javad ghasemian

DNA-based techniques are more interesting for the taxonomic study of medicinal plants than the classical methods. DNA isolation from medicinal plants due to the higher secondary metabolites is faced with some difficulties. In this study, five protocols, including the original Doyle and Doyle method, two modified Doyle and Doyle methods in which 2-mercaptoethanol or ammonium acetate were removed, modified Murray and Thompson method, and Gene All kit were assayed to select an appropriate method for the DNA extraction of fresh and herbarium leaves of Echium amoenum Fisch. & C.A. Mey. The quality and quantity of the DNA were examined by gel electrophoresis and spectrophotometric analysis. The applicability of the purified DNA was checked by the PCR of nuclear ribosomal DNA internal transcribed spacer (ITS) sequence. Compared to the original Doyle and Doyle method, the elimination of 2-mercaptoethanol or ammonium acetate had no significant effects (p-value > 0.05) on the quantity and quality of the extracted DNA from fresh and herbarium E. amoenum. Although the highest DNA concentration was obtained by the modified Murray and Thompson method from herbarium leaves, the ITS region was not amplified in this sample. The expected PCR products of the ITS region were amplified from the other DNA samples. In conclusion, the easier modified Doyle and Doyle method by eliminating 2-mercaptoethanol or ammonium acetate is beneficial for DNA extraction from both fresh and herbarium leaves of E. amoenum. This modification does not negatively effect on the following PCR step.

The protection of genetic resources is crucial for safeguarding national assets as natural resources face various threats such as climate change and changing land use. To conserve endangered species such as Astragalus fridae, an endemic species of gypsum soils of Semnan province (Iran) which is on the brink of extinction due to limited distribution and habitat destruction, establishing a gene bank is essential. To ensure the survival of this species, it is necessary to extract high-quality and high-quantity DNA. The present survey, has evaluated five genome extraction methods including Protocol A (main CTAB), Protocol B (CTAB without β-mercaptoethanol), Protocol C (CTAB without ammonium acetate), Protocol D (the modified Murray & Thompson method), and Protocol E (GeneAll Plant Kit), to determine their ability to extract DNA from fresh and herbarium leaves of A. fridae. The quality and quantity of DNA were assessed using gel electrophoresis, spectrophotometry, and usability of the purified DNA tested by PCR of the ITS region of nuclear ribosomal DNA. Protocol D yielded the highest quality of the extracted genome from fresh leaves, and Protocol A, extracted the highest DNA concentration from fresh leaves. Although Protocols B and C extracted a reasonable amount of genome of acceptable quality with dry leaves, the ITS region was not amplified in these samples, rendering them unsuitable for DNA extraction of A. fridae.

Extracting high-yield, high-quality DNA from plant samples is challenging due to the presence of the cell wall, pigments, and some secondary metabolites. The main CTAB method, two of its modified protocols (beta-mercaptoethanol or ammonium acetate were eliminated), the modified Murray and Thompson method, and the Gene All kit were statistically compared based on the quantity and quality of the total DNA (tDNA) extracted from fresh and dried leaves of three medicinal herbs P. harmala, T. ramosissima, and P. reptans. The suitability of the tDNAs for molecular studies was evaluated by polymerase chain reaction (PCR) of the fragments of the internal transcribed spacer (ITS) in nuclear DNA and the trnL-F region in chloroplast DNA. Some significant differences were found between the tDNAs extracted by five extraction methods. With the exception of P. harmala, where the PCR of both the ITS fragments and the trnL-F region worked successfully in all DNA samples, but only the ITS fragments, not the chloroplast trnL-F region, were amplified in the DNA samples of T. ramosissima and P. reptans. The chloroplast trnL-F region was amplified only in DNA samples extracted from fresh and dried leaves of the three studied herbs using the commercial kit. Gene All kit, the main CTAB method, and its modified protocols were the less time-consuming protocols that yielded DNA suitable for downstream PCR vis-a-vis the modified Murray and Thompson method.

The purpose of this study is to calculate the risk sensitivity parameters (Greeks) for the European Option by using finite difference method. There are several ways to quantify these risks, each with its own advantages and disadvantages. The most important of these methods are: 1- Analytical method (solving Black Scholes partial differential equation) 2- Monte Carlo simulation method 3- Network methods 4- Finite difference method, Calculating the risk sensitivity parameters in finite difference method The complexity is less complex and the computation time is relatively low, and as the sample increases and the oscillation increases, the parameters are not disturbed. In this study, while introducing finite difference method, 10 top stock companies were selected in 1397 and the value of European trading authority and its risk sensitivity parameters were calculated by MATLAB software. Finally, numerical methods show that the results of finite difference method for calculating Option value and risk sensitivity parameters are approximations of these variables obtained from analytical method (exact method).