Xylanase production by Aspergillus awamori under solid state fermentation conditions on tomato pomace
Braz. j. microbiol
; 42(4): 1585-1597, Oct.-Dec. 2011. ilus, graf, tab
Article
en En
| LILACS
| ID: lil-614625
Biblioteca responsable:
BR32.1
ABSTRACT
In this work, tomato pomace, a waste abundantly available in the Mediterranean and other temperate climates agro-food industries, has been used as raw material for the production of some hydrolytic enzymes, including xylanase, exo-polygalacturonase (exo-PG), cellulase (CMCase) and ¥á-amylase. The principal step of the process is the solid state fermentation (SSF) of this residue by Aspergillus awamori. In several laboratory experiments, maximum xylanase and exo-PG activities were measured during the first days of culture, reaching values around 100 and 80 IU/gds (international units of enzyme activity per gram of dried solid), respectively. For CMCase and ¥á-amylase production remained almost constant along fermentation, with average values of 19 and 21.5 IU/gds, respectively. Experiments carried out in a plate-type bioreactor at lab scale showed a clear positive effect of aeration on xylanase and CMCase, while the opposite was observed for exo-PG and ¥á-amylase. In general, xylanase was the enzyme produced in higher levels, thus the optimum conditions for the determination of the enzyme activity was characterized. The xylanase activity shows an optimum pH of 5 and an optimum temperature of 50 ¨¬C. The enzyme is activated by Mg2+, but strongly inhibited by Hg2+ and Cu2+. The enzymatic activity remains quite high if the extract is preserved in a range of pH from 3 to 10 and a temperature between 30 ¨¬C to 40 ¨¬C.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
LILACS
Asunto principal:
Aspergillus
/
Xilanos
/
Estructuras de las Plantas
/
Activadores de Enzimas
Idioma:
En
Revista:
Braz. j. microbiol
Asunto de la revista:
MICROBIOLOGIA
Año:
2011
Tipo del documento:
Article
País de afiliación:
Brasil
/
España
Pais de publicación:
Brasil