Assessments of phenolic, flavonoid and antioxidant activity of aqueous, alcoholic, methanol and acetone extracts of thirteen medicinal plants

Phenolic compounds, especially those with plant origin, constitute an essential part of the human diet due to their antioxidant properties. Antioxidants protect biological systems (nucleic acids, proteins, lipids, lipoproteins) against free radicals and reactive oxygen species. Some medicinal plants contain so high amounts of antioxidants that their use can be considerably effective for human health. The aim of this study was to evaluate the effect of flooding extraction method on phenolic compounds, flavonoids and the level of free radical scavenging properties of medicinal plants including Thyme, Hamadani Yarrow, Shirazi mountain thyme, Yarrow, Chamomile, Saffron corm hyssop Sagebrush, wormwood, Artemisia and Ziziphora clinopodioiedes, in four extraction solvents including water, methanol, acetone and ethanol. The results showed that methanol and water solvents had the highest and the lowest total phenolic, flavonoid and antioxidant activity, respectively. The results also showed that methanol extraction of Shirazi thyme and water extraction of Wormwood plant had the highest and the lowest phenol and flavonoids contents, respectively. The results of trapping the free radicals of DPPH indicated that the methanol extract of Shirazi thyme and aqueous extract of wormwood had the highest and the lowest inhibition activities, respectively. Therefore, the selection of solvent type can affect the rate of the extraction of phenolic compounds, flavonoids and antioxidant activity

Transcriptome Analysis Methods: From the Serial Analysis of Gene Expression and Microarray to Sequencing new Generation Methods

Up-to-date research in biology, biotechnology, and medicine requires fast genome and transcriptome analysis technologies to investigate cellular state, physiology, and activity. Gene expression is the process of generating messenger RNA copies of a gene. The transcriptome, which contains the mRNA of the cell, reflects the cell's overall gene expression pattern. Understanding the nature and frequency of each RNA molecule in a given cell under certain circumstances is necessary to examine the transcriptome. Microarray and serial analysis of gene expression are two primary techniques researchers use in transcriptome studies. Here, microarray technology and next-generation sequencing of transcripts are states of the art. Since microarray technology is limited to RNA, quantifying transcript levels and sequence information, RNA-Seq provides nearly unlimited possibilities in modern bioanalysis. Sequencing of RNA, or RNA-Seq, is now a standard method to analyze gene expression and uncover novel RNA species. In addition, aspects of RNA biogenesis and metabolism can be interrogated with specialized techniques for cDNA library preparation. The present study will introduce and compare new high-performance methods used in examining the transcriptome. This also presents a detailed description of next-generation sequencing, describes the impact of this technology on transcriptome analysis, and explains its possibilities to explore the modern RNA world

Current Advances in DNA Methylation Analysis Methods

DNA methylation is one of the epigenetic changes, which plays a major role in regulating gene expression and, thus, many biological processes and diseases. There are several methods for determining the methylation of DNA samples. However, selecting the most appropriate method for answering biological questions appears to be a challenging task. The primary methods in DNA methylation focused on identifying the state of methylation of the examined genes and determining the total amount of 5-methyl cytosine. The study of DNA methylation at a large scale of genomic levels became possible following the use of microarray hybridization technology. The new generation of sequencing platforms now allows the preparation of genomic maps of DNA methylation at the single-open level. This review includes the majority of methods available to date, introducing the most widely used methods, the bisulfite treatment, biological identification, and chemical cutting along with their advantages and disadvantages. The techniques are then scrutinized according to their robustness, high throughput capabilities, and cost