@article { author = {Salem, Olfat}, title = {THE EFFECT OF CHLORAMPHENICOL AND COPPER ON THE CELL ULTRASTRUCTURE OF SCENEDESMUS SP.}, journal = {Egyptian Journal of Phycology}, volume = {15}, number = {1}, pages = {1-10}, year = {2014}, publisher = {The Egyptian Phycological Society}, issn = {1110-8649}, eissn = {2735-3826}, doi = {10.21608/egyjs.2014.115219}, abstract = {The present study aimed to evaluating the effect of chloramphenicol (CAP) and copper (CuSO4) on the cell ultra-structure of Scenedesmus sp. Three different concentrations of CuSO4 (10-3, 10-4, 10-5 M) and two of CAP (0.25 and 0.5%) were added to exponentially growing algal culture (107 cells ml-1) for 24 hrs. Cells treated with 10-3 M CuSO4 and 0.5% chloramphenicol which gave high amount of cell lyses were chosen for examination by electron microscopy. Transmission electron microscopy photographs of Scenedesmus cells treated with CuSO4 showed deformation of the chloroplasts, while numerous vesicles were observed in the cytoplasm. The three–laminar sheath (TLS) and the reticulate layer (RL) had no differences in comparison with control. On the other hand, tubular spikelets had no distinct shape compared with the control. The inner layer of cell wall (cellulose layer) showed shrinkage in thickness. Moreover, cells treated with 0.5% CAP showed that chloroplast thylakoids were reduced in size and number, disorganization, shrinkage in all protoplasmic components and increasing in the number of vacuoles and cellulose layer thickness. These results may help in understanding the effect of some toxins such as antibiotics and heavy metals on the cell structure of microalgae.}, keywords = {antibiotics,Cell Ultrastructure,Heavy metals,microalgae,Scenedesmus}, url = {https://egyjs.journals.ekb.eg/article_115219.html}, eprint = {https://egyjs.journals.ekb.eg/article_115219_d9c939832368690e92cff0b16c005035.pdf} } @article { author = {Farag, Mohamed and Abd El Fatah, Hesham and Shabaraa, Hanaa and Shaaban, Hanan}, title = {EFFECTS OF GROWTH OF SOME CYANOPROKARYOTA AND DIATOM SPECIES ON THE GROWTH OF TWO MOSSES}, journal = {Egyptian Journal of Phycology}, volume = {15}, number = {1}, pages = {11-20}, year = {2014}, publisher = {The Egyptian Phycological Society}, issn = {1110-8649}, eissn = {2735-3826}, doi = {10.21608/egyjs.2014.115225}, abstract = {Cyanoprokaryotic taxa Nostoc paludosum Kützing ex Bornet & Flahault and Nostoc punctiforme (Kützing) Hariot may have allelopathic effects on two moss taxa, Bryum subapiculatum Hampe and Funaria hygrometrica Hedwig, grown in vitro under 66% and 99% percentages of soil water holding capacity. Nostoc filaments destroyed protonema of B. subapiculatum and arrested gametophores development of F. hygrometrica under these conditions. Colonies of the diatom Navicula cryptocephala var. veneta (Kützing) Grun. grew in a large amount and delayed the growth of B. subapiculatum.}, keywords = {Allelopathy,bryophytes,Bryum,Funaria,Navicula,Nostoc}, url = {https://egyjs.journals.ekb.eg/article_115225.html}, eprint = {https://egyjs.journals.ekb.eg/article_115225_7679a3ea2fbea5853b10cf8528062dd3.pdf} } @article { author = {Shafik, Hesham and Saad, Marwa and El-Serehy, Hamed}, title = {IMPACT OF NITROGEN REGIME ON FATTY ACID PROFILES THAT PRODUCED BY DESMODESMUS QUADRICAUDATUS AND CHLORELLA SP.}, journal = {Egyptian Journal of Phycology}, volume = {15}, number = {1}, pages = {21-37}, year = {2014}, publisher = {The Egyptian Phycological Society}, issn = {1110-8649}, eissn = {2735-3826}, doi = {10.21608/egyjs.2014.115230}, abstract = {Microalgae have emerged as one of the most promising sources for fatty acids production. Since the various fatty acid profiles (chain length, degree of unsaturation, and branching of the chain) of the different sources influence biodiesel fuel properties, it is important to possess data on how the presence of NaNO3 as nitrogen source can influence the profile of produced fatty acids from algae. The fatty acid profiles of Desmodesmus quadricaudatus and Chlorella sp. were detected in batch cultures experiments. BG-11 nitrogen free medium or the medium contained 1.5g NaNO3l-1 were used in this investigation. At late stationary growth phase in nitrogen free medium, Chlorella sp. produced 58.39% saturated fatty acids and 41.60% unsaturated fatty acids. While in medium contained 1.5g NaNO3 l-1 produced 62.08% saturated fatty acids and 37.92% unsaturated fatty acids. In nitrogen free media D. quadricaudatus produced 66.92% saturated fatty acids and 33.07% unsaturated fatty acids. While in cultures contained 1.5g NaNO3 l-1 produced 51.62% saturated fatty acids and 48.37% unsaturated fatty acids. The fatty acid profile of Chlorella sp. that isolated from Egyptian water body and grown in nitrogen free media may suitable for biodiesel production. The results discussed and compared to fatty acids profiles produce by other algal species.}, keywords = {Batch cultures,Chlorella sp,Desmodesmus quadricaudatus,fatty acid,Nitrogen regime}, url = {https://egyjs.journals.ekb.eg/article_115230.html}, eprint = {https://egyjs.journals.ekb.eg/article_115230_47729ca7c1935e8d8c95431c59b91144.pdf} } @article { author = {Abd El-Karim, Mohamad}, title = {EPIPELIC ALGAL DISTRIBUTION IN ISMAILIA CANAL AND THE POSSIBLE USE OF DIATOMS AS BIOINDICATORS AND A BIOMONITORING TOOL}, journal = {Egyptian Journal of Phycology}, volume = {15}, number = {1}, pages = {39-58}, year = {2014}, publisher = {The Egyptian Phycological Society}, issn = {1110-8649}, eissn = {2735-3826}, doi = {10.21608/egyjs.2014.115232}, abstract = {Sixteen stations were sampled (four successive seasons) during 2011. Physical and chemical characters of water in combination with surface sediment were sampled from Isamilia Canal and its branches. Diatoms dominated the epipelon community, whereas chlorophytes and cyanobacteria were rarely present. One hundred sixty-seven epipelic species were recorded. Diatoms were dominated by the centric diatoms Cyclotella spp. and Aulecosiera spp. Most frequent diatom species underwent multivariate analysis of TWINSAPN to clarify the classification of diatom species and CCA to correlate diatom species to the most effective environmental parameters. Most species were positively affected by eutrophication, PO4 and NH3, and seasonal related factor, temperature, whereas they were negatively affected by pH and SiO2. The applicability of Trophic Diatoms Index (TDI) was tested in the area of study. The results of the TDI revealed that the majority of the canal stations were in the acceptable ring but showed non-significant relation with the eutrophication parameters. The application of diatoms based indices developed in foreign countries cannot be applicable in egyptian environment and the development of indices based on the egyptian ecoregions is very obligatory.}, keywords = {Isamilia Canal,Epipelic diatoms,water quality,Bioindicators,Biomonitoring}, url = {https://egyjs.journals.ekb.eg/article_115232.html}, eprint = {} } @article { author = {Zeid, Ibrahim and Ghazi, Safia and El Semary, Nermin and Abd El-Sattar, Amira}, title = {COUNTERACTING INHIBITORY EFFECT OF SALINITY STRESS ON COWPEA GERMINATION USING CYANOBACTERIAL EXTRACTS}, journal = {Egyptian Journal of Phycology}, volume = {15}, number = {1}, pages = {59-76}, year = {2014}, publisher = {The Egyptian Phycological Society}, issn = {1110-8649}, eissn = {2735-3826}, doi = {10.21608/egyjs.2014.115236}, abstract = {The response of cowpea seeds grown under salinity-induced stress conditions to different cyanobacterial extracts of two strains (Aphanizomenon flos-aquae and Phormidium sp.) was studied during seed germination. The results indicated that aqueous extract was more stimulating to germination than organic extract where higher levels of germination percentage, enzymatic activity, nucleic acid, protein and total soluble sugars contents were obtained. In addition, the indicators of stress such as proline content, lipid-peroxidation and relative permeability of the root membranes were lower than the organic extract. Application of aqueous cyanobacterial extracts of Aphanizomenon flos-aquae and Phormidium sp. stimulated seed germination and the metabolic activities of salt-stressed and unstressed seeds, while the lipid-peroxidation and relative permeability of the root membranes were reduced. Therefore, aqueous algal extracts alleviated the harmful effect of salinity stress on seed germination. This can be used on a vast scale as an inexpensive and eco-friendly farming policy to counteract the hazardous effect of salinity on plants especially during the critical period of seed germination where salinity can inhibit it either partially or completely.  }, keywords = {Cyanobacteria,Germination percentage,enzymatic activity,metabolic activities,lipid-peroxidation,relative permeability}, url = {https://egyjs.journals.ekb.eg/article_115236.html}, eprint = {https://egyjs.journals.ekb.eg/article_115236_40a803909102330856f10d71d97e127c.pdf} }