Biological flocculants are advantageous due to their biodegradability and safety to living beings. In this work, four bacterial strains, isolated from sugarcane cropped soil (Bacillus megaterium LBPMA-APFSG3Isox and B. toyonensis LBPMA-ACOPR1.Isox) and sludge of an agroindustrial effluent (B. pumilus LBPMA-BLD07 and B. thuringiensis LBPMA-EFIII), were studied. It was found that all of them secreted bioflocculants, at 37 ± 1 °C, with no pH changes over time and the flocculant activity increased during the time course of incubation. These results stimulated the optimization of the culture conditions to improve flocculation rates, such as the pH, nitrogen sources and carbon. For B. toyonensis LBPMA-ACOPR1.Isox and B. thuringiensis LBPMA-EFIII, the best pH for the bioflocculant production was 5.0. Sucrose and maltose were the best sources of carbon, while urea was the preferred source of nitrogen for two of the tested isolates (B. pumilus LBPMA-BLD07 and B. toyonensis LBPMA-ACOPR1.Isox), followed by (NH 4)2SO 4 (B. megaterium LBPMA-APFSG3Isox) and peptone (B. thuringiensis LBPMA-EFIII). The FTIR-ATR spectra of each extracted material responsible for the flocculant activities of the strains displayed carboxyl, hydroxyl and methoxy functional groups characteristic of polysaccharides.
Shrimps fishing, especially the pink (Farfantepenaeus brasiliensis and F. subtilis) and the white (Litopenaeus schmitti) ones, are relevant for the Brazilian Northeast economy, and their price depends on their aspect-quality. They are rich in lipids/proteins, which are a target for autolytic and microbial enzymes. These may not change the shrimps' appearance but generate substances that may cause poisoning, as histamines. This work compared the microbial quality of fillets and shells of these three shrimps, harvested in two years, after cooking and storage under different freezing times (0-90 days), as well as the total carotenoids (TC) and antioxidant activity (AA%) of ethanolic extracts from all the samples, using spectrophotometry and DPPH test. None histaminogenic and few mesophilic bacteria were isolated (all Gram+ species of Corynebacterium, Listeria, Arthrobacter, Bacillus and Erysipelothrix), but in lower number than the tolerability limit. The TC and AA% of fresh shells from time "zero" were always higher than those of fillets, mainly for F. subtilis. Cooking increased TC and AA% of fillets, but reduced them in shells, and both parameters declined along the freezing. Thin-layer chromatography and spectrophotometric scanning of all the extracts and standards evidenced astaxanthin as the main carotenoid.
modalidades praticadas em conformidade com as realidades locais das comunidades alvo, a intervenção da proposta, listaremos indicativos das espécies e posicionamento adequado para a formação dos sistemas, as formas de realização de diagóstico rápido e participativo, a forma de elaboração do arranjo ou desenho de SAF. Como resultados foi possível concluir que a recuperação de áreas degradadas requer profundo conhecimento local do lugar a ser intervisto, compreensão da cultura, dos dizeres e fazeres locais, e entendimento de que a efetividade só é alcançada quando a recuperação e o uso responsável ocupa um lugar de privilégio e importância na vida da comunidade de forma orgânica. Foi possível inferir que os SAFs proporcionam aumento da biodiversidade, regulação de ciclo hidrológico, controle erosivo, do assoreamento e ciclagem de nutrientes.
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