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Phytochemical, Antioxidant and Antibacterial Activities of Golden berry (Physalis Peruviana L.) Extract and its Effects on the Storage Stability of Tomato Paste
2022
Anwar, Dina | Eed, Heba | El-Chaghaby, Ghadir A | Farid, Ahmed
This study focused on the phytochemical, antioxidant, and antimicrobial activities of the ethanol extracts of golden berry calyx and fruits. The phytochemical analysis of calyx and fruit extracts revealed high total phenols and flavonoids. High antioxidant capacity was recorded for fruit extracts. Fruit extracts also gave the highest antibacterial activity against Pseudomonas fluorescens, Escherichia coli, and Salmonella typhimurium. Furthermore, tomato paste was prepared using sodium benzoate and golden berry extract as food preservatives. The incorporation of golden berry extract and chemical preservatives maintained the paste quality indicators over the control samples. A rapid decline in total antioxidant capacity was also observed in control samples (21.6%) as compared with the treated samples (15.21% and 15.41% for sodium benzoate and golden berry extract, respectively) after 30 days of storage. This study demonstrated that dried fruit extract with high phytochemical and antimicrobial properties could be used as a natural food preservative.
Afficher plus [+] Moins [-]Evaluation of Orius laevigatus as a predator of Bemisia tabaci In Vitro
2022
Salama, Nada | Emam, Azza | washahy, Kadry | Gaffar, Saad
This study determined the ability of Orius laevigatus to consume different stages of Bemisia tabaci at various densities. Additionally, the use of B. tabaci as food and its effect on the life cycle parameters and female fecundity of Orius predator developmental stages were investigated. The results showed that O. laevigatus could consume whitefly at various stages and complete its preimaginal and postimaginal stages, with B. tabaci eggs, nymph instars, and adults as the only available food source. The consumption and fecundity of O. laevigatus were influenced by feeding on different stages of B. tabaci. Furthermore, the females of this predator consumed more eggs, fourth nymphal instar, and adults than the first, second, and third instar nymphs of B. tabaci on a different density level. The mean numbers of consumptions at different stages of B. tabaci increased with increasing prey densities. The result simply that O. laevigatus can be used as a predator in the biological control of tobacco whiteflies.
Afficher plus [+] Moins [-]AquaCrop Model Enhancement under Soil Mulching Practices Considering Soil Temperature Effect
2022
Mahmoud, Sobhy | Arafa, Yasser | abdel aziz, Ahmed Abo El-Hassan | El-Gindy, Abdel-Ghany
Soil temperature under mulching conditions has a significant impact on crop development, growth rate and other parameters. However, it is not included in the AquaCrop model. Thus, this study aims to improve the AquaCrop model performance for better simulation of soil mulches by considering the heat changing under mulch materials. The proposed modification is conducted through AquaCrop-Open Source software to identify the differences between the temperatures under the mulched soil and air temperatures. It will also help to describe them as additional heat units in specific growth stages. The field data used to evaluate the proposed model has previously been used to calibrate and validate the AquaCrop model in simulating melon growth under different irrigation treatments and soil mulching practices. The results show that the proposed model performs better than the original model in simulating mulched melon under different irrigation regimes. The root mean square error of biomass values was reduced under the modified model by 40%-75% under different irrigation treatments. Additionally, the coefficient of determination (R2) of the modified model slightly increased from the original one. Thus, the proposed model provides a more reliable and robust model.
Afficher plus [+] Moins [-]Steroidal Saponins as Antioxidant and Alleviator of CCl4-Induced Oxidative Damage in Albino Rats
2022
Eliwa, Hala | Ibrahim, Mervat | EL-Sayed, Salwa | Abdelhamid, Mohamed
Liver toxicity is a common condition that can be induced by environmental pollutants. The present study explored the hepatoprotective activity of steroidal saponins extracted from the yam plant versus CC14-induced hepatotoxicity in albino rats. Twenty-five albino rats were classified into 5 groups. Rats of group (G1) were provided a basal diet and drinking water and served as un-treated controls. Other groups were administered CC14 orally twice a week at a dose of 400 mg/kg. The second group (G2) did not receive any further treatment and served as positive controls while rats in the groups G3, G4 and G5 were administered saponins (50,100 and 200 mg/kg body weight, respectively) for six weeks in the remaining groups. The hepatoprotective activity of saponins was assessed by measurement of liver enzymes, kidney function tests, malondialdehyde content, and antioxidant defense enzymes activities in serum of these rats. Saponins administration improved liver and renal function and significantly increased the activities of catalase, glutathione peroxidase (GSH-PX), glutathione reductase GSH-RD and superoxide dismutase SOD. These increases were linked to a considerable decrease in serum malondialdehyde levels, indicating that lipid peroxidation was being mitigated. Thus, the concentration of saponins (200 mg/kg) is the best concentration of protection against CC14-induced hepatic injury, improved liver and renal function, and reduced oxidative stress in rats.
Afficher plus [+] Moins [-]Productivity Improvement of Canola Genotypes Under Salinity Stress Conditions by Integration between Mineral and Nano-Scale forms of Nitrogen Fertilizer
2022
Mohamed, Doaa | Fergany, Mohamed | Elhabbasha, Elsayed | El-temsah, Mohamed
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.
Afficher plus [+] Moins [-]DNA Barcoding for Some Medicinal Plants in the El-Omayed Biosphere Reserve
2022
Nabil, Reham | Rashed, Mohamed | Elmosallamy, Mahmoud | Elsherbeny, Esraa
DNA barcoding is a valuable tool for molecular identification of plant materials, which is primarily employed to guarantee the nature and therapeutic value of all available medicinal plants. Identification is crucial for the illegal medicinal plant trade, safe use, and preventing adulteration. In this study, DNA barcoding was used to evaluate and confirm the identification of some medicinal plants from the El-Omayed Biosphere Reserve (OBR). Two DNA regions, rbcL and ITS were selected due to their universality, ease of amplification and sequencing, and ability to identify taxa at the generic and species levels. The ITS region demonstrated a higher capacity for species discrimination power than the rbcL region. It assisted in identifying four of eight plants more precisely than rbcL. Together, ITS and rbcL could be used for plant species identification, conservation, and trade control of valuable plant resources.
Afficher plus [+] Moins [-]Evaluation of Biologically Treated Olive Mill Wastewater for Irrigation of Pea Plant
2023
Abdelhafez, Ahmed | yehia, Rokia | Abdelaal, Azza
This study evaluated the use of biologically treated olive mill wastewater (OMWW) for irrigation of pea plants, rather than discharging this nutrient-rich liquid and polluting the environment. Pea seeds were planted in pots containing soil irrigated with tap water (control), untreated (crude) OMWW, or OMWW treated with the fungus, Pleurotus columbinus, or algae Spirulina platensis or Wollea sp., with two NPK rates. Plant length shoot and root dry weight, nitrogen, phosphorus, potassium, chlorophyll, and carotene contents were measured, along with to nitrogenase and dehydrogenase activity. The highest shoots N and P content were recorded in plants irrigated with Sp. Platensis-treated OMWW + 100% NPK; while the highest K content was in plants irrigated with crude OMWW + 100% NPK. The highest dehydrogenase activity, 59.01 μg TPF/100 g soils, was recorded in plants irrigated with P. columbinus-treated OMWW supported with 75% NPK, while maximum nitrogenase activity (261.82 μmol/100g soil/day) occurred in plants irrigated with Wollea sp.-treated OMWW with 75% NPK. The highest content of chlorophylls a & b and carotene (0.838, 0.276, 0.252 mg/g dry weight, respectively) were found in plants irrigated with OMWW treated with Wollea sp. and 100% NPK. Thus, biologically treated OMWW showed promising impacts on plant growth parameters.
Afficher plus [+] Moins [-]Residue Assessment of Bifenazate, Spirodiclofen and Abamectin in Strawberry Fruits Under Field Conditions
2023
Abdelmaksoud, Eman | Elsayed, Walaa | Elrefai, Shoukry | mahmoud, kadry
The dissipation behavior of three pesticides, bifenazate, spirodiclofen and abamectin was studied in strawberry fruits using a modified QuEChERS extraction technique. The residues of the tested acaricides were determined under field conditions after 1 hour (zero days), 1, 3, 7, 14, and 21 days. The maximum residue limits (MRLs) were 2, 2, and 0.15 mg/kg for bifenazate, spirodiclofen and abamectin, respectively. The strawberry fruits could be used safely after 15 days from bifenazate spraying and after 3 days from spirodiclofen spraying. The concentration of abamectin after 21 days did not reach MRL. The half-life values (t1/2) of bifenazate, spirodiclofen, and abamectin in strawberry fruits were 0.99, 0.86, and 5.7 days, respectively.
Afficher plus [+] Moins [-]Production of Functional Ice Cream Using Camel Milk Fat Fractions
2023
Abutaha, Alaa | Hussein, Gehan | Desouky, Marwa | Awad, Rezk
The aim of this work is to examine the quality features of functional camel ice cream (8% fat) prepared by replacing the cream with a solid milk fat fraction (SMF), a liquid milk fat fraction (LMF) and LMF:SMF (2:1 v/v) in the ice cream mixtures. All samples were assessed for their physio-chemical and rheological characteristics and the sensory quality of the ice cream mixtures and resulting ice cream. The results clarified that the type of milk fat fraction affected the viscosity of the ice cream mixtures. Also, the whipping ability decreased gradually with increasing slip melting point of the fraction used. The use of SMF in the ice cream mix decreased the adsorption of protein and fat destabilization, characterized by the slowest melting compared to ice cream with other milk fat sources. The highest and lowest hardness values were found in ice cream mixtures made with SMF and LMF, respectively. In conclusion, ice cream was successfully made by replacing the milk cream fat fractions. Cream substitution with SMF followed by LMF:SMF (2:1 v/v) is recommended in arid and semi-arid regions and improved the whipping ability, overrun, and flavor scores, which were lower when using SMF.
Afficher plus [+] Moins [-]Stenotrophomonas rhizophila a Novel Plant-Associated Bacterium With Distinguished PGPRs Properties
2023
Elhosieny, Asmaa | Zayed, Mona | Selim, Shawky | Abdel Aziz, Norhan
Stenotrophomonas sp. is a plant-associated rhizospheric bacteria. It has the capability to enhance plant productivity. It acts as a mineral dissolution and growth promoter for plants under salt-stress conditions. The selected isolates revealed the general morphological and biochemical characteristics of Stenotrophomonas sp. All the isolates exhibited the highest growth density after 15 hr. at 30˚C, resistance to different levels of salinity, different pH levels, and different temperature degrees. Also, the isolates revealed their capabilities to solubilize phosphorus and potassium and to pro-duce different phytohormones. The isolate X.M9 exhibited the highest growth performance in the form of 1.376,1.326,1.292,1.053 and 1.059 OD in most salts’ concentrations compared to all tested isolates respectively. As well it (X.M9) exhibited the highest resistance to low temperatures 10 and 15oC being 0.917 and 1.354 OD respectively. The isolate X.M9 recorded the highest IAA of 83.73 mg/100ml compared to all the tested isolates. The isolate X.M9 were identified using 16 SRNA sequencing and submitted to the GenBank database under accession number No: OP050187 as Stenotrophomonas rhizophila.
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