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The results obtained herein indicate that walnut chloroform fraction may contain effective compounds which can be used as a chemotherapeutic agent.

To gain a better insight into the selenium nanoparticle (nSe) benefits/toxicity, this experiment was carried out to address the behavior of bitter melon seedlings to nSe (0, 1, 4, 10, 30, and 50 mgL-1) or bulk form (selenate). Low doses of nSe increased biomass accumulation, while concentrations of 10 mgL-1 and above were associated with stem bending, impaired root meristem, and severe toxicity. Responses to nSe were distinct from that of bulk in that the nano-type exhibited a higher efficiency to stimulate growth and organogenesis than the bulk. The bulk form displayed higher phytotoxicity than the nano-type counterpart. According to the MSAP-based analysis, nSe mediated substantial variation in DNA cytosine methylation, reflecting the epigenetic modification. By increasing the concentration of nSe, the expression of the WRKY1 transcription factor linearly up-regulated (mean = 7.9fold). Transcriptions of phenylalanine ammonia-lyase (PAL) and 4-Coumarate: CoA-ligase (4CL) genes were also induced. The nSe treatments at low concentrations enhanced the activity of leaf nitrate reductase (mean = 52%) in contrast with the treatment at toxic concentrations. The toxic concentration of nSe increased leaf proline concentration by 80%. The nSe supplement also stimulated the activities of peroxidase (mean = 35%) and catalase (mean = 10%) enzymes. The nSe-treated seedlings exhibited higher PAL activity (mean = 39%) and soluble phenols (mean = 50%). The nSe toxicity was associated with a disrupted differentiation of xylem conducting tissue. The callus formation and performance of the explants originated from the nSe-treated seedlings had a different trend than that of the control. This experiment provides new insights into the nSe-associated advantage/ cytotoxicity

The effects of exogenous silicon (Si) on salt (NaCl)-stressed borage (Borago officinalis L.) plants were investigated in this study. Six levels of Si (0, 0.5, 1, 1.5, 2, 2.5 mM) and two levels of NaCl (0 and 120 mM) were applied to study the effect of NaCl and Si on some physiological, biochemical and anatomical properties of Borago officinalis L. Salt stress reduced fresh and dry weight, protein contents and catalase activity. In contrast, proline, glycine betaine, malondialdehyde and activity of superoxide dismutase and ascorbate peroxidase increased in salt-stressed plants. The results of anatomical study of leaf cross section showed that salt stress resulted in noticeable anatomical variations such as increase in thickness of leaf blade and thickness of palisade parenchyma cells. Other interesting variations in salt stress include changes in structure and numbers of trichome and stomata. Si treatment in comparison with the plants only treated with salt resulted in an improvement in the studied physiological parameters, especially at 1.5 mM level. Also, Si treatment could moderate the negative effects of salt treatment on the studied anatomical attributes.

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