Vol. 15, October, 2003.

pasteque et viagra 1/15 PRODUCTION AND CHARACTERIZATION OF KERATINASE ENZYME OF PENICILLIUM RAISTRICKII AND ITS ROLE IN NATIVE CHICKEN FEATHER DEGRADATION

S.A. Khalaf   and M.A. Khalaf*

Botany Department, Faculty of Science, Zagazig University, Egypt

*Microbiology Department, National Center for Radiation Research and Technology, P.O.Box 29, Nasr City, Cairo, Egypt

In this study, a total of 66 common fungal isolates belonging to 8 genera were isolated from chicken feather wastes, and were screened for synthesis of extracellular keratinase. Ninteen fungal isolates grew on agar plates with chicken feather soluble keratin and excreted the enzyme. siege social du viagra au canada Penicillium raistrickii was investigated as the most powerful keratinase extracellular producer. The highest keratinase production (38.6 uml-1) by this strain was observed on the tenth day of growth. The concentrated crude efficacité viagra 25mg P. raistrickii keratinase exhibited activity toward soluble keratin optimally at 50°C and pH 8.0. No inhibition of this enzyme was recorded by PMSF, but approximately complete inhibition by EDTA and EGTA was demonstrated, and it was restored by the addition of Ca+2 or Mg+2. These results indicated that boites cialis P. raistrickii keratinase is a metalloprotease with a high degree of keratinolytic activity and stability. Dry weight determination analysis revealed that 54% of the native feather meal, was hydrolysed by qu est ce que levitra P. raistrickii keratinase after the fourth day of incubation.

les contre indications du cialis  

achat de vrai viagra  

cialis pharmacie forum 2/15 ALKALINE AND ACID PHOSPHATASES ACTIVITY DURING THE INTERACTION BETWEEN MYCORRHIZA (GLOMUS FASCICULATUM (THAXTER STNSU.) GERD. AND TRAPPE) AND RHIZOBIUM LEGUMINOSARUM CULTIVAR VICIA (RH) ON THE GROWTH OF FABA BEAN.

M.M. Aly and Y.A. Mahmoud*

Biology Department, Faculty of Education, Tanta University, Kafer El-Sheikh Branch, Egypt

*Botany Department, Mycology Research Lab., Faculty of Science, Tanta University, Tanta 31527, Egypt

Physiological activity of vasicular arbuscular mycorrhiza (VAM) ( ou acheter du viagra fiable Glomus fasciculatum) alone and in combination with commander kamagra en france Rhizobium ( Rhizobium leguminosarum) was studied using acid and alkaline phosphatases, and succinate dehydrogenase in inoculated faba bean plants during the different stages of plant growth. Inoculation of faba bean plant with both endophytes was significantly increased the plant growth parameters, N, Mg, K, and P, when compared with the control, and the total level of mycorrhizal infection was not related to plant phosphorus content. Frequency of plant infection, infection intensity, and arbuscule frequency of mycorrhiza were increased during maturity stage of plant growth, but slightly in vegetative and flowering stages. Mycorrhizal growth responses have a relationship with acid and alkaline phosphatases, and succinate dehydrogenase activity. Dual plant inoculation with both endophytes increased the number of pods per plant, the weight of plant seeds, and fresh and dry weight of pod.

 


3/15 PHYTOPLANKTON SPECIES COMPOSITION OF THE IRRIGATION AND DRAINAGE CANALS IN ASWAN PROVINCE, SOUTH EGYPT

A.M. El-Otify

Department of Botany, Faculty of Science, Aswan 81528, Egypt

Phytoplankton species composition as well as their relative abundance and spatial distribution were investigated in shallow-running water habitats (irrigation and drainage canals) in Aswan Province. In this investigation, a total of 90 species representing 55 genera and five main algal groups namely; Cyanoprokaryota (10 species), Bacillariophyceae (38 species), Dinophyceae (two species), Euglenophyceae (five species) and chlorophyceae (35 species) were recorded from the irrigation and drainage canals. However, the euglenoid phytoplankton were recorded only in the drainage canals and were completely absent in the irrigation canals. The most common phytoplankton species were the pennate diatoms; Cocconeis placentula, Fragilaria ulna and Navicula cryptocephala as well as the centric diatom; Cyclotella meneghiniana. The major taxa (important species) were quantitatively estimated and   generally represented by 43 species. Six clusters were recognized after the application of cluster analysis by the application of TWINSPAN classification technique to the recorded species and the investigated sites. These clusters were named after the dominant species as: Navicula exigua, Planktothrix agardhii – Peridinium sp., Navicula radiosa – Lagerheimia ciliata, Crucigenia rectangularis, Gomphonema angustatum – Surirella ovata and Fragilaria ulna – Navicula cryptocephala – Navicula exigua – Nitzschia sp. The clusters that combine the sites of the irrigation canals were grouped together and those that corresponded to the sites of the drainage being in an other group. Detrended Correspondence Analysis (DCA) indicated such similarities and also reflected the similarity between the canals which located in close proximity to each other. The results provide evidence that the most important factors in characterising the phytoplankton clusters were the electrical conductivity, NO3-N, SO4,Ca2+, Mg2+ and the depth of water in the investigated canals.

 

4/15 MORE FERNS AND PALYNOFACIES FROM KURNUB SANDSTONE FORMATION IN NORTH JORDAN

M.H. Darwish and G.M.A.Lashin*

Botany Dep., Faculty of Girls, For Arts, Science and Education,

Ain Shams University.

*Botany Dept., Faculty of Sciences, Zagazig University, Egypt.

Impressions of fragments of vegetative organs of a few ferns are recorded from the Lower Cretaceous Sandstone beds in Kurnub Formation, North Jordan . Palynofacies of these plant bearing beds are of varying composition. The phytoclasts indicate freshwater influence and are represented by only a few particles of terrestrial organic matter and are barren of any datable palynomorphs. The facies demonstrate an increasing of non-marine influence which is in agreement with the lithological character of the succession. Comments on the composition of the flora are given.

 

5/15 SYNERGISTIC ANTIBACTERIAL ACTIVITY OF FUNCTIONAL MILK GLYCOPROTEINS (LACTOFERRIN) AGAINST ANTIBIOTIC-RESISTANT FOOD POISONING BACTERIA

M.K. Ibrahim and S.S. Ragab*

Microbiology Dept., Faculty of Science, Ain Shams University

*Food Science and Nutrition Dept., Faculty of Home Economics,

Minufiya Universty

       The antibacterial potency of each of three fractions of milk glycoproteins (apo-lactoferrin, holo-lactoferrin and lactoferrin hydrolysate) was studied individually and in combination with five antibiotics (tetracycline, cloramphenicol, gentamicin, ampicillin and vancomycin) against five antibiotic-resistant bacterial isolates associated with food-borne diseases and other human infections (Staphylococcus aureus, Bacillus cereus, Escherichia coli, Yersinia enterocolitica and Salmonella typhi). Data indicated that all the tested milk glycoprotein fractions had stronger antibacterial activities as compared with individual antibiotics used. Both apo-lactoferrin and holo-lactoferrin had a slightly higher antibacterial potency (mic was in the range of 0.30 - 0.45 μg/ml) than lactoferrin hydrolysate (MIC was in the range of 0.55 - 0.65 μg/ml), whereas the minimal inhibitory concentration of the tested antibiotics ranged from 0.55 to 0.90 μg/ml. Combination of a milk glycoprotein   (apo-lactoferrin or holo-lactoferrin) with the individual antibiotics was synergistic and resulted in a significant reduction in the MIC down to 0.20 to 0.35 μg/ml for either apo-lactoferrin or holo-lactoferrin and 0.40 to 0.55 μg/ml for lactoferrin hydrolysate. It was concluded that application of milk glycoproteins as natural food preservatives beside their other biological benefits for man could serve potentially in restricting thegrowth of antibiotic-resistant bacteria.

 

 

6/15 GENERATION OF BIOLUMINESCENT PSEUDOMONAS AERUGINOSA AND DETERMINATION OF BACTERIAL ADHESION TO CONTACT LENSES BY BIOLUMINESCENCE ASSAY

M.A.M. Yassien

Department of Microbiology, Faculty of Pharmacy,

King Abdulaziz University, Jeddah, Saudi Arabia

A positive glycocalyx producer Pseudomonas aeruginosa # 3 was transformed   with pUCGFP18 plasmid that was constructed by ligation of the shuttle vector pUCP18, SphI/SmaI treated, with GFP gene which was PCR amplified from pGLO plasmid. The expression of the GFP gene in the transformed strain (Pseudomonas aeruginosa # 3 strain GFP-18) did not affect on its glycocalyx production and adherence to the surfaces of contact lenses. The generated bioluminescent P. aeruginosa #3 strain GFP-18 was used for determination of the primary bacterial adhesion to the surface of contact lenses, depending on light emission measurement. The light produced by bioluminescent strains stably at 37 oC for more than 2 hours without significant change. The light emission measurements as a function of the number of adherent cells were studied. It was found that the light emission closely paralleled the number of CFU, giving a detectable signal from 3 X 102 cells. A comparative analysis of the relative degree of the primary adhesion of the constructed bioluminescent strains to different types of hydrogel contact lenses was performed with light emission measurement and a mild-sonication-cell culture recovery procedure. The data obtained by both techniques showed similar pattern of relative adhesion, however, the results of light emission measurement indicated greater density of cells ( 2.1-2.9 fold) on the surface of the lenses. The presented data showed that the constructed bioluminescent P. aeruginosa # 3 strain GFP18 can be used as a tool for applying a rapid, sensitive, less expensive and more convenient method (bioluminescent assay) for studying the primary bacterial adhesion to the surfaces of hydrogel contact lenses.

 

 

7/15 IMMUNE RESPONSE OF PERIPHERAL BLOOD MONONUCLEAR CELLS OF PATIENTS INFECTED WITH SCHISTOSOMA MANSONI AFTER IN VITRO STIMULATION WITH SMP40 ANTIGEN

M.F. Abouel-Nour, S.H. Hassan, M. Lotfy* and B.L. Doughty**

Zoology Department, Faculty of Science, Mansoura University, Mansoura, Egypt.

*Molecular Diagnostics Department, Genetic Engineering and Biotechnology Research Institute, Minufiya University, Sadat City, Minufiya, Egypt.

**Pathology Research, The University of Texas Medical Branch at Galveston (UTMB), Galveston, Texas 77555-0609, USA.

The pathogenesis of Schistosoma mansoni infection is largely determined by host T-cell mediated immune responses such as the granulomatous response to tissue deposited eggs and subsequent fibrosis. T-helper cells have been divided into Th1 and Th2 subsets on the basis of the cytokines secreted by Th clones. Th1 cells secrete primarily IFN-g, IL-2 and TNF-a, while Th2 cells secrete IL-4, IL-5, and IL-10. The various antigenic preparations of S. mansoni induce a different cytokines profile in vitro in human peripheral blood mononuclear cells (PBMCs) with different biological implications.A Schistosoma mansoni major egg antigen Smp40 was vector expressed and completely purified. In vitro stimulation of PBMCs from patients infected with S. mansoni with phytohemagglutinin (PHA) mitogen as a positive control, total soluble egg antigen (SEA) and purified Smp40 showed increased response of the Th1 cells to Smp40 as indicated from increasing of the cytokines they produce. On the other hand, the Th2 cells had decreased its secretion from IL-4, IL-5, and IL-13, in contrast to IL-10, it increased significantly. The overall pattern of cytokine profile obtained with Smp40 stimulation is reported to be associated with reduced collagen deposition, decreased fibrosis and granuloma formation inhibition. This may reflect its future prospect as a schistosomal vaccine.  

 

8/15 DECONTAMINATION OF DIFFERENT SPORE-FORMING
BACILLI BY ISOTHIOURONIUM DERIVATIVES

M.A. Abo-State and S.M. Ahmed*

National Center for Radiation Research and Technology (NCRRT), P.O Box 29, Nasr City, Cairo, Egypt.

* Egyptian Petroleum Research Institute (EPRI), Petrochemical Department,

Nasr City, Cairo, Egypt.

Non toxic, non corrosive surfactants, isothiouronium salts, were synthesized and used as decontaminating agents for five Bacillus strains (B.cereus NRRL-569; B.cereus ATCC 11778; B.cereus C1/1 B.sterothermophilus and B.circulans). Six derivatives tested against these Bacillus strains (dodecyl isothiouronium bromide I; hexadecyl isothiouronium bromide II; dodecyl isothiouronium iodide III; dodecyl isothiouronium dichloro bromo cuprate complex IV; stearyl isothiouronium bromide V and stearyl isothiouronium dichloro bromo cuprate complex VI). Four compounds gave postive results indicating large inhibition zone around the discs. These isothiouronium compounds (2mg/ml) reduced the viable count of the different Bacillus strains by about 2 to 6 log cycles (i.e. 99% to 99.9999%).When sodium perborate was (0.2 mg/ml) added to these compounds there were more decrease in the viability.

 

9/15 GENETIC IMPROVEMENT OFSTREPTOMYCES CLAVULIGERUS FOR CLAVULANIC ACID AND CEPHAMYCIN C ANTIBIOTIC PRODUCTION BY UVINDUCEDMUTANTS, USING A GENETIC CONSTRUCTED STRAIN AS TESTER.

K.M.A. Khalil

Genetics and CytologyDepartment, National Research Center, Cairo, Egypt.

Streptomyces clavuligerus is a gram-positive, filamentous bacterium that produces cephamycin C antibiotic and clavulanic acid, a potent inhibitor of β-lactamases. The combined use of clavulanic acid and broad-spectrum β-lactam antibiotics represented an important therapeutic strategy to combat the rapid increase in β-lactam resistance. A tester strain for clavulanic acid was constructed by transformed pBC1 plasmid to E. coli which, carried Ampicillin resistance (β-lactamase producer), and mini-Mu transposable insertion that can integrate into random sites of chromosome and induce insertion mutations. Transformants were tested electrophoretically on agarose gel and proved to have the plasmid.However, transformant JMBC was selected as a tester strain for clavulanic acid. Moreover, K7 was selected from B. subtilis as a testerstrain for cephamycin C production. Streptomyces clavuligerus was treated with UV using different times. Survival percentage of the original strain dropped from 100 % at zero time to 6.0, 0.03, 0.01, 0.0005 and 0.0004% after UV treatments for 1, 3, 5, 7 and 9 min, respectively. About190 isolates were isolated after UV treatments. However, 64 mutants were selected, i.e., 25 mutants after one min, 22 mutants after 3-min UV treatment. In addition, 17 mutants were isolated after 5, 7 and 9-min UV treatments. On the other hand, Str. clavuligerus was treated with UV on different doses and 60 mutants were selected and tested for their clavulanic acid production. Sixteen mutants (26.6%) were less activates than wild type. Moreover, 28.3% of the tested mutants showed the same wild type productivity. About 45% of tested mutants proved higher activities in clavulanic acid production than Str. clavuligerus. However, two mutants were selected after UV treatment, one after one-min and the second after 3-min, showed higher productivities than the wild type. Its clavulanic acid production was 125% compared with the wild type strain of Str. clavuligerus. Moreover, out of the mutants selected after UV treatments, 63 were tested for their activities to produce cephamycin C antibiotic. Twenty-three mutants (36.5%) were less producers, while 12 mutants (19%) showed the same wild type productivity. About 44.4%, (28) mutants, were higher producers than the wild type. Four mutants, one after one min and three after three min UV treatments were 120% as Str. clavuligerus. However, UV treatments showed different responses with different times, but for 1 and 3 min it was very important to induce and obtain higher producer mutants. Two mutants selected after UV treatment for 1 and 3 min, were the best clavulanic acid producers. Its production reached about 125% compared with the wild type. Moreover, four mutants, one after 1-min and three after 3-min of UV treatment, showed 120% antibiotic production compared with Str. clavuligerus.

10/15 PRODUCTION OF CARBOXYMETHYL CELLULASE BY FUSARIUM OXYSPORUM AND FUSARIUM NEOCERAS FROM GAMMA-PRETREATED LIGNOCELLULOSIC WASTES

M.A.M. Abo-State

Department of Microbiology, National Center for Radiation Research and Technology (NCRRT), Nasr City, Cairo, Egypt

The effect of UV-radiation on the viability, of two strains of Fusarium were examined. Seven minutes of UV-exposure reduced the viable count of F.neoceras by 2.35 log cycles and that of F.oxysporum by 4.6 log cycles in a linear manner. Thirty four UV-mutants were examined for their growth, extracellular protein, reducing sugars and CMCase production. The highest productivity had been recorded for F.neoceras mutants No (1) and (6) exposed to 1min UV-radiation. While the highest productivity of F.oxysporum was mutant No (4) exposed to 4 min.. Growth on wheat bran produced CMCase more than that grown on CMC except for F.neoceras wild type. Growth on agricultural wastes pretreated with 10, 30 and 50 Mega rad. of gamma radiation revealed that the best CMCase was found in case of 50 Mega rad. pretreated (cotton stalks, maize stalks and rice straw). Pretreated rice straw gave the best CMCase activity when compared with cotton stalks and maize stalks.

 

11/15 THE EFFECT OF AMPICILLIN AND KANAMYCIN RESISTANCE GENES ON HEAVY METAL RESISTANCE LEVELS IN E. COLI

K.M.A. Khalil

Genetics and CytologyDepartment, National Research Center, Cairo, Egypt.

As a trial to find the relation between antibiotic resistance gene(s) and heavy metals resistance levels, two plasmids were transformed to E. coli EJMS, pUC18, carrying ampicillin (Amp) resistance and pBC1 which coded for Amp and kanamycin (Kan)resistance. Plasmid isolation and agarose gel electrophoresis proved that transformants carried the transformed plasmids. However, two transformants were selected EPUC carried pUC18 and EBC1, which was transformed with pBC1 plasmid. E. coli EJMS, EPUC and EBC1 were tested for their antibiotics sensitivity using different concentration of Amp and Kan antibiotics. E. coli EJMS was sensitive to all concentration of both antibiotics. EPUC was resistant to all concentrations of Amp and sensitive to all concentrations of Kan, while EBC1 was resistant to all concentration of Amp and Kan antibiotics. E. coli EJMS and the two transformants, EPUC and EBC1, were tested for their heavy metal sensitivity. Six heavy metals were tested, i.e., Co++, Cu++, Fe++ Hg++, Cd++ and Zn++ with different concentrations. The three cultures showed nearly the same level of resistance with all concentrations of Cu++ and Fe++. On the other hand, EPUC and EBC1 transformants showed a high level of resistance than the EJMS parental strain with Hg++, Zn++, Cd++ and Co++ heavy metal. However EPUC showed slight increase in Hg++ and Zn++ resistance than EBC1, while EBC1 showed also slight increase in resistance with Cd++ and Co++. However, the two transformants, EPUC and EBC1 showed more than five-fold increase in the level of heavy metal resistance than the parental strain with Hg++, Cd++ and Zn++. Moreover, when Co++ was used, the two transformants showed about 2.5-3 time fold increasing in heavy metal resistance level in comparison with parental strain. The obtained results indicate that no big difference could be detected in heavy metal resistance level between EPUC and EBC1 transformants. Both transformants carried Amp resistance gene, which reflects that Amp resistance gene plays an important role for increasing the heavy metal resistance level of Hg2+, Zn2+, Co2+, and Cd2+. Moreover, the Amp resistance gene dose has no effect on heavy metals resistance levels.

12/15 THE TAXONOMIC SIGNIFICANCE OF SEED PROTEINS IN ZYGOPHYLLUM SPECIES (ZYGOPHYLLACEAE) IN EGYPT

A.A.F. Khafagi

Botany Department, Faculty of Science, Al-Azhar University (forGirls), Cairo.

Eight Egyptian species belonging to genus Zygophyllum were studied. The study included the electropho­retic pattern of seed protein and three isozymes (esterase, acid phosphatase and perixodase) as a tool in plant classification. The results showed that the strongest similarity was between Z. aegyptium and Z. geslinii (75.5 %) and also between Z. simplex and Z. berenicense (74.6%). The lowest similarity was between Z. dumosum and Z. aegyptium (36%). the genus Zygophyllum could be classified into three main groups. The first group: Z. simplex; the second: Z. album, Z. aegyptium and Z. gesilinii and the third group: Z. coccineum, Z. berenicense, Z. decumbens and Z. dumosum. The electrophoresis of three isozymes in the studied species of Zygophyllum showed that esterase and acid phosphatase could be considered as positive markers while, perixodase was detected as negative marker. It was found that the use of the electrophoretic pattern was able to distinguish between even the closely related species.

 

13/15 SEED COAT SURFACE IN THE GENUS ZYGOPHYLLUM L. (ZYGOPHYLLACEAE) AND ITS TAXONOMIC SIGNIFICANCE

A.H. Mohamed

Botany Department, Faculty of Science, Al–Azhar University, Cairo, Egypt.

Scanning electron microscope (SEM) investigation of seed coat surface showed that five types of surface sculpture were recorded: tuberculate (in Z. simplex); reticulate (in Z. album, Z. aegyptium, Z. coccineum and Z. berenicense); ocellate (only in Z.geslinii); smooth (in Z decumbens) and verrucate (in Z.dumosum). Anatomical studies show that the tuberculate type results from the swollen cells of the epidermis, the reticulate pattern from the enlargement of the epidermal cells, the verrucate type from the verruca of the epidermal cells and ocellate type from irregular or wavy walls of epidermis cells. SEM investigation and anatomical characters of the seed coat show apparent diversity among the examined species.

 

14/15 SAVING EGYPTIAN’S WILDLIFE: RENEWING DAMAGED SOIL OF THE ENDANGERED MANGROVES (AVICENNIA MARINA) GROWN AT NABQ PROTECTED AREA, SOUTHERN SINAI

A.A. Ali

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

Long-term application of this new technique could be provide a real information on the sustainability of agricultural systems. In this trial, the effect of ceramic dust applications (once a year) on improving quality of damaged soil supporting dead mangrove plants were studied. Field experiments were conducted at Nabq protected area, Southern Sinai under ceramic applications (from conc. 1% to 10%) over three years (2000-2002).Ten soil samples were collected two times after the first and third year of ceramic dust applications. The soil quality (SQ) that evaluated as a function of a minimum dataset (MDS) of analytical biological, chemical and physical properties of soil were measured on field moist and air-dried soils. Obtained results showed that the 6% concentration of ceramic dust is able to renew the damaged soil at this area. Key of the SQ properties measured as minimum data sets was, the active microbial biomass (Camb), total microbial biomass/ total organic carbon (Ctmb CORG-1), active microbial biomass/ total organic carbon (camb CORG-1), basal respiration (BR), specific maintenance respiration rate (qCO2) and turbidity ratio (TR) accounted to 69.8%, 92.9% of the variation in SQIA (all selected properties of soil quality) after one- and three-years of practices, respectively. Using camb, ctmb CORG-1 and TR, the model variable accounted to 67.8%, 93.7% of the variation of SQIA after one- and three-years of treatments, respectively. When using only a single predictor variable in the model, active microbial biomass C was found a sensitive indicator of the SQ and accounted to 55.8%, 94.4% of the variation in SQIA after one- and three-years of applications, respectively. This study concluded that the calculated soil quality index’s (SQI's) were able to detect effects of management practices on soil properties because the procedure is adaptable to integrate most SQ properties and applicable to diverse soil-crop management systems. Moreover, this trial proved that using ceramic dust as an industrial pollutant is a useful economical material.


 

15/15 BIOSYNTHESIS, PURIFICATION AND CHARACTERIZATION OF PECTINASE FROM ERWINIA CHRYSANTHEMI 415

S.M. El-Sabbagh, W.A. El-Shouny* and M.M. Aly**

Botany Department, Faculty of Science, Minufiya University, Egypt

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

**Biology Department, Faculty of Education, Kafr EL-Sheik,

Tanta University, Egypt.

       The phytopathogenic bacterium Erwinia chrysanthemi 415 produced high amount of pectinase in the minimal salt medium. The maximum level of extracellular pectinase activity was obtained under optimum growth conditions for 48 hr at 30ºC and pH 8.0. Pectin (2%) was the best carbon source, whereas potassium nitrate (2%) was the most suitable nitrogen source. The highest activity of pectinase (138 U/ml) was recorded in the modified medium. The enzyme was purified by precipitation at 75 % saturated (NH4)2SO4 and gel filtration to 7.82 folds. The enzyme had a molecular weight of 28 KDa as determined by SDS-PAGE. The pH and temperature optima were 8 and 30ºC. The enzyme exhibited thermal stability at 30 and 35ºC, while the activity was completely lost at 50ºC. Addition of sorbitol at 75 μg/ml increased the enzyme activity to 123.2%. Pectinase was stimulated by Ca2+ ion, whereas the other tested metal ions caused marked levels of inhibition. The optimum pectin concentration was 2%. Km value of the purified enzyme was calculated to be 3.1 μM. As the enzyme concentration increased , its activity was also increased up to 20μg/ml. The end products of pectin degredation revealed a spot corresponding to the mono-galacturonic acid markers as detected by paper chromatography. The purified pectinase caused electrolyte loss and rapid maceration of potato tissue with an increase of pH in the tissue homogenate which favoured the enzyme activation. The purified enzyme had no toxicity against the DNA of Escherichia coli.

16/15 DETECTION OF BEAN YELLOW MOSAIC VIRUS BY THE USE OF RT-PCR AND SOME PHYSIOLOGICAL ALTERATIONS ASSOCIATED WITH VIRUS INFECTION OF VICIA FABA. L.

F.A. Fattouh and A.M.A. Hassan

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

Vicia faba L. Nobareia-1 cultivar was surveyed for Bean Yellow Mosaic Virus (BYMV) diagnostic symptoms. There was a 46% reduction in the leaf area of infected leaves. Physiological alterations in infected leaves included a 35% reduction in the photosynthetic pigments (chlorophyll a and b). There was a 78% marked increase in total phenolic compounds. Free amino acids and soluble proteins were higher also in infected leaves. Total available carbohydrates was higher in BYMV infected leaves which could be attributed to inhibition of translocation of assimilates in virus-infected leaves. Comparison of the protein profile of infected and uninfected faba bean leaves allowed the detection of two proteins of molecular weights of about 70 and 48 KDa only in uninfected and not in BYMV infected leaves. A universal primer of the Potyviridae family was used for the detection of BYMV. One DNA band of molecular weight 1871 bp was detected by the use of the RT-PCR in BYMV- infected tissue.
 

 

17/15 VEGETATION OF THE NILE SYSTEM AROUND OLAMA ISLAND NEAR BENHA

M.N. Shehata and M.A. El-Galaly

Botany Department, Faculty of Science, Zagazig University, (Benha), Egypt.

Difference in species cover and composition of macrophytes are visualized by means of multivariate analysis of the Nile system at Olama island near Benha. The TWINSPAN classification revealed 8 vegetation types; 5 vegetation types are dominated by aquatic species while 3 vegetation types are dominated by weed species. Their dominant species are Eichhornia crassipes and Echinochloa stagnina (swamps), Vossia cuspidata (islet), Phragmites australis (river bank), Persicaria salicifolia and Cyperus rotundus (Syyalah), Urtica urens (first terrace) and Biden pilosa (second terrace). The suggested vegetation types are well segregated along the DCA axis one which reflects soil moisture, salinity (as indicated by EC values), fertility (as indicated by the organic matter and phosphorus) and species diversity gradients. It was found when soil moisture decrease, species diversity, salinity and fertility increase. This axis reflects also a gradient of human interference, starting with the vegetation of less disturbed habitats (swamps, islets & river bank), disturbed habitats (Syyalah and first terrace) and ending with fully man – made habitats (second terrace).    
 
18/15 PLANT FRAGMENTS FROM QUATERNARY TUFA DEPOSITS AT BIR DUNGUL, SOUTHWESTERN DESERT, EGYPT
M.H. Darwish

Botany Dep., Faculty of Girls, For Arts, Science and Education,

Ain Shams University.

Impressions of fragments of dicotyledon and monocotyledon leaves are described for the first time from Quaternary Tufa deposits of Bir Dungul, Egypt. This raises the number of fossil plant species known from the Quaternary of Egypt from 17 to 23. Comments on the Quaternary flora and climate are given.    

 

19/15 CHARACTERIZATION OF AN ACTIVE SUBSTANCE WITH PROMISING ANTIMICROBIAL ACTIVITY PRODUCED BY STREPTOMYCES FLAVEOLUS

G.M. Elsherbiny and B.M. Refaat

Botany and Microbiology Department, Faculty of Science, Al-Azhar University,

Madenit Nasr, Cairo, Egypt

An actinomycete culture was isolated from a soil sample collected from Al-Dakhaliah district, Egypt. The isolate No. 13 produced a wide spectrum active substance (anti-Gram positive, anti Gram negative bacteria and anti-unicellular and filamentous fungi). From the taxonomic features the isolate matches with Streptomyces flaveolus in the morphological, physiological and biochemical characters. Thus it was given the suggested name Streptomyces flaveolus -Dakh-13 . The isolate produced an active substance which was extracted by ethyl acetate. The separation of the active ingredient and its purification was performed using thin-layer chromatography. The physiochemical characteristics of the purified active substance including color, melting point, solubility, elemental analysis, spectroscopic characteristics and chemical reactions have been investigated. The biological activities of the purified active substance (MICs) were also determined.

20/15 INDUCTION OF MUTATION IN STREPTOMYCES VENEZUELAE V2 MUTANT FOR PROTEASE OVER-PRODUCTION, ISOLATION, PURIFICATION AND CHARACTERIZATION

K.M.A. Khalil and A.L. Kansoh*

Genetics and CytologyDept. and*Microbial Chemistry Dept.,

National Research Center, Dokki, Cairo, Egypt.

V2 mutant isolated from Streptomyces venezuelae DSM 40727 was treated with UV at time intervals as a second step selection for proteases over-production. Survival percentage(s)   of the V2 mutant dropped from 100 % at zero time to 10.0, 1.0, 0.31 and 0.23% after UV treatments for 1, 3, 5 and 7 min, respectively. A total of 246 selected mutants were obtained, including 48, 42, 85 and 71 mutants isolated after UV treatments for 1, 3, 5 and 7 min, respectively. All selected mutants were tested for their protease production. Only 40% of the obtained mutants were less producers while 30% of mutants were the same parental productivity and 27% of mutants were higher producers than V2 parental mutant. Three mutants isolated after UV treatments for 1, 3 and 5 min were the best producers mutants after 3 days of incubation, its production reached 130% as V2 parental mutant. One mutant only, isolated after UV treatment for 1-min, was the best producer after 5 days of incubation with the same productivity (130%). The chosen mutants were assayed quantitatively to test the protease activity. Of all these mutants a UV3-18 that had the highest potential for protease activity was chosen. Factors affecting protease production by UV3-18 and its wild type S. venezuelae were studied. Optimum production for protease enzyme on a rotary shaker (180 rpm) at 300C was achieved after five days incubation for UV3-18 mutantand initial pH value of 7.5. Partial purification of UV3-18protease enzyme in the culture supernatant was achieved at 60-90% acetone precipitation with a purification of 6.4 fold and 83.1% recovery. Further purification of UV3-18enzyme preparation was achieved on column chromatography Sephadex G-100 and DEAE cellulose with purification of 25.1 & 80.1 fold, and 63.8 % & 59.3 % recovery, respectively. The optimum temperature of the UV3-18 protease enzyme activity was 500C for 30 min. and pH value of 9.0. The enzyme proved to be stable up to 500C and in the pH range of 7.0 to 10.0. Some cations as K, Mg, Ca, Na, Fe, Mn and Cu activated the protease enzyme of UV3-18 by a range of 108.5 to 208.3 %. Addition ofsodium dodecylsulphate and other commercial detergents showed a slight decrease in activity by about 12.0 to 21.0 %.

 

21/15 BIOCONTROL OF LATE WILT DISEASE OF MAIZE CAUSED BY CEPHALOSPORIUM MAYDIS BY RHIZOSPHERE FUNGI

N.A. Abd-Allah

Microbiology Department, Faculty of Science,

University of Ain Shams, Cairo, Egypt

The present investigation aimed to study the role rhizosphere actinomycetes as a biocontrol agents of late wilt disease of maize cuased by Cephalosporium maydis. In this study, five actinomycete species were isolated from the rhizosphere of maize and were identified. They were found to have an inhibitory and antagonistic activity against the pathogen (Ceph. Maydis). They also have a promoting effect on the growth and development of maize when added singly and have a more promoting effect when added in combination. Streptomyces microflavus, produced five active components inhibiting the growth of the pathogen, St. purpureus and St. rochei produced four active components and the other two species Saccharomonospora viridis and St. flavus produced only three active components. The active component of Rf 0.75 was the most common and detected in the culture filtrates of four of the five tested species.

22/15 POLLEN MORPHOLOGY OF SOME TAXA OF ALSINOIDEAE (CARYOPHYLLACEAE) AND ITS TAXONOMIC VALUE

S.F. Khalifa, H.A. Hussein* and S.S. Teleb*

Botany Department, Faculty of Science, Ain Shams University

*Botany Department, Faculty of Science, Zagazig University

The pollen morphology of 29 taxa belonging to 13 genera, 24 species and 5 subspecies of the Caryophyllaceae-Alsinoideae, was investigated using the Light Microscope (LM) and the Scanning Electron Microscope (SEM). Pollen grains are either isopolar (11 taxa) or apolar (18 taxa). Isopolar grains are tricolpate whereas the apolar grains are polypantoporate with 8-27 pores. The placement of Minuartia geniculata within genus Minuartia was discussed depending on its pollen characters. The phylogenetic status, of the taxa investigated was discussed in the light of some of their pollen attributes viz., shape and number of apertures, tectum pattern and exine sculpture. Moreover, an artificial key based on the palynological characters was provided.

 

23/15 INTERACTION BETWEEN SALINITY AND GIBBERELLIN ON GROWTH, YIELD AND MINERAL COMPOSITION OF TRITICUM AESTIVUM L.

N. El-Sawaf

Botany Department, Faculty of Science, Cairo University.

A pot experiment was carried out at the greenhouse of the Faculty of Science, Cairo University, during two successive seasons, to study the morphological and yield characteristics as well as mineral composition of wheat plants (Triticum aestivum L. cultivar Sakha 69), grown under different levels of salinity and sprayed with gibberellin (GA3). Results revealed that all tested salinity levels reduced plant height, number of tillers, total number of leaves and fresh and dry weight per plant; a response that was furthered with increased salinity level. Meanwhile, foliar application of a relatively high concentration of GA3 (100 ppm) minimized the adverse effects of salinity on these growth parameters. On the other hand, all applied salinity levels decreased the yield characteristics including number of spikes per plant, mean length of spikes, fresh and dry straw weight per plant, fresh and dry grain weight per plant and 100-grain weight (grain index) of wheat. Still, the response was greater at the higher than lower levels of applied salinity. Meanwhile, GA3 alleviated such adverse effects of salinity; more prominently when applied at 100 ppm. Similarly, the percentage of phosphorus and potassium, in either leaves or grains, decreased whereas the sodium, calcium or chloride increased under the applied salinity levels. The foliar application of GA3 alleviated (phosphorus and potassium) or reversed (sodium, calcium or chloride) such effects especially at 100 ppm GA3.

24/15 factors affecting the activities of three plant growth promoting microbial species against two fungal pathogens

Z.K. Mohamed, M.A. El-Sibaie*, U.F. Ali** and A.M. Abdel-Gawad*

Botany Department, Faculty of Science, Cairo University,

*Desert Research Center, Ministry of Agriculture,

**Department of Biological Sciences, Faculty of Education, Ain Shams University.

The plant growth promoting and antagonistic activities of   Azotobacter chroococcum, Streptomyces sp and Chaetomium globosum against Fusarium oxysporum and Alternaria solani were studied as well as the effect of some nutritional factors. thus 49 Azotobacter spp., 20 Streptomyces spp. and 8 Chaetomium spp. were isolated from the rhizosphere of different plants from different localities in Egypt and screened for their antifungal potentiality and plant growth promoting activities. The results showed that 18 Azotobacter, 10 Streptomyces and 7 Chaetomium isolates exhibited antifungal activity against F. oxysporum and/or Alt. solani. Nearly all isolates showed pronounced growth promoting activity. A. chroococcum, Streptomyces sp and C. globosum were chosen for this study. The three tested bioagents were capable of utilizing different carbohydrates as a sole carbon source. Starch proved to be the best carbon source for the antifungal activity of either A. chroococcum or Streptomyces sp. against the two tested pathogens, while sucrose was the best for enhancing antifungal activity of C. globosum. Good levels of antifungal activity of the three bioagents were supported in the presence of ammonium and nitrate forms as nitrogen sources (KNO3, (NH4)2SO4, NH4Cl).The results also showed that A. chroococcum exhibited a pronounced antifungal activity against both pathogens over a narrow range of pH (6-8) and the highest activity was at pH 7.0, whereas the pH range of for antifungal activity of Streptomyces sp. was (6-8.5), while the pH range for C. globosum was (5.5-8.5). The present data showed that the antifungal activity of the three bioagents against the two pathogens was best at 30ºC.
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