@article { author = {}, title = {Purification and Characterization of Extracellular α-amylase from Aspergillus niger K8}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {1-11}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.475}, abstract = {ASPERGILLUS NIGER K8 was selected from twenty-two fungal……isolates for α-Amylase production. The crude enzyme was partially purified and precipitated by salting out with ammonium sulphate. The fraction salted out with 60% ammonium sulphate saturation showed the highest specific α-amylase activity with 5.42 folds of purification than that of free extract. The optimum temperature for α-amylase enzyme activity was at 60°C. The enzyme was very stable at 60°C for 1 hr and retained more than 80% of its original activity. The optimum specific activity for A. niger K8 was in a narrow range of pH 5.0-6.0. Alpha amylase enzyme was stable at all pH tested. However, it retains more than 75% of its original activity for 1 h at pH value 5.5.}, keywords = { Aspergillus niger,α-amylase,precipitation,Characterization,Thermal stability,pH stability}, url = {https://ejbo.journals.ekb.eg/article_475.html}, eprint = {https://ejbo.journals.ekb.eg/article_475_6d3d06106bdf0201ad391d6030238e0e.pdf} } @article { author = {}, title = {Optimization of Biosorption Conditions of Hexavalent Chromium by Aspergillus niger and Spicaria silvatica Mycelial Mats, Using Taguchi Orthogonal Array}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {13-27}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.476}, abstract = {IN ORDER to maximize the biosorption efficiency, eighteen …...experiments were designed to investigate the potentialities of fungal biomass as a resistant and cost effective Cr+6 biosorbent. The influences of individual parameters as well as the interaction between them were studied using Taguchi statistical design. A group of statistical analysis that can define the relationships between the responses of independent variables were carried out. In the current study, it was detected that the biosorbed Cr+6 by A. niger and S. silvatica varied greatly among the 18 media used indicating the importance of optimization experiments in bioprocesses. In case of A. niger the ANOVA analysis of variance revealed that temperature, mycelium status, NaNO3 and agitation were the most significant factors influencing the Cr+6 biosorption .In S. silvatica, temperature, mycelium status, agitation and MgSO4 7H2O were the highly significant variables influencing Cr+6 biosorption .The design detected that the experimental values of biosorbed Cr+6 were in reasonable agreement with the predicted values and the model was significant. The optimized predicted medium from the software design for Cr+6 biosorption by A. niger and S. silvatica was (A) dead mycelium (B) sucrose (15 gl-1) (C) NaNO3 (1.5 gl-1) (D) MgSO4 7H2O (0.1 gl-1) (E)temperature (18 ºC) (F) pH (5) (G) cultivation (static)(H) incubation period (5days).}, keywords = {Biosorption,Hexavalent chromium, Aspergillus niger,Spicaria silvatica,Tannery pollution}, url = {https://ejbo.journals.ekb.eg/article_476.html}, eprint = {https://ejbo.journals.ekb.eg/article_476_2781591c270263f268af870ce65bddae.pdf} } @article { author = {}, title = {Cellulases Production by Free and Immobilized Aspergillus flavus}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {29-47}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.477}, abstract = {THE PRODUCTION of cellulase from some local fungal isolates ……..was studied. The results showed that Aspergillus flavus produced the highest cellulase activity (3.017 U/ml) under static condition. It also showed that the best carbon source for cellulase production was filter papers (7.0932 U/ml), and onion scales (6.396 U/ml) at a concentration 30 g/l medium. The Plackett-Burman design was studied for cellulase production from A. flavus showed that the optimizing medium achieved by the statistical design increased cellulase activity (11.699 U/ml) which approximately 2.3 times than that obtained from the basal medium. In addition, A. flavus biomass was entrapped in different gel materials, and the best one for producing cellulase was agar (8.22 U/ml), however, this activity was lower than that in free cultures. Moreover, A. flavus biomass was adsorbed on different porous materials, and the cultures adsorbed on luffa pulp exerted the highest cellulase activity (17.78 U/ml) which was higher than that produced by free cultures. By reusing the adsorbed A. flavus biomass on luffa pulp in seven successive times, the 4th cycle gave the highest cellulase activity (34.17 U/ml). It was concluded that A. flavus is a feasible candidate for the production of cellulase activity which can be applied in many industrial fields. The results also indicate the possibility of using different agro-wastes like onion scales as a sole carbon source for production of cellulase by A. flavus.}, keywords = {Keywords: Aspergillus flavus,Cellulase,Plackett-Burman design,Adsorption}, url = {https://ejbo.journals.ekb.eg/article_477.html}, eprint = {https://ejbo.journals.ekb.eg/article_477_41c3bbf19fc2242751db602763683f90.pdf} } @article { author = {}, title = {Characterization and Immunological Properties of Pseudomonas aeruginosa Hemolytic Phospholipase C}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {49-70}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.479}, abstract = {PHOSPHOLIPASE C (PLC) produced from 4 day age culture of ……….P. aeruginosa strain in inorganic phosphate starved liquid medium (pH7.2) at 35C. The enzyme was purified to electrophoretic homogeneity using gel filtration chromatography. Purified PLC had 6.2 purification fold and 28.2% yield. The purified enzyme had a molecular mass of 58.7 kDa. Alanine was the dominant amino acid with 13.1%. DNA sequence analysis of the PCR products amplified from P. aeruginosa confirmed the presence putative plcH gene (1.6 kb). The enzyme was completely inactive above 65C with Tm 42C. The enzyme activity was approximately stable at pH 8.5 to 10. The purified enzyme was characterized as a Zn2+-metallophospholipase C and also divalent ions Ca2+, Ba2+ and Co2+ were stimulators for its activity. The catalytic affinity of PLC enzyme towards phosphatidylcholine (PC) gave Vmax = 1.85 Umg-1 min-1; Km = 0.12 M and Kcat = 1.96 x 10-5 S-1. Purified PLC enzyme was detoxified by heating and completely lost its lethal activity on mice after 60 min at 65C. Immunologically, the titer of IgG antibodies in blood serum of New Zealand rabbits was appeared after 15 days of the last injection dose of fresh or heat detoxified enzyme by 1.15 and 1.21 fold respectively higher as compared to control followed by a decrease in the titer up to 45 days. The hematological parameters reflected a decrease in the RBCs, WBCs and hemoglobin in rabbits injected with fresh enzyme and there was significant change in chemistry of liver and kidney. In contrarily detoxified enzyme had no obvious changes in these parameters.}, keywords = {Pseudomonas aeruginosa,Phospholipase C, Antigenicity,}, url = {https://ejbo.journals.ekb.eg/article_479.html}, eprint = {https://ejbo.journals.ekb.eg/article_479_520f7dab7fa4194b630f5667cce86597.pdf} } @article { author = {}, title = {Gene Expression in Antifungal Resistant and Susceptible Isolates of Candida albicans}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {71-85}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.480}, abstract = {SUSCEPTIBILITY assays using white and opaque Candida albicans were performed against two antifungals: fluconazole (FLU) and terbinafine (TRB). The microdilution method (NCCLS M27-A2) was used for determination of the MIC90. It was found that FLU and TRB were active antifungal drugs against C. albicans either in white or opaque forms but FLU more efficient than TRB.The expression of five resistance genes was measured by RT-PCR after treatment of C. albicans with both FLU and TRB. The results indicated that Candida drug resistant gene CDR1 was expressed in susceptible and resistant isolates. However, Candida drug resistant gene CDR2, Candida multidrug resistant gene CaMDR1 and ergosterol resistant gene ERG11 were up regulated in only resistant C. albicans against FLU and TRB. Fluconazole resistant gene FLU1 in C. albicans not expressed at all antifungal treatments.}, keywords = { Candida albicans,antifungal drugs,resistance genes}, url = {https://ejbo.journals.ekb.eg/article_480.html}, eprint = {https://ejbo.journals.ekb.eg/article_480_f2f35ac785b83ca1d2e9ae3481cdc319.pdf} } @article { author = {}, title = {Pollen Morphology of some Species of Genus Ficus L. (Moraceae) from Egypt}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {87-102}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.481}, abstract = {IN THE PRESENT work, the pollen morphological characters were extensively studied in 17 taxa from genus Ficus (Moraceae), based on examination with light and scanning electron microscopy. The studied taxa represent three subgenera (Ficus, Sycomorus and Urostigma), collected from three Egyptian Botanical Gardens (Orman, Ain-Shams and Zoo-garden). The obtained results of fundamental and evolutionary significance were: pollen size (less than 20 μm), pollen shape (circular or elliptic), pollen class (vary from di- to triporate), and the pollen surface sculpture (psilate or finely scabrate). The dendrogram produced from the cluster analysis of the characters of pollen grains have been discussed, and shed light on the relationships, similarities and dissimilarities between the studied taxa. Pollen data only does not support macromorphological evidence for the identification of Ficus species.}, keywords = {Moraceae, Ficus,Pollen,Morphology,Taxonomy,Egypt}, url = {https://ejbo.journals.ekb.eg/article_481.html}, eprint = {https://ejbo.journals.ekb.eg/article_481_3d42f4ed15a168ffaafe6bee9c787d20.pdf} } @article { author = {}, title = {Polymorphic Analysis and Genetic Similarity of Genus Ficus L. (Moraceae) in Egypt}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {103-120}, year = {2013}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2013.482}, abstract = {NINTEEN SPECIES belonging to genus Ficus were obtained ……… from three Egyptian gardens to study the information derived from ISSR fingerprinting, and to estimate the level of polymorphism and genetic similarity. Five ISSR primers were used to estimate the level of polymorphism among the different species. This study indicates that, the total number of bands detected by the different ISSR primers was 229 all of them were polymorphic, representing a level of polymorphism of 100% and an average number of 46 polymorphic bands per primer. The ISSR analysis revealed the highest genetic similarity (85%) between F. afzelii and F. benghalensis, while the lowest genetic similarity (58%) was observed between F. carica and F. sycomorus. The obtained results clearly revealed a high level of similarity among the investigated Ficus species, ensuring the highest degree of homology and the narrow genetic background of these species. The two studied taxa of subgenus Ficus, viz., F. carica and F. deltoidea were widely separated and showed relations with the taxa of subgenus Urostigma. Also, the three studied taxa of subgenus Sycomorus possessed relations with members of subgenus Urostigma.}, keywords = { Ficus,ISSR,Polymorphism,fingerprinting}, url = {https://ejbo.journals.ekb.eg/article_482.html}, eprint = {https://ejbo.journals.ekb.eg/article_482_83baf6ed38d3def2eff139bc16d4588d.pdf} } @article { author = {}, title = {Influence of Seaweed Extracts (Sargassum dentifolium or Padina gymnospora) on the Growth and Physiological Activities of Faba Bean and Wheat Plants Under Salt Stress}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {121-135}, year = {2013}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2013.483}, abstract = {THE CHANGES of growth and some physiological parameters in faba bean (Vicia. faba L. cv. Masr-1) and wheat (Triticum vulgare L. cv. Sakha-94) treated with NaCl levels and seeds soaking for 12 hr in 1% seaweed water extracts from Sargassum dentifolium or Padina gymnospora collected from the red sea, Hurghada, Egypt were studied. Fresh, dry mass and photosynthetic pigments contents (Chl.a, Chl. b and Car.) of both plants significantly decreased in response to salt stress. The highest salinity levels (150 and 200 mM NaCl) resulted in injurious effects led to death of the tested plants (faba bean and wheat, respectively). Salinity induces a significant decline in the activity of ascorbate peroxidase (APX) of faba bean and peroxidase (POD) of wheat. On the other hand, there was marked increase in the activity of superoxide dismutase (SOD), catalase (CAT), of the two plants, POD of faba bean and APX of wheat compared to untreated plants. Application of 1% aqueous extract of S. dentifolium or P. gymnospora by seed soaking was accompanied by stimulation in growth, photosynthetic pigments and the activity of antioxidant enzymes. The higher activity was observed for extract of S. dentifolium. In contrast, treatment with seaweed water extracts resulted in significantly decreased in MDA content, which increased under salinity stress. All the previous findings suggested the possibility that seaweed water extracts may play an important role in increasing plant resistance by stimulating the antioxidant enzyme system which associated with a marked retardation in the MDA content.}, keywords = {Antioxidant, Sargassum dentifolium, Padina gymnospora,Salinity, Lipid peroxidation}, url = {https://ejbo.journals.ekb.eg/article_483.html}, eprint = {https://ejbo.journals.ekb.eg/article_483_677d23dff7ab475fca44f53d1bdbbb71.pdf} } @article { author = {}, title = {Purification and Characterization of Streptomyces canarius L- Glutaminase and its Anticancer Activity}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {137-157}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.484}, abstract = {L-GLUTAMINASE produced by Streptomyces canarius FR …….(KC460654) was purified to homogeneity with an apparent molecular mass of 44 kDa. The purified enzyme was 17.9 fold with a final specific activity 132.2 U/mg protein and 28% yield recovery. The purified L- glutaminase showed a maximal activity against L-glutamine when incubated at pH 8.0 and 40°C for 30 min. The enzyme maintained its stability at wide pH range for 5.0- 11.0 and is thermally stable up to 60°C with Tm value 57.5°C. The enzyme had high affinity and catalytic activity for L- glutamine (Km 2.4 mM, Vmax 28.1 U/mg/min), followed by L- asparagine and L-aspartic acid. In vivo, the purified enzyme showed no obvious changes in liver and kidney functions. Also, it has a normal effect in all hematological parameters except slight effect on RBCs and levels of platelets as shown after 10 days of rabbit’s injection with purified enzyme. Interestingly, it showed slight effect on the tested renal and liver tissues comparing with negative control. The anticancer activity of the purified enzyme was determined against five types of human cancer cell lines using MTT assay in vitro. The tested enzyme had a high efficiency against Hep-G2 cell (IC50, 6.8 μg/ml) and HeLa cells (IC50, 8.3 μg/ml), while the growth of MCF-7 cells was not affected. On the other hand, the tested enzyme had a moderate cytotoxic effect against HCT-116 cell (IC50, 64.7 μg/ml) and RAW 264.7 cell (IC50, 59.3 μg/ml).}, keywords = {L-glutaminase,Anti-cancer,Cytotoxicity,MTT assay}, url = {https://ejbo.journals.ekb.eg/article_484.html}, eprint = {https://ejbo.journals.ekb.eg/article_484_48d6b47a23de11af68ba09b3e10047a0.pdf} } @article { author = {}, title = {Biosorption of Hexavalent Chromium by Bacteria Isolated from Salt Rich Tannery Wastes}, journal = {Egyptian Journal of Botany}, volume = {54}, number = {1}, pages = {159-170}, year = {2014}, publisher = {National Information and Documentation Center (NIDOC), Academy of Scientific Research and Technology (ASRT)}, issn = {0375-9237}, eissn = {2357-0350}, doi = {10.21608/ejbo.2014.485}, abstract = {IN THIS STUDY, two isolates capable of biosorption of Cr(VI) were isolated from chromium rich effluent treatment plant located at Magra Al-Oyoon, Old Cairo, Egypt. The abundance of bacteria residing in tannery waste water with high metal content was studied. Seventy-two bacterial isolates were recovered by direct plating; two of them were resistant to high chromium concentration (up to 30 mmol chromate). According to the morphological, biochemical and the 16S rRNA sequence analysis they were identified as Bacillus tequilensis and Planococcus citreus .The atomic adsorption spectroscopy showed that reduction of chromate content in the cell free supernatant was 59.8% and 45.8% for Bacillus tequilensis and Planococcus citreus, respectively, after 24 hr of incubation at 30°C. Moreover, both scanning electron micrographs and EDX analysis showed accumulation of chromate on both isolates. Bacillus tequilensis and Planococcus citreus had high potential for hexavalent chromium removal and can be used for detoxification of waste containing hexavalent chromium along with other heavy metals in media with high salt concentration.}, keywords = {Chromium,Heavy metals,Biosorption,SEM-EDX}, url = {https://ejbo.journals.ekb.eg/article_485.html}, eprint = {https://ejbo.journals.ekb.eg/article_485_a4dd86855092a71ffd8ca827beb6b508.pdf} }