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Статья научная
Impacts of various concentrations of polyetylenglycol 6000 (PEG 6000) (0, -9, -11, -13 and -15 bar) and hydro priming on Mountain Rye (secale montanum) germination characteristic and enzyme activity were evaluated under drought stress in the seed laboratory of Natural Resources Faculty, University of Tehran, Karaj, Iran. Analyze of variance for hydro priming showed that temperature × time of priming interaction was significantly for germination percentage (GP), normal seedling percentage (NSP), coefficient of velocity of germination (CVG), seedling vigor index (SVI), coefficient of allometry (AC) and seedling length (SL) under drought stress and for osmo priming showed that Concentration of PEG × Temperature × Time of priming interaction was significantly for all traits under drought stress. Results of interaction effects for hydro priming showed that the highest GP (53%) and NSP (23.5%) were attained from hydro priming for 16h at 15◦C and the highest CVG (0.21) and AC (0.49) were attained from hydro priming for 8h at 10◦C, also hydro priming for 8h at 15◦C increased SL (3.15) as compared to the unprimed. Osmo priming with concentration of -15 bar PEG for 24h at 15◦C increased GP (80.5 %), GI (17.9), NSP (45 %), SVI (257.85) and SL (5.73 cm) and decreased MTG as compared to the unprimed and other treatments of osmo priming. The highest CVG was attained from concentration of -9 bar PEG for 24h at 10◦C. the highest AC was attained from concentration of -9 bar PEG for 12h at 15◦C. Also osmo and hydro priming increased catalase (CAT) and ascorbate peroxidase (APX) as compared to the unprimed.
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Osmotic adjustment in wheat flag leaf in relation to flag leaf area and grain yield per plant
Статья научная
Background Salinity stress causes ion toxicity and osmotic imbalances, leading to oxidative stress in plants. Antioxidants are considered ameliorators of saline stress and could develop salinity tolerance in crop plants. To ascertain the role of antioxidants in inducing osmotic adjustment in salt stressed wheat flag leaf in terms of compatible solutes accumulation, water relations parameters and osmotic adjustment as well as flag leaf area and grain yield per plant, in addition, flag leaf anatomy were examined. Results Salt stress up to 11.5 dSm-1 causes a significant reduction in water potential, osmotic potential, as well as relative water content, and water content. On the other hand, turgor potential and osmotic adjustment were significantly increased due to inducing increasing the higher accumulation of compatible osmolytes which leads to decreasing flag leaf area and grain yield per plant. Application of both antioxidants, in particular, ascorbic acid increased significantly flag leaf area, and grain yield per plant due to osmotic adjustment and maintaining leaf turgor potential as a consequence of increasing leaf water potential, water content and relative water content as compared to control plants. On the other hand, application of both antioxidants under all salinity levels, ify the harmful effects of salinity on flag leaf area and grain yield per plant due to increasing osmolyte accumulation, maintaining turgor potential and osmotic adjustment. Anatomically, increasing salinity levels decreased thickness of leaf blade at midrib region, thickness of mesophyll tissue, tangential dimension of midrib vascular bundle, thickness of upper and lowerepidermis, thickness of big motor cell, and tangential dimension of big xylem vessel. Treatment with either ascorbic acid or tocopherol at 100 mg/L and their interactions with salinity increased all the above mentioned parameters in both nonsalinized and salinized plants. Ascorbic acid is the most effective in this concern. Conclusion In conclusion, wheat plants responded to an increased ion influx in their cells by increasing the osmolytes synthesis and accumulation under salt stress, which further increased with antioxidants treatment and helped in maintaining the osmotic balance.
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Статья научная
Pranayama aims by carrying the involuntary functions of the respiratory mechanism within human control. The term pranayama has comprised by two words: Prana + Ayama. Prana is the vital force and energy which permeates the whole universe. Prana is novel subtle than air and can be defined as the energy essence that is within everything in the universe. In present time emphasis is on the beneficial effects of Pranayam in various diseases i.e. diabetes mellitus, hypertension, obesity and depression by application of specific exercise like walking in a planned way. This was also explained and proved by American college of sport medicine. In Ayurveda various breathing exercise and yogic practices have been mentioned. The respiratory System, central nervous system and cardiovascular system are the important systems which are mostly affected by Pranayam and other physical activities. Breathing exercise is highly effective in endorsement of respiratory system and management of diseases related to respiratory system.
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Статья научная
Late embryogenesis abundant (LEA) proteins are speculated to protect against water stress deficit in plants. An over expression system for mungbean late embryogenesis abundant protein, emv2 was constructed in a pET29a vector, designated pET-emv2 which is responsible for higher expression under the transcriptional/translational control of T7/lac promoter incorporated in the Escherichia coli BL21 (DE3).Induction protocol was optimized for pET recombinants harboring the target gene. Overexpressed EMV2 protein was purified to homogeneity and the protein profile monitored by SDS-PAGE.
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Статья научная
Glutathione-S-transferase is one of the important enzyme systems that plays vital role in decomposition of lipid hydro-peroxides formed due to oxidative stress. In the present study GST activity increased in the lymphocytes treated with increasing concentration of H2O2, and decrease in the levels of GSH was observed. For similar treatment conditions LDH activity and MDA levels increased significantly leading to decrease in the cell viability. Treatment of lymphocytes with the root extract of Phlogacanthus tubiflorus (PTE) resulted in dose dependent decline in the GST activity and rise in GSH levels. LDH activity and MDA levels also declined that led to the increase of cell viability. Lymphocytes pre-treated with the PTE followed by H2O2 (0.1 and 1%) treatment, decline in the activity of GST and increase in GSH levels was observed. Also we have observed decline in the activity of LDH and MDA levels in the lymphocytes for both 0.1 and 1% of H2O2 though the magnitude of change was higher in the lymphocytes pre-treated with the PTE followed with 1% of H2O2 treatment. Significant increase in the cell viability for similar conditions was also observed. These findings suggest protective function of the root extracts might be through modulation of GST activity and levels of GSH and might find application in Chemomodulation in future.
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Статья научная
Increasing evidences indicate involvement of free radicals in the pathogenesis of benign and malignant breast diseases. Free radicals are highly reactive molecules and react with non-radicals in chain reaction leading to formation of new free radicals. If the defense mechanism of body fails to combat them, these free radicals pose a threat of injuring tissues by reacting with cell lipids. Lipids in the cell membrane undergo degradation to form hydroperoxides, which decompose to form a variety of products including malondialdehyde (MDA). MDA therefore was used as a marker to assess oxidative damage of cells and tissues. The aim of the present study was to assess the status of oxidative stress in the patients of benign and malignant breast diseases. Study has been made on the blood samples of 25 cases of benign breast disease and on an equal number of breast carcinoma patients. 20 healthy subjects were taken as the control cases. Mean MDA levels were significantly raised with depletion of antioxidant activity in all the patients in comparison to their control group suggesting the role of oxidative damage in the aetiopathogenesis of disease.
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Статья научная
Objective: To access the oxidative stress status by quantification of byproducts generated during lipid peroxidation and DNA breakdown products generated during DNA damage in the blood serum of multiple myeloma and lymphoma patients. Material & Methods: Case control study comprised of 40 patients of multiple myeloma and 20 patients of lymphoma along with 20 age and sex-matched healthy subjects as controls. Levels of Malondialdehyde and 8-hydroxy-2-deoxy-Guanosine were measured to study the oxidative stress status in the study subjects. Results: The level of markers of DNA damage and lipid peroxidation were found to be raised significantly in the study subjects in comparison to healthy controls. The results indicate oxidative stress and DNA damage activity increase progressively with the progression of disease. Conclusion: Oxidative stress causes DNA damage and Lipid peroxidation which results in the formation of DNA adducts leading to mutations thereby indicate the role of oxidative stress in the pathogenesis of multiple myeloma and lymphoma.
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Статья научная
The interactive effects 0.5 mM indole acetic acid or 0.1 mM of salicylic acid as shoot spraying on NaCl wheat stressed plant organs (spike, shoot and root) grown in pot experiment under different salinity levels (0, 50, 100, 150 and 200 mM NaCl) were studied. The antioxidant enzymes as catalase, peroxidase and ascorbate peroxidase, photosynthetic pigments, reducing sugar, proteins, amino acids, and proline contents in spike, shoot and root of salinity stressed plants were the most affected parameters specially at high salinity levels (150-200 mM NaCl).Treatments with 0.5 mM indole acetic acid or 0.1 mM of salicylic acid as shoot spraying on NaCl wheat stressed plant organs mitigated the harmful effect of NaCl. To conclude the phytohormone acetic acid or salicylic acid salt tolerance in stressed wheat by significantly catalase, peroxidase, and ascorbate peroxidase, increased photosynthetic pigments and the accumulation of nontoxic metabolites (sugars, proteins, amino acid and free proline) as a protective adaptation mechanismin different wheat organs. However, the magnitude of increase was more pronounced in salicylic acid treated plants than in indole acetic acid treated ones, and the spike was more accumulator organ of non toxic metabolites compared to shoot and root. salicylic acid and/or indole acetic acid treatments prevents the deleterious effects of salinity stressed wheat and could be adopted as a potential growth regulator or antioxidant to improve growth particularly under moderate NaCl salinity levels, wheat plant respond positively to SA foliar application than IAA application.
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Oxidative stress tolerance by calcium and histidine in two tomato cultivars under nickel stress
Статья научная
We investigated calcium (Ca) and L-histidine (His) interaction on nickel (Ni)-induced oxidative stress tolerance in two tomato (Solanum lycopersicum Mill.) cultivars including Cal-J N3 and Petoearly CH. CaCl 2 (0 and 300 µM) and L-histidine (0 and 300 µM) effects on the oxidative responses in these cultivars cultured were compared in the hydroponic media under Ni stress (NiSO 4; 0,150 and 300 µM). The activities of antioxidative enzymes including catalase (CAT), guaiacol peroxidase (GPX), ascorbate peroxidase (APX), superoxide dismutase (SOD) and total content of proteins, malondialdehyde (MDA), other aldehydes, H 2O 2, Ca 2+, Ni 2+, ascorbate (ASC), dehydroascorbate (DHA) and electrolytes leakage (EL) were determined. The obtained results indicated that the application of Ca and His generally reduced oxidative markers such as the contents of EL, H 2O 2, MDA and activity of CAT as well as the Ni 2+content of root and shoot organs under nickel toxicity, while application of Ni treatment without Ca+His increased these oxidative parameters and accumulation of Ni 2+, compared to the control. Applying Ni without Ca and His has resulted in reduction of GPX, APX and SOD activities as well as concentrations of root and shoot Ca 2+and ASC in the two mentioned cultivars. Application of Ca and His lead to the elevated contents of Ca 2+ and ASC, increased activities of GPX, APX and SOD as well as inhibition of Ni 2+ accumulation differently in both cultivars. Ca and His also alleviated the adverse effects of Ni stress on the selected investigated parameters especially in Petoearly CH cultivar. Thus, interaction of Ca and His appeared to improve adaptive responses to Ni stress leading to decreasing Ni-induced oxidative stress in the tomato plants. Therefore, our results suggest that Ca+His alleviated nickel-induced oxidative stress by uptake and inhibition of translocation of Ni 2+ plus Ni chelating mechanism improvement in the tomato cultivars.
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PCR based detection of insulin like protein from Dolichos lablab L
Статья научная
In the current research work, the genetic region corresponding to both alpha and beta chains of insulin like protein from Dolichos lablab L was identified using PCR. Earlier study by Venâncio et al. , (2003) has revealed that the amino acid sequence of alpha and beta chains of bovine insulin has significant similarity to amino acid sequence of insulin like protein from legume Vigna unguiculata (cowpea). Although the amino acid sequence was available for V. unguiculata , the corresponding DNA sequence was not available in the database. Considering the resemblance in protein sequence, primers were designed using nucleotide sequences of alpha and beta chains of bovine insulin and were used for amplification of these chains from V. unguiculata and D. lablab . Genomic DNA extraction was carried out by the conventional ethanol precipitation method followed by purification using preparative AGE. Standardization on PCR amplification of alpha and Beta chain of Insulin from D. lablab L...
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PPAR gamma agonists - plant compounds
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The nuclear receptor peroxisome proliferator activated receptor-gamma (PPARg) controls adipocyte differentiation, as well as lipid metabolism and insulin sensitivity. As a result, PPARg is a promising candidate gene for a variety of human diseases, such as obesity and type 2 diabetes. Hyperglycemia associated with the metabolic syndrome and type 2 diabetes is treated with agonists of the nuclear receptor PPARg. The PPARg agonists of the thiazolidinedione type, despite being effective in normalizing blood glucose levels, have serious side effects, making the discovery of novel ligands extremely important . Natural products have historically proven to be a promising source of structures for drug development, and recent research has focused on the PPARg-activating potential of a wide range of natural products derived from traditionally used medicinal plants or dietary sources. This review highlights recent studies that have advanced our understanding of this receptor's role in metabolism, with a focus on the effects of compounds in the plant
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Статья научная
This study was designed to evaluate the effect of drought stress and drought with defoliation on yield parameters of three sorghum varieties (Giza 15, Dorado and Hybrid 113). Also, the effect of these parental stress treatments on drought performance of progeny of the most drought tolerant variety was investigated. Application of drought stress in the vegetative stage non significantly affected panicles number, grain yield and harvest index of all cultivars. Drought stress in the reproductive stage of Giza 15 and Hybrid 113 cultivars caused a two fold increase in length of lateral branch and panicles number. However, grain yield and total panicles weight were significantly reduced in all cultivars due to this stress. Application of drought with defoliation in the vegetative stage reduced shoot and straw weights, and grain yield in sorghum in comparison with drought stress only. Protein-N and polysaccharides content were decreased in parent grains in response to water stress. The stress intensity index (SII) of progeny from drought- subjected parents was about 30-fold greater than SII of progeny from control parents. Further, SII of progeny from parents exposed to drought stress in the vegetative stage was higher than the SII of progeny from parents subjected to drought stress in the vegetative stage. A strong negative correlation appeared between the stress intensity index of the progeny and polysaccharides content of parent grains. Based on our research parental defoliation did not improve the drought resistance of sorghum progeny.
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Статья научная
Oxygen deficiency causes significant changes in plant metabolism related to the coordination of metabolic processes for stress adaptation. MicroRNAs provide regulation of target genes at the post-transcriptional level. The plant cell presents hypoxia-dependent microRNAs, including miR775A, whose quantity increases under these stress conditions. An electrophoretic study of total RNA samples from corn leaves under hypoxia has revealed the presence of two interfering complexes with miR775A at the 12th hour of the experiment. Sequencing and subsequent analysis of the nucleotide sequence of image 2 of the miR775A interfering complex with mRNA from corn leaves have showed a high degree of homology with the N-acyltransferase domain, and corresponded to a fragment of glycerol-3-phosphate acyltransferase mRNA. Inhibition of glycerol-3-phosphate acyltransferase in maize leaf cells under hypoxia can probably provide regulation of cellular fatty acid metabolism under the influence of a stress factor.
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Статья обзорная
Barley is one of the most important cereal crops grown worldwide. Spot blotch caused by the hemibiotrophic fungus Cochliobolus sativus , is a destructive disease of barley leading to significant yield losses globally. Barley plants have evolved complex and orchestrated defense mechanisms to protect themselves towards this disease. Therefore, understanding the molecular basis of barley - C. sativus interaction is crucial to efficiently breed for durable and long lasting resistance. A number of pathogenesis-related proteins (PRs) genes have been identified and studied. Overexpression of PR genes (chitinase, glucanase and thaumatin) individually or in combination has significantly uplifted the level of defense response in barley plants against C. sativus pathogen. However, the detailed comprehension of signaling pathways that regulates the expression of these PRs is critical for improving crop plants to the pathogen challenge, which is the future theme of plant stress biology. Here, we summarize the advances in studies on interactions between barley and the C. sativus pathogen through these PR genes, by reviewing a comprehensive body of research on their interaction and the advances recently made
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Статья научная
The objective of this research was to investigate the effect of short-term heat (2 h., +400C) and cold (2 h., +20C) stresses on accumulation and distribution of cytokinin (CK) in 7 and 14-day-old seedlings of the frost resistant Triticum aestivum L. cultivar Volodarka. A high performance liquid chromatography method has been used to provide a qualitative and quantitative analysis of hormones in leaves and roots. It was shown that in the early stages of growth (7 days) after exposure to high temperature the total content of cytokinin in roots increased 1,6 and in leaves in 2,55 times. The most pronounced changes were registered for trans -zeatin ( t -Z) and izopenteniladenozin (iPa) in roots and for zeatinriboside (ZR), izopenteniladenin (iP) and iPa in leaves. After cold stress the total content of hormone in roots increased but decreased in leaves. ZR and iPa were not identified in the leaves. The total level of CK in 14-day-old seedlings as compared to 7-day-old ones under control conditions decreased from 685,3 to 158,3 in roots and from 396,8 to 368,4 ng / g fresh weight in leaves. After cold stress the total content of CK in the roots decreased to 99,9 and in the leaves - to 195,8 ng/g of wet weight. Trans -zeatin was actively accumulated in leaves, ZR - in the roots. After heat stress the total content of CK in roots increased to 316,3, whereas in leaves decreased to 184,6 ng / g fresh weight. Roots actively accumulated cis -zeatin ( c -Z) and iPA, leaves - iP and iPa. Changes in the accumulation and distribution of CK depended both on the organs and the age of seedlings, and the type of stress and correlated with frost resistance of the cultivar Volodarka.
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Performance of sesbania-sunflower under different cropping systems using 15N and 13C
Статья научная
A field experiment on sesbania (ses) and sunflower (sun) plants grown in monocropping and intercropping systems (1ses:1sun; 1ses:2sun, and 2ses:1sun, row ratio) was conducted to evaluate growth and N2-fixation using 13C and 15N natural abundance techniques. The results showed that 1ses:1sun surpassed the other treatments in terms of nitrogen (N) and dry matter yields (DM). However, 1ses:2sun gave the highest seed and oil production and showed the greatest N2-fixation. Sesbania plants in the 1ses:2sun fixed almost identical amounts of N2 in mono and intercropping systems. Moreover, soil N-uptake was the lowest among other treatments. These results give an advantage to the 1ses:2sun treatment over other treatments in terms of soil N consumption and N2 fixation to meet sesbania's N requirements. Nevertheless, 2ses:1sun seemed to be an inappropriate treatment. On the other hand, it could be suggested from ‰D13C data that plants in the intercropping systems appeared not to be subjected to any abiotic stress during the growing period.
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Peroxidase activity and isoforms in the leaves of apple tree varieties differing in scab resistance
Статья научная
27 species and varieties were tested for resistance to leaf scab. Changes in the activity of peroxidase enzyme and the set of enzyme isoforms in leaves of apple tree differing in resistance to this pathogen.
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Статья научная
Background: Bellamya bengalensis is an important bioresource of the freshwater ecosystem of India. This edible mollusc is filter feeder, indigenous diet of human, poultry and fishery. Natural habitat of this freshwater gastropod mollusc bears the risk of contamination by agricultural pesticide fenvalerate, a synthetic type II pyrethroid. Hemocytes are the immuno effector cells of molluscs which are affected by environmental toxins or pathogenic microorganisms. Hemocytes perform various types of immunological functions such as phagocytosis, cytotoxic response etc. Results: Experimental exposure of fenvalerate resulted in impairment of phagocytic efficacy and alteration in the generation of phenoloxidase in B. bengalensis. Conclusion: The alteration of phagocytic response and generation of phenoloxidase of hemocytes, exposed to experimental concentrations of fenvalerate under static laboratory condition have been determined to establish as biomarker of aquatic toxicity in toxin contaminated natural habitat.
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