Galtonosides A-E: Antiproliferative and Antiplasmodial Cholestane Glycosides from Galtonia regalis.

An extract of Galtonia regalis from the Natural Products Discovery Institute showed moderate antiplasmodial activity, with an IC50 value less than 1.25 µg/mL. The two known cholestane glycosides 1 and 2 and the five new cholestane glycosides galtonosides A-E (3-7) were isolated after bioassay-directed fractionation. The structures of the new compounds were determined by interpretation of their NMR and mass spectra. Among these compounds, galtonoside B (4) displayed the most potent antiplasmodial activity, with an IC50 value of 0.214 µM against the drug-resistant Dd2 strain of Plasmodium falciparum.

Patterns of floral nectar standing crops allow plants to manipulate their pollinators.

'Pollination syndromes' involving floral nectar have eluded satisfactory evolutionary explanation. For example, floral nectars for vertebrate-pollinated plants average low sugar concentrations, while such animals prefer high concentrations, perplexing pollination biologists and arousing recent controversy. Such relationships should result from evolutionary games, with plants and pollinators adopting Evolutionarily Stable Strategies, and nectar manipulating rather than attracting pollinators. Plant potential to manipulate pollinators depends on relationships between neighbouring flowers within plants, for all nectar attributes, but this has not been investigated. We measured nectar volume, concentration and sugar composition for open flowers on naturally-growing Blandfordia grandiflora plants, presenting classic bird-pollinated plant syndrome. To evaluate potential pollinator manipulation through nectar, we analysed relationships between neighbouring flowers for nectar volume, concentration, proportion sucrose, log(fructose/glucose), and sugar weight. To evaluate potential attraction of repeat-visits to flowers or plants through nectar, we compared attributes between successive days. Nearby flowers were positively correlated for all attributes, except log(fructose/glucose) as fructose≈glucose. Most relationships between nectar attributes for flowers and plants on successive days were non-significant. Nectar-feeding pollinators should therefore decide whether to visit another flower on a plant, based on all attributes of nectar just-obtained, enabling plants to manipulate pollinators through adjusting nectar. Plants are unlikely to attract repeat pollinator-visits through nectar production. Floral nectar evolution is conceptually straightforward but empirically challenging. A mutant plant deviating from the population in attributes of nectar-production per flower would manipulate, rather than attract, nectar-feeding pollinators, altering pollen transfer, hence reproduction. However, links between floral nectar and plant fitness present empirical difficulties.

A novel process for asparagus polyphenols utilization by ultrasound assisted adsorption and desorption using resins.

The ultrasound assisted purification of asparagus polyphenols by adsorption and desorption on the macroporous resins was investigated. The ultrasound within the selected intensities (12-120 W) and temperatures (25-35 °C) increased the adsorption and desorption capacities of asparagus polyphenols on D101 resins. Higher ultrasound intensity (120 W) and lower temperature (25 °C) benefited the adsorption process and the adsorption capacity of total polyphenols after ultrasound was 3.95 mg/g, which was 2 times than that obtained after shaking at 120 rpm. Meanwhile, ultrasound can significantly shorten the equilibrium time and the adsorption process of asparagus polyphenols could be well described by Pseudo-second order model and Freundlich model. Stereoscopic microscope was first used to investigate the microstructure characterization of resins, indicating that ultrasound mainly enhanced the surface roughness of resins. Interestingly, rutin possessed the highest adsorption capacities and ferulic acid had the highest the desorption capacities among the studied individual polyphenols. The obtained results evidenced on a progressive insight of application of ultrasound assisted resins for purification of asparagus polyphenols.

Studies on antidiarrheal and laxative activities of aqueous-ethanol extract of Asphodelus tenuifolius and underlying mechanisms.

BACKGROUND: Asphodelus tenuifolius Cav. (Asphodelaceae) has traditional reputability in treatment of diarrhea and constipation but no scientific study has been reported for its gastrointestinal effects. Present study was conducted to evaluate antidiarrheal and laxative activities of the plant. METHODS: Aqueous-ethanol crude extract of Asphodelus tenuifolius (At.Cr) was subjected to phytochemical screening and liquid-liquid fractionation. In vivo studies of charcoal meal intestinal transit test, antidiarrheal activity against castor oil induced diarrhea and laxative activity were performed in mice. In vitro experiments were conducted upon rabbit jejunum preparations using standard tissue bath techniques. RESULTS: Phytochemical screening indicated presence of alkaloids, anthraquinones, flavonoids, saponins, steroids, tannins and phenols in At.Cr. In charcoal meal intestinal transit test, At.Cr increased (p < 0.001) intestinal motility at 100 mg/kg dose, but decreased (p < 0.001) it at 500 mg/kg dose, when compared to the control group. At.Cr (300-700 mg/kg) provided protection from castor oil induced diarrhea in mice, which was significant (p < 0.001) at 500 and 700 mg/kg doses, as compared to the saline treated control group. At.Cr (50 and 100 mg/kg) enhanced total and wet feces counts in normal mice, as compared to saline treated control. In jejunum preparations, At.Cr inhibited spontaneous, K+ (80 mM) and K+ (25 mM) mediated contractions, similar to verapamil. Pre-incubation of jejunum preparations with At.Cr resulted in rightward nonparallel shift in Ca+ 2 concentration response curves, similar to verapamil. The spasmolytic activity was concentrated in ethylacetate fraction. Aqueous fraction exhibited spasmogenicity upon spontaneous contractions, which was blocked in presence of verapamil, but remained unaffected by other tested antagonists. CONCLUSION: The Asphodelus tenuifolius crude extract possesses gut modulatory activity, which may normalize gut functions in diarrhea and constipation. The spasmolytic activity of the extract was found to be mediated through Ca+ 2 channel blocking action. The spasmogenic activity, found partitioned in aqueous fraction, possibly involves Ca+ 2 influx through voltage gated Ca+ 2 channels. The study supports ethnic uses of the plant in diarrhea and constipation.

Anti-Inflammatory Properties of Bellevalia saviczii Root Extract and Its Isolated Homoisoflavonoid (Dracol) Are Mediated by Modification on Calcium Signaling.

Bellevalia saviczii is a medicinal plant used as anti-rheumatic and anti-inflammatory herbal remedy in Iraqi-Kurdistan. The aim of this study was to evaluate the anti-inflammatory activity of its extract and the isolated homoisoflavonoid (Dracol) by studying the Ca2+-dependent NF-kB pathway. Nuclear translocation of p65 NF-kB subunit, as parameter of NF-kB activation, was visualized in human leukemic monocytes by immunofluorescence and Western blot analyses, after cell treatment with B. saviczii root extract or Dracol followed by Lipopolysaccharide stimulation. In parallel, Ca2+ signals responsible for NF-kB activation and levels of inflammatory cytokines were investigated. LPS-induced p65 translocation was evident in monocytes and both treatments, in particular that with Dracol, were able to counteract this activation. Intracellular Ca2+ oscillations were halted and the cytokine release reduced. These results confirm the traditional anti-inflammatory efficacy of B. saviczii and identify one of the molecules in the extract which appears to be responsible of this action.

A water-soluble polysaccharide from the roots of Eremurus spectabilis M. B. subsp. spectabilis: Extraction, purification and structural features.

A heteropolysaccharide ESP, was separated from a water extract of dried roots of Eremurus spectabilis by column chromatographies on DEAE-cellulose A52 and Sephadex G-100. Specific optical rotation, molecular mass and total carbohydrate content of ESP were -36.3°, 43.8 kDa and 97.2%, respectively. Monosaccharide composition analysis showed that ESP consisted of glucose and mannose at a molar ratio of 1.0:2.9. Structural characterization of ESP was done by various chemical and instrumental techniques (methylation, partial acid hydrolysis, Smith degradation, periodate oxidation, GLC-MS and 1D/2D NMR). The repeating unit of ESP was determined as following.

Geodorum densiflorum rhizome lectin inhibits Ehrlich ascites carcinoma cell growth by inducing apoptosis through the regulation of BAX, p53 and NF-κB genes expression.

A lectin with a molecular mass of 12 ±â€¯1 kDa was isolated for the first time from Geodorum densiflorum (Lam.) rhizome (GDL). The lectin exhibited hemagglutination activity both in mice and human erythrocytes which was inhibited by 4-nitrophenyl-ß-D-glucopyranoside among the tested 26 sugars. The lectin was heat stable and showed its full activity in the pH range from 5.0 to 9.0. The lectin did not lose its activity in the presence of urea but the activity lost significantly when treated with EDTA. Divalent cation Ca2+ and Mg2+ also partially inhibited the activity of the lectin. The lectin strongly agglutinated Ehrlich ascites carcinoma (EAC) and inhibited the cells growth by 60% at 160 µg/ml protein concentration but unable to inhibit the growth of HeLa cells in vitro. The growth inhibition was due to the induction of apoptosis in the EAC cells which was confirmed by annexin-V and caspase-3 substrate and finally by apoptosis-related genes expression. An intensive expression of anti-apoptotic Bcl-X gene was observed only in untreated EAC cells while pro-apoptotic Bak and Bax genes expressed only in GDL treated EAC cells with the remarkable increase of the p53 gene expression. In the treated EAC cells NFκB expression was down regulated.

Manipulation of molecular pathways and senescence hallmarks by natural compounds in fibroblast cells.

Aging contributes to an increased risk of developing a number of neurodegenerative and chronic disorders, predominantly related to oxidative stress (OS) and defects in the antioxidant balance. This study focused on the antisenescence effect of four plant species (Falcaria vulgaris, Ixiolirion tataricum, Ajuga chamaecistus, and Scabiosa flavida) on H2 O2 -induced premature senescence in rat NIH3T3 fibroblasts, which were found to be rich in effective phytochemicals with traditional ethnobotanical backgrounds. Plant materials were collected, identified, and extracted. To determine the viability of NIH3T3 cells, an MTT assay was conducted. The levels of OS markers and the senescence-associated ß-galactosidase (SA-ß-GAL) activity were analyzed by the Elisa reader. The cell cycle pattern was evaluated by flow cytometry. The expression of senescence-related inflammatory cytokines and the molecules involved in aging signaling pathways were investigated using the real-time reverse transcription polymerase chain reaction (RT-PCR). H2 O2 treatment decreased cell viability and increased lipid peroxidation (LPO) and the reactive oxygen species (ROS) in NIH3T3s. However, S. flavida exhibited low cytotoxicity, reduced OS and SA-ß-GAL activities in NIH3T3 cells compared with the H2 O2 -treated group. I. tataricum was the second best plant, although it was more toxic to NIHT3T cells. S. flavida decreased G0/G1 arrest and facilitated the G2/M transition of NIH3T3s, also downregulated the expression of p38, p53, p16, and the related inflammatory mediators. S. flavida potentially modulated senescence-associated hallmarks in fibroblasts exposed to H2 O2 , thus it may inhibit the aging process via controlling the OS. Therefore it is a promising candidate for future antiaging explorations.

Antiplasmodial alkaloids from bulbs of Amaryllis belladonna Steud.

A bioassay-guided fractionation and chemical investigation of Amaryllis belladonna Steud. bulbs resulted in the isolation and identification of the new crinane alkaloid 1,4-dihydroxy-3-methoxy powellan (1), along with the 3 known crinane alkaloids 2-4 and the two lycorane alkaloids 5-6. The structures were elucidated by interpretation of combined HR-ESIMS, CD and 2D NMR spectroscopic data. Among these isolated compounds the lycorane-type alkaloid acetylcaranine (5) exhibited strong antiplasmodial activity, while compounds 3 and 4 were moderately active, and compounds 1 and 6 were inactive.

Multicomponent pattern and biological activities of seven Asphodeline taxa: potential sources of natural-functional ingredients for bioactive formulations.

The current study was carried out to evaluate multicomponent pattern, biological and enzymatic activities of seven Asphodeline taxa root extracts as useful ingredients, due to the fact that these plants are commonly used as traditional food supplements in Turkish regions. The extracts were characterized for free anthraquinones and phenolics to obtain a specific chemical fingerprint useful for quality control. These analyzes were coupled to biological and enzymatic activities in order to obtain comprehensive information of the natural product. Free anthraquinones and phenolics were determined using validated HPLC-PDA methods. Antioxidant properties were determined by different procedures including free radical scavenging, reducing power, phosphomolybdenum and metal chelating assays. Ames assay was performed to evaluate mutagenic/antimutagenic properties. Enzyme inhibitory activities were tested against cholinesterase, tyrosinase, α-amylase and α-glucosidase. From the herein reported results, Asphodeline could be valuable for the production of bioactive products or food supplements for cosmetic and pharmaceutical industries.

Structural diversity of xylans in the cell walls of monocots.

MAIN CONCLUSION: Xylans in the cell walls of monocots are structurally diverse. Arabinofuranose-containing glucuronoxylans are characteristic of commelinids. However, other structural features are not correlated with the major transitions in monocot evolution. Most studies of xylan structure in monocot cell walls have emphasized members of the Poaceae (grasses). Thus, there is a paucity of information regarding xylan structure in other commelinid and in non-commelinid monocot walls. Here, we describe the major structural features of the xylans produced by plants selected from ten of the twelve monocot orders. Glucuronoxylans comparable to eudicot secondary wall glucuronoxylans are abundant in non-commelinid walls. However, the α-D-glucuronic acid/4-O-methyl-α-D-glucuronic acid is often substituted at O-2 by an α-L-arabinopyranose residue in Alismatales and Asparagales glucuronoxylans. Glucuronoarabinoxylans were the only xylans detected in the cell walls of five different members of the Poaceae family (grasses). By contrast, both glucuronoxylan and glucuronoarabinoxylan are formed by the Zingiberales and Commelinales (commelinids). At least one species of each monocot order, including the Poales, forms xylan with the reducing end sequence -4)-ß-D-Xylp-(1,3)-α-L-Rhap-(1,2)-α-D-GalpA-(1,4)-D-Xyl first identified in eudicot and gymnosperm glucuronoxylans. This sequence was not discernible in the arabinopyranose-containing glucuronoxylans of the Alismatales and Asparagales or the glucuronoarabinoxylans of the Poaceae. Rather, our data provide additional evidence that in Poaceae glucuronoarabinoxylan, the reducing end xylose residue is often substituted at O-2 with 4-O-methyl glucuronic acid or at O-3 with arabinofuranose. The variations in xylan structure and their implications for the evolution and biosynthesis of monocot cell walls are discussed.

[Analysis of the ITS1/ITS2 nuclear spacers and the secondary structure of 5.8S rRNA gene in endemic species Bellevalia sarmatica (Pall. ex Georgi) Woronow and related species of the subfamily scilloideae].

Sequence variability of the ITS spacers and 5.8S rRNA gene was examined in 11 accessions of the subfamily Scilloideae, including seven accessions of rare and endangered species Bellevalia sarmatica from Volgograd region. The intraspecific polymorphism level of the examined ITS1­5.8S­ITS2 sequence of B. sarmatica accessions constituted 1.3%. The phylogenetic position of B. sarmatica within the genus Bellevalia was determined. It was demonstrated that B. sarmatica belonged to the section Nutantes, and the most closely related species were B. webbiana and B. dubia. Nucleotide substitutions in the 5.8S rRNA gene sequence of the analyzed Scilloideae accessions were identified and studied. The predicted secondary structure of 5.8S rRNA gene was constructed. It was demonstrated that in the examined accessions, mutations in the 5.8S rRNA gene were mainly localized in the third hairpin region and had no effect on the secondary structure of the 5.8S rRNA molecule.