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Результаты 31-40 из 1,443
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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]Molecular Identification of Some Rhizobium and Serratia Isolates as Potential Producers of Indole-3-Acetic Acid
2023
Sello, Shaimaa | Abdel Razik, Ashraf | Ibrahim, Samir | Elateek, Sawsan
In order to reduce the use of chemical fertilizers, the use of biological inoculants has been increased. Beneficial microorganisms are used to increase crop yields by stimulating plant growth through the production of phytohormones. In the present study, Indole Acetic Acid (IAA) production was analyzed in 18 bacterial isolates with Plant Growth-Promoting (PGP) capabilities; 15 of these isolates were Rhizobium, and three were Serratia. All isolates have been characterized morphologically and biochemically, and their IAA production in the presence of tryptophan, a precursor for IAA biosynthesis, has been evaluated. IAA production was detected using the Salkowski reagent with CT-2200 spectrophotometer at 530 nm. The levels of IAA production varied between the different isolates. The top two IAA producers were selected for genetic identification using 16SrRNA primers (27F and 1492R). One of the Rhizobium isolates (NRC-R2) shared 95% sequence similarity with Rhizobium sp., according to a Blastn search in GenBank and Rhizobium leguminosarum, whereas the Serratia isolate (Ain Shams Center for Genetic Engineering and Biotechnology (ACGEB)-S2 was 99.5% similar to Serratia sp. In the near future, it is possible that these two isolates could serve as biological sources for IAA.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]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.
Показать больше [+] Меньше [-]Partial Gap-Filling of the Nile Tilapia Oreochromis niloticus Draft Genome
2023
Zoghly, Hala | Rashed, Mohamed | Magdy, Mahmoud
Nile tilapia is a freshwater fish of African origin, with productive and economical characteristics affecting global fish markets. The Oreochromis niloticus reference genome has a diploid set of 22 linkage groups (LGs) in addition to ungrouped sequences. A total of 42,622 genes have been identified, but 550 genomic gaps may include more. Our study focused on some of these genomic gaps, where appropriate primers were designed and then multiplied through the polymerase chain reaction (PCR) technique. From local samples, DNA was extracted and amplified with the new primers. Successful amplicons were sequenced and annotated using available bioinformatics tools. Five assessed sequences were annotated, of which three were newly predicted in O. niloticus, as mucin 1-like, and KLR genes, and SATB region. The other two sequences belonged to grid2 and trpm7 which were previously predicted. Although individual attempts to identify genomic gaps are not feasible in filling the large lack of information on the Nile tilapia genome, a good number and valuable new information has been reached. How-ever, the following plan showed many technical problems, more time, effort, and cost that could be avoided by suggesting the application of another technique, such as whole-genome sequencing, mapping, and assembly.
Показать больше [+] Меньше [-]Increasing of Amylopectin in Tetraploid Potato Desiree Cultivar (Solanum tuberosum L.) Via CRISPR/Cas9
2023
Ali, Nermin | Abdel-Salam, Mohamed | hanfy, aiman | Abd-Elhalim, Haytham | Ahmed, Nouh | Metry, Emad
Potato tuber starch characteristic is influenced by the ratio of amylose to amylopectin, which is affected by the granule-bound starch synthase (GBSS) gene. GBSS gene expression was decreased in the leaves of the Desiree potato variety utilizing genome editing using CRISPR-Cas9. Constructs encoding Cas9 gene and sgRNAs targeting GBSS gene were inserted into plant leaves using Agrobacterium-mediated transformation delivery. The results obtained lines with mutations in GBSS genes accounting for 21% of regenerated shoots. The identification of mutations within one base pair of the used guide sequence provided further evidence of the considerable similarity between the target region around the protospacer adjacent motif (PAM) position and the used guide sequence. Transforming DNA into potato leaves produced mutants that lacked the Cas9 gene. Using microscopic inspection of iodine-stained starch granules, the increase of amylopectin in the starch granules of editing potato tubers was evaluated.
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