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141.
Faria Lua Figueiredo Solange Regina Campos Viana Vera Simões Cláudia Albarello Norma Carlos Trugo Luiz Auxiliadora Coelho Kaplan Maria Krul William Robert 《Plant Cell, Tissue and Organ Culture》1999,56(2):121-124
Rollinia mucosa produces furofuranic lignans (magnolin, epiyangambin, yangambin) that are antagonists of platelet-activating
factor (PAF). The biosynthetic capacity and the potential for the accumulation of furofuranic lignans, including epieudesmin,
of the plants cultured both in vivo and in vitro conditions were evaluated. The production and the pattern of lignans accumulated
were dependent on the origin of the plant material and the plant organ. The major accumulation of lignans was observed in
leaves. In the mature leaves of in vivo grown seedlings magnolin and yangambin predominated, in contrast to leaves from in
vitro propagated plants that presented epiyangambin as the major lignan.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
142.
Experiments were carried out to investigate the effects of different degrees of water stress on cowpea in the presence and
absence of Bradyrhizobium spp. inoculation and to evaluate physiological responses to stress. The soil used was Yellow Latosol, pH 6.3 and the crop
used was cowpea (Vigna unguiculata (L.) Walp.) cv. ‘IPA 204’. Stress was applied continuously by the control of matric potential (ψ
m
) through a porous cup. The lowered soil ψ
m
had a direct effect on the N2 fixation, but the strains Bradyrhizobium introduced by inoculation in the cowpea plants were superior to the indigenous strain demonstrating the importance of inoculation
in the stressed plants. At the more negative ψ
m
plants inoculated with the strains EI 6 formed associations of greater symbiotic efficiency which helped the cowpea plants
to withstand drought stress better than the strain BR 2001 and the uninoculated control. The leghaemoglobin concentration
was not inhibited in the drought-stressed plants at ψ
m
-70 kPa when inoculated with the strain EI 6, which confered a differential degree of drought resistance in plants. The ψ
w
declined in the stressed plants reaching values of -1.0 MPa which was sufficient to cause disturbance in nodulation and biomass
production.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
143.
144.
Maria de Fátima Silva Lopes Ana Lúcia Leitão J.J. Figueiredo Marques Manuel José Teixeira Carrondo Maria Teresa Barreto Crespo 《FEMS microbiology letters》1999,176(2):483-487
The hypothesis of a proteolytic involvement in the extracellular lipase processing of a strain of Lactobacillus plantarum was considered and tested, in vitro assays with acid proteases, cathepsin D and renin revealed that both did affect lipolytic activity positively. In vivo assays with growth in the presence of the protease inhibitors pepstatin, phenylmethylsulfonyl fluoride, transepoxysuccinyl-L-leucylamido-(4-guanidino)butane and ethylenediaminetetraacetic acid showed that ethylenediaminetetraacetic acid did affect the pattern of the proteins that possess lipolytic activity. Therefore, it is suggested that a metalloprotease is involved in the processing of the extracellular lipases of L. plantarum, although other proteases can also be important. 相似文献
145.
Study of preantral follicle population in situ and after mechanical isolation from caprine ovaries at different reproductive stages. 总被引:1,自引:0,他引:1
C M Lucci C A Amorim A P Rodrigues J R Figueiredo S N Báo J R Silva P B Gon?alves 《Animal reproduction science》1999,56(3-4):223-236
The purposes of this study were to estimate the population of caprine preantral follicles, and to evaluate quantitatively and qualitatively the efficiency of a specific mechanical method for the isolation of preantral follicles from mixed breed goats at different reproductive stages. On average, 37,646+/-4277 preantral follicles were present in goat ovaries, and 13,631+/-2399 preantral follicles were obtained after isolation. The number of preantral follicles isolated or in situ was not significantly affected by the reproductive stage. The mean recovery rate per ovary ([number of isolated follicles/number of in situ follicles] x 100) of isolated follicles was 36.2%. The distribution of follicles in situ was 67.8% primordial, 25.8% primary and 6.4% secondary; the respective distribution after isolation was 93.8%, 5.2% and 1.0%. In this study, many polyovular follicles were also observed, mainly in prepubertal goat ovaries. Histological analysis showed that few preantral follicles were atretic in situ (4.83%+/-0.35) or after the isolation procedure (4.67%+/-0.65) in the three reproductive stages. The percentage of atretic follicles was not affected either by the mechanical method or by the reproductive stage. It is concluded that a large number of preantral follicles can be successfully isolated mechanically, with a high recovery rate and a low rate of follicular atresia, irrespective of the reproductive stage of the caprine female. 相似文献
146.
Figueiredo Douglas B. Carvalho Eneas Santos Mauricio P. Kraschowetz Stefanie Zanardo Rafaela T. Campani Gilson Silva Gabriel G. Sargo Cíntia R. Horta Antonio Carlos L. de C. Giordano Roberto Miyaji Eliane N. Zangirolami Teresa C. Cabrera-Crespo Joaquin Gonçalves Viviane Maimoni 《Applied microbiology and biotechnology》2017,101(6):2305-2317
Applied Microbiology and Biotechnology - Streptococcus pneumoniae is the main cause of pneumonia, meningitis, and other conditions that kill thousands of children every year worldwide. The... 相似文献
147.
Carla Malaquias Almeida Jos A. Manso Ana C. Figueiredo Liliana Antunes Rui Cruz Bruno Manadas Daniel Bur Pedro Jos Barbosa Pereira Carlos Faro Isaura Simes 《Applied microbiology and biotechnology》2017,101(18):6951-6968
The potential of using a synthetic cardosin-based rennet in cheese manufacturing was recently demonstrated with the development and optimization of production of a recombinant form of cardosin B in Kluyveromyces lactis. With the goal of providing a more detailed characterization of this rennet, we herein evaluate the impact of the plant-specific insert (PSI) on cardosin B secretion in this yeast, and provide a thorough analysis of the specificity requirements as well as the biochemical and structural properties of the isolated recombinant protease. We demonstrate that the PSI domain can be substituted by different linker sequences without substantially affecting protein secretion and milk clotting activity. However, the presence of small portions of the PSI results in dramatic reductions of secretion yields in this heterologous system. Kinetic characterization and specificity profiling results clearly suggest that synthetic cardosin B displays lower catalytic efficiency and is more sequence selective than native cardosin B. Elucidation of the structure of synthetic cardosin B confirms the canonical fold of an aspartic protease with the presence of two high mannose-type, N-linked glycan structures; however, there are some differences in the conformation of the flap region when compared to cardosin A. These subtle variations in catalytic properties and the more stringent substrate specificity of synthetic cardosin B help to explain the observed suitability of this rennet for cheese production. 相似文献
148.
Rafaelle Fonseca de Matos Lúcia Carla Vasconcelos Mendonça Kaira Geiliane da Silva Souza Adriana Aparecida Durães Fonseca Elaine Mirla Souza Costa Marcus Vinicius Dias de Lima José Maria dos Santos Vieira Mioni Thielli Figueiredo Magalhães de Brito Marta Chagas Monteiro 《Folia microbiologica》2017,62(2):169-174
Certain non-steroidal anti-inflammatory drugs can inhibit fungal growth, fungal prostaglandin E2 production, and enzyme activation. This study aims to investigate the antifungal effect of nimesulide against pathogenic filamentous fungi and yeast. The experiments detailed below were also designed to investigate whether the action is dependent on E2 fungal prostaglandins. Our data showed that nimesulide exhibited potent antifungal activity, mainly against Trichophyton mentagrophytes (ATCC 9533) and Cryptococcus neoformans with MIC values of 2 and 62 μg/mL, respectively. This drug was also able to inhibit the growth of clinic isolates of filamentous fungi, such as Aspergillus fumigatus, and dermatophytes, such as T. rubrum, T. mentagrophytes, Epidermophyton floccosum, Microsporum canis, and M. gypseum, with MIC values ranging from 112 to 770 μg/mL. Our data also showed that the inhibition of fungal growth by nimesulide was mediated by a mechanism dependent on PGE2, which led to the inhibition of essential fungal enzymes. Thus, we concluded that nimesulide exerts a fungicidal effect against pathogenic filamentous fungi and yeast, involving the inhibition of fungal prostaglandins and fungal enzymes important to the fungal growth and colonization. 相似文献
149.
Júnia Rafael Mendonça Figueiredo Patrícia Duarte de Oliveira Paiva Michele Valquíria dos Reis Fernanda Carlota Nery Samantha de Menezes Campos Diogo Pedrosa Corrêa da Silva Renato Paiva 《Acta Physiologiae Plantarum》2017,39(7):147
Soil salinity is mainly caused by excessive use of fertilizers and the use of poor quality water, and adversely affected crop growth especially when grown in protected environments. Soil salinity causes salt stress in plants, which inhibits plant growth, leading to morphological, metabolic and physiological changes. Though it is a major problem occurs more frequently, there is less information on the behavior of calla lily (Zantedeschia aethiopica) under these conditions, and most studies are conducted with other species of the genus Zantesdeschia. Therefore, this study aimed to evaluate ecophysiological, biochemical and anatomical growth responses of calla lily plants to salt stress. Rhizomes were grown in trays containing coconut fiber as a substrate and treated with 0, 25, 50, 75 and 100 mM NaCl to induce stress. A decrease in plant height was observed, as well as in the number of tillers and leaves, main root length, fresh and dry matter of the shoot and root system. A reduction in photosynthetic rate, stomatal conductance and transpiration rate was observed at 60 days. However, after 90 days, the photosynthetic rate was unchanged, with increased stomatal conductance and transpiration rate for plants exposed to 75 mM NaCl. Salt stress caused a higher accumulation of carbohydrates in shoots and roots. Thus, high concentrations of NaCl affect the development of calla lily, indicating that this species is susceptible to salt stress. 相似文献
150.
Larissa Arrais Guimaraes Ana Paula Zotta Mota Ana Claudia Guerra Araujo Lucio Flavio de Alencar Figueiredo Bruna Medeiros Pereira Mario Alfredo de Passos Saraiva Raquel Bispo Silva Etienne G. J. Danchin Patricia Messenberg Guimaraes Ana Cristina Miranda Brasileiro 《Plant molecular biology》2017,93(1-2):79-96