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841.
H. M. Abd el-Samad 《Biologia Plantarum》1993,35(4):561-566
Salinity inhibited growth, and affected the contents of chlorophylls, carotenoids, saccharides, amino acids, proteins, DNA and RNA in broad bean plants. Foliar application of NaH2PO4 and NaNO3 greatly ameliorated the adverse effects of NaCI. This counteraction was associated with an increase in contents of saccharides, proteins, DNA and RNA. 相似文献
842.
Mohamed H. Abd El-Razek Ibrahim A. Saleh Sally Abdel-Halim Shaymaa M. Bata Ahmed F. Essa Taha A. Hussien Ahmed A. El-Beih Tarik A. Mohamed Mohamed-Elamir F. Hegazy 《化学与生物多样性》2023,20(8):e202201249
In the current study, both the essential oil composition and biological activity of Saussurea lappa and Ligusticum sinensis were investigated by means of microwave-assisted hydrodistillation (MAHD) and characterized by Gas chromatography/mass spectrometry (GC/MS), whereas the antimicrobial efficiency of MAHD essential oils was examined against four pathogens: Staphylococcus aureus, Escherichia coli, Aspergillus niger, and Candida albicans responsible for microbial infections. The goal was to spot synergy and a favorable method that gives essential oils to possibly use as alternatives to common antimicrobial agents for the treatment of bacterial infections using a microdilution assay. S. lappa's 21 compounds were characterized by MAHD extraction. Sesquiterpene lactones (39.7 % MAHD) represented the major components, followed by sesquiterpene dialdehyde (25.50 % MAHD), while L. sinensis's 14 compounds were identified by MAHD extraction. Tetrahydroisobenzofurans (72.94 % MAHD) was the predominant compound class. S. lappa essential oil collection showed the strongest antimicrobial activity with MIC values of 16 μg/ml against all pathogens tested, while L. sinensis showed strong antibacterial activity and moderate antifungal activity with MIC values of 32 μg/ml and 500 μg/ml, respectively. The principal components of both oils, (velleral, eremanthin and neocnidilide), were docked into the bacterial histidine kinase (HK) and the fungal heat shock protein 90 (Hsp90). 相似文献
843.
844.
Maswada Hanafey F. Abd El-Razek Usama A. El-Sheshtawy Abdel-Nasser A. Mazrou Yasser S. A. 《Journal of Plant Growth Regulation》2021,40(2):558-573
Journal of Plant Growth Regulation - Owing to water scarcity and environmental hazards of synthetic fertilizers, reducing water and chemical N fertilizers is very urgent for sustainable... 相似文献
845.
The effect of the topical application of the synthetic juvenile hormone JH-I on adult specimens of Musca domestica vicina Macq was studied. The adult stage responded to different JH-I concentrations in different ways. The gonotrophic cycle was shortened, the number of eggs decreased and the hatching rate was reduced. The adults of the next generation displayed a number of anomalies. The ovarian amino acid concentrations varied considerably according to the dose of JH-I and the stage of maturation of the relevant ovary. 相似文献
846.
847.
The removal of two eyestalks from Penaeus kerathurus (Leach) in the middle of the intermoult period was followed by very poor survival. Unilateral ablation was found to be sufficient for the induction of full maturation of the ovaries. 相似文献
848.
Summary The nature of the nitrogenous products formed in the cells and culture solutions of a nitrogen fixing strain of Nostoc commune was investigated. This organism was able to fix 5.4 mg nitrogen/100 mg dry algal cells. 13% of this cellular nitrogen was present in the soluble form. The assay of the different fractions of this soluble nitrogen was also made. Aspartic acid, glutamic acid and alanine were the only amino acids present in the free form. The extracellular nitrogen amounted to 30% of the total fixed nitrogen. The different fractions of this nitrogen were also assayed. Glutamic acid and aspartic acid were the only free amino acids in the culture solution. The importance of these two acids in the pathway of the fixation mechanism was discussed. 相似文献
849.
Summary Seeds ofTrifolium andTrigonella were planted after exposure to different dose rates 61.0, 75.8, 116.6 and 265.0 r/day from a radium tube for a period of seven days. The general effect was a tendency towards increase in the number of nodules and of lateral roots per plant, especially at a total dose of about 816 r.Colchicine treatment was found to have a similar effect. 相似文献
850.
Omneya Eid Wafaa M. Elkady Shahira Ezzat Abeer El Sayed Essam Abd elsattar 《化学与生物多样性》2023,20(3):e202200935
Barley (Hordeum vulgare L.) is one of the world's oldest cereal crops. There is considerable interest in barley's potential usage in human diets. Barley is rich in bioactive metabolites such as high content of β-glucan, fiber, and vitamin E. It is also well-known as a rich source of phytochemical derivatives, namely, phenolic acids, flavonols, chalcones, flavones, proanthocyanidins, and flavanones. Phenolic compounds are recognized as excellent dietary materials with antioxidant and anti-inflammatory activities. This review was written to give an overview of the main components that are separated from barley using different solvents. Even though there were numerous biological activities for barely, the antioxidant, as well as the anti-inflammatory, are the main focus of this review. 相似文献