title: Use of response surface methodology to evaluate the effect of metal ions (Ca2+, Ni2+, Mn2+, Cu2+) on production of antifungal compounds by Paenibacillus polymyxa.
abstract: The effects of four metal ions (Ca(2+), Ni(2+), Mn(2+) and Cu(2+)) were evaluated on growth and production of antifungal compounds by Paenibacillus polymyxa SQR-21 and a quadratic predictive model was developed using response surface methodology (RSM). The results revealed, Mn(2+) and Ni(2+) showed most positive synergistic interactive affect on production of antifungal compounds followed by the positive interactive synergistic affect of Cu(2+) and Ni(2+) and then Mn(2+) and Cu(2+). While the interactive effect of Ca(2+) with all other three metals inhibited the production of antifungal compounds. The Mn(2+) (P=0.0384), Ni(2+) (P=0.0004) and Cu(2+) (P=0.0117) significantly affected the production of antifungal compounds while the effect of Ca(2+) (P=0.1851) was less significant. The maximum growth (OD(600)=1.55) was obtained at 500 (0), 125 (0), 100 (-2) and 37.5 (0) microM levels and the maximum size of inhibition zone (31 mm) was measured at 400 (-1), 150 (1), 400 (1) and 25 microM (-1) levels of Ca(2+), Mn(2+), Ni(2+) and Cu(2+), respectively. The RSM model provided an easy and effective way to determine the interactive effect of metal ions on production of antifungal compounds by P. polymyxa SQR-21 so that optimum media recipes can be developed to produce maximum amounts of antifungal compounds under laboratory and commercial fermentation conditions.
authors.affiliation: Jiangsu Provincial Key Lab for Organic Slid Waste Utilization, Nanjing Agricultural University, No 1, Weigang Road, Nanjing, 210095 Jiangsu Province, China.
authors.forename: Waseem
authors.initials: W
authors.lastname: Raza
authors.forename: Wu
authors.initials: W
authors.lastname: Hongsheng
authors.forename: Shen
authors.initials: S
authors.lastname: Qirong
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D003300:Copper / Q000737:chemistry*; D017931:DNA Primers / Q000737:chemistry; D005285:Fermentation; D007477:Ions / Q000737:chemistry; D008345:Manganese / Q000737:chemistry*; D008970:Molecular Weight; D009532:Nickel / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D056507:Paenibacillus / Q000378:metabolism; D012044:Regression Analysis; D013499:Surface Properties
chemical_list: D000935:Antifungal Agents; D017931:DNA Primers; D007477:Ions; D008345:Manganese; D002244:Carbon; D003300:Copper; D009532:Nickel; D009584:Nitrogen