Vol. 10, July, 2001.

1/10  COMPARATIVE EFFECTS OF STIMOFORT AND

NUTRI-LEAF FOLIAR FERTILIZERS ON THE MUTAGENIC

POTENTIALITY OF FENOBUCARB INSECTICIDE

H.Z. Hassan

Botany Dep., Fac. Sci., Ain Shams Univ., Cairo, Egypt

The mutagenic effects of fenobucarb insecticide and the two foliar fertilizers stimofort and nutri-leaf have been investigated on Allium cepa L. and Viciafaba L. plants. The repair effects of the two fertilizers on the mutagenic effects of fenobucarb has been also investigated. A hattary of three monitoring systems have been utilized including mitotic cell division of Allium cepa L. root tips and meiotic cell division of Vicia faba L. flower buds as well as SDS-electrophoretic profiles of the M? seed storage proteins of the treated Viciafaba L. plants. A forth monitoring system based on RAPD-PCR analysis has been used to identify the mutagenic potentiality of the tested insecticide at the genomic DNA level of the treated Viciafaba L. plants. A drastic reduction in mitotic activity was induced after different treatments with fenobucarb insecticide. A considerable ferquency of chromosomal abnormalities were also recoded after all treaments with fenobucarb insecticide in both mitotic and meiotic cell divisions. The recorded values were increased by increasing both the concentration and the time of treatments in almost all the different cytological tests. The results indicate the safety of the two fertilizers stimofort and nutri-leaf and revealed their repair effect against fenobucarb insecticide at cytological level only, especially following short periods of treatments only. At SDS-protein level the studied insecticide shows many alterations in the M2 seed storage protein banding patterns expressed as disappearance of some bands or appearance of novel ones or changes in band's intensity. Both fertilizers under study had no repair effect on these protein profile alterations. At the DNA level, RAPD-PCR analysis revealed many alterations in the DNA profiles of Vicia faba seedlings after treament with fenobucarb insecticide.

2/10  OPTIMIZATION OF THE INDUSTRIAL PRODUCTION OF BACTERIAL ALPHA AMYLASE IN EGYPT. II. ROLE OF PHYSIOLOGICAL FACTORS IN PRODUCTIVITY BY TWO STRAINS OF BACILLUS SUBTILIS AND BACILLUS AMYLOLIQUEFACIENS

O. El-Tayeb, A. Hashem*, F. Mohammad**, M. Aboulwafa***

Microbial Biotechnology Center, Faculty of Pharmacy, Cairo University

Kasr El-Aini street, Cairo, Egypt, 11562

*Dept. of Microbiology and Immunology, Faculty of Pharmacy, Cairo University

**Dept. of Chemical Engineering and Pilot Plant, National Research Centre

***Dept. of Microbiology and Immunology, Faculty of Pharmacy, Ain Shams University

This is a report on the different physiological factors affecting alpha amylase production by an improved industrial B. subtilis strain (strain S) and a new B. amyloliquefaciens isolate (strain 267). The two strains produced alpha amylase in the presence of an inducer such as starch. Although glycogen or dextrins were more efficient inducers at low concentration (0.4%), higher concentrations of starch were efficient and supported better growth. Addition of glucose to the production medium inhibited productivity in both strains. The production occurred efficiently at 37°C. No significant increase in productivity was noted by addition of any single amino acid. Both ammonium phosphates and other tested ammonium salts potentiated alpha amylase production. Cations such as Fe+++, Zn++ andCu++ inhibited production while Ca++. and Mg++ stimulated enzyme production. Although certain surfactants and polyethylene glycols increased enzyme production, their incorporation is not preferred as they produce excessive foaming. The effect of peptone, beef extract, casamino acids and yeast extract increased Pmax for both alpha amylase and protease with both strains with a delay in the time necessary to attain Pmax in most cases. This increase was also related to the concentration applied in most cases. The productivity in designed multiprotein-mineral media resulted in maximum yield of about 3.03xl04 U/ml in case of B. subtilis and of about 4.61x 104 U/ml in case of B. amyloliquefaciens after 144 h with both strains with minimal sporulation. In both strains, the enzyme production occurred in logarithmic and post-logarithmic growth phases and maximum consumption of starch and protein occurred during the first day of incubation.

3/10  OPTIMIZATION OF THE INDUSTRIAL PRODUCTION OF BACTERIAL ALPHA AMYLASE IN EGYPT. III. PRODUCTION IN SOLID STATE FERMENTATION AND ON NATURAL PROTEIN SOURCES BY TWO STRAINS OF BACILLUS SUBTILIS AND BACILLUS AMYLOLIQUEFACIENS

O. El-Tayeb, A. Hashem*, F. Mohammad**, M. Aboulwafa***

Microbial Biotechnology Center, Faculty of Pharmacy, Cairo University

Kasr El-Aini street, Cairo, Egypt, 11562

*Dept. of Microbiology and Immunology, Faculty of Pharmacy, Cairo University

** Dept. of Chemical Engineering and Pilot Plant, National Research Centre

*** Dept. of Microbiology and Immunology, Faculty of Pharmacy,

Ain Shams University

Production of alpha amylase by nitrosoguanidine-induced mutants ofB. subtilis (SN) and of B. amyloliquefaciens (267N) using solid state fermentation technique increased the productivity per unit weight or unit volume when compared to production in shake flasks. The yield by either strain reached about 62x1O4 units per gram medium compared to 4.14xl04 and 5.15 x 104 U/ml for mutants SN and 267N respectively in shake flasks. On the other hand, submerged liquid fermentations using amplified variants of B. subtilis (SCH) and of B. amyloliquefaciens (267CH) were conducted in shake flasks using either of 'several natural protein sources in powder form (defatted soya bean, defatted sieved cotton seed cake, lentil, sieved fava bean, cow-peas, kidney bean or chick-peas). Different natural protein sources showed good production of alpha amylase to various extents. Fava bean and cow peas almost doubled productivity by strain SCH while defatted soya bean powder and cotton seed cake increased the yield up to approximately 50% in case of strain 267CH when compared to conventional complex protein sources (peptone, beef extract and yeast extract).

4/10  INTRACELLULAR FATE OF CADMIUM IN PLEUROTUS OSTREATUS

I.M. El-Refai and S. Asswah

Botany Department, Faculty of Science, Tanta University, Tanta, Egypt

Pleurotus ostreatus was collected from area polluted with Cd at (Gharbia-Governorate, Egypt). It showed tendency to tolerate high cadmium concentration in the form of CdCl? up to 3.0%(W/V). The presence of cadmium in media cultivated with P.ostreatus showed the increase of the contents of cellular proteins, carbohydrates and lipids. However, (0, O.I, 0.5, 1.0, 1.5, 2.0 and 3.0 % (W/V) of cadmium showed inhibitory effect on mycelial dry weight. The degree of inhibition was dependent on the CdCl2 concentration. The presence of cadmium induced the biosynthesis of several types of low molecular weight proteins. Results suggested the accumulation of high levels of cadmium-chelators in Pleurotus ostreatus and demonstrated different modes of cadmium detoxification.

5/10  SOME PHYSIOLOGICAL AND CYTOLOGICAL STUDIES ON THE EFFECT OF IONS OF SOME HEAVY METALS ON PISUM SA TIVUM PLANT

II. Comparative Evaluation of the Effects of Ni, Cr and Pb Ions on Carbohydrates, Nitrogen Metabolism and Activities of Certain Hydrolytic Enzymes in Cotyledons and Embryonal Axes of Two Cultivars ofPisum sativum Seedlings.

M. Abd El-Hamid, A. El-Nahas and A.M.E. Abdel Hamid

Department of Biological and Geological Sciences Faculty of Education, Ain Shams University, Cairo, Egypt.

It was found that the contents of reducing sugars, sucrose, polysacchar ides, total sugars, amino-N, protein-N and total-N of embryonal axes of cv. B-master seedlings were mostly either highly significantly increased or inversely changed on treating the seeds with the relatively low concentrations (0.1 & 1.0 ppm) or the higher ones (10 &100 ppm) of nickel, chromium and lead ions respectively for 3 days. On the other hand, the same contents in embryonal axes ofcv. Sugary seedlings showed mostly substantial high significant reductions with all concentrations applied. After 6 days of treatment, these contents showed mostly either non-significant change or sharp high significant reductions in embryonal axes of cv. B-master or cv. Sugary seedlings respectively. Total soluble-N content was found to be mostly highly significantly reduced or non-significantly changed with most of the concentrations used in embryonal axes ofcv. B-master seedlings whereas it showed high significant increase with all concentrations used in the same part ofcv. Sugary seedlings. In most if not all cases, the contents of the preceding carbohydrate and nitrogen fractions in cotyledons of the seedlings of both cultivars underwent a manner of change opposite that occurred in embryonal axes. The induced changes in reducing sugars and amino-N contents in cotyledons and embryonal axes of both cultivars were found to be directly proportionated to the corresponding changes in fi-amylase and protease activities whereas those of sucrose, polysaccharides and protein-N contents were shown to be inversely proportionated to the corresponding changes in invertase, a-amylase and protease activities respectively. Ribonuclease activity in the embryonal axes ofcv. B-master and cv. Sugary seedlings underwent a pattern of change parallel to that of protease activity. In the cotyledons, the activity of the same enzyme was shown to be changed in a manner opposite to that induced in embryonal axes.

6/10  SOME PHYSIOLOGICAL AND CYTOLOGICAL STUDIES ON THE EFFECT OF IONS OF SOME HEAVY METALS ON P1SUM SA TIVUM PLANT

III. Changes in Endogenous Phytohormones and Activities of Certain Oxidative Enzymes of cv. B-master and cv. Sugary Seedlings as Influenced by Pre-emergence Treatment of the Seeds with Ni, Cr and Pb Ions.

M. Abd El-Hamid, A. El-Nahas and A.M.E. Abdel Hamid

Department of Biological and Geological Sciences Faculty of Education, Ain Shams University, Cairo, Egypt.

It was found that the contents and activity levels ofindolic auxin compounds, gibberellins and cytokinins of cv. B-master seedlings were found to be either substantially increased at the relatively low concentrations used of various heavy metal ions (O.I, 1.0 & 10 ppm) for 3 days, or highly reduced at the highest concentration applied (100 ppm) with concomitant increases in the contents and activity levels of the growth inhibitors. On the other hand, the contents and activity levels of the preceding growth hormones in cv. Sugary seedlings were shown to be sharply reduced with most, if not all, the concentrations used of the same heavy metal ions. Such induced reductions were accompanied by substantial accumulation of the growth inhibitors of phenolic nature particularly ABA and unsaturated lactones. After 6 days of treatment, the contents and activity levels of auxins, gibberellins and cytokinins of cv. B-master seedlings were found to either increased at the lowest concentration used (0.1 ppm) or decreased at the higher ones (1.0, 10 & 100 ppm) respectively with concomitant maintenance of significant IAA, IAN, GAj and active cytokinin compounds. On the contrary, the same endogenous growth hormones ofcv. Sugary seedlings showed sharp reductions coupled with the disappearance of IAA, IAN, GAj and active cytokinins whereas the growth inhibitors were substantially accumulated. The activities of lAA-oxidase, polyphenol-oxidase andperoxidase of both cotyledons and embryonal axes of cv. B-master seedlings were found to be reduced whereas that of catalase was markedly increased in most if not all various heavy metal treatments. On the other hand, the activities of the same enzymes in cotyledons and embryonal axes of cv. Sugary seedlings underwent a manner of change versus those in cotyledons and embryonal axes ofcv. B-master seedlings.

7/10  FAS SIGNALING SYSTEM MEDIATES CADMIUM-INDUCED TESTICULAR APOPTOSIS IN RATS. THE POSSIBLE PROTECTIVE ROLE OF SELENIUM

W.M. Awara*, N.E. El-Ashmawy**, S.O. Nassar*** and S.M. Talaat****

Departments of Pharmacology &Toxicology*, Biochemistry**, College of Pharmacy,

Dermatology&Venereology***, College of Medicine, University of Tanta,

Pathology****, College of Medicine, University of Cairo, EGYPT.

Apoptosis occurs in the testis as an important physiological mechanism to limit the number of germ cells in the seminiferous epithelium. Fas system was considered as a key regulator of spermatogenesis. Fas (APO-1, CD95), a transmembrane receptor protein, transmits an apoptotic signal within cells when bound by Fas ligand (FasL). The involvement of Fas system in germ cell apoptosis was assessed. This study was designed to examine whether Fas/FasL system is involved in mediating testicular tissue apoptosis in male rats by using environmental pollutants such as cadmium (Cd) as a testicular injury (toxicant) model. The possibility that selenium supplementation might prevent these testicular effects was also examined. Male albino rats were treated with CdCh (0.5 mg/kg, i.p., daily for 5 weeks). The typically apoptotic DNA fragmentation (analyzed by gel electrophoresis and ELISA programmed cell death detection) and the associated testicular histopathologic changes that induced by Cd treatment were suppressed by concurrent treatment of rats with selenium (sodium selenite;! mg/kg, i.p., daily for 5 weeks). The expression of Fas/FasL in the testicular tissues of rats after chronic Cd exposure was described. Cadmium exposure significantly increased the expression ofmRNA of FasL (assessed by reverse transcriptase- polymerase chain reaction) in rat testis as well as the number of Fas positive germ cells (assessed by immunohistochemistry). This up-regulation of Fas/FasL expression in the testis was also suppressed in rats treated with both cadmium and sodium selenite. In addition, treatment of rats with selenium prevented the accumulation of Cd in the testes as measured by atomic absorption spectroscopy. These results indicate that: (1) Chronic cadmium exposure induced germ cell apoptosis in male rats that may lead to suppression of spermatogenesis and subsequently infertility; (2) The up-regulated Fas-signaling system is involved in stimulating testicular apoptosis; (3) Selenium supplementation was effective in preventing Cd-induced apoptotic responses possibly via suppressing Fas/FasL system. In conclusion, our results may suggest that Cd-induced DNA damage and testicular apoptosis are partly mediated by Fas signaling system, and selenium is able to interrupt this molecular process of apoptosis.

8/10  BATCH AND FED-BATCH FERMENTATIONS FOR GLUCOAMYLASE PRODUCTION BY ASPERGILLUSAWAMOR1

M.M.M. Aboulwafa

Department of Microbiology and Immunology, Faculty of Pharmacy, Ain-Shams

University, Cairo, Egypt

Batch fermentations for glucoamylase production by Aspergttlus awamori using sporulated inoculum at two agitation levels of 300 and 600 rpm resulted in maximum enzyme productivities of 8,733 and 13,720 U/ml respectively. Doubling agitation to 600 rpm shortened the lime for maximum glucoamylase productivity to 45 h instead of 100 h at 300 rpm. In addition, specific glucoamylase production, specific glucoamylase production rate and glucoamylase production rate increased to much higher values upon doubling agitation. Batch fermentations under uncontrolled pH and under controlled pH at 3 and 5 resulted in maximum glucoamylase productivities of 37,242; 21,001 and 13,720 U/ml respectively. The corresponding times for maximum enzyme productivities were 58, 68 and 45 h respectively. Specific glucoamylase production, specific glucoamylase production rate and glucoamylase production rate were higher under uncontrolled pH than those under pH control at 3 and 5. Fed-batch fermentation using sporulated inoculum and feeding with starch alone did not improve glucoamylase productivity. In contrast the use of starch-multiprotein mixture as the feeding substrate improved enzyme productivity and under the feeding regimen of 83 ml/hfor 21 h followed by 47 ml/hfor 48 h the maximum glucoamylase productivity reached 51,436 U/ml after 109h. In the presence of1% glucose the maximum glucoamylase productivity of fed-batch fermentation under the feeding regimen of 70 ml/hfor 40 h followed by 160 ml/hfor 7.5 h was 18,891 U/ml. Fed-batch fermentation using mycelial inoculum at an inoculum size of 10% V/V and feeding with starch-multiprotein mixture at two different feeding regimens resulted in maximum glucoamylase productivity of not more than 32,000 U/ml with either feeding regimen. Fed-batch fermentation using 2.5% V/V mycelial inoculum and feeding with double strength starch-multiprotein mixture at feeding rates of 210, 136 and 42 ml/hfor 9, 10.5. and 16 h respectively resulted in a maximum productivity of 77,123 U/ml after 64 h. The protease(s) produced by the applied strain did not exceed 13 U/ml under the different tested conditions.


9/10  ALLELOPATHIC EFFECTS OF CYANOBACTERIAL EXUDATES ON SOME METABOLIC ACTIVITIES OF CYNARA CARDUNCULUS SEEDS DURING GERMINATION.

S.E. Saffan Botany

Department, Faculty of Science, Zagazig University

The allelopathic effects of cyanobacterial exudates on some biochemical constituents of cardoon (Cynara cardunculus) has been studied. Quantitative analysis of cyanobacterial exudates revealed the presence of phytohormones, amino acids, total soluble nitrogen and total reducing sugars that might be implicated as allelochemical agents. The results obtained show that the treatment with algal exudates of Nostoc muscorum, Nostoc piscinale and Anabaena fertilissima stimulated the germination rate of cardoon seeds after 96 hours, which reached about 100%, 98% and 98% of the control respectively. Total amino acids were greatly affected by different algal exudate treatments. Total soluble sugar and protein contents were highly significant increased in germinated seeds treated with algal exudates of Nostoc piscinale, Anabaena fertilissima and Nostoc muscorum. Such accumulation was accompanied by a increase in the levels ofamylolytic activity, while protolytic activity decreased. Similarly, the higher level of unsaturated fatty acids fraction in germinated cardoon seeds treated with algal exudates of Anabaena fertilissima, Nostoc muscorum and Nostoc piscinale was accompanied by higher levels of hpoiytic activity. These results revealed that at every reduction in the total saturated fatty acids there was a regular increase in the unsaturated ones, especially those treated with Anabaena fertilissima, Nostoc muscorum followed by Nostoc piscinale. Under the previous application with different cyanobacterial exudates, results of enzymatic activities evoked that there are an obvious stimulation in the peroxidase, catalase and phenol oxidase activities, as well as total phenolic compounds while, free phenolic compound decreased a corresponding control ones. In regards to, increases level of phenolic compounds attributed with enhancement of aromatic protein amino acidphenylalanine in germinated Cynara seeds treated with algal exudates of Nostoc piscinale, Anabaena fertilissima and Nostoc muscorum.

10/10  MICROFUNGI CONTAMINATED COTTON-FABRICS AND THEIR METABOLIC ROLE IN BIODETERIORATION.

E.M. El-Morsy*, H. El-Saht, S.M El-Dohlob and MM. EL-Metwally

Botany Department, Mansoura Faculty of Science, Mansoura University,

Mansoura, Egypt.

*Botany Department, Damietta Faculty of Science, Mansoura University, New Damietta, PO. Box. 34517-30 Egypt.

Fungi contaminated cotton materials (native, blinded, stained, stored and deteriorated) were investigated. Thirty-three species were isolated from 34 textile samples at 28°C and 45°C. A. niger, Ch. globosum, St. chartarum, A. petrikii and A. oryzae were isolated very frequent at 28°C whereas A. fumigatus and Th. Lanuguinosus were also isolated frequently at 45°C. Isolated fungi were affected significantly by changes in pH and moisture content oj textiles. Isolated species were physically affecting the toughness of the textiles by reducing its tensile strength. The most active species were St. chartarum, Penicillium purpurogenium, Ch, globosum, Ulocladium atrum and Th. Lanuguinosus. These fungi were also affecting the chemical nature of textiles by the production of cellulose degrading enzymes (exo-B-1,4 gluconase endo-B-1,4 gluconase and B-1,4 glucosidase). The activity reactions •were carried out at liquid and solid state fermentation. The activity of endogluconase and exogluconase was very small in solid state comparing to that in liquid state fermentation. Activity of cell associated B-glucosidase was very high in both states comparable to the other enzymes. The highest level of enzyme activity was shown by Penicillium purpurogenium in liquid and solid state fermentation.

11/10  BIODESULFURIZATION OF ORGANOSULFUR COMPOUNDS BY RHODOCOCCUS RHODOCHROUSIGTS8

MA. Abo-State; N.Sh. El-gendy*; LA. Farahat*; Y.M.M. Mostafa*

and SA. El-Temtamy*

National Center for Radiation Research and Technology, Nasr City,

Cairo, Egypt.

*Egyptian Petroleum Research Institute (EPRI), Nasr City, Cairo, Egypt.

In Egyptian crude oils the sulfur content ranges between (0.4-3.33wt. %). Sulfides and thiophenic compounds are the main sulfur types present in local crude oils. Rhodococcus rhodochrous IGTS8 (ATCC 53968) was used to desulfurize different organosulfur compounds that were believed to exist in crude oils in a test called sulfur bioavailability assay, which showed the ability to desulfurize an extremely broad array of organosulfur compounds as a sole source of sulfur, including thiophenes (Thiophene (Th), 2-Acetylthiophene (2At), Benzothiophene (BT), Dibenzothiophene (DBT), Dibenzothiophene sulfoxide (DBTO), Dibenzothiophene sulfone (DBTOz)), sulfoxides (Dimethyl sulfoxide (DMSO)) and Methyl sulfonyl chloride (MSC). Investigation of the byproducts effects on BDS of 0.1%DBT showed the medium sulfate requirements for bacterial growth was about 0.25-0.5mMand the presence of such amount enhances biodesulfurization (BDS) by allowing more vigorous growth. However, higher levels of sulfate (>0.5mM) inhibit the growth and consequently inhibit the desulfurization of DBT and 2-HBP production. Accumulation of2-HBP generally inhibits growth and desulfurization.

12/10 AMELIORATIVE EFFECT OF CaCl2 ON NaCl STRESSED

VICIA FABA L. PLANT GROWTH AND ACCUMULATION OF

SOME OSMOREGULATORS.

A.A. Fathy

Botany Department, Faculty of Science, Alexandria University, Alexandria, Egypt.

The present work was conducted to elucidate the excess, external Ca++ concentration potentiality to ameliorate the deleterious effect of excess Na concentration on Vlcia faba plant. Vicia faba seeds were grown under different stresses of NaCL levels (up to 200 mM NaCL) alone, and in combination with different CaCL2 concentrations (5 and 10 mMCaCLi).All growth parameters (fresh and dry weight, and photosynthetic pigments) were adversely affected by increasing NaCL level. Chlorophyll a was greatly affected more than other photosynthetic fractions, Total free amino acids andproline were accumulated with the increase of NaCL level. The increase was higher significantly in shoot than in root system. On contrary, the protein content in both root and shoot systems exhibited an obvious decrease, especially at NaCL level of 200 mM. Root system seemed to be much affected than shoot system, concerning protein content. The total soluble carbohydrate contents increased significantly in both root and shoot systems with the increase of NaCL level. Accumulation of carbohydrate content was much higher in shoot than in root. Addition ofCaCL2 in the saline growth medium enabled Vicia faba to withstand severe conditions of salt stress up to 200 mM external sodium chloride concentration. All growth parameters showed a great enhancement by the addition of CaCL} into the saline growth media. Finally, it can be concluded that exogenous application oj CaCL^ alleviates the inhibitory effect of NaCL on Vicia faba plant growth, within the studied range.

13/10  POTENTIALITY OF SOME EGYPTIAN RHODOPHYCEAN SEAWEEDS LECTINS FOR HEMAGGLUTINATION OF DIFFERENT HUMAN BLOOD

ERYTHROCYTES AND THEIR TAXONOMIC VALIDITY

A.A. Fathy and N.A. Mohamed*

Botany Department, Faculty of Science, Alexandria University.

*Zoology Department, Faculty of Science, Alexandria University.

The red seaweeds Laurancia pinnitifida, Gigartina teedii, Gelidium crinale, and Pterocladia capillacea, were analyzed for their hemagglutination ability against different human blood etythrocytes and their chemical composition. There was notciable variation in their hemagglutination activity along different seasons. On the other hand, their chemical composition regarding their agar, protein, total lipid, and carbohydrate contents varied greatly along four seasons. There was no clear correlation between hemagglutination ability and their chemical composition for studied algal species. Laurancia pinnitifida showed the greatest ability for agglutination the erythrocytes of four human blood groups even at short time period (20 nun). Moreover, this species is the only the species which has the ability to agglutinate blood group "A". All other species have succeeded to agglutinate blood group "O". According to the variability in hemagglutination ability of the studied seaweeds, it was possible to differentiate between different human blood groups.

14/10  ISOLATION AND CHARACTERIZATION OF TWO TYPES OF ACTINOPHAGES INFECTING STREPTOMYCES

SCABIES MR13

E.A. El-Sayed, G. El-Didamony and K. Mansour

Department of Botany, Faculty of Science, Zagazig University, Zagazig, Egypt

Two types of actinophages, фS and фL, could be isolated from soil samples by using Streptomyces scabies MR13, a potato scab pathogen, as an indicator strain. The phages were partially characterized according to their physicochemical properties, plaques and particles morphology, and their host-range. The host-range of these phages varied from narrow (for ф5) to wide host (for фL). The adsorption rate constants of the фS and фL were 3.44 x 10-9 and 3.18 x 10-9 ml/min, and their burst sizes were 1.61 and 3.75 virions/ml, respectively. One-step growth indicated that 0S and $L have a latent period of 30 min followed by a rise period of 30 min. The temperate character of these phages was tested in other isolates of Streptomyces. However, four of the phages (фSS3, фSS12, фSS13 and SSI 7) were identified as temperate phages, since they were able to lysogenize SS3, SSI 2, SSI 3 and SSI 7. фSS3, фSS12 and фSS13 were homoimmune, and they were heteroimmune with respect to фSS17. The restriction barriers of lysogenic isolates (SS12, SS13 and SS17) interfered with the blockage of plaques for motion by phages (фSS12, фSS13 or фSS17) propagated on them, about 75% of lysogenic isolates had a restriction systems. The exposure of the lysogenic isolates (SS12, SS13 and SS17) to UV-irradiation, where longer irradiation decreased the number of viable cells.

15/10  SOME PHYSIOLOGICAL ROLES OF JASMONIC ACID IN ADAPTATION OF PEA SEEDLINGS TO SALT STRESS

S.M. El Khallal

Department of Botany, Faculty of Girls, Ain Shams University,

Cairo, Egypt

Jasmonic acid has been shown to play an important role in plants under salt stress. Pretreatment of pea seedlings with different concentrations ofJA (0.5, 1.0 and 5.0 /nM) for 3-days before salinization with NaCl at concentrations (50, 100 and 150 mM) can alleviate or retard the harmful effect of salinity on growth and metabolism of pea seedlings. JA helps the pea seedlings to counteract the salt stress by enhancing the accumulation of osmotically active solutes, soluble sugars, soluble proteins, total free amino acids, free proline, as well as decreasing Na+ and Cl~ ions accumulation, thus JA induced salt tolerance and partially increased capacity of osmoregulation in seedlings. On the other hand, SDS-PAGE analysis revealed that JA with or without NaCl markedly induced novel proteins which were identical to jasmonate - induced proteins (JIPs) ofMwt(183, 103, 95, 93, 77.8, 66.0, 50.8, 45.5, 36, 35 .0, 23.0, 21, 16.5, 14.5, 11.5, 8.0, 6.5 and5.5 KDa), also, other salt novel proteins of M wt (95, 66,50.8, 44,38, 23 and 16.5 KDa) were accumulated in pea seedlings treated with NaCl. JIPs were accumulated in pea seedlings treated with JA are anticipated to play an active role in salt tolerance through a variety of functions in cells. Also, data revealed that JA counteracted the toxic salinity effect by increasing the concentrations of endogenous growth hormones (ABA, IAA, GAj and cytokinines) in pea seedlings pretreated with JA before salinization in comparison with the corresponding control treated with NaCl. Also, JA induced - salt tolerance in pea seedlings by increasing the activities of antioxidant enzymes (Peroxidase — Cat alas e and Glutathione reductase) which take part in the final generation of the JA - induced salt tolerance.

16/10  MODEL MICROBIAL DESULFURIZATION OF

DIBENZOTHIOPHENE USING RHODOCOCCUS

RHODOCHROUSIGTS8

N.Sh. El-gendy, L.A. Farahat, M.A. Abo-State*, Y.M.M Mostafa,

and S.A. El-Temtamy

Egyptian Petroleum Research Institute (EPRI), Nasr City, Cairo, Egypt.

*National Center for Radiation Research and Technology, Nasr City, Cairo, Egypt.

Dibenzothiophenes (DBTs) and its derivatives are some of the most recalcitrant \ organic sulfur compounds to the hydrodesulfurization (HDS) of crude oil and refined transportation fuels. DBT has been used as a sulfur model compound for over a decade in research. In the present study DBT desulfurization has been performed by Rhodococcus rhodochrous IGTS8. A convenient spectrophotometric assay (Gibbs assay), was used in conjunction with high performance liquid chromatographic (HPLC) analysis under specifically developed conditions to examine DBT utilization by Rhodococcus rhodochrous IGTS8. Biodesulfurization (BDS) experiments were conducted in aqueous phase; two-phase (aqueous/paraffin oil) and non-aqueous (paraffin oil) phase. In case of aqueous phase experiments, approximately 41% of DBT was converted to 2-hydroxybiphenyl (2-HBP) after 72 hours incubation. While 60% desulfurization of DBT was observed for the aquous/paraffin oil-phase experiment. Only 20% desulfurization was observed in case of non-aqueous paraffin oil.

17/10  REQUIREMENT OF NICKEL FOR OSCILLATORIA LIMOSA

N.H. Noaman

Department of Botany, Faculty of Science, Alexandria University, Alexandria, Egypt.

All concentrations of zinc and mercury inhibit the growth, the carbohydrate content and the protein content of the alga Oscillatoria limosa, while nickel at a low concentration increased the growth, protein content and carbohydrate content of that alga. It is proposed that growth in the blue-green alga is nickle-dependant.

18/10  RESISTANCE PATTERNS, PLASMID PROFILES AND b-LACTAMASES OF CLINICAL ISOLATES OF PSEUDOMONAS

AERUGINOSA

M.F. Ghaly, E.Y. Tohamy, M.S. Abdel-Sabour**, A.A. Kadry*, M. Abou El-Hawa and A.M.A. Zaid*

Dept. of Botany, Faculty of Science, *Dept. of Microbiology, Faculty of Pharmacy,

Zagazig University and **Dept. of Genetics, Faculty of Agriculture, Moshtohor, Benha branch, Zagazig University, Egypt.

A total of 94 clinical strains as well as two standard strains of Pseudomonas aeruginosa. were tested for their susceptibility against 11/3-lactam antibiotics. All isolates were resistant to at least 6 antibiotics including: ampicillin, amoxycttlin, amoxycillin/clavulanic acid, cephalexin, cephaloridine and cloxacillin. Ceftazidime, aztreonam and/or imipenem, exhibited the highest activity with resistance rates of 2.1% and 3.1% respectively, followed by cefotaxime (14.6%) and ceftriaxone (38.5%). Isolates no. 88 and 90 were resistant to all antibiotics under investigation except imipenem. The resistant patterns of P. aeruginosa isolates were heterogenous, since as many as 8 different patterns were recognized among the tested isolates, b-lactamases from twelve mostly resistant isolates of P. aeruginosa were analyzed by isoelectric focusing (IEF). Six isolates from the twelve multiresistant P. aeruginosa isolates revealed the same pattern of f3-lactamases with isoelectric focusing point ranging from 7.5 - 8.7. However, the highest production of b-lactamases were detected in isolates no. 33, 90 and 94, these isolates revealed different resistant patterns. The same multiresistant isolates used in isoelectric focusing were screened for their plasmid profiles. The results indicated that P. aeruginosa isolates with the same plasmidprofiles showed different resistant patterns.


19/10  EXTRACTION OF BIOEMULSIFING AGENTS FROM IRRADIATED Hansenula anomala

G.A. El-Sherbeny and S.A. Melligy* Faculty of Science, Dept. of Botany Zagazig University *National Center for Radiation Research and Technology, Atomic Energy Authority, Nasr city, Cairo-Egypt -

Gamma irradiation has great effects on the yeast fungus Hansenula anomala,

as it affected, the morphology of ascospores and yeast cells by increasing the budding rate and elongation of cells. By increasing the dose of irradiation (IkGy) the percentage of total protein, carbohydrate and lipid contents were increased. The production of the bioemulsifmg agent from H. anomala was considered an important criterion in reducing subsequent downstream processing costs and to be used in food processing.

20/10  INFLUENCE OF SOME CHEMICAL COMPOUNDS AND THERMAL TREATMENT ON THE CITRININ PRODUCTION AND GROWTH OF PENIDLLIUM CITRINUM

A.A. Shindia, S.M. Ezzat, A. El-Essawy and H.M. Ammar

Department of Botany and Microbiology, Faculty of Science,

Zagazig University, Zagazig, Egypt.

Citrinin is one of the most dangerous mycotoxic compounds that cause serious diseases to human and animals. So, the control and reduction of citrinin production by P. citrinum in the synthetic medium using different chemical and physical means were very important task to be investigated. Addition of some food preservatives had inhibitory effect on citrinin production and this inhibition is inconsistent with fungal growth. Both, bibutyric and boric acids induced maximum reduction in citrinin yield when added at 2mg/ml fermentation medium. The application of volatile compounds was accompanied with decrease ofbiomass and mycotoxin production except ethanol and methanol compounds. Acetic acid was the best inhibitor volatile compound for citrinin production. It is also found that, some chemical mutagen induced an observed decrease in citrinin production. Sodium azide inhibited the fungal growth and high concentration of hydroxylamine was responsible for completely inhibition of citrinin production. In addition, the effect of thermal treatment of fungal inoculum on citrinin production and growth rate was also discussed briefly.

21/10  ENVIRONMENTAL CONDITIONS INFLUENCING CITRININ PRODUCTION BY PENICILLIUM CITRINUM AND ITS

EFFECT ON SOME ORGANISMS

A.A. Shindia*; S.M, Ezzat; A. El-Essawy and H. Ammar Department of Botany and Microbiology, Faculty of Science, Zagazig Univ., Zagazig,

The mycotoxin citrinin represents an important problem in fungal food poisoning in some countries. It has toxic effect on human, animals and plants. So far some environmental factors affecting citrinin production and its toxicity on the growth of bacteria and yeasts as well as seed germination of different crops were studied. Variable amounts of citrinin were detected in the filtrates of four Penicillium spp out of 19 tested fungal species isolated from different cereal samples. Peniciltium citrinum was distinguished by its capacity to produce citrinin when cultivated on a selected medium. Optimum growth and citrinin production by P. citrinum were achieved at 30°C and pH 5.0. One week was the optimum incubation period for growth of P.citrinum while 13 days was the best one for citrinin production. Citrinin had antimicrobial effects where, it inhibits the growth of Lactobacillus subtilis and the rate of inhibition dependent on its dose. It was found that, respiratory-deficient yeast strains were more sensitive against citrinin than a normal respiratory competent wild-type strains. In addition, the inhibitory effect of citrinin on seed germination of different crops was discussed briefly and the maximum inhibition was recorded in maize germination.

22/10  MICROBIAL DEGRADATION OF LOW-DENSITY POLYETHYLENE STARCH BLENDS

E.A. Hegazy, M.A. Abo-State*, H.A. El Rehim and A.M. Ali

Dept. Polymer Chemistry, and *Dept. Microbiology, National Center for Radiation Research and Technoloyg. Cairo, Egypt.

Low-density polyethylene (LDPE) starch blends were exposed to the effect ofU.V light and / or soil burial. Also they were exposed to the enzymatic activities of three different fungi (Asperigllus flavus, Asperigllus niger and Fusarium sp.). Changes in mechanical properties (tensile strength and elongation) had been investigated. Thermal parameter using Differential Scanning Calorimetry (DSC), Structural changes using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) for polymer blend changes were determined. SEM for changes in polymer blends due to the activities of the three fungi; A. flavus, A. niger and fusarium sp. also was investigated. The results revealed that, the tensile strength of U. V sunlight (60 days) then burial in soil for 6 months of blends reduced by 20% to 66% of initial value. Also the elongation was reduced by 70 to 100% of the initial value according to the starch content in the blends. SEM clearly showed the holes and created cavities at the surface of blends after soil burial or after exposure to the enzymatic activities of the three fungi.

23/10  FUNGICIDE REMOVAL FROM INDUSTRIAL WASTE WATER USING A NEW SAFE BIOSORPTION TECHNOLOGY.

N.M. Sidkey

Fermentation Biotechnology and Applied Microbiology, (Ferm.-BAM) Center, Al-Azhar University, Nasr City, Cairo, Egypt.

The biosorptive power of two biosorbents viz.: the ex-fermented bagasse by its own natural microflora without (BIOSORB-I) and with the dried mycelium of Rhizopus sexualis (BIOSORB-Il) has been determined for the sake ofortho phenyl phenol-based tetrahydrated (20% SOPP) removal from the industerial waste water as an organic biohazardous fungicide. Data of the introduced biosorption process were compared with data of the chemical method from one hand and that of activated carbon (as a standard absorbent) from the other hand. (Biosorb-11) followed by (Biosorb-I) exhibited remarkable improvements of the waste water quality with obvious and/or total treatments of suspended solids, pH, conductivity, TDS, BOD, COD, phosphates, nitrates, oil & grease, settleable solids, iron and aluminium comparable to the ordinary chemical method. In addition, the removal % of SOPP reached 94.2% in case ofBiosorb II, followed by Biosorb I (91.6%), activated carbon (58.45%) and chemical treatment (29.J5%) respectively. Therefore, the new introduced Biosorption technology represents a cheap, easy to do, available and effecient biosorbent for quality improvements as well as the removal of waste water contaminants including organic hazardous fungicide.

24/10  CHARACTERIZATION OF PROTEIN PATTERNS AND DNA FINGERPRINTS OF TWO EGYPTIAN BARLEY CULTIVARS DIFFERING IN SALT SENSITIVITY

F. El-Shintinawy and S. El-Fiky

Botany Department, Faculty of Science, Tanta University, Tanta, Egypt

Salt treatment (100 mM NaCl) of barley seedlings; cultivar Giza 125 increased Na content of seedling roots by about 2.7 folds while decreased their K content by \ about 0.53 fold compared to control roots. On the other hand, Na content in roots of NaCl-treated seedlings of barley cultivar Giza 123 showed only 1.9 times increse accompanied with 0.26 time decrease in K content relative to control seedlings. Consequently, the ratio of Na/K estimated in roots of NaCl-treated Giza 125 was increased twice that detected in roots of NaCl-treated Giza 123. PCR-RAPD analysis of genomic DNA extracted from control of both cultivars showed 10 major fragments which could be considered as specific for barley. In response to salinity stress, several fragments that detected in the DNA isolated from control seedlings of both cultivar s were disappeared while others were created. DNA of Giza 123 responded to NaCl treatment by the disappearance of only one fragment and initiating 3 fragments while DNA of salt treated Giza 125 lost 5 fragments accompanied with the appearance of 4 fragments. In addition. There are numerous fragments whose relative amounts increased in one cultivar while decreased in the other one, thus, could be regarded as specific for each cultivar under salinity stress. Analysis of the scanned SDS-PAGE gel proteins revealed the presence of several bands representing high molecular weight proteins and ranging between 252.4 and 115 KDa which are characteristic to control Giza 123. Analyzing patterns of proteins extracted from barley seedlings exposed to various levels of NaCl stress at 50, 100 and 200 mM showed a consistent opposite response characterizes each cultivar. A set of 6 protein bands with molecular weights in the range from 108.8 to 72.4 KDa were decreased in their relative concentrations in salt treated Giza 123 cultivar. In contrast some of these proteins were accumulated in seedlings of Giza 125 under various NaCl concentrations. On the other hand, a set of 9 proteins having molecular weights between 67.2 to 13.7 KDa were increased in their relative intensities in NaCl-treated Giza 123 compared to the control. In contrast, proteins extracted from salt treated Giza 125 seedlings showed a suppression in their relative amounts or absence of numerous protein bands having molecular weights between 91.3 and 13.7 KDa. Thus, results obtained in present study point to a possible involvement of the alterations in gene expression either by the induction or repression of some new genes or their products in the mechanism of salt tolerance of the two barley cultivar s Giza 123 and Giza 125. These changes are presently used as a genetic marker in determining the tolerance status among different plant species and or within cultivar s in order to give a clearer insight on this physiological trait.


25/10  FORMULATION AND IN-VITRO EVALUATION OF DICLOFENAC POTASSIUM CAPSULES AND TABLETS PREPARED BY TOP-SPRAY FLUID-BED

A.M.S. Ahmed, I.S. Khattab, A.A. Zaki, and M.I. Fetouh.

Dept. of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy,

Al-Azhar University, Nasr City, Cairo, EGYPT.

The objective of this study was to formulate Diclofenac potassium as capsules and tablets from their coated granules in a trial to control its in-vitro release. Different polymers in different ratios were used for coating of Diclofenac potassium in Fluidized-bed granulator-dryer. Then, the prepared capsules and tablets were evaluated for their uniformity of weight, uniformity of thickness, hardness, friability, content uniformity, disintegration time, and also the in-vitro dissolution rates were studied. Then, optimization technique was employed, viz Factorial design to investigate the effect of polymer concentrations andpH values on the in-vitro release of the drug. All Diclofenac potassium tablets prepared from coated granules using fluidized bed apparatus complied with the pharmacopieal requirements for uniformity of weight, drug content and disintegration time and they have acceptable uniformity of thickness. Mean while the prepared tablets by direct compression have showed reasonable hardness and friability values. The concentration of the polymer employed was found to be correlated negatively with both the hardness values and the disintegration times. In-vitro release of Diclofenac potassium (75mg) from the prepared capsules and tablets containing different coating polymers was investigated in two different dissolution media, at pH 1.2 and 7.4. All the prepared coated polymers used showed a marked retardation of Diclofenac potassium, which is more retarded in tablet compared to the capsule formulations. Increasing the percent of the different polymers in the prepared drug-polymer formulations, exhibited remarkable retardation of Diclofenac potassium released. The retardation effect of the different polymer used as a coat can be arranged in descending order within 7hours as follow: Surelease, mixture of Surelease and HPMC, Chitosan, mixture ofEudragit RL30D and RS30D, and Eudragit RS30D in the capsule formulae, then Surelease, Surelease and HPMC, Eudragit RL30D/RS30D, Chitosan, and Eudragit RS30D in tablet formulae. The in-vitro release of Diclofenac potassium from the different capsule and tablet formulations was found to follow Hixson crowell cube root law. The results of the experimental design technique illustrate that the decrease in X\ (polymer concentration) and increase in X^ (pH) led to the increase in percent drug released from the formulae.

26/10  CHANGES IN GROWTH, PROTEIN PATTERNS AND DNA FINGERPRINTS OF NACL STRESSED WHEAT SEEDLINGS TREATED WITH ARGININE, PUTRESCINE OR PHENYLENEDIAMINE

R. Hassanein and *F. El-Shintinawy

Botany Department, Faculty of Science, Ain-Shams University, Cairo, Egypt

*Botany Department, Faculty of Science, Tanta University, Tanta, Egypt

Exposure of 18 d old wheat seedlings to 150 mMNaCl decreased their length, fresh and dry weight (measured 12 days after treatment) by about 31, 40 and 27%, respectively relative to their corresponding controls. Application of arginine, putrescine or phenylenediamine (4 mM each) in the presence of 150 mM NaCl retained the values of the mentioned growth parameters; putrescine is the most effective. Protein profiles of NaCl-treated seedlings showed a reduction in the intensities of some protein bands or disappearance of others at molecular weights ranging from 221 to 40 KDa. Application of 4 mM of arginine, putrescine or phenylenediamine to the NaCl containing solution resulted in marked changes in the protein patterns of the seedlings relative to those detected in seedlings treated with NaCl alone. Putrescine application recovered the reduction induced under salt stress (from 15.7% in control to 6.5% in NaCl-treatd seedlings) in the band intensity at 171 KDa to 14.5%. In addition, putrescsine and phenylenediamine were unique in initiating 6 and 3 protein bands having molecular weight ranged between 55 and 34 KDa while those for arginine were newly synthesized between 39 and 35 KDa. Several control protein bands whose intensities either decreased (detected between 79 and 35 KDa) or newly induced (detected between 30 and 14 KDa) by salt treatment were intensified again by the treatment with the three modulators. PCR-RAPD analysis ofgenomic DNA using 5 primers (OPB-1, 2,9, II and 17) showed that DNA of control wheat seedlings was characterized by the presence of 5 unique fragments. However, DNA isolated from seedlings exposed to 150 mM NaCl revealed the occurrence of 7 distinct DNA fragments, interestingly, 3 of these fragments could be considered as salt specific because they have not been detected with all other treatments. DNA extracted from NaCl arginine-treated seedlings was characterized by having 4 special fragments while that isolated from seedlings treated with either putrescine or phenylenediamine had 6 distinct fragments. In addition, 3 DNA fragments could be regarded as specific for wheat Giza 163 as they were present in control seedlings as well as in those exposed to all treatments. Moreover, several fragments that present in the DNA isolated from control seedlings and disappeared with NaCl treatment were synthesized again by arginine, putrescine or phenylenediamine applications.

27/10  STUDY OF THE INFLUENCE OF EFFERVESCENCE (CARBONATION) ON GASTRIC EMPTYING RATE, PH, AND

MUCUS CONTENT

A.B. Yassin, H.H. El-Shattawy, A.A. Kassem and J.R. Robinson*

Faculty of Pharmacy, Al-Azhar University, Nasr City, Cairo, Egypt

* School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53706

Both the rate and the extent of absorption of a large number of drugs have been increased when given orally in effervescent formulations rather than their non-carbonated solution counterparts. The scope of this work is to identify some of their mechanism(s) to allow optimization of the beneficial attributes on drug absorption and to substantially improve such drug delivery system. The cannulated dog model was used following surgical implantation of a modified Thomas cannula. The rate of discharge of 50 ml solution of three effervescent mixtures (EFF I, EFFII, and EFF HI), with theoritical molar carbon dioxide concentrations of 0.67x 10-2, 1.33x10-2, and 2.00 x 10-2 respectively, were compared with their control solutions containing the same concentrations of effervescent solutes but carbon dioxide gas was eliminated by stirring for one hour. As compared to controls, the rate of gastric emptying was tremendously accelerated in the case of EFFII and EFF III while no effect was seen with EFF 1. The tl/2 (the time at which half of the administered volume is discharged) was 7.2, 7.4, and 25.8 min. for EFF III, EFF II, and EFF I, respectively. The total volume discharged was tremendously increased and volumes as high as 89.74 ml and 97.40 ml were discharged 90 min. after the respective administration of EFF II and EFF HI, which suggests thinning of the stagnant unstirred water layer and/or mucus and gastric secretions stimulation. This may also explain the significant increase in solids content of EFF II and EFF HI compared with their controls. The pH of the liquid discharge in the time period (25-45 min. post administration) was shifted almost two units lower in the case of EFF II and EFF HI.

28/10  DEVELOPMENT AND OPTIMIZATION OF SUSTAINED-RELEASE CAPTOPRIL TABLETS AND CAPSULES.

I.S. Khattab, S. Abdel-Rahman*, S.Khidr* and O. Abdel-Hakiem

Dept. of Pharmaceutics and Ind. pharmacy, Faculty of pharmacy,

Dept. of Ind. Pharmacy, Faculty of Pharmacy, Al-Azhar University, Cairo

and *Assiut. Egypt.

The purpose of this Work is to develop aNd optimize the releAse ofcaptopril froM sustained-release Floating tablets and Capsules prepared bY wet granulation emPloying afullfactoRial experimental deSign. Captopril: polymer (Hpmc 4000 and 15000) ratios of 1:1 and 2:3 in addition to Eudragit rs 100 and Rspm as granulating Agent in a concentraTion of 10 and 25% w/W in tablet or caps Ule were used to forMulate the floating Dosage forms as diet A ted by the expeRimental design. Sodium bicarbonate at a 3% w/w ratio of the Tablets or capsule Formulae was used as €02 Generating agent. Lactose was added to Adjust the weight, According to the expErimental design, grAnules were made and Compressed into tablets orfilleD in capsules up to Constant weight of 150 mg. The percent dRug release from eacti formulation was meAsured using usp appAratus ii. Response surface analysis was used to deTermine the levels oF the factors, which Yield optimum valueS of the response peRcent Drug release, also, Mathematical models Were generated betwEen the dependent anD independent variables. Formula corresponding to 2:3 captopRil: hpmc 15000 ratiO using eudragit rspMin a ratio of 25% W/w ofcaptopril in Tablet or capsule, sHowed the longesT release time, suitAble initial drug release and the most iDeal floating properTies. The tablets anD the capsules maintAined their floating Characteristics during the release studY (8 hours). The release profile From the different bAtches was found to Follow higuchi model wiTh a correlation coeFficient 0.990. An iNcrease in thepolymEr ratio resulted in A prolongation in tHe release time with A t50% ranging from 1.5 to 3 hours. The Results indicate thAt eudragit concentrAtion has little effEct on the releaSe ofcaptopril, while the critical formulation factor was tHe drug: hpmc ratio In the tablet matrix.


29/10  MECHANISTIC STUDIES ON ENHANCED INTESTINAL

ABSORPTION OF CARBONATION USING TETRACYCLINE

AND MANNITOL AS MODEL DRUGS

A.B. Yassin, H.H. El-Shattawy, A. A. Kassem and JR. Robinson*

Faculty of Pharmacy, Al-Azhar University, Nasr City, Cairo, Egypt

School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53706

The full potential of oral carbonated system has not been fully exploited and, indeed, the mechanism(s) of enhanced oral absorption have not been elucidated. Single pass in-situ rat intestinal perfusion model was used to study the effect of ejfervesence on the absorption characteristics oftetracycline, a model drug, from the duodenum and colon. The effect of the degree of carbonation on tetracycline absorption was investigated by comparing three effervescent levels EFF I, EFF II, and EFF III, having theoretical molar carbon dioxide concentrations of 0.13 x l0-2, 0.76 x 10-2, and 1.5 x 10-2, respectively, with control solution.Mucosal-serosal transport of mannitol through dudenum tissue was investigated in the presence and absence of carbon dioxide gas using a modified Ussing chamber. The mean disappearance rate of tetracyclin from the duodenal perfusate, as well as the absorption rate constant (KA) were increased significantly in the presence of EFF II and EFF III, while in the case of EFF I, no significant change was noted. Absorption of tetracyline from the rat colon is enhanced in the presence of EFF II and EFF HI. The results showed a 35% increase in apparent permeability (P°) in the case of EFF II and a 60% increase in the case of EFF III. In the presence of CO2, the percent of mannitol transported across the excised rat duodenum was almost two folds higher than the control. This may lead to the conclusion that CO2 causes opening of the tight junction which regulate absorption by the paracellular pathway.

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