TY - JOUR
T1 - Bacillus sphaericus LMG 22257 is physiologically suitable for self-healing concrete
AU - Wang, Jianyun
AU - Jonkers, Henk M.
AU - Boon, Nico
AU - De Belie, Nele
PY - 2017/6/1
Y1 - 2017/6/1
N2 - The suitability of using a spore-forming ureolytic strain, Bacillus sphaericus, was evaluated for self-healing of concrete cracks. The main focus was on alkaline tolerance, calcium tolerance, oxygen dependence, and low-temperature adaptability. Experimental results show that B. sphaericus had a good tolerance. It can grow and germinate in a broad range of alkaline pH. The optimal pH range is 7 ∼ 9. High alkaline conditions (pH 10 ∼ 11) slow down but not stop the growth and germination. Oxygen was strictly needed during bacterial growth and germination, but not an essential factor during bacterial urea decomposition. B. sphaericus also had a good Ca tolerance, especially at a high bacterial concentration of 108 cells/mL; no significant influence was observed on bacterial ureolytic activity of the presence of 0.9M Ca2+. Furthermore, at a low temperature (10 °C), bacterial spores germinated and revived ureolytic activity with some retardation. However, this retardation can be counteracted by using a higher bacterial concentration and by supplementing yeast extract. It can be concluded that B. sphaericus is a suitable bacterium for application in bacteria-based self-healing concrete.
AB - The suitability of using a spore-forming ureolytic strain, Bacillus sphaericus, was evaluated for self-healing of concrete cracks. The main focus was on alkaline tolerance, calcium tolerance, oxygen dependence, and low-temperature adaptability. Experimental results show that B. sphaericus had a good tolerance. It can grow and germinate in a broad range of alkaline pH. The optimal pH range is 7 ∼ 9. High alkaline conditions (pH 10 ∼ 11) slow down but not stop the growth and germination. Oxygen was strictly needed during bacterial growth and germination, but not an essential factor during bacterial urea decomposition. B. sphaericus also had a good Ca tolerance, especially at a high bacterial concentration of 108 cells/mL; no significant influence was observed on bacterial ureolytic activity of the presence of 0.9M Ca2+. Furthermore, at a low temperature (10 °C), bacterial spores germinated and revived ureolytic activity with some retardation. However, this retardation can be counteracted by using a higher bacterial concentration and by supplementing yeast extract. It can be concluded that B. sphaericus is a suitable bacterium for application in bacteria-based self-healing concrete.
KW - Alkaline tolerance
KW - Bio-CaCO
KW - Ca tolerance
KW - Oxygen dependence
KW - Temperature adaptability
KW - Ureolytic activity
UR - http://www.scopus.com/inward/record.url?scp=85016506564&partnerID=8YFLogxK
U2 - 10.1007/s00253-017-8260-2
DO - 10.1007/s00253-017-8260-2
M3 - Article
C2 - 28365797
AN - SCOPUS:85016506564
SN - 0175-7598
VL - 101
SP - 5101
EP - 5114
JO - Applied Microbiology and Biotechnology
JF - Applied Microbiology and Biotechnology
IS - 12
ER -