Bijan Soltanian; Parviz Rezvani Moghaddam; Javad Asili
Abstract
Introduction: Nowadays the demand for medicinal plants is increasing in the pharmaceutical industries. Echinacea spp. is an herbaceous, perennial plant containing valuable substances which belong to different chemical groups, most notably phenolic compounds. Echinacea is the most well-known and most ...
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Introduction: Nowadays the demand for medicinal plants is increasing in the pharmaceutical industries. Echinacea spp. is an herbaceous, perennial plant containing valuable substances which belong to different chemical groups, most notably phenolic compounds. Echinacea is the most well-known and most important treatment for the immune system and protects against cough, cold and fever. Drought stress can be a major factor in increasing the content of secondary metabolites in many medicinal plants. Organic fertilizers are known to be one of the fertility factors for soil and plant nutrition due to the impacts on the physical, chemical and biological properties of soil. The purpose of this study was to investigate the response of yield and phenolic compounds as the most important group of active compounds in Echinacea in response to different levels of water stress, chemical and organic fertilizer management and their interactions. Materials and Methods: This experiment was carried out during 2016 and 2017 years at the experimental Field of Ferdowsi University of Mashhad, located at 10 km East of Mashhad. The split plot based on factorial design was implemented in 3 Replications. The studied factors in this experiment in the main plot were water stress at three levels, including1- Non-Water stress (6000 m3.ha-1), 2- Moderate Water Stress (4500 m3.ha-1), 3- Severe Water stress (3000 m3.ha-1).In sub plots, fertilization treatments applied in eight levels, including, 1- NPK fertilizer (500 kg.ha-1) ; 2-Humic acid (20 L.ha-1); 3-Vermicompost (6000 kg.ha-1); 4-Humic acid+NPK (20 L.ha-1+500 kg.ha-1); 5. Vermicompost+NPK (3000 kg.ha-1+250 kg.ha-1); 6-vermicompost+humic acid (3000 kg.ha-1+20 L.ha-1); 7. Vermicompost+Humic acid+NPK (3000 kg.ha-1+20 L.ha-1+250 kg.ha-1) and 8.control. The amount of irrigation needed at each turn was calculated by NETWAT software. In combined treatments, half of the NPK fertilizer which used in the pure treatment was replaced with the equivalent amount of vermicompost. Constant amount of liquid humic acid was applied at the same time with vermicompost and NPK in rosette leave developing and before stem-elongation phase. The total amount of phenolic compounds in the sample was evaluated by the Folin-Ciocalteu method. Data were analyzed with MSTAT-C statistic software and means compared by Duncan Multiple Range Test. Results and Discussion: The most amounts of stem dry matter, flower dry matter and biomass were observed at vermicompost and non-stress treatment and the least amount of them was obtained from control and severe water stress condition. The highest amounts of leaf and root dry weight were obtained under vermicompost+humic acid and moderate water stress treatments and the least amount of leaf dry weight was observed at control and severe water stress treatments. At the same time with the increase of water stress, the impact of organic fertilizers on leaf dry weight decreased, however the application of organic fertilizers increased the leaf dry weight even under severe stress conditions. Maximum seed yield was observed under vermicompost+humic acid+NPK and NPK treatments with severe water stress condition. With increase in the stress level, root to shoot ratio was increased and the maximum amount of that was obtained in control treatment under severe water stress condition and the minimum amount of that was obtained at vermicompost and non-stress treatment. The application of vermicompost and humic acid increased root to shoot ratio in severe stress conditions and it were effective in developing root systems in these conditions. Maximum amounts of phenolic compounds were observed under humic acid+vermicompost treatment with severe stress condition and minimum of these compounds were obtained under humic acid treatment at no-stress. Conclusion: The response of aerial parts of plant was associated with a decrease in irrigation levels, however this trend was reversed in underground sections. Thus, the maximum amount of root dry weight, root to shoot ratio and root phenolic compounds were observed in severe stress treatment. The highest amount of Phenolic compounds of the root, the ultimate goal of this plant, were observed under humic acid+vermicompost combination treatments. Therefore the production of this plant in terms of supplying 50% of the required moisture content (is equivalent to 300 mm of irrigation during the one-year growth period) and the use of fertilizer treatments containing humic acid and vermicompost compounds is recommended.
Gholamhossein Davarynejad; Seyedeh Faezeh Taghizadeh; Javad Asili
Abstract
Introduction: Phenolic compounds have an ability to scavenge free radicals and cause the balance of reactive oxygen species (ROS) in our body. This balance prevents atherosclerosis, coronary heart and cancer diseases. Butylated hydroxyl toluene (BHT) is a well-known synthetic antioxidant, which is restricted ...
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Introduction: Phenolic compounds have an ability to scavenge free radicals and cause the balance of reactive oxygen species (ROS) in our body. This balance prevents atherosclerosis, coronary heart and cancer diseases. Butylated hydroxyl toluene (BHT) is a well-known synthetic antioxidant, which is restricted to be used due to its probable toxic effects. Therefore, replacement of synthetic antioxidants with plant materials with high amounts of antioxidant activity, which protect the body from free radicals and many diseases caused by lipid peroxidation, is an appropriate option. ZiziphusjujubaMiller is one of the forty species belonging to Rhamnaceae family, which produces a great deal of industrial raw materials for horticultural, ornamental, food, and pharmaceutical industries. Antioxidants can be extracted by various solvents and extraction methods. Solvent extraction is the most common method used for separating natural antioxidants. Solvent properties undoubtedly play a key role in the extraction of antioxidative compounds. The type and yield of antioxidant extracted have been found to vary as affected by the solvent properties such as polarity, viscosity and vapor pressure. Therefore, it is difficult to develop a unified standard method for the extraction of antioxidants from all plant materials.
Materials and Methods:
Plant materials Fresh fruits were collected from Birjand, Iran, in late summer 2014. The samples were air dried under the shade at room temperature. Dried fruits were ground by using a mortar and pestle and were separately extracted by distilled water and organic solvents such as methanol, ethanol and acetone (50%, 90% and100% (v/v)). After filtering through the Whatman paper #3 and removing the solvents (using a rotary evaporator (BUCHI V-850)) and water (using a freeze dryer, (OPERON, FDB-5503, Korea)), the dried extracts were stored in refrigerator for further analysis.
Determination of Total Phenolic Content (TPC) Samples were measured for TPCs colorimetrically using the Folin-Ciocalteu method with modification. Absorbance was read at 725 nm against blank using UV-Visible spectrophotometer (Cecil. UK.). A calibration curve was prepared using a standard solution of Gallic acid (0.2-1mg/ml). Results were expressed as mg Gallic acid/g dry extract (mg GA/g DE).
Determination of Total Flavonoid Content (TFC). TFC was determined using the method of Huang et al. (13) with minor modifications. Absorption was measured at 430 nm using UV-VIS spectrophotometer (Cecil. UK.). TFC was determined using a standard curve with quercetin as the standard, and expressed as mg of quercetin equivalents (CE)/g dry extract (mg QE/g DE).
Determination of Total Anthocyanin Content (TAC). TAC was measured using a spectrophotometric differential pH method. Its absorbance was read at 510 and 700nm. Results were expressed as milligrams of cyanidin-3-glucoside (CY.) equivalents per g of dry extract.
Determination of Total Tannin Content. For determination of tannins in the sample extracts, vanillin–HCl method was used. The absorbance was read at 500 nm using UV–vis spectrophotometer. The content of tannins in the sample was expressed as mgcatechine equivalent (CE)/100g sample.
Determination of Antioxidant Activity. Antioxidant activity of the samples was determined using DPPH (2, 2-diphenyl-1-pic-rylhydrazyl) radical scavenging activity and ferric reducing antioxidant power (FRAP). In the presence of antioxidant, FRAP assay reduced Fe3+-TPTZ (2, 4, 6-tris (2-pyridyl)-5-triazine) complex to Fe2+ - TPTZ at low pH. The absorbance of the mixture was measured by using spectrophotometric ally at 595 nm. The effect of antioxidant on DPPH radical was thought to be due to their hydrogen donating ability or radical scavenging activity. DPPH assay expressed as IC50 and percentage inhibition. Lower IC50 value indicates higher antioxidant activity.
Results and Discussion: Efficiency of different solvent extractions depends on the matrix of plant materials as well as the type of extractable compounds. The correct selection of solvent can improve the extraction yield of antioxidants from plants matrices considerably. For this reason, in the present study, some selected types of solvent showed different results. For extraction of total phenol and flavonoid compound, acetone 50% was the best yield. In methanolic extract (50, 100%), the highest amounts of anthocyanin and total tannin were reported. In all extracts, water had the least efficiency in comparison with other solvents. High correlation was observed in total phenolic content and antioxidant activity which was determined by DPPH and FRAP assay. Acetone 50% was the most potent for scavenging free radicals and reducing a ferric-tripyridyltriazine, Fe (III)-TPTZ, complex to ferrous, Fe (II) in all extracts.
Conclusions: The results of the present study indicated that polarity, selectivity, viscosity, and vapor pressure are important physicochemical properties that should be considered when selecting a suitable solvent for the extraction of bioactive compounds from plant materials.
Masumeh Modarres; Mehrdad Lahouti; Ali Ganjeali; Javad Asili
Abstract
Salvia leriifolia (Lamiaceae) is endemic of Khorasan and Semnan province and an endangered plant. Poor seed germination of this plant has a serious problem with the high production. The first step to improve this precious plant is to produce sterile plantlets in order to prepare explants of appropriate ...
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Salvia leriifolia (Lamiaceae) is endemic of Khorasan and Semnan province and an endangered plant. Poor seed germination of this plant has a serious problem with the high production. The first step to improve this precious plant is to produce sterile plantlets in order to prepare explants of appropriate vigor. In this study,in vitro culture of Salvia leriifolia zygotic embryo was performed through a factorial experiment in the form of completely random design including culture medium, BAP and NAA. The results showed that, MS and 1/2MS media appeared to be more efficient than B5 medium and significant differences were observed. Efficient concentrations of BAP and NAA were 1mgL-1 and had a significant effect in growth and development of embryos. The seedlings were obtained 10 days after planting. Based on these results, the best choice for quick access to strong seedlings, seedling growth and development of embryos is MS and 1/2MS media supplemented with 1mgL-1 BAP and NAA.
