title: Differential regulation of fatty acid biosynthesis in two Chlorella species in response to nitrate treatments and the potential of binary blending microalgae oils for biodiesel application.
abstract: This study was undertaken to investigate the effects of different nitrate concentrations in culture medium on oil content and fatty acid composition of Chlorella vulgaris (UMT-M1) and Chlorella sorokiniana (KS-MB2). Results showed that both species produced significant higher (p<0.05) oil content at nitrate ranging from 0.18 to 0.66 mM with C. vulgaris produced 10.20-11.34% dw, while C. sorokiniana produced 15.44-17.32% dw. The major fatty acids detected include C16:0, C18:0, C18:1, C18:2 and C18:3. It is interesting to note that both species displayed differentially regulated fatty acid accumulation patterns in response to nitrate treatments at early stationary growth phase. Their potential use for biodiesel application could be enhanced by exploring the concept of binary blending of the two microalgae oils using developed mathematical equations to calculate the oil mass blending ratio and simultaneously estimated the weight percentage (wt.%) of desirable fatty acid compositions.
authors.affiliation: Institute of Marine Biotechnology, Department of Biological Sciences, Faculty of Science and Technology, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia. cha_ts@umt.edu.my
authors.forename: Thye San
authors.initials: TS
authors.lastname: Cha
authors.forename: Jian Woon
authors.initials: JW
authors.lastname: Chen
authors.forename: Eng Giap
authors.initials: EG
authors.lastname: Goh
authors.forename: Ahmad
authors.initials: A
authors.lastname: Aziz
authors.forename: Saw Hong
authors.initials: SH
authors.lastname: Loh
mesh_terms: D001483:Base Sequence; D056804:Biofuels / Q000032:analysis*; D018533:Biomass; D002452:Cell Count; D002708:Chlorella / Q000166:cytology / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D004275:DNA, Ribosomal / Q000235:genetics; D005227:Fatty Acids / Q000096:biosynthesis*; D058086:Microalgae / Q000187:drug effects / Q000378:metabolism*; D009566:Nitrates / Q000494:pharmacology*; D009821:Oils / Q000378:metabolism*; D010802:Phylogeny; D015203:Reproducibility of Results; D013045:Species Specificity
chemical_list: D056804:Biofuels; D004275:DNA, Ribosomal; D005227:Fatty Acids; D009566:Nitrates; D009821:Oils