Monitoramento ambiental do herbicida clomazone, formulação solúvel, em águas de lavouras de arroz irrigado.

bitstream/item/30273/1/boletim-30.pd

Metodologia para obtenção de fungos degradadores do herbicida glifosato.

bitstream/item/44540/1/documento-308.pd

Medium- and short-chain dehydrogenase/reductase gene and protein families: The MDR superfamily

The MDR superfamily with ~350-residue subunits contains the classical liver alcohol dehydrogenase (ADH), quinone reductase, leukotriene B4 dehydrogenase and many more forms. ADH is a dimeric zinc metalloprotein and occurs as five different classes in humans, resulting from gene duplications during vertebrate evolution, the first one traced to ~500 MYA (million years ago) from an ancestral formaldehyde dehydrogenase line. Like many duplications at that time, it correlates with enzymogenesis of new activities, contributing to conditions for emergence of vertebrate land life from osseous fish. The speed of changes correlates with function, as do differential evolutionary patterns in separate segments. Subsequent recognitions now define at least 40 human MDR members in the Uniprot database (corresponding to 25 genes when excluding close homologues), and in all species at least 10888 entries. Overall, variability is large, but like for many dehydrogenases, subdivided into constant and variable forms, corresponding to household and emerging enzyme activities, respectively. This review covers basic facts and describes eight large MDR families and nine smaller families. Combined, they have specific substrates in metabolic pathways, some with wide substrate specificity, and several with little known functions

Influência do sistema de produção e do armazenamento refrigerado nas características físico-químicas e no desenvolvimento de compostos voláteis em morangos.

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Peat, Rice Husk and Rice Husk Carbon as Low-Cost Adsorbents for Metals from Acidic Aqueous Solutions

<div><p>We assessed the abilities of rice husk (RH), rice husk carbon (RHC), and peat to adsorb Cr, Fe, Mn, Ni, Zn, and Pb from aqueous solutions compared with commercial activated carbon (AC). The sorbent capacities were evaluated by percolation of aqueous solutions containing these six metals through adsorbent columns. Metal concentration was monitored by total reflection X-ray fluorescence (TXRF). Initial metal concentrations added to the columns were between 25 and 50 mg L⁻¹, while those in the treated effluent ranged from 0.004 to 0.96 mg L⁻¹. The adsorption capacities of the sorbents for these metals were examined by non-linear Langmuir and Freundlich models. The maximum adsorptive capacities expressed as individual metal (<i>q</i>_<i>m</i>) sums were 67.7, 86.9, 80, and 44.6 mg g⁻¹ for AC, RHC, peat, and RH, respectively. The resulting isotherm parameters were used to compare the performance of the sorbents and to determine the ΔG values. After percolation through the adsorbent columns, the ecotoxicity of the eluates were determined with the probe Daphnia magna. Effluents from the rice husk sorbent column exhibited the lowest toxicity. Supplemental materials are available for this article. Go to the publisher's online edition of <i>Separation Science & Technology</i> to view the supplemental file.</p> </div