M. Zeynali; B. Maleki Zanjani; P. Moradi; F. Shekari; S.M. Niazkhani
Abstract
Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five ...
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Biological stresses such as drought affect the production of secondary metabolites, especially plant sterols (phytosterols). Among the phytoestrols found in pumpkin seeds, betasitosterol is one of the most important components which also have many medicinal properties. In this study, the effect of five levels of drought stress on seed oil production and its phytosterols was studied in three genotypes and Styriaca variety of pumpkin (Cucurbita pepo L.). Analysis of phytosterols using GC/MS showed that increasing drought stress had a negative effect on oil production from pumpkin ripe seeds, but oil phytosterols, especially betasitosterol, increased and this increase was higher in Styriaca than other genotypes. To confirm these results, the seeds were harvested 15-30 days after flowering and the expression of SQS, PP2A, SMT2, ERG26 and Cycloartenol synthase genes involved in the phytosterol biosynthesis pathway was investigated. The results indicated that, among the different levels of drought stress and genes studied, highest expression level was observed at the rainfed level and at that time, betasitosterol and stigmasterol pathway had the main activity in steroid biosynthesis pathway in pumpkin.
S. Pirtarighat; M. Ghannadnia
Abstract
Melissa officinalis L. (Lamiaceae) has been used as an important medicinal herb since ancient times. The study of the biosynthetic pathways of the plant medicinal metabolites is of particular importance in identifying the materials affecting these pathways in order to change the quantity or quality of ...
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Melissa officinalis L. (Lamiaceae) has been used as an important medicinal herb since ancient times. The study of the biosynthetic pathways of the plant medicinal metabolites is of particular importance in identifying the materials affecting these pathways in order to change the quantity or quality of the medicinal metabolites. The metabolic pathway of phenylpropanoid includes sophisticated pathways of biochemical reactions that synthesize a set of secondary plant metabolites such as flavonoids, isoflavonoids, lignins, anthocyanins, etc. Phenylalanine ammonia-lyase (PAL) and 4-coumarate-CoA ligase (4CL) are two main enzymes of the phenylpropanoid pathway, playing a fundamental role in the biosynthesis of plant phenolic compounds. Regarding the fact that stress and environmental changes lead to changes in the expression of certain genes in plants, in this study, the gene expression of two PAL and 4CL enzymes was investigated using Real-Time PCR technique in Melissa officinalis L. grown under in vitro conditions treated by calcium chloride. Moreover, the total protein was extracted and quantitatively measured. The results showed that increasing and decreasing calcium chloride by 880 and 220 (mg l-1) caused reduced PAL gene expression and increased 4CL gene expression, respectively. Also, the total plant protein content decreased by 585 and 595 (g l-1) in 880 and 220 (mg l-1) of calcium chloride treatment, respectively. According to Fourier-transform infrared spectroscopy (FTIR) analysis, it was found that some phenolic compounds, carbohydrates, lipids, and proteins decreased in calcium chloride treatment than the control group. These results show the effect of calcium ion on the regulation of some genes expression and the production of their metabolites. Therefore, by changing the amount of calcium, the controlled amount of plant compounds could be achieved for specific purposes.
H. Mousavi; N. Mahdi Nezhad; B. Fakheri; M. Majdi; F. Heidari
Abstract
To investigate the effects of nano-chelate spraying of Iron, chemical -synthesis and green-synthesis silver nanoparticles on the expression of two genes, germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes which are involved in the parthenolide biosynthesis pathway of Tanacetum parthenium ...
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To investigate the effects of nano-chelate spraying of Iron, chemical -synthesis and green-synthesis silver nanoparticles on the expression of two genes, germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes which are involved in the parthenolide biosynthesis pathway of Tanacetum parthenium L., a factorial experiment based on randomized complete block design was conducted with three replications. The experiment took place in the greenhouse of Zabol University in Iran. At first, the total RNA from samples of leaves, and then the synthesis of cDNA were extracted. Afterward, Real Time PCR analysis was used to determine gene expression patterns. Parthenolide concentration was measured by high-performance liquid chromatography (HPLC). The analysis of the data was conducted by SAS software, and there was a significant increase in the expressions of both germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes of treated plants with green-synthesis silver nanoparticles in compare with the control plants, and some plants which were treated by chemical- synthesis silver nanoparticles and nano-chelate of Iron. Furthermore, the maximum expressions of both germacrene A synthase (TpGAS) and parthenolide synthase (TpPTS) genes were identified in groups of plants which were under the influence of drought stress, or were treated by green-synthesis silver nanoparticles. A positive relation was seen between the expressions of germacrene A synthase genes (TpGAS) and parthenolide synthase (TpPTS) genes with the amount of parthenolide itself. It can be concluded that green-synthesis silver nanoparticles and water deficit stress can cause an increase on the expressions of parthenolide and germacrene A synthase genes, and as result of that, cause an increase on parthenolide production of Tanacetum parthenium.
M. Azizkhani; R. Aznar; P. Elizaquivel
Abstract
Staphylococcal food poisoning is resulted from the consumption of a food in which enterotoxigenic staphylococci have grown and produced toxins. Targeting bacterial virulence factors is now gaining interest as an alternative strategy to develop new types of antimicrobial preservatives. The purpose of ...
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Staphylococcal food poisoning is resulted from the consumption of a food in which enterotoxigenic staphylococci have grown and produced toxins. Targeting bacterial virulence factors is now gaining interest as an alternative strategy to develop new types of antimicrobial preservatives. The purpose of this study was to determine the effect of R. officianalis L. (Ros) essential oil (EO) on growth and gene expression of enterotoxins A, C, and E in Staphylococcus aureus ATCC 29213. In this study, after determining the minimum inhibitory concentration, the growth and secretion of SEA, SEC, and SEE (detected by ELISA method) by S. aureus treated with graded subinhibitory concentrations of EO was evaluated. In addition, the influence of the EO on the transcription of sea, sec and see (the genes encoding SEA, SEC and SEE, respectively) was analyzed by quantitative RT-PCR. Ros EO at a concentration of 75% MIC, significantly, reduced the growth of S. aureus. EO inhibited the transcription of sea, sec and see in S. aureus, in a dose-dependent manner, resulting in a reduction of SEA, SEC and SEE secretion. These data suggest that the Ros EO may be useful as a natural preservative against the growth and enterotoxin production of S.aureus in food industry.
