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1.
The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity. 相似文献
2.
Giovanni Bearzi Elena Politi Stefano Agazzi Sebastiano Bruno Marina Costa Silvia Bonizzoni 《水产资源保护:海洋与淡水生态系统》2005,15(3):243-257
- 1. Boat surveys aimed at studying short‐beaked common dolphins and common bottlenose dolphins in eastern Ionian Sea coastal waters were conducted between 1993 and 2003. During 835 survey days, 24 771 km of total effort was distributed within an area of 480 km2, resulting in 428 common dolphin and 235 bottlenose dolphin sightings.
- 2. Individual photo‐identification was performed extensively throughout this study, making it possible to monitor the number of animals seen in the study area each year and their long‐term residency patterns.
- 3. Common dolphins declined across the study period, from 2.18 encounters/100 km in 1997 to 0.40 encounters/100 km in 2003. In contrast, there was a relatively stable presence of bottlenose dolphins, some individuals showing high levels of site fidelity and others using the area only occasionally.
- 4. The local decline of common dolphins and the low density of bottlenose dolphins appeared to reflect the general status of these cetacean species in the wider Mediterranean region, where common dolphins were classified as endangered in the IUCN Red List in 2003.
- 5. Based on the available evidence, we infer that the present unfavourable status of common dolphins in eastern Ionian Sea coastal waters is largely a consequence of prey depletion.
3.
Trombino S Serini S Di Nicuolo F Celleno L Andò S Picci N Calviello G Palozza P 《Journal of agricultural and food chemistry》2004,52(8):2411-2420
Although an antioxidant mechanism has been involved in the beneficial effects of ferulic acid in human diseases, there are few reports on the antioxidant properties of this compound in isolated membranes and intact cells. Here, we evaluated the ability of ferulic acid in inhibiting lipid peroxidation in rat liver microsomal membranes and reactive oxygen species production in NIH-3T3 fibroblasts, induced by both tert-BOOH and AAPH. We also compared its antioxidant efficiency with that of other antioxidants, such as alpha-tocopherol, beta-carotene, and ascorbic acid, added alone or in combination. Ferulic acid acted as a potent antioxidant in our models, being more effective in protecting from tert-BOOH than from AAPH. Moreover, the compound was the most effective among the antioxidants tested. Synergistic interactions were observed when the compound was used in combination with the other antioxidants, suggesting that they can cooperate in preserving physiological integrity of cells exposed to free radicals. 相似文献
4.
Loredana Zilli Roberta Schiavone Carlo Storelli Sebastiano Vilella 《International Aquatic Research》2012,4(1):1-11
River Gomti, a tributary of river Ganga in northern India, is being polluted due to indiscriminate disposal of domestic sewage and industrial wastes that contain genotoxic chemicals. The study was conducted to evaluate the genotoxic potential of polluted water of river Gomti in two fish species, namely Channa punctatus and Mystus vittatus. The fishes were exposed in situ in nylon cages to the polluted water of river Gomti fixed near a distillery outlet located in Lucknow. The induction of DNA damage and micronuclei were determined in blood erythrocytes using comet assay and micronucleus test, respectively. The induction in micronuclei frequencies and DNA damage were found to be significantly elevated (p?<?0.01) in exposed specimens after 3?days post-exposure as compared to the control, i.e. from laboratory-acclimatized fish specimens. The comparison of DNA damage between the two species indicated that C. punctatus is more sensitive to aquatic pollutants. Thus, this fish could be used as a bio-indicator of genotoxicity for bio-monitoring of water bodies. The results further revealed that the river Gomti is being contaminated with potential genotoxic and mutagenic chemicals produced from industrial and domestic activities; therefore, immediate measures are needed to reduce the inflow of pollutants in the river. 相似文献
5.
F. Faranda A. Salleo G. Lo Paro A. Manganaro 《Aquaculture (Amsterdam, Netherlands)》1984,37(2):125-131
Juvenile Penaeus kerathurus (average weight = 0.64 g) were fed three different daily amounts (40%, 60% and 100% of biomass) of an unprocessed and unsupplemented diet composed of 43% anchovy, 33% shrimp head and 24% squid, whose suitability for P. kerathurus had been previously assessed. The experiment was performed with an animal density of 30/m2 at 23° C for a period of 180 days. From the results obtained, it is concluded that, of the three feeding rates employed, 100% of biomass was suitable for animals weighing 0.64–1.8 g. For animals 1.8–4.3 g a feeding rate of 60% was appropriate, while a reduction to 40% seemed satisfactory for animals over 4.3 g in this experiment. 相似文献
6.
Activity of extracts from wild edible herbs against postharvest fungal diseases of fruit and vegetables 总被引：1，自引：0，他引：1
Maria Antonia Gatto Antonio Ippolito Vito Linsalata Nicholas A. Cascarano Franco Nigro Sebastiano Vanadia Donato Di Venere 《Postharvest Biology and Technology》2011,61(1):72-82
The use of plant extracts could be a useful alternative to synthetic fungicides in the management of rot fungi during postharvest handling of fruit and vegetables. The aim of this study was to assess the in vitro and in vivo activity of extracts obtained from nine wild edible herbaceous species (Borago officinalis, Orobanche crenata, Plantago coronopus, P. lanceolata, Sanguisorba minor, Silene vulgaris, Sonchus asper, Sonchus oleraceus, and Taraxacum officinale) against some important postharvest pathogens, i.e. Botrytis cinerea, Monilinia laxa, Penicillium digitatum, P. expansum, P. italicum, Aspergillus carbonarius, and A. niger. Phenolic composition of all extracts was evaluated by HPLC. Several derivatives of caffeic acid, of the flavones apigenin and luteolin, and of the flavonols kaempferol and quercetin, were identified. Extracts from S. minor and O. crenata showed the highest efficacy in all the trials. In particular, S. minor completely inhibited in vitro the conidial germination of M. laxa, P. digitatum, P. italicum, and A. niger and strongly reduced those of B. cinerea; O. crenata extract showed a lower but still significant reduction of conidial germination on all the tested fungi. Moreover, the extracts from both species were effective in reducing the germ tube elongation also when a slight inhibition of conidial germination was observed. In many cases, a dose effect was observed, with an increase of antifungal activity as the phenolic concentration increased. In trials performed on wounded fruit, S. minor extract completely inhibited brown rot on apricots and nectarines; O. crenata extract strongly reduced grey mould, brown rot, and green mould on table grapes, apricots and nectarines, and oranges, respectively. The inhibition efficacy of extracts was ascribed to the presence of some caffeic acid derivatives and/or flavonoids. HPLC phenolic analyses provided useful information to identify the possible active compounds. 相似文献
7.
Sebastiano Salvidio 《Biological conservation》2009,142(2):455-461
Amphibian populations are declining worldwide and understanding their temporal dynamics should be important to separate declines from natural fluctuations. In this study sixteen long-term amphibian time series, lasting 15 years or more, were analysed by means of conventional methods of time series analysis to evaluate the relative importance of exogenous and endogenous factors controlling population dynamics, and in particular to assess the existence of population cycles. There was significant autocorrelation in seven time series, and the autocorrelation function showed no signs of statistical cyclicity, but in one case there was some evidence for weak periodicity. In 12 populations the partial rate correlation function suggested the presence of direct density dependence, while there was no evidence for delayed density dependent regulation. In all time series the global Lyapunov exponent, a statistic that characterises the predictability of a dynamic system, indicated that the population trajectories had a tendency to converge towards a stable dynamics. These results may have conservation implications, because populations with direct density dependence possess high capacity of returning to equilibrium after a perturbation and therefore are less likely to go extinct. In the future, I encourage ecologists to increase the use of statistical time series methods and autoregressive modelling to analyse amphibian population dynamics in the framework of local and global climate variability. 相似文献
8.
The ion-mediated enhancement of xylem hydraulic conductivity in angiosperms is thought to be controlled by the pectin chemistry of intervessel pit membranes. However, there is little or no direct evidence on the ultrastructure and chemical nature of pit membranes in species that show an 'ionic effect'. The potential link between the magnitude of the ionic effect and pectin composition in intervessel pit membranes of four Lauraceae species (Laurus nobilis, Lindera megaphylla, Litsea sericea and Umbellularia californica) that show rather similar vessel and pit dimensions was studied using transmission electron microscopy (TEM). The TEM observations confirmed the presence of a pectic matrix associated with intervessel pit membranes, indicating that the relative abundance of acidic versus methylesterified pectins was closely related to the ionic effect. The two species examined with a high ionic effect ~20%, i.e. Laurus nobilis and Umbellularia californica) showed relatively high levels of acidic pectins, whereas methylesterified pectins were abundant in Lindera megaphylla and Litsea sericea, which showed a low ionic effect (~10%). Variation in the ionic effect is strongly associated with the chemical nature of pit membrane pectins in the species studied. Our findings support the current interpretation of the ionic effect due to dynamic swelling and shrinking behaviour of pit membrane pectins. 相似文献
9.
Diurnal and seasonal variations in leaf hydraulic conductance in evergreen and deciduous trees 总被引：1，自引：0，他引：1
We studied changes in the hydraulic conductance of leaves (K(leaf)) between dawn and dusk during the growth period (July) and at midday at the beginning of autumn in four tree species. The main objectives of the study were to check the extent of diurnal and seasonal changes in K(leaf) and the relationships between K(leaf), irradiance and leaf gas exchange. Two evergreen (Aleurites moluccana and Persea americana) and two deciduous trees (Platanus orientalis and Quercus rubra) were studied. Leaf hydraulic conductance was measured every 2 h between 0700 and 1900 h in July and compared with values measured between 0900 and 1300 h in October. Other variables measured were photosynthetically active radiation (PAR), leaf conductance to water vapor (gL) and water potential (psiL). In July, K(leaf) varied by up to 75% in Pe. americana on a diurnal basis and by at least 44% in Q. rubra. The diurnal time course of K(leaf) showed a distinct increase between dawn and late morning (1100 h) and a subsequent decrease in the evening in A. moluccana and Pl. orientalis, whereas in the other two species, K(leaf) was highest just after dawn and lowest in the evening. In October, K(leaf) of all the species studied was lower than in July, with differences of 20 to 28% for A. moluccana and Pl. orientalis and of 66 to over 70% in Pe. americana and Q. rubra, respectively. Significant correlations were found between PAR and K(leaf) (in all species) as well as between gL and K(leaf) (in three out of four species). Leaf habit (evergreen or deciduous) did not influence absolute values of K(leaf) or its diurnal variation. 相似文献
10.
Within Europe the question of plant coenosis is attracting growing interest. The quality and quantity of collected information
on forest resources at a global level largely depends on the capacity to collect and analyse data at national and sub-national
scale in a way compatible with those at global or continental levels. In Italy the acceptance of all the international agreements
and protocols on the protection of the environment and management of natural resources, requires a standardization of collected
information and statistics, with the aim to produce homogeneous and integrative data at global level. This need is reflected
in the following points: (1) the adoption of a classification system of land use and forest cover compatible with international
hierarchical systems and definitions; (2) the identification of standard procedures in data collection and data elaboration.
To classify natural resources and, in this case study, forest resources, implies to order natural and semi natural coenosis,
forest and pre-forest communities, in a systematic way, according to the applied variables and to the scale detail. The solution
proposed in this case study is organised according to forest management, through the adoption of the habitat approach, describing
forest and pre-forest types in a synoptic way and performing a system of nomenclature in agreement with the international
standards initiatives. In this way, the characterization of forest types at community level is related to the environmental
planning for the protection of biodiversity. 相似文献