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921.
Suzana Vieira Rabêlo Fernanda Granja da Silva Oliveira Michele Miriam Calixto de Lira Livia Macedo Dutra Adilson Sartoratto Marta Cristina Teixeira Duarte Maria Claudia dos Santos Luciano Maria Francilene Souza Silva Cláudia do Ó Pessoa Manoel Odorico de Moraes Filho Emmanoel Vilaça Costa Jackson Roberto Guedes da Silva Almeida 《Phyton》2021,90(3):921-931
This study aimed to identify the chemical composition of essential oil from fruits (EOAF) and the hexanic crude
extract from aerial parts (At-Hex) of atemoya (Annona cherimola x Annona squamosa), a hybrid belonging to the
Annonaceae family. Cytotoxic and antimicrobial activity was also evaluated. OEAF was obtained by hydrodistillation using a Clevenger apparatus, and their composition was analyzed by gas chromatography-mass spectrometry
(GC-MS) analyses. Cytotoxicity was tested against human tumor cell lines HCT-116 (colon carcinoma), SF-295
(glioblastoma), OVCAR-8 (ovarian carcinoma) and HL60 (leukemia) using 3-(4,5-dimethyl-2-thiazolyl)-2,5-
diphenyl-2H-tetrazolium bromide (MTT) assay, while antimicrobial activity was conducted by bioauthography
method against eleven microorganisms strains. Twenty-four compounds were identified in the EOAF and
twenty-nine in At-Hex. The monoterpenes linalool (25.70%), α-pinene (10.38%), β-pinene (9.12%), transocimene (7.43%), and the sesquiterpene bicyclogermacrene (12.58%) were the major constituents of EOAF,
whereas the sesquiterpene spathulenol (13.91%) was the main compound of At-Hex. At-Hex showed a high
cytotoxicity against SF-295 (glioblastoma). These findings show an important chemotaxonomic contribution
for the Annonaceae family, mainly for the Annona genus. Atemoya proved to be a promising source of substances
with potential cytotoxic activity. 相似文献
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Moreira Camila Francisco Cassini-Vieira Puebla Canesso Maria Cecília Campos Felipetto Mariane Ranfley Hedden Teixeira Mauro Martins Nicoli Jacques Robert Martins Flaviano Santos Barcelos Lucíola Silva 《Probiotics and antimicrobial proteins》2021,13(3):709-719
Probiotics and Antimicrobial Proteins - Skin wounds are an important clinical problem which affects millions of people worldwide. The search for new therapeutic approaches to improve wound healing... 相似文献
924.
Leonardo Tupi Caldas Pereira Lucas Tupi Caldas Pereira Ricardo Sposina Sobral Teixeira Elba Pinto da Silva Bon Suely Pereira Freitas 《Journal of industrial microbiology & biotechnology》2011,38(8):901-907
The aim of this work was to select an efficient impeller to be used in a stirred reactor for the enzymatic hydrolysis of sugar
cane bagasse. All experiments utilized 100 g (dry weight)/l of steam-pretreated bagasse, which is utilized in Brazil for cattle
feed. The process was studied with respect to the rheological behavior of the biomass hydrolysate and the enzymatic conversion
of the bagasse polysaccharides. These parameters were applied to model the power required for an impeller to operate at pilot
scale (100 l) using empirical correlations according to Nagata [16]. Hydrolysis experiments were carried out using a blend of cellulases, β-glucosidase, and xylanases produced in our laboratory
by Trichoderma reesei RUT C30 and Aspergillus awamori. Hydrolyses were performed with an enzyme load of 10 FPU/g (dry weight) of bagasse over 36 h with periodic sampling for the
measurement of viscosity and the concentration of glucose and reducing sugars. The mixture presented pseudoplastic behavior.
This rheological model allowed for a performance comparison to be made between flat-blade disk (Rushton turbine) and pitched-blade
(45°) impellers. The simulation showed that the pitched blade consumed tenfold less energy than the flat-blade disk turbine.
The resulting sugar syrups contained 22 g/l of glucose, which corresponded to 45% cellulose conversion. 相似文献
925.
Michelin M Polizeli Mde L Silva DP Ruzene DS Vicente AA Jorge JA Terenzi HF Teixeira JA 《Journal of industrial microbiology & biotechnology》2011,38(12):1979-1984
Fungi producing high xylanase levels have attracted considerable attention because of their potential industrial applications.
Batch cultivations of Aspergillus terricola fungus were evaluated in stirred tank and airlift bioreactors, by using wheat bran particles suspended in the cultivation
medium as substrate for xylanase and β-xylosidase production. In the stirred tank bioreactor, in physical conditions of 30°C,
300 rpm, and aeration of 1 vvm (1 l min−1), with direct inoculation of fungal spores, 7,475 U l−1 xylanase was obtained after 36 h of operation, remaining constant after 24 h. In the absence of air injection in the stirred
tank reactor, limited xylanase production was observed (final concentration 740 U l−1). When the fermentation process was realized in the airlift bioreactor, xylanase production was higher than that observed
in the stirred tank bioreactor, being 9,265 U l−1 at 0.07 vvm (0.4 l min−1) and 12,845 U l−1 at 0.17 vvm (1 l min−1) aeration rate. 相似文献
926.
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929.
Viana GM de Lima NO Cavaleiro R Alves E Souza IC Feio R Leistner-Segal S Schwartz I Giugliani R da Silva LC 《Genetics and molecular biology》2011,34(3):410-415
Mucopolysaccharidoses (MPS) are rare lysosomal disorders caused by the deficiency of specific lysosomal enzymes responsible for glycosaminoglycan (GAG) degradation. Enzyme Replacement Therapy (ERT) has been shown to reduce accumulation and urinary excretion of GAG, and to improve some of the patients' clinical signs. We studied biochemical and molecular characteristics of nine MPS patients (two MPS I, four MPS II and three MPS VI) undergoing ERT in northern Brazil. The responsiveness of ERT was evaluated through urinary GAG excretion measurements. Patients were screened for eight common MPS mutations, using PCR, restriction enzyme tests and direct sequencing. Two MPS I patients had the previously reported mutation p.P533R. In the MPS II patients, mutation analysis identified the mutation p.R468W, and in the MPS VI patients, polymorphisms p.V358M and p.V376M were also found. After 48 weeks of ERT, biochemical analysis showed a significantly decreased total urinary GAG excretion in patients with MPS I (p < 0.01) and MPS VI (p < 0.01). Our findings demonstrate the effect of ERT on urinary GAG excretion and suggest the adoption of a screening strategy for genotyping MPS patients living far from the main reference centers. 相似文献
930.
Pollen transport to a receptive stigma can be facilitated through different pollinators, which submits the pollen to different selection pressures. This study aimed to associate pollen and stigma morphology with zoophily in species of the tribe Phaseoleae. Species of the genera Erythrina, Macroptilium and Mucuna with different pollinators were chosen. Pollen grains and stigmas were examined under light microscopy (anatomy), scanning electronic microscopy (surface analyses) and transmission electronic microscopy (ultrastructure). The three genera differ in terms of pollen wall ornamentation, pollen size, pollen aperture, thickness of the pollen wall, amount of pollenkitt, pollen hydration status and dominant reserves within the pollen grain, while species within each genus are very similar in most studied characteristics. Most of these features lack relationships to pollinator type, especially in Erythrina and Mucuna. Pollen reserves are discussed on a broad scale, according to the occurrence of protein in the pollen of invertebrate- or vertebrate-pollinated species. Some pollen characteristics are more associated to semi-dry stigma requirements. This apical, compact, cuticularised and secretory stigma occurs in all species investigated. We conclude that data on pollen and stigma structure should be included together with those on floral morphology and pollinator behaviour for the establishment of functional pollination classes. 相似文献