Utilização de Resíduos Agro-Industriais em Processos Biotecnológicos como Perspectiva de Redução do Impacto Ambiental

The increasing concern about the environment has been mobilizing some market segments. Several governmental bodies and industries are preparing to apply an environment policy that diminishes the negative impacts to the nature. The industrial residue, after being generated, needs an adjusted destination, since, beyond creating potential environment problems, the residues represent losses of raw materials and energy, demanding significant investments in the pollution controlling treatments. The food industry produces a series of residues of high value of (re)utilization. Many works study the residues bioutilization such as the crushed sugar cane for protein enrichment of animal ration. In this work it will be presented a study of a possible usage of the crushed sugar cane for the production of Spirulina with satisfactory protein increment results when compared with other results gotten in literature.The increasing concern about the environment has been mobilizing some market segments. Several governmental bodies and industries are preparing to apply an environment policy that diminishes the negative impacts to the nature. The industrial residue, after being generated, needs an adjusted destination, since, beyond creating potential environment problems, the residues represent losses of raw materials and energy, demanding significant investments in the pollution controlling treatments. The food industry produces a series of residues of high value of (re)utilization. Many works study the residues bioutilization such as the crushed sugar cane for protein enrichment of animal ration. In this work it will be presented a study of a possible usage of the crushed sugar cane for the production of Spirulina with satisfactory protein increment results when compared with other results gotten in literature.A crescente preocupação com o meio ambiente vem mobilizando vários segmentos do mercado. Inúmeros órgãos governamentais e indústrias estão se preparando para aplicar uma política ambiental que diminua os impactos negativos à natureza. O resíduo industrial, depois de gerado, necessita de destino adequado, pois, além de criar potenciais problemas ambientais, os resíduos representam perdas de matérias-primas e energia, exigindo investimentos significativos em tratamentos para controlar a poluição. A indústria de alimentos produz uma série de resíduos de alto valor de (re)utilização. Muitos trabalhos estudam a bioutilização de resíduos tais como o bagaço de cana-de-açúcar para enriquecimento protéico de ração animal. Neste trabalho será apresentado um estudo sobre a possível utilização do bagaço de cana-de-açúcar para produção de Spirulina com resultados de incremento protéico bastantes satisfatórios quando comparados com outros resultados obtidos na literatura

Spirulina platensis growth estimation by pH determination at different cultivations conditions

Spirulina platensis is a cyanobacterium that has a high protein content and therefore, a high nutritional value. It can be cultivated either in a liquid or in a solid culture. When cultivated in aqueous culture the cell growth can be determined by following the optical density. On the other hand, when produced by solid cultivation the growth can be determined only indirectly, such as, through determination of the protein content of the fermenting solids. In this work the possibility of estimating cell growth by pH determination was verified. From the results it was concluded that pH and protein production (solid or surface culture) or cell content (liquid culture) correlate well, therefore pH determination seems to be a good method to determine cell growth

Protein production by Arthrospira (Spirulina) platensis in solid state cultivation using sugarcane bagasse as support

The genus Arthrospira comprises a group of filamentous multicellular cyanobacteria and can be used for animal feed and human food. Solid state fermentation or cultivation (SSF) involves the use of a culture medium composed of solid material with given moisture content. No studies have been published about the cultivation of microalgae or cyanobacteria on solid medium. Furthermore, although sugar-cane bagasse is used as source of energy in alcohol distilleries in Brazil, the excess could be a support to photosynthetic microorganism growth. The experimental design methodology was used to evaluate the protein production by Arthrospira platensis under SSF using sugarcane bagasse as support, taking into account the moisture content of the medium, light intensity and inoculum concentration. Moisture was found to have a strong influence on the performance of the process. The best conditions were: moisture of 98.8%; inoculum concentration of 0.15 g biomass·kg wet culture medium−1 and light intensity of 6.0 klx

SHORT COMMUNICATION - Spirulina platensis growth estimation by pH determination at different cultivations conditions

Spirulina platensis   is a cyanobacterium that has a high protein content and therefore, a high nutritional value. It can be cultivated either in a liquid or in a solid culture. When cultivated in aqueous culture the cell growth can be determined by following the optical density. On the other hand, when produced by solid cultivation the growth can be determined only indirectly, such as, through determination of the protein content of the fermenting solids. In this work the possibility of estimating cell growth by pH determination was verified. From the results it was concluded that pH and protein production (solid or surface culture) or cell content (liquid culture) correlate well, therefore pH determination seems to be a good method to determine cell growth

Use of volatile fatty acids salts in the production of xanthan gum

Background: The aim of this study was the production of xanthan gum from salts of volatile fatty acids, which can be generated in anaerobic processes for the production of hydrogen from organic wastewaters. Xanthan gum was produced with three different acid salts used to replace the traditional citrate, which is normally used in the culture for the production of this biopolymer. The volatile fatty acids (VFA) salts used were sodium acetate 0.0328 M, sodium propionate 0.0219 M, and sodium butyrate 0.0164 M. Results: The values of biomass yield, (Yp/x) obtained were 9.2 g/g for acetate, 11.78 g/g for citrate, 11.80 g/g for butyrate and 14.59 g/g for propionate, while the values of the product yield (Yp/s), were 0.92; 0.59; 0.71 and 0.72 for acetate, citrate, butyrate and propionate. As for the rheological characterization, the gums produced showed a consistency index (K) and flow index (n) of 9.8 dina.s-n.cm-2 and 0.34 for acetate; 6.3 dina.s-n.cm-2 and 0.39 for citrate, 5.8 dina.s-n.cm-2 and 0.45 for butyrate, 39.2 dina.s-n.cm-2 and 0.24 for propionate, that characterize the gums with good consistency and fluidity. Conclusions: It is possible to produce xanthan gum from short-chain volatile acids in replacement by the citrate that is usually used in medium composition for the gum production. These results contribute to the feasibility studies for implementation of processes for treating wastewater generating products such as volatile acids, hydrogen and consequent use of these acids for the production of xanthan gum

Solid-state fermentation of Bacillus thuringiensis tolworthi to control fall armyworm in maize

The well-known entomopathogenic bacterium Bacillus thuringiensis (Bt) produces a spore-crystal complex which is responsible for its biocide characteristic, and the bacterium can be obtained by fermentation, either in liquid or semi-solid substrates. This paper presents a successful way to achieve solid-state fermentation of active Bt var. tolworthi (Btt) against Spodoptera frugiperda (fall armyworm) in corn. More than 109 CFU/g were obtained using humidified rice as substrate maintained in polypropylene bags. This active complex (substrate plus spore-crystal of Bt) was prepared in order to obtain 2 x 106 spores/mL; the final suspension then sprayed via tractor on corn fields. On the treated plants, mortality of neonate larvae was 100% within two days of spraying, and all larvae were found dead on leaves. During one maize crop cycle, two applications were made, and up until 70 days after emergence it was not necessary to apply any other insecticide for fall armyworm control