Prevent the degradation of algicidal ability in Scenedesmus-lysing bacteria using optimized cryopreservation

Chunli Liao*, Xiaobo Liu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

With the anthropogenic nutrient loading increasing, the frequency and impacts of harmful algal blooms (HABs) have intensified in recent years. To biocontrol HABs, many corresponding algal-lysing bacteria have been exploited successively. However, there are few studies on an effective algal-lysing culture collection to prevent cells from death and particularly the degradation of algicidal ability to their hosts. An optimized cryopreservation was developed and experiments on the validation of this method on preventing algicidal degradation and effects of this optimized cryopreservation on the survival rate of Scenedesmus-lysing bacterium, Enterobacter NP23, isolated from Scenedesmus sp. community, China, on the algicidal dynamic of Scenedesmus wuhanensis was investigated. The optimized cryoprotectant composition consists of 30.0 g/L gelatin, 48.5 g/L sucrose, and 28.4 g/L glycerol, respectively. Using this approach, the survival rate of NP23 cells can still maintain above 90 % and the algal-lysing rate only decline 4 % after the 18-month cryoprotection. Moreover, the 16 generations’ passage experiment showed a significant (p < 0.05) genetic stability of algicidal capacity after 18 months. The growth dynamic of S. wuhanensis was investigated in a 5-L bioreactor during 132 h in the absence or presence of NP23. As a result, NP23 has a significant (p < 0.05) inhibition to S. wuhanensis growth when injected into algal culture in the exponential phase at 60th hour. In addition, S. wuhanensis culture initially with NP23 exhibited a slow growth, performing a prolonged lag phase without a clear stationary phase and then rapidly decreased. Our findings, combined with the capacity of preventing the degradation of algicidal ability collectively suggest that the use of this opitimized cryopreservation may be a promising strategy for maintaining algicidal cells.

Original languageEnglish
Pages (from-to)5925-5930
Number of pages6
JournalEnvironmental Science and Pollution Research
Volume23
Issue number6
DOIs
StatePublished - 1 Mar 2016
Externally publishedYes

Keywords

  • Algal-lysing bacterium
  • Cryopreservation
  • Degradation
  • Harmful algal blooms
  • Scenedesmus wuhanensis

Fingerprint Dive into the research topics of 'Prevent the degradation of algicidal ability in Scenedesmus-lysing bacteria using optimized cryopreservation'. Together they form a unique fingerprint.

Cite this