title: Arachidonic acid production by Mortierella alpina using raw crop materials.
abstract: BACKGROUND
  Arachidonic acid (ARA) is one of the three essential fatty acids, and it is important for human body to keep healthy and is widely used. At present, expensive materials such as glucose and yeast extract are generally reported to be optimal for ARA production. A new cost-effective fermentation process including cheaper material for ARA production is of great significance.
  
  
  METHODS
  Feasibility of using corn meal and powdered soybean for fungal growth and lipid accumulation was evaluated by means of single factor test. N-hexadecane concentration was optimized, and the effect of temperature on biomass and ARA content was examined.
  
  
  RESULTS
  Mortierella alpina made better use of the aforementioned material as carbon and nitrogen sources for both hyphae growth and ARA production compared with glucose and yeast extract. Maximal levels of 10.9 g/L ARA and 26.1 g/L total lipids were obtained when 66 g/L corn meal, 54 g/L soybean meal and 6% (v/v) n-hexadecane were supplemented. A temperature-shift strategy involved three steps, namely, 30°C (3 days) - 25°C (4 days) - 20°C (4 days), which further improved ARA production by 24.7%.
  
  
  CONCLUSIONS
  Several factors such as carbon and nitrogen sources, temperature and dissolved oxygen had great influence on biomass and microbial oil production. Mortierella alpina preferred corn and soybean meal compared with glucose and yeast extract, which would surely alleviate the high cost of ARA production. Based on this study, the new process is both low cost and practicable.
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, China.
authors.forename: Ganggang
authors.initials: G
authors.lastname: Cao
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, China.
authors.forename: Zhengbing
authors.initials: Z
authors.lastname: Guan
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, China.
authors.forename: Feixian G
authors.initials: FG
authors.lastname: Liu
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, China.
authors.forename: Xiangru
authors.initials: X
authors.lastname: Liao
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, China.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Cai
mesh_terms: D000473:Alkanes / Q000032:analysis / Q000378:metabolism; D016718:Arachidonic Acid / Q000032:analysis / Q000096:biosynthesis* / Q000191:economics; D002681:China; D003080:Cold Temperature; D017046:Cost Savings; D018556:Crops, Agricultural / Q000737:chemistry / Q000191:economics / Q000382:microbiology; D004041:Dietary Fats / Q000032:analysis / Q000191:economics / Q000378:metabolism; D004187:Disaccharides / Q000191:economics / Q000378:metabolism; D005240:Feasibility Studies; D005285:Fermentation; D005511:Food Handling / Q000191:economics; D057141:Food, Preserved / Q000032:analysis* / Q000191:economics / Q000382:microbiology; D006601:Hexoses / Q000191:economics / Q000378:metabolism; D006358:Hot Temperature; D050356:Lipid Metabolism; D020094:Mortierella / Q000254:growth & development / Q000378:metabolism*; D012639:Seeds / Q000737:chemistry* / Q000382:microbiology; D013025:Glycine max / Q000737:chemistry* / Q000382:microbiology; D013997:Time Factors; D003313:Zea mays / Q000737:chemistry* / Q000382:microbiology
chemical_list: D000473:Alkanes; D004041:Dietary Fats; D004187:Disaccharides; D006601:Hexoses; D016718:Arachidonic Acid; C007932:n-hexadecane
keywords: Mortierella alpina; arachidonic acid; n-hexadecane; raw crop materials; temperature shift