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111.
Shonouda M Angeli S Schutz S Vidal S 《Pakistan journal of biological sciences: PJBS》2008,11(9):1246-1251
Flowers of Ziziphus spina christi are known to be attractive for parasitoids and predators. In Y-tube olfactometer experiments, the dried flowers attracted significantly (p < 0.001) the female parasitoids Aphelinus abdominalis. The flower volatile compounds were analyzed to understand which compounds could be specifically responsible for this attractiveness. The volatile compounds of Ziziphus flowers were extracted by closed-loop-stripping-analysis (CLSA) and also by solid phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis. The main chemical classes of the volatile compounds are aldehydes, monoterpene-alcohols, ketones and hydrocarbons. Flower extract and some specific compounds will be further tested for their responsiveness to predators and parasitoids in behavioural and electrophysiological experiments. 相似文献
112.
Evaluation of the Lime-Cooking and Tortilla Making Properties of Quality Protein Maize Hybrids Grown in Mexico 总被引:1,自引:0,他引:1
Serna-Saldivar SO Amaya Guerra CA Herrera Macias P Melesio Cuellar JL Preciado Ortiz RE Terron Ibarra AD Vazquez Carrillo G 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(3):119-125
Eleven experimental and three commercial white quality protein maize (QPM) hybrids and two regular endosperm controls were planted at Celaya, Guanajuato, Mexico with the aim of comparing grain physical characteristics, protein quality, lime-cooking and tortilla making properties. All genotypes were planted under irrigation using a density of 80,000 plants/ha and fertilized with 250 kg N-60 P-60 K per hectare. When compared with the controls these QPM genotypes had lower test (77.4 vs. 76.5 kg/hL) and 1,000 kernel weights (327 vs. 307 g), softer endosperm texture (2.5 vs. 1.8 where 1 = soft, 2 intermediate and 3 hard endosperm), lower protein (10.0 vs. 8.0%), higher nixtamal water uptake after 30 min lime-cooking (50.0 vs. 53.1% moisture) and lower pericarp removal scores. The lower thousand-kernel weight and softer endosperm texture observed in the QPM genotypes lowered the optimum lime-cooking time as estimated with regression equations. Most QPM genotypes had higher amounts of lysine, tryptophan and albumins/globulins when compared with the controls. QPMs HEC 424973, HEC 774986 and HEC 734286 had the best grain traits for nixtamalization and therefore the best potential for industrial utilization. The commercial use of these QPM hybrids should benefit Mexicans who depend on tortillas as the main staple. 相似文献
113.
The antiproliferative activity of fresh fruit juices extracted from Citrus sinensis (cv. Washington Navel and cv. Sanguinello), C. deliciosa cv. Avana, C. clementina cv. Nules, C. aurantium subsp. myrtifolia , was evaluated against K562 (human chronic myelogenous leukemia), HL-60 (human leukemia) and MCF-7 (human breast adenocarcinoma) cell lines. All the juices tested showed antiproliferative activity. Moreover, the pattern of the main flavanone compounds in the juices has been determined by HPLC analysis. 相似文献
114.
David Del Pozo-Insfran Sergio O. Serna Saldivar Carmen H. Brenes Stephen T. Talcott 《Cereal Chemistry》2007,84(2):162-168
White and blue corns of Mexican and American origins were lime-cooked to obtain nixtamals with optimal moisture (48–50%) for tortillas and chips. Blue kernels had less bulk density, softer endosperm and, consequently, required less cooking time than the white kernels. The optimum cooking regime for the white kernels was 100°C for 20 min, while the optimum for both pigmented genotypes was 90°C for 0 min (until the lime-cooking solution reached 90°C). Doughs, tortillas, and chips were characterized by total soluble phenolics (TSP), anthocyanins (ACN), and antioxidant capacity (AOX). A dough acidification procedure using fumaric acid (pH 5.2) was assessed as a means to improve TSP, ACN, and AOX retention. The Mexican blue corn had higher AOX (16%) than the American blue genotype, although the latter had a threefold higher TSP content (12.1 g/kg, dwb). Mexican and American blue corns had higher AOX capacity (29.6 and 25.6 μM trolox equivalents [TE]/g dwb), respectively, than the white corn (17.4 μM TE/g). White corns did not have detectable amounts of ACN, while blue Mexican and American kernels contained 342 and 261 mg/kg. Lime cooking had the greatest negative impact on the stability of TSP, ACN, and AOX. However, the acidification reduced ACN, TSP, and AOX losses by 8–23, 3–14, and 4–15%, respectively. Similar ACN losses were observed for both types of blue kernels when processed into nixtamal/dough (47%); however, ACN losses in tortillas and chips manufactured from the American blue genotype were higher (63 and 81%, respectively) than those of Mexican blue corn products (54 and 75%). ACN losses were highly correlated to TSP (r = 0.91) and AOX capacity losses (r = 0.94). 相似文献
115.
116.
Maria Eugenia Caceres Fulvio Pupilli Efisio Piano Sergio Arcioni 《Genetic Resources and Crop Evolution》2000,47(4):455-459
The potential use of RFLP molecular markers for the identification of four creeping bentgrass (Agrostis stolonifera L.) cultivars and one variety of A. tenuis Sibth. used as control, was investigated. Seven probes out of the total 44 screened were able to differentiate all five cultivars at once. On the basis of their genetic similarity the varieties bred at the Pennsylvania State University were grouped closely together, whereas the variety Prominent and the A. tenuis control were more distantly related. 相似文献
117.
Leotta GA Deza N Origlia J Toma C Chinen I Miliwebsky E Iyoda S Sosa-Estani S Rivas M 《Veterinary microbiology》2006,118(1-2):151-157
Shiga toxin producing-Escherichia coli (STEC) is an important emerging pathogen, and ruminants are recognized as their main natural reservoir. The aim of this work was to establish the frequency of STEC in non-domestic mammals of the Zoo and Botanical Garden of La Plata City, Argentina, and to pheno-genotypically characterize STEC isolates. By polymerase chain reaction (PCR), Shiga toxin (stx) gene sequences were detected in 50.8% of 65 fecal samples. Twenty-five STEC strains were isolated from 38.5% of the Zoo's animals. Ten species of order Cetartiodactyla and one species of order Rodentia were recognized as new STEC carriers. STEC strains belonged to 7 different serotypes including new serotypes O12:H25 and O13:H6. Serotype O146:H28, previously associated with human infections, represented 24% of STEC isolates. The most frequent Shiga toxin identified were type 1c and type 2c. Nineteen strains were positive for iha gene, 8 strains were positive for ehxA gene. Moreover, all strains were positive for lpfAO113 and negative for rfbO157, eae, saa, lpfAO157/OI-141, lpfAO157/OI-154, efa1, and toxB genes. Results obtained by XbaI-pulsed-field gel electrophoresis (XbaI-PFGE) confirmed the transmission of STEC strains among different animal species and suborders. In addition, we observed a potential association between STEC-harboring animal and factors such as belonging to order Cetartiodactyla, living in a pit, and belonging to a non-autochthonous species. This is the first work developed with zoological mammals and STEC in Argentina. 相似文献
118.
119.
Effects of exposure to artificial long days on milk yield,maternal insulin‐like growth factor 1 levels and kid growth rate in subtropical goats
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Horacio Hernández José Alfredo Flores José Alberto Delgadillo Ilda G. Fernández Manuel de Jesús Flores Ángel Mejía José Manuel Elizundia Marie Bedos José Luis Ponce Sergio Ramírez 《Animal Science Journal》2016,87(4):484-491
This study was designed to determine whether any relationship exists between exposure to artificial long days, milk yield, maternal plasma insulin‐like growth factor 1 (IGF‐1) levels, and kid growth rate in goats. One group of lactating goats was maintained under naturally decreasing day length (control group; n = 19), while in another one, they were kept under artificial long days (LD group; n = 19). Milk yield was higher in goats from the LD group than that in the control group (P < 0.05). Maternal IGF‐1 levels at day 57 of lactation were higher (P < 0.05) in goats from the LD group than the levels in the control group and were positively correlated with the total milk yields per goat at days 43 and 57 of lactation (r = 0.77 and r = 0.84, respectively; P < 0.01). Daily weight gain at week 4 was higher (P < 0.01) in kids from the LD group than that in kids from the control group and was correlated with total and average IGF‐1 maternal levels (r = 0.60 and r = 0.60, P < 0.05). It was concluded that submitting lactating goats to artificial long days increases milk yield, plasma IGF‐1 maternal levels and the growth rate of the kids. 相似文献
120.
Lipid droplet distribution of immature canine oocytes in relation to their size and the reproductive stage
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Federica Ariu Alessandro Strina Ombretta Murrone Laura Falchi Daniela Bebbere Sergio Ledda Maria Teresa Zedda Salvatore Pau Luisa Bogliolo 《Animal Science Journal》2016,87(1):147-150
This study investigated the distribution of lipid droplets (LD) in immature canine oocytes in relation to their size and the reproductive stage. Oocytes were collected from the ovaries of bitches at different estrous stages, divided according to their size (110‐120 µm; >120 µm), and stained with Nile Red to detect lipid droplet distribution. At the follicular phase most of the oocytes displayed a diffuse pattern of LD distribution, whereas at anestrus and luteal phase oocytes showed LD mainly in a peripheral/ perinuclear LD distribution. A significantly higher intensity of LD has been recorded in the oocytes > 120 µm compared to those of smaller size (110 ‐ 120 µm) at all stages of the estrous cycle. At follicular phase, oocytes > 120 µm displayed LD intensity similar to that of oocytes > 120 µm at luteal phase and higher compared to the oocytes of the other groups. 相似文献