W Krusong1, S Kerdpiboon2, S Pornpukdeewattana1, A Jindaprasert1. 1. Fermentation Technology Division, Faculty of Agro-Industry, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand. 2. Food Science Division, Faculty of Agro-Industry, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand.
Abstract
AIMS: To offset the negative effects of aeration on bacterial cellulose (BC) production by acetic acid bacteria using enmeshed cellulose microfibrils (CM) on luffa sponge matrices (LSM). METHODS AND RESULTS: The CM were enmeshed on LSM (LSM-CM). The optimal amount of LSM-CM was determined for BC production under aerated conditions. Without LSM-CM, no BC was produced in seven out of nine production cycles at the highest aeration rate (9 l min-1 ). However, with 0·5% LSM-CM and an aeration rate of 3 l min-1 , a satisfactory oxygen transfer coefficient was achieved, and also a good yield of BC (5·24 g l-1 ). Moreover, the LSM-CM was able to be recycled through nine consecutive BC production cycles. The highest BC yields (from 5·8 ± 0·4 to 6·6 ± 0·4 g l-1 ) were associated with high bacterial biomass and this was confirmed by scanning electron microscopy. CONCLUSIONS: We confirm that LSM-CM works well as a starter. Microenvironments low in dissolved oxygen within the matrices of LSM-CM are important for BC production under aeration conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The LSM-CM provides a microenvironment which offsets the negative effects of aeration on BC production. A sustainable, economic process for mass BC production is described using recycled LSM-CM with aeration.
AIMS: To offset the negative effects of aeration on bacterial cellulose (BC) production by acetic acid bacteria using enmeshed cellulose microfibrils (CM) on luffa sponge matrices (LSM). METHODS AND RESULTS: The CM were enmeshed on LSM (LSM-CM). The optimal amount of LSM-CM was determined for BC production under aerated conditions. Without LSM-CM, no BC was produced in seven out of nine production cycles at the highest aeration rate (9 l min-1 ). However, with 0·5% LSM-CM and an aeration rate of 3 l min-1 , a satisfactory oxygen transfer coefficient was achieved, and also a good yield of BC (5·24 g l-1 ). Moreover, the LSM-CM was able to be recycled through nine consecutive BC production cycles. The highest BC yields (from 5·8 ± 0·4 to 6·6 ± 0·4 g l-1 ) were associated with high bacterial biomass and this was confirmed by scanning electron microscopy. CONCLUSIONS: We confirm that LSM-CM works well as a starter. Microenvironments low in dissolved oxygen within the matrices of LSM-CM are important for BC production under aeration conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The LSM-CM provides a microenvironment which offsets the negative effects of aeration on BC production. A sustainable, economic process for mass BC production is described using recycled LSM-CM with aeration.