Red Pigment Production By Monascus Purpureus In Stirred-Drum Bioreactor

Mohamad Al Aamin Razali,Farhan M Said

doi:10.26480/gws.01.2017.13.15

Abstract

Several studies has been conducted to economically cultivate the Monascus sp. However, the potential of using stirred drum bioreactor in solid state fermentation (SSF) for Monascus sp. cultivation has been relatively understudied. Oil palm frond (OPF) petiole has been used as a potential substrate due to its nutritional contents and to add more value to local agricultural waste. This study reports the production of red pigment by Monascus purpureus FTC 5357 in a 2.3 L bench top - stirred-drum bioreactor. The fungus was grown on moistened OPF substrate (60 % (w/w)) supplemented with 2% (w/w) of soy meal peptone. The effects of different aeration rates (0.3-1.0 vvm of humidified air), agitation programme (4-8 cycles per day), and substrate load capacity (25-40 % (v/v) of total drum capacity) on red pigment production are reported. Aeration rate showed a positively correlated interaction to red pigment production in which the highest red pigment were produced using1.0 vvm (6.09 AU/g dry solid), and non-aerated culture showed the lowest red pigment production (0.81 AU/g dry solid). The agitation programme was also showing the positive trend of interaction, in which 8 cycles per day showed the highest red pigment production (4.34 AU/g dry solid) and 4 cycles per day agitation showed the lowest red pigment production.The red pigment production was peaked at 30% (v/v) drum loading capacity (5.61 AU/g dry solid) and the lowest at 25% (v/v) (0.89 AU/g dry solid), whereas 40% (v/v) substrate capacity was incapable of being mixed due to low power output of agitating motor. Results suggested that OPF was a potent source of substrate for the cultivating Monascus purpureus using SSF and all 3 factors (aeration, substrate load capacity and agitation programme) were significantly influenced the red pigment production.

Highlights

Most of the manufactured food will be introduced to colorant to enhance the attractiveness of the product
EXPERIMENTAL In this study, a fabricated bioreactor from the Faculty of Chemical and Natural Resources Engineering (FKKSA) laboratory, UMP, was used (Figure 1). This bioreactor consists of (1) 2.3 L stainless steel drum mounted with a self-modified impeller and a direct current-geared motor with a metal heatingjacket at the bottom of the drum, (2) a control panel for agitation and Monascus purpureus strain FTC 5357 stock culture was maintained on Potato Dextrose Agar (PDA) and incubated in the dark at 30oC for 7-8 days, which was preserved at 4oC
Series of experiments had been conducted to study the effect of aeration rate, agitation and loading capacity of the drum to red pigment production by Monascus purpureus strain FTC 5357 in a stirred drum bioreactor.All of conducted experiment were subjected to initial moisture content of 60% (w/w) of substrate supplemented with peptone (2%, w/w), 0.5 vvm of humidified air, loading capacity of 30% (v/v) and were agitated for 6 rotations/ day in the dark at room temperature in 8 days, unless otherwise mentioned

Summary

INTRODUCTION

Most of the manufactured food will be introduced to colorant to enhance the attractiveness of the product. One of the microorganism with high potential for large scale natural pigment production is Monascus sp., due to its ability to produce an intense red pigment as well as other beneficiary metabolic by-products (e.g. lovastatin, antioxidants) [3][4][5]. In this regard, the use of bioreactors are advantageous because of its potential to process significantly larger scale of substrate with the aid of parameters control system. This study has been focused on the SSF of Monascus purpureus using OPF as a potential source of substrate in stirred-drum bioreactor, for the purpose of red pigment production

EXPERIMENTAL

RESULTS AND DISCUSSION

CONCLUSION