Optimized production of phytase by solid-state fermentation using triticale as substrate and source of inducer

Abstract

This study was carried out to evaluate the process of phytase production by Aspergillus niger in solidstate fermentation (SSF) using triticale waste. A waste that currently has no use was reported for this biotechnological process, and is of high impact due to the null use. The process was carried out using an additive free medium, supplemented with only one nitrogen source. Under these conditions, phytase activity of 7.45 U/g dry substrate (DS) was obtained. The process was optimized using different additives such as dextrose, lactose, Tween 80 and potassium chloride. For fermentation maximization, two experimental designs were used: 1) Plackett-Burman design (PBD) and 2) the Box-Behnken design (BBD). PBD was used to evaluate the effect of related variables on the production of phytase, as well as their level of significance in the process, while BBD was used for optimal conditions determination. The process was conducted with Petri dishes and a maximum enzyme activity of 25.8 IU/g DS was obtained. Subsequently, SSF was carried out in a tray to increase the amount of fermented substrate and phytase activity of 23.63 IU/g DS was obtained. The results of this study suggest a minimal decrease (8.4%) in enzyme production with scaling.

Bioprocess for Production, Characteristics, and Biotechnological Applications of Fungal Phytases

“…For example, Sabu et al (2002) have reported on phytase production by R. oligosporus on coconut oil cake substrate in SSF. In a recent study, triticale waste was used as a substrate for the evaluation of phytase production by A. niger (Neira-Vielma et al, 2018). Additionally, phytase production was investigated by SSF using mixed substrates.…”

“…Phytase production using different fungal strains is affected by differing culture conditions (Qasim et al, 2017;Neira-Vielma et al, 2018). Optimum conditions for the production of phytases obtained from different fungal strains have been established by changing both nutrient and physical conditions.…”

“…However, the thermostability of phytases is also essential for their use in animal feed (Dersjant-Li et al, 2015). Fungal phytases are active in the optimum temperature range of 37-67 • C. Various studies have reported that different fungal phytases are active under different optimal conditions with regard to pH and temperature (Lassen et al, 2001;Zhu et al, 2011;Neira-Vielma et al, 2018). Fungal phytase obtained from A. niger van Tieghem showed a high degree of specific activity under an optimal temperature range of 52-55 • C together with an optimal pH value of 2.5 (Vats and Banerjee, 2005).…”