Orthogonal Array Approach for Optimization of Carrageenase Production by Solid State Fermentation of Pseudomonas aeruginosa ZSL-2

Ziayoddin M

doi:10.4172/1948-5948.1000078

Abstract

The optimization of solid-substrate medium and fermentation conditions for the production of enzyme carrageenase by a Pseudomonas aeruginosa ZSL-2 was achieved for the first time by employing an orthogonal array testing strategy (OATS). Of the four different substrates tested, wheat bran showed maximum production of carrageenase enzyme. The factors that influence the solid-substrate fermentation (SSF) conditions such as, moisture content, moistening agent, temperature, pH, inoculum size, additional carbon source and the fermentation period for the production of enzyme were studied by one-factor at a time and also by L9(34) an orthogonal array method. The maximal production of k-carragenase (7.44 U/g) dry bacterial bran was achieved at moisture level 1:2.5 (w/v; wheat bran to moisture level), moistening agent IV, inoculum size (10%), temperature 37°C and 48 h of fermentation. The effects of various parameters like medium, inoculum size, temperature, moistening agent, moisture level, incubation period, and supplementation of other carbon sources on the production of carrageenase by SSF using OATS is investigated and the results are presented and discussed.

Highlights

The submerged fermentation (SmF) has been used traditionally for the production of industrially important enzymes as it allows greater control of environmental factors such as, temperature, pH, oxygen supply, ease of handling and study the rheology of the culture medium but, it demands expensive instrument, medium and the cumbersome downstream purification of product due to very high volume
In light of the numerous advantages of substrate fermentation (SSF) over SmF, the production of enzyme carrageenase by a P. aeruginosa ZSL-2 was attempted by SSF using various naturally occurring agricultural raw materials as substrates
Of the four natural solid-substrates tested for SSF (Figure 1) wheat bran was found to support maximum production of carrageenase by the bacterium as it is compared to wheat straw (WS), gram bran (GB) and paddy straw (PS)

Summary

Introduction

The submerged fermentation (SmF) has been used traditionally for the production of industrially important enzymes as it allows greater control of environmental factors such as, temperature, pH, oxygen supply, ease of handling and study the rheology of the culture medium but, it demands expensive instrument, medium and the cumbersome downstream purification of product due to very high volume. SSF is preferred to SmF for it shows high production of better quality product, simple and environmental friendly process, low capital investment, low levels of repression [5] and most importantly it makes use of cheap and inexpensive agricultural wastes or by-products for the production of high value products [4,6,7,8]. SSF process are usually simpler, that uses inexpensive raw materials like by-products of food-processing and agricultural industry as substrates, such as, gram bran, wheat bran, rice bran, banana waste, sugarcane bagasse, defatted soybean cake, groundnut cake etc, for the production of various enzymes by different microorganisms [15,16,17]

Methods

Results

Conclusion