جستجوی مقالات مرتبط با کلیدواژه « الیسیتور » در نشریات گروه « زیست شناسی »

Taxol is an anti-cancer drug and can be extracted from the yew tree. The aim of this study was to investigate the effects of Methyl jasmonate and Salicylic acid elicitors on taxol production in hairy roots formed in Iranian yew. Three strains of Agrobacterium rhizogenes A4, R1000 and ATCC15834 were used to create hairy roots in yew explants. The results showed that only A4 strain caused the formation of hairy roots in the explants and PCR analysis showed that the Agrobacterium rooting gene was transferred to the explants. In the operation of growing hairy roots, three concentrations of 1, 10 and 100 µmol of methyl jasmonate and salicylic acid were used separately and in combination to increase paclitaxol production. The analysis performed by HPLC showed that the addition of elicitors to the culture medium increases the amount of taxol in hairy roots, and the greatest increase was obtained by adding 100 micromoles of methyl jasmonate alone, which increased the amount of paclitaxol production in hairy roots by 5 times.

Considering the importance of medicinal compounds in medicinal plant species, the production of secondary medicinal metabolites through callus cultivation and subsequent elicitation is economical and time-saving. Levisticum officinale Koch. is one of the valuable indigenous rangeland plants of Iran, which has many medicinal and industrial properties. This study was carried out to optimize callus induction and the effects of different concentrations of GO-SiO2 on the amounts of different secondary metabolites and antioxidant activity under callus culture. For callus induction, the hypocotyl explants were transferred to Murashige and Skoog (MS) culture medium containing different growth regulators. Analysis of variance showed that different plant growth regulators had a significant effect on The MS media supplemented with 1.5 mg/L 2,4-D + 0.025 mg/L (NAA) + 0.5 Kin showed the best percentage of callus production (95%). In order to investigate the effect of the elicitor on the amount of secondary metabolites in the callus, different concentrations of GO-SiO2 (0, 5, 10 and 20 mg/L) were chosen as elicitors. The selected nanoparticle showed positiveand stimulatory effects on the amount of secondary metabolites and antioxidant activity in the callus. The highest content for total phenolics (47.26 mg GAE/g FW), total flavonoids (28.06 mg QE/g FW) and antioxidant activity FRAP (0.096 μ mol /g extract) was observed under 10 mg/L of GO-SiO2. The highest contents for total flavonols (8.18 mg QE /g FW), H2O2 (5.09 μmol/g FW) and total anthocyanin (0.07 μmol/g FW) were observed under 20 mg/L GO-SiO2 treatment. The highest level of carotenoid content (28.11 mg/g FW) and chlorophyll (23.58 mg/g FW) were observed under 5 mg/ L GO-SiO2. The results of this study can be used to optimize the production of secondary medicinal metabolites in this valuable medicinal plant. According to the results of this study, the application of graphene oxide nanopaGO-SiO2 (10 mg/L) could be used for the highest production of total phenolics and flavonoids as well as increasing the antioxidant activity through callus culture in this valuable plant of Iran.

Safflower (Carthamus tinctorius L.) belong to the Asteraceae family. It contains flavonoids such as contains kinocalcone pigments and these compounds shown to exhibit medicinal properties. These pigments are abundantly found in flower of this plant, but it has been seen that the roots of this plant have been able to produce these pigments in vitro. One of the ways to increase the production of secondary metabolites in tissue culture is to use different elicitors. In this study, jujube fruit extract and salicylic acid were used as an elicitor. Grown roots were first cultured in liquid Murashige and Skoog (MS) medium for mass production, in static condition. The roots were then sub-cultured with jujube fruit extract (0, 0.01, 0.05, 0.1, 0.5 and 1%) and salicylic acid (0, 500 μm). After 20 days of culture the growth was determined and the yellow pigments of root and medium were measured by spectrophotometer and the results showed that jujube fruit extract have protected root tissues against lipid peroxidation and this fact have triggered their growth. In this condition there was an increase in yellow pigments but these pigments were not released in the culture medium. Conversely, the SA treatment that further increases the production of pigments affected the integrity of cell membranes which lead to a fall of growth and a release of pigments in the culture medium.

In the drought conditions of the last few decades, the use of novel scientific methods to increase the growth and production of effective substances of the medicinal and aromatic plants has been essential. This study was done to investigate the effect of foliar application of salicylic acid and proline on the growth traits and essential oil content of Dracocephalum kotschyi Boiss. (Lamiaceae family) under water deficit conditions at the Research Farm of the Research Center of Agricultural and Natural Resources of Chaharmahal va Bakhtiari Province, Iran during the two crop years of 2017-2019. The experiment was performed as a factorial in a CRBD with three replications. Experimental factors included irrigation treatment at two levels of normal irrigation (non-stress, irrigation after draining 30% of F.C.) and deficit irrigation regime (irrigation after draining 50% of F.C.), and three levels of foliar application (control, salicylic acid 1 mM, and proline 1 mM). The essential oil from the aerial parts of the herb at early flowering stage was extracted by water distillation. According to the results, the highest content of chlorophyll a, b, and total (0.96, 0.45, and 1.39 mg/g, respectively) were observed in water deficit irrigation treatment. Also, application of water deficit stress increased the proline content by 70% compared to the control while it did not show a significant effect on the morphological traits of plant height, stem diameter, and plant dry weight. Salicylic acid as a defense factor reduced the negative effects of deficit irrigation conditions on the essential oil, proline, and chlorophylls a, b, and total contents. The highest and lowest contents of essential oils were obtained in foliar-application of proline (1.12 mL/100 g dry matter) and control (0.84 mL/100 g dry matter), respectively. In conclusion, the foliar-spraying of salicylic acid in conditions of deficit irrigation is recommended to reduce the negative effects of stress and increase the content of D. kotschyi essential oil.

Important monoterpenes such as camphor and fenchol are components of lavender (Lavandula angustifolia) essential oil. Monoterpene synthases are suitable target genes for metabolic engineering in Lavender. This study was performed to analyze the expression and induction of the two key genes (borneol synthase and fenchol synthase) involved in monoterpenes biosynthetic pathway in lavender after elicitation by methyl jasmonate and salicylic acid. First, plants in the pre-flowering and post-flowering stages were treated separately by methyl jasmonate and salicylic acid, each at a concentration of 1 mM. Then, plant leaves were harvested 0 (control), 24, 48 and 72 hours after treatments for gene expression analysis. The results showed that the expression of these genes was affected by salicylic acid and methyl jasmonate treatment. In general, the expression of both genes in the pre-flowering stage was higher than that of post-flowering. Moreover, the expression of borneol synthase was more affected by methyl jasmonate, so that its expression trend was completely increased up to 72 hours. Given the increased expression of borneol synthase and fenchol synthase in plants treated with salicylic acid, and methyl jasmonate it could be expected that the content of valuable monoterpenes such as camphor and fenchol increase in lavender.

In this study, the effect of exogenpous Azelaic acid and potassium phosphite on some antioxidant enzymes activity, lignin synthesis and metabolic pathways were investigated in Eryngium caucasicum. This experiment was performed in a completely randomized design in controlled consitions. Plants at the three-leaf stage were treated with potassium phosphite (2 g/L) and azelaic acid (1 mM) by spraying method. Results showed that Azelaic acid treatment led to a significant increase in the activity of SOD, POD and PAL enzymes, while potassium phosphite caused a remarkable increase in CAT and PAL enzymes but a decrease POD and SOD enzymes activity. Also, metabolic ouputs through GC-MS technique showed that the treatments had different effects on accumulation of some metabolites for example, the level of Phytol increased sharply under the influence of Azelaic acid treatment, while exogenous potassium phosphite increased n-Hexadecanoic acid and Linoelaidic acid. Metabolic cycles can be engineered with the precise use of these materials, which, in turn, can lead to the accumulation of a specific group of secondary metabolites.

The secondary metabolites of plants have been considered due to their diversity and roles in plants and human health. Grapevine is one of the plants that have secondary compounds with medicinal properties. such compounds include resveratrol which is a phenolic compound from the stilbenoid group. In order to investigate the resveratrol production under the effect of an elicitor, a CRD design with four replications using Soltani cultivar was done.

 The salicylic acid (SA) was used as an elicitor with variable concentrations including 0, 10-4, 10-5, 10-6 and was introduced into MS medium without hormones to examine it`s stress effects. At the molecular level, the effect of SA on the expression of stilbene-synthase gene was evaluated by semi-quantitative RT-PCR. In the biochemical experiment, the rate of resveratrol production was measured by HPLC.

 Stilbene-synthase expression analysis showed that SA with a concentration of 10-4 M had a positive and incremental effect on gene expression and showed a 35.48% of increase compared to the control state, and also the concentration of 10-5 M increased the gene expression 5.65% in relation with control state. In the biochemical experiment, increasing in production of resveratrol was observed in 10-4 M treatment compared to the control treatment (6.1 µg) and 10-5 M treatment (3.25 µg) did not show a significant difference with the control sample.

 SA as an elicitor and stimulant of resveratrol production could enhance the expression of stilbene-synthase gene followed by enhancing the medicinal properties of the Vitis plant.

The purpose of this investigation was to induce callus and produce cell suspension from the well-known medicinal plant Nigella sativa (Black seed). Subsequently, the effects of salicylic acid and methyl jasmonate elicitors were investigated on their antioxidant content and potency.

Callus was prepared from the cotyledonary leaves of the plant. Then, cell suspension culture was established using appropriate callus. The cells were treated with salicylic acid and methyl jasmonate elicitors and the content of total phenol and carotenoids was measured. Antioxidant potency was measured by the FRAP method.

The results showed that the treatments had no significant effect on the fresh weight of callus but the dry weight of callus was significantly reduced by treatment with salicylic acid. The highest amount of total phenol was observed in callus culture and salicylic acid-treated cell suspension. Treatment of cell suspension with both elicitors significantly increased the amount of flavonoids. The treatments resulted in a significant increase in the antioxidant capacity of the cell suspension, which was less in the methyl jasmonate treatment.

According to the obtained results, it seems that in the cell suspension of N. sativa salicylic acid induces a greater response than methyl jasmonate, which leads to extra induction of antioxidant properties.

Teucrium polium, from Lamiaceae family, is a medicinal plant. Due to overexploitation, low distribution and habitat destruction, this plant, is facing extinction. Plant biotechnology and tissue culture is an alternative method for plant secondary metabolites production. The present study aimed to enhance the production of secondary metabolites and antioxidant capacity of Teucrium polium L. using methyl jasmonate and salicylic acid elicitors. Leaf explants from hydroponically cultured 4-month-old plants were inoculated on Murashige and Skoog medium (MS) containing 2, 4-dichlorofenoxy acetic acid (2, 4-D) in concentrations of 0, 0.5, 1, 1.5 mg/L alone or in combination with benzyl aminopurin (BAP) at, 0.5, 1, 1.5, 2 mg/L concentrations. According to the results, the best callus induction (100%) was achieved at MS medium containing 1.5 and 2 mg/L BAP. Calli obtained from this treatment were subsequently treated with Methyl Jasmonate or Salicylic Acid at 0, 50 and 100 μg/L concentrations. After 40 days, the content of phenolics, flavonoid compounds and total antioxidant capacity were evaluated in a completely randomized design with three replications. Based on biochemical assays, the greatest total phenol content, flavonoids and total antioxidant capacity belong to calli treated with 100 μg/L acid salicylic (SA) and after that to cali treated with 50 μg/L methyl jasmonate(MeJa), while the difference between them was significant. The results of means comparison showed applying 100 μg/L SA on calli in medium with 1.5 mg/L BAP had the greatest effect on total flavonoid content. Therefore, the use of appropriate concentrations of these elicitors can play an effective role in enhancing the medicinal compounds in Teucrium polium.

The aim of this study was to evaluate the effect of elicitors on antioxidant properties and mycelial secondary metabolites of Arthrinium arundinis, Lichen symbiont, and Hyphodontia paradoxa and Stereum hirsutum hosted by Betula pendula . In the summer of 2016 preliminary sampling was performed from tree barks of Siah-Marzkouh, Golestan province, from an altitude of 2400 m above sea level. Then, fungal purification was achieved. In 2018, biennial mycelial reserves were used to investigate changes in secondary compounds. The following treatments were applied as elicitor: sodium nitrate, nanofibers cellulose and magnesium sulphate. Initial evaluation of triterpenoids was performed by HPLC using standard betulin and betulinic acid, and LC-MS was used to confirm the corresponding peak as triterpenoid. Antioxidant properties in mycelia of these fungi were studied by DPPH method. Based on the results, the highest peak of triterpenoids which are derivatives of betulin was in H. paradoxa treated by nanofibers cellulose, while in S. hirsutum it was by sodium nitrate (6.5 and 6.37 times in comparison to control, respectively). In A. arundinis, elicitors had no effect on triterpenoids amount and significantly reduced it. The antioxidant activity of H. paradoxa in the control treatment was 83.1% and the induction of elicitors had the opposite effect on this activity. The antioxidant activity of A. arundinis decreased from 82.05 to 87.12% with magnesium sulfate elicitor, meanwhile by adding sodium nitrate to the medium it increased from 24.62 to 86.04%.

St. John’s wort is a traditional herbal medicine used to treat depression and wound healing. Natural resource dependency and traditional cultivation methods often require months and years of time to reach medicinal plants. Establishing a hairy root suspension culture system can accelerate proliferation on a large scale, improve breeding and protect the species, but optimization and production on a large scale require an increase in the biomass and secondary metabolites of the root. In this study, the effect of different concentrations of myo-inositol (50, 75, 100, 125, 150, 175, 200, 225, 250, and 275 mg / l) were evaluated on biomass, phenol, flavonoid, DPPH activity and secondary metabolites in St. John's wort adventitious root in Agricultural Biotechnology Research Institute-Central Region of Iran. The results showed that 125 and 150 mg L-1 myo-inositol concentration had the highest dry weight, growth rate and growth ratio. The concentrations of 100 and 250 mg L-1 myo-inositol have been showed the highest and lowest amount of hypericin and pseudohypercin, respectively. From the viewpoint of production of hyperforin, the treatment with 100 mg L-1 myo-inositol was highest and the concentration of 125 mg L-1 had the least effect on the level of hyperforin in St. John's wort adventitious root culture. There was a significant difference between treatments in terms of phenol and flavonoid content, so the concentration of 75 and 225 mg L-1 and 75 mg L-1 myo-inositol had the highest amount of phenol and flavonoids. The DPPH activity changes were different between treatments, and the 50 mg L-1 showed the lowest amount of DPPH activity. However, the DPPH activity was highest in treatment with 75 mg L-1 myo-inositol concentration. Since the potential for stimulating secondary metabolites varies among cultures, elicitors, conditions for applying different treatments and other parameters, further research is needed to optimize better and more efficient guidelines.

Medicinal plants of the Asteraceae family are important genetic resources due to their high echological flexibility in diverse climates,. Yarrow (Achillea millefolium subsp. millefolium) is a self-pollinated plant belongs to the Asteraceae which produce a wide varieties of plant secondary metabolites such as terpenoids and phenylpropanoids. In the present work, gene expression patterns of genes involved in the biosynthetic pathways of terpens and phenylpropanoids were studied to understand the regulatory mechanism behind them. 1-deoxy-D-xylose-5-phosphate reductoisomerase (DXR) and geranyldiphosphate synthase (GPPS) are important genes in the biosynthesis of monoterpenes in the 2-C-methylerythritol-4-phosphate (MEP) pathway. Phenylalanine ammonia lyase (PAL) and chalcone synthase (CHS) genes are important in the biosynthesis of phenylpropanoids. In the present study, semi quantitative RT-PCR of these genes was carried out in different developmental stages, also in response to methyl jasmonate treatment in leaves and flowers. Results showed that expression of these genes were higher in flowers and methyl jasmonate treated plants, also the expression of these genes affected by developmental stages of leaves but with different intensity.

Plant responses to elicitors are the result of a series of highly modulated consecutive changes in hormones or reactive oxygen species (ROS). In the present study, we examined growth index, chlorophylls and carotenoid content, H2O2 content, membrane lipid peroxidation, antioxidant enzymes (CAT, GPX, APX and SOD) activity and proline content in M. officinalis shoots culture that induced through the use of an elicitor, ABA. Mediums of M. officinalis were fed by different concentration of ABA (0, 5, 25, 50 and 100 µM) and 7 and 14 day after elicitation, biochemical and physiological parameters were measured in shoot cultures. Growth index of the treated samples decreased in all concentration of ABA compared to control. Content of chlorophyll a, b and total chlorophyll decreased in all concentrations of ABA compared to control. Content of carotenoid at 25 and 100 µM concentrations of ABA increased compared to control. ABA elicitor increased the amount of H2O2 at all concentration of ABA compared to control. Among the measured antioxidant enzymes APX enzyme and SOD enzyme increased at all concentrations of ABA. Content of lipid peroxidation increased only at 100 µM concentration of ABA compared to control. Content of proline increased at all concentration except at 5 µM concentration of ABA compared to control. ABA as a transmitter molecule seems to play an important role in the production of hydrogen peroxide and the production of antioxidant defense proteins such as catalase and peroxidases in shoot cultures of M. officinalis.

Chlorella is valuable alga that applied for medicine, industry and food. For this reason increase of biomass and its metabolites is important. Our aim was obtain the best material or phytohormone combinations for increase of biomass and valuable metabolites contents of Chlorella sorokiniana. In this study Chlorella sorokiniana was cultured at modified Bold Basal Medium (BBM). Different proportions of plant hormones naphthalene acetic acid (NAA), indolebutyric acid (IBA) and kinetin (Kin), nitrate and phosphate and thiamine pyrophosphate were added to medium. At majority treatments of  NAA+Kin,   dry weight, photosynthetic pigments and protein contents increased compared to control. At treatment NAA (10mg.L-1) + Kin (1mg.L-1), these parameters significantly enhanced   compared to  control.  At treatment of IBA+ Kin, dry weight and metabolites had not significant difference compared to control. Thiamine pyrophosphate did not significant effect on growth. But increase of nitrate with phosphate was caused enhancement of dry weight photosynthetic pigments and protein contents compared to control. The highest proportion of dry weight, metabolites and protein contents were observed at medium were supplemented with higher amount of nitrate and phosphate, then NAA+ Kin treatment compared to control. Increase of nitrate and phosphate was the best treatment for enhancement of algae growth.

In order to investigate the effect of salicylic acid, potassium silicate and fungal Elicitor in calendula under salinity stress conditions, a factorial arrangement in a randomized design with three levels of salinity (0-300600ppm) and 3 levels of salicylic acid, potassium silicate and fungal Elicitor (300-600-900 ppm) in 3 replicates. The highest amount ofH2O2was observed in potassium silicate treatment with a concentration of 300 ppm and a value of 68.87 nmol / g fresh weight. The highest amount of catalase enzyme in Salinity SA was obtained 600 ppm with a value of 0.0584 mg / d of protein per minute. The average number of leaves in potassium silicate treatment was higher than other treatments. The lowest root diameter in a substrate with 600 ppm salinity was observed at a concentration of 300 ppm in penicillium fungicidal oligoetherium with a value of 0.61 mM. In the concentration of 900 ppm in non-saline bed, the highest root diameter was observed with a value of 1. 08 mm

Hemp (Cannabis sativa L.) is an annual dioecious plant of the Cannabiaceae family that produces various secondary metabolites and has numerous dietary fiber and pharmaceutical properties and nutritional value. Dela-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are two of the important cannabinoids in hemp. One of the basic steps for the increased production of metabolites is to study the contents of important metabolites and the effects various elicitors have on their production. Moreover¡ employing simple and convenient methods in the application of safe and inexpensive elicitors with the purpose of increasing the content of a specific metabolite is a commercial and valuable treatment. The main purpose of this research was to confirm the role played by ascorbic acid (a small¡ inexpensive¡ and safe biomolecules) as an elicitor in stimulating expression of genes involved in the biosynthetic pathways of cannabinoids in the valuable hemp plant¡ which leads to increased production of the key metabolites THC and CBD. Results showed a significant increase in the expression of the THCAS¡CBDAS¡ PT¡ and OLS genes as the key genes in the biosynthetic pathways of cannabinoids in hemp. Based on biochemical measurements¡ gene expression patterns matched metabolite production. The abiotic elicitor ascorbic acid significantly increased production of the two main cannabinoids THC and CBD¡ the two active ingredients that are used in drug manufacturing.

Aim: The effect of chitosan (low molecular weight) as elicitor was evaluated on silymarin production and biochemical factors in hairy root cultures of Silybum marianum.
Material and Different concentrations of chitosan (0, 5, 10, 20 and 30 mg/50 ml of culture media) was added to hairy root cultures of S. marianum (30 days) and sampling were carried out after 12, 24, 48, 72, 96 and 120 hours. The silymarin level, activity of guaiacol peroxidase and ascorbate peroxidase as well as concentration of H2O2 were determined in the samples.
The results indicated that the highest dry weight was in cultures treated with 10 mg /50 ml culture chitosan after 48 and 96 h. Silymarin production was significantly increased from 0.37 in control to 1.19 mg g-1 dry weight in the treated samples, at which the increased level was 1.4-fold higher than the control. Guaiacol peroxidase was activated by chitosan and reaching a pick after 120 h (21.86 ∆OD g-1FW min-1) which was 2.2 fold higher than the control. The ascorbate peroxidase activity kept increasing until 96 h after elicitation (5.14 ∆ODg-1FW).
The results showed that the silymarin production has been promoted by chitosan (low molecular weight). Increased of enzymes activity occurs as a result of free radical elimination and represents a reaction to chitosan as a stress factor.