title: Microbial production of plant hormones: Opportunities and challenges.
abstract: Plant hormones are a class of organic substances which are synthesized during the plant metabolism. They have obvious physiological effect on plant growth at very low concentrations. Generally, plant hormones are mainly divided into 5 categories: auxins, cytokinins, ethylene, gibberellins (GAs) and abscisic acid (ABA). With the deepening of research, some novel plant hormones such as brassinosteroid and salicylates have been found and identified. The plant hormone products are mainly obtained through plant extraction, chemical synthesis as well as microbial fermentation. However, the extremely low yield in plants and relatively complex chemical structure limit the development of the former 2 approaches. Therefore, more attention has been paid into the microbial fermentative production. In this commentary, the developments and technological achievements of the 2 important plant hormones (GAs and ABA) have been discussed. The discovery, producing strains, fermentation technologies, and their accumulation mechanisms are first introduced. Furthermore, progresses in the industrial mass scale production are discussed. Finally, guidelines for future studies for GAs and ABA production are proposed in light of the current progress, challenges and trends in the field. With the widespread use of plant hormones in agriculture, we believe that the microbial production of plant hormones will have a bright future.
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.
authors.forename: Tian-Qiong
authors.initials: TQ
authors.lastname: Shi
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.
authors.forename: Hui
authors.initials: H
authors.lastname: Peng
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.
authors.forename: Si-Yu
authors.initials: SY
authors.lastname: Zeng
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.
authors.forename: Rong-Yu
authors.initials: RY
authors.lastname: Ji
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.
authors.forename: Kun
authors.initials: K
authors.lastname: Shi
authors.affiliation: b School of Pharmaceutical Sciences, Nanjing Tech University , Nanjing , People's Republic of China.|c State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.|d Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) , Nanjing , People's Republic of China.
authors.forename: He
authors.initials: H
authors.lastname: Huang
authors.affiliation: a College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University , Nanjing , People's Republic of China.|d Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) , Nanjing , People's Republic of China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Ji
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D001709:Biotechnology / Q000639:trends; D005030:Ethylenes / Q000378:metabolism; D005658:Fungi / Q000378:metabolism*; D005875:Gibberellins / Q000378:metabolism; D007210:Indoleacetic Acids / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*
chemical_list: D005030:Ethylenes; D005875:Gibberellins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D000040:Abscisic Acid; C036216:ethylene
keywords: abscisic acid; fermentation; filamentous fungi; gibberellins; plant hormones; secondary metabolites