49 research outputs found
Plant Extracts as Antimicrobial Agents in Sustainable Conservation of Erythrina caffra (Fabaceae) Historical Trees
Microbial colonization plays a relevant role in the biodegradation and biodeterioration of cultural and natural heritage, representing a revealing problem in conservation strategy. In this study, the essential oil (EO) and hydro-alcoholic extract (HAE) of Origanum vulgare L. (Lamiaceae),
an aromatic perennial plant, representative of the Mediterranean basin, growing spontaneously and cultivated all over the world, were analysed. Natural products, such as essential oil and hydroalcoholic extract, have strong antiseptic and antimicrobial properties and are ad hoc applied for the sustainable conservation of Erithryna caffra (Fabaceae). The main taxa revealed in the damaging of these arboreal heritage, are Bacillus sp., Streptomyces sp. and Terribacillus sp. (as bacteria), Alternaria sp., Aspergillus sp. and Chaetomium sp. (as fungi). GS-MS analysis identified carvacrol, thymol and their biosynthetic precursors g-terpinene and p-cymene, as main components, and the antimicrobial efficiency assayed by in vitro methods (Agar Dish Diffusion, Well Plate Diffusion). In this study, by combining the application/exposure of both HAE and EO, the bacterial and fungal colonies development has been in vitro countered. The results confirm the possible use of plant products as a valid alternative to the traditional synthetic chemical biocides, with full respect to the environment
Cytoprotective effect of preparations from various parts of Punica granatum L. fruits in oxidatively injured mammalian cells in comparison with their antioxidant capacity in cell free systems
none9Pomegranate (Punica granatum L.) juice (PJ) is being increasingly proposed as a nutritional supplement to prevent atherosclerosis in humans. This therapeutically valuable potential has been attributed to PJ antioxidant capacity which has been mostly tested by means of cell-free assays: indeed, to the best of our knowledge, no study has focused on the direct antioxidant capacity of PJ in cultured cells. Here, the antioxidant capacity in cell free-systems of preparations from various parts of pomegranate has been compared with their cytoprotective – bona fide antioxidant – activity in cultured human cells (U937 promonocytes and HUVEC endothelial cells) exposed to an array of oxidizing agents. Pomegranate derivatives were PJ, arils only juice (AJ) and aqueous rinds extract (RE). In cell-free assays – 1,1-diphenyl-2-picrylhydrazyl (DPPH), chemiluminescence luminol/xanthine/xanthine oxidase and lipoxygenase assays – all the preparations displayed good antioxidant capacity, the relative potency order being RE > PJ > AJ. On the contrary, only RE was capable of preventing the deleterious effects – cytotoxicity, DNA damage and depletion of non protein sulphydrils (NPSH) pool – caused by treatment of cells with H2O2, tert-butylhydroperoxide (tB-OOH) or oxidized lipoproteins (Ox-LDL) via a mechanism which is likely to involve both direct scavenging of radical species and iron chelation. Surprisingly, AJ and PJ slightly sensitized cells to the cytotoxic effects of the three agents. Then it would appear that AJ, the major and tasty part of PJ, does not contain ellagic acid and punicalagin (i.e. the polyphenols highly represented in RE which are reputed to be responsible for the antioxidant capacity) in amounts sufficient to exert cytoprotection in oxidatively injured, living cells. Based on these results, the development and evaluation of rinds-only based derivatives for antiatherogenic preventive purposes in humans should be encouraged.openSESTILI P; MARTINELLI C; RICCI D; FRATERNALE D; BUCCHINI A; GIAMPERI L; CURCIO R; PICCOLI G; STOCCHI V.Sestili, Piero; Martinelli, Chiara; Ricci, Donata; Fraternale, Daniele; Bucchini, ANAHI ELENA ADA; Giamperi, Laura; Curcio, R; Piccoli, Giovanni; Stocchi, Vilbert
The quest for the solar g modes
Solar gravity modes (or g modes) -- oscillations of the solar interior for
which buoyancy acts as the restoring force -- have the potential to provide
unprecedented inference on the structure and dynamics of the solar core,
inference that is not possible with the well observed acoustic modes (or p
modes). The high amplitude of the g-mode eigenfunctions in the core and the
evanesence of the modes in the convection zone make the modes particularly
sensitive to the physical and dynamical conditions in the core. Owing to the
existence of the convection zone, the g modes have very low amplitudes at
photospheric levels, which makes the modes extremely hard to detect. In this
paper, we review the current state of play regarding attempts to detect g
modes. We review the theory of g modes, including theoretical estimation of the
g-mode frequencies, amplitudes and damping rates. Then we go on to discuss the
techniques that have been used to try to detect g modes. We review results in
the literature, and finish by looking to the future, and the potential advances
that can be made -- from both data and data-analysis perspectives -- to give
unambiguous detections of individual g modes. The review ends by concluding
that, at the time of writing, there is indeed a consensus amongst the authors
that there is currently no undisputed detection of solar g modes.Comment: 71 pages, 18 figures, accepted by Astronomy and Astrophysics Revie
Chemical Composition and Antifungal Activity of Essential Oil Obtained from In Vitro Plants of Thymus mastichina L.
Essential oil composition and antioxidant activity of peels of Citrus sinensis blood and blond and Citrus aurantium
The essential oil from Bupleurum fruticosum L. of the Cyrenaica Region of eastern Libya and the problem of bupleurol
Squalene content and antioxidant activity of Sambucus nigra flowers extracts obtained by FE
Antioxidant activity of Citrus paradisi seeds glyceric extract.
none4noneL. GIAMPERI; D. FRATERNALE; A. BUCCHINI; RICCI D.Giamperi, Laura; Fraternale, Daniele; Bucchini, ANAHI ELENA ADA; Ricci, Donat