Production of Polygalacturonases by Aspergillus section Nigri Strains in a Fixed Bed Reactor

Molecules

Marília Maciel¹  Cristiane Ottoni¹  Cledir Santos¹  Nelson Lima¹  Keila Moreira¹ 

[1] ¹Mycology Department, Federal University of Pernambuco, Cidade Universitária, Recife 50670-420, Pernambuco, Brazil

关键词: Aspergillus niger;    orange peel;    immobilization cells;    polygalacturonases;    fixed bed reactor;   

DOI  :  10.3390/molecules18021660

来源: mdpi

【 摘 要 】

Polygalacturonases (PG) are pectinolytic enzymes that have technological, functional and biological applications in food processing, fruit ripening and plant-fungus interactions, respectively. In the present, a microtitre plate methodology was used for rapid screening of 61 isolates of fungi from Aspergillus section Nigri to assess production of endo- and exo-PG. Studies of scale-up were carried out in a fixed bed reactor operated under different parameters using the best producer strain immobilised in orange peels. Four experiments were conducted under the following conditions: the immobilised cells without aeration; immobilised cells with aeration; immobilised cells with aeration and added pectin; and free cells with aeration. The fermentation was performed for 168 h with removal of sample every 24 h. Aspergillus niger strain URM 5162 showed the highest PG production. The results obtained indicated that the maximum endo- and exo-PG activities (1.18 U·mL⁻¹ and 4.11 U·mL⁻¹, respectively) were obtained when the reactor was operating without aeration. The microtitre plate method is a simple way to screen fungal isolates for PG activity detection. The fixed bed reactor with orange peel support and using A. niger URM 5162 is a promising process for PG production at the industrial level.

【 授权许可】

CC BY   
This is an open access article distributed under the Creative Commons Attribution License (CC BY) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.