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21.
Knowledge about the effects of captivity and environmental stress on fish populations is basic to culture them for ornamental, conservation or exploitation purposes. The aim of this study was to test how captivity affect morphological development of bilateral characters and whether levels of fluctuating asymmetry, morphological abnormalities and ectoparasites reflect developmental stress caused by adverse environmental conditions in two species of cyprinids, goldfish Carassius auratus and two varieties of carp Cyprinus carpio, scale and mirror carp. Samples from captivity were caught in an artificial pond (Madrid City, Spain), which presents poor environmental conditions; while samples from nature were captured in the Ebro River basin (NE Spain). Six meristic and four morphometric bilateral characters were measured and compared between the two samples. Additionally, the incidence of morphological abnormalities and ectoparasites was also recorded. Captive goldfish presented significant lower number of scales of the lateral line, scale rows above lateral line and length of pectoral and ventral fins. Captive carps showed significant shorter first barbels and longer ventral fins. Ornamental goldfish showed significant higher levels of fluctuating asymmetry than wild samples for number of branched rays of pectoral fin, lateral line, scale rows below lateral line and length of pectoral and ventral fins. Ornamental carps presented a similar trend for the same characters, except for branched rays and length of pectoral fins, together with the length of second barbels. In the artificial pond, the incidence of abnormalities was higher in carp, whereas goldfish showed a higher occurrence of ectoparasites. These facts support the hypothesis of a different species response to environmental stress. The overall results indicate that fish from the artificial pond are subjected to environmental stress caused by adverse conditions such as overcrowding and lower water quality. Moreover, estimated parameters in this study mean a useful tool to detect developmental instability in confined fish.  相似文献   
22.
The effect of claw ablation on the growth and survival of juvenile Macrobrachium rosenbergii was tested; two sets of controls were used consisting of a group of intact prawns, and an additional group whose first pair of walking legs had been ablated so as to serve as controls for injury and regeneration. Survival among claw-ablated prawns was twice as high as that for the two control groups. Intact prawns weighed more than those with ablated appendages. During the experiment the coefficient of variation of mean weight decreased in the claw-ablated group. It increased in the intact prawns and was relatively stable in the group with ablated first pair of walking legs. The biomass of the claw-ablated group doubled within the test period while that of the controls was stable because the gain in mean weight and the mortalities counterbalanced each other.  相似文献   
23.
The effects of enzymatic deamidation by protein-glutaminase (PG) on the functional properties of soy protein isolate (SPI) were studied. Conditions for the deamidation were evaluated by means of response surface methodology (RSM). Optimal conditions based on achieving a high degree of deamidation (DD) with a concurrently low degree of hydrolysis (DH) were 44 °C, enzyme:substrate ratio (E/S) of 40 U/g protein and pH 7.0. Under optimal conditions, both DD and DH increased over time. SDS-PAGE results indicated that lower molecular mass subunits were produced with increasing DD. Far-UV circular dichroism spectra revealed that the α-helix structure decreased with higher DD, while the β-sheet structure increased until 15 min of deamidation (32.9% DD), but then decreased at higher DD. The solubility of deamidated SPI was enhanced under both acidic and neutral conditions. SPI with higher DD showed better emulsifying properties and greater foaming capacity than SPI, while foaming stability was decreased. It is possible to modify and potentially improve the functional properties of SPI by enzymatic deamidation using PG.  相似文献   
24.
The common bean contains phytochemicals, including phenolic compounds, which can provide health benefits to the consumer. Our objective was to characterize the polyphenolic compounds present in the seed coat of Black Jamapa bean and to test fractionation methods that permit the recovery of polyphenolics in their naturally occurring forms. A 100% methanol extract from seed coats was subjected to different chromatographic fractionation methods. Analysis by HPLC-MS revealed that a better separation of phytochemicals was achieved using direct silica gel fractionation, which allowed more accurate identification of compounds, especially of the flavonols. Anthocyanins, flavanol monomers, and heterogeneous flavanol oligomers up to hexamers were detected. To our knowledge, this is the first time that myricetin glycoside and proanthocyanidin oligomers containing (epi)-gallocatechin have been reported in the black bean. The fractionation methods used in this study produced large quantities of natural mixtures of flavonoids suitable for testing bioactivity and phytochemical interactions.  相似文献   
25.
Lunasin is a unique and novel cancer preventive peptide originally isolated from soy. Information on lunasin concentration of soybean cultivars and commercial soy proteins would be useful in developing lunasin-enriched cultivars and soy products. We report the development of an enzyme-linked immunosorbent assay (ELISA) method to identify lunasin and quantify the variations in concentration in 144 selected, diverse soybean accessions from the U.S. Department of Agriculture Soybean Germplasm Collection, several commercially available soy protein fractions and isoflavone-enriched products. With synthetic lunasin and monoclonal antibody, ELISA shows a linear concentration range of 24-72 ng/mL, good reproducibility, a detection limit of 8 ng/mL, and a recovery of 90% on spiked soy samples. Lunasin concentrations in the tested materials range from 0.10 to 1.33 g/100 g flour. Differences that exceeded 100% have been observed among accessions of similar maturity that were grown in the same environment, indicating that genetic differences in soybeans exist for lunasin. The mean of 23 major ancestral lines of U.S. cultivars is similar to the mean of 16 modern cultivars selected to represent the current diversity of the crop, but the highest values were found within the ancestral and exotic accessions. Soy protein concentrate, isolate, and hydrolyzate contain 2.81 +/- 0.30, 3.75 +/- 0.43, and 4.43 +/- 0.59 g lunasin/100 g flour, respectively, while soy flour and soy flakes contain 1.24 +/- 0.22 g lunasin/100 g flour. Isoflavone-enriched products contain very little or no lunasin. The relative mass (M(r)) of lunasin in the samples is 5.45 +/- 0.25 kDa. The wide range of lunasin concentrations within the Glycine max species indicates that the levels of this important bioactive peptide can be genetically manipulated. Furthermore, soy isolates and hydrolyzed soy proteins contain the highest concentrations of lunasin.  相似文献   
26.
Trypsin inhibitors (TI), tannins, and lectins appear to have a role in preventing chronic diseases in humans. The genetic variability of these traits in common bean needs to be ascertained in order to increase levels through breeding. The variability of TI, tannin, and lectins was determined in five bean cultivars grown at five locations in Mexico. TI and tannins contents in colored beans that belong to the Jalisco race were higher (11.1-11.9 trypsin units inhibited (TUI)/mg and 29.0-38.1 mg catechin equivalent (CE)/g, respectively) than cultivars of the Durango race (7.9-8.3 TUI/mg and 16.8-19.9 CE/mg, respectively). Bayo Victoria, a Durango race cultivar, had three times more lectins than levels reported for soybean. Cultivar influenced TI and tannins contents (p < 0.001), whereas site affected lectins (p < 0.001). An increase in levels of TI and tannins could be enhanced through breeding.  相似文献   
27.
The behavior of volatile compounds according to two enzymatic treatments applied during the manufacture of fruit juice is described. More than 80 compounds were detected of a wide range of chemical families (alcohols, aldehydes, ketones, terpenoids, esters, norisoprenoids, ...). Theaspirane and alpha-isophoron were tentatively identified for the first time in apricot and peach fruits. The enzymes used, for extraction or clarification of fruit juices, modified the polysaccharides separated by molecular weight and the content of soluble polysaccharides. This could indicate differences in the fruit juice matrix, which could be related to observed changes in the volatile profile. In apricot, the enzymes enhanced the juice in terpenes and norisoprenoids as varietal compounds. In peach and pear, the enzymes used did not favor the amount of lactones and decadienoate esters, the character impact compounds, respectively.  相似文献   
28.
A HS-SPME method coupled to GC-MS was developed and applied for the qualitative and semiquantitative characterization of distilled gin volatile fraction. Sampling, chromatographic conditions, and method performances were evaluated, and the developed method was applied as a comparative study of some of the most popular commercial London Dry Gins and other gins with geographic denominations. During this study, 70 components of the gins' volatile fraction were isolated, tentatively identified or identified by reference compounds. They were mainly represented by mono- and sesquiterpenic compounds, which were quantitatively determined. The comparative study of London Dry Gins and gins with geographical indication permitted clear differentiation between the gins with geographical indication and one of the London Dry Gins tested.  相似文献   
29.
The influence of fatty acids (free and bound as ethyl esters) on wine foaming was studied in different white wines and the corresponding sparkling wines. Moreover, from three of these wines the foam formed by CO(2) injection was separated, and two fractions were then obtained: foam wine (FW) and remainder wine (RW). In these fractions and the sparkling wines produced from them, foam properties and fatty acids were also determined. The free fatty acids C8, C10, and C12 were negatively correlated with foamability (HM), whereas the ethyl esters of hexanoic, octanoic, and decanoic acids were positively related to HM. The value of HM was directly proportional to the ratio of esterified to unesterified fatty acids. This was confirmed by the changes that occur in the esterification ratio during the second fermentation and aging. No influence was observed on either the Bikerman coefficient or the stability time of foam.  相似文献   
30.
Forty-one samples of apples (peel plus pulp), obtained from eight cultivars, were examined for concentration of some important phytochemicals and for antioxidant activity expressed as peroxyl radical trapping efficiency. Five major polyphenolic groups plus ascorbate were identified and quantified by HPLC in the apple varieties. Oligomeric and polymeric proanthocyanidins were found to be about two-thirds of total polyphenols. The antioxidant efficiency of the apple extracts and of representative pure compounds for each group of phytochemicals was measured in a micellar system mimicking lipid peroxidation in human plasma. Although the amount of polyphenols measured by HPLC is similar to that measured by standard methods, the antioxidant efficiency calculated on the basis of the contribution of the pure compounds was lower than the antioxidant efficiency of the apple extracts. The higher efficiency of apples appears to be strictly related to the overwhelming presence of oligomeric proanthocyanidins.  相似文献   
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