Salt Toxicity Research Articles

Physiological responses to salt stress of salt-adapted and directly salt (NaCl and NaCl+Na2SO4 mixture)-stressed cyanobacterium Anabaena fertilissima.

Soil salinity in nature is generally mixed type; however, most of the studies on salt toxicity are performed with NaCl and little is known about sulfur type of salinity (Na2SO4). Present study discerns the physiologic mechanisms responsible for salt tolerance in salt-adapted Anabaena fertilissima, and responses of directly stressed parent cells to NaCl and NaCl+Na2SO4 mixture. NaCl at 500mM was lethal to the cyanobacterium, whereas salt-adapted cells grew luxuriantly. Salinity impaired gross photosynthesis, electron transport activities, and respiration in parent cells, but not in the salt-adapted cells, except a marginal increase in PSI activity. Despite higher Na+ concentration in the salt mixture, equimolar NaCl appeared more inhibitive to growth. Sucrose and trehalose content and antioxidant activities were maximal in 250mM NaCl-treated cells, followed by salt mixture and was almost identical in salt-adapted (exposed to 500mm NaCl) and control cells, except a marginal increase in ascorbate peroxidase activity and an additional fourth superoxide dismutase isoform. Catalase isoform of 63kDa was induced only in salt-stressed cells. Salinity increased the uptake of intracellular Na+ and Ca2+ and leakage of K+ in parent cells, while cation level in salt-adapted cells was comparable to control. Though there was differential increase in intracellular Ca2+ under different salt treatments, ratio of Ca2+/Na+ remained the same. It is inferred that stepwise increment in the salt concentration enabled the cyanobacterium to undergo priming effect and acquire robust and efficient defense system involving the least energy.

Nano-silicon alters antioxidant activities of soybean seedlings under salt toxicity.

Materials with a particle size less than 100nm are classified as nano-materials. The physical and chemical properties of nano-materials can vary considerably from those of bulk materials of the same composition. Silicon (Si) still fails to get recognized as an essential nutrient for plant growth and development, however the beneficial effects in terms of growth, biotic and abiotic stress resistance have been indicated in a variety of plant species for their growth. The aim of this study was to investigate the effects of different nano-silicon rates on the growth and antioxidant activities of soybean (Glycine max L. cv. M7) under salt stress. The results showed that salinity decreased shoot and root dry weight, potassium (K+) concentration in the root and leaf; however, increased sodium (Na+) concentration, catalase, peroxidase, ascorbate peroxidase and superoxide dismutase activities, phenolic components, ascorbic acid and α-tocopherol contents, lipid peroxidation, hydrogen peroxide, and oxygen radical's concentration. Between the treatments, 0.5 and 1mM of nanosilicon oxide (nano-SiO2) improved shoot and root growth of seedlings. In contrast, a foliar application of SiO2 at 2mM reduced the soybean growth. Overall, exogenous nano-silicon alleviated the salt stress by increase in K+ concentration, antioxidant activities, non-enzymatic compounds and decreasing of Na+ concentration, lipid peroxidation, and reactive oxygen species production.

Мелиорация включенных в севооборот солонцовых почв Прикаспийской низменности сернокислотными отходами

The paper concerns the problems of making healthy salinized soils of pre-Caspian lowland in Azerbaijan Republic by chemical melioration. As a result of carried out experiments it has been determined that washing soils by water results in gyps leaching in the soils and formation alkaline salts. It leads to soda formation, salinization of soils and alkalıne formation. Though washing by drywall does not result in new formation of precipitated gyps, its application as meliorant presents formation of alkaline salts and salinization of solis. Gypsing of soils significantly optimizes leaching of salts, especially release of chlorine and sulphatization. However desalinization of soils till the toxicity border is achieved neither in the layer 0...50 cm, nor 0...100 cm. It has been determined that use of weak solution of sulphuric acid brought to desalination of upper 0...50 cm layer till the limit of salt toxicity deep desalinization of soils (to 150 cm) and high content of residue of non toxic salts lowering harmful influence of excludes possibility of restoration of soil salinization after washing. High content of non-toxic salts in residue after washing salinization with the reduce of toxic salts to 22...36 % allows to increase limit of salts toxicity after washing till 0.8...1.0 % on density residue.

Photosynthetic Responses of a Wheat Mutant (Rht-B1c) with Altered DELLA Proteins to Salt Stress

Salinity increases in the world’s land area and significantly affects the rate of photosynthesis and corresponding plant growth. In this study, the impact of salt stress (200 mM NaCl equivalent to an electrical conductivity of 18.6 mS cm−1) on the photosynthetic apparatus and some growth parameters were investigated in wheat DELLA mutant (Rht-B1c) and wild-type (Rht-B1a) seedlings grown on a half-strength Hoagland solution. Results revealed that salt toxicity was alleviated in the Rht-B1c mutant compared to the Rht-B1a wild type, as manifested by less-reduced leaf pigment content, relative water content, and photochemical activity of photosystem II (PSII) and photosystem I (PSI) after a 9-day salt exposure of plants. Compared to the wild-type wheat, a higher capacity for PSI-dependent cyclic electron flow, preventing the photosynthetic apparatus from oxidative damage, was observed in the mutant plants before and after salt treatment. In addition, an increase of PsaB proteins was detected in the mutant plants after long-term salt stress unlike the wild type. The observed higher oxidation level of P700 (P700+) in the mutant was consistent with higher abundance of PSI-related protein complexes. The data demonstrated that alterations in thylakoid membrane proteins and/or their structural reorganization in wheat DELLA mutant (Rht-B1c) significantly contribute to the alleviation of salt-induced damage of the photosynthetic apparatus. Molecular mechanisms involved in the photosynthetic responses of wheat DELLA mutants to salt stress are discussed.

Predation cues influence metabolic rate and sensitivity to other chemical stressors in fathead minnows (Pimephales promelas) and Daphnia pulex.

The response of aquatic species to contaminants is often context dependent as illustrated by the influence that predation cues can have on the toxicity of some chemicals. We sought to gain additional insight into this interaction by examining how predation cues (alarm cue and fish kairomone) influence metabolic rate and the acute toxicity of sodium chloride and cadmium to fathead minnow larvae (Pimephales promelas) and sodium chloride to Daphnia pulex neonates. Consistent with a "flight or fight" response, the metabolic rate of fish larvae was elevated in the presence of alarm cue and growth of the minnows was also significantly reduced when exposed to alarm cue. The average 48-h LC50 for fathead minnows exposed to sodium chloride was significantly lower in the presence of alarm cue and kairomone combined as compared to tests with the salt alone. Analysis of the dose and survival response indicated alarm cue increased sensitivity of the fish to mid-range salt concentrations in particular. These results suggest an energetic cost of exposure to predation cues that resulted in enhanced toxicity of NaCl. Exposure to kairomone alone had no significant effect on salt toxicity to the minnows, which could be related to a lack of previous exposure to that cue. The acute toxicity of cadmium to the fish larvae was also not affected by the presence of predation cues which could be due to a metal-induced sensory system dysfunction or reduced bioavailability of the metal due to organic exudates from the predation cues. In contrast to the fathead minnow results, the metabolic rate of D. pulex and toxicity of NaCl to the daphnids were reduced in the presence of certain predator kairomones. This suggests an anti-predator response that enhanced tolerance to the salt. This study illustrates that the effect of predation cues on toxicity of aquatic contaminants can vary significantly based on the prey species, type of cue, and chemical stressor.

Effect of lignite on alleviation of salt toxicity in soybean (Glycine max L.) plants

Salt toxicity of agricultural land is a natural phenomenon which is due to agricultural irrigation. This toxicity is harmful to crop productivity via increasing oxidative stress products. In a factorial controlled trial, four levels of lignite-enriched soil (soil lignite content: none, 50, 75 and 100 g kg−1) were exposed to three levels of soil salinity (0, 5 and 10 dS m−1 NaCl). Then reactive oxygen species (ROS) generation (hydrogen peroxide and superoxide radical), lipid peroxidation, antioxidant enzymes activities (peroxidase, catalase and super oxide dismutase), proline, glycine betaine, soluble sugars and soluble protein contents of soybean plants were compared across different lignite concentration and saline toxicity. Under the 5 and 10 dS m−1 NaCl, sodium entry to the leaf and root cells, hydrogen peroxide concentration, superoxide radical generation, lipid peroxidation and osmoprotectants creation increased and consequently plant growth reduced (12–49%). Lignite applications by improving the cation exchange capacity of soil (8–16%), enriched the leaf and root cells with potassium (5–26%), calcium (40–56%), magnesium (30–42%) and inhibited the sodium entry to the cells, and consequently increased potassium/sodium ratio and reduced oxidative stress, antioxidant activities and synthesis of osmoprotectants in soybean leading to increased plant biomass (18–37%). Lignite usage in 75 and 100 g kg−1 soil showed a better effect than 50 g kg−1 soil on reducing harmful effects of salt toxicity. Soil enrichment with lignite improves plant tolerance to salt toxicity via decreased oxidative stress.

How can salicylic acid and jasmonic acid mitigate salt toxicity in soybean plants?

This research was undertaken to assess the impact of 1mM salicylic acid (SA) and 0.5mM jasmonic acid (JA) on alleviation of oxidative, ionic and osmotic stresses of different levels of salinity (0, 4, 7, 10 dS m−1 NaCl, respectively). Salinity increased the contents of glycine betaine, proline, soluble sugars, proteins and the activities of peroxidase, catalase, superoxide dismutase, ascorbate peroxidase, and the amount of malondialdehyde and sodium ion of soybean leaves, but decreased the leaf water content, membrane stability index, potassium and calcium ions, chlorophylls content, chlorophyll stability index, plant biomass and seed yield. Foliar spray of JA reduced Na+ entry to the cells, while enhancing the glycine betaine and soluble proteins content, antioxidant enzymes activity, membrane stability index and leaf water content. This treatment had no effect on potassium and the calcium ions content, chlorophyll contents, chlorophyll stability index, soluble sugars, plant biomass and seed yield. In contrast, SA enriched the leaf cells with potassium and calcium ions under different levels of salt stress and increased glycine betaine, soluble sugars, proteins, antioxidant enzymes, leaf water content, membrane stability index, chlorophyll content and chlorophyll stability index, but reduced proline content. These superiorities of SA treatment led to considerable improvement in plant biomass (10%) and seed yield (17%) of soybean.

Physiological processes associated with salinity tolerance in an alfalfa half‐sib family

AbstractWe previously reported an alfalfa half‐sib family, HS‐B, with improved salt tolerance, compared to parental plants, P‐B. In this study, we conducted additional experiments to address potential physiological mechanisms that may contribute to salt tolerance in HS‐B. Vegetatively propagated HS‐B and P‐B plants were treated with a nutrient solution (control) or a nutrient solution containing NaCl (EC = 12 dS/m). Shoots and roots were harvested at various time points after treatment for quantification of proline, soluble sugar, and H2O2 using spectrophotometers. Subcellular localization and quantification of Na in roots were conducted using a Na+‐specific dye under a confocal microscope. HS‐B produced 86 and 89% greater shoot and root dry biomass, respectively, compared to parental plants, P‐B, under salinity in the greenhouse. Under saline conditions the HS‐B shoots accumulated 115% and roots 55% more soluble sugars than P‐B counterparts. The non‐saline HS‐B shoots, however, showed 72% less soluble sugars than the non‐saline P‐B plants. Under saline conditions HS‐B accumulated 39% less proline in shoots, while roots accumulated 56% more proline, compared to their P‐B parents. HS‐B plants also showed a greater reduction of stomatal conductance under mild saline stress. HS‐B shoots and roots contained 3–4 times less reactive oxygen species (H2O2) after salt treatment compared to P‐B plants. Sodium localization and distribution analysis using Na+‐specific dye revealed HS‐B plants accumulated 88% and 48% less Na+ in stele and xylem vessels compared to P‐B. The study provides insights into the potential mechanisms that may contribute to salt tolerance in HS‐B: maintaining RWC by accumulating soluble sugars while reducing transpiration, maintaining healthy status by reducing oxidative stresses, and preventing salt toxicity by reducing accumulation of Na+ inside root cells and xylem.

Knockout of the primary sclerosing cholangitis-risk gene Fut2 causes liver disease in mice.

Liver pathology in Fut2-/- mice is dominated by consequences of portosystemic shunting resulting in microcirculatory disturbances, mild (secondary) periductal fibrosis, and sensitivity toward human bile salt toxicity. (Hepatology 2017;66:542-554).

Exogenous Glutathione Modulates Salinity Tolerance of Soybean [Glycine max (L.) Merrill] at Reproductive Stage

In this study, we evaluated salt stress responses of 11 soybean genotypes and explored the protective roles of exogenous glutathione (GSH) against salt toxicity by assessing various biochemical and yield-attributing parameters. Exposure of the soybean genotypes to salt stress at the reproductive (R1) stage significantly decreased their yields by down-regulating the yield-contributing parameters as compared with unstressed controls. The highest decrease was found in number of seeds plant−1, yield plant−1, and number of pods plant−1, whereas the lowest decrease was recorded in number of seeds pod−1. Exogenous GSH was found to be effective in improving salinity tolerance, and the highest positive effects of GSH were recorded in terms of yield plant−1, number of seeds plant−1 and number of pods plant−1, whereas its lowest effect was observed with respect to the 100-seed weight. Cluster analysis of the genotypes based on yield-contributing and yield data revealed different levels of salt tolerance. Notably, BINA-01 and -02, and BINA-04 were recognized as the highest and lowest salt-tolerant genotypes, respectively. Furthermore, exogenous GSH alleviated oxidative stress in the representative contrasting genotypes at the vegetative (V3) stage by decreasing salt-induced accumulation of malondialdehyde and hydrogen peroxide. Taken together, our findings revealed that exogenous GSH application can minimize oxidative stress and contribute to the improvement of yield-contributing parameters, leading to improved yield in soybean genotypes under salt stress. Further investigations on molecular aspects will enable us to gain an in-depth understanding of how exogenous GSH can improve salinity tolerance in soybean, particularly at reproductive stage, to discover relevant pathways for biotechnological manipulation.

Regulation of plants metabolism in response to salt stress: an omics approach

In recent era, some man-made and natural activities are responsible for causing salt stress that affects each component of environment. Among several components, plant is one of the essential components, and with the consequence of excess salts accumulation in the environment their metabolic activities may get affected. Plants exhibit hyper-osmotic stress and ion disturbance in the presence of excess salt accumulation. To combat this stress situation, some metabolites/or stress-responsive gene(s) and proteins are synthesized by the plants to mitigate the salt toxicity. Therefore, to reduce the impact of salt stress on yield and other physiological activities of plants it is essential to know the whole pathway through which plant’s metabolism get affected in the presence of salt. The present review is also dealing with the same objective and special focus is given to the omics tools, such as genomics, proteomics and metabolomics to discuss the different ways of tolerance mechanism in the plant system against salt toxicity.

Salt tolerance evaluation of nine indigenous Greek olive cultivars

ABSTRACTThe present work was aimed to evaluate nine Greek olive (Olea europaea L.) cultivars for tolerance to sodium chloride (NaCl) salinity, most of which have never been evaluated or considered to be extinct, in order to be used in the future as olive rootstocks in areas with salt toxicity problems.One-year old, self-rooted trees of the cultivars ‘Aetonicholia Kynourias,’ ‘Arvanitolia Serron,’ ‘Ntopia Atsicholou,’ ‘Koroneiki,’ ‘Lefkolia Serron,’ ‘Ntopia Pierias,’ ‘Petrolia Serron,’ ‘Smertolia,’ and ‘Chrysophylli’ were subjected to 0, 50, 100, and 200 mM NaCl, for six months, in nutrient solution pot experiment. The experiment was conducted as a completely randomized factorial design with four replications (of one tree), with the factors being the cultivar (nine levels) and the salt concentration (four levels). According to plant growth parameter results, ‘Arvanitolia Serron’ followed by ‘Lefkolia Serron’ were found to be the most salt tolerant cultivars to growth reduction. The same cultivars accumulated less sodium (Na) and chlorine (Cl) in the leaves by retaining more ions in the roots. Moreover, ‘Arvanitolia Serron’ was able to maintain high potassium (K) levels and K/Na ratio in younger leaves under salinity.

The effect of silver nanoparticle on Fenugreek seed germination under salinity levels

A study was conducted to evaluate the effect s of silver nanoparticles for ameliorating negative effects of salinity on germination and growth of Fenugreek seeds. In order to investigate salinity stress on Fenugreek germination indices, an experiment was carried out in Iran from October 2014 to November 2014 at Ferdowsi University of Mashhad, in the biotechnology Laboratory, to create salinity stress, sodium chloride (NaCl) at the levels of 0 (as control), 5, 10, 15 and 20 dS/m and Five levels of silver nanoparticles (0, 10, 20, 30 and 40 μg mL–1) on Fenugreek seed (Trigonella foenum-graecum); were tested Germination characteristics such as total germination (GT), Germination Speed Index (GSI), Shoot and Root of seedling long, Fresh Mass and Dry Mass were measured. Results showed the great effects of silver nanoparticles to improve salinity stress on Fenugreek seed germination. Results showed a significant reduction in germination percent and seedling growth due to the salinity stress while significantly increased with silicon nano-particles application. In without silver nanoparticle low level of salinity (0 dS/m) increased seed germination percentage, while the high levels (5, 10, 15 and 20 dS/m) inhibited the seed germination significantly. The results showed that the effect of AgNPs was significant on germination percentage in P ≤ 0.05. Overall, application of AgNPs was beneficial in improving salinity tolerance in the Fenugreek seedling and its application may stimulate the differences defense mechanisms of plants against salt toxicity.

The acute toxicity of major ion salts to Ceriodaphnia dubia. II. Empirical relationships in binary salt mixtures.

Many human activities increase concentrations of major geochemical ions (Na+1 , K+1 , Ca+2 , Mg+2 , Cl-1 , SO4-2 , and HCO3-1 /CO3-2 ) in freshwater systems, and can thereby adversely affect aquatic life. Such effects involve several toxicants, multiple toxicity mechanisms, various ion interactions, and widely varying ion compositions across different water bodies. Previous studies of individual salt toxicities have defined some useful relationships; however, adding single salts to waters results in atypical compositions and does not fully address mixture toxicity. To better understand mechanisms and interactions for major ion toxicity, 29 binary mixture experiments, each consisting of 7 to 8 toxicity tests, were conducted on the acute toxicity of major ion salts and mannitol to Ceriodaphnia dubia. These tests showed multiple mechanisms of toxicity, including: 1) nonspecific ion toxicity, correlated with osmolarity and to which all ions contribute; and 2) cation-dependent toxicities for potassium (K), magnesium (Mg), and calcium (Ca) best related to their chemical activities. These mechanisms primarily operate independently, except for additive toxicity of Mg-dependent and Ca-dependent toxicities. These mixture studies confirmed ameliorative effects of Ca on sodium (Na) and Mg salt toxicities and of Na on K salt toxicity, and further indicated lesser ameliorative effects of Ca on K salt toxicity and Mg on Na salt toxicity. These results provide a stronger basis for assessing risks from the complex mixtures of ions found in surface waters. Environ Toxicol Chem 2017;36:1525-1537. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Synthetic Cathione and Cannabinoid Toxicity and Treatment

Submit Manuscript | http://medcraveonline.com [4] and 4-methylcathinone (mephedrone). MDPV is a dopamine and norepinephrine reuptake inhibitor that acts as a stimulant. Mephedrone is thought to be a monoamine reuptake inhibitor. The mechanism of action includes an increase in serotonin, norepinephrine, and dopamine levels. Mephedrone [5] is a derivative of phenethylamine, which is the active ingredient in the African plant khat. Khat is similar to amphetamine and is associated with a history of abuse. Federal legislation was passed in September of 2011 to restrict the possession or distribution of any substance containing MDPV, methadone, or methylone. However, synthetic stimulants are difficult to regulate. These substances are easily manipulated into other compounds as soon as legislation banning a specific compound is passed. The drug class of phenethylamines, which these compounds belong to, is unable to be banned outright because this class also contains FDA-approved medications, such as bupropion, dopamine, and epinephrine. The Federal Analog Act (21 USC 813) was passed in an effort to avoid the need for legislation to be passed on each individual analog. However, the Analog Act only applies to products meant for human consumption. Bath salts are labeled “not for human consumption” as a way around this law. The American Association of Poison Control Centers [6] report the number of calls related to bath salts increasing from 304 in 2010 to 2,655 in 2012. The patients’ ages ranged from 1 day to 61 years, with a median age of 29.2 years. The clinical effects were primarily neurological or cardiovascular. In a recent retrospective review of hospital visits reported to poison control centers, 1,633 patients with reported bath salt toxicity were examined. Death resulted in 0.6% of patients. The reported reasons for death include suicide, serotonin syndrome, fever, and seizures. Major outcomes, defined as life threatening or resulting in significant disability or disfigurement, occurred in 15.5% of patients. The route of administration and age of the patient have been shown as factors influencing the occurrence of major outcomes or death. The injection of bath salts was predicted to have more serious effects than snorting bath salts. There was no difference in major outcomes or death between oral ingestion and injection. Patients aged 47 years or greater also had a higher risk of major outcomes than the younger populations. This older population also was shown to have higher rates of injection and co-ingestions, as well. Co-ingestions of other substances presenting with bath salt toxicities have a relatively low occurrence as compared to other substances of abuse, around 26%. The most common co-ingestion was with opioids in 6.2% of the reported cases from November 2011 to November 2012, followed by marijuana in 5.4% of reported case. This data suggests that the majority of bath salt abusers are seeking “legal highs” [7]. The treatment of the sympathomimetic toxidrome associated with bath salts should start with the administration of benzodiazepines. It is reported that benzodiazepines are used in about 60% of patients. Amphetamine-induced seizures typically result from an imbalance of excitatory and inhibitory neurotransmitters that do not originate in a specific location of the brain. Amphetamine-induced seizures respond to benzodiazepines, which also act to sedate the patient for the safety of the healthcare team. Phenytoin and Fosphenytoin should not be used as they work by isolating the focal point of a seizure and can induce arrhythmias. Lorazepam and Diazepam are the preferred agents via the intravenous route. Sedation is also a common treatment strategy used in this patient population. Sedative agents commonly used include propofol, barbiturates, and antipsychotics. Almost 10% of patients presenting with bath salt intoxication require ventilation. Psychotic symptoms typically resolve within 12 hours to 3 days of admission, although one patient remained symptomatic for 11 days. Caution must be used when administering anti-psychotic medications for drug-induced psychoses, as they may lower the seizure threshold.

Effects of iodized salt on the histopathology of the gills and liver in Rhamdia quelen and Metynnis maculatus

Table salt has been used as a reference substance in toxicological studies on fish and as an antiparasitic agent in aquaculture. The objectives of this work were to evaluate the sensitivity of Rhamdia quelen and Metynnis maculatus to iodized salt and to assess the possible changes in the gills and liver resulting from subchronic exposure of fish to this compound. The iodized salt toxicity levels after 96 h of exposure were 11.4 and 10.8 g L−1 for R. quelen and M. maculatus. None of the observed changes in the livers of the studied fish could be unequivocally correlated with salt exposure. In turn, it could not be entirely ruled out that the changes found in the gills, including epithelial lifting, oedema formation and vascular congestion, were caused by exposure of fish to salt.

A multidrug cocktail approach attenuates ischemic-type biliary lesions in liver transplantation from non-heart-beating donors

Ischemic-type biliary lesions (ITBL) are the most troublesome biliary complication after liver transplantation (LT) from non-heart-beating donors (NHBD) and frequently result in death or re-transplantation. In transplantation process, warm ischemia (WI) in the donor, cold ischemia and reperfusion injury in the recipient altogether inducing ischemia–reperfusion injury (IRI) is strongly associated with ITBL. This is a cascading injury process, involving in a complex series of inter-connecting events causing variety of cells activation and damage associated with the massive release of inflammatory cytokines and generation of reactive oxygen species (ROS). These damaged cells such as sinusoidal endothelial cells (SECs), Kupffer cells (KCs), hepatocytes and biliary epithelial cells (BECs), coupled with immunological injury and bile salt toxicity altogether contribute to ITBL in NHBD LT. Developed therapeutic strategies to attenuate IRI are essential to improve outcome after LT. Among them, single pharmaceutical interventions blocking a specific pathway of IRI in rodent models play an absolutely dominant role, and show a beneficial effect in some given controlled experiments. But this will likely prove ineffective in complex clinical setting in which more risk parameters are involved. Therefore, we intend to design a multidrug cocktail approach to block different pathways on more than one stage (WI, cold ischemia and reperfusion) of the process of IRI-induced ITBL simultaneously. This multidrug cocktail will include six drugs containing streptokinase, epoprostenol, thiazolidinediones (TZDs), N-Acetylcysteine (NAC), hemin and tauroursodeoxycholic acid (TUDC). These drugs show protective effects by targeting the different key events of IRI, such as anti-inflammatory, anti-fibrosis, anti-oxidation, anti-apoptosis and reduced bile salt toxicity. Ideally, the compounds, dosage, and method of application of drugs included in cocktail should not be definitive. We can consider removing or adding some drugs to the proposed cocktail based on further research. But given the multitude of different combinations, it is extremely difficult to determent which combination is the optimization design. Nevertheless, regardless of the difficulty, our multidrug cocktail approach designed to block different mechanisms on more than one stage of IRI simultaneously may represent a future preventive and therapeutic avenue for ITBL.

Ectopic expression of a cytochrome P450 monooxygenase gene PtCYP714A3 from Populus trichocarpa reduces shoot growth and improves tolerance to salt stress in transgenic rice.

SummaryIn Arabidopsis thaliana and Oryza sativa, the cytochrome P450 (CYP) 714 protein family represents a unique group of CYP monooxygenase, which functions as a shoot‐specific regulator in plant development through gibberellin deactivation. Here, we report the functional characterizations of PtCYP714A3, an OsCYP714D1/Eui homologue from Populus trichocarpa. PtCYP714A3 was ubiquitously expressed with the highest transcript level in cambium–phloem tissues, and was greatly induced by salt and osmotic stress in poplar. Subcellular localization analyses indicated that PtCYP714A3‐YFP fusion protein was targeted to endoplasmic reticulum (ER). Expression of PtCYP714A3 in the rice eui mutant could rescue its excessive‐shoot‐growth phenotype. Ectopic expression of PtCYP714A3 in rice led to semi‐dwarfed phenotype with promoted tillering and reduced seed size. Transgenic lines which showed significant expression of PtCYP714A3 also accumulated lower GA level than did the wild‐type (WT) plants. The expression of some GA biosynthesis genes was significantly suppressed in these transgenic plants. Furthermore, transgenic rice plants exhibited enhanced tolerance to salt and maintained more Na+ in both shoot and root tissues under salinity stress. All these results not only suggest a crucial role of PtCYP714A3 in shoot responses to salt toxicity in rice, but also provide a molecular basis for genetic engineering of salt‐tolerant crops.

Reuse of microalgae grown in full-scale wastewater treatment ponds: Thermochemical pretreatment and biogas production

This study assessed thermochemical pretreatment of microalgae harvested from a full-scale wastewater treatment pond prior to its anaerobic digestion using acid and alkaline chemical doses combined with thermal pretreatment at 80°C. Results indicated that alkaline and thermal pretreatment contributed mostly to glycoprotein and pectin solubilisation; whilst acid pretreatment solubilised mostly hemicellulose, with lower effectiveness for proteins. Regarding the anaerobic biodegradability, biochemical methane potential (BMP) tests showed that final methane yield was enhanced after almost all pretreatment conditions when compared to non-pretreated microalgae, with the highest increase for thermochemical pretreatment at the lowest dose (0.5%), i.e. 82% and 86% increase for alkaline and acid, respectively. At higher doses, salt toxicity was revealed by K+ concentrations over 5000mg/L. All BMP data from pretreated biomass was successfully described by the modified Gompertz model and optimal condition (thermochemical 0.5% HCl) showed an increase in final methane yield and the process kinetics.

Response of Rice under Salinity Stress: A Review Update

Salinity has been a key abiotic constraint devastating crop production worldwide. Attempts in understanding salt tolerance mechanisms has revealed several key enzymes and altered biochemical pathways inferring resistance to crop plants against salt stress. The past decades have witnessed extensive research in development of salt tolerant cultivars via conventional means, improvised by modern era molecular tools and techniques. Rice (Oryza sativa L) is the staple food crop across several countries worldwide. Being a glycophyte by nature, its growth is severely imparted in presence of excess salt. Rice is susceptible to salinity specifically at the early vegetative and later reproductive stages and the response of the crop to excessive salt toxicity at biochemical and molecular level as well as physiological level is well studied and documented. An understanding of the specific response of rice to ion accumulation at the toxic level can aid in identifying the key factors responsible for retarded growth and limited production of rice with the future scope of mitigating the same. The present review summarizes the differential responses of rice, in particular, to salt toxicity enumerating the detailed morphological, physiological, biochemical and molecular changes occurring in the plant. An attempt to explain salinity tolerance and its future scope and implications in screening for salt tolerance has also been elucidated in the present study.