title: Dynamic microstructures and fractal characterization of cell wall disruption for microwave irradiation-assisted lipid extraction from wet microalgae.
abstract: To extract lipids from wet microalgae through cell disruption, the effects of microwave treatment on the dynamic cell wall microstructures were investigated. The fractal dimension of raw, untreated microalgal cells was 1.46. The disruption level of microalgal cell walls was enhanced when microwave treatment temperature increased from 80 to 120°C, resulting in an increase in microalgal cell fractal dimension from 1.61 to 1.91. The cell wall thickness and pore diameters in cell walls increased from 0.11 to 0.59 μm and from 0.005 to 0.18 μm, respectively, when microwave treatment time increased from 0 to 20 min. The outer pectin layers of cell walls gradually detached and the porosity of inner cellulose layers increased when microwave treatment time increased to 26 min. The initial point of disruption appeared at the maximum curvature (approximately 1.01×10(7) m(-1)) of cell walls. Numbers of short-chain and saturated lipids increased because of microwave electromagnetic effect.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. Electronic address: juncheng@zju.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Cheng
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Yun
authors.initials: Y
authors.lastname: Huang
authors.forename: Jia
authors.initials: J
authors.lastname: Feng
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhou
authors.forename: Kefa
authors.initials: K
authors.lastname: Cen
mesh_terms: D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism*; D002708:Chlorella / Q000737:chemistry / Q000166:cytology / Q000187:drug effects; D017709:Fractals; D008055:Lipids / Q000302:isolation & purification*; D058086:Microalgae / Q000737:chemistry* / Q000166:cytology / Q000187:drug effects; D008872:Microwaves; D016062:Porosity; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000494:pharmacology*
chemical_list: D008055:Lipids; D014867:Water
keywords: Cell wall; Lipids; Microalgae; Microstructure; Microwave