title: Regenerative Astaxanthin Extraction from a Single Microalgal (Haematococcus pluvialis) Cell Using a Gold Nano-Scalpel.
abstract: Milking of microalgae, the process of reusing the biomass for continuous production of target compounds, can strikingly overcome the time and cost constraints associated with biorefinery. This process can significantly improve production efficiency of highly valuable chemicals, for example, astaxanthin (AXT) from Haematococcus pluvialis. Detailed understanding of the biological process of cell survival and AXT reaccumulation after extraction would be of great help for successful milking. Here we report extraction of AXT from a single cell of H. pluvialis through incision of the cell wall by a gold nanoscalpel (Au-NS), which allows single-cell analysis of wound healing and reaccumulation of AXT. Interestingly, upon the Au-NS incision, the cell could reaccumulate AXT at a rate two times faster than the control cells. Efficient extraction as well as minimal cellular damage, keeping cells alive, could be achieved with the optimized shape and dimensions of Au-NS: a well-defined sharp tip, thickness under 300 nm, and 1-3 μm of width. The demonstration of regenerative extraction of AXT at a single cell level hints toward the potential of a milking process for continuous recovery of target compounds from microalgae while keeping the cells alive.
authors.affiliation: Biomass and Waste Energy Laboratory, Korea Institute of Energy Research , Daejeon 34129, Korea.|Department of Chemistry and Bioengineering, Tampere University of Technology , Tampere 33720, Finland.
authors.forename: Ramasamy
authors.initials: R
authors.lastname: Praveenkumar
authors.forename: Raekeun
authors.initials: R
authors.lastname: Gwak
authors.forename: Mijeong
authors.initials: M
authors.lastname: Kang
authors.affiliation: Department Chemical Engineering, Ajou University , Suwon 16499, Korea.
authors.forename: Tae Soup
authors.initials: TS
authors.lastname: Shim
authors.forename: Soojeong
authors.initials: S
authors.lastname: Cho
authors.affiliation: Biomass and Waste Energy Laboratory, Korea Institute of Energy Research , Daejeon 34129, Korea.
authors.forename: Jiye
authors.initials: J
authors.lastname: Lee
authors.affiliation: Biomass and Waste Energy Laboratory, Korea Institute of Energy Research , Daejeon 34129, Korea.
authors.forename: You-Kwan
authors.initials: YK
authors.lastname: Oh
authors.affiliation: Biomass and Waste Energy Laboratory, Korea Institute of Energy Research , Daejeon 34129, Korea.
authors.forename: Kyubock
authors.initials: K
authors.lastname: Lee
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim
mesh_terms: D000460:Chlorophyta / Q000378:metabolism*; D006046:Gold / Q000737:chemistry*; D018613:Microscopy, Confocal; D049329:Nanostructures / Q000737:chemistry*; D024341:Xanthophylls / Q000737:chemistry / Q000302:isolation & purification
chemical_list: D024341:Xanthophylls; D006046:Gold; C005948:astaxanthine
keywords: astaxanthin; mechanotransduction; microalgae; nanoscalpel; regenerative extraction; wound-healing