Optimization of D-Amino Acid Oxidase Production by Trigonopsis variabilis Using Glucose Syrup from Cassava as Carbon Source

Ahmad Wibisana,Herman Suryadi,Zaldy Rusli

doi:10.4172/2155-6199.1000445

Abstract

Rusli Z, Suryadi H, Wibisana A. 2018. Optimization of D-amino acid oxidase production by Trigonopsis variabilis using glucose syrup from cassava as carbon source. Bioteknologi 15: xxxx. Glucose syrup from cassava (GSC) contains glucose as the main sugar suitable for an economical and efficient production of D-amino acid oxidase (DAAO) by Trigonopsis variabilis. The aim of this study is to optimize the DAAO production by T. variabilis using GSC as the carbon source via response surface methodology (RSM) with Face-centered Central Composite Design (FCCD). In the first step, the effects of six factors (concentration of GSC and DL-alanine, pH, temperature, incubation time, and inoculum concentration) were screened to obtain the significant factors on DAAO production by Plackett-Burman design. As a result, the incubation time, the concentration of GSC and DL-alanine showed to be significant factors for DAAO production (P<0.05). These factors were then optimized using RSM with FCCD. The optimized RSM results demonstrated that a quadratic polynomial model was found suitable to define the relation between the incubation times, concentration of GSC and DL-alanine parameters. Moreover, the observed high R2 value (0.9782) confirms a strong evaluation of the experimental data. The optimum condition for DAAO production is as follows: GSC and DL-alanine concentration was 12.3% and 0.3%, respectively, and the culture incubation time was 56.1 hours. Using this condition, we got a DAAO activity of 195.38 U/g dry weight of yeast.

Highlights

The production of pure chiral compounds via costeffective method has become an important approach to fine chemical, agrochemical and pharmaceutical industries
The aim of this study is to optimize the production of D-amino acid oxidase (DAAO) by T. variabilis using Glucose syrup from cassava (GSC) as carbon source
Screening by Plackett-Burman design Plackett-Burman design was used to identify the important parameters for DAAO production

Summary

Introduction

The production of pure chiral compounds via costeffective method has become an important approach to fine chemical, agrochemical and pharmaceutical industries. The use of biocatalysts for the production of pure chiral compounds has been widely applied in large scale and becoming a cost-effective approach. The recent development of biocatalysts processes was designed to be employed on a large-scale and to produce inexpensive enzyme with good properties, i.e., high activity, stability and selectivity (Caligiuri et al 2006). Deracemization of a DL-mixture to obtain L-isomer can be done by employing a D-amino acid oxidase (DAAO, EC 1.4.3.3) and non-selective chemical reduction step to obtain enantiopure L-amino acid after numerous cycles (Turner 2004). DAAO catalyzes the oxidative deamination of D-amino acids to produce α-keto and ammonia

Objectives

Methods

Results