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991.
Phytochemicals and Antioxidant Capacity of Tortillas Obtained after Lime-Cooking Extrusion Process of Whole Pigmented Mexican Maize 总被引:1,自引:1,他引:0
Aguayo-Rojas J Mora-Rochín S Cuevas-Rodríguez EO Serna-Saldivar SO Gutierrez-Uribe JA Reyes-Moreno C Milán-Carrillo J 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(2):178-185
The lime-cooking extrusion represents an alternative technology for manufacturing pre-gelatinized flours for tortillas with the advantages of saving energy and generation of null effluents. The phytochemical profiles (total phenolics, anthocyanins) and antioxidant activity of four different types of whole pigmented Mexican maize [white (WM), yellow (YM), red (RM), blue maize (BM)] processed into tortillas were studied. The lime-cooking extrusion process caused a significant decrease (p?0.05) in total phenolics and antioxidant capacity when compared to raw kernels. Most of the total phenols assayed in raw grains (76.1-84.4 %) were bound. Tortillas from extruded maize flours retained 76.4-87.5 % of total phenolics originally found in raw grains. The BM had the highest anthocyanin content (27.52 mg cyanidin 3-glucoside/100 g DW). The WM, YM, RM and NWM contained 3.3, 3.4, 2.9, and 2.2 %, respectively, of the amount of anthocyanins found in BM. The BM lost 53.5 % of total anthocyanins when processed into extruded tortillas. Approximately 64.7 to 74.5 % of bound phytochemicals from raw kernels were the primary contributors to the ORAC values. Extruded tortillas retained amongst 87.2 to 90.7 % of total hydrophilic antioxidant activity when compared to raw kernels. Compared to the data reported by other authors using the conventional process, the lime-cooking extrusion process allowed the retention of more phenolics and antioxidant compounds in all tortillas. 相似文献
992.
Héctor Manuel Esparza-Leal Wenceslao Valenzuela-Quiñónez Héctor Cabanillas Beltrán José Luis Arredondo Figueroa 《Journal Of Applied Aquaculture》2013,25(4):215-227
The effects of four different ionic composition low salinity water (T1, T2, T3, and T4), on growth and survival of Litopenaeus vannamei marine shrimp juveniles were investigated. Shrimp culture in seawater (Tm) was used as control treatment. The results indicated that there were no significant difference (P < 0.05) in growth, survival, production, and feed conversion ratio (FCR) of L. vannamei juveniles reared in the different treatments, but significant differences (P < 0.05) were observed between each of them when compared with seawater (Tm). After 84 days, culture shrimp grew from 0.02 to 7.58 g in T1. The lowest growth rate was attained in T3 (0.57 g/week), in which potassium and calcium ions concentrations were the lowest (0.58 and 28.00 mg/L, respectively). The recorded survival rate (76.35% to 79.55%) is considered well for the 84 days growout period, although it was 7.6% lower than that recorded in the control treatment. Although there were no significant differences (P < 0.05) in growth with respect to the ionic composition of the four treatments, there was a trend of increasing growth in relation with the ionic ratio found in the seawater (Tm). This aspect should be evaluated more closely in future research. 相似文献
993.
José A. Núñez-Gastélum Dalia I. Sánchez-Machado Jaime López-Cervantes Jesús R. Rodríguez-Núñez Ma. A. Correa-Murrieta Reyna G. Sánchez-Duarte 《Journal Of Aquatic Food Product Technology》2013,22(3):334-343
ABSTRACTThis study focuses on the isolation and quantification of astaxanthin and its esters in the oils extracted from shrimp waste. The content of astaxanthin was determined by high performance liquid chromatography and ranged from 1.5 to 2.1 mg g?1. The astaxanthin and its esters were isolated by thin layer chromatography in three fractions: free astaxanthin, monoester, and diester of astaxanthin, with percentages of 44, 32, and 26%, respectively. Oleic acid was the major fatty acid in the monoester fraction, while palmitic, oleic, and stearic acids were present predominantly in the diester fraction. Free radical-scavenging activity of the oils and the three fractions was evaluated. All oils showed an effect on the decrease in the absorbtion of 1,1-diphenyl-2-picrylhydrazyl solutions, while among the fractions no significant difference occurred. Pigmented oil from shrimp waste is an organic source of pigment and antioxidant astaxanthin, the esters, and fatty acids, such as eicosapentaenoic and docosahexaenoic. 相似文献
994.
Laboratory‐produced juvenile individuals of the species Mytilus chilensis, M. galloprovincialis and their hybrids were subjected to physiological measurements under an experimental diet of Isochrysis galbana (30 × 106 cells L?1), 13°C temperature and a salinity of 30 psu. Pure species individuals showed a higher clearance rate (CR). Mytilus chilensis had a CR of 1.13 L h?1, while M. galloprovincialis registered only 0.78 L h?1. Also, pure taxa registered higher values (above 70%) of absorption efficiency when compared with hybrid individuals. Ammonia excretion in M. chilensis and M. galloprovincialis was 1.5% and 0.4%, respectively, while hybrids registered significantly lower values. Under these experimental conditions, M. chilensis registered the highest scope for growth (P < 0.05), compared with M. galloprovincialis and their hybrids. However, the net growth efficiency index (K 2) in hybridization type I (♀Mg × ♂Mc) was higher (P < 0.05) than other experimental groups. The invasive mytilid M. galloprovincialis showed values that are very similar to those obtained with the hybridization I group (♀Mg × ♂Mc). Finally, we discuss that water temperature is an important factor in the biogeographic separation of both species and the potential effects that the settlement of the invasive species may have for Chilean mussel production. 相似文献
995.
DS Martinez Md Freire P Mazzafera RT Araujo-Júnior RD Bueno ML Macedo 《Journal of insect science (Online)》2012,12(62):1-11
Abstract The objective of this work was to study the insecticidal effect of labramin, a protein that shows lectin-like properties. Labramin was isolated from seeds of the Beach Apricot tree, Labramia bojeri A. DC ex Dubard (Ericales: Sapotaceae), and assessed against the development of the Mediterranean flour moth Ephestia kuehniella Zeller (Lepidoptera: Pyralidae), an important pest of stored products such as corn, wheat, rice, and flour. Results showed that labramin caused 90% larval mortality when incorporated in an artificial diet at a level of 1% (w/w). The presence of 0.25% labramin in the diet affected the larval and pupal developmental periods and the percentage of emerging adults. Treatments resulted in elevated levels of trypsin activity in midgut and fecal materials, indicating that labramin may have affected enzyme-regulatory mechanisms by perturbing peritrophic membranes in the midgut of is. kuehniella larvae. The results of dietary experiments with E. kuehniella larvae showed a reduced efficiency for the conversion of ingested and digested food, and an increase in approximate digestibility and metabolic cost. These findings suggest that labramin may hold promise as a control agent to engineer crop plants for insect resistance. 相似文献
996.
Speranza L Pesce M Patruno A Franceschelli S de Lutiis MA Grilli A Felaco M 《Marine drugs》2012,10(4):890-899
It has been suggested that oxidative stress activates various intracellular signaling pathways leading to secretion of a variety of pro-inflammatory cytokines and chemokines. SHP-1 is a protein tyrosine phosphatase (PTP) which acts as a negative regulator of immune cytokine signaling. However, intracellular hydrogen peroxide (H(2)O(2)), generated endogenously upon stimulation and exogenously from environmental oxidants, has been known to be involved in the process of intracellular signaling through inhibiting various PTPs, including SHP-1. In this study, we investigated the potential role of astaxanthin, an antioxidant marine carotenoid, in re-establishing SHP-1 negative regulation on pro-inflammatory cytokines secretion in U-937 cell line stimulated with oxidative stimulus. ELISA measurement suggested that ASTA treatment (10 μM) reduced pro-inflammatory cytokines secretion (IL-1β, IL-6 and TNF-α) induced through H(2)O(2), (100 μM). Furthermore, this property is elicited by restoration of basal SHP-1 protein expression level and reduced NF-κB (p65) nuclear expression, as showed by western blotting experiments. 相似文献
997.
Renan O. Silva Ana Paula M. Santana Nathalia S. Carvalho Talita S. Bezerra Camila B. Oliveira Samara R. B. Damasceno Luciano S. Chaves Ana Lúcia P. Freitas Pedro M. G. Soares Marcellus H. L. P. Souza André Luiz R. Barbosa Jand-Venes R. Medeiros 《Marine drugs》2012,10(12):2618-2633
Red seaweeds synthesize a great variety of sulfated galactans. Sulfated polysaccharides (PLSs) from seaweed are comprised of substances with pharmaceutical and biomedical potential. The aim of the present study was to evaluate the protective effect of the PLS fraction extracted from the seaweed Gracilaria birdiae in rats with naproxen-induced gastrointestinal damage. Male Wistar rats were pretreated with 0.5% carboxymethylcellulose (control group—vehicle) or PLS (10, 30, and 90 mg/kg, p.o.) twice daily (at 09:00 and 21:00) for 2 days. After 1 h, naproxen (80 mg/kg, p.o.) was administered. The rats were killed on day two, 4 h after naproxen treatment. The stomachs were promptly excised, opened along the greater curvature, and measured using digital calipers. Furthermore, the guts of the animals were removed, and a 5-cm portion of the small intestine (jejunum and ileum) was used for the evaluation of macroscopic scores. Samples of the stomach and the small intestine were used for histological evaluation, morphometric analysis and in assays for glutathione (GSH) levels, malonyldialdehyde (MDA) concentration, and myeloperoxidase (MPO) activity. PLS treatment reduced the macroscopic and microscopic naproxen-induced gastrointestinal damage in a dose-dependent manner. Our results suggest that the PLS fraction has a protective effect against gastrointestinal damage through mechanisms that involve the inhibition of inflammatory cell infiltration and lipid peroxidation. 相似文献
998.
BACKGROUND: A series of 3-benzylfuran-2-yl N,N,N',N'-tetraethyldiamidophosphate derivatives were synthesized as potential new agents to control insects. Their structures were confirmed on the basis of IR, NMR and MS analyses. RESULTS: Ten 3-benzylfuran-2-ylN,N,N',N'-tetraethyl derivatives were prepared from the compound furan-2-yl N' (N,N,N',N'-tetraethyldiamidophosphate). The contact toxicity of all derivatives, at a dose of 10 microg mg(-1) insect, was evaluated against four insect species, Ascia monuste orseis Latr. (Lepidoptera: Pyralidae), Diaphania hyalinata (L.) (Lepidoptera: Pyralidae), Sitophilus zeamais Mots. (Coleoptera: Bruchidae) and Solenopsis saevissima (Smith) (Hymenoptera: Formicidae). The mortality range observed for some derivatives, such as 3-(3-methylbenzyl)furan-2-yl N,N,N',N'-tetraethyldiamidophosphate (82.5% mortality against D. hyalinata; 100% mortality against S. saevissima), was comparable with that of the commercial insecticide chlorpyrifos-methyl. The biological activity of the derivatives depended on the substitution pattern of the benzylic ring. Furan-2-yl N,N,N',N'-tetraethyldiamidophosphate, furan-2-yl N,N-diethylamidochlorophosphate and difuran-2-yl N,N-diethylamidophosphate were also evaluated, displaying, in some cases, activity comparable with that of chlorpyrifos-methyl (90%, 100% and 97.5% respectively against A. monuste orseis). Considerable activity was observed for some furan-2(5H)-ones evaluated. CONCLUSION: Ten 3-benzylfuran-2-yl N,N,N',N'-tetraethyldiamidophosphate derivatives were synthesized and fully characterized from a chemical point of view. The results obtained from the biological assays indicate that this class of compounds can be utilized for the design of new substances endowed with insecticidal activity. 相似文献
999.
Raúl Laiz-Carrión Inês Rosa Viana Juana Rosa Cejas Ignacio Ruiz-Jarabo Salvador Jerez Juan Antonio Martos Almansa Berro Eduardo Juan Miguel Mancera 《Aquaculture International》2012,20(3):585-599
In the present study, the influence of high stocking density and food deprivation on red porgy (Pagrus pagrus L.) energy metabolism was investigated after 14 and 21?days assessing plasmatic, hepatic, and muscular parameters. Specimens were submitted to four different experimental conditions: (1) fed fish under low stocking density (4?kg?m?3, LSD-F); (2) food-deprived fish under low stocking density (LSD-FD); (3) fed fish under high stocking density (50?kg?m?3, HSD-F); and (4) food-deprived fish under high stocking density (HSD-FD). At plasmatic level, cortisol concentration enhanced in fish maintained under HSD condition, with higher effect in fed fish, whereas FD condition decreased values of lactate, protein, and triglycerides. In liver, significant increases in triglyceride levels, together with a decrease in glycogen values, were observed in FD specimens. Furthermore, a weak effect of density in fed fish was observed, with decreasing hepatic glycogen. In white muscle, aminoacid and triglyceride values diminished in FD group, while increased in specimens submitted to HSD condition. Our results suggested an enhancement in P. pagrus gluconeogenic and glycogenolytic potential when submitted to HSD and FD conditions to cope reallocation of metabolic energy due to these different stress situations. 相似文献
1000.
Bruno C. Araújo Renato M. Honji Paulo H. de Mello Renata Guimar?es Moreira 《Aquaculture International》2012,20(6):1161-1181
In addition to the strong influence of the broodstock diet on the development and survival of offspring, domestication may also interfere with the larval life success. We obtained eggs from wild and domesticated Salminus hilarii females and domesticated males. Wild females were caught in the Tiete River and tributaries, and the domesticated females were born three years before the beginning of the experiment in the Ponte Nova Fish Farm. Animals from both groups were fed with the same feed to exclude feed variables. The eggs and larvae were sampled at 0, 8, 16, and 28?h after spawning (HAS), with the last sampling (28 HAS) coinciding with hatching time. After hatching, samplings proceeded at 32, 48, 66, and 96 HAS, with the last sampling (96 HAS) corresponding to the end of yolk sac consumption. Finally, the last experimental period was during the larvae exogenous feeding phase, at 102, 118, 166, and 214 HAS. Our data revealed that domestication of S. hilarii females influenced fatty acid (FA) metabolism during embryo and larva development. However, the structure of membrane phospholipid FA remained mostly stable, with changes principally in the neutral fraction. When the external conditions, mainly water and feed quality, remained constant, domestication of S. hilarii females did not significantly affect the structural FA composition but influenced the selectivity of consumption and/or storage of specific FA. 相似文献