تجاوز إلى المحتوى الرئيسي
User Image

Dr. rer. nat Elsayed Ahmed Elsayed

Associate Professor

Faculty Staff Member

كلية العلوم
Building 5, AB107
المنشورات
مقال فى مجلة
2015

Development of fed-batch cultivation strategy for efficient oxytetracycline production by Streptomyces rimosus at semi-industrial scale

El-Enshasy, yed Ahmed Elsayed, Hoda Gamal Omar and Hesham Ali . 2015

Oxytetracycline (OTC) production by  Streptomyces rimosus  was studied in batch and fed-batch cultures in shake flask and bioreactor levels using semi-defined medium. First, the effect of glucose concentration on OTC production and growth kinetics was studied intensively. The optimal glucose concentration in the medium was 15 g/L. Higher glucose concentrations supported higher biomass production by less volumetric and specific antibiotic production. Based  on  these  data,  cultivations  were  carried  out  at  semi-industrial  scale  15  L  bioreactor  in  batch  culture.  At bioreactor level, cell growth and OTC production were higher compared to the shake flask culture by about 18 and 38%, respectively. During the bioreactor cultivation, glucose was totally consumed after only 48 h. Thus, the fed batch experiment  was  designed  for  mono-glucose  feeding  and  complete  medium  feeding  to  increase  the  OTC production by overcoming carbon limitations. The results showed that the fed-batch culture using constant glucose feeding strategy with rate of 0.33 g/L/h pro duced 1072 mg/L. On the other hand, feeding with complete medium resulted in 45% higher biomass but less OTC production by about 26% compared to mono -glucose fed culture. A further improvement in this process was achieved in by keeping the dissolved oxygen  (DO) value at 60% saturation by  cascading  the  glucose  feeding  pump  with  the  DO  controller.  The  later  feeding  strategy  resulted  in  higher antibiotic production, reaching 1414 mg/L after 108 h.

رقم المجلد
58
رقم الانشاء
5
مجلة/صحيفة
Braz. Arch. Biol. Biotechnol
الصفحات
676-685
مزيد من المنشورات
publications

Background: Pectinase enzymes present a high priced category of microbial enzymes with many potential applications in various food and oil industries and an estimated market share of $ 41.4…

بواسطة El Enshasy, Elsayed EA, Suhaimi N, MalekRA, Esawy M
2018
publications

A series of azocompounds containing methyl salicylate 4a–k and 1-naphthyl moiety 6–8 was synthesized and tested as anticancer
agents. Nitrosation of methyl 5-amino-2-hydroxybenzoate or 1-…

بواسطة El-Naggar M, El-Shorbagi A-N, El-Naggar D, Amr AE, Al-Omar M, Elsayed EA
2018
publications

Invertase (β-D-fructofuranoside fructohydrolase; EC 3.2.1.26) constitutes an improtant microbial enzyme with wide applications in differnt food and pharmaceutical sectors. The present work used…

بواسطة Elsayed EA, El Enshasy HA
2018