کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
684300 | 889019 | 2009 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Entomotoxicity, protease and chitinase activity of Bacillus thuringiensis fermented wastewater sludge with a high solids content
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
NAGEPSμmaxN-acetyl glucosamine - N-استیل گلوکوزامینVIPs - VIP هاKLA - ارتش آزادیبخشParticle size - اندازه ذراتdissolved oxygen - اکسیژن محلولBacillus thuringiensis - باسیلوس تورنجینسیسSuspended solids - جامدات معلقMaximum specific growth rate - حداکثر سرعت رشد خاصEntomotoxicity - سموم زیستیVolumetric mass transfer coefficient - ضریب انتقال جرمی حجمیProtease activity - فعالیت پروتئازWastewater sludge - لجن آب آشامیدنیOUR - ماExtracellular polymeric substances - مواد پلیمری خارج سلولیOxygen uptake rate - میزان جذب اکسیژنViscosity - ویسکوزیته یا گرانرویVegetative insecticidal proteins - پروتئین های حشره کش گیاهیSurface tension - کشش سطحی
موضوعات مرتبط
مهندسی و علوم پایه
مهندسی شیمی
تکنولوژی و شیمی فرآیندی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
This study investigated the production of biopesticides, protease and chitinase activity by Bacillus thuringiensis grown in raw wastewater sludge at high solids concentration (30 g/L). The rheology of wastewater sludge was modified with addition of Tween-80 (0.2% v/v). This addition resulted in 1.6 and 1.3-fold increase in cell and spore count, respectively. The maximum specific growth rate (μmax) augmented from 0.17 to 0.22 hâ1 and entomotoxicity (Tx) increased by 29.7%. Meanwhile, volumetric mass transfer coefficient (kLa) showed marked variations during fermentation, and oxygen uptake rate (OUR) increased 2-fold. The proteolytic activity increased while chitinase decreased for Tween amended wastewater sludge, but the entomotoxicity increased. The specific entomotoxicity followed power law when plotted against spore concentration and the relation between Tx and protease activity was linear. The viscosity varied and volume percent of particles increased in Tween-80 amended wastewater sludge and particle size (D50) decreased at the end of fermentation. Thus, there was an increase in entomotoxicity at higher suspended solids (30 g/L) as Tween addition improved rheology (viscosity, particle size, surface tension); enhanced maximum growth rate and OUR.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Bioresource Technology - Volume 100, Issue 19, October 2009, Pages 4317-4325
Journal: Bioresource Technology - Volume 100, Issue 19, October 2009, Pages 4317-4325
نویسندگان
Satinder K. Brar, M. Verma, R.D. Tyagi, J.R. Valéro, R.Y. Surampalli,