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571.
  • 1. The Galapagos Marine Reserve provides refuge for numerous threatened marine species, including 16 mammals, birds, reptiles and fish currently recognized on the 2006 IUCN Red List of Threatened Species, plus an additional 25 endemic fish, mollusc, crustacean, echinoderm, coral and macroalgal species that comply with threatened species criteria because of declining extent of occurrence or highly‐localized ranges, and hence also qualify for inclusion on the Red List.
  • 2. Threatened marine species with restricted ranges are not randomly distributed across the archipelago but tend to co‐occur at a limited number of sites that are predominantly located in the west. Sites at which threatened species are known to persist, particularly those with a large proportion of the global population, are here identified as sites of global conservation significance — key biodiversity areas.
  • 3. The majority (27) of the 38 inshore key biodiversity areas identified are currently protected from fishing because they lie within the 17% of coastal waters that is zoned as ‘no‐take’ tourism or conservation zones. All key biodiversity areas should be protected from extractive exploitation if threatened species are to be safeguarded. This can be achieved, at the minimum, through a relatively minor amendment to the existing marine zoning scheme, whereby an additional 2% of the coastline is dedicated to conservation.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
572.
The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p < 0.05). Increase in grain protein concentration was not only related to total starch concentration (r(2) = -0.80, p < 0.01) but also affected enzymatic hydrolysis of pure starch (r(2) = -0.67, p < 0.01). However, an increase in amylopectin unit chain length between DP 12-18 (F-II) was detrimental to starch concentration (r(2) = 0.46, p < 0.01). Amylose concentration influenced granule size distribution with increased amylose genotypes showing highly reduced volume percentage of very small C-granules (<5 μm diameter) and significantly increased (r(2) = 0.83, p < 0.01) medium sized B granules (5-15 μm diameter). Amylose affected smaller (F-I) and larger (F-III) amylopectin chains in opposite ways. Increased amylose concentration positively influenced the F-III (DP 19-36) fraction of longer DP amylopectin chains (DP 19-36) which was associated with resistant starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p < 0.01) influenced resistant starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 μm) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield.  相似文献   
573.
A rapid and convenient method for the precise quantification of epsilon-(gamma-glutamyl)lysine isopeptide in lyophilized proteolytic digests of cross-linked plant protein samples was developed. The isopeptide was baseline-separated from three other isomers containing lysyl and glutamyl residues by reverse-phase high-performance liquid chromatography after exhaustive proteolytic digestion of the samples cross-linked by a microbial transglutaminase (MTG). Highly selective detection was performed by electrospray mass spectrometry in MS/MS mode. Demonstrating the applicability of the suggested analytical procedure, enzymatic cross-linking of protein isolates from soy [Glycine max (L.) Merr.], pea [Pisum sativum L.], and the sweet lupin species Lupinus albus L. and Lupinus angustifolius L. was investigated after incubation with 0.01 g of MTG/100 g of protein for 0-240 min at 40 degrees C. The liquid chromatography-mass spectrometry (LC-MS) method was successfully applied to monitor the kinetics of epsilon-(gamma-glutamyl)lysine isopeptide formation. Since the calculated initial levels of epsilon-(gamma-glutamyl)lysine in the genuine leguminous protein isolates were between 40 and 77 micromol/100 g, an isopeptide detection limit of 0.5 microg/mL, corresponding to approximately 50 micromol/100 g of protein, was shown to suffice for quantifying the cross-linking rate enzymatically induced by MTG. Concentrations of epsilon-(gamma-glutamyl)lysine in the texturized proteins ranged from 100 to 500 micromol/100 g of protein.  相似文献   
574.
Inhibition of rat mammary tumorigenesis by concord grape juice constituents   总被引:2,自引:0,他引:2  
The effects of Concord grape juice constituents on the promotion of chemically induced rat mammary tumor development and on the proliferation of a rat mammary adenocarcinoma cell line were studied. Isocaloric grape juice formulations provided in the drinking fluid of rats at concentrations of 489 and 651 mg of phenolics/dL of fluid significantly inhibited mammary adenocarcinoma multiplicity compared to controls. Final tumor mass also was significantly decreased for animals provided these two grape juice concentrations compared to controls. In addition, DNA synthesis of the rat mammary adenocarcinoma RBA cell line was significantly inhibited in a dose-dependent manner for cells treated with a grape extract, with an IC50 dose of approximately 14 micrograms of phenolics/mL. This inhibition of DNA synthesis was not accompanied by changes in 8-oxodeoxyguanosine formation or by substantial cell cycle arrest. These studies thus indicate that Concord grape juice constituents can inhibit the promotion stage of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis, in part by suppressing cell proliferation.  相似文献   
575.
The concentrations of Cd, Pb, Fe, Cr, Ni, Se, Sb, As and Cu were investigated in the nesting environment of green turtles in Mediterranean Sea near Kazanl?, Mersin-Turkey. Tissues of plants growing on the beach and the adjacent environment, beach sand, sea ground sediment, sea grass as well as the egg shells from the nests were analyzed and the results showed no significant high levels of heavy metals detected. The higher levels of metals (Cr, Cu, Pb, Cd and As) were found in the samples from ground sea sediments. Ni and Sb were found at higher levels in river waters and Fe was at the highest in field soil. The high levels of Pb, Fe and Cd were also detected in sea grass, and the Cr, Cu and Ni in sea lily when comparison made with other plants. The levels of essential elements such as Fe and Cu were detected as the highest in most of the specimens. The herbivorous green turtles might be affected from the heavy metal concentrations in the future, since they feed on mainly sea grass. The accumulation of heavy metals via rivers into the sea might cause some pollution problems.  相似文献   
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