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991.
Kouadio Ibrahime Sinan Abdurrahman Aktumsek María de la Luz Cádiz-Gurrea Francisco Javier Leyva-Jiménez Álvaro Fernández-Ochoa Antonio Segura-Carretero Jasmina Glamocilja Marina Sokovic Marija Nenadić Gokhan Zengin 《化学与生物多样性》2021,18(8):e2100299
The article reports the chemical composition, antioxidant, six key enzymes inhibitory and antimicrobial activities of two solvent extracts (water and methanol) of leaves and stem bark of Uapaca togoensis. For chemical composition, methanol extract of stem bark exhibited significant higher total phenolic (129.86 mg GAE/g) and flavanol (10.44 mg CE/g) contents. Methanol extract of leaves and water extract of stem bark showed high flavonoids (20.94 mg RE/g) and phenolic acid (90.40 mg CAE/g) content, respectively. In addition, HPLC-ESI-TOF-MS analysis revealed that U. togoensis was rich in procyanidins. The methanol and water extracts of stem bark had overall superior antioxidant activity; however, only methanol extract of stem bark showed higher inhibition of cholinesterase (AChE: 2.57 mg GALAE/g; BChE: 4.69 mg GALAE/g), tyrosinase (69.53 mg KAE/g) and elastase (2.73 mmol CE/g). Potent metal chelating ability was showed by water extract of leaves (18.94 mg EDTAE/g), higher inhibition of amylase was detected for water extracts of leaves (0.94 mmol ACAE/g) and stem bark (0.92 mmol ACAE/g). The tested extracts have shown wide-spectrum antibacterial properties and these effects have shown to be more effective against Aspergillus ochraceus, Penicillium funiculosum, Trichoderma viride, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. The results revealed that the antioxidant, enzyme inhibitory and antimicrobial activities depended on the extraction solvents and the parts of plant. Bioinformatics analysis on the 17 major compounds showed modulation of pathway associated with cancer. In brief, U. togoensis might be valuable as potential source of natural agents for therapeutic application. 相似文献
992.
993.
Luana Alves Rodrigues Eduardo Augusto Ruas Paulo Maurício Ruas Maikel Reck Fernando Gianetti Fiorin María Ángeles Ortiz Estrella Urtubey Nelson Ivo Matzenbacher Claudete Fátima Ruas 《Plant Species Biology》2016,31(1):55-64
The genus Hypochaeris has a recent evolutionary history caused by long‐distance dispersal in conjunction with adaptive radiation in the South American continent. Hypochaeris lutea is a perennial herb that grows mostly at altitudes of around 1000 m in cold swamps of the southern regions of Brazil. We investigated the amplified fragment length polymorphism (AFLP) in 270 individuals representing 11 Brazilian populations of H. lutea to elucidate the population genetic structure of this species. The frequencies of polymorphic loci and gene diversity ranged from 83.42% to 91.66% and from 0.26 to 0.34, respectively. Analysis of molecular variance revealed that most of the genetic variability was found within (76.67%) rather than among (23.3%) populations, agreeing with the pattern of genetic distribution within and among populations observed in other allogamous species of Hypochaeris. A Mantel test showed no correlation between genetic and geographic distances when all populations were considered. Simulations performed using a Bayesian approach consistently identified two clusters with different admixture proportions of individuals, as also revealed by a UPGMA dendrogram of populations. The pattern of genetic structure observed in H. lutea is consistent with a process of successive colonization events by long‐distance dispersal resembling the rapid and recent radiation that has been proposed to explain the origin of the South American species of Hypochaeris. 相似文献
994.
Joaquín Herrero Francisco Fernández-Pérez Tatiana Yebra Esther Novo-Uzal Federico Pomar Mª Ángeles Pedreño Juan Cuello Alfredo Guéra Alberto Esteban-Carrasco José Miguel Zapata 《Planta》2013,237(6):1599-1612
Lignins result from the oxidative polymerization of three hydroxycinnamyl (p-coumaryl, coniferyl, and sinapyl) alcohols in a reaction mediated by peroxidases. The most important of these is the cationic peroxidase from Zinnia elegans (ZePrx), an enzyme considered to be responsible for the last step of lignification in this plant. Bibliographical evidence indicates that the arabidopsis peroxidase 72 (AtPrx72), which is homolog to ZePrx, could have an important role in lignification. For this reason, we performed a bioinformatic, histochemical, photosynthetic, and phenotypical and lignin composition analysis of an arabidopsis knock-out mutant of AtPrx72 with the aim of characterizing the effects that occurred due to the absence of expression of this peroxidase from the aspects of plant physiology such as vascular development, lignification, and photosynthesis. In silico analyses indicated a high homology between AtPrx72 and ZePrx, cell wall localization and probably optimal levels of translation of AtPrx72. The histochemical study revealed a low content in syringyl units and a decrease in the amount of lignin in the atprx72 mutant plants compared to WT. The atprx72 mutant plants grew more slowly than WT plants, with both smaller rosette and principal stem, and with fewer branches and siliques than the WT plants. Lastly, chlorophyll a fluorescence revealed a significant decrease in ΦPSII and q L in atprx72 mutant plants that could be related to changes in carbon partitioning and/or utilization of redox equivalents in arabidopsis metabolism. The results suggest an important role of AtPrx72 in lignin biosynthesis. In addition, knock-out plants were able to respond and adapt to an insufficiency of lignification. 相似文献
995.
Álvarez-García Ó García-López E Loredo V Gil-Peña H Mejía-Gaviria N Rodríguez-Suárez J Ordóñez FÁ Santos F 《PloS one》2012,7(4):e34788
Rapamycin, an immunosuppressant agent used in renal transplantation with antitumoral properties, has been reported to impair longitudinal growth in young individuals. As growth hormone (GH) can be used to treat growth retardation in transplanted children, we aimed this study to find out the effect of GH therapy in a model of young rat with growth retardation induced by rapamycin administration. Three groups of 4-week-old rats treated with vehicle (C), daily injections of rapamycin alone (RAPA) or in combination with GH (RGH) at pharmacological doses for 1 week were compared. GH treatment caused a 20% increase in both growth velocity and body length in RGH animals when compared with RAPA group. GH treatment did not increase circulating levels of insulin-like growth factor I, a systemic mediator of GH actions. Instead, GH promoted the maturation and hypertrophy of growth plate chondrocytes, an effect likely related to AKT and ERK1/2 mediated inactivation of GSK3β, increase of glycogen deposits and stabilization of β-catenin. Interestingly, GH did not interfere with the antiproliferative and antiangiogenic activities of rapamycin in the growth plate and did not cause changes in chondrocyte autophagy markers. In summary, these findings indicate that GH administration improves longitudinal growth in rapamycin-treated rats by specifically acting on the process of growth plate chondrocyte hypertrophy but not by counteracting the effects of rapamycin on proliferation and angiogenesis. 相似文献
996.
997.
Daniel Augusto Schurt Ueder Pedro Lopes Henrique Silva Silveira Duarte Fabrício Ávila Rodrigues 《Journal of Phytopathology》2015,163(4):310-313
This study investigated the effect of potassium (K) on sheath blight (Rhizoctonia solani) development on rice plants from cultivars BR‐IRGA 409 and Labelle grown in nutrient solution containing 0, 50 and 100 mm of K. Sheath blight progress on inoculated sheaths was evaluated by measuring the relative lesion length at 48, 72, 96 and 120 h after inoculation (hai). Data were used to calculate the area under relative lesion length progress curve (AURLLPC). The foliar K concentration on leaf sheaths tissue increased by 61.48 and 116.05% to cultivars BR‐IRGA 409 and Labelle, respectively, as the K rates increased from 0 to 100 mm . A linear model best described the relationship between the AURLLPC and the K rates. The AURLLPC decreased by 29.2 and 21.3% for cultivars BR‐IRGA 409 and Labelle, respectively, as the K rates in the nutrient solution increased. It can be concluded that high K concentration on leaf sheaths tissue was important to decrease sheath blight symptoms on rice leaf sheaths. 相似文献
998.
Xoaquín Moreira Luis Abdala-Roberts Pieter De Frenne Andrea Galmán Álvaro Gaytán Raimo Jaatinen Beatriz Lago-Núñez Camille Meeussen Pertti Pulkkinen Pil U. Rasmussen Jan P.J.G. Ten Hoopen Bart G.H. Timmermans Carla Vázquez-González Nick Bos Bastien Castagneyrol Ayco J.M. Tack 《American journal of botany》2021,108(1):172-176
999.
1000.
A phylogeny of the Cambrian solenopleuropsine trilobites is constructed to evaluate the importance of differential speciation, extinction and developmental constraints in the evolutionary history of the clade. The transformation of the Pardailhania–Solenopleuropsis ( Manublesia )– Solenopleuropsis ( Solenopleuropsis ) lineages occurred during the mid Caesaraugustian–early Languedocian interval, with all measured morphological variables exhibiting continuous and gradual changes. Several evolutionary trends show tendencies towards an increase in tuberculation and its complexity on the anterior part of the cephalon. A mid Caesaraugustian anagenetic tendency is related to the influence of constant environmental conditions, whereas a late Caesaraugustian–early Languedocian cladogenetic tendency seems to have been an adaptative response to unstable environments. The Solenopleuropsinae clade has a well-preserved continuous fossil record over its full biogeographical range in the Mediterranean region. The sympatric evolution in centrally located populations (Mediterranean area) follows the model of phyletic gradualism, whilst a peripheral population in Avalonia gave rise (by allopatric speciation) to a distinct species, characterized by a variation in the relative size of the palpebral lobes, which may be evidence of a parallel evolution in the trends of ornamentation. 相似文献