000			03355cam a2200349 a 4500
003			EG-GiCUC
005			20250223031620.0
008			161129s2016 ua dh f m 000 0 eng d
040			_aEG-GiCUC _beng _cEG-GiCUC
041	0		_aeng
049			_aDeposite
097			_aPh.D
099			_aCai01.10.10.Ph.D.2016.Ah.A
100	0		_aAhmed Mohamed Attia Elhamaky
245	1	0	_aApplication of molecular biological techniques for detection of mycotoxigenic fungi and characterization of genes responsible for toxin production / _cAhmed Mohamed Attia Elhamaky ; Supervised Heidy Mohamed Shawky , Mohamed Kamal Refai , Atef Abdelaziz Hassan
246	1	5	_aاستخدام طرق البيولوجيا الجزيئية في الكشف عن الفطريات المفرزة للسموم وتحديد الجينات المسئولة عن افراز تلك السموم
260			_aCairo : _bAhmed Mohamed Attia Elhamaky , _c2016
300			_a219 P. : _bcharts , facsimiles ; _c25cm
502			_aThesis (Ph.D.) - Cairo University - Faculty of Veterinary Medicine - Department of Microbiology
520			_aA total of one hundred feed samples were collected from Cairo and Giza Governorates and screened for aflatoxin producing and ochratoxin producing fungal isolates. A total of 106 fungal isolate comprising, Aspergillus flavus, A. ochraceus and A. niger were recovered from feed samples and tested for aflatoxins and ochratoxin A (OTA) production. The most predominant isolate was A. flavus, which was recovered at the range of (40-55%), followed by A. niger (30-50 %) and A. ochraceus (15-20%). Thirty three of 47 A. flavus isolates produced aflatoxin B1 and B2 at an average levels of (170-750 ppb), while, 22 of 44 tested isolates of A. niger produced OTA with an average levels of (100-550 ppb), whereas 12 of 15 A. ochraceus isolates produced OTA at average levels of (300-700 ppb). Molecular identification of 16 toxigenic fungal isolates (5 A. flavus, 6 A. ochraceus and 5 A. niger) was carried out by PCR. The results of PCR of the DNA extracted from these isolates using ITS primer confirmed the identification of A. flavus, A. ochraceous and A. niger. The application of real-time PCR (RT-PCR) system directed against the nor-1 gene of the aflatoxins biosynthetic pathway was applied on the DNA extracted from the 5 selected strains of A. flavus. The amplification plot of the DNA samples indicated the presence of nor-1 gene in all aflatoxins-producing A. flavus isolates and in only one isolate of the negative aflatoxins-producing A. flavus. On the other hand, the use of primer set for amplification of omtB gene responsible for AF production amplified 611 bp fragments bands in all aflatoxigenic A. flavus, while, no band was detected in all negative aflatoxigenic isolates. All the sequenced A. flavus isolates were confirmed to belong to A. flavus species and were 100% similar to the reference isolates of A. flavus
530			_aIssued also as CD
653		4	_aOchratoxigenic
653		4	_aPCR
653		4	_aSequencing
700	0		_aAtef Abdelaziz Hassan , _eSupervisor
700	0		_aHeidy Mohamed Shawky Aboelyazeed , _eSupervisor
700	0		_aMohamed Kamal Refai , _eSupervisor
856			_uhttp://172.23.153.220/th.pdf
905			_aNazla _eRevisor
905			_aSoheir _eCataloger
942			_2ddc _cTH
999			_c58826 _d58826