Effect of submerged culture conditions on exopolysaccharides production by Armillaria luteo-virens Sacc QH and kinetic modeling

Abstract

This work aimed to develop the submerged cultivation conditions for improved exopolysaccharides (EPS) production by Armillaria luteo-virens Sacc. The effects of culture temperature, aeration rate, inoculum level, initial pH, and additives on EPS formation and mycelial growth are investigated. The aeration rate, initial pH, and inoculum level significantly affected EPS production under the submerged cultivation. The developed conditions were as follows: cultivation temperature 23 °C, initial pH 5.0, aeration rate 0.5 vvm, 0.5% Tween 80, inoculum level 5% (v/v), and shaking speed 120 r/min. Under the developed conditions, the highest EPS production was 13.01 g/L at 5 days culture time. EPS production was examined in a 5 L bioreactor, and an unstructured kinetic model for EPS formation was well developed. The verified investigations in the large-scale cultivation system showed that the developed models are able to predict the submerged cultivation process of EPS formation. Current results revealed that the submerged cultivation conditions can be utilized to control EPS production, and the unstructured models developed are suitable for explaining EPS production by A. luteo-virens Sacc QH in a large-scale cultivation bioreactor.

Antioxidant property and production of exopolysaccharide from Armillaria mellea in submerged cultures: Effect of culture aeration rate

“…Higher aeration rates seem to reduce the EPS production. Xu et al reported that the optimal condition for EPS production of Armillaria luteo‐virens Sacc QH by submerged cultures was at a low aeration rate of 0.5 vvm 21, which is equivalent to that from our results. It is possible that higher aeration rates provide suitable environments for metabolic pattern of cell growth but not for EPS biosynthesis, resulting in an inhibition in EPS formation at a slightly high DO concentration.…”

“…Submerged culture is an efficient polysaccharide production approach by mushrooms 11–13, 20. Considerable attention has been focused in the last decade on polysaccharide production optimization of submerged cultures from a variety of edible and medicinal mushrooms 16, 20, 21. Several reports pointed out that yield, chemical structure, molecular weight and biological properties of fermented polysaccharides in submerged cultures depend highly on environmental conditions and nutritional compositions 13, 20–23.…”

“…Considerable attention has been focused in the last decade on polysaccharide production optimization of submerged cultures from a variety of edible and medicinal mushrooms 16, 20, 21. Several reports pointed out that yield, chemical structure, molecular weight and biological properties of fermented polysaccharides in submerged cultures depend highly on environmental conditions and nutritional compositions 13, 20–23. Culture aeration rate is one of the most important environmental parameters to influence polysaccharide production.…”

“…Recently, the effect of culture aeration rate on medicinal exopolysaccharide (EPS) production improvement from mushrooms or enthomopathogenic fungi has been reported 24–28. Although several researchers have studied the submerged culture conditions on EPS production by A. mellea 20 and Armillaria luteo‐virens Sacc QH 21, little effort has been devoted to the effect of culture aeration rate on EPS production from A. mellea in submerged cultures.…”

Determination of fatty acids from mushrooms using high performance liquid chromatography with fluorescence detection and online mass spectrometry

“…Over the years, A. luteo-virens has been traditionally consumed by local residents because of its excellent flavor and texture (Li, 2005). Recently, more attentions have been paid to this wild mushroom including isolation of lectin (Feng et al, 2006) and polysaccharides (Liu, Yu, Mao, Meng, & Liu, 2007), cultivation of mycelium (Jiao, Chen, Zhou, Zhang, & Chen, 2008;Xu, Fu, Chen, & Liu, 2010) and investigation of antioxidative and antitumor activities (Li, Chen, & Bi, 2004). Furthermore, eighteen amino acids, three vitamins (Diao, 1997) and ten minerals (Li & Diao, 2008) have been found in A. luteo-virens.…”