排序方式: 共有65条查询结果,搜索用时 15 毫秒
61.
Sabah Hassan Ahmed Atef Hani M. Ali Rahma Alshamrani Ahmed Ramadan 《Saudi Journal of Biological Sciences》2022,29(5):3647-3653
The major reports on Calotropis procera (C. procera) indicated the importance of this plant as a resource of pharmaceutically active ingredients as well as its medical advantages. β-amyrin (BA) is a significant substance in this plant and has a pharmacological effects in some frameworks, like focal and fringe sensory system, digestive and immune systems. In this study, the impact of sunlight before and after irrigation on the BA production in C. procera is studied its pathway with involved eight key enzymes. The eight enzymes' genes were characterized and successfully submitted to NCBI; AAS (acc.no. KU997645) for α-amyrin synthase, BAS (acc.no. MW976955) for β-amyrin synthase, SE (acc.no. MW976956) for squalene epoxidase, SS (acc.no. MW976957) for squalene synthase, GPPS, (acc.no. MW976958) for geranyl pyrophosphate synthase, FPPS (acc.no. MW976959) for farnasyl pyrophosphate synthase, CAS1, (acc.no. MZ00598) for cycloartenol synthase1 and LS (acc.no. MZ005982) for lupeol synthase. qRT-PCR analysis revealed high expression levels of GPPS, FPPS, SS, SE, and BAS genes at all times specially midday. Otherwise, CAS1, LS and BAS expression levels were very low at all daylight periods. The UPLC β-amyrin data are in accordance with qRT-PCR results. This indicates that triterpenes biosynthetic pathway in C. procera is going to β-amyrin accumulation with the highest level at midday. 相似文献
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Khodran Hamdan Al-Zahrani Mirza Barjees Baig Mark Russell Ahmed Hasan Herab Abduaziz Thabet Mohammed Dabiah Khalid Abdullah Al-Zahrani 《Saudi Journal of Biological Sciences》2021,28(5):2789-2794
PurposeThis research determines the extent to which farmers benefit from agricultural extension activities and services through realizing higher biological crop yields in the Al-Baha region of the Kingdom of Saudi Arabia. Additionally, the nature of the relationship between the personal, economic and social characteristics of farmers and the degree to which they benefit from agricultural extension activities and services are studied.MethodologyA simple random sample representing the community of 315 farmers was drawn. Data were collected through a personal interview with a pre-tested questionnaire to satisfy the objectives of the study. Data are subjected to analyses and are interpreted in terms of percentages, arithmetic averages, and standard deviations in addition to the simple Pearson correlation coefficients.ResultsThe results show that most of the respondents depend on personal experience, friends, family and neighbors, merchants and sellers of agricultural production supplies as sources of agricultural information for enhanced crop yields. Multiple regression analysis reveals that both the educational status and the agricultural information sources are important factors that increase farmers benefit from extension activities. Farmers receive most benefits from the extension activities and services from bringing in foreign workers, conducting field trips to farms, and identifying problems faced by farmers.Research limitations/implicationsThe outcome of this questionnaire limits generalization of the findings for other parts of the Kingdom due to geographical and natural resources variations.Practical implicationsThe personal and socio-economic characteristics of the surveyed population provide the extension service with insight into their composition – a basis to formulate workable extension programs. For the extension planners of the area, this effort provides a baseline study and may assist with targeting the appropriate farmers and catering the right solutions to the problems. Such a study will help devise meaningful extension programs and save time and resources.Originality/valueLittle previous research on the usefulness of the Extension Service has been conducted in the region.ConclusionsEffective, well-planned extension programs targeting the educated and mature farmers provided more benefits and helped them obtain higher crop yields. 相似文献
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Combined effects of NaCl and Cd2+ stress on the photosynthetic apparatus of Thellungiella salsuginea
Rahma Goussi Arafet Manaa Walid Derbali Tahar Ghnaya Chedly Abdelly Roberto Barbato 《BBA》2018,1859(12):1274-1287
Plants show complex responses to abiotic stress while, the effect of the stress combinations can be different to those seen when each stress is applied individually. Here, we report on the effects of salt and/or cadmium on photosynthetic apparatus of Thellungiella salsuginea. Our results showed a considerable reduction of plant growth with some symptoms of toxicity, especially with cadmium treatment. The structural integrity of both photosystems (PSI and PSII) was mostly maintained under salt stress. Cadmium induced a considerable decrease of both PSI and PSII quantum yields and the electron transport rate ETR(I) and ETR(II) paralleled by an increase of non-photochemical quenching (NPQ). In addition, cadmium alone affects the rate of primary photochemistry by an increase of fluorescence at O-J phase and also the photo-electrochemical quenching at J-I phase. A positive L-band appeared with (Cd) treatment as an indicator of lower PSII connectivity, and a positive K-band reflecting the imbalance in number of electrons at donor and acceptor side. In continuity to our previous studies which showed that NaCl supply reduced Cd2+ uptake and limited its accumulation in shoot of divers halophyte species, here as a consequence, we demonstrated the NaCl-induced enhancement effect of Cd2+ toxicity on the PSII activity by maintaining the photosynthetic electron transport chain as evidenced by the differences in ψO, φEo, ABS/RC and TR0/RC and by improvement of performance index PI(ABS), especially after short time of treatment. A significant decrease of LHCII, D1 and CP47 amounts was detected under (Cd) treatment. However, NaCl supply alleviates the Cd2+ effect on protein abundance including LHCII and PSII core complex (D1 and CP47). 相似文献
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In this research article, we investigated the effect of Euphorbia bivonae extract compounds on the lethality of brine shrimp Artemia salina and on embryonic cell lines (HEK293) proliferation. Our GC/MS analysis revealed that the E. bivonae ethanolic extract contained essentially sitosterol, euphol, and lupeol. The 24-h LC50 was determined using the probit analysis method (LC50=357.11 mg l−1). Depending on this cytotoxicity test result, E. bivona extract induced a significant increase in Superoxide Dismutase (SOD), Catalase (CAT), Glutathione-Peroxidase (GPx) activities, and lipid peroxidation (LPO) in A. salina larvae. In addition, the cytotoxicity effect of this extract had proved against the HEK293 cell lines in vitro. We suggest that the three compounds of E. bivonae extract (sitosterol, euphol, and lupeol) are the most responsible for this cytotoxicity. The possible application of this extract as an alternative natural antiproliferative is considered. 相似文献