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Markus Veit - One of the best experts on this subject based on the ideXlab platform.
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styrylpyrone biosynthesis in Equisetum arvense
Phytochemistry, 1997Co-Authors: Cornelia Beckert, Christian Horn, Jorgpeter Schnitzler, Andrea Lehning, Werner Heller, Markus VeitAbstract:Abstract Styrylpyrone synthase was detected in cell free extracts from gametophytes of Equisetum arvense . This new enzyme catalyses the formation of styrylpyrones from malonyl-CoA and hydroxycinnamoyl-CoA precursors. A standard enzyme assay was established. The enzyme activity was characterized in partially purified protein extracts. p -Coumaroyl-CoA was accepted as substrate at pH 6.0–8.5 in various buffer systems with the formation of bisnoryangonin, and optimum enzyme activity was observed in potassium phosphate buffer at pH 7.5. Caffeoyl-CoA was accepted as substrate only in potassium phosphate buffer at pH 6.0–7.5 with formation of hispidin; optimum enzyme activity was observed at pH 7.0. The apparent K m values were 220 μM for caffeoyl-CoA and 230 μM for p -coumaroyl-CoA. The temperature optimum of the enzyme activity was 37° for bisnoryangonin and 30° for hispidin formation. Molecular weight determination by FPLC indicated that this protein has a native molecular weight of ca 56–77 kDa. Styrylpyrones accumulate in rhizomes of sporophytes and gametophytes of E. arvense as major constitutive metabolites. In these organs no flavonoids could be detected. In green sprouts, styrylpyrone accumulation is only detected as a local response to mechanical wounding or microbial attack, and flavonoids are accumulated as major polyketide metabolites. Thus, chalcone synthase is active in the sporophytes and might have developed in the course of evolution from styrylpyrone synthase present in the more primitive gametophytes.
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Equisetumpyrone, a styrylpyrone glucoside in gametophytes from Equisetum arvense
Phytochemistry, 1993Co-Authors: Markus Veit, Hans Geiger, Victor Wray, Ahmed A. Abou-mandour, Wolfgang Rozdzinski, Ludger Witte, Dieter Strack, Franz-christian CzyganAbstract:Abstract A new styrylpyrone was isolated from vegetative gametophytes of Equisetum arvense. Its structure was determined spectroscopically to be 3,4-dihydro
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Di-E-caffeoyl-meso-tartaric acid in the barren sprouts of Equisetum arvense
Phytochemistry, 1991Co-Authors: Markus Veit, Victor Wray, Dieter Strack, Franz-c. Czygan, Ludger WitteAbstract:Abstract Di-E-caffeoyl-meso-tartaric acid was isolated from the methanolic extract of the barren sprouts of Equisetum arvense as the main hydroxycinnamic acid derivative. The structure was elucidated spectroscopically and the spectral data are compared with those of the known di E-caffeoyl-(2S-3S)-(−)-tartaric acid (chicoric acid). It is a marker compound for E.arvense; its concentration over a two year growth period is reported.
O Soriţău - One of the best experts on this subject based on the ideXlab platform.
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Equisetum arvense l extract induces antibacterial activity and modulates oxidative stress inflammation and apoptosis in endothelial vascular cells exposed to hyperosmotic stress
Oxidative Medicine and Cellular Longevity, 2018Co-Authors: A Pallag, Gabriela Adriana Filip, Diana Olteanu, Simona Clichici, Ioana Baldea, Tunde Jurca, Otilia Micle, Laura Vicas, Eleonora Marian, O SoriţăuAbstract:Background. The antimicrobial activity of the Equisetum arvense L. extract and the mechanisms involved in the in vitro effects on endothelial vascular cells exposed to hyperosmotic stress were evaluated. Methods. Antimicrobial activity was evaluated by disk diffusion method and minimum inhibitory concentration (MIC) determination, and oxidative stress, inflammation, and apoptosis, in pretreatment with Equisetum arvense L., caffeic acid, and cathechin, were quantified. Results. The results have shown that Equisetum arvense L. exhibited antibacterial effects only on pathogenic gram-positive cocci. The modulatory activity of Equisetum arvense L. on endothelial cells exposed to hypertonic medium was different and depended on the concentration used. Low concentrations of tested compounds exerted antioxidant effect and diminished the activity of caspase-8 and also increased IκB expression while in high doses, Equisetum arvense L. was prooxidant, induced apoptosis, and decreased IL-6 secretion. Conclusions. These experimental findings suggest that Equisetum arvense L. has antibacterial effects on gram-positive cocci and, administered in low dose, may be a new therapeutic approach for diseases associated with hypertonic conditions or oxidative stress and apoptosis.
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Equisetum arvense l extract induces antibacterial activity and modulates oxidative stress inflammation and apoptosis in endothelial vascular cells exposed to hyperosmotic stress
Oxidative Medicine and Cellular Longevity, 2018Co-Authors: A Pallag, Gabriela Adriana Filip, Diana Olteanu, Simona Clichici, Ioana Baldea, Tunde Jurca, Otilia Micle, Laura Vicas, Eleonora Marian, O SoriţăuAbstract:Background. The antimicrobial activity of the Equisetum arvense L. extract and the mechanisms involved in the in vitro effects on endothelial vascular cells exposed to hyperosmotic stress were evaluated. Methods. Antimicrobial activity was evaluated by disk diffusion method and minimum inhibitory concentration (MIC) determination, and oxidative stress, inflammation, and apoptosis, in pretreatment with Equisetum arvense L., caffeic acid, and cathechin, were quantified. Results. The results have shown that Equisetum arvense L. exhibited antibacterial effects only on pathogenic gram-positive cocci. The modulatory activity of Equisetum arvense L. on endothelial cells exposed to hypertonic medium was different and depended on the concentration used. Low concentrations of tested compounds exerted antioxidant effect and diminished the activity of caspase-8 and also increased IκB expression while in high doses, Equisetum arvense L. was prooxidant, induced apoptosis, and decreased IL-6 secretion. Conclusions. These experimental findings suggest that Equisetum arvense L. has antibacterial effects on gram-positive cocci and, administered in low dose, may be a new therapeutic approach for diseases associated with hypertonic conditions or oxidative stress and apoptosis.
Thomas Gerber - One of the best experts on this subject based on the ideXlab platform.
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structure of silica in Equisetum arvense
Analytical and Bioanalytical Chemistry, 2003Co-Authors: Gerd Holzhuter, K Narayanan, Thomas GerberAbstract:Silicified regions in the stem and leaf of the horsetail Equisetum arvense were studied by scanning and transmission electron microscopy. The silica was present as a thin layer on the outer surface with variation in the size of this layer depending on the part investigated. There was a dense arrangement of silica spheres with some density fluctuations. A loose arrangement of silica particles with variation in their size was found beneath this dense arrangement suggesting the agglomeration of silica. An electron diffraction pattern showed the presence of amorphous silica, with the short range order being comparable to that of silica from other chemical sources. The medium range order shows the presence of silica with a high inner surface. SAXS measurements correlate with the particle size observed in TEM, and provide values for surface fractals. A new method of plasma ashing to remove the organics is also described.
Sina Haghanifar - One of the best experts on this subject based on the ideXlab platform.
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Effect of Equisetum arvense extract on bone mineral density in Wistar rats via digital radiography.
Caspian journal of internal medicine, 2019Co-Authors: Nazanin Arbabzadegan, Ali Akbar Moghadamnia, Shohrab Kazemi, Farideh Nozari, Ehsan Moudi, Sina HaghanifarAbstract:Background Osteoporosis is a common disease of old age. The present study used digital radiography to determine the effects of Equisetum arvense extract on the bone mineral density (BMD) of experimental rats. Methods In this experimental study, 25 male and 25 female Wistar rats, aged three weeks old and weighing 100 grams, were randomly divided into five groups: (1) control group, (2) calcium/vitamin D group, (3) 60 mg/kg Equisetum arvense extract group, (4) 90 mg/kg Equisetum arvense extract group and (5) 120 mg/kg Equisetum arvense extract group. Rats received these diets for 30 days. The spongy bone density was measured in the maxilla and mandible using digital radiography and the serum levels of calcium, vitamin D and phosphorus were measured at baseline and after 30 days. The data were analyzed using ANOVA and Tukey test. Results There was no significant difference between serum calcium and phosphorus levels in the five groups before and after 30 days. The serum vitamin D in the group receiving calcium and vitamin D was significantly higher than in the other groups (with average values of 24.7, 61.7, 23.47, 23.95 and 39.16 in the male groups 1 to 5 and 29.0, 85.07, 31.58, 42.34 and 18.83 in the female groups 1 to 5, respectively (p
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effect of Equisetum arvense extract on bone mineral density in wistar rats via digital radiography
caspian journal of internal medicine, 2019Co-Authors: Nazanin Arbabzadegan, Ali Akbar Moghadamnia, Shohrab Kazemi, Farideh Nozari, Ehsan Moudi, Sina HaghanifarAbstract:Background Osteoporosis is a common disease of old age. The present study used digital radiography to determine the effects of Equisetum arvense extract on the bone mineral density (BMD) of experimental rats. Methods In this experimental study, 25 male and 25 female Wistar rats, aged three weeks old and weighing 100 grams, were randomly divided into five groups: (1) control group, (2) calcium/vitamin D group, (3) 60 mg/kg Equisetum arvense extract group, (4) 90 mg/kg Equisetum arvense extract group and (5) 120 mg/kg Equisetum arvense extract group. Rats received these diets for 30 days. The spongy bone density was measured in the maxilla and mandible using digital radiography and the serum levels of calcium, vitamin D and phosphorus were measured at baseline and after 30 days. The data were analyzed using ANOVA and Tukey test. Results There was no significant difference between serum calcium and phosphorus levels in the five groups before and after 30 days. The serum vitamin D in the group receiving calcium and vitamin D was significantly higher than in the other groups (with average values of 24.7, 61.7, 23.47, 23.95 and 39.16 in the male groups 1 to 5 and 29.0, 85.07, 31.58, 42.34 and 18.83 in the female groups 1 to 5, respectively (p<0.001). Moreover, the increased mandibular BMD in the 120 mg/kg Equisetum arvense group was significantly higher than in the control group (p<0.01). Conclusion A diet containing 120 mg/kg Equisetum arvense extract resulted in increased mandibular bone mineral density.
Carole C Perry - One of the best experts on this subject based on the ideXlab platform.
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isolation of a wide range of minerals from a thermally treated plant Equisetum arvense a mare s tale
Journal of Biological Inorganic Chemistry, 2016Co-Authors: Anna Solarabada, Julia Rinck, David J Belton, Annie K Powell, Carole C PerryAbstract:Silica is the second most abundant biomineral being exceeded in nature only by biogenic CaCO3. Many land plants (such as rice, cereals, cucumber, etc.) deposit silica in significant amounts to reinforce their tissues and as a systematic response to pathogen attack. One of the most ancient species of living vascular plants, Equisetum arvense is also able to take up and accumulate silica in all parts of the plant. Numerous methods have been developed for elimination of the organic material and/or metal ions present in plant material to isolate biogenic silica. However, depending on the chemical and/or physical treatment applied to branch or stem from Equisetum arvense; other mineral forms such glass-type materials (i.e. CaSiO3), salts (i.e. KCl) or luminescent materials can also be isolated from the plant material. In the current contribution, we show the chemical and/or thermal routes that lead to the formation of a number of different mineral types in addition to biogenic silica.
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Silica deposition and ultrastructure in the cell wall of Equisetum arvense: the importance of cell wall structures and flow control in biosilicification?
Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 1991Co-Authors: Carole C Perry, M. A. FraserAbstract:Scanning and transmission electron microscopy have been used in the investigation of the surface micromorphology and ultrastructure of silicas extracted from different regions of the horsetail Equisetum arvense . The surface micromorphology was found to be very complex and varied with the anatomical region of the plant. Principally fibrillar, globular and sheet-like ultrastructural motifs of silica were observed, their proportions and detailed structure also varying with the anatomical region studied. The physiocochemical mechanisms by which these structural motifs arise are discussed in relation to the surface micromorphologies observed and to their anatomical function.