?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=Survivability+of+Salmonella+typhimurium+L1388+and+Salmonella+enteritidis+L1225+under+stressful+growth+conditions&rft.creator=Ngwai%2C+YB&rft.creator=Wambebe%2C+C&rft.creator=Adachi%2C+Y&rft.subject=Online+Journal+of+Health+and+Allied+Sciences&rft.description=In+an+earlier+study+with+Salmonella+typhimurium+L1388+(ST)+and+Salmonella+enteritidis+L1225+(SE)+isolated+from+diseased+chickens%2C+we+found+that+SE+formed+more+biofilm+than+ST+on+abiotic+surfaces+in+a+time-dependent+manner.+Since+the+ability+of+salmonellae+to+survive+extreme+environment+is+related+to+their+virulence%2C+the+present+study+examined+the+survival+of+Salmonella+typhimurium+L1388+and+Salmonella+nteritidis+L1225+under+the+usual+stresses+that+salmonellae+encounter+during+their+life+cycle.+This+is+with+a+view+to+understanding+the+strains%E2%80%99+stress+tolerance+that+could+be+used+to+explain+their+virulence.+Incubation+at+37oC+for+various+time+periods+was+done+for%3A+i)+stationary+phase+(SP)+cells+at+pH+2.6%3B+ii)+log-phase+(LP)+cells+at+pH+4.0%3B+log-phase+or+stationary+phase+cells+in+broth+containing+iii)+hydrogen+peroxide%2C+iv)+sodium+chloride+and+v)+ethanol%3B+vi)+stationary+phase+cells+in+Hank%E2%80%99s+balanced+salt+solution+(single+strength)+containing+10%25+human+serum%3B+and+vii)+prolong+stationary+phase+cells.+Stationary+phase+cells+were+also+incubated+at+52oC+for+15+min.+Surviving+cells+at+the+various+incubation+times+were+counted+on+trypticase+soy+agar+(TSA)+after+appropriate+dilution+in+saline+and+overnight+incubation+at+37oC.+Growth+iron-poor+medium+was+determined+by+growing+a+single+bacterial+colony+in+Medium+A+with+shaking+at+37oC+or+40oC+for+24+h.+Statistics+was+done+by+one-way+analysis-of-variance+(ANOVA)+at+P+%3D+0.05.+Differences+in+the+survival+of+ST+and+SE+were+insignificant+(p%3E0.05)+in+acid+pH+at+both+pH+4.0+(p+%3D+0.3783)+and+pH+2.6+(p+%3D+0.4711)%3B+at+high+salinity+for+log-phase+(p+%3D+0.1416)+and+stationary+phase+(p+%3D+0.1816)+cells%3B+in+ethanol+(p+%3D+0.5984)%2C+human+serum+(p+%3D+0.8139)%2C+prolonged+stationary+phase+(p+%3D+0.3506)%3B+and+under+heat+(p+%3D+0.5766).+SE+was+significantly+(p%3C0.05%3B+p+%3D+0.0031)+more+tolerant+to+oxidative-killing+by+hydrogen+peroxide.+Culturable+growth+of+the+ST+and+SE+in+an+iron-poor+medium+A+revealed+insignificant+differences+at+37oC+(p+%3D+0.8381)+but+marginally+significant+at+40oC+(p+%3D+0.0508).+Thus%2C+with+the+exception+of+survival+in+hydrogen+peroxide%2C+SE+had+similar+response+pattern+with+ST+to+the+usual+stresses+that+salmonellae+encounter+during+their+life+cycle%2C+despite+the+former%E2%80%99s+preferential+ability+to+form+biofilm+on+abiotic+surfaces.+The+relationship+between+the+observed+enhanced+ability+of+SE+to+survive+in+hydrogen+peroxide+and+virulence+need+to+be+investigated+in+subsequent+study.&rft.publisher=Dr.+B.S.+Kakkilaya&rft.contributor=Kakkilaya%2C+Dr.+Srinivas&rft.date=2007-11-10&rft.type=Journal+(On-line%2FUnpaginated)&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.identifier=http%3A%2F%2Fcogprints.org%2F5847%2F1%2F2007-2-4.pdf&rft.identifier=++Ngwai%2C+YB+and+Wambebe%2C+C+and+Adachi%2C+Y++(2007)+Survivability+of+Salmonella+typhimurium+L1388+and+Salmonella+enteritidis+L1225+under+stressful+growth+conditions.++%5BJournal+(On-line%2FUnpaginated)%5D+++++&rft.relation=http%3A%2F%2Fcogprints.org%2F5847%2F