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51.
Total flavonoid content (TFC) and cyanidin‐3‐glucoside (Cyd‐3‐glu) of seed and seed coat extract of 16 genotypes from five species of Carthamus were studied, and their major polyphenolic compounds and antioxidant activity of the seed coat extracts were determined using HPLC analysis and DPPH assay, respectively. Additionally, fatty acids composition of the seed oil was analyzed by GC. In general, TFC and Cyd‐3‐glu content of seed coat extracts were higher than those of seed extracts. A novel breeding line with black seed coat (named A82) depicted lower TFC (3.79 mg QUE/g DW) but higher Cyd‐3‐glu (24.64 mg/g DW) compared to the white and other seed‐pigmented genotypes. DPPH radical scavenging activity showed a strong association with Cyd‐3‐glu content (r = 0.84), but no correlation with TFC (r = ?0.32). HPLC analysis of seed coat extracts revealed that four compounds were dominant constituents including rutin (7.23 – 117.95 mg/100 g DW), apigenin (4.37 – 64.88 mg/100 g DW), quercetin (3.09 – 14.10 mg/100 g DW), and ferulic acid (4.49 – 30.41 mg/100 g DW). Interestingly, the genotype A82 with an appropriate polyunsaturated/saturated fatty acids index (5.46%) and a moderate linoleic fatty acid content (64.70%) had higher nutritional and pharmaceutical value than all the other genotypes. 相似文献
52.
Jérôme M. W. Gippet Florence Piola Soraya Rouifed Marie-Rose Viricel Sara Puijalon Christophe J. Douady Bernard Kaufmann 《Arthropod-Plant Interactions》2018,12(3):351-360
Urbanized landscapes are the theater of multiple simultaneous biological invasions likely to affect spread dynamics when co-occurring introduced species interact with each other. Interactions between widespread invaders call for particular attention because they are likely to be common and because non-additive outcomes of such associations might induce negative consequences (e.g., enhanced population growth increasing impacts or resistance to control). We explored the invasions of two widespread invasive taxa: the Japanese knotweed species complex Fallopia spp. and the invasive garden ant Lasius neglectus, in the urban area of Lyon (France). First, we investigated landscape habitat preferences as well as co-occurrence rates of the two species. We showed that Fallopia spp. and L. neglectus had broadly overlapping environmental preferences (measured by seven landscape variables), but their landscape co-occurrence pattern was random, indicating independent spread and non-obligatory association. Second, as Fallopia spp. produce extra-floral nectar, we estimated the amount of nectar L. neglectus used under field conditions without ant competitors. We estimated that L. neglectus collected 150–321 kg of nectar in the month of April (when nectar production is peaking) in a 1162 m2 knotweed patch, an amount likely to boost ant population growth. Finally, at six patches of Fallopia spp. surveyed, herbivory levels were low (1–6% loss of leaf surface area) but no relationship between ant abundance (native and invasive) and loss of leaf surface was found. Co-occurrences of Fallopia spp. and L. neglectus are likely to become more common as both taxa colonize landscapes, which could favor the spread and invasion success of the invasive ant. 相似文献
53.
Multiple Cbfa/AML sites in the rat osteocalcin promoter are required for basal and vitamin D-responsive transcription and contribute to chromatin organization. 总被引:9,自引:0,他引:9
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54.
Dallal Chergui Soraya Akretche-Kelfat Lynda Lamoudi Mamoon Al-Rshaidat Farida Boudjelal Hamid Ait-Amar 《Saudi Journal of Biological Sciences》2021,28(12):7134-7141
In the present work, the GHARS and the MECH DEGLA downgraded date varieties were used in a fermentation medium in order to produce citric acid by the Aspergillus niger. The biochemical characteristics of the dates were investigated, along with the chemical and physical characteristics of the solutions of both samples. The analyzed parameters included the moisture and sugar content, the ash residual, the pH values, and the electrical conductivity. The effect of the following fermentation parameters was studied: initial pH, temperature, incubation period, and methanol. For the GHARS and MECH DEGLA date varieties respectively, the ash residual measured at 1.90% and 2.47%. For each date variety, the moisture and total sugars were measured at 11.59% and 85%, for the GHARS, and 12.82% and 80.47% for the MECH DEGLA. Citric acid production using either of the two varieties of dates showed a high yield in a short time.The obtained results showed that the highest production of citric acid by both medium of dates was achieved at the initial pH value of 3.0, temperature 30 °C, and an incubation period of 8 days. Also, the maximum amount of citric acid was produced when both mediums contained 4% of methanol. Both varieties of dates showed a good yield for the citric acid and can be used as a culture medium since they are economic and ensure good growth for the Aspergillus niger. 相似文献
55.
Liliane Viana Pires Adriana Aparecida Siviero-Miachon Angela Maria Spinola-Castro José Alexandre Coelho Pimentel Luciana Sigueta Nishimura Carla Soraya Costa Maia Silvia Maria Franciscato Cozzolino 《Biological trace element research》2017,176(2):217-224
Studies about selenium status in patients with Turner syndrome (TS) are non-existent in the literature. The aim of this study was to evaluate selenium status in patients with TS, while considering the different ages of the studied population and the relation with body composition. In total, 33 patients with TS were evaluated and grouped according to their developmental stages (children, adolescents, and adults). Selenium concentrations in their plasma, erythrocytes, urine, and nails were determined by using hydride generation atomic absorption spectrometry and erythrocyte glutathione peroxidase activity were measured by using Randox commercial kits. Additionally, height, weight, body fat percentage, waist circumference, and waist-height ratio were measured to characterize the patients. No differences in the selenium concentrations in the plasma, erythrocyte, urine, and nails or in the glutathione peroxidase activity were observed among the age groups (p > 0.05). The evaluated selenium levels were less than the established normal ones. The patients with larger waist circumference, body fat percentage, body mass index, and waist-height ratio showed lower glutathione peroxidase enzyme activity (p = 0.023). The present study shows that most patients with TS are deficient in selenium and that those with a greater accumulation of body fat have a lower GPx activity. 相似文献
56.
Soraya Guichard Christian Gary Cherubino Leonardi Nadia Bertin 《Journal of Plant Growth Regulation》2005,24(3):201-213
The influence of air vapor pressure deficit (VPD) and plant fruit load on the expansion and water relations of young tomato
fruits grown in a glasshouse were evaluated under summer Mediterranean conditions. The contributions of phloem, xylem and
transpiration fluxes to the fruit volume increase were estimated at an hourly scale from the growth curves of intact, heat-girdled
and detached fruits, measured using displacement transducers. High VPD conditions reduced the xylem influx and increased the
fruit transpiration, but hardly affected the phloem influx. Net water accumulation and growth rate were reduced, and a xylem
efflux even occurred during the warmest and driest hours of the day. Changes in xylem flux could be explained by variations
in the gradient of water potential between stem and fruit, due to changes in stem water potential. Misting reduced air VPD
and alleviated the reduction in fruit volume increase through an increase in xylem influx and a decrease in fruit transpiration.
Under low fruit load, the competition for assimilates being likely reduced, the phloem flux to fruits increased, similarly
to the xylem and transpiration fluxes, without any changes in the fruit water potential. However, different diurnal dynamics
among treatments assume variable contributions of turgor and osmotic pressure in F3 and F6 fruits, and hypothetical short-term
variations in the water potential gradient between stem and fruit, preventing xylem efflux in F3 fruits. 相似文献
57.
58.
Modulation of stress and virulence in Listeria monocytogenes 总被引:1,自引:0,他引:1
59.
Angelo PC Nunes-Silva CG Brígido MM Azevedo JS Assunção EN Sousa AR Patrício FJ Rego MM Peixoto JC Oliveira WP Freitas DV Almeida ER Viana AM Souza AF Andrade EV Acosta PO Batista JS Walter ME Leomil L Anjos DA Coimbra RC Barbosa MH Honda E Pereira SS Silva A Pereira JO Silva ML Marins M Holanda FJ Abreu RM Pando SC Gonçalves JF Carvalho ML Leal-Mesquita ER da Silveira MA Batista WC Atroch AL França SC Porto JI Schneider MP 《Plant cell reports》2008,27(1):117-124
Guarana (Paullinia cupana var. sorbilis) is a plant native to the central Amazon basin. Roasted seed extracts have been used as medicinal beverages since pre-Colombian
times, due to their reputation as stimulants, aphrodisiacs, tonics, as well as protectors of the gastrointestinal tract. Guarana
plants are commercially cultivated exclusively in Brazil to supply the national carbonated soft-drink industry and natural
product stores around the world. In this report, we describe and discuss the annotation of 15,387 ESTs from guarana seeded-fruits,
highlighting sequences from the flavonoid and purine alkaloid pathways, and those related to biotic stress avoidance. This
is the largest set of sequences registered for the Sapindaceae family. 相似文献
60.