and all species of fruit-eating bats showed an increase in oxygen consumption after noradrenaline injection and after exposure to a He-O₂ atmosphere. However, the magnitude of this increase was similar in both seasons. BMR also did not vary between seasons. Although, our results showed for the first time that all three species studied were able to increase thermogenesis by both nonshivering and shivering thermogenesis, we did not find significant differences in any thermoregulatory variable measured when comparing data from the two different seasons. Probably the difference in the mean and variance of the temperature profile between seasons were not strong enough to alter the thermogenic capacity of these species. Furthermore, the use of alternative physiological (torpor) or behavioral (huddling) strategies might have alleviated the need to trigger energetic-costly thermogenic responses.