Impact of different pH control agents on biopesticidal activity of Bacillus thuringiensis during the fermentation of starch industry wastewater.
Different pH control agents (NaOH/H(2)SO(4)--SodSulp, NaOH/CH(3)COOH--SodAcet, NH(4)OH/CH(3)COOH--AmmoAcet and NH(4)OH/H(2)SO(4)--AmmoSulp) were used to investigate their effects on growth, enzyme production (alkaline protease and amylase), and entomotoxicity of Bacillus thuringiensis var. kurstaki HD-1 (Btk) against eastern spruce budworm larvae (Choristoneura fumiferana) using starch industry wastewater (SIW) as a raw material in a 15-l fermentor. AmmoSulp and SodSulp were found to be the best pH control agents for alkaline protease and amylase production, respectively; whereas, the fermented broth obtained by using SodAcet as pH control agents recorded the highest delta-endotoxin production of 1043.0 mg/l and entomotoxicity value 18.4 x 10(9) SBU/l. Entomotoxicity of re-suspended centrifuged pellet in one-tenth of original volume in case of SodAcet as pH control agents was 26.7 x 10(9) SBU/l and was the highest value compared to three other pH control agents.
Vu
Khanh Dang
KD
INRS-ETE, Université du Québec, 490, Rue de la Couronne, Quebec, QC, G1K 9A9, Canada.
Tyagi
R D
RD
Valéro
J R
JR
Surampalli
R Y
RY
D000681:Amylases / Q000378:metabolism; D000818:Animals; D001413:Bacillus thuringiensis / Q000254:growth & development / Q000378:metabolism*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000633:toxicity; D001681:Biological Assay; D015169:Colony Count, Microbial; D004731:Endotoxins / Q000096:biosynthesis / Q000633:toxicity; D005285:Fermentation; D006460:Hemolysin Proteins / Q000096:biosynthesis / Q000633:toxicity; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis*; D007300:Insect Control; D007915:Lepidoptera; D010572:Pest Control, Biological; D012697:Serine Endopeptidases / Q000378:metabolism; D013171:Spores, Bacterial; D013213:Starch / Q000737:chemistry*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007220:Industrial Waste; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D013213:Starch; D000681:Amylases; D012697:Serine Endopeptidases; C032923:microbial serine proteinases