L-Asparaginase Production using Solid-state Fermentation by an Endophytic Talaromyces pinophilus Isolated from Rhizomes of Curcuma amada

Abstract

In recent times, exploration of endophytes for L-asparaginase production is gradually gaining momentum. This work deals with studies on the production of L-asparaginase from Talaromyces pinophilus, an endophytic fungus isolated from the rhizomes of Curcuma amada. L-asparaginase production was carried out by Submerged Fermentation (SmF) followed by Solid-state Fermentation (SSF). A liquid medium was designed and optimized using Plackett-Burman Design and Response Surface Methodology (RSM), under SmF. Additionally, optimal concentrations of various metal salts were incorporated in the optimized liquid medium, by one-factor-at-a-time experiments. To further enhance L-asparaginase production, SSF was carried out using Polyurethane Foam (PUF) as inert support impregnated with the optimized liquid medium. Effects of PUF cube volume, mass of PUF, moisture content, initial medium pH, and incubation temperature on the enzyme production in SSF were optimized by one-factor-at-a-time approach.L-asparaginase production enhanced from 80.8 U/mL in the unoptimized medium to 94.4 U/mL in the optimized medium under SmF. Enzyme production further increased to 120.3 U/mL under SSF by using PUF soaked in the optimized liquid medium. This study highlights the benefits of carrying out SSF with PUF, using the same liquid medium optimized for SmF-a novel approach to enhance the enzyme yield (in our case an increase of about 27% was observed). To the best of our knowledge, this is the first report on the production of L-asparaginase by both SmF and SSF, from an endophyte Talaromyces pinophilus isolated from the rhizomes of Curcuma amada.