PMID- 31462752
OWN - NLM
STAT- MEDLINE
DCOM- 20201019
LR  - 20210110
IS  - 2045-2322 (Electronic)
IS  - 2045-2322 (Linking)
VI  - 9
IP  - 1
DP  - 2019 Aug 28
TI  - Evaluation of Microencapsulation Techniques for MICP Bacterial Spores Applied in 
      Self-Healing Concrete.
PG  - 12484
LID - 10.1038/s41598-019-49002-6 [doi]
LID - 12484
AB  - Concrete cracks must be repaired promptly in order to prevent structural damage 
      and to prolong the structural life of the building (or other such construction). 
      Biological self-healing concrete is a recent alternative technology involving the 
      biochemical reaction of microbial induced calcium carbonate precipitation (MICP). 
      This study determined the most appropriate technique to encapsulate spores of 
      Bacillus sphaericus LMG 22257 with sodium alginate so as to protect the bacterial 
      spores during the concrete mixing and hardening period. Three techniques 
      (extrusion, spray drying and freeze drying) to encapsulate the bacterial spores 
      with sodium alginate were evaluated. The freeze-drying process provided the 
      highest bacterial spore survival rate (100%), while the extruded and spray-dried 
      processes had a lower spore survival rate of 93.8% and 79.9%, respectively. To 
      investigate the viability of microencapsulated spores after being mixed with 
      mortar, the decomposed urea analysis was conducted. The results revealed that the 
      freeze-dried spores also showed the highest level of urea decomposition 
      (metabolic activity assay used as a surrogate marker of spore germination and 
      vegetative cell viability). Thus, the self-healing performance of concrete mixed 
      with freeze-dried spores was evaluated. The results showed that the crack healing 
      ratio observed from the mortar specimens with freeze-dried microencapsulated 
      spores were significantly higher than those without bacteria. This study revealed 
      that freeze drying has a high potential as a microencapsulation technique for 
      application to self-healing concrete technology.
FAU - Pungrasmi, Wiboonluk
AU  - Pungrasmi W
AD  - Associate Professor, Department of Environmental Engineering, Faculty of 
      Engineering, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, 10330, 
      Thailand.
AD  - Research Network of NANOTEC-CU on Environmental, Department of Environmental 
      Engineering, Chulalongkorn University, Bangkok, 10330, Thailand.
FAU - Intarasoontron, Jirapa
AU  - Intarasoontron J
AD  - Master student, Department of Environmental Engineering, Faculty of Engineering, 
      Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok, 10330, Thailand.
FAU - Jongvivatsakul, Pitcha
AU  - Jongvivatsakul P
AD  - Assistant Professor, Innovative Construction Materials Research Unit, Department 
      of Civil Engineering, Faculty of Engineering, Chulalongkorn University, Phayathai 
      Road, Pathumwan, Bangkok, 10330, Thailand.
FAU - Likitlersuang, Suched
AU  - Likitlersuang S
AUID- ORCID: 0000-0001-8289-3647
AD  - Professor, Centre of Excellence in Geotechnical and Geoenvironmental Engineering, 
      Department of Civil Engineering, Faculty of Engineering, Chulalongkorn 
      University, Phayathai Road, Pathumwan, Bangkok, 10330, Thailand. 
      fceslk@eng.chula.ac.th.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20190828
PL  - England
TA  - Sci Rep
JT  - Scientific reports
JID - 101563288
RN  - 0 (Alginates)
RN  - H0G9379FGK (Calcium Carbonate)
RN  - Lysinibacillus sphaericus
SB  - IM
MH  - *Alginates/chemistry/metabolism
MH  - *Bacillaceae/chemistry/metabolism
MH  - *Calcium Carbonate/chemistry/metabolism
MH  - *Construction Materials
MH  - *Spores, Bacterial/chemistry/metabolism
PMC - PMC6713760
COIS- The authors declare no competing interests.
EDAT- 2019/08/30 06:00
MHDA- 2020/10/21 06:00
PMCR- 2019/08/28
CRDT- 2019/08/30 06:00
PHST- 2019/01/07 00:00 [received]
PHST- 2019/08/19 00:00 [accepted]
PHST- 2019/08/30 06:00 [entrez]
PHST- 2019/08/30 06:00 [pubmed]
PHST- 2020/10/21 06:00 [medline]
PHST- 2019/08/28 00:00 [pmc-release]
AID - 10.1038/s41598-019-49002-6 [pii]
AID - 49002 [pii]
AID - 10.1038/s41598-019-49002-6 [doi]
PST - epublish
SO  - Sci Rep. 2019 Aug 28;9(1):12484. doi: 10.1038/s41598-019-49002-6.