Isolation and identification of nocardia spp. from soil emphasizing on development of highly producing antimicrobial and antitumor strains

العناوين الأخرى

عزل و تشخيص أنواع nocardia من التربة و التأكيد على تحسين السلالات ذات الإنتاجية العالية للمضادات الميكروبية و السرطانية

مقدم أطروحة جامعية

Badi, Inas Abd al-Sahib

مشرف أطروحة جامعية

al-Sulami, Amin Abd al-Jabbar
Mahdi, Kawthar Hawwaz

الجامعة

جامعة البصرة

الكلية

كلية التربية العلمية

القسم الأكاديمي

قسم علوم الحياة

دولة الجامعة

العراق

الدرجة العلمية

دكتوراه

تاريخ الدرجة العلمية

2011

الملخص الإنجليزي

-One hundred and sixty nine Nocardia isolates were recovered from 111 samples from Iraqi soils by paraffin baiting and dilution techniques on six cultivation media including Glucose-asparagine agar, Sabouraud dextrose agar, Glycerol agar ,Nutrient agar , Modified Czapeks agar and Yeast extract agar.

The range of physical and chemical parameters of soil samples were determined including temperature (21- 49.6°C),pH( 7.1-8.1), salinity (1.03- 53.27 ppt) and calcium carbonate (0.65-12.22 mg/L).

The paraffin baiting technique was more efficient in the isolation of Nocardia than dilution technique and GAA medium was more suitable for cultivation of Nocardia isolates followed by SDA medium.

All recovered isolates were submitted to primary screening of antibacterial activity on the basis of diameters of inhibition zones against the test organism Staphylococcus aureus NCTC6571(16-55mm) and Escherichia coli ATCC 25922 (16-38mm).

The soil from north of Iraq was the richest in its content of Nocardia isolates. Eleven isolates with the highest antimicrobial activities were selected for chemotaxonomic studies revealing the following : N .sp.1, N.sp.

2 ,N .

sp.

3 , N.

sp.4 , N.

sp.5, N.sp.

6 , N.

sp.7 , N.

sp.8 , N.

sp.9 , N.

sp.

10 and N.

sp.

11 which had mycolic acid with ( Rf 0.9) . N.sp.6 was chosen out for extraction processes due to its highest inhibition zone (mm) against different standard and clinical species of bacteria and yeasts during the secondary screening . Test for the physiochemical properties of extract such as Gas Chromatography/Mass spectroscopy and Thin layer chromatography indicated that this extract was composed of 12 compounds namely beta Sitosterol, o-hydroxycinnamic acid, Eugenol, Alfa ethynylbenzyl alcohol , 3H-Pyrazol-3-one,2,4-dihydro-4,4,5-trimethyl , 1-(3-Hydroxy- 4-methylphenyl)-1,3,3,6-tetramethylindan-5-o1, 1-pentanol-2-methyl, 3-aminophenol, 4-pyridinol, 3,5-bis(1,1-dimethyl)-1,2-Benzenediol, 1-(2-Hydroxy-4,6-dimethoxyphenyl)but-2-en-1-on and Glycidol. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined against eight standard and clinical isolates of bacteria and yeasts .

The cytotoxicity effect on human red blood cells of the extract was studied and the median lethal dose (LD50) for laboratory mice showed that it was not toxic in all concentrations studied ( 8 , 10 , 14 , 16 , 18 , 20 , 24 , 40 , 60 , 80 , 140 , 200, 500, 1000, 10000, 20000 mg/Kg).The extract also showed antitumor activity against L20B mouse cell lines with highest inhibition rate of 77.1% in the concentration 6.25 mg/mL.

. The production of the extract from wild isolate N.sp.6 0.74 g/L was developed for maximum production by mutation with gamma radiation for different periods of time(1,5,15,30,45 min.) and with nitrosoguanidine at different concentrations (100,200,300,400,500 μg/L).This led to increase in production to 4.05 g/L and 20.8 g/L respectively. Improvement of fermentation medium by the addition of either 1%paraffin, 0.05%K2HPO4, 2.5%,3% glycerol, 2% glucose or 2%sucrose increased production to 8.68, 7.46, 4.26, 1.13, 5.13 and 1.33g/L respectively by N.sp.6.

. The extract production from mutated strains N.sp.6G and N.sp.6GN growing in improvement fermentation medium was calculated .

Growing of N.sp.6G in fermentation medium with 1% paraffin and 0.05% K2HPO4 increase the production to19.5 and 31.7 g/L respectively but growing of N.sp.6GN in fermentation medium with1% paraffin and0.05% K2HPO4 decreased the production to 14.6 and 17.4 g/L respectively .

التخصصات الرئيسية

الأحياء

الموضوعات

• الأدوية

عدد الصفحات

182

قائمة المحتويات

• APA
• MLA
• AMA

لغة النص

الإنجليزية

نوع البيانات

رسائل جامعية

رقم السجل

BIM-317095