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51.
The lipidic extract of the seaweed Gracilariopsis longissima (Rhodophyta, Gracilariales): a potential resource for biotechnological purposes? 总被引:2,自引:0,他引:2
Stabili L Acquaviva MI Biandolino F Cavallo RA De Pascali SA Fanizzi FP Narracci M Petrocelli A Cecere E 《New biotechnology》2012,29(3):443-450
In recent years seaweeds increasingly attracted interest in the search for new drugs and have been shown to be a primary source of bioactive natural products including antibiotics. In the present investigation the antimicrobial activity of Gracilariopsis longissima lipidic extract was assayed and its chemical characterization was carried out by means of advanced analytical techniques such as gas-chromatography and multinuclear and multidimensional NMR spectroscopy. G. longissima lipidic extract showed an antibacterial activity against several Vibrio species. These results are interesting considering both the resistance against antibiotics developed by vibrios and the need to control fish and shellfish diseases due to vibriosis. Analysis of fatty acid methyl esters performed by gas-chromatography showed that palmitic acid methyl ester (16:0) was the predominant saturated fatty acid (42%), while, among monounsaturated fatty acids, oleic acid methyl ester (18:1) prevailed (8.5%). Because the palmitic acid represents the main component of fatty acids we hypothesized its involvement in the antibacterial activity observed. However, a pure sample of palmitic acid did not show an antibacterial activity. The fatty acid profile of G. longissima revealed also an interesting composition in polyunsaturated fatty acids and in particular the ratio of ω-3 to ω-6 fatty acids was >1 thus suggesting that this macroalga may be used as a natural source of ω3. Moreover, the (1)H NMR spectrum in CDCl(3) of algal lipid fraction shows the characteristic signals of saturated and unsaturated fatty acids as well as other metabolites. Interestingly, in the lipid extract the presence of polyhydroxybutyrate, a linear biodegradable and biocompatible polyester, was clearly identified by NMR spectroscopy. In conclusion, the lipidic extract of G. longissima on account of its antimicrobial activity, nutritional value and content in biodegradable and biocompatible polyester represents an interesting potential biotechnological resource. 相似文献
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Luigi Boitani Iacopo Sinibaldi Fabio Corsi Alessio De Biase Ilaria d’Inzillo Carranza Maria Ravagli Gabriella Reggiani Carlo Rondinini Patrizia Trapanese 《Biodiversity and Conservation》2008,17(3):605-621
The knowledge of the areas inhabited by a species within its distribution range and the connections among patches are critical
pieces of information for successful conservation actions. The internal structure of the extent of occurrence (EO) of a species
is almost always unknown, even for “well-known” flagship species. We developed a methodology to infer the area of occupancy
(AO) within the EO of a species using the limited available data. We present here the results of a three years project funded
by European Union to develop high-resolution models of habitat suitability for 281 medium- to large-sized African mammals
across the whole continent. The existing literature was reviewed and all data on the geographic distribution and environmental
preferences of the selected species were collected. For each species, these data were then expressed in terms of key variables
available as GIS layers at a resolution of 1 km2 over the entire African continent. The AO of each species was obtained merging the information on the ecological needs of
the species and the values of ecological variables over the region identified as EO. The habitat suitability models were evaluated
through direct field work in four countries (Morocco, Cameroon, Uganda, Botswana) chosen as representatives of the environmental
and species diversity of Africa. More than 81% of models had positive true skill statistics (TSS) values, indicating models
performing better than random. Rigorous modeling procedures supported by ad-hoc field evaluation allowed the production of
high-resolution habitat suitability models useful for conservation applications. 相似文献
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Mitochondrial DNA from prehistoric canids highlights relationships between dogs and South-East European wolves 总被引:4,自引:0,他引:4
Verginelli F Capelli C Coia V Musiani M Falchetti M Ottini L Palmirotta R Tagliacozzo A De Grossi Mazzorin I Mariani-Costantini R 《Molecular biology and evolution》2005,22(12):2541-2551
The question of the origins of the dog has been much debated. The dog is descended from the wolf that at the end of the last glaciation (the archaeologically hypothesized period of dog domestication) was one of the most widespread among Holarctic mammals. Scenarios provided by genetic studies range from multiple dog-founding events to a single origin in East Asia. The earliest fossil dogs, dated approximately 17-12,000 radiocarbon ((14)C) years ago (YA), were found in Europe and in the Middle East. Ancient DNA (a-DNA) evidence could contribute to the identification of dog-founder wolf populations. To gain insight into the relationships between ancient European wolves and dogs we analyzed a 262-bp mitochondrial DNA control region fragment retrieved from five prehistoric Italian canids ranging in age from approximately 15,000 to approximately 3,000 (14)C YA. These canids were compared to a worldwide sample of 547 purebred dogs and 341 wolves. The ancient sequences were highly diverse and joined the three major clades of extant dog sequences. Phylogenetic investigations highlighted relationships between the ancient sequences and geographically widespread extant dog matrilines and between the ancient sequences and extant wolf matrilines of mainly East European origin. The results provide a-DNA support for the involvement of European wolves in the origins of the three major dog clades. Genetic data also suggest multiple independent domestication events. East European wolves may still reflect the genetic variation of ancient dog-founder populations. 相似文献
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Luca Peruzzotti-Jametti Joshua D. Bernstock Nunzio Vicario Ana S.H. Costa Chee Keong Kwok Tommaso Leonardi Lee M. Booty Iacopo Bicci Beatrice Balzarotti Giulio Volpe Giulia Mallucci Giulia Manferrari Matteo Donegà Nunzio Iraci Alice Braga John M. Hallenbeck Michael P. Murphy Frank Edenhofer Stefano Pluchino 《Cell Stem Cell》2018,22(3):355-368.e13
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Duccio Panzani Alessandra Rota Paola Marmorini Iacopo Vannozzi Francesco Camillo 《Theriogenology》2014
In this study, 198 donor mares of different breeds, ages, and reproductive category were inseminated with fresh, cooled and frozen or frozen and cooled semen at the embryo transfer station or in private artificial insemination centers during 10 breeding seasons. The results of this activity were retrospectively analyzed by Pearson Chi-square test and logistic regression to evaluate factors affecting multiple ovulations, embryo recovery, embryo quality, and embryo diameter. Out of the 661 cycles, 937 ovulations were recorded (mean ovulations/cycle: 1.42 ± 0.58). Ovulation rate and incidence of multiple ovulations were significantly affected by age, breed, and reproductive category. Uterine flushings for embryo recovery were performed between 7 and 10 days after ovulation and resulted in the recovery of 338 embryos (51.1% embryos/cycle and 36.1% embryos/ovulation, respectively). At least one embryo was recovered in 298 flushings (45.1%). The factors affecting embryo recovery were age, breed, reproductive category, type of semen, number of ovulations, and location of artificial insemination. Flushing protocol and day of flushing had no effect on embryo recovery. Age, type of semen, number of ovulations, and day of flushing had a significant influence on embryo diameter (N = 215). None of the factors included in the model had an effect on embryo quality distribution. 相似文献
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Iacopo Iandelli Andrea Aliverti Bengt Kayser Raffaele Dellacà Stephen J Cala Roberto Duranti Susan Kelly Giorgio Scano Pawel Sliwinski Sheng Yan Peter T Macklem Antonio Pedotti 《Journal of applied physiology》2002,92(5):1943-1952
To understand how externally applied expiratory flow limitation (EFL) leads to impaired exercise performance and dyspnea, we studied six healthy males during control incremental exercise to exhaustion (C) and with EFL at approximately 1. We measured volume at the mouth (Vm), esophageal, gastric and transdiaphragmatic (Pdi) pressures, maximal exercise power (W(max)) and the difference (Delta) in Borg scale ratings of breathlessness between C and EFL exercise. Optoelectronic plethysmography measured chest wall and lung volume (VL). From Campbell diagrams, we measured alveolar (PA) and expiratory muscle (Pmus) pressures, and from Pdi and abdominal motion, an index of diaphragmatic power (W(di)). Four subjects hyperinflated and two did not. EFL limited performance equally to 65% W(max) with Borg = 9-10 in both. At EFL W(max), inspiratory time (TI) was 0.66s +/- 0.08, expiratory time (TE) 2.12 +/- 0.26 s, Pmus approximately 40 cmH2O and DeltaVL-DeltaVm = 488.7 +/- 74.1 ml. From PA and VL, we calculated compressed gas volume (VC) = 163.0 +/- 4.6 ml. The difference, DeltaVL-DeltaVm-VC (estimated blood volume shift) was 326 ml +/- 66 or 7.2 ml/cmH2O PA. The high Pmus and long TE mimicked a Valsalva maneuver from which the short TI did not allow recovery. Multiple stepwise linear regression revealed that the difference between C and EFL Pmus accounted for 70.3% of the variance in DeltaBorg. DeltaW(di) added 12.5%. We conclude that high expiratory pressures cause severe dyspnea and the possibility of adverse circulatory events, both of which would impair exercise performance. 相似文献
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Jonathan J. Petrocelli Alec I. McKenzie Naomi M. M. P. de Hart Paul T. Reidy Ziad S. Mahmassani Alexander R. Keeble Katie L. Kaput Matthew P. Wahl Matthew T. Rondina Robin L. Marcus Corrine K. Welt William L. Holland Katsuhiko Funai Christopher S. Fry Micah J. Drummond 《Aging cell》2023,22(11):e13936
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Rosa A. Cavallo Maria I. Acquaviva Loredana Stabili Ester Cecere Antonella Petrocelli Marcella Narracci 《Central European Journal of Biology》2013,8(7):646-653
In mariculture, diseases of microbial origin can cause significant economic losses worldwide; the evolution of microorganism resistance to antibiotics has resulted in a growing need for new antibacterial compounds that are effective in veterinary medicine and characterized by limited undesirable side effects. Increased attention has recently been turned to seaweeds as a promising source for metabolites with antimicrobial activity. Vibriosis is a common disease, caused by bacteria of the genus Vibrio, that can result in high mortality in aquaculture. The aim of this study was to identify seaweeds with antibacterial activity against some pathogenic Vibrio species, in order to identify a possible alternative to the commonly used antibiotics in aquaculture. Chloroform/methanol lipidic extracts of six seaweed species (Chaetomorpha linum, Cladophora rupestris, Gracilaria dura, Gracilaria gracilis, Gracilariopsis longissima, Ulva prolifera) were tested for their antibacterial activities against six fish pathogenic Vibrio species using the disc diffusion method. Different susceptibilities to lipidic algal extracts were observed. All six of the seaweed extracts tested demonstrated inhibition of Vibrio ordalii. The best was that from Gracilariopsis longissima, showing activity against Vibrio ordalii, Vibrio salmonicida, Vibrio alginolyticus and Vibrio vulnificus. The results confirmed the potential use of seaweed extracts as a source of antibacterial compounds or as a health-promoting feed for aquaculture. 相似文献