Effects of different carbon sources on the synthesis of pectinase by Aspergillus niger in submerged and solid state fermentations

Abstract

A study was made to compare the production of pectinase by Aspergillus niger CH4 in solid-state (SSF) and submerged (SmF) fermentations. Production of endo-(endo-p) and exo-pectinase (exo-p) by SSF was not reduced when glucose, sucrose or galacturonic acid (up to 10%0) were added to a culture medium containing pectin. Moreover, both activities increased when concentrations of the carbon sources were also increased. In SmF, these activities were strongly decreased when glucose or sucrose (3%) was added to culture medium containing pectin. The addition of galacturonic acid affected endo-p activity production to a lesser extend than exo-p. Final endo-p and exo-p activities in SSF were three and 11 times higher, respectively, than those obtained in SmF. The overall productivities of SSF were 18.8 and 4.9 times higher for endo-p and exo-p, respectively, than those in SmF. These results indicate that regulatory phenomena, such as induction-repression or activation-inhibition, related to pectinase synthesis by A. niger CH4 are different in the two types of fermentation.

Screening of bacterial strains for pectinolytic activity: characterization of the polygalacturonase produced by Bacillus sp

“…Activities of PG produced by Bacillus sp strains were higher than those produced by Aspergillus niger (19), Aspergillus sp and A. niger ATCC20107 (16), Aureobasidium pullulans (10) and Tubercularia vulgaris (12). However, they were lower than those reported using Bacillus GK-8 (9).…”

Influence of pectin, glucose, and pH on the production of endo- and exo-polygalacturonase by Aspergillus oryzae in liquid medium

“…The spores used to inoculate the cultivation medium were enumerated by direct counting using a Neubauer chamber as previously described by Solis-Pereyra et al (1993). The A. oryzae concentration, in grams of dry mass per liter, was gravimetrically determined by filtering a known volume of culture medium through 0.45-µm-poresize cellulose membranes (MILLIPORE, USA) and drying at 90 °C for 24 h.…”

“…Similar results were published by Teixeira et al (2000), who described a repression of endo-and exo-PG production in Aspergillus japonicus when concentrations of glucose, pectin and sucrose were above certain levels. Solis-Pereyra et al (1993) and Acuña-Arguelles et al (1995) also reported that an excess of glucose in solid media reduced the formation of pectinases by Aspergillus niger. These authors claim that this result was due to a strong drop in the pH of the medium rather than catabolic repression or growth inhibition.…”

Column bioreactor use for optimization of pectinase production in solid substrate cultivation

“…Pectinase synthesis occurs in many microbial groups, however, for the industrial pectinase production, fungi are the most used group due to their high enzymatic excretion capacity (23). Pectinolytic enzyme synthesis is highly influenced by substratum, particularly, carbon and nitrogen sources (6), presence of pectin (24) and temperature (3). Santos et al (22) reported that the aeration rate affects the substratum temperature and recommend controlling it to avoid overheating and enzyme denaturation during SSC.…”