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161.
- This study aimed to determine biological and distributional aspects of deep-sea giant isopods Bathynomus giganteus and Bathynomus miyarei to assess their extinction risk.
- Bathynomus giganteus (663 specimens) and B. miyarei (649 specimens) were collected during five research cruises involving 265 h of sampling effort during 32 fishing operations of circular pots, baited traps, ranging from 400 and 1,000 m deep, between 26 and 29°S adjacent to the Brazilian coast.
- A trend towards larger, sexually mature animals in shallower regions was observed for both species, and depth was the most important environmental variable influencing the animals’ distribution.
- Bathynomus giganteus were collected between 600 m and 1,000 m depth, while the highest densities of B. miyarei were at shallower depths, between 400 and 600 m.
- The sex ratio was equal for both B. giganteus and B. miyarei for different seasons, latitudes and bathymetries.
- The sexual maturity of B. giganteus was estimated at 340–345 mm total length for males and between 280–290 mm for females. Bathynomus miyarei males’ sexual maturity was estimated in the 225–230 mm size class.
- Bathynomus giganteus showed reproductive activity throughout the year.
- The longevity of B. giganteus was estimated at 6 years for males and 7.7 years for females. The longevity of B. miyarei was estimated at 9 years for males and 6 years for females.
- Extinction risk assessment for B. giganteus, which has a greater latitudinal and bathymetric distribution, was evaluated as Least Concern. However, B. miyarei was evaluated in the Data Deficient category.
162.
163.
Martín-Cabrejas MA Sanfiz B Vidal A Mollá E Esteban R López-Andréu FJ 《Journal of agricultural and food chemistry》2004,52(2):261-266
The effect of fermentation on antinutritional factors and also on total dietary fiber (TDF), insoluble (IDF) and soluble (SDF) dietary fiber fractions was studied in beans (Phaseolus vulgaris L.). The processes studied were two types of fermentation (lactic acid and natural), and a portion of the obtained flours were processed by autoclaving. The dietary fiber (DF) content and its components were determined using the enzymatic-gravimetric and enzymatic-chemical methods. The TDF content ranged from 24.5% dry matter (DM) in the raw to 25.2% DM in the processed beans. All the processing treatments significantly decreased the SDF content, and irrelevant changes were noticed in the IDF content of processed beans. Cellulose content of all samples was reduced by the processing treatments. Correspondingly, higher amounts of resistant starch was observed in the processed beans, except in the lactic acid fermented ones. However, the levels of pectic polysaccharides and Klason lignin were higher in the samples fermented by Lactobacillus plantarum. The action of microorganisms was determinant for the different degradation of the bean cell wall, disrupting the protein-carbohydrate integration, thus reducing the solubility of DF. 相似文献
164.
Polyphenolic profiles of Basque cider apple cultivars and their technological properties 总被引:3,自引:0,他引:3
Alonso-Salces RM Barranco A Abad B Berrueta LA Gallo B Vicente F 《Journal of agricultural and food chemistry》2004,52(10):2938-2952
The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis. Total polyphenols are distributed in a wide concentration range depending on the cultivar. Procyanidins are the class of polyphenols that present major concentrations in apple. Their average degrees of polymerization range from 4 to 8 depending on the cultivar. Apple cultivars were technologically classified into bitter and nonbitter categories using different classification systems obtained by applying several pattern recognition techniques, such as principal component analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed-forward-artificial neural networks, to apple pulp, peel, or juice data (individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins). Bitter apple cultivars present higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Detailed knowledge of the polyphenolic profile of each apple cultivar affords information about their susceptibility to oxidation, their sensory properties (bitterness, astringency), and their possible influence on the characteristics and quality of the final product (juice, cider) when apples are processed. 相似文献
165.
Albero B Sánchez-Brunete C Tadeo JL 《Journal of agricultural and food chemistry》2004,52(19):5828-5835
An analytical method for the simultaneous determination of 51 pesticides in commercial honeys was developed. Honey (10 g) was dissolved in water/methanol (70:30; 10 mL) and transferred to a C(18) column (1 g) preconditioned with acetonitrile and water. Pesticides were subsequently eluted with a hexane/ethyl acetate mixture (50:50) and determined by gas chromatography with electron impact mass spectrometric detection in the selected ion monitoring mode (GC-MS-SIM). Spiked blank samples were used as standards to counteract the matrix effect observed in the chromatographic determination. Pesticides were confirmed by their retention times, their qualifier and target ions, and their qualifier/target abundance ratios. Recovery studies were performed at 0.1, 0.05, and 0.025 microg/g fortification levels for each pesticide, and the recoveries obtained were >86% with relative standard deviations of <10%. Good resolution of the pesticide mixture was achieved in approximately 41 min. The detection limits of the method ranged from 0.1 to 6.1 microg/kg for the different pesticides studied. The developed method is linear over the range assayed, 25-200 microg/L, with determination coefficients of >0.996. The proposed method was applied to the analysis of pesticides in honey samples, and low levels of a few pesticides (dichlofluanid, ethalfluralin, and triallate) were detected in some samples. 相似文献
166.
Amaral JS Cunha SC Alves MR Pereira JA Seabra RM Oliveira BP 《Journal of agricultural and food chemistry》2004,52(26):7964-7969
A total of 26 walnut (Juglans regia L.) samples from 9 cultivars (Arco, Franquette, Hartley, Lara, Marbot, Mayette, Mellanaise, Parisienne, and Rego) harvested in the 2001, 2002, and 2003 crop years and grown in two geographical origins (Braganca and Coimbra, Portugal) were evaluated with regard to their triacylglycerol composition. The methodology employed was reversed-phase high-performance liquid chromatography coupled to an evaporative light-scattering detector (RP-HPLC-ELSD) after extraction of the lipidic fraction of the nuts. Nine compounds were separated, identified, and quantified. All samples presented an identical qualitative profile composed by LLnLn, LLLn, LLL, OLLn, OLL, PLL, OOL, and PLO (P = palmitoyl; O = oleoyl; L = linoleoyl; Ln = linonenoyl). Trilinolein (LLL) was the major triglyceride, followed by dilinoeoyl-oleoyl-glycerol (OLL) and dilinoleoyl-linolenoyl-glycerol (LLLn), with mean values of 37.7, 18.5, and 18.4%, respectively. Significant differences in composition were found between cultivars, and these differences were also significant when cultivars were grouped by year of production, showing that besides genetic factors, the triacylglycerol composition can be strongly influenced by environmental factors. 相似文献
167.
168.
Ferreira SR de Araújo JV Braga FR Araujo JM Frassy LN Ferreira AS 《Veterinary research communications》2011,35(8):553-558
Ascaris suum is a gastrointestinal nematode parasite of swines. The aim of this study was to observe Pochonia chlamydosporia fungus on biological control of A. suum eggs after fungus passage through swines gastrointestinal tract. Eighteen pigs, previously dewormed, were randomly divided
into three groups: group 1, treated with the fungus isolate VC4; group 2, treated with the fungus isolate VC1 and group 3
did not receive fungus (control). In the treated groups, each animal received a 9 g single dose of mycelium mass containing
P. chlamydosporia (VC1 or VC4). Thereafter, animal fecal samples were collected at the following intervals: 8, 12, 24, 36, 48, 72 and 96 h
after treatment beginning and these were poured in Petri dishes containing 2% water-agar culture medium. Then, 1,000 A. suum eggs were poured into each dish and kept in an incubator at 26°C and in the dark for 30 days. After this period, approximately
100 eggs were removed from each Petri dish and morphologically analyzed under light microscopy following the ovicidal activity
parameters. The higher percentage observed for isolated VC4 eggs destruction was 57.5% (36 h) after fungus administration
and for isolate VC1 this percentage was 45.8% (24 h and 72 h) (p > 0.01). P. chlamydosporia remained viable after passing through the gastrointestinal tract of swines, maintaining its ability of destroying A. suum eggs. 相似文献
169.
Montaño-Leyva B Rodriguez-Felix F Torres-Chávez P Ramirez-Wong B López-Cervantes J Sanchez-Machado D 《Journal of agricultural and food chemistry》2011,59(3):870-875
Cellulose nanofibers from durum wheat straw ( Triticum durum ) were produced and characterized to study their potential as reinforcement fibers in biocomposites. Cellulose was isolated from wheat straw by chemical treatment. Nanofibers were produced via an electrospinning method using trifluoroacetic acid (TFA) as the solvent. The nanofibers were 270 ± 97 nm in diameter. Analysis of the FT-IR spectra demonstrated that the chemical treatment of the wheat straw removed hemicellulose and lignin. XRD revealed that the crystallinity of the cellulose was reduced after electrospinning, but nanofibers remained highly crystalline. The glass transition temperature (T(g) value) of the fibers was 130 °C, higher than that of cellulose (122 °C), and the degradation temperature of the fibers was 236 °C. Residual TFA was not present in the nanofibers as assessed by the FT-IR technique. 相似文献
170.