Abstract:
Microbial Induced Carbonate Precipitation (MICP) is a widely explored technique
that involves utilizing bacterially produced carbonate biominerals for improving the
engineering properties of soils. When this novel approach is used in cementing
sandy soils in nearshore areas, it is necessary to identify suitable bacterial strains
which are resistant to high saline dynamic marine environments. Thus, current
study was carried out to isolate and identify ureolytic bacteria from Sri Lankan
beach sand and to check their suitability for use in MICP. To accomplish this,
bacterial strains were isolated from beach sand samples and urease activity was
determined. MICP capability was evaluated by cultivating the species on agar plates
containing CaCh and urea. Based on these results, four isolates having high
feasibility to induce bacterially precipitated calcium carbonates were selected and
identified by 16S rDNA gene sequencing. Two strains were identified as belonging
to Halomonas sp. and other two to Sulfitobacter sp. and OceanobaciUus sp. genera.
Further analysis was done to determine the bacterial cell growth of isolates at
different temperatures and concluded that all four isolates have a more stable
growth at temperature close to 30°C. Isolates were evaluated for their biosafety and
found to be non pathogenic. However, detailed analysis on biomineralization by the
selected isolates and their biological behaviour is recommended prior to any large
scale applications.
Citation:
Nayanthara, P.G.N., Dassanayake, A.B.N., Nakashima, K., & Kawasaki, S. (2018). A preliminary investigation on isolation and identification of marine bacteria for biocementation in nearshore environments. In A.M.K.B. Abeysinghe & G.V.I. Samaradivakara (Eds.), Proceedings of International Symposium on Earth Resources Management & Environment 2018 (pp. 111-118). Department of Earth Resources Engineering, University of Moratuwa.