title: Shelf-life enhancement of bio-inoculant formulation by optimizing the trace metals ions in the culture medium for production of DAPG using fluorescent pseudomonad R62.
abstract: Statistical experimental design was used to optimize the concentration of trace elements for production of antifungal compound, 2,4-diacetylphloroglucinol (DAPG), from fluorescent pseudomonad R62 in shake-flask cultivation. The selection of the trace metal ions, influencing DAPG production, was done using Plackett-Burman design (PBD). Only Zn(2+), Mn(2+) and MoO(4)(2-) were the most significant components (p<0.05). A quadratic model was used to fit the response. Application of response surface methodology (RSM) revealed that the optimum values of the salts of the trace elements Zn(2+) (ZnSO(4)·7H(2)O), Mn(2+) (MnCl(2)·4H(2)O), and MoO(4)(2-) (Na(2)MoO(4)·2H(2)O) were 83, 42 and 135μM, respectively, to achieve 125 mg/L of DAPG, which was nearly 13-fold more compared to its production in basal synthetic medium in shake flask. The studies in 14L bioreactor resulted in 135 mg/L of DAPG at the end of 36 h of cultivation. The culture broth containing 125 mg/L of DAPG was found to be sufficient for keeping the bio-inoculant viable in non-sterile talcum powder-based formulations (which contained 25μg DAPG/g carrier) when stored at 28°C for 6 months. The structure of the purified DAPG was confirmed using (1)H NMR and mass spectrometry.
authors: Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
authors: K
authors: K
authors: Saharan
authors: M V R K
authors: MV
authors: Sarma
authors: A
authors: A
authors: Prakash
authors: B N
authors: BN
authors: Johri
authors: V S
authors: VS
authors: Bisaria
authors: V
authors: V
authors: Sahai
mesh_terms: D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D003470:Culture Media / Q000737:chemistry*; D003627:Data Interpretation, Statistical; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015233:Models, Statistical; D010696:Phloroglucinol / Q000031:analogs & derivatives / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D011551:Pseudomonas fluorescens / Q000254:growth & development / Q000378:metabolism*; D014131:Trace Elements / Q000378:metabolism*
chemical_list: D003470:Culture Media; D014131:Trace Elements; C059817:2,4-diacetylphloroglucinol; D010696:Phloroglucinol