A Novel Approach for Colorimetric Detection of Glyphosate in Food Based on a Split Aptamer Nanostructure and DNAzyme Activity.

Glyphosate has become the most widely used herbicide worldwide in recent years. There are many concerns about toxicity and mutagenicity from long-term use of glyphosate in humans and animals. Therefore, the methods that can help in easy and quick detection of this chemical compound in food and water are critical. In this work, a biosensor was fabricated by combining the enzymatic properties of a specific DNA G-quadruplex and selectivity of a split aptamer to detect glyphosate in foods and water in a quick and simple colorimetric manner. The color change in this method is based on the oxidation of TMB by the G-quadruplex enzyme and the function of aptamer to trap glyphosate, which is visible to the naked eye in the presence and absence of the herbicide. The biosensor showed its high performance in various real samples of water and foods and provided a detection limit of 1.37 nM (R² = 0.9899) with a linear response range of 100 to 400 nM of glyphosate. This biosensor can provide an innovative, cheap and fast approach for the detection and monitoring of glyphosate in various foods and water.

Dual Detection of microRNAs by a Signal-Off Colorimetric Nanobiosensor Based on Novel Split DNAzyme Nanostructure.

Breast cancer is the most common cancer and the second cause of cancer-related death in women, especially in the age of 20-59 years. It is very important to diagnose it in the early stages of development due to high chance of survival. In this research, the early detection of two microRNAs involved in breast cancer including miR-21 and miR-155 was performed simultaneously using a nanobiosensor based on a special G-quadruplex structure and a colorimetric manner. This nanobiosensor contains two probes (p1, p2) that play a role in the formation of a special structure called DNA-G4. This structure has peroxidase-like properties and can oxidize TMB and produce a blue color. The diagnostic method is designed as a signal off, where the hybridization of probes with microRNA sequences, no DNA-G4 structure is formed and no color change is observed. The results of this study showed that the linear range of response is in the range of 2 to 10 nm and limit of detection in buffer, blood and urine samples was calculated as 0.43 nM, 0.54 nM, and 0.62 nM (R2 = 0.98), respectively. Evaluation using the method for cancer monitoring can be a simple, fast and cost-effective technique.

A novel DNA tweezers-based nanobiosensor for multiple detections of circulating exosomal microRNAs in breast cancer.

Breast cancer is the prevalent disease in women, and diagnosis of it in early stage and takes preventive measures is very critical. Recently, circulating microRNAs have emerged as promising early biomarkers of cancer. MiR-21 and miR-155 are two significant biomarkers that act as oncomir in breast cancer. In this study, to detect both microRNAs in one test simultaneously, a novel colorimetric nanobiosensor was developed upon the peroxidation property of a specific G-quadruplex nanostructure. The nanostructure forms a DNA Nano-Tweezers after self-assembly of three DNA oligonucleotides with target sequences, and TMB (2, 2'-azino-bis (3-ethylbenzothiazo-line-6-sulfonic acid)) is used as a reporter to produce color. The high sensitivity of the nanobiosensor was determined (in buffer and blood) using different concentrations of target sequences with a linear response range from 0 to 10 nM, and detection limit of 0.38 nM (R2 = 0.98). The method precisely detected target sequences from non-target sequences in both buffer and blood media. These findings demonstrate, the nanobiosensor is superior to most previous published works due to its simultaneous dual detection, simplicity, low response time, and cost. The analytical data is convenient for accurately use for clinical purposes to detect breast cancer in early stage, more significantly.

Design and Fabrication of a DNA-copper Nanocluster-based Biosensor for Multiple Detections of Circulating miRNAs in Early Screening of Breast Cancer.

Breast cancer is one of the most prevalent cancers and a significant cause of fatalities in women. Diagnosis of breast cancer faces substantial challenges, owing to the multi-factored nature of the illness. Thus, the necessity for an inexpensive, rapid, and non-invasive diagnostic method that enables early detection with high sensitivity and specificity is of primary significance. In this study, a biosensor based on the fluorescence emission of DNA-templated Cu nanoclusters was designed to simultaneously detect and quantify three significant biomarkers of breast cancer (circulating microRNAs, miR-21, miR-195, and miR-155). Fluorescence spectroscopy, FESEM and TEM microscopy, and DLS confirmed the validation of the biosensor. A detection limit of 1.7 pM with a linearity range of 500 nM to 3 µM was obtained. In conclusion, the innovative selection of three biomarkers, the utilization of the HCR process, and an the elaborated design of probes are considered to be among the most important advantages of this biosensor, enabling it a simultaneous triple diagnosis of the blood specific circulating microRNAs without a need for any enzymes, thermo-cycles, expensive or complex facilities, linkers, fluorescent tags, and time-consuming methods.

A Novel Fluorescence Nanobiosensor based on Modified Graphene Quantum dots-HTAB for Early Detection of Fetal Sexuality with Cell Free Fetal DNA.

Recently, prenatal diagnosis with non-invasive insight is a progressive approach in clinical medicine to prevent the birth of infants with genetic abnormalities. Cell free fetal DNA (cffDNA) makes up approximately 3-6% of the bare DNA in the mother's bloodstream which is produced during pregnancy and can be used to detect fetal sex and disease in the early stages. SRY is a gene located on the chromosome Y which determines the sex of male infants. In this work, a new nanobiosensor based on the fluorescence property of r-GQD@HTAB (reduced graphene quantum dots modified with hexadecyl trimethyl ammonium bromide) was fabricated that can identify the SRY gene in cffDNA with high sensitivity and specificity. A detection limit of 0.082 nM and the linear response range of 0.16-1.5 nM was obtained for the method. It was able to discriminate the target sequence with high specificity from the non-target sequences. This biosensor includes a new graphene quantum dot modified with a surfactant, HTAB which leads to high fluorescence emission of it and then more precise differentiation between ssDNA and DsDNA in a solution. In conclusion, it provides a novel analytical tool for detection of small amount of DNA and fetal sex and genetic diseases in early stage with prenatal and noninvasive tests and applicable for clinical use.

A conductive cell-imprinted substrate based on CNT-PDMS composite.

Cell function regulation is influenced by continuous biochemical and biophysical signal exchange within the body. Substrates with nano/micro-scaled topographies that mimic the physiological niche are widely applied for tissue engineering applications. As the cartilage niche is composed of several stimulating factors, a multifunctional substrate providing topographical features while having the capability of electrical stimulation is presented. Herein, we demonstrate a biocompatible and conductive chondrocyte cell-imprinted substrate using polydimethylsiloxane (PDMS) and carbon nanotubes (CNTs) as conductive fillers. Unlike the conventional silicon wafers or structural photoresist masters used for molding, cell surface topographical replication is challenging as biological cells showed extremely sensitive to chemical solvent residues during molding. The composite showed no significant difference compared with PDMS with regard to cytotoxicity, whereas an enhanced cell adhesion was observed on the conductive composite's surface. Integration of nanomaterials into the cell seeding scaffolds can make tissue regeneration process more efficient.

Design and Fabrication a Gold Nanoparticle-DNA Based Nanobiosensor for Detection of microRNA Involved in Alzheimer's Disease.

MicroRNAs are small RNAs which regulate gene expression by translational repression or degradation of messenger RNAs. Regards to important role of these biomolecules in human disease progress, to produce sensitive, simple and cost-effective assays for microRNAs are in urgent demand. miR-137 in Alzheimer's patients has demonstrated its potential as non-invasive biomarkers in blood for Alzheimer's disease diagnosis and prognosis. This paper describes a novel, sensitive and specific microRNA assay based on Colorimetric detection of gold nanoparticles and hybridization chain reaction amplification (HCR). The new strategy eliminates the need for enzymatic reactions, chemical changes, separation processes and sophisticated equipment. The detection process is visible with the naked eyes and detection limit for this method is 0.25nM which is less than or at least comparable with the previous methods based on colorimetric of AuNPs. The important features of this method are high sensitivity and specificity to differentiate between perfectly matched, mismatched and non-complementary target microRNAs and also decent response in the real sample analysis with blood plasma. In conclusion, the simple and fast nanobiosensor can clinically be used for the early detection of Alzheimer's disease by direct detection of the plasma miR-137 in real clinical samples, without a need for sample preparation, RNA extraction and/or amplification.

A Nanobiosensor Based on Fluorescent DNA-Hosted Silver Nanocluster and HCR Amplification for Detection of MicroRNA Involved in Progression of Multiple Sclerosis.

MicroRNAs (miRNA) are a novel class of small noncoding RNAs with roles in RNA silencing and post transcriptional regulation of gene expression. Due to their roles, miRNA can be considered as new biomarkers for prognosis of diseases such as Multiple sclerosis (MS). Herein, we report a miRNA nanobiosensor based on nucleic acid hybridization chain reaction and highly fluorescent DNA hosted silver nanoclusters (NC). In our method, two types of hairpin oligonucleotide probes, MB1 and MB2, were employed as hybridization chain reaction (HCR) monomers, where MB1 acted as a template for in situ synthesis of fluorescent Ag NC. These monomers were stable in solution but they triggered a cascade of hybridization events once miR-145 (a biomarker of MS in blood) was added to the solution. The process yielded nicked double stranded DNA. The nanobiosensor showed great sensitivity for the detection of target microRNA and excellent limit of detection of about 0.1 nM with high specificity to differentiate sharply between complementary, mismatch, and non-complementary target miRNAs. Alongside the outstanding sensitivity and selectivity, the nanobiosensor exhibited great reproducibility, stability and a decent response in real sample analysis with blood plasma. In conclusion, this simple and highly responsive nanobiosensor can clinically be used for the early detection of MS by direct detection of the plasma miR-145 in real clinical samples, without a need for sample preparation, RNA extraction and/or amplification.

Expression of the circulating and the tissue microRNAs after surgery, chemotherapy, and radiotherapy in mice mammary tumor.

The expression of microRNAs (miRNAs), as novel biomarkers, is subject to change in many cancers. Therefore, the overall profile of miRNAs can be used for detection of cancer type, response to therapies, pathological variables, and other factors related to the disease. In this study, to evaluate miRNA expression associated with the tumor progression and response to treatment, 60 BALB/c mice received subcutaneous injections of 4T1 cells. The study includes ten groups: one group as control, six groups were euthanized at different time points to assess the role of miRNA expression in the tumor progression, and three groups received chemotherapy, radiotherapy, and surgery to evaluate miRNA expression in response to treatment. MicroRNAs were extracted from the breast tumor and the plasma samples, and their relative expressions were quantified using qRT-PCR. MiR-155 expression was increased in the plasma in the early weeks after the cell injection but decreased in the plasma after surgery and radiotherapy and also in tumor samples after chemotherapy and radiotherapy. MiR-10b expression was increased in the late weeks both in the plasma and the tumor and was decreased in the plasma after radiotherapy and surgery and in the tumor after radiotherapy. MiR-21 expression was increased in the plasma and the tumor tissue during the disease progression at the third and the fourth weeks following tumor induction but was decreased in the plasma in all the therapy groups. Interestingly, miR-125a showed a significant decrease during the tumor progression, and its expression was increased after the treatment. Our results showed that the candidate miRNAs could be divided into two groups of oncomiRs and tumor suppressor miR based on their deregulation after tumor growth and treatments. It seems that the oncomiRs in the plasma can be an ideal noninvasive candidate biomarker for the early detection of breast cancer and also for following the response of the common therapies.

Synthesis and Assessment of DNA/Silver Nanoclusters Probes for Optimal and Selective Detection of Tristeza Virus Mild Strains.

Citrus Tristeza virus (CTV) is one of the most destructive pathogens worldwide that exist as a mixture of malicious (Sever) and tolerable (Mild) strains. Mild strains of CTV can be used to immunize healthy plants from more Severe strains damage. Recently, innovative methods based on the fluorescent properties of DNA/silver nanoclusters have been developed for molecular detection purposes. In this study, a simple procedure was followed to create more active DNA/AgNCs probe for accurate and selective detection of Tristeza Mild-RNA. To this end, four distinct DNA emitter scaffolds (C12, Red, Green, Yellow) were tethered to the Mild capture sequence and investigated in various buffers in order to find highly emissive combinations. Then, to achieve specific and reliable results, several chemical additives, including organic solvents, PEG and organo-soluble salts were used to enhance control fluorescence signals and optimize the hybridization solution. The data showed that, under adjusted conditions, the target sensitivity is enhanced by a factor of five and the high discrimination between Mild and Severe RNAs were obtained. The emission ratio of the DNA/AgNCs was dropped in the presence of target RNAs and I0/I intensity linearly ranged from 1.5 × 10(-8) M to 1.8 × 10(-6) M with the detection limit of 4.3 × 10(-9) M.

Use of sulfur-oxidizing bacteria as recognition elements in hydrogen sulfide biosensing system.

Four sulfur-oxidizing bacteria (Thiobacillus thioparus, Acidithiobacillus thiooxidans PTCC1717, Acidithiobacillus ferrooxidans PTCC1646, and Acidithiobacillus ferrooxidans PTCC1647) were used as biorecognition elements in a hydrogen sulfide biosensing system. All the experiments were performed in 0.1 M phosphate buffer solution containing 1-20 ppm H2S with optimum pH and temperature for each species. Although H2 S was applied to the biosensing system, the dissolved O2 content decreased. Dissolved O2 consumed by cells in both free and immobilized forms was measured using a dissolved oxygen sensor. Free bacterial cells exhibit fast response (<200 Sec). Immobilization of the cells on polyvinyl alcohol was optimized using an analytical software. Immobilized A. ferrooxidans and A. thiooxidans retained more than 50% of activity after 30 days of immobilization. According to the data, A. thiooxidans and A. ferrooxidans are appropriate species for hydrogen sulfide biosensor.

The effects of several abiotic elicitors on the expression of genes of key enzymes involved in the parthenolide biosynthetic pathway and its content in feverfew plant (Tanacetum parthenium L.).

Feverfew is an herb used to treat different diseases such as migraine headaches. Due to the economic aspect of its metabolites in the pharmaceutical industry, establishing new approaches to produce the compounds on a large scale is essential. To investigate the effects of stimulators on parthenolide synthesis, feverfew plants were treated with different elicitors, including methyl jasmonate, salicylic acid, NaCl, aluminum oxide, and magnesium aluminate spinel nanoparticles. The expression of genes, E-beta-caryophyllene synthase, Germacrene A synthase, and Costunolide Synthase in the metabolite biosynthesis pathway was examined using qRT-PCR. In addition, parthenolide content, total flavonoids, and polyphenols antioxidant activity were evaluated by HPLC and spectrophotometry. Our results indicated that methyl jasmonate and salicylic acid were more effective on the final concentration of parthenolide, but magnesium aluminate spinel affected the genes' expression, positively. The results show that the elicitors can be used to increase the metabolite in the plant, commercially.

Nanostructures in non-invasive prenatal genetic screening.

Prenatal screening is an important issue during pregnancy to ensure fetal and maternal health, as well as preventing the birth of a defective fetus and further problems such as extra costs for the family and society. The methods for the screening have progressed to non-invasive approaches over the recent years. Limitations of common standard screening tests, including invasive sampling, high risk of abortion and a big delay in result preparation have led to the introduction of new rapid and non-invasive approaches for screening. Non-invasive prenatal screening includes a wide range of procedures, including fetal cell-free DNA analysis, proteome, RNAs and other fetal biomarkers in maternal serum. These biomarkers require less invasive sampling than usual methods such as chorionic villus sampling, amniocentesis or cordocentesis. Advanced strategies including the development of nanobiosensors and the use of special nanoparticles have provided optimization and development of NIPS tests, which leads to more accurate, specific and sensitive screening tests, rapid and more reliable results and low cost, as well. This review discusses the specifications and limitations of current non-invasive prenatal screening tests and introduces a novel collection of detection methods reported studies on nanoparticles' aided detection. It can open a new prospect for further studies and effective investigations in prenatal screening field.

Effect of mixed culture of yeast and microalgae on acetyl-CoA carboxylase and Glycerol-3-phosphate acyltransferase expression.

In recent years, some studies have reported that co-culturing green algae and yeast improve lipid and biomass concentration. In this study, a co-culture of the oleaginous yeast Rhodotorula glutinis and the microalgae Chlorella vulgaris was consequently conducted with inoculation of microalga and yeast in growth and stationary phases, respectively. For the first time, the expression of two pivotal enzymes in fatty acids synthetic pathway, acetyl-CoA carboxylase and Glycerol-3-phosphate acyltransferase, was evaluated. To evaluate the synergistic impacts of the mixed culture on the enzymes expression, several co-culture models were designed, including the use of different ratio of microalgae to yeast or the use of residual cell-free medium of yeast; a positive impact on enzymes overexpression was shown in the case of the co-culture of the two microorganisms, and when the remaining cell-free medium of yeast was added to the microalgal culture. The results of in vitro co-culture demonstrated increased 6- and 5-fold of nervonic acid (C24:1) and behenic acid (C22:0) concentrations, respectively, in 2:1 microalgae to yeast co-culture as compared to the monoculture batches. Addition of yeast residual cell-free medium in the 2:1 ratio to the microalgal culture enhanced 9 and 6 times nervonic acid (C24:1) and behenic acid (C22:0) amounts, respectively.

A MYB gene from wheat (Triticum aestivum L.) is up-regulated during salt and drought stresses and differentially regulated between salt-tolerant and sensitive genotypes.

Crop adaptation to abiotic stresses requires alterations in expression of a large number of stress protection genes and their regulators, including transcription factors. In this study, the expression levels of ten MYB transcription factor genes from wheat (Triticum aestivum) were examined in two recombinant inbred lines contrasting in their salt tolerance in response to salt or drought stress. Quantitative RT-PCR analysis revealed that four MYB genes were consistently up-regulated in the seedling roots of both genotypes under short-term salt treatment. Three MYB genes were found to be up-regulated in both genotypes under long-term salt stress. One MYB gene was up-regulated in both genotypes under both short- and long-term salt stress. Of these salt up-regulated MYB genes, one MYB gene (TaMYBsdu1) was markedly up-regulated in the leaf and root of wheat under long-term drought stress. In addition, TaMYBsdu1 showed higher expression levels in the salt-tolerant genotype than in the susceptible genotype under salt stress. These data suggest that TaMYBsdu1 is a potentially important regulator involved in wheat adaptation to both salt and drought stresses.

Design, fabrication, and optimization of a dual function three-layer scaffold for controlled release of metformin hydrochloride to alleviate fibrosis and accelerate wound healing.

Abnormal wound healing caused by the over-expression of collagen and fibronectin leads to fibrosis, the major complication of all treatment modalities. A three-layer nanofiber scaffold was designed, optimized, and fabricated. This scaffold comprised two supportive polycaprolactone (PCL)-chitosan layers on the sides and a polyvinyl alcohol (PVA)-metformin hydrochloride (metformin-HCl) in the middle. The physico-chemical properties of scaffold, such as mechanical characteristics, degradation, swelling, and in-vitro drug release, were evaluated. The biological tests, including cell viability in response to metformin-HCl and Tween 80, scaffold biocompatibility, cell attachment, and antibacterial activity, were further conducted. The wound healing effect of scaffold loaded with metformin-HCl (MSc+Met) was assessed in donut-shaped silicone splints in rats. Histopathological and immunohistochemical evaluation as well as mRNA expression levels of fibrosis markers were also studied. SEM images indicated a uniform, bead-less morphology and high porosity. Surface modification of scaffold by Tween 80 improved the surface hydrophilicity and enhanced the adhesion and proliferation of fibroblasts. The scar area on day 15 in MSc+Met was significantly lower than that of other groups. Histopathological and immunohistochemical evaluation revealed that group MSc+Met was the best, having significantly lower inflammation, higher angiogenesis, the smallest scar width and depth, maximum epitheliogenesis score, and the most optimal modulation of collagen density. Local administration of metformin-HCl substantially down-regulated the expression of fibrosis-involved genes: transforming growth factor (TGF-ß1), collagen type 1 (Col-I), fibronectin, collagen type 3 (Col-III), and alpha-smooth muscle actin (α-SMA). Inhibiting these genes alleviates scar formation but delays wound healing; thus, an engineered scaffold was used to prevent delay in wound healing. These results provided evidence for the first time to introduce an anti-fibrogenic slow-releasing scaffold, which acts in a dual role, both alleviating fibrosis and accelerating wound healing.

A signal-on nanobiosensor for VEGF165 detection based on supraparticle copper nanoclusters formed on bivalent aptamer.

In this study, a signal-on nanobiosensor based on bivalent aptamer-Cu nanocluster was designed and optimized for specific and sensitive detection of VEGF165. The VEGF165 is known as a promising biomarker in different diseases such as cancer in the angiogenic stage. Detection and quantification of VEGF165 is a crucial step in diagnosis and monitoring the treatment plan. The represented nanostructure consists of multimerized VEGF165 aptamer joint with ssDNA based linker in the middle and poly thymine sequences on both 3' and 5' ends as a template for Cu-nanocluster supraparticle formation. This self-assembled structure leads to accurate controlling of aggregation in the presence of VEGF165. This study is the first report for Cu nanocluster nucleation on ploy thymine tails of ssDNA which performed in two reduction steps to form stable CuNC supraparticle. The sensing strategy was designed based on the target-induced structure switching mode of the aptamer. In the presence of VEGF165, due to self-assembly induced emission and aggregation-induced emission phenomena this nanostructure depicted the visible wavelength shift and enhancement in the fluorescence emission intensity. Also, the results of the analytical performance of this nanobiosensor indicated the LOD of 12 pM which revealed high rate sensitivity. This aptasensor exhibited stability and decent response linearity range (10-800 pM, R2 = 0.9943). The selectivity and specificity assessment showed high discriminant capability in the real serum sample. In conclusion, this signal-on nanobiosensor provides a facile, sensitive and reliable assay for clinical monitoring of the VEGF165 concentration in serum without further sample preparation.

A nanobiosensor based on graphene oxide and DNA binding dye for multi-microRNAs detection.

Multiplex assays for detection of biomarkers, provide advantageous analyses of different factors related to diagnoses of diseases. The Alzheimer's disease (AD) is one of the most common disease in old people in societies which is increasing, significantly. A group of microRNAs (miRNAs) play an important role in developing the disease which can be considered as early stage biomarkers. Since, selective, sensitive, simple and rapid method for detection of these miRNAs in a single test is critical for early diagnosis and efficient therapy of the disease, herein, we report a sensitive fluorescence assay based on enzyme-free and isothermal hybridization chain reaction with SYBR Green and graphene oxide (GOX) for early detection of miR-137 and miR-142, as two Alzheimer's biomarkers. Fluorescence spectrophotometry based on SYBR Green signal and GOX as the fluorescence quencher was used for detection and quantification of targets' miRNAs and change in fluorescence intensity due to absence and presence of the targets was measured. The limit of detection in the newly designed nanobiosensor was achieved as 82 pM with a sensitive detection of the miRNAs from 0.05 to 5 nM, that is critical for detecting the biomarkers. Given the real range of concentrations of miRNAs in blood (from nanomolar to femtomolar values), the method holds great promise in dual and multiple targets detection due to its sensitivity, rapidness, inexpensive and specificity which provides a convenient detection method of Alzheimer's in early stage.

Effects of Lactobacillus acidophilus and Bifidobacterium bifidum Probiotics on the Expression of MicroRNAs 135b, 26b, 18a and 155, and Their Involving Genes in Mice Colon Cancer.

A wide range of sources supports that the link between diet and colorectal cancer may be due to an imbalance of the intestinal microflora. In this case, it seems that the probiotics may have a possible molecular mechanism via microRNAs (miRNAs). The present study is aimed to evaluate the effects of Lactobacillus acidophilus and Bifidobacterium bifidum probiotics on the expression of miRNAs 135b, 26b, 18a, and 155 and their target genes, including APC, PTEN, KRAS, and PU.1 in mouse azoxymethane (AOM)-induced colon cancer. Thirty-eight male BALB/c mice were randomly divided into four groups: the control, AOM, Lactobacillus acidophilus, and Bifidobacterium bifidum to deliberate the effects of the probiotics on the miRNAs and their target genes. Except for the control group, the rest groups were weekly given AOM (15 mg/kg, s.c) in three consecutive weeks to induce mouse colon cancer. The animals were given 1.5 g powders of L. acidophilus (1 × 109 cfu/g) and B. bifidum (1 × 109 cfu/g) in 30 cc drinking water in the related groups for 5 months. At the end of the study, the animals were sacrificed and their blood and colon samples were removed for the molecular analyses. The results showed that the expression of the miR-135b, miR-155, and KRAS was increased in the AOM group compared to the control group in both the plasma and the colon tissue samples, and the consumption of the probiotics decreased their expression. Moreover, the miR-26b, miR-18a, APC, PU.1, and PTEN expressions were decreased in the AOM group compared to the control group and the consumption of the probiotics increased their expressions. It seems that Lactobacillus acidophilus and Bifidobacterium bifidum though increasing the expression of the tumor suppressor miRNAs and their target genes and decreasing the oncogenes can improve colon cancer treatment.

Effect of nanoparticle treatment on expression of a key gene involved in thymoquinone biosynthetic pathway in Nigella sativa L.

Thymoquinone is the most important secondary metabolite in black Cumin, which has several pharmaceutical applications. In this study, effect of TiO2 and SiO2 nanoparticles as new elicitors, on expression of Geranyl diphosphate synthase gene (GPPS gene), as a key gene involved in thymoquione biosynthesis pathway was investigated in two Iranian accessions. Plants were treatment in the early flowering stage and after 24 h of 50 and 100 mg/L of each nanoparticle, separately. After RNA extraction, GPPS gene expression was analysed by qRT-PCR method. The results showed that the TiO2 and SiO2 nanoparticles, generally stimulates the GPPS expression. The TiO2 nanoparticles were more effective than SiO2 for the induction of GPPS expression. Also, 100 mg/L treatment of nanoparticles raised gene expression more than 50 mg/L concentration. It can be concluded these nanoparticles can be used as robust elicitors to enhance the production of Thymoquinone in black cumin through up-regulation of related metabolic pathway genes.