title: Photostabilization of Bacillus thuringiensis fermented wastewater and wastewater sludge based biopesticides using additives.
abstract: Photoprotection (against UV-A and UV-B radiations) of the active components of Bacillus thuringiensis var. kurstaki obtained from the fermentation of various culture media was investigated. The culture media comprised: starch industry wastewater; secondary wastewater sludge (non-hydrolyzed and hydrolyzed) and soya (used as a reference). Photoprotection was carried out by using various UV-protection additives, namely, para-aminobenzoic acid, lignosulfonic acid and molasses at different concentrations (0.1%, 0.15% and 0.2%, w/w). In the absence of UV-protection agents, secondary sludge demonstrated natural UV protection with half-lives ranging from 3.25 to 3.4 d. The half-life for soya and starch industry wastewater was 1.9 and 1.8 d, respectively. Para-amino-benzoic acid as a UV-protection agent at 0.20% (w/w) gave excellent UV-protection for soya and starch industry wastewater with half-lives being 5.9 and 7 d, respectively. Likewise, lignosulfonic acid at 0.20% (w/w) was an effective photostabilizer for hydrolyzed and non-hydrolyzed secondary sludge with half-lives of 7.25 and 8 d, respectively. Hence, when similar concentration of the UV-protection additives was used, photoprotection was higher for the alternative media than the conventional soya medium, validating the technical feasibility of using three additives.
authors.affiliation: INRS Eau, Terre et Environnement (INRS-ETE), Québec, Canada.
authors.forename: K D
authors.initials: KD
authors.lastname: Adjalle
authors.forename: S K
authors.initials: SK
authors.lastname: Brar
authors.forename: R D
authors.initials: RD
authors.lastname: Tyagi
authors.forename: J R
authors.initials: JR
authors.lastname: Valéro
authors.forename: R Y
authors.initials: RY
authors.lastname: Surampalli
mesh_terms: D010129:4-Aminobenzoic Acid / Q000494:pharmacology; D001413:Bacillus thuringiensis / Q000378:metabolism* / Q000528:radiation effects*; D005285:Fermentation; D008031:Lignin / Q000031:analogs & derivatives / Q000494:pharmacology; D008965:Molasses; D011835:Radiation Protection / Q000379:methods*; D012722:Sewage / Q000382:microbiology*; D014466:Ultraviolet Rays; D014871:Water Microbiology
chemical_list: D012722:Sewage; C001545:lignosulfuric acid; D008031:Lignin; D010129:4-Aminobenzoic Acid