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51.
Flavio Alexandre Carvalho Natália Valadares de Moraes Antônio Eduardo Miller Crotti Eduardo José Crevelin André Gonzaga dos Santos 《化学与生物多样性》2023,20(9):e202300492
Casearia species are found in the America, Africa, Asia, and Australia and present pharmacological activities, besides their traditional uses. Here, we reviewed the chemical composition, content, pharmacological activities, and toxicity of the essential oils (EOs) from Casearia species. The EO physical parameters and leaf botanical characteristics were also described. The bioactivities of the EOs from the leaves and their components include cytotoxicity, anti-inflammatory, antiulcer, antimicrobial, antidiabetic, antioxidant, antifungal, and antiviral activities. The main components associated with these activities are the α-zingiberene, (E)-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, α-humulene, β-acoradiene, and δ-cadinene. Data on the toxicity of these EOs are scarce in the literature. Casearia sylvestris Sw. is the most studied species, presenting more significant pharmacological potential. The chemical variability of EOs components was also investigated for this species. Caseria EOs have relevant pharmacological potential and must be further investigated and exploited. 相似文献
52.
Coelho-Rocha Nina Dias de Jesus Luís Cláudio Lima Barroso Fernanda Alvarenga Lima da Silva Tales Fernando Ferreira Enio Gonçalves José Eduardo dos Santos Martins Flaviano de Oliveira Carvalho Rodrigo Dias Barh Debmalya Azevedo Vasco Ariston de Carvalho 《Probiotics and antimicrobial proteins》2023,15(1):160-174
Probiotics and Antimicrobial Proteins - Beneficial effects of Lactiplantibacillus plantarum strains have been widely reported. Knowing that the effects of probiotic bacteria are strain-dependent,... 相似文献
53.
Viviane Fátima de Oliveira Lucas Figueiredo Gabriel de Oliveira Correia Maria de Fátima Pires da Silva Machado Hugo Zeni Neto Wanderley Dantas dos Santos Claudete Aparecida Mangolin 《Global Change Biology Bioenergy》2023,15(12):1465-1476
The burgeoning cellulosic ethanol industry necessitates advancements in enzymatic saccharification, effective pretreatments for lignin removal, and the cultivation of crops more amenable to saccharification. Studies have demonstrated that natural inhibitors of lignin biosynthesis can enhance the saccharification of lignocellulose, even in tissues generated several months post-treatment. In this study, we applied daidzin (a competitive inhibitor of coniferaldehyde dehydrogenase), piperonylic acid (a quasi-irreversible inhibitor of cinnamate 4-hydroxylase), and methylenedioxy cinnamic acid (a competitive inhibitor of 4-coenzyme A ligase) to 60-day-old crops of two conventional Brazilian sugarcane cultivars and two energy cane clones, bred specifically for enhanced biomass production. The resultant biomasses were evaluated for lignin content and enzymatic saccharification efficiency without additional lignin-removal pretreatments. The treatments amplified the production of fermentable sugars in both the sugarcane cultivars and energy cane clones. The most successful results softened the most recalcitrant lignocellulose to the level of the least recalcitrant of the biomasses tested. Interestingly, the softest material became even more susceptible to saccharification. 相似文献
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J. A. González V. Rico J. M. Lorenzo S. Reis J. G. Pajuelo M. Afonso Dias A. Mendonça H. M. Krug M. R. Pinho 《Zeitschrift fur angewandte Ichthyologie》2003,19(2):104-108
This paper provides comparative information on the reproductive biology of the alfonsino, Beryx splendens Lowe, 1834, species with commercial interest in the Azores, Madeira and the Canary Islands. A total of 846 individuals from Azores (14.0–42.0 cm fork length), 621 from Madeira (17.2–50.0 cm fork length) and 643 from the Canaries (18.2–38.9 cm fork length) were used for the study. The alfonsino is gonochoric with no evidence of sexual dimorphism. Females are more abundant than males; this dominance probably reflects certain differences in the spatial distribution and/or the catchability of males and females in the Macaronesian archipelagos. The spawning season was distinct for the three Macaronesian areas, with an observed North–South variation in the reproductive period: September–March in the Azores, March–June in Madeira and July–September in the Canary Islands. The size at sexual maturity estimated for Madeira and the Canary Islands is similar (32 and 30 cm fork length, respectively), while for the Azores it is reached at smaller length (23 cm fork length). The differences observed in the size at sexual maturity can be explained by the different exploitation levels in each archipelago. Life‐history parameters of the alfonsino suggest that this species has a specialistic life‐history strategy and fisheries based on this species are more susceptible to growth overfishing and population depletion. 相似文献
57.
James L. Patton Sergio F. dos Reis Maria Nazareth F. da Silva 《Journal of Mammalian Evolution》1996,3(1):3-29
Variation in the mitochondrial cytochrome b gene (nucleotide and amino acid sequences) is evaluated for 9 genera and 15 species of American opossums in the family Didelphidae, using the American caenolestid rat opossumLestoros and the New Guinean peroryctid bandicootEchimypera as outgroups. Phylogenetic analyses (parsimony and distance) strongly support the monophyly of the Didelphidae and delineate two major clades; (1)Didelphis andPhilander are strongly aligned sister taxa, withMetachirus weakly but consistently associated with them, and (2)Marmosa plusMicoureus, withMonodelphis falling outside that pair. The generaMarmosops, Caluromys, andGlironia exhibit varied relationships, depending upon the method of analysis and data (DNA or amino acid sequences) used, but generally are placed individually or in combinations near or at the base of the didelphid radiation. Some aspects of these relationships are consistent with current taxonomic views, but others are in marked contrast. Specifically, a clade comprised of the mouse opossumsMarmosa, Micoureus, andMarmosops is strongly rejected by log-likelihood analysis, contrary to expectations from some current classifications. Also, the woolly opossumsCaluromys andGlironia also do not form a sister-taxon relationship, as suggested by their placement in a subfamily separate from the remaining didelphids examined. However, such a relationship cannot be rejected from log-likelihood analyses. The relationships suggested fromcyt-b sequences are strongly concordant with those based on DNA-DNA hybridization analyses. In addition to systematic and phylogenetic properties, molecular evolution of the didelphid cytochrome b gene sequence is characterized according to nucleotide bias and rate differentials at each codon position and across the entire sequence.To whom correspondence should be addressed. 相似文献
58.
Regulation of Phenylethanolamine N-Methyltransferase Gene Expression by Imidazoline Receptors in Adrenal Chromaffin Cells 总被引:2,自引:1,他引:1
Marian J. Evinger Paul Ernsberger †Soundararajan Regunathan †Donald J. Reis 《Journal of neurochemistry》1995,65(3):988-997
Abstract: As adrenal medullary chromaffin cells express imidazoline binding sites in the absence of α2 -adrenergic receptors, these cells provide an ideal system in which to determine whether imidazolines can influence catecholamine gene expression through nonadrenergic receptors. This study evaluates the ability of clonidine and related drugs to regulate expression of the gene for the epinephrine-synthesizing enzyme phenylethanolamine N -methyltransferase (PNMT) in the rat adrenal gland and in bovine adrenal chromaffin cell cultures. In vivo, PNMT and tyrosine hydroxylase (TH) mRNA levels increase in rat adrenal medulla after a single injection of clonidine. Clonidine also dose-dependently stimulates PNMT mRNA expression in vitro in primary cultures of bovine chromaffin cells, with a threshold dose of 0.1 μ M . Other putative imidazoline receptor agonists, including cimetidine, rilmenidine, and imidazole-4-acetic acid, likewise enhance PNMT mRNA production showing relative potencies that correlate with their binding affinities at chromaffin cell I1 -imidazoline binding sites. The effects of clonidine on PNMT mRNA appear to be distinct from and additive with those exerted by nicotine. Moreover, neither nicotinic antagonists nor calcium channel blockers, which attenuate nicotine's influence on PNMT mRNA production, diminish clonidine's effects on PNMT mRNA. Although 100 μ M clonidine diminishes nicotine-stimulated release of epinephrine and norepinephrine in chromaffin cells, this effect appears unrelated to stimulation of imidazoline receptor subtypes. This is the first report to link imidazoline receptors to neurotransmitter gene expression. 相似文献
59.
Genetic Structure of Acetobacter diazotrophicus Populations and Identification of a New Genetically Distant Group 总被引:3,自引:1,他引:2
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J. Caballero-Mellado L. E. Fuentes-Ramirez V. M. Reis E. Martinez-Romero 《Applied microbiology》1995,61(8):3008-3013
A total of 55 isolates of Acetobacter diazotrophicus recovered from diverse sucrose-rich host plants and from mealybugs associated with sugarcane plants were characterized by the electrophoretic mobilities of 12 metabolic enzymes. We identified seven different electrophoretic types (ETs), six of which are closely related within a genetic distance of 0.195 and exhibit high DNA-DNA homology. The seventh ET was largely divergent, separated at a genetic distance of 0.53, and had only 54% DNA homology to the reference strain. Strains corresponding to ET 7 could represent a distinct nitrogen-fixing species of the genus Acetobacter. More genetic diversity was found in isolates from Brazil than in those from Mexico, probably due to the very different crop nitrogen fertilization levels used. 相似文献
60.
Michele Yarnall Kathleen J. Reis Elia M. Ayoub Michael D.P. Boyle 《Journal of microbiological methods》1984,3(2):83-93
A rapid semiquantitative procedure that enables bacteria to be screened for surface or secreted receptors for the Fc region of human IgG is described. Surface Fc receptors were detected by direct transfer of bacterial colonies to nitrocellulose by electroblotting and then probing with 125I-labeled human IgG in the presence of a two fold molar excess of unlabeled F(ab′)2fragments. The blots were exposed to X-ray film and the intensity of the resulting autoradiograph was a measure of surface Fc receptors expression. This procedure reliably distinguished Staphylococcus aureus strains which expressed different levels of surface Fc receptors. When applied to the study of group A streptococci, a number of Fc receptor-positive strains were identified. Unlike the homogeneous Fc receptor expression on individual colonies of the staphylococcal strains, a wide variation in the level of Fc receptor expression was observed within a given streptococcal strain. Group A streptococcal substrains which expressed high and low levels of surface Fc receptors could be isolated from replica plates.Secreted Fc receptors were measured by a simple modification of the blotting procedure in which the nitrocellulose was placed on the opposite side of the agar from the bacterial colonies. Secreted Fc receptors was electroblotted through the agar onto nitrocellulose and probed as described above. This approach readily detected nanogram quantities of secreted type I Fc receptor (protein A) from the Staphylococcus aureus Cowan strain. None of the group A streptococcal strains tested were found to secrete detectable quantities of Fc receptors. 相似文献