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Harvesting Microalgae by Chitosan as Sustainable Biopolymer
2023
Obyd, Ola | Abou Hadid, Ayman | Selim, Shawky | El-Arabi, Tarek
This study aimed to use the organic polymer, chitosan, as a flocculant for harvesting microalgae Chlorella. sp. Various polymer concentrations were tested. Within three min, 50 mg/L of chitosan showed the highest efficiency (98.9±0.5%), at pH 6.3, while the lowest efficiency (86.7±0.5%) was observed at pH 7.5. Harvesting efficiency in this study was chitosan concentration dependent. The present study showed that chitosan can be a promising and sustainable solution as an organic source and environmentally friendly flocculant. Additionally, it has excellent harvest productivity and requires minimum effort for quick outcomes.
Показать больше [+] Меньше [-]Effect of Total Mixed Rations Versus Traditional Feeding of Concentrate and Roughage Rations on Dairy Cattle Performance in Sudan
2023
Elhag, Mahgoub | Mohammed, Bedria | Sayed, Mohmed | Abdulla, Mohmed | Abdulla, Mayser | Abakar, Yassin
Dairy cattle in Sudan are traditionally fed on separate concentrate and roughage diets. Because of the high cost of forages, feeding strategies should be attempted to reduce feeding costs. A traditional dairy ration (As-fed), composed of 49% sorghum grains (SG), 29.4% groundnut seed cake (GSC), 19.6% wheat bran (WB), 1% limestone (LS) and 1% salt (NaCl), was used as a control. The test ration was a total mixed ration (TMR) composed of 40% SG, 23% groundnut seed hulls (GSH), 20% GSC, 15% WB, 1% LS and 1 % NaCl. The control traditional ration was fed at 10 Kg/cow/day together with 7 Kg sorghum chaff. Two levels of TMR were used with alfalfa hay (AH); (17 Kg TMR + 1 Kg AH/cow/day and 15 Kg TMR + 2 Kg AH. Three cross-bred dairy cows (European x Local) were used with the feeding regimes in a 3x3 Latin square design. Cows consumed similar amounts of DM, CP and ME and produced similar quantities of milk (P > 0.05). TMR had no effects (P > 0.05) on the composition of milk. The cost for TMR was decreased by 19%.TMR was thus effective in reducing feeding costs without affecting milk production and composition.
Показать больше [+] Меньше [-]Phylogenetic Evolution of Egyptian Goat Breeds “Capra Hircus” Based on Mitochondrial DNA D-Loop Sequence
2023
Bherey, Eslam | Hassan, Heba | Ellbadawy, Adel | El_Maghraby, Mahmoud | Moghazee, Mona
The population genetic and molecular evidence of the Arabian goat breed's phylogenetic standing (Capra hircus) is misunderstood, and little is known about genetic diversity in this species. Despite their importance in producing meat and milk, as well as their capacity to endure difficult conditions with little access to food and water, goats are the most common animal in Arab countries. We investigated the phylogenetic history and demographics of domestic goats by sequencing a hypervariable segment of the mtDNA reference region for Baladi, Demuscous, and Zaraibi breeds, as well as sequences retrieved from 16 Arab countries. Three significantly divergent lineages associated with Africa and the Middle East were identified through phylogenetic analysis of the investigated strains of Egyptian goats' mtDNA D-loop region. All Egyptian goats were allocated to lineage A, which is made up of 445 different haplotypes, including Egyptian and Arabian goats. Diversity in haplotypes and in nucleotides for each Arabian goat population was calculated separately and estimated to be 0.99835 and 0.02576, respectively. Finally, we suggest that all goat lineages descend from a single clan. The ancient world's migration and travel may have influenced goat diversity, implying that goats had multiple matrilineal forebears
Показать больше [+] Меньше [-]Molecular Genetic Studies on Honeybees in Response to Some Environmental Stresses
2023
Mohamed, Rehab | Ebeed, Naglaa | Fahmy, Khalid | Alsenosy, Naima | Abdelmegeed, Sawsan
The honeybee, Apis mellifera, is a widespread pollinator insect. Colony collapse disorder (CCD) has recently caused a significant decline in honeybee numbers worldwide. The beekeeping industry, agriculture, and world biodiversity are threatened by the honeybee population decline. We examined the mRNA levels of heat shock protein gene 60 (hsp60), acetylcholinesterase 1, and acetylcholinesterase 2, as biomolecular markers of the insect response to three separate forms of environmental stress, including high temperature, low temperature, and insecticide. The obtained results indicated increased levels of hsp60 and acetylcholinesterase 2 after the exposure of worker bees to temperatures of 17, 32, and 40°C for one hour, as well as exposure to a low dose of pesticide for 24 h ingestion of imidacloprid solution (2 ppm); meanwhile, acetylcholinesterase 1 showed remarkable expression decrease under heat and cold stresses but increased under pesticide treatment. The responses of honeybees to hsp60, acetylcholinesterase 1, and acetylcholinesterase 2 are diverse and very specific to various stimuli. According to this research, the distinct expression profiles of hsp60 and acetylcholinesterase 2 can serve as useful instruments for tracking honeybees' vulnerability to varied environmental effects. Due to its insufficient responsiveness, acetylcholinesterase 1 expression is not permitted for use as a biomarker.
Показать больше [+] Меньше [-]Evaluation of Certain Synthetic and Natural Pesticides Against Whitefly Bemisia tabaci (Genn.) on Green Bean and Effect on Honeybee Apis mellifera L.
2023
Ahmad, Sharihan | Abdelghany, Walaa | Ahmed, Ahmed | Abdelmegeed, Sawsan
The green bean crop (Phaseolus vulgaris) is infested with many insects such as whiteflies (Bemisia tabaci). An investigation was carried out to study the insecticidal activity of whitefly (Bemisia tabaci), five pesticides were used, namely Thiamothoxam, Sulfoxaflor, Spirotetramat, Pymetrozine, and Flonicamid, and three commercial natural pesticides, namely Superrego, Topnine, and Bernastar. Pesticides and natural pesticides were sprayed during the two seasons of 2020 and 2021. The obtained results in terms of the reduction rate of the insects' number were as follows: The highest rate of reduction appeared in Thiamothoxam and Sulfoxaflor treatments, where it reached above 80%, while the other pesticides were in the range of 40% to 60%, and the lowest reduction rate was 34.33% and 36.00 % for Bernastar during season 2020 and 2021 respectively. When evaluating the toxicity of these pesticides and natural pesticides against honeybees (Apis mellifera), the pesticides did not reveal any toxicity to honeybees, except for Thiamothoxam, Sulfoxaflor, and Superrego The LC50 and LD50 values against honeybees were 0.2 ppm and 0.000005µg/one honeybee for Thiamothoxam, 4.5 ppm and 0.0001125 µg/one bee for Sulfoxaflor, and 0.95 ppm and 0.00002375 µg /one bee for Superego respectively.
Показать больше [+] Меньше [-]Inhibition of Rhizoctonia solani Growth and Its Extracellular Hydrolytic Enzymes by Different Extracts of Cinnamon (Cinnamomum cassia) and Black Cumin Seeds (Nigella sativa)
2022
Abd El Aziz, Seham | Abo-shady, Ahmed | Ibrahim, Mervat | Helmy, Maha
The present study evaluated the ability of different extracts of cinnamon and black cumin seeds to inhibit the growth of the phytopathogenic fungus Rhizoctonia solani and its extracellular cell wall degrading enzymes. Concentrations of 300 and 450 ppm of methylene chloride and hexane extracts of cinnamon completely inhibited the growth of R. solani after 72 hours of incubation at 25±1°C in vitro. Methylene chloride or hexane extracts of black cumin seeds at 4000 ppm after 72 hours inhibited the growth of R. solani by 37 and 39% respectively. Moreover, black cumin seed hexane extract at 2000 ppm inhibited 55% and 38% of the activity of pectin lyase (PL) and polygalacturonase (PG) respectively. In addition, the methanolic extract of black cumin seeds at 2000 ppm exhibited a significant reduction of exo-protease activity (74.8%). GC-MS analysis results showed that linoleic acid is the main component of the fixed oil fraction of black cumin seed hexane extract while (E) cinnamaldehyde is the main component in both hexane and methylene chloride extracts of cinnamon. HPLC-MS analysis of black cumin seeds methanolic extract showed that amentoflavone was the main component. Docking was used to identify the major component interaction with pectin lyase A and exo-protease.
Показать больше [+] Меньше [-]Improvement of Growth and Productivity of Mango Trees Using Some Growth Stimulants under Salinity Conditions
2022
Abdalla, Fatma | Elwakeel, Hassan | Mansour, Noha | Osman, Sabry
A study was carried out in a mango orchard on reclaimed land for two seasons in 2019 and 2020. The experiment was implemented on fifteen years old mango trees “Fagri Kalan” budded on seedling mango rootstock and planted at 4 × 4 m. This experiment involved two soil growth stimulants (K humate, magnetite) and foliar application with cobalt. The experiment involved two factors, the first one was soil application with K humate by two levels (50 and 100 g/tree/year) and magnetite by two levels (250 and 500 g/tree /year) plus control, whereas the second factor was a foliar application with Co as cobalt sulfate by three levels (0, 15, and 30 ppm Co). The experiment was carried out in a factorial experiment in split plot design with three replicates whereas each replicate was represented by two trees. Result indicated that soil application with K humate at 100 g/tree followed by magnetite at 250 g/tree or foliar application with Co at 15 ppm alone or the combination between (K humate at 100 g/tree and cobalt at 15 ppm) gave the highest values of yield/tree, fruit weight, TSS, reducing sugars, leaf N, P, K, and Fe content of “Fagri Kalan” mango trees grown under salinity conditions.
Показать больше [+] Меньше [-]Impact of Maltodextrin and Inulin on Synbiotic Fermented Milk Production
2022
El-Komaily, Reda Mohamed | Elbatawy, Osama | Aumara, Ihab
The influence of maltodextrin or inulin added as a prebiotic on the survival of various strains of probiotics in synbiotic fermented milk along cold storage was investigated. Synbiotic fermented milk was prepared using several probiotic strains (Lb. helveticus and Lb. acidophilus) and 2% maltodextrin or inulin and compared with traditional yoghurt starters (Lb. delbrueckii subsp. bulgaricus and Str. thermophilus). Synbiotic fermented milk samples were stocked at 4°C then the chemical, microbiological and sensory characteristics were estimated. Starter culture strains showed no significant effect on dry matter and ash contents in various synbiotic fermented milk samples during storage. However, starter culture type, fortification by maltodextrin or inulin, and storage period significantly influenced the acidity, total and soluble nitrogen contents (SN\TN), acetaldehyde, diacetyl contents and viscosity in various synbiotic fermented milk samples. In addition, fortification of maltodextrin or inulin significantly influenced the survival of yoghurt starter culture strains, Lb. helveticus and Lb. acidophilus strains. The counts of probiotic strains used in all treatments of synbiotic fermented milk survived well and were above the recommended minimum levels (106CFU/ mL) during a storage period.
Показать больше [+] Меньше [-]Effect of Different Levels of Salinity and Anti-Transpiration on the Growth Characteristics and Chemical Composition of Panicum maximum (Jacq.)
2022
El Wardany, Adel | Elbordiny, Nasr | Abdrabou, Ramadan | Bakr, Adel | Abdelkareem, Yasser
This study aimed to determine the effect of different salinity and anti-transpiration levels on the growth and biochemical composition of Panicum maximum plants (Guinea grass) during the spring and summer of 2020. Two different anti-transpiration treatments [molasses (sugarcane) (5 mL/L), kaolin (50 g/L) and control] and three salinity levels (S1 well water as the control and salinity S2 2000 ppm; S3 4000 ppm, S4 6000 ppm) were used in 12 treatments in 72 pots (3 anti-transpiration treatments × 4 salinity treatments × 6 replicates); a randomized complete design was used. Results revealed that the plants achieved the highest plant height (123.77 cm) and dry weight (521.87 g/m2) with kaolin and no salt addition treatment during summer. A higher percentage of proteins and carbohydrates were found in spring than in summer, but there was no significant difference in the salinity levels. A high percentage of ash and fiber contents was also observed during summer, with no significant differences between the anti-transpiration treatments. It could be concluded that P. maximum, as one of the most important fodder crops, could be cultivated in marginal lands, especially during the summer season.
Показать больше [+] Меньше [-]Performance and Stability of Promising Bread Wheat Lines for Grain Yield and Yield Components
2022
Badr, Asmaa | Saleh, Samir | Mohamed, Amal | El-Gabry, Yasser
The present study was conducted to evaluate 50 wheat genotypes for their productivity and stability under eight environmental conditions. Wheat genotypes were sown at two planting dates under two nitrogen fertilization treatments during the winter seasons of 2018/2019 and 2019/202. The analysis of variance showed that the mean squares of genotypes, sowing dates, and nitrogen fertilization treatments were significant for the number of spikes/plants, the number of kernels/spikes, 1000-kernel weight, and grain yield/plant. The results showed that sowing at the favorable date using 80 kg N/fed increased all studied traits. This study revealed that line numbers 9 and 10 exhibited general adaptability across different environments; hence, these lines are considered promising and could be exploited in breeding programs for wheat improvement.
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