Vol. 28, February, 2008.

acheter cialis usa 1/28 BIODEGRADATION OF P-CRESOL BY ASPERGILLUS FLAVUS

Amany S. Youssef

Botany Department, Microbiology Division, Faculty of Science,

Alexandria University, Egypt.

commander viagra rapidement Aspergillus flavus encoded by AF100 was obtained from Microbiology Laboratory, Faculty of Science, Alexandria University. The fungus was assayed for its ability to degrade p-cresol commonly found in agro-industrial wastes. The biodegradation assay was performed in liquid medium using p-cresol as a sole source of carbon. Optimization of cultural conditions (concentration of the different chemical constituents, pH and temperature) for p-cresol degradation by free and immobilized cells was also performed. The maximal rate of p-cresol utilization (100% after 9 hours) by contrefacon viagra danger Aspergillus flavus was achieved under shaken condition by free cells at the following concentrations: Na2HPO4 (4 g/l), KH2PO4 (3 g/l), FeCl3.6H2O (0.03 g/l), MgSO4.7H2O(0.4 g/l), (NH4)2SO4 (3 g/l), yeast extract (0.4 g/l), at pH 6 and 30°C. In conclusion, the present results indicate the potentiality of tribulus terrestris ou viagra Aspergillus flavus to enhance biotreatment of p-cresol pollution of industrial liquid wastes.

 

effet du cialis chez la femme  

viagra generiques 2/28 EFFECT OF utilisation du cialis 20mg PEG CONCENTRATIONS ON EMBRYO FORMATION AND PLANTLET GROWTH FOR SOME DATE PALM CVS IN VITRO.

combien coûte du viagra 1- LOWER PEG CONCENTRATIONS

W. H. Wanas*, S.F. El-Sharabasy** and A.Y. Al-Kerdany**

* Fac. of Agric., Ain Shams Univ. and ** CLDPRD. ARC.

This study was carried out at the tissue culture laboratory of the central laboratory of date palm research and development ,Agriculture research center, Ministry of agriculture ,Giza ,Egypt through the period from 2004-2006 to evaluate three date palms cultivars (Sewy, Zaghloul and Sakkoti) embryos and plantlets subjected to PEG concentrations (0.0, 0.4, 0.8, 1.2 and 2.4%) for six weeks.PEG levels at 2.4% included the lowest significant percentage of survived embryos for Zaghloul and Sakkoti cvs while it was 100% for Sewy under all PEG levels (0.0-2.4%) however, the plantlet growth in terms of shoot length achieved the highest length under higher PEG level 2.4% for Sewy and Sakkoti cvs with insignificant differences between them. Moreover, the number of roots increased with increasing PEG level for all the cultivars, however, Sewy cv.   was significantly the highest indicating higher tolerance for drought. The same trend was clear for root length as it increased by increasing PEG level for three cultivars and almost for Sewy cv.   at 1.2 and 2.4%.

 

qui à essaye le viagra 3/28 PURIFICATION AND PROPERTIES OF XYLANASE FROM IMMOBILIZED CELLS OF BACILLUS PUMILUS.

Amany S. Youssef

Department of Botany, Microbiology Division, Faculty of Science,

Alexandria University, Alexandria, Egypt.

Xylanase produced from immobilized cells of cialis fertilité Bacillus pumilus grown on shacked liquid medium was purified by ethanol fractioning, gel filtration and anion exchange chromatography. The pooled fractions of the major protein component yielded 12-fold purification of the crude enzyme preparation. The molecular weight of xylanase was calculated as 40 kDa by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The temperature and pH optima for its activity were 100ºC and 9, respectively. The enzyme retained its stability at 100ºC for 15 minutes. These thermophilic and alkalophilic properties indicate that the xylanase enzyme derived from Bacillus pumilus has the potential to be used for industrial applications.

 

 

4/28 EFFECT OF PEG CONCENTRATIONS ON EMBRYO FORMATION AND PLANTLET GROWTH FOR SOME DATE PALM CVS IN VITRO.

2-HIGHER PEG CONCENTRATIONS

W.H. Wanas*, S.F. El-Sharabasy** and A.Y. Al-Kerdany**

* Fac. of Agric., Ain Shams Univ., ** CLDPRD. ARC.

This study was carried out at the Central Laboratory of Date Palm Research and Development, Agriculture Research Center during 2005 to 2006 to evaluate three date palm cultivars (Sewy, Zaghloul and Sakkoti) embryos and plantlets subjected to PEG concentrations (0.0,3% ,4% and 5%) after 12 weeks on three subculture. In the three subsequent subcultures, the survived embryos percentage was higher for Sewy in the first and second subcultures at 3 and 5% PEG concentration but at the third subculture the three cultivars were equal at 5 % PEG . The plantlets survived under all PEG concentrations without any decrement in survival percentage in case of Sewy and Sakkoti cvs compared to significant decrease in case of Zaghloul cv. Regarding the shoot length, Sewy cv represented the first in order under 5% PEG but the differences were insignificant between Sewy and Sakkoti then Zaghloul cvs in the first and second subcultures. In the third subculture, the highest shoot length in Sewy and Zaghloul cvs was at the control and the differences among the three cvs were insignificant. The same trend was obvious for the number and length of roots and the survival percentage of the plantlets during the three subcultures. The lowest survival percentage was recorded for Zaghloul cv then Sakkoti and Sewy cvs.

 

5/28 MATHEMATICAL MODELS APPLICATION TO OPTIMIZE PHYCOCYANIN PRODUCTION IN SPIRULINA PLATENSIS.

Eman M. Fakhry and Dahlia M. El Maghraby

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

The cyanobacterium Spirulina platensis is one of the most promising sources of the natural colourant phycocyanin pigment. Phycocyanin production was enhanced under laboratory conditions through developmental factors. Initial screening of the medium constituents was performed using statistical designs to discover which nutrient component (s) affecting phycocyanin production. Among these constituents, trace 2 was found to be the only significant factor. This finding directs our attention to study the optimization experiment to determine the optimum concentration level of phycocyanin. It was shown that the phycocyanin content increased from 17.80 μg/l (measured in control medium) to 24.66 μg/l (measured in optimized medium) with 1.6 fold trace 2 concentrations. That is, to reach the maximum phycocyanin production with respect to medium constituents, only trace 2 concentration in the medium have to be increased.

 


6/28 AUTECOLOGICAL STUDY ON CAREX EXTENSA GOOD.

Mohamed E. Abu Ziada

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

       This study deals with the ecological characteristics, temporal nutrient accumulation in different plant parts of Carex extensa and periodical changes in biomass and assimilating surface area. Meanwhile, the effect of utilization of sewage sludge, town refuses and cattle manure on growth and heavy metals accumulation by Carex plant as well as the effects of crude oil and salinity were investigated. This tufted sedge prevailing the silted borders of salt marshes in the Deltaic Mediterranean coastal region, at New Damietta city. The soil is sandy textured with predominant of fine sand (91.35%), highly saline (T.S.S.=1.28%) and slightly alkaline (pH=7.66). Mixing organic wastes with sandy soil increased the organic carbon and total nitrogen content and decreased the soil reaction. Sewage sludge and municipal wastes treatments, especially low levels, had pronounced effects on plant height, number of leaves and dry matter production, while the cattle manure resulted in comparatively lesser effect in this concern. The heavy metals concentrations (Fe, Zn, Cu, Pb and Co) in Carex shoot was progressively increased by increasing the rate of the different organic wastes. Crude oil appeared to inhibit the root elongation and adversely affected the plant growth. Excess salinity was found to reduce leaf growth that, in turn, directly contributes to the reduction in vegetative yield.

 

7/28 ACTIVITIES OF ANTIOXIDANT ENZYMES AND ACCUMULATION OF Α-TOCOPHEROL IN MEDICAGO SATIVA SEEDLINGS SUBJECTED TO DARK AND CHILLING CONDITIONS

Mohamed M. Ibrahim* and Sameera O. Bafel**

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

** Botany Department, Faculty of Science, King Abdel-Aziz University, Jeddah, Saudi Arabia.

Chilling-associated oxidative damage that enhanced the production of active oxygen species (AOS), slow down metabolism and modify membranes resulting in lipid peroxidation. A marked increase in the level of H2O2 was estimated in alfalfa leaves after dark chilling treatment, and as a consequence, oxidation damage due to H2O2 accumulation could cause lipid peroxidation of membrane and result in a significant increase in malondialdehyde (MDA) content. After recovery period the MDA content decreased significantly due to the increase of phenolic compounds which suppress lipid peroxidation. Also, the redox properties of α-tocopherol play an important role in adsorbing and neutralizing free radicals, and provide some forms of antioxidant protection. Activity of superoxide dismutase (SOD; 1.15.1.1) increased straight away the dark chilling stress, whereas catalase (CAT; 1.11.1.6), ascorbate peroxidase (APX; 1.11.1.11) and glutathione reductase (GR; 1.6.4.2) activities were slightly increased after chilling treatment. During the recovery period activities of CAT, APX and GR increased significantly which restrict the recycling of active oxygen species associated with chilling stress. The results indicated that cold treatment may have initially caused injury, thereafter during the recovery period leaves co-ordinated and enhanced the capacity of the antioxidative system, thus diminishing the potential for active oxygen species.

 

8/28 ROLE OF MICROFLORA IN CARBOHYDRATE DEGRADATIONS AND FERMENTATION PRODUCTS OF STORED BAGASSE

Ahmed E.M.Noor El-Deen, Maghraby A. Selim*, Salem E. Zayed*

and Abd El-Paset A. Adam**

Faculty of Science, Botany Department, South Valley University Qena

* Faculty of Science, Chemistry Department, South Valley University, Qena

** Nag Hamady for Wood Production & Fabrication Company (NFB), Quality Manger, Egypt

       Eight samples of WBS were collected from wet bulk storage bagasse stack, each period ranged from 30 to 35 days. The bagasse samples were subject to acid hydrolysis to assay monosaccharide levels by microanalysis using HPLC standard methods. Fermentation byproducts resulting by microflora growth during storage were estimated by HPLC too. Glucose, xylose, arabinose, galactose, glycerol, and lactic acid were detected. Glucose was the major representative the cellulose fraction, which slightly influenced by the action of micro flora, that were isolated and identified on pervious studies. Xylose and arabinose represented the monomers of hemicellulose, which were strongly affected by action of microflora. Glycerol and lactic acid are byproducts of bagasse fermentation.

 

9/28 AUTOTOXICITY OF CHARD AND ITS ALLELOPATHIC POTENTIALITY ON GERMINATION AND SOME METABOLIC ACTIVITIES ASSOCIATED WITH GROWTH OF WHEAT SEEDLINGS.

Momtaz M. Hegab; Salah El-Den A. Khodary; Ola Hammouda; Hamada R. Ghareib

Departement of Botany, Faculty of Science, Beni-Sueif University, Salah Salm Street,

Beni-Sueif, Egypt.

In this study, the allelopathic effect of aqueous whole mature chard plant extract (Beta vulgaris L. var. Cicla) on wheat (Triticum vulgare L. var. Sides 1) and an associated weed (chard) was investigated.Plants used were sampled in 2006, then plant extracts were obtained after they were ground and processed with distilled water. Twenty five of wheat grains and the same number of chard seeds of uniform size and weight were placed in a mixture on sterile filter paper in 15cm Petri-dishes. Treated Petri-dishes were each supplied with 20 ml extract of 0.25,1, 4, 8, and 12% (w/v) while untreated control was supplied with 20 ml of distilled water. After 10 days the germination percentage, vigour value, seedling growth criteria and some physiological processes were counted. The aqueous extract retarded the germination of chard more effectively than that of wheat and the effect was concentration dependent. The lowest concentration stimulated the germination of both wheat and chard; on the other hand, the germination was retarded under the application of concentrations above 1%. However, 1% concentration had a positive effect on wheat and negative on chard. In HPLC analyses of the water-soluble extract of whole chard plant residue revealed the presence of eight phenolic aglycones that show the abundant of shikimic acid, (+) camphor, hydroxybenzoic, p- coumaric and vanillic acids and in trace amounts coumarin and protocatechuic acids. It was concluded that this extract may be used as a bioherbicide to control the germination and growth of itself (autotoxicity).

 


10/28 ALLEVIATION OF HEAVY METAL TOXICITY ON LUPINUS TERMIS PLANT BY KINETIN, BENTONITE AND ASCORBIC ACID

Samia E. Saffan

Botany Department, Faculty of Science, Zagazig University

Abolishing heavy metal cd+2 and pb+2 toxicity by addition of kinetin bentonite and ascorbic acid on some physiological processes of lupinus termis plant growing in the different concentrations of cd+2 and pb+2 (at 10 and 50 mg/L) were studied. A more pronounced decrease in chl.a / chl.b and carotenoids at different concentrations of heavy metal. Moreover, total soluble carbohydrates, protein contents showed a decline under both levels of cd+2 and pb+2. Proline content was higher in metal-treated plants than in untreated controls but total free amine acid of treated plants decreased. On the other hand, analysis of fatty acids composition showed a special decrease in unsaturated than saturated fatty acid under different concentrations of cd+2 and pb+2. The results of this study indicate that kinetin > bentonite > ascorbic acid can alleviate the harmfull effects of cd and pb on the metabolic processes of lupinus termis after 4 weeks old.

 

11/28 PRODUCTION OF PECTINASE (S) BY BACILLUS FIRMUS BOW33 ALLOWED TO GROW ON ORANGE-JUICES WASTES UNDER SUBMERGED FERMENTATION.

Sherif M. Husseiny, *Mamdouh S. El-Gamal, **Ali I.S. Ahmed

and **Hamead M.H. Khashaba

Botany Department, Women's College, Ain Shams University.

*Botany & Microbiology Department, Faculty of Sciences, Al -Azhar University.

**Biochemistry, Special Food & Nutr. FTRI ARC.

Studies were carried out on the production of pectinase (s) using orange wastes as a natural nutritional substrate for growing of Bacillus firmus BOW 33 under submerged fermentation (SmF) conditions. Higher titres of pectinase (s) were obtained at optimal conditions including incubation temperature, 37ºC; inoculum size, 6 ml from a heavy bacterial suspension, each ml contained 75 X1020 colony forming unit (CFU); the incubation period, 30 h; KH2PO4 as the best mineral salt; urea as best nitrogenous source; an optimum pH of 7 and liquid volume 25 ml in 250 ml-Erlenmeyer flask under static conditions.

 

12/28 STATISTICAL OPTIMIZATION AND PARTIAL CHARACTERIZATION OF AMYLASES PRODUCED BY HALOTOLERANT PENICILLIUM SP.

Mona Kh. Gouda and Yasser A. Elbahloul

Department of Botany, Faculty of Science, Alexandria University,

The production of extracellular amylase by the halotolerant fungus Penicillium sp. was statistically optimized in a submerged cultivation. Maximum enzyme production was obtained after two days of incubation in a medium containing 10% (w/v) NaCl, in addition to MgSO4.7H2O 1% and 1% (w/v) of starch. The optimum pH for growth and enzyme production was 4. Partial characterization of the crude enzyme revealed the presence of two enzymes with pH-optima at 9 and 11. Further more, the optimum temperature was 30°C at pH 11 and from 30°C to 90°C at pH value of 9. The two enzymes were stable in wide pH range with the maximum stability at pH 9 to 11 after 5 days and at temperature range of 40-60°C. Different starchy materials (barley grains, wheat grains, wheat bran, crushed wheat grains, birds feed grains, maize meal and wheat meal) were tested as substrates for amylase production in solid state fermentation (SSF). The highest enzyme production was obtained in presence of maize meal after 6 days of incubation at 30°C when enzyme assayed at pH 11.

 

13/28 EXO-POLYSACCHARIDE PRODUCTION BY NON- PIGMENTED STRAIN OF AUREOBASIDIUM PULLULANS AT DIFFERENT INITIAL SUCROSE CONCENTRATION AND ITS EVALUATION AS A FLOCCULATING AGENT

Ola. A. Abd El-Rahman, Fatma H.A. Mohammad, Fatma S.S. Ahmed

and Joseph Y. Farah

Microbiology and Immunology Department, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.

*Chemical Engineering and Pilot Plant Department, National Research Center

the influence of sucrose concentration on exo-polysaccharide, pullulan, production by Aureobasidium pullulans, NRRL 2311-1 was examined to optimize the quality and the quantity of the exo-polysaccharide produced. The exo-polysaccharide elaborated on shake flasks and on   fermentors were recorded over a period of 9 days. The level of exo-polysaccharide increased as the sucrose concentration was increased till 10% concentration. The exo-polysaccharide production was inhibited when 15% sucrose concentration was used. The influence of light on 5-L fermentor was also studied. The relationship between the presence of light and the production of exo-polysaccharide revealed the requirement of light for biomass and polysaccharide formation. Exo-polysaccharide production increased ~ one fold when the culture was incubated in light. Three different grades of exo-polysaccharide based on down stream processing were tested and evaluated as a flocculating agent. It was found that the first grade (Product I), which is the broth with the whole fermentation culture including the cells of A. pullulans, failed as being a flocculating agent. The settling time was reduced by using the polysaccharide concentration of the second grade (product II), which is the supernatant obtained after cell removal. Product III, i.e. the dried polysaccharide which was obtained after centrifugation, precipitation and drying, gave the same result as product II but it is more expensive. The initial sucrose concentration on the fermentation medium has negligible effect on the flocculating property of the exo-polysaccharide produced. Preliminary cost estimation for the process was carried out for free cells non extracted product (product II).

 

14/28 INTERACTIONS BETWEEN CADMIUM AND ZINC IN PHASEOLUS VULGARIS L. SP.NIBRASKA

Lamis D. Shabaan

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

The potential mechanis by which Zn antagonizes Cd toxicity was investigated in (Plaseolus vulgarisl. sp. nibraska), treated with 25µM Cd alone or 25µM Cd suplemented with Zn (10, 25, 50, 100 and 150µM) or treated with Zn alone (10, 25, 50, 100 and 150µM) were also given for comparison. Cd-induced strong oxidative stress as indicated by high levels of lipid peroxidation and inhibition of biosynthesis of pigments (chl-a, chl-b and total carotenoids). Zn supplementation reduced efficiently this oxidative stress as observed by the variation of these parameters. Zn-alone treated plants, however, did not show any variation in the above parameters. The activity of antioxidant enzymes [superoxidase dismutase (SOD) catalase (CAT) and ascorbate peroxidase (APX)], showed a very high increase in activity in Cd + Zn-treated plants as compared to Cd or Zn-alone. Zn antagonizes Cd-induced free radicals and oxidative stress. This results suggest that Zn supplementation proved to be inhibitory for Cd-induced oxidatixe stress and beneficial for the plant's survival.

 

15/28 PURIFICATION AND CHARACTERIZATION OF A THERMOSTABLE a-AMYLASE FROM PENICILLIUM BREVICOMPACTUM

Ashraf A. El-Bessoumy and Ebaa E. El-Sharouny*

Biochemistry Department and *Botany Department, Faculty of Science, Alexandria University, Alexandria, Egypt.

α-Amylase (EC 3.2.1.1) was isolated from the culture filtrate of Penicillium brevicompactum grown on a solid state fermentation medium containing banana skin as a waste substrate. The α-amylase was purified by 70 % ammonium sulfate fractionation, CM Sephadex C50 cation exchange column followed by Sepharose CL-6B gel filtration column. The overall purification was about 300.29 fold with a yield of 62 %. On using SDS-PAGE the final fraction showed only one protein band with a molecular weight of 90,000 Dalton. Lineweaver Burk plot revealed that the Km and Vmax of the enzyme were 0.045 g/ml and 25 U/ml respectively. The purified enzyme remained stable in a range of temperature up to 70°C and pH between 5-8. The optimum enzyme activity was displayed at 65°C and pH 6. Ca and Mg ions greatly enhanced the enzyme activity while other metal ions inhibited it. The enzyme was very rich in glycine, acidic and hydroxyl amino acids.

 

16/28 PROTOPLAST ISOLATION AND FUSION FROM CHLORELLA SP. AND CHLOROCOCCUM SP.

Atef M. Abo-Shady

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

The protoplast of Chlorella sp. and Chlorococcum sp. (isolated from fresh water of El-Kassed cannel at Tanta City) were isolated. Protoplast fusion between them was obtained by treatment with polyethylene glycol (PEG 6000 MW) and Ca2+ as CaCl2. Reproducibly high yields of protoplasts were obtained within the first few hours of treatment with a polysaccharide degrading enzyme (Cellulose onozuka R10). The protoplasts of both strains were able to regenerate cell walls and form cells when were resuspended in regeneration medium, which contained polyethylene glycol (PEG 1500 MW). The Uvitex 2B stain was used to detect the presence and regeneration of the cell walls. Auxotroph pigment mutants were isolated after UV-irradiation of both green wild type cells. These mutants differed in the growth requirement and light sensitivity between each other from their wild-type cells. The protoplast fusion was obtained from different mutants of both strains, when polyethylene glycol and Ca+2 were used. Green hybrid cells were obtained using selective conditions.    

17/28 PRODUCTION AND PURIFICATION OF CHITINASE FROM BACILLUS MC-1 GROWN ON SHRIMP SHELL CHITIN WASTES

Ashraf A. Elbessoumy, Mona E. Mabrouk*, Khalid Bassiouny**

and Nihal M. Elguindy***

FROM

*Botany Department, Faculty of Science, Damanhour Branch, Alexandria University, Egypt

**Genetic Engineering and Biotechnology Research Institute, Menuofiya University, Egypt.

*** Biochemistry Department, Faculty of Science, Alexandria University, Egypt.

Fourteen bacterial colonies locally isolated from chitin-rich soil showed different degrees of chitinolytic activities on agar plates amended with colloidal chitin. The most potent isolate of 6.7 activity ratio was selected for this study. Based on some phenotypic characteristic, it was identified as a member of as a member of Bacillus cereus- thuringiensis group and designated as B.MC-1. The bacterium grew well on shrimp-shell powder (SSP) as sole carbon and nitrogen source producing chitinase (0.2 U/ml) after 3 days incubation at 35°C. Bacillus MC-1 chitinase was purified by ammonium sulfate precipitation, followed by sequential chromatography on DEAE-Sephadex A-50, and Sephacryl S-200 HR. The MC-1 chitinase was purified 93.38 fold to homogenity with a final recovery of 58.68 % and a specificity of 1.4 U/mg protein. The purified enzyme showed optimal pH and temperature at 5.5 and 50 °C, respectively. The enzyme activity was stable within pH 4–7. It was stable up to 70 °C at pH 5.5. The purified chitinase appeared as a single protein band on SDS-PAGE with a molecular weight of approximately 66.6 kDa. Apparent Km and Vmax values of the chitinase for colloidal chitin were 0.05 mg/ml and 2 U/ml, respectively. Chitinase activity was stimulated by Ca2+, Mg2+ and K+.

18/28 EFFECT OF TWO FUNGAL EXTRACT ON CONSUMPTION AND SURVIVAL OF PSAMMOTERMES HYBOSTOMA (DESNEUX) (ISOPTERA: RHINOTERMITIDAE) IN ASWAN, EGYPT.

Soaad A. El-Zayat; Hoda M. Abdel-Wahab* and Mohamed S. Massoud

Botany Department, Faculty of Science, South Valley University, Aswan

* Zoology Department, Faculty of Science, South Valley University, Aswan .

Survival and wood consumption by workers of the subterranean termite Psammotermes hybostoma were assessed for 3 weeks on blocks of two timbers: Pleiognium solandarxi and Eucalyptus rostrata. These two timbers were tested with 3 concentrations (1 × 106, 3 × 106, 5 × 106) of aqueous extract of the two fungi: Cunninghamella echinulata and Chaetomium globosum (proved high cellulolytic activity in previous study). The fungus C. echinulata showed bad effect on termite feeding and survival on blocks of P. solandari timber treatment at all concentrations, while the same fungus improved termite feeding and survival on blocks of E. rostrata timber. The feeding of termites on both two timbers blocks treated with Ch. globosum extract showed strong decreasing with increasing the fungal extract concentraction. Data record improving in termite survival on E. rostrata timber with increasing the fungal extract concentraction. Ch. globosum was the best fungus in decreasing termite feeding on two timber blocks at all concentration, specially at 5 ×106 conc.

 

19/28 ITURIN ANTIBIOTIC FROM BACILLUS LICHENIFORMIS VARIANT

Fathy M.E. Serry, Holy N. Rabetafika* and Michel Paquot*

Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt.

*Gembloux Agricultural University, Industrial Biological Chemistry Unit 2, Passage des Déportés 5030 Gembloux, Belgium

A Bacillus isolate with potent antifungal activity was obtained during routine screening test. The isolate demonstrated activity against many fungi including, Aspergillus sp., Penicillium sp., Fusarium sp., Saccharomyces cerevisiae, and the dermatophytes: Trichophyton sp., Epidermophyton sp., and Microsporum sp. The isolate was tentatively identified as a variant of Bacillus licheniformis. The active component was identified as a lipopeptide antibiotic iturin A by RP-HPLC, MALDI-TOF, and TLC analysis. The study revives the interest in these compounds as potential antifungal agents in treatment of superficial mycoses.

 

20/28 SUSCEPTIBILITY OF AN EXTREMELY HALOPHILIC ARCHAEON, HALOBACTERIUM SALINARUM SHR TO HEAVY METALS

Hoda H. Yusef

Botany Department, Faculty of Science, Alexandria, Egypt

An extremely halophilic archaeon, isolated from a solar saltern in Egypt, Halobacterium salinarum SHR was tested for susceptibility to cobalt, cadmium, mercury, nickel and zinc ions in tryptone-yeast extract medium. The highest susceptibility was noticed with mercury and the bacterium showed a minimum inhibitory concentration (MIC) of the tested metals ranging from 0.07- 8 mM. A surprising high cadmium-resistance potential was recorded (8 mM) and the tolerance to Cd2+ increased with the increase of medium salinity. The effect of metal interactions between various concentrations of Cd2+ and 0.3 mM of other tested metals ( Co2+, Cu2+, Mn2+, Ni2+ and Zn2+) on the bacterial growth proved that only at 0.5 and 1 mM Cd2+ concentrations, the presence of Mn2+ and Zn2+ enhanced the bacterial growth.

 

21/28 DETECTION OF ANTIBIOTIC RESIDUES IN MILK AND IN SOME MILK PRODUCTS

Mohamed M. Omar, Mohamed M. El-Abbassy, Mostafa M. Ashour

and El-Sayed Abd El-Sattar

Food Science Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt

Raw milk samples were collected from local farms and markets located in Sharkia Governorate and these samples were subjected to Delvo test-SP to detect antibiotic residues. These samples were thirty of raw cow’s milk and thirty samples of raw buffaloe’s milk. The thirty samples of raw cow’s milk had five positive samples to Delvo test (16.66%) meanwhile out of the thirty samples of raw buffaloe’s milk only three samples were positive to Delvo test-SP (10%). The Yoghurt Culture test (YC test) was carried on the raw cow’s and buffaloe’s milk samples. The YC test gave positive results with six samples (20%) and three samples (10%) for the cow’s and buffaloe’s raw milk samples respectively. The sensitivity of YC test to some antibiotics and the time of minimum coagulum formation were determined, The penicillin spiked milk formed a curd after 2.5h at 0.06 IU / ml and after 4.00 h at 0.1 IU / ml , Ampicillin spiked milk, formed a curd after 2.5 h at 0.1μg / ml and after 4.00 h at 0.2 μg / ml, Gentamycin spiked milk a curd formed after 2.5 h at 4.00 μg / ml and after 4.00 h at 10.00 μg / ml and in the case of Streptomycin the curd was formed after 2.5 h at 10.00 μg / ml and after 4.00 h at 15.00 μg / ml. Also, Delvo test-SP was used on UHT milk and (Nido) instant full cream milk powder samples also. The results indicated that the UHT milk samples were free from antibiotic residues and the instant full cream milk powder samples showed one positive sample from fifteen examined samples (6.77%).

 

22/28 EFFICIENCY OF DISRUPTION OF PICHIA PASTORIS CELLS BY MECHANICAL METHODS FOR EXTRACTION OF WHOLE CELL PROTEINS

Abd El-Naser A. El Moghazy

Department of Microbiology and Immunology, Faculty of Pharmacy,

Al-Azhar University and Biotechnology Center, EIPICO.

The use of the methylotrophic yeast, Pichia pastoris, as a cellular host for the expression of recombinant proteins has become popular in recent years. Pichia is easier to genetically manipulate and culture and can grown to high cell densities. Cell disruption plays a key role in the isolation and release intracellular products of Pichia cell. In this study, Pichia pastoris had been tested to show the percentage of soluble protein release form cells and efficiency of disruption of cells by mechanical methods. High efficiency disruption of yeast was accomplished by using glass beads with size 0.5mm using vortexing for 30 min. When the cells were disrupted by vortexing with glass beads, the major factor that influenced the yield of protein was the ratio of glass beads/cell suspension volume. A grater rate of disruption was obtained when the ratio of of cell: beads: buffer was 1:2:2. For optimal cell disruption the optical density of cells should be less than 10. The shape and size of the tube in which the suspension was vortexed also affected protein recovery. The round-bottom glass centrifuge tubes gave the best results.It is recommended that beads and yeast suspension be chilled prior to disruption in order to offset any temperature rise during disruption and to prevent denaturation of protein. The efficiency of disruption of cells by homogenization was higher (90%) comperaring to (82%) obtained by vortexing.

 

23/28 PSYCHROBACTER SP. HY, A HALOTOLERANT PSYCHROTOLERANT BACTERIUM MANIFESTING CHROMATE REDUCTION POTENTIAL

HodaH.Yusef

MicrobiologySection, BotanyDepartment, FacultyofScience,
UniversityofAlexandria, Egypt

A psychrotolerant halotolerant bacterial isolate was recovered from seawater on tryptone yeast extract medium at 10°C. Cells were short rods to coccoid, non motile, non pigmented, non-sporing of 0.6 – 0.8 x 1.5 – 2 μm in size. Cells were oxidase and catalase positive. Growth occurred at 4 °C but optimal at 20°C and no growth was detected at 37 °C. The bacterium grew over a wide range of pHs (5.5 – 9.5) with maximal growth at pH 7-8. Grew optimally in presence of 0.5 M NaCl and tolerated up to 2 M salt. Phylogenetic analysis revealed 99.6% similarity to Psychrobacter glacincola. Therefore, the strain under investigation was designated Psychrobacter sp. HY. It showed good Cr(VI) reduction ability in minimal salts medium amended with 40 or 60 mg/l. Within 96 hours at 20 °C, the isolate showed 91.5 and 78% reduction of 60 mg/l CrO4-2 or Cr2O7-2, respectively. However, it displayed complete reduction of 40 mg/l CrO4-2 .Toxicity to chromate was observed at 100 mg/l of CrO4-2.

 

24/28 BIOREMEDIATION OF INDUSTRIAL WASTEWATER

I- ISOLATION AND CHARACTERIZATION OF COPPER PCOR RESISTANT GENE IN GRAM-NEGATIVE BACTERIA.

Khalid S. Abdallah*, Zakia A. Abo El-Kheir**, Om-mohamed A. Khafagi**, Hesham I. El-Kassas*** and Abla I. Alawady*

* Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center

** Botany Department, Faculty of Science (Girls), Al-Azhar University.

*** Institute of Environmental Studies and Research, Ain Shams University.

A HEAVY metal resistant Gram negative Enterobacter aerogenes bacterium was isolated from industrial wastewater pond at Sadat City, Egypt. Enterobacter aerogenes showed the highest level of copper biosorption compared with Proteus species. Based on the published sequence of the PcoR. Gene was detected in the isolated strain. Using PcoR primers, DNA fragment was amplified from Enterobacter aerogenes; the amplified fragment was cloned and sequenced. The revealed sequence data indicated that there is 98% similarity ratio between PcoR obtained from E. aerogenes clone and Cu gene of E. coli plasmid PRJ1004 DNA.

 

25/28 TAXONOMIC SIGNIFICANCE OF SEED MORPHOLOGY AND ANATOMY IN FOUR SENNA SPECIES (FABACEAE-CAESALPINIOIDEAE) IN EGYPT

Mona Adel Shiha

Biological Science and Geology Department, Faculty of Education,

Alexandria University, Alexandria, Egypt.

Seed external morphology and coat anatomy of four Senna species; Senna alexandrina Mill., S.didymbotrya (Fresen.) Irwina & Barneby, S. italica Mill. and S. occidentalis (L.) Link. in Egypt have been studied by both Light Microscopy (LM) and Scanning Electron Microscopy (SEM), in order to reveal the taxonomic relationships among them. Seed coat macromorphology characters studied include variations in dimension, shape, testa color. Variation was also found in the pleurogram from the point of view of its shape, position and texture. Seed coat micromorphological features revealed a remarkable topographic diversity of these apparently simple structures. The epidermal overall surface pattern and the anticlinal cell wall boundaries are striking features of seed coat surfaces. S. didymbotrya could be distinguished by its rugate surface pattern, S. alexandrina and S. occidentalis could be distinguished by their sinuate (zigzag) and beaded anticlinal cell boundaries. Anatomically, the testa has been found to be of great value in determining taxonomic relationships, S. occidentalis could be delimited by the presence of two malpighian layers, while one malpigian layer in the rest studied species. Phylogenetically, accordingly to the endosperm thickness, S. alexandrina is assumed to be the most advanced, and S. occidentalis is considered to be the less advanced within the studied taxa. Seed coat macro- and micromorphological features and seed anatomy characters could be provide useful additional characters in delimitation of the studied Senna species.

 

26/28 METABOLIC CHANGES IN SPINACIEA OLERACEAE L. PLANT GROWN IN SOIL AMENDED WITH SEWAGE SLUDGE

I. LIPID METABOLISM

Hegazy S. Hegazy and Lamis D. Shaaban

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

Leaves of spinach (Spinaciea oleraceae L.) plants cultivated in soil amended with sewage sludge (6%) showed sharp increase in all classes of neutral and polar lipids in comparison with plants grown in soil without fertilization and as well as with soil fertilized with ammonium nitrate (50kg. fd-1). While the analysis of chlorophyll ratios (chll.a and chll.b) showed no toxic effect at this rate of sewage sludge. We concluded that the application of sewage sludge at low rate enrichsoil nutrition.

 

 

27/28 MICROBIOLOGICAL AND MOLECULAR CHARACTERIZATION OF THE POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) AND ALKYLATED DERIVATIVES DEGRADING-BACTERIA ISOLATED FROM AN OXIDATION POND.

Laila E. Mekki, Ahmed Dewedar, Mohamed Tawfic* and Amer Diab

Botany Department, Faculty of Science, Seuz Canal University,

* Faculty of Agriculture, Seuz Canal University

The present study aimed to investigate the ability of different bacterial isolates inhabiting the oxidation pond 2 in 10th of Ramadan City to degrade certain industrial organic pollutants those directly and/or partially treated. Screening of the ability of each bacterial isolate to grow on minimal medium supplemented with different pollutants as a sole carbon source, was an effective method for determination and selection of degradative isolates for further studies. The combination of using consortia as well as pure cultures provides advantage over using only pure isolates. Screening the presence and separation of plasmids in the isolates with such capabilities using Pulsed Field Gel Electrophoresis (PFGE) technique was found to be an effective tool, specially for large plasmid DNA. Amplification of the toluene degrading gene (xylE gene) using PCR technique as well as radiolaballed xylE gene probe and hybridization proved the presence of xylE gene on a plasmid detected in a Flavobacterium sp. isolate and on the chromosomal DNA of a Flavobacterium meningosepticum isolate.
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