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- Nieira-Carrillo, Andronico, et al.
(författare)
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Calcium carbonate growth modification by constituents releases from porous cellulose filter membranes
- 2008
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Ingår i: Journal of the Chilean Chemical Society (Print). - 0717-9324 .- 0717-9707. ; 53:2, s. 1469-1473
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Tidskriftsartikel (refereegranskat)abstract
- Filtration of a suspension of calcium carbonate (CaCO3) or other inorganic solutions are often part of the methodology for recovering crystals during biomimetic mineralization experiments performed by various procedures. However, the use of cellulose filter membranes (FM) may cause a problem in in vitro crystallization experiments, because constituents released from the filters into the filtrates can alter the morphology of CaCO3 crystals. Therefore, it is possible to misinterpret data obtained when the effect of specific additives tested in the investigation of biomineralization mechanisms. Herein, we present essential information to avoid such misinterpretations of data obtained from mineralization experiments. CaCO3, was precipitated at room temperature by the gas diffusion method in the presence of FM as support and particularly as filtrates of calcium chloride (CaCl2) obtained from various commercial FM. The occurrence or absence of morphological modifications of the calcite and vaterite crystals obtained with different FM correlates well with the different elemental compositions of the solutions where crystals are grown because of the constituents released from the filters into the filtrate. X-ray photoelectron spectroscopy (XPS) data indicate significant differences in the filter elemental composition. We assume that the observed chronological changes in CaCO3 crystal modification could be due to incorporation into the calcite lattice of constituents released from the FM, most likely monomers, oligomers, or short-chain polymers.
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| 2. |
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| 3. |
- Aqueveque, Pedro, et al.
(författare)
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Antimicrobial activity of metabolites from mycelial cultures of Chilean Basidiomycetes
- 2006
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Ingår i: Journal of the Chilean Chemical Society. - 0717-9707. ; 51:4, s. 1059-1060
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Tidskriftsartikel (refereegranskat)abstract
- We reported seven compounds isolated from mycelial cultures of Chilean Basidiomycetes. The compound structures were elucidated by spectroscopic methods. Two polyacetylenes were isolated from Gymnopilus spectabilis: hepta-4,6-diyn-3-ol (1) and 7-chloro-hepta-4,6-diyn-3 ol (2). We isolated the aromatic compounds p-anisaldehyde (3) and 3-chloro-p-anisaldehyde (4) from Hypholoma capnoides. H. fasciculare produced the compounds (3), (4), 3,5-dichloro-4-metoxi-benzyl alcohol (5) and the sesquiterpen naematolon (6). Finally, H. sublateritium produced (5) and another sesquiterpen, marasmal (7). The compounds (1), (2), (5), and (7) showed biological activity against the tested model microorganism.
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| 4. |
- Bravo-Arrepol, Gastón, et al.
(författare)
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ISOLATED LIGNANS OF ARAUCARIA ARAUCANA (MOLINA) K. KOCH PROVIDE WOOD PROTECTION AGAINST ATTACK BY THE XYLOPHAGOUS FUNGUS PLEUROTUS OSTREATUS (JACQ.) P. KUMM
- 2023
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Ingår i: Journal of the Chilean Chemical Society. - 0717-9324. ; 68:2, s. 5871-5875
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Tidskriftsartikel (refereegranskat)abstract
- Araucaria araucana (Molina) K. Koch is an evergreen conifer endemic of Southern Chile and it is considered a sacred tree by the Pehuenche originary people. A. araucana is endangered in the red book. The knots wood of A. araucana are resistant to biological degradation, due to producing a high amount of lignans, even after the decomposition of the tree is possible to find its knots in the forest. In the present study the chemical composition of three wood tissue of A. araucana; knotwood, stemwood, and branches were analyzed by HPTLC-MS, GC-MS, and NMR. Three lignans were purified and identified as eudesmin (1), ((1S,2R,3R) 1,2,3,4-tetrahydrona phthalene-2,3-diyl) dimethanol (2) and secoisolarisiresinol (3). Folin-Ciocalteu, DPPH and resistance to biodegradation assays were evaluated to extracts from compressed wood zones. Eudesmin was identified as the principal lignan in knots with a 0.5%w/w and outperformed the fungicide Nipacide® P511 in protecting wood against xylophage fungi Pleurotus ostreatus (Jacq.) P. Kumm.
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