Phytase Production by Rhizopus microsporus var. microsporus Biofilm: Characterization of Enzymatic Activity After Spray Drying in Presence of Carbohydrates and Nonconventional Adjuvants

Abstract

Microbial phytases are enzymes with biotechnological interest for the feed industry. In this article, the effect of spray-drying conditions on the stability and activity of extracellular phytase produced by R. microsporus var. microsporus biofilm is described. The phytase was spray-dried in the presence of starch, corn meal (>150 μm), soy bean meal (SB), corn meal (<150 μm) (CM), and maltodextrin as drying adjuvants. The residual enzyme activity after drying ranged from 10.7% to 60.4%, with SB and CM standing out as stabilizing agents. Water concentration and residual enzyme activity were determined in obtained powders as a function of the drying condition. When exposed to different pH values, the SB and CM products were stable, with residual activity above 50% in the pH range from 4.5 to 8.5 for 60 min. The use of CM as drying adjuvant promoted the best retention of enzymatic activity compared with SB. Spray drying of the R. microsporus var. microsporus phytase using different drying adjuvants showed interesting results, being quite feasible with regards their biotechnological applications, especially for poultry diets.

Production and Partial Characterization of an Extracellular Phytase Produced by &lt;i&gt;Muscodor&lt;/i&gt; sp. under Submerged Fermentation

“…The microorganism Mucor racemosus NRRL 1994 produced phytase using wheat bran as substrate/support [23]. Other additional complex carbon sources as crushed soy, as well as some saccharides as sucrose, glucose, fructose, galactose also have been investigated for phytase production [13]. The use of alternative carbon sources for phytase production can reduces the cost of process, allowing the obtainment of a cheap product.…”

“…In each experiment we included inactivated enzyme controls to estimate the non-enzymatic hydrolysis of substrate. One unit of phytase activity was defined as the amount of phytase required to release one µmol of inorganic phosphorus (Pi) per minute under test conditions [13].…”

“…The production by filamentous fungi has been described in Penicillium oxalicum PJ3, Schizophyllum commune, Rhizopus oryzae, Aspergillus ficcum and Rhizopus microspores var. microsporus [9]- [13]. Many studies are focused in the production and characterization of phytase from some microorganisms, but information concerning enzyme characteristics as regulation, catalytic capacity, specificity and optimization of production, still need to be clarified to reduce costs and to facilitate the use of this enzyme under an industrial scale.…”

Secagem Por Spray-Drying De Fitases E Xilanases Produzidas Por Fungos Filamentosos Em Cultivo Em Estado Sólido

“…Concentrações próximas à encontrada no presente trabalho são reportadas na literatura como adequadas. Sato et al (2013) obteve melhores resultados em ensaio discriminativo de adjuvantes para a secagem de fitases com 10% de farelo de soja. Para Anandharamakrishnan, Rielly e Stapley, (2007) alta concentração de sólidos da suspensão dá origem a uma crosta mais espessa na superfície da partícula que, associado à altas temperaturas do gás de secagem e elevadas taxas de alimentação, resulta na formação rápida de uma massa seca, enquanto o interior ainda está úmido, favorecendo assim a desnaturação das proteínas.…”

“…Encontra-se na literatura a aplicação de diversos aditivos como maltodextrina, açúcares (celobiose, glicose, lactose, sucrose e trealose), polímeros (carboximetilcelulose, celulose microcristalina, dextrana e goma arábica) e polióis (glicerol, manitol, propileno glicol, sorbitol e xilitol) (BELGHITH, CHAABOUNI e GARGOURI, 2001;DePAZ et al 2002;SELIVANOV, 2005;NAMALDI, ÇALIK e ULUDAG, 2006;DOMINGUES et al 2008;SLOTH et al 2009;COSTA-SILVA, 2010). Sato et al (2013) Para a determinação da atividade das fitases foi empregado o método de Heinonen e Lahti (1981), para o qual uma unidade de atividade enzimática é definida como a quantidade de enzimas necessárias para liberar 1 µmol de fosfato inorgânico por minuto de reação nas condições do ensaio.…”