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Physico-Chemical Properties, Fractionation and Antioxidant Activity of Some Essential Oils Utilized in Mayonnaise Preparation and Storage
2021
Mamdouh El kalyoubi | Mohamed Khalaf | Abdel-Aziz Shehata | Wafaa Abozeid | Mohamed Mansour
Two types of essential oils (thyme and Stachys) were used in this Estimation. The chemical composition, antioxidant activity (by DPPH assay) and the rancimat method were used to assess the stability effect of these essential oils. The tested oils were added to mayonnaise to evaluate its capability for inhibition of secondary oxidation products. By DPPH assay, antioxidant activity showed that thyme essential oil was the best antioxidant agent as radical scavenging agents at 450 and 500 ppm concentrations, even better than BHT at the200 ppm concentration. As a typical antioxidant, butylated hydroxytoluene was used for comparison. The mayonnaise samples prepared by adding thyme, stachys essential oils and TBHQ (control +) at concentrations of 200,400, 600 and 200 ppm into the sunflower oil free from antioxidant. At the amounts used in this study, thyme and stachys oils were significantly successful in reducing the oxidation of sunflower oil, especially, at 500 ppmwhich showed more efficient than BHT. Specifically, in the presence of thyme oil, the induction period of sunflower oil was considerably elongated. However, butylated hydroxytoluene (BHT) was more efficient than thyme and Stachys oils at the 200-ppm concentration against oxidation of oils. all concentrations of thyme and stachys essential oils had an antioxidant activity similar to synthetic antioxidant of TBHQ at a concentration of 200 ppm for inhibition of secondary oxidation products in mayonnaise in comparison with the control sample. As a conveniently available source of natural antioxidants, thyme and stachys essential oils can be used for use in fats, oils and food containing fats.
Afficher plus [+] Moins [-]Using Probiotic Bacteria for Soymilk Fermentation
2021
Abdallah Gad | Mona Orabi | Dina Abdelghani | Khadiga Aboutaleb | Shimaa amin
Five probiotic bacterial strains (Lactobacillus plantarumATCC 14917,Lactobacillus caseiDSM 20011, Lactobacillus acidophilus ATCC20552, Lactococcus thermophilus DSM 20259,and Bifidobacterium longum B41409) were used as monoculture, and combined with them as co-cultures for the fermentation of soymilk. The total number is 20 co-cultures, separated similarly into two parts, the first half of each co-culture consisted of two strains, and the second half of each co-culture consists of three strains. The findings revealed that these cultures were capable of fermenting soymilk at only 8 h with a pH drop of between 4.42 and 4.89. Among 25 cultures, eight cultures (3 monoculture of L. plantarumATCC 14917 (C1),Lc. thermophilusDSM 20259 (C4), and B. longum B41409 (C5) and co-cultures of two strains L. plantarum ATCC 14917+ Lc. thermophiles DSM 20259 (C8) and of three strains L. plantarum ATCC 14917 + Lc. thermophilus DSM 20259 + B. longum B41409 (C18), L. plantarum ATCC 14917+ L. caseiDSM 20011+ Lc. thermophilus DSM 20259 (C19), L. caseiDSM 20011+ L. acidophilus ATCC20552+ Lc. thermophilus DSM 20259 (C22), and L. acidophilus ATCC20552+ Lc. thermophilus DSM 20259 + B. longum B41409 (C25)) which recorded the greatest significant viability of bacterial cells, titratable acidity, total organic acids (lactic, acetic, and propionic acids) contented, and pH in fermented soymilk ranged from 9.26 to 9.98 Log CFU/mL, 3.06 to 3.32 %, 19.90 to 18.40 g/L (lactic acid), 13.30 to 12.30 g/L (acetic acid), and 16.35 to15.00 g/L (propionic acid), and 4.38 to 4.62. The soy yogurt produced from the selected fermentation of soymilk was more preferred in the chemical composition of protein, carbohydrate, and fat contents than non-fermented soymilk.So the results show that the integrative use of probiotics may achieve the nutritional value of soymilk after fermentation had been improved by probiotic strains, therefore, making it a more health-beneficial functional food.
Afficher plus [+] Moins [-]Effect of Fungicide, Salicylic Acid, Henna Powder and Propolis on Silkworm Larvae Infected with Aspergillus spp.
2021
Eman Abd El-Razek | Madiha A Rizk Rizk | Youssef Abdallah | Khadiga Abou-Taleb | sawsan abdelmegeed
Mulberry silkworm, Bombyx mori L. is in-fected with many diseases. In this work, two fungi species, Aspergillus fumigatus and As-pergillus flavus, were isolated from the in-fected B. mori larvae during rearing process. The morphological symptoms were the same for both fungi and appeared from newly hatched larvae until moth formation. In larvae, black spots of both fungi species appeared eve-rywhere on the body, then these spots extended and eventually larvae died, and fragments of the fungus came out from the spots. The only one difference between the two fungi, is that symptoms of A. fumigatus appeared four days earlier than those of A. flavus. Newly hatched larvae were sprayed with spore suspension (1x106 conidia spores/ml) of A. fumigates and A. flavus separately. One and 12 hrs. after in-oculation, larvae were sprayed with different concentrations of fungicide (Actamyl), sali-cylic acid, and henna and propolis powders, in isolation. After words, mortality and survival percentages were calculated and compared to those that occurred in untreated check (larvae were inoculated with A. fumigatus and A. fla-vus separately without any control treatment). The lowest mortality and highest survival per-centage were occurred in larvae treated with salicylic acid at 10% after 12 hrs. from inocu-lation with A. fumigatus. On the other hand, the lowest mortality and highest survival percent-ages occurred in larvae treated with the fungi-cide Actamyl at 6% and henna at 15% after 12 hrs. from inoculation with A. flavus.
Afficher plus [+] Moins [-]Effect of Electrolysis Technology on Saline Water under Utilize Nano-coated Electrodes
2021
Mohamed Hassan | Arafa Yasser | Khaled elbagoury
In this work, electromagnetic field technol-ogy and electrolysis technology with alumi-num electrodes coated with titanate nano-coat-ing were combined in different investigated parameters: power types (Electrolysis pass (EP) and Electromagnetic pass (EMP)), volt-age (12v, 24v and 36v) and nano-coating pa-rameters (coated and uncoated). The designed water treatment unit was evaluated by record-ing the EC-meter readings for 60min (each 5min) at a flow rate of 5l/min. Results show that the best salt rejection rate was 3.4% when EMP was used before EP where four elec-trodes were coated. In contrast, the other pa-rameters (EP, EMP+EP and EMP+EP (2 coated electrodes and 2 uncoated)) recorded the salt rejection rates 1.13%, 1.57% and 2.4%, respectively. This study is promising and opens the way for integrating both electrolysis and electromagnetic field technologies with on-farm irrigation systems and enhancing their efficiency using nanotechnology.
Afficher plus [+] Moins [-]Nitrogen Nutrition and Adaptation of Halophyte Chenopodium quinoa to Salt Stress
2021
Karema Tarek | Ibrahim Alshamy | Sayed Hussin | Sayed Eisa
There is little evidence that the nitrogen nu-trition supply at rates above or less than what is considered optimal in non-saline conditions improves growth and yield of halophyte crop cultivated under salt stress. Therefore, hypoth-esize of the present work was to find out the magnitude to which N could restore the harm-ful effects of salt stress on quinoa plants. A pot experiment was performed in greenhouse con-ditions to evaluate quinoa's response grown under water salinity treatments (0.0 & 200 mM NaCl) when nitrogen nutrition rates were limiting (50ppm), adequate (250 ppm), and ex-cess (450 ppm) to guide proper application rate of nitrogen fertilizer under salinity stress. The results indicated that, salinity caused a signifi-cant decrease in the vegetative growth of the plant. Consequently, all vegetative measure-ments were negatively affected. As a result, the seed yield decreased to more than 50%. The application of a moderate level of nitrogen (250 ppm) caused a significant ameliorative effect on seed yield by 126% under non saline conditions and 34.5 % under saline conditions compared to the low nitrogen level. The results did not improve any further with the applica-tion of a higher level of nitrogen. These results indicate that applying (N) in adequate may im-prove most traits and prove to be a physiolog-ical treatment to increase resistance against the negative effects of salt stress in quinoa.
Afficher plus [+] Moins [-]Potentiality of Using Mycorrhizae and Pseudomonas fluorescens in Reducing the Effect of Water Shortage on Broccoli Plants
2021
Dalia Abd El-Fattah | Fadl Hashem | Ahmed Farag
Accelerating global warming and water scarcity and improving water use efficiency are considered essential factors for achieving adequate crop development and productivity. Therefore, the authors targeted the use of arbuscular mycorrhizal fungi (AMF) and Pseudomonas fluorescens (Ps1) for improving growth, productivity, and water use efficiency of broccoli plants (Brassica olercea L. var. italica, cv. Belstar F1) under various irrigation regimes i.e., 50, 75, and 100% of crop evapotranspiration (ETc). Two greenhouse experiments were carried out in clayey soil. The combined inoculation of endomycorrhizae and Ps. fluorescens (Ps1) improved water use efficiency and consequently vegetative growth and yield. Under the applied irrigation regime 75% ETc of broccoli inoculated with both endomycorrhizae and Ps. fluorescens (Ps1) showed higher head weight (616 and 647 gram) than those grown under the irrigation regime 75% ETc combined with endomycorrhizae (568 and 559 gram) during the two seasons, respectively. However, a minimum yield value of 149 and 142 grams per plant was recorded for un-inoculated plants grown under 50% irrigation regime during both seasons. In conclusion, the combined inoculation with endomycorrhizae and Ps. fluorescens (Ps1) under irrigation regime 75% ETc was the optimum combination for increasing water stress resistance and broccoli productivity under water scar-city circumstances.
Afficher plus [+] Moins [-]Greenhouse and Laboratory Evaluation of The Efficiency of Green Silicon Dioxide Nanoparticles Against Tetranychus urticae (Koch)
2021
Heba Emam | Manal Ibrahim | Mervat Ibrahim | Salwa El-Sayed
Nanotechnology takes a significant position in controlling pests. Silicon dioxide nanoparticles (SiO2-NPs) is considered one of the best alter-natives to chemical pesticides for plant crop protection from harmful arthro-pods such as phytophagous mites, Tetranychus urticae. Therefore, this study aims to evaluate the effect of (SiO2-NPs) to control T. urticae. Under green-house conditions, the results revealed, in the larval stage, a high mortality percentage (99.05±0.83%) followed by eggs (98.74±1.22%). Besides, the nymph stage recorded high mortality (94.66±1.81%) at a high concentration of 1500 ppm. While the adult females of T. urticae recorded mortality of 91.92±1.02% after 72h. Eventually, the immature stages of T. urticae were susceptible to (SiO2-NPs). Meanwhile, at laboratory evaluation on immature stages of T. urticae which resulted from live treated females during 96h showed a sharp decrease in average numbers of eggs through 96h, at 1000 and 1500 ppm. No numbers of the larval stage were recorded at 1500 ppm. No number of nymph stage were recorded at all concentrations and periods. Moreover, activity of AChE was significantly inhibited at 1500 ppm, while activity of glutathione-S-transferase was significantly increased after 72 h. Finally, (SiO2-NPs) are effective against immature stages of T. urticae under greenhouse and laboratory conditions.
Afficher plus [+] Moins [-]Capabilities of Hyperspectral Remote Sensing Data to Detect Soil Salinity
2021
Abdelrahman Medhat Saleh | Mohammed Abd-Elwahed | Yasser Metwally | Sayed Arafat
The objectives of the current study were to investigate the opportunity of estimating soil salinity from hyperspectral data and identifying the most informative spectral zones for estimation. Electrical conductivity (EC) measurements of ninety topsoil samples (0–30 cm) collected from Toshka, Egypt, were used as data set. Analytical spectral device was employed to collect the reflectance spectral signatures of soil samples. Both linear regression and HSD Tukey’s analyses displayed that the SWIR1 and SWIR2 zones are the most suitable for soil salinity prediction while, blue, green and NIR were the wickedest. Moreover, EC estimation was better in case of lower soil salinity (0-2 dS m-1) than higher levels (8-1). Partial-least-squares-regression (ΡLSR) was employed to establish soil salinity prediction model using the training set of soil samples (n=75). The PLSR model was set up using the most informative wave bands (SWIR1 and SWIR2). The result showed that PLSR linear model gave a precise prediction of soil salinity (R2 = 0.93). The results revealed that employing reflectance values in SWIR in the model variables increases the precision of soil EC prediction.
Afficher plus [+] Moins [-]Management of Irrigation Water for Cucumber Crop by Using Drip Irrigation Systems under Greenhouse
2021
Esraa Masria | Abdelghany Elgandy | Khaled elbagoury | essam wasif
This study aimed to examine the consequences of three regimes for irrigation on cucumber crops and their growth indication, production, and water productivity under greenhouse cultivation. Cucumber seedlings were planted in May 2018 under a greenhouse condition. Three regimes of drip irrigation were examined, first 100%, 80%, and 50% of ETc namely T1, T2, and T3, respectively. The second regime was systems of drip irrigation (sur-face and sub-surface irrigation). Finally, the third was dripper discharge which used (2 l/h and 4 l/h). Results indicated clearly that the best production was under 80% ETc regime by 2 l/h dripper for surface and subsurface that was 10.1 and 11.2 ton/greenhouse respectively with IR 172 m3/season and the best regime by using 4 l/h was 50% ETc for surface and sub-surface respectively which was 11 and 11.5 ton/greenhouse with IR 216 m3/season which saved about half a quantity of irrigation water. On the other hand, the very best water productivity value (WP) was under 80% ETc was 58.7 and 65.4 kg/m3 under surface (S) and sub-surface (SS) drip irrigation respectively by 2 l/h dripper flow rate.
Afficher plus [+] Moins [-]Dissipation of Glyphosate and Glufosinate Ammonium in Soil and Weed Control in Citrus Orchards
2021
Amira Othman | Mohammed El-Zemaity | Walaa El-Sayed | Ahmad Hanafi | Khaled Ramadan
Glyphosate (GLY) and glufosinate-ammonium (GLUA) are broad-spectrum, non-selective, contact herbicides that are commonly used in fruit farms Achieving the separation and detection of glyphosate and glufosinate from soil samples by chromatography is a challenging task as they are ionic and highly water-soluble compounds. The aim of this study is conducted to determine the dissipation of GLY and GLUA applied at two dose levels in three-depth soils of orange orchards. The residues of GLY and GLUA were determined by the HPLC-UV detector. The residual detection limits of GLY and GLUA of the method were 0.03 and 0.05 ng/g in soil respectively. The obtained data indicated that GLY persistent in the soil is very short, only for 7 days, following applications of 1 to 2 kg/fed in the orange crop. GLUA dissipated in soil within 14 days of application, regardless of dose. The half-life (T/2) of GLY and GLUA were 1.68 and 1.42 days at 0 cm depth, respectively. There was no significant difference between the half-life of the two herbicides in soil at three depths. These results showed that GLY dissipation occurs rapidly in soil. However, GLUA was moderately persistent in soil. The two compounds tested showed a reduction of dry weight for four types of weeds after 14 days of recommended and double-rate application.
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