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991.
992.
Decolorization of textile dyes by enzymatic extract and submerged cultures of <Emphasis Type="Italic">Pleurotus sajor-caju</Emphasis> 总被引:1,自引:0,他引:1
Fernanda M. Munari Tamara A. Gaio Raquel Calloni Aldo J. P. Dillon 《World journal of microbiology & biotechnology》2008,24(8):1383-1392
Pleurotus sajor-caju PS2001 was screened in Petri dish plates to assess the dye-decolorizing ability of industrial textile dyes. P. sajor-caju PS2001 was also cultivated in solid-state fermentation containing sawdust of Pinus sp. and wheat bran to obtain the enzymatic extract, showing laccase and manganese-peroxidase activity, which was used to
test the capacity to degrade the textile dyes. Additional tests of decolorization were performed in liquid cultures. Anthraquinone-type
textile dyes proved to be substrates for the enzymatic system of P. sajor-caju PS2001. Cultures in Petri dish plates showed that the anthraquinone dye Reactive Blue 220 can act as a redox mediator for
the enzymatic reactions involved in the decolorization process, and enables the azo dye degradation. Reactive Blue 220 and
Acid Blue 280 were completely decolorized in 30 min and 60 min, respectively, during the tests with precipitated enzymatic
extract, while the azo dyes showed resistance to degradation. Additionally, in submerged cultures with dyes, veratryl alcohol
oxidases and lignin peroxidase activities were observed. These results suggest that the strain P. sajor-caju PS2001 has great potential for use in the bioremediation technology of recalcitrant pollutant such as textile effluents. 相似文献
993.
994.
995.
Cristina Peggion Fernando Formaggio Marco Crisma Raquel F Epand Richard M Epand Claudio Toniolo 《Journal of peptide science》2003,9(11-12):679-689
Lipopeptaibols are members of a novel family of naturally occurring, short peptides with antimicrobial activity, characterized by a lipophilic acyl chain at the N-terminus, a high content of turn/helix inducing alpha-aminoisobutyric acid and a 1,2-amino alcohol at the C-terminus. Using solution methods, the prototypical lipopeptaibol trichogin GA IV and a large series of appropriately designed analogues were synthesized, which allow: (i) determination of the minimal lipid chain and peptide main-chain lengths for the onset of membrane activity, and (ii) exploitation of a number of physico-chemical techniques aimed at assessing the trichogin preferred conformation under a variety of conditions and at investigating its mechanism of interaction with the phospholipid membranes. 相似文献
996.
Rodrigo de Cássio da Silva Rafael Rosas Oliveira Sandra Maria Feliciano de Oliveira Azevedo Raquel Moares Soares Valéria Freitas De Magalhães 《Journal of fish biology》2021,99(4):1274-1279
Cylindrospermopsin (CYN) is a cyanotoxin that has raised serious concerns about public health in many parts of the world. It can bioaccumulate and affect the health of aquatic organisms, but despite this, few studies have been conducted on CYN uptake and clearance in fish. In this paper, the authors evaluate the uptake and clearance of CYN in the muscle tissue and viscera of juvenile tilapia (Oreochromis niloticus) after exposure to aqueous extracts and whole cells of Cylindrospermopsis raciborskii (CYN-producer). CYN blended with commercial fish food, and three experiments were conducted. In the first trial, fish food, and aqueous extracts containing 0.31 μg CYN g−1 of food per day, was administered to tilapia for 15 days. In the second trial, fish were provided food and intact cells (5.4 μg CYN g−1 of food per day) for 15 days. In the last trial, they were provided fish food and aqueous extracts (0.8 μg CYN g−1 of food per day) for 12 days, and for the next 10 days, the animals were fed food without toxic cell extracts (to simulate a clearance period). The concentration of CYN in muscle tissue and viscera was analysed using ELISA. In the case of juvenile tilapia, the presence of CYN was higher in viscera than in muscle tissue, and the toxin remained in the tissues even after 10 days without the addition of contaminated food. The results suggest that tilapia represents a potential source of CYN transfer through the food web, and this shows the need for a continuous monitoring of this compound in organisms that are used for human and animal consumption. 相似文献
997.
Eleonora Regueira María Florencia Scaia María Clara Volonteri Nora Raquel Ceballos 《Journal of morphology》2013,274(3):331-343
The interrenal gland of anurans synthesizes the steroids aldosterone and corticosterone, but it is unknown whether these hormones are synthesized by the same cell type. In this work, we aim to elucidate whether there are different steroidogenic cell types and whether they have specific regionalization in the interrenal gland of the male toad Rhinella arenarum. We characterized all cell types using histological, immuhistochemical, and histochemical methods as well as transmission electron microscopy. Furthermore, we evaluated the organization of the cell types in the gland and anteroposterior variations in the synthesis of the steroids. We found evidence of five cell types: two morphologically different steroidogenic cells, type 1: polyhedral cells tightly attached to each other that have spherical euchromatic nuclei and type 2: retracted cells loosely attached to each other that have oval heterochromatic nuclei. Cell type 2 is mainly observed in the inner zone of the gland. In addition, we observed two types of chromaffin cells, called type 3 and 4 cells, randomly distributed throughout the interrenal gland, as well as type 5 cells, recognized as summer cells. Morphometric analyses of the cell types in the anterior and posterior zones of the interrenal showed that the ratio “area of type 2 cells/total interrenal area” is significantly lower in the posterior zone. In vitro incubations showed that the posterior portion of the gland produces significantly higher amounts of both corticosterone and aldosterone. Overall, our results suggest that the type 2 cells are less active to synthesize both aldosterone and corticosterone, compared to type 1 cells. Unlike most previous reports on the interrenal gland of anurans, in R. arenarum there is a zonation of the steroidogenic cell types, which implies that the organ is not anteroposterior or dorsoventrally homogeneous. © J. Morphol., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
998.
Soili Stenroos Raquel Pino-Bodas Teuvo Ahti 《Cladistics : the international journal of the Willi Hennig Society》2019,35(5):603-603
A new generic name, Rexiella, is published to replace the recently published name Rexia S. Stenroos, Pino-Bodas and Ahti, which turned out to be an illegitimate later homonym of the cyanobacterial genus Rexia D. A. Casamatta, S. R. Gomez and J. R. Johansen. 相似文献
999.
Silvia Sayuri Mandai Raquel Corrêa Buranelli Christoph D. Schubart 《Marine Biology Research》2018,14(6):565-580
The hermit crab Calcinus tibicen has an extensive distribution along the coasts of the western Atlantic Ocean, from the USA to southern Brazil. The present study aimed to test the hypothesis of the presence of phylogeographic structure of C. tibicen throughout its distribution, evaluating the genetic and morphological variabilities of the species. The molecular data, genetic diversity and demographic history were inferred from 16 different localities for the mitochondrial genes cytochrome oxidase subunit I (COI) (75 specimens) and 16S rRNA (20). The morphological information was based on 99 individuals from the same 16 localities. Results were obtained by the construction of haplotype networks and a phylogenetic tree, an Analysis of Molecular Variance (AMOVA), Tajima’s D and Fu’s Fs tests, pairwise mismatch distributions under the sudden expansion model, and by estimating divergence times. The haplotype networks show the existence of two genetically well-defined groups that do not share haplotypes. The phylogenetic tree and the matrix of genetic distances suggest lack of gene between North and South Atlantic groups, also corroborated by AMOVA for the COI gene. The genetic distance can be attributed to at least two ecological factors: the existence of a physiological barrier caused by the Amazon River freshwater plume, and the effect of the bifurcation of the westerly flowing South Atlantic oceanic currents creating a gap along the Brazilian coastline. Demographic history analyses suggest that C. tibicen experienced population expansion, probably after the Amazon River changed its direction. Despite the molecular evidence for the existence of a phylogeographic structure, no morphological pattern for each genetic group was observed. Therefore, based on the described molecular differences and the ecological and historical factors suggested, the question arises whether a cryptic species should be recognized for some of the populations of C. tibicen. 相似文献
1000.
Lindomar A. Lerin Raquel A. Loss Daniela Remonatto Mara Cristina Zenevicz Manuela Balen Vendelino Oenning Netto Jorge L. Ninow Cláudia M. Trentin J. Vladimir Oliveira Débora de Oliveira 《Bioprocess and biosystems engineering》2014,37(12):2381-2394
The named “green chemistry” has been receiving increasing prominence due to its environmentally friendly characteristics. The use of enzymes as catalysts in processes of synthesis to replace the traditional use of chemical catalysts present as main advantage the fact of following the principles of the green chemistry. However, processes of enzymatic nature generally provide lower yields when compared to the conventional chemical processes. Therefore, in the last years, the ultrasound has been extensively used in enzymatic processes, such as the production of esters with desirable characteristics for the pharmaceutical, cosmetics, and food industry, for the hydrolysis and glycerolysis of vegetable oils, production of biodiesel, etc. Several works found in the open literature suggest that the energy released by the ultrasound during the cavitation phenomena can be used to enhance mass transfer (substrate/enzyme), hence increasing the rate of products formation, and also contributing to enhance the enzyme catalytic activity. Furthermore, the ultrasound is considered a “green” technology due to its high efficiency, low instrumental requirement and significant reduction of the processing time in comparison to other techniques. The main goal of this review was to summarize studies available to date regarding the application of ultrasound in enzyme-catalyzed esterification, hydrolysis, glycerolysis and transesterification reactions. 相似文献