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991.
992.
Muhammad Idrees Bibi Sania Bibi Hafsa Sana Kumari Haji Khan Hina Fazal Ishfaq Ahmad Fazal Akbar Naveed Ahmad Sadeeq Ali Nisar Ahmad 《Comptes rendus biologies》2018,341(6):334-342
Stevia rebaudiana (S. rebaudiana) is the most important therapeutic plant species and has been accepted as such worldwide. It has a tendency to accumulate steviol glycosides, which are 300 times sweeter than marketable sugar. Recently, diabetic patients commonly use this plant as a sugar substitute for sweet taste. In the present study, the effects of different spectral lights were investigated on biomass accumulation and production of secondary metabolites in adventitious root cultures of S. rebaudiana. For callus development, leaf explants were excised from seed-derived plantlets and inoculated on a Murashige and Skoog (MS) medium containing the combination of 2,4-dichlorophenoxy acetic acid (2, 4-D, 2.0 mg/l) and 6-benzyladenine (BA, 2.0 mg/l), while 0.5 mg/l naphthalene acetic acid (NAA) was used for adventitious root culture. Adventitious root cultures were exposed to different spectral lights (blue, green, violet, red and yellow) for a 30-day period. White light was used as control. The growth kinetics was studied for 30 days with 3-day intervals. In this study, the violet light showed the maximum accumulation of fresh biomass (2.495 g/flask) as compared to control (1.63 g/flask), while red light showed growth inhibition (1.025 g/flask) as compared to control. The blue light enhanced the highest accumulation of phenolic content (TPC; 6.56 mg GAE/g DW), total phenolic production (TPP; 101 mg/flask) as compared to control (5.44 mg GAE/g DW; 82.2 mg GAE/g DW), and exhibited a strong correlation with dry biomass. Blue light also improved the accumulation of total flavonoid content (TFC; 4.33 mg RE/g DW) and total flavonoid production (TFP; 65 mg/flask) as compared to control. The violet light showed the highest DPPH inhibition (79.72%), while the lowest antioxidant activity was observed for control roots (73.81%). Hence, we concluded that the application of spectral lights is an auspicious strategy for the enhancement of the required antioxidant secondary metabolites in adventitious root cultures of S. rebaudiana and of other medicinal plants. 相似文献
993.
Corrugation Architecture Enabled Ultraflexible Wafer‐Scale High‐Efficiency Monocrystalline Silicon Solar Cell 下载免费PDF全文
Rabab R. Bahabry Arwa T. Kutbee Sherjeel M. Khan Adrian C. Sepulveda Irmandy Wicaksono Maha Nour Nimer Wehbe Amani S. Almislem Mohamed T. Ghoneim Galo A. Torres Sevilla Ahad Syed Sohail F. Shaikh Muhammad M. Hussain 《Liver Transplantation》2018,8(12)
Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large‐scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon‐based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor‐based integration strategy where corrugation architecture enables ultraflexible and low‐cost solar cell modules from bulk monocrystalline large‐scale (127 × 127 cm2) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 µm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon‐based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 µm of the back contacts is shown that carries the solar cells segments. 相似文献
994.
Precise editing of CLAVATA genes in Brassica napus L. regulates multilocular silique development 下载免费PDF全文
Yang Yang Kaiyu Zhu Huailin Li Shaoqing Han Qingwei Meng Shahid Ullah Khan Chuchuan Fan Kabin Xie Yongming Zhou 《Plant biotechnology journal》2018,16(7):1322-1335
Multilocular silique is a desirable agricultural trait with great potential for the development of high‐yield varieties of Brassica. To date, no spontaneous or induced multilocular mutants have been reported in Brassica napus, which likely reflects its allotetraploid nature and the extremely low probability of the simultaneous random mutagenesis of multiple gene copies with functional redundancy. Here, we present evidence for the efficient knockout of rapeseed homologues of CLAVATA3 (CLV3) for a secreted peptide and its related receptors CLV1 and CLV2 in the CLV signalling pathway using the CRISPR/Cas9 system and achieved stable transmission of the mutations across three generations. Each BnCLV gene has two copies located in two subgenomes. The multilocular phenotype can be recovered only in knockout mutations of both copies of each BnCLV gene, illustrating that the simultaneous alteration of multiple gene copies by CRISPR/Cas9 mutagenesis has great potential in generating agronomically important mutations in rapeseed. The mutagenesis efficiency varied widely from 0% to 48.65% in T0 with different single‐guide RNAs (sgRNAs), indicating that the appropriate selection of the sgRNA is important for effectively generating indels in rapeseed. The double mutation of BnCLV3 produced more leaves and multilocular siliques with a significantly higher number of seeds per silique and a higher seed weight than the wild‐type and single mutant plants, potentially contributing to increased seed production. We also assessed the efficiency of the horizontal transfer of Cas9/gRNA cassettes by pollination. Our findings reveal the potential for plant breeding strategies to improve yield traits in currently cultivated rapeseed varieties. 相似文献
995.
Fahad Al-Qurainy Mohammad Nadeem Salim Khan Saleh Alansi Mohamed Tarroum Abdulhafed A. Al-Ameri Abdel-Rhman Z. Gaafar Aref Alshameri 《Saudi Journal of Biological Sciences》2018,25(1):111-116
Reseda pentagyna is the only endemic species among the seven species of the genera Reseda found in Saudi Arabia. Probably no information is available on regeneration by conventional method of regeneration through seeds or cuttings. Therefore, alternative method of tissue culture was attempted to regenerate and multiply the plant. High shoot regeneration (14.44 shoots/explant) was obtained after four weeks, when shoot cuttings cultured on MS containing BA at 1.0 µM. Other cytokinins e.g., Kn, 2iP and TDZ found to be less effective in bud induction and shoot multiplication. Individual shoots were rooted on MS medium supplemented with various auxins at 0.5–5.0 µM concentrations. The IBA (1.5 µM) supplemented MS media induced maximum (83.3%) rooting. The plantlets were acclimatized and hardened under greenhouse conditions in plastic pots containing soil and farm yard manure with 95.0% success. The protocol developed would help to multiply the plant as well as conserve them in natural habitat. This can also be utilized to obtain active constituents for pharmaceutics and genetic manipulations. 相似文献
996.
Mohammad Attaullah Masarrat J. Yousuf Sohail Shaukat Syed Ishtiaq Anjum Mohammad Javed Ansari Islam Dad Buneri Muhammad Tahir Muhammad Amin Naveed Ahmad Shahid Ullah Khan 《Saudi Journal of Biological Sciences》2018,25(7):1284-1290
Organochlorine pesticides (OCPs) are frequently used worldwide as insecticides, fungicides, herbicides and termiticides and have been associated with a variety of cancers in animal and human studies. In the present study, we examined residues of fourteen OCPs in the serum samples of diagnosed cancer patients and healthy residents of Karachi, Pakistan. A random collection of fasting blood samples was carried out from the donors with informed consent. Serum was separated within 2?h of blood collection and was then subjected to extraction with organic solvents followed by purification with florisil column. The final organic extract of each serum sample was processed with Gas Chromatograph coupled with Electron Capture Detector (GC-ECD). OCPs were detected in 97.59% of the cancer cases and 93.75% of the healthy subjects. Mean concentrations of total OCPs (ΣOCPs) was found elevated in the cancer group (0.606?mg/kg) compared with the control group (0.322?mg/kg). Endosulfan was the highest prevalent OCP with a mean concentration of 0.214?mg/kg in the cancer group and 0.166?mg/kg in the control group. The second most prevalent OCP was 4,4-DDE with a mean concentration of 0.131?mg/kg in the cancer group and 0.019?mg/kg in the control group. Highest level of ΣOCPs was detected in the breast cancer cases (20.411?mg/kg) with a mean level of (2.041?mg/kg). In light of the obtained results and available literature on the subject, it has been concluded that OCPs are positively associated with the risk of various cancers in humans. 相似文献
997.
Saira Bano Shujaul Mulk Khan Jan Alam Abdulaziz A. Alqarawi Elsayed Fathi Abd_Allah Zeeshan Ahmad Inayat Ur Rahman Habib Ahmad Abdullah Aldubise Abeer Hashem 《Saudi Journal of Biological Sciences》2018,25(4):801-810
The present study was conducted to elaborate vegetation composition structure to analyze role of edaphic and topographic factors on plant species distribution and community formation during 2013–14. A mixture of quadrat and transect methods were used. The size of quadrat for trees shrubs and herbs were 10 × 5, 5 × 2, 1 × 1 meter square respectively. Different phytosociological attribute were measured at each station. Primary results reported 123 plant species belong to 46 families. Asteraceae and Lamiaceae were dominant families with 8 species each. PCORD version 5 were used for Cluster and Two Way Cluster Analyses that initiated 4 plant communities within elevation range of 529–700 m from sea level. Indicator species analyses (ISA) were used to identify indicator species of each community. CANOCO Software (version 4.5) was used to measure the influence of edaphic and topographic variables on species composition, diversity and community formation. Whereas Canonical Correspondence Analysis (CCA) was used to measure the effect of environmental variables which showed elevation and aspect were the stronger environmental variable among topographic and CaCO3 contents, electric conductivity, soil pH were the stronger edaphic factors in determination of vegetation and communities of the Bheer Hills. Grazing pressure was one of the main anthropogenic factors in this regard. 相似文献
998.
Salem S. Alghamdi Muhammad A. Khan Ehab H. El-Harty Megahed H. Ammar Muhammad Farooq Hussein M. Migdadi 《Saudi Journal of Biological Sciences》2018,25(1):15-21
This study aimed to estimate the proximate, phenolic and flavonoids contents and phytochemicals present in seeds of twenty four soybeans (Glycine max (L.) Merr) genotypes to explore their nutritional and medicinal values. Crude protein composition ranged between 35.63 and 43.13% in Argentinian and USA (Clark) genotypes, respectively. Total phenolic content varied from 1.15 to 1.77?mg?GAE/g, whereas flavonoids varied from 0.68 to 2.13?mg?QE/g. The GC–MS analysis resulted identification of 88 compounds categorized into aldehydes (5), ketones (13), alcohols (5), carboxylic acids (7), esters (13), alkanes (2), heterocyclic compounds (19), phenolic compound (9), sugar moiety (7) ether (4) and amide (3), one Alkene and one fatty acid ester. Indonesian genotypes (Ijen and Indo-1) had the highest phenolic compounds than others genotype having antioxidant activities, while the Australian genotype contains the maximum in esters compounds. The major phytocompounds identified in majority of genotypes were Phenol, 2,6-dimethoxy-, 2-Methoxy-4-vinylphenol, 3,5-Dimethoxyacetophenone, 1,2-cyclopentanedione and Hexadecanoic acid, methyl ester. The presence of phytochemicals with strong pharmacological actions like antimicrobial and antioxidants activities could be considered as sources of quality raw materials for food and pharmaceutical industries. This study further set a platform for isolating and understanding the characteristics of each compound for it pharmacological properties. 相似文献
999.
1000.
Oral Glucose Tolerance is Associated with Neuroelectric Indices of Attention Among Adults with Overweight and Obesity 下载免费PDF全文
Grace M. Niemiro Sarah K. Skinner Anne M. Walk Caitlyn G. Edwards Michael De Lisio Hannah D. Holscher Nicholas A. Burd Naiman A. Khan 《Obesity (Silver Spring, Md.)》2018,26(10):1550-1557