title: In vitro azadirachtin production by hairy root cultivation of Azadirachta indica in nutrient mist bioreactor.
abstract: Azadirachtin, a well-known biopesticide is a secondary metabolite conventionally extracted from the seeds of Azadirachta indica. The present study involved in vitro azadirachtin production by developing hairy roots of A. indica via Agrobacterium rhizogenes-mediated transformation of A. indica explants. Liquid culture of hairy roots was established in shake flask to study the kinetics of growth and azadirachtin production. A biomass production of 13.3 g/L dry weight (specific growth rate of 0.7 day(-1)) was obtained after 25 days of cultivation period with an azadirachtin yield of 3.3 mg/g root biomass. To overcome the mass transfer limitation in conventionally used liquid-phase reactors, batch cultivation of hairy roots was carried out in gas-phase reactors (nutrient spray and nutrient mist bioreactor) to investigate the possible scale-up of A. indica hairy root culture. The nano-size nutrient mist particles generated from the nozzle of the nutrient mist bioreactor could penetrate till the inner core of the inoculated root matrix, facilitating uniform growth during high-density cultivation of hairy roots. A biomass production of 9.8 g/L dry weight with azadirachtin accumulation of 2.8 mg/g biomass (27.4 mg/L) could be achieved in 25 days of batch cultivation period, which was equivalent to a volumetric productivity of 1.09 mg/L per day of azadirachtin.
authors.affiliation: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi 110 016, India. smita@iitm.ac.in
authors.forename: Smita
authors.initials: S
authors.lastname: Srivastava
authors.forename: A K
authors.initials: AK
authors.lastname: Srivastava
mesh_terms: D031601:Azadirachta / Q000254:growth & development* / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D046508:Culture Techniques / Q000295:instrumentation / Q000379:methods*; D005740:Gases / Q000737:chemistry; D007700:Kinetics; D036701:Limonins / Q000096:biosynthesis*; D018517:Plant Roots / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D005740:Gases; D036701:Limonins; C010329:azadirachtin