title: Nutrient recycle from defatted microalgae (Aurantiochytrium) with hydrothermal treatment for microalgae cultivation.
abstract: Defatted heterotrophic microalgae (Aurantiochytrium limacinum SR21) was treated with high temperature water (175-350°C, 10-90min) to obtain nitrogen and phosphorous nutrients as a water soluble fraction (WS). Yields of nitrogen and phosphorous recovered in WS varied from 38 to 100% and from 57 to 99%, respectively. Maximum yields of nitrogen containing compounds in WS were proteins (43%), amino acids (12%) and ammonia (60%) at treatment temperatures of 175, 250 and 350°C, respectively. Maximum yield of phosphorous in WS was 99% at a treatment temperature of 250°C. Cultivation experiments of microalgae (A. limacinum SR21) using WS obtained at 200 and 250°C showed positive growth. Water soluble fractions from hydrothermal treatment of defatted microalgae are effective nitrogen and phosphorous nutrient sources for microalgae cultivation.
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan. Electronic address: aida@scf.che.tohoku.ac.jp.
authors.forename: Taku Michael
authors.initials: TM
authors.lastname: Aida
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Ryouma
authors.initials: R
authors.lastname: Maruta
authors.affiliation: Research Center of Supercritical Fluid Technology, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan; Faculty of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Yuuhiko
authors.initials: Y
authors.lastname: Tanabe
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Minori
authors.initials: M
authors.lastname: Oshima
authors.affiliation: Research Center of Supercritical Fluid Technology, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Nonaka
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kujiraoka
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Kumagai
authors.affiliation: Research Center of Supercritical Fluid Technology, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Ota
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Iwane
authors.initials: I
authors.lastname: Suzuki
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, Tennodai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan.
authors.forename: Makoto M
authors.initials: MM
authors.lastname: Watanabe
authors.affiliation: Research Center of Supercritical Fluid Technology, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Inomata
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan; Research Center of Supercritical Fluid Technology, Tohoku University, Aramaki Aza Aoba 6-6-11, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Smith
mesh_terms: D018533:Biomass; D005502:Food; D052836:Heterotrophic Processes; D006358:Hot Temperature; D058086:Microalgae / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism*; D059027:Recycling; D058009:Stramenopiles / Q000378:metabolism; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D010758:Phosphorus; D009584:Nitrogen
keywords: Amino acid; Biosolid treatment process; Internal recycle; Phosphorous; Protein