Utilization of palm kernel cake for production of β-mannanase by Aspergillus niger FTCC 5003 in solid substrate fermentation using an aerated column bioreactor

Abstract

The production of beta-mannanase from palm kernel cake (PKC) as a substrate in solid substrate fermentation (SSF) was studied using a laboratory column bioreactor. The simultaneous effects of three independent variables, namely incubation temperature, initial moisture content of substrate and airflow rate, on beta-mannanase production were evaluated by response surface methodology (RSM) on the basis of a central composite face-centered (CCF) design. Eighteen trials were conducted in which Aspergillus niger FTCC 5003 was cultivated on PKC in an aerated column bioreactor for seven days under SSF process. The highest level of beta-mannanase (2117.89 U/g) was obtained when SSF process was performed at incubation temperature, initial moisture level and aeration rate of 32.5 degrees C, 60% and 0.5 l/min, respectively. Statistical analysis revealed that the quadratic terms of incubation temperature and initial moisture content had significant effects on the production of beta-mannanase (P < 0.01). A similar analysis also demonstrated that the linear effect of initial moisture level and an interaction effect between the initial moisture content and aeration rate significantly influenced the production of beta-mannanase (P < 0.01). The statistical model suggested that the optimal conditions for attaining the highest level of beta-mannanase were incubation temperature of 32 degrees C, initial moisture level of 59% and aeration rate of 0.5 l/min. A beta-mannanase yield of 2231.26 U/g was obtained when SSF process was carried out under the optimal conditions described above.

Experimental design of response surface methodology used for utilisation of palm kernel cake as solid substrate for optimised production of fungal mannanase

“…Henceforth PKC was used for mannanase production in further studies. Recent, reports suggest use of PKC in mannanase production by mesophilic fungi (Abdeshanian et al 2010; Rashid et al 2011; Soni et al 2015). However, to date there has been no report of β-mannanase production on PKC by any thermophilic fungi.…”

“…The average cost of PKC has been estimated to be about 0.093/kg in 2015 (MPOB, 2015; Azman et al 2016). Abdeshanian et al (2010) and Soni et al (2015) used PKC as a solid substrate in SSF for production of β-mannanase using mesophilic fungi Aspergillus sp. & A. terreus , respectively.…”

Optimization of Multi-enzyme Production by Fungi Isolated from Palm Kernel Expeller using Response Surface Methodology

“…Though several fungal strains have been isolated and characterized for the production of enzyme (Abdeshahian et al, 2010;Abdeshahian et al, 2011;Coman and Bahrim, 2011), study on the co-production of enzymes specifically for hydrolysis of PKE using PKE as the sole substrate is limited. Through optimization,19.97,44.12,and 262.01 U/g of endoglucanase, mannanase, and xylanase activity were obtained.…”

“…A second-order model like the central composite design (CCD) is widely used in RSM, because it can take on a wide variety of functional forms, and this flexibility allows it to predict the true response surface more closely. This approach has been successfully employed to maximize production of enzyme in SSF (Abdeshahian et al 2010;Abdeshahian et al 2011;Coman and Bahrim 2011). However, most of the above studies focused on the optimization of single enzyme production.…”

β-Mannanase Production by Aspergillus flavus in Solid-State Fermentation of Palm Kernel Cake

“…Comparison on b-mannanase production between this study and other works on SSF of PKC; published works are limited and focused on Aspergillus niger in flasks SSF (Ong et al 2004) and SSF in a packed bed with axial flow of humidified air (Abdeshahian et al 2010). A. niger produced considerably higher enzyme at lower moisture level.…”