Refine search
Results 31-40 of 60
Seasonal Effects on Some Eco-Morphological and Physiological Characters of Tamarix nilotica (Ehrenb) Bunge Growing Naturally in Egyptian Northern Coastal Salt Marshes
2022
Aya Mehanny | Gamal Khalifa | Ola Abd Elbar | Sami Habib | Maryam Abba Dawud
Tamarix nilotica is a perennial halophyte growing naturally at the Mediterranean coastal salt marshes. Vegetative parts were collected in two successive winters and summers to investigate the seasonal effects on the ecomorphological and physiological responses of T. nilotica. The results indicated that either in winter or summer seasons, T. nilotica can reduce the effect of soil salinity by excreting salts outside its body through salt glands. Summer season was characterized by low content of soil moisture (due to rare rainfall), high soil EC, high light intensity and high temperature; there-fore, plant induced certain morphoanatomical changes in leaves and stem to face the previously mentioned adverse conditions. The most remarkable changes to reduce transpiration process was found by decreasing leaf area and increasing cuticle thickness and mesophyll tissue thickness. In addition, the most marked physiological changes in summer were the significant in-crease in total phenols, proline, free amino acids and total soluble sugars. These compounds can work as osmotic regulators and/or antioxidants. These features enhance the defensive mechanism against dehydration and permit T. nilotica to tolerate the stress conditions in salt marsh habitat.
Show more [+] Less [-]Impact of Maltodextrin and Inulin on Synbiotic Fermented Milk Production
2022
Reda Mohamed El-Komaily | Osama Elbatawy | Ihab Aumara
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.
Show more [+] Less [-]Evaluation of Some Essential Oils Against Wax Moth Larvae (Lepedoptera: Galleria mellonlla L.) and Adult Honeybee Workers (Hymenoptera: Apismellifera L)
2022
Ekbal Helaly | Mahmoud A Ali | Naglaa Ghazala
This study was conducted to investigate the effects of five essential oils (garlic, Allium sativum; camphor, Cinnamomum camphor; menthol, Mentha sp.; cinnamon, Cinnamomum erum; and clove, Dianthus sp.) on wax moth larvae and adult honeybee workers under laboratory conditions. Cinnamon, garlic, menthol, clove, and camphor oils were found to be highly effective against wax moth larvae, with 100 percent mortality achieved after 48 and 96 hours for cinnamon and garlic oils respectively, and after 120 hours for clove and mint oils. Camphor oil provided 96.60% accumulative mortality after 120 hrs. Moreover, all the essential oils were highly safe for adult honeybee workers under laboratory conditions. Accumulative corrected mortality rates after 72 hr were 15.96, 9.02, 13.18, 29.16, and 8.88% for treatments with cinnamon, clove, camphor, mint, and garlic oils respectively.
Show more [+] Less [-]Inhibition of Rhizoctonia solani Growth and Its Extracellular Hydrolytic Enzymes by Different Extracts of Cinnamon (Cinnamomum cassia) and Black Cumin Seeds (Nigella sativa)
2022
Seham Abd El Aziz | Ahmed Abo-shady | Mervat Ibrahim | Maha Helmy
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.
Show more [+] Less [-]Evaluation of the Efficiency Different Types of Bee Pollen-Collection Traps in Honey Bee Colonies during Summer Season
2022
Eman Mohamed | Mahmoud A Ali | Naglaa Ghazala
The efficiency of three different types of pollen-collection traps namely, Front Drawer Pollen Traps (Type, 1), Bottom Pollen Traps (Type,2) and Plastic Slide Traps (Type,3) were evaluated. The data indicated that in type 2, which had Bottom Pollen Traps, a significantly high amount of bee pollen was collected (383.30g/colony) followed by type 1, (179.37g/colony) while type 3 had the lowest amount of collected bee pollen (123.80 g/colony). The highest amount of bee pollen collected during summer was from type (2) during 20 -29 July, followed by that from the same group during the periods 1-10 July and 9-18 August, and then type (1) during the peri-od 20-29 July. The results also revealed that the lowest amount of bee pollen collected by the traps was during the last week of August and September.
Show more [+] Less [-]Effect of Variable Frequency Drive and Pipe Materials on Guava Juice Flow
2022
Shereen Shalaby | Mubarak Mustafa | Yahiya Heikal | Mahmoud El Attar
In this study, a designed variable frequency drive (VFD) was used to control a single-phase induction motor’s speed to pump guava juice at two solid concentrations (9°Bx and 11°Bx). Next, the pressure drop was measured in stainless-steel pipes of three diameters. The pressure drop percentage difference before and after using the VFD at varied flow rates with 10 repetitions at 5-minute intervals was evaluated. The pressure drop reduction range was 19.7%– 30.8% and 19.2 %–32.4% for the 9% and 11% solid concentrations respectively after using the VFD, which resulted in an average of 25.73% reductions in pressure drop and the pump’s total head and driving power. The rheological properties of guava juice were investigated at various temperatures (5, 15, 25, 35, 55 and 75°C). From the results, all materials exhibited non-Newtonian pseudoplastic behavior at all temperatures and concentrations, and correlated well with the power law model, with flow behavior index (n) values less than unity for the 9% and 11% solid concentrations. The findings offer helpful information for predicting how heat variations during processing influence the behavior of guava juice concentrates.
Show more [+] Less [-]Productivity Improvement of Canola Genotypes Under Salinity Stress Conditions by Integration between Mineral and Nano-Scale forms of Nitrogen Fertilizer
2022
Doaa Mohamed | Mohamed Fergany | Elsayed Elhabbasha | Mohamed El-temsah
Two field experiments were conducted during in 2019/20 and 2020/21 seasons to study the impact of integration among mineral and nanoparticle nitrogen (N) fertilizer levels on yield traits and chemical characters of some canola genotypes grown under salt stress conditions. Four treatments of N fertilization (190 kg N/ha as recommended dose; 50% of the recommended, 95 kg N/ha+nano nitrogen (5 L/ha); 25 % of the recommended, 47.5 kg N/ha+nano-nitrogen (5 L/ha), and nano-nitrogen (rate of 5 L/ha). canola genotypes (Trabber, Agamax, and Serw4) performance were assessed under three levels of saline irrigation water (control, 2000, and 4000 mg L-1). Results showed that increasing salinity levels up to 4000 mg L-1 led to decreasing in all studied yield parameters compared with those of control (tap water). Trabber genotype excelled significantly in most of the yield characteristics. Integration between nanoscale and mineral nitrogen fertilizer, i.e. 95 kg N/ha+5 nano N L/ha) showed superiority over all applied N treatments, recording the highest values. It could be concluded that since application of 95 kg N/ha+5 nano N L/ha exploiting the nano form of N saves about 50% of applied nitrogen in canola under saline conditions. Accordingly, nanoparticles help the environmental pollution to be reduced.
Show more [+] Less [-]Evaluation of a Solar Water Distiller Coupled with Solar Evacuated Tubes
2022
Israa Eldehn | Mubarak Mustafa | Mohamed Atia | Mohamed Salama | Yehia Galal | Mohamed Hussein
The scarcity of fresh water is a primary problem in remote regions. Thus, an economical and related water distillation solar still coupled with a solar collector was designed and studied experimentally. This study aims to investigate and evaluate the performance of an active single-slope solar still (ASSSS) coupled with a solar evacuated tube collector (ETC) as the water heater. The results showed that the average distillate productivity of ASSSS combined with U pipe solar (ETC) was 1.085 l/m2 in December 2020, but 3.12 l/m2 in August 2021. These quantities of the water distiller were higher than those of a passive solar distiller with a single slope (PSSSS). The average value of the water temperature increased using the ASSSS coupled with ETC in August 2021 at 79.1°C, whereas it was 71°C in August 2021 for PSSSS. These results indicate that the ASSSS is more effective than the PSSSS.
Show more [+] Less [-]Effect of Different Nitrogen Rates on Gray Water and Water Footprint to Potato
2022
Mai Abd Elsalam | ahmed Farag | mohamed El-Shinawy | Ayman Abou-Hadid
The importance of water footprint (WFP) is providing information related to water resource management, especially for countries that have water scarcity and rely on irrigation to enhance food security. A field experiment was conducted during two winter seasons in 2018, and 2019. The current study sought to evaluate the impacts of various nitrogen levels (1.N1: 120, 2.N2: 150, and 3.N3: 180 kg /fed) on potato production as well as the water footprint and water requirement. Vegetative characteristics, yield parameters, N contents, and climate data were measured. The obtained results are clarified that increasing the nitrogen rate up to 180 kg/fed led to increase the vegetative growth characteristics, yield parameters, and water footprint of potato crop. The most significant vegetative growth values were obtained using a 180 kg/fed nitrogen level followed by 150 kg/fed. The greater marketable tuber yield was recorded at 180 kg/fed with 18117 & 17753 Kg/fed values, followed by 150 kg/fed with 16864 and 16545 Kg/fed values for the first and second seasons respectively. The water footprint of potato in Egypt ranges from 237 to 267.8 for nitrogen levels of 120 kg /fed and 180 kg /fed.
Show more [+] Less [-]Element Composition and Toxicity of Seaweed Algae (Ulva lactuca, Laurencia obtuse and Padina pavonica) Toward Shrimp
2022
Ahmed Muhammad | Ibrahim Hassan | Manar Tawfeek | Hayam Ahmed Ibrahim
This study examined the macro and trace element contents as well as the cytotoxicity of Laurencia obtusa, Ulva lactuca, and Padina pavonica algae collected from the Mediterranean coast of Egypt (Alexandria coast). The results indicated that the seaweed samples contained high concentrations of Ca, Cl, Mg, K, Na, P and Fe. The Cu and Zn contents of the algae were in the ranges of 0.39-0.95 mg/100 g dw and 0.11-0.49 mg/100 g dw respectively. Fresh red algae contained the highest level of Zn and Cu, whereas the iodine level was 1.52, 1.27 and 1.01 mg/100g in fresh each of Padina pavonica, Laurencia obtuse and Ulva lactuca respectively. Fresh red, fresh green, dry green, dry red, in addition to fresh and dried brown algae had maximum lead (Pb) levels of 0.16, 0.14, 0.13, 0.12, 0.04 and 0.02 g/100 g respectively. Fresh red algae contained the highest Cd and Mn levels, whereas dried brown algae exhibited the lowest Cd and Mn concentrations. Different extracts of fresh and dried brown algae exhibited significant larvicidal activity against brine shrimp. LC50 values indicated that dry samples were more cytotoxic than fresh samples.
Show more [+] Less [-]