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CYTOGENETIC EFFECTS OF Myrtus communis AND Plantago albicans INFUSIONS ON BEAN ROOT-TIP AND MICE BONE-MARROW CELLS Texte intégral
2005
M.H.; Al–Saadi, | Benkhayal F.A. | Al–Saadi A.H.
In Libya the plants Myrtus communis and Plantago albicans are commonly used in folk medicine to treat various diseases. However, there are a large number of plant compounds which can cause many aberrations in genetic material. This study was carried out to investigate any possible cytotoxic and mutagenic effects for M. communis and P. albicans on mitotic criteria of cell cycle and chromosomes. Two infusion concentrations were prepared for each plant, one of them was used as folk medicine (o.25 mg/ml) and other as to 10 times of this value (2.5 mg/mL). Bean (Vicia faba, L.) root-tip cells (RTC) and Balb / C mice (Mus musculus) bone-marrow cells (BMC) were used as test systems. The M. communis infusions at both concentrations and the P. albicans infusion at the lower concentration had no statistically significant depressive effect on mitotic criteria of RTC. Where as significant depressive effect on these criteria of RTC was found for the high concentration of P. albicans as compared with a negative control. No significant effect on the induction of chromosome aberrations and the rate of mitotic index of BMC was found by using infusions of P. albicans and M. communis as compared with control.
Afficher plus [+] Moins [-]DETERMINATION OF WATER REQUIREMENTS AND IRRI-GATION SCHEDULING FOR DATE PALM OFFSHOOT Texte intégral
2005
A Al-Humaid | Kassem M.A.
The current study was carried out at the Agricultural and Veterinary Research Station, Faculty of Agriculture and Veterinary Medicine, Qassim University, Kingdom of Saudi Arabia during the two seasons 2003/2004 and 2003/2004. The objectives of this study are to investigate the effect of irrigation scheduling methods with different amounts of applied water on date palme offshoot growth, Determination offshoot consumptive use, crop coefficient, actual water requirements and the suitable soil moisture tension in the root zone before irrigation. The irrigation was scheduling by three methods, evapotranspiration calculation method, soil moisture depletion method and farmer method (control). The evapotranspiration calculation method (ETo) included ten treatments as a percentage of evapotranspiration (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0 ETo). The soil moisture depletion method included five treatments of soil moisture depletion as a percentage of field capacity (50%Fc, 60%Fc, 70% Fc, 80% Fc and 90% Fc). The results showed that scheduling irrigation of the offshoot by evapotranspiration calculation method (ETo) or by soil moisture depletion method, the amount of applied water decreased and the offshoot growth and the water use efficiency increased; compared with the farmer scheduling method. The daily and seasonal gross irrigation requirements for date palm offshoots were 51.3 l/day and 2191 m3/hec.year, while the farmer applied 19960 m3/h.year. So, the farmer added seven times as much as the actual gross irrigation requirements. The maximum water use efficiency were 2.5 kg/m3 and 1.44 kg/m3 for the treatments 0.1 ETo and 50% Fc, respectively. The suitable soil moisture tension in the root zone before irrigation were 21.5 to 22 C-bar and 22.5 to 23 C-bar for 60 cm and 90 cm depths, respectively.
Afficher plus [+] Moins [-]ANTIOXIDANT ACTIVITY OF SOME SAGE LEAVE EXTRACTS Texte intégral
2005
A. F. | Al-Saadi A.H. | Al-Saadi M.H. | Hamad Wessal H.
Sage leaves were successively extracted with water, chloroform: methanol (2:1, v/v), n- hexane, benzene, diethyl ether, chloroform, chloroform: methanol (8:2, v/v) and dichloromethan. Antioxidant activities were detected using two methods :1. The carotene spray method and 2.Measuring the coupled oxidation of β–carotene and linoleic acid. Generally, all extracts had antioxidant activities when tested by the first method. By means of the second method, the extracts of water, diethyl ether and chloroform : methanol( 8:2, v/v ) showed the greatest antixidant activities , followed by the extracts of organic and aqueous phases ( which were extracted with chloroform: methanol, 2:1, v/v), dichloromethan and chloroform, while the n- hexane and benzene extracts showed low activities.
Afficher plus [+] Moins [-]EFFECT OF BIOMPHALARIA ALEXANDRINA SNAILS INFECTED BY BACILLUS THURINGIENSIS KURSTAKI ON THREE SUCCESSIVE GENERATIONS OF SCHISTOSOMA MANSONI Texte intégral
2005
Samia El-Bardicy | Menerva Tadros | Sherif Hafez
The effect of infection of Biomphalaria alexandrina snails with Bacillus thurin-giensis kurstaki on various stages of Schistosoma mansoni life cycle was studied for three successive generations. Thus, two groups of snails were exposed to a sublethal concentration of the bacteria (0.08 gm/L water) containing 32000 IU/mg, for one week and to schistosome miracidia. One group was exposed to the miracidia before bacterial infection, while the other group to the miracidia after the bacterial infec-tion. Cercariae produced from each group of snails were used to infect albino mice. The infection of snails and mice with the parasite was repeated for three generations of the parasite. In the first case, data obtained show that the schistosome infection rate of snails was considerably reduced being 60%, 18%, and 66.6% versus 90 % , 92% and 90% in untreated control snails in the three generations of the parasite, re-spectively. Meanwhile, the mean prepatent period was extended being 29.1 4.3 days, 33 1 days and 38.5 2.5 days versus 27 days in the control group. The num-ber of worms recovered from infected mice showed reduction of 52 %, 78.4% and 58.6%, respectively. In the second case, the infection rate of snails was 40%, 16% and 73.7% for the three successive parasite generations and the prepatent period was 32 1 days, 32 2.3 days and 35 2.8 days, respectively. The reduction percentage of the recovered worms was 34.8, 73.6 and 72.9 in the sccessive generations, respec-tively. The present results prove that infecting B.alexandrina snails with a sublethal concentration of B. thuringiensis kurstaki bacteria exhibits clear negative effect on the transmission of S. mansoni in three successive generations. So, it could be rec-ommended to use B. thuringiensis kurstaki as a potential biocontrol agent against S. mansoni.
Afficher plus [+] Moins [-]DIAGNOSING THE NUTRITIONAL STATUS OF APPLE ORCHARDS AT SOUTH OF JORDAN Texte intégral
2005
F Al-Nasir | K Al-Absi
A test survey was conducted to determine the nutritional status of apple trees grown at four highly productive orchards in south of Jordan. Leaf and soil samples were taken from each orchard, and analyzed for the concentrations of macro- and micronutrients. Soils of Al-Shoubak tend to have high pH, low organic matter and high CaCO3 contents. The results showed that soil concentrations of N, K, Fe, Mn, Zn and Cu varied widely among the orchards. No deficiency or hunger signs of N, P, K, Mn and Zn nutrients were observed at any of the localities since concentrations of leaf nutrients were generally within the sufficient range, indicating adequate lev-els of fertilization applied to the trees. The leaf analysis has shown that Cu deficien-cy is found in some apple orchards. Soils and leaf nutrient levels were generally not well correlated with one another. The only highly significant correlation was be-tween soil P and leaf N. However, positive relations were observed among leaf P and Mn, Fe and Mn, Fe and Zn, and Mn and Zn contents.
Afficher plus [+] Moins [-]IN VITRO PROPAGATION OF THREE ALMOND CULTIVARS AND THE ALMOND – PEACH HYBRID ROOT-STOCK“HANSEN” Texte intégral
2005
A El-Hammady | Wafaa Wanas | A Abd El-Hamid | M El-Salem
Stem node explants of three almond (Prunus dulcis Mill) cultivars (Om – Elfahm, M-Dalt and Ne Plus Ultra) and the hybrid rootstock “Hansen” cv. were suc-cessfully established and proliferated on Murashige and Skoog medium (MS) sup-plemented with benzyl adenine (BA) at 0.0 - 2.0 mgl -1 and indol butyric acid (IBA) at 0.0 - 0.1 mgl-1 .The highest bud development percentage of stem node explant was obtained with medium contained BA at 2 mgl-1 with or without IBA at 0.1 mgl-1 for M – Dalet and Ne Plus Ultra almond cultivars compared with other treatments. The longest shoot during establishment stage was recorded by “Hansen” rootstock cultured in MS with BA at 2.0 mgl-1 plus IBA at 0.01 mgl-1.Using BA at 1.0 mgl-1 plus IBA at 0.1 mgl-1 and BA at 2.0 mgl -1 plus 0.05 or 0.1 mgl -1gave the highest number of proliferated shoots for Om – Elfahm, M-Dalt and Ne Puls Ultra cvs. and “Hansen”, respectively in the 3rd subculture. The best average proliferated shoot length was achieved with medium supplemented with BA at 1.0 mgl-1 plus IBA at 0.05 mgl-1 or 0.1 mgl-1 for M-Dalt, Ne Puls Ultra and “Hansen” respectively, where-as, using BA at 2.0 mgl -1 plus IBA at 0.1 mgl -1 recorded the longest average prolif-erated shoot for Om- Elfahm cultivar. Microshoots were rooted in modified Bourgin and Nitsch medium supplemented with IBA or NAA at 1.0 mgl-1 only or combination (0.2 IBA mgl-1 + NAA 0.4 mgl-1, IBA 0.4 mgl-1 + NAA 0.8 mgl-1 and IBA 0.5 mgl-1 + NAA 1.0 mgl-1). The large callus (more than 10 mm diameter) was recorded with “Hansen” rootstock and Om – Elfahm treated by IBA at 0.4 mgl -1 plus NAA at 0.8 mgl -1. The greatest rooting percentage (66.67%) was obtained with medium contained IBA at 0.2 or 0.4 mgl-1 plus NAA at 0.4 or 0.8 mgl-1 for “Hansen” rootstock and Ne Plus Ultra shoots.
Afficher plus [+] Moins [-]UTILIZATION OF CORN GERM AND SUNFLOWER SEEDS AS A NEW SOURCES OF LECITHINS AND THEIR MODIFIED FORMS IN MANUFACTURE OF CARAMEL Texte intégral
2005
Y Kishk | Salwa Abo-El-Fetoh
Fractionation and acylation by ethyl alcohol and acetic anhydride were carried out to produce a modified corn germ and sunflower lecithins from their crude leci-thins. Emulsification activity and emulsion stability indices (EAI & ESI) were de-termined at different pH values (2, 4, 6, 8 and 10) for commercial and studied leci-thins. EAI was significantly improved in modified lecithins in comparison to crude lecithins with increasing rate of 52.9 and 58.6 % for corn germ and sunflower etha-nol soluble fraction lecithins and 15.6 and 20.5 % for acylated corn germ and sun-flower lecithins, respectively. The changes in ESI after times of 20, 40 and 60 min. showed a higher stability of emulsions prepared using modified lecithins which were closed to that prepared using commercial soy lecithin. Caramel was prepared using commercial soy, corn germ, sunflower lecithins and their modified forms. Hardness of tested samples was determined in the start of storage time while, acid value, per-oxide value, fatty acid pattern and sensory attributes were determined during storage period at room temperature for six months. Data revealed insignificant difference in caramels hardness. Samples contained crude sunflower; acylated corn germ and sun-flower lecithins were more sensitive to oxidation while, those prepared using com-mercial soy, crude corn germ, ethanol soluble fraction of corn germ and sunflower lecithins showed higher oxidative stability with significant differences (P<0.05). Concerning sensory evaluation, both ethanol soluble fractions and acylated lecithins produced high quality caramels not differed (P>0.05) to control one that contained commercial soy lecithin. The quality and quantity of lecithin that used in prepared of caramel samples played a major role in their characteristics. The modified corn germ and sunflower lecithin forms were preferred than the raw lecithins owing to their higher emulsifying activity and lesser quantity used. The ethanol soluble lecithins fraction, especially of corn germ can be competitive to the commercial soy lecithin in all emulsified food products.
Afficher plus [+] Moins [-]EFFECT OF TOOTH PICK (AMMI visnaga L.) SEED EXTRACTS ON THE RICE WEEVIL SITOPHILUS oryzae (COLEOPTERA : CURCULIONIDAE) Texte intégral
2005
Salwa Ahmed | Nadra Al-Moajel
Seeds of the tooth pick plant (Ammi visnaga L.) were extracted by organic sol-vents of different polarities, and tested for their toxic effect on Sitophilus oryzae in-festing wheat grains. Toxicity of chloroform extract, was the most potent, at both Lc50 and Lc95 levels (i.e. 3240 and 8730 ppm). Reproductive potential of treated weevil were strongly affected as no progeny were obtained when treated with either Lc50 or Lc95 with A. visnaga. Extracts treatment at Lc95 level organic extract gave protection up to 12 weeks for petroleum ether and chloroform, and 9 weeks when acetone was used for extraction. All tested extracts reduced grain germination at the end of 14 weeks storage period. Also, treated wheat grains with tooth pick extracts reduced the weight loss of grains.
Afficher plus [+] Moins [-]MORPHOLOGICAL AND ANATOMICAL VARIATIONS OF ANABASIS ARTICULATA ECOTYPES IN EGYPT Texte intégral
2005
Azza Khafagi | A. Marei | Sahar Mohamed
The present study has been carried out on ten stands of Anabasis articulata in Egypt. The relationships between the studied Anabasis articulata stands have been demonstrated as dendrogram based on the morphology, anatomy and some chemical constituents of the plants. Four characteristic ecotypes of Anabasis articulata have been recognized: (i) xerophytic ecotype in the stands of Belbase desert and Sudr El Hytat-Nekhl Road, (ii) xero - halophytiç ecotype in the stands of the Eastern Desert, Sinai Desert, Kattamia-Ain Sukhna Road, Isthmic desert (Fayid), Adabia and Saint Katherine, (iii) halophytic ecotype in the stands of the Red Sea Costal region, Ras Sudr and Hammam Faraon, Sinai and (iv) halo-xerophytic in the stands of the Nekhl-El Hasana and El Hasana-El Quseima Roads. These ecotypes differ, remark-ably, morphologically, anatomically and chemically. This may be due to the varia-tion in climatic and soil characteristics of the habitats
Afficher plus [+] Moins [-]CULTURAL, MORPHOLOGICAL, PHYSIOLOGICAL AND MOLECULAR STUDIES ON SOME STREPTOMYCETE ISOLATES Texte intégral
2005
H Abdel-Fattah
In this study, three isolates of Streptomyces isolated from Egyptian soil at Giza Governorate and belonging to red series were identified based on their cultural, morphological and physiological characters. According to the key proposed by Pridham and Tresner (1974), the experimental isolates ST55, ST71 and ST86 ap-peared to be related to S. lincolnensis, S. venezuelae and S. umbrinus, respectively. In addition, random amplified polymorphic DNA (RAPD)-polymerase chain reac-tion (PCR) was used to amplify the DNA genome of the three applied isolates and an identified strain to determine their fingerprints. This was carried out using 10-decamer oligonucleotides, i.e., OP-A02, OP-D01, OP-D02, OP-D05, OP-D06, OP-D07, OP-D08, OP-D11, OP-D18 and OP-D20. The PCR amplified products were detected by electrophoresing on 1.5% agarose gel and visualized by staining in eth-idium bromide and UV trasilluminator. Results showed that the same oligonucleo-tide flanking fragments differed from one isolate to another with different sizes. Monomorphic and polymorphic fragments were amplified confirming the molecular relationships as well as the genetic diversity between the four applied strains of Streptomyces. Based on the statistical analysis of RAPD-PCR polymorphisms a de-gree of similarities ranged from 33.9 to 59.2 % was found. Furthermore, frag-ment(s), whatever absent or present, were found to be unique molecular markers and could be used for characterization of some isolates. This result supported the idea for using the RAPD-PCR technique for classification of Streptomyces isolates.
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