Addition Of Salicylic Acid Research Articles

Enhancement of Plumbagin Production through Elicitation in In Vitro-Regenerated Shoots of Plumbago indica L.

Plumbago indica L. contains a valuable bioactive compound called plumbagin. Elicited regenerated shoots grown in vitro could be another source of high-yielding plumbagin. The purpose of this investigation was to examine the effects of elicitor type and concentration, as well as elicitation period, on plumbagin content in in vitro-regenerated shoots of P. indica. Nodal explants were cultured on Murashige and Skoog (MS) medium containing 1 mg/L benzyladenine (BA) in combination with 0-150 mg/L yeast extract or 50-150 µM salicylic acid for four weeks. Plumbagin levels of 3.88 ± 0.38% and 3.81 ± 0.37% w/w g dry extract were achieved from the 50 and 100 mg/L yeast extract-elicited shoots, which were higher than the value obtained for the control. However, the addition of salicylic acid did not increase the plumbagin content. In the elicitation period experiment, nodal explants were cultured on MS medium supplemented with 1 mg/L BA and 50 mg/L yeast extract for durations of three, four and five weeks. The 4-week yeast extract-elicited shoot had a maximum plumbagin content of 3.22 ± 0.12% w/w g dry extract, greater than that of the control. In summary, the plumbagin content of the in vitro P. indica shoots was enhanced by 4-week elicitation using 50 mg/L yeast extract.

Efficacy and phytotoxicity of various thiabendazole and tebuconazole ratios in a fungicidal mordant

When developing combined preparations, a possible phytotoxic effect should be considered, depending on the dose of the mordant. Fusarium oxysporum and Pyrenophora graminea strains were cultured in a liquid enrichment culture with the addition of fungicides at a concentration of 1.5; 2.5; 3.3 ppm. Wheat grains of the Avesta variety were treated with thiabendazole and tebuconazole in the following doses: 20 g a.d./ t, 30 g a.d./t, 60 g a.d./t, 80 g a.d./t, 100 g a.d./t of grain. The effectiveness of tebuconazole and thiabendazole on mycelium growth slightly depended on their concentration. A.d. mutually reinforced each other. The synergism of the action of two a.d. is revealed. The analysis of variance showed that the effect of tebuconazole was greater than the thiabendazole effect. For both strains, the optimal ratios of tebuconazole and thiabendazole are 1.5:2.5 ppm. The addition of salicylic acid is effective at ratios of 2.5:0 and 2.5:3.3. The mixture of thiabendazole and tebuconazole reduced the germination energy of the grains mainly due to the appearance of abnormal seedlings. A composition of active substances for seed etching is proposed, including the following ratios of components, pts. wt.: tebuconazole 20-100, thiabendazole 20-150.

Assessment of the enhancement potential of salicylic acid on physicochemical, mechanical, barrier, and biodegradability features of potato starch films

Filmogenic suspensions based on starch (S) and salicylic acid/starch (SA-S) were prepared and used to produce casted films (TPS and SA-TPS). An extensive characterization was conducted on both suspensions and casted films to assess their properties. Results evidenced that after storage for 120 days at 4 °C and 25 °C, the mold and yeast counts were significantly lower in the SA-S than in the S suspensions. Moreover, SA-S had a much lower initial viscosity than S. In reference to the films produced, salicylic acid caused a significant increase in film crystallinity, as well as a 2.3-fold increase in stress at break and a 3.8-fold increase in Young's modulus over the control films. Additionally, compared to TPS, the SA-TPS films exhibited a 46% decrease in water vapor permeability. All films showed a high biodegradation extent (≥85%) upon 75 days of home composting. These findings suggest that the salicylic acid addition at low concentrations (2 mM) can be a cost-effective approach for the development of highly stable starch filmogenic suspensions and also biobased films with distinguishing properties.

Response of Phenolic Compounds in Lippia graveolens Kunth Irrigated with Aquaculture Wastewater and Steiner Solution

Lippia graveolens is one of the most important aromatic species in Mexico due to antioxidant and antibiotic activities reported in its essential oil. The aim of this work was to assess the effect of irrigation with aquaculture wastewater and salicylic acid addition on the production of phenolic compounds in L. graveolens. L. graveolens plants (14) were irrigated with aquaculture wastewater and (14) using Steiner solution for 28 days; at the same time, salicylic acid was exogenously applied at 0.0 (control), 0.5 and 1.0 mM concentrations in both treatments at 5 and 19 experimental days. The total phenolic content was measured by Folin–Ciocalteu, the flavonoid content was determined by the aluminum chloride method, and the antioxidant capacity was measured by DPPH and FRAP assays. The results showed an increase in the total phenolic and flavonoid content in plants irrigated with aquaculture wastewater solution (17.25 ± 2.35 to 38.16 ± 4.47 mg eq GA·g⁻1 W). The antioxidant capacity was higher in plants irrigated with Steiner solution (98.52 mg eq T·g⁻1 W). In conclusion, L. graveolens irrigated with aquaculture wastewater leads to an increase in the total phenolic content and Steiner-solution antioxidant capacity in plants.

Effect of Salicylic Acid and Nano-Silicon of the Enzymatic Activity for Potato Shoots Grown Under Salt Stress in Vitro

The experiment was conducted in the tissue culture laboratory, Department of Horticulture and Landscaping, College of Agriculture, Al-Qasim Green University during the September 2021 to June 2022. The experiment was conducted according to a complete randomized design (CRD) with two factors and ten replicates. The first factor included sodium chloride in three concentrations (0, 50, 100) mmol.L-1, and the second factor included five concentrations of salicylic acid and nano-silicon (0, 1.5 mg.L-1 nano-silicon, 3.0 mg.L-1 nano-silicon and 14 mg.L-1 salicylic acid, 28 mg.L-1 salicylic acid). The results of the experiment showed the interaction between sodium chloride and addition of salicylic acid or nano silicon to the MS medium, and there was a significant effect of the enzymatic activity and proline. The interaction treatment ( 100 mmol.L-1 NaCl with salicylic acid14 mg.L-1) recorded the highest activity of Peroxidase (43.03), compared with the interaction treatment (0 mmol.L-1 NaCl with salicylic acid14 mg.L-1) which recorded the lowest activity of the Peroxidase enzyme reached (23.22). The interaction treatment ( 50 mmol.L-1 NaCl with salicylic acid at a 14 mg.L-1) recorded the highest activity of the enzyme (14.13).Compared with the interaction treatment (0 mmol.L-1 NaCl with 28 mg.L-1 salicylic acid), which recorded the lowest activity of the catalase enzyme (8.89). The interaction treatment (100 mmol.l-1 NaCl without adding nano-silicon or salicylic acid ) recorded the highest average of shoots content of proline (0.868). Compared with the interaction treatment (0 mmol.L-1 NaCl with 14 mg.L-1 salicylic acid), which recorded the lowest average in proline content (0.555).

Effect of Salicylic Acid and Nano Silicon on the Morphological Traits of Potato Shoot Grown in Vitro Under Salt Stress

The experiment was conducted in the tissue culture laboratory, Department of Horticulture and Landscaping, College of Agriculture, Al-Qasim Green University during the September 2021 to June 2022. The experiment was conducted according to a complete randomized design (CRD) with two factors and ten replicates. The first factor included sodium chloride in three concentrations (0, 50, 100) mmol.L-1, and the second factor included five concentrations of salicylic acid and nano-silicon (0, 1.5 mg.L-1 nano-silicon, 3.0 mg.L-1 nano-silicon and 14 mg.L-1 salicylic acid, 28 mg.L-1 salicylic acid). The results of the experiment showed the interaction between sodium chloride and addition of salicylic acid or nano silicon to the MS medium, and there was a significant effect on most of the studied indicators. The interaction treatment without adding sodium chloride with salicylic acid at a concentration 28 mg.L-1 gave the highest rate in the shoots length. While the interaction treatment without adding sodium chloride with salicylic acid at a concentration 14 mg. L-1 gave the highest average of dry weight percentage. Also, the treatment of addition sodium chloride 50 mmol.L-1 with salicylic acid at a concentration of 14 mg.L-1 gave the highest average in the number of shoots.

Response of Different Levels of Salicylic Acid on Growth Characteristics, Chlorophyll Content, Yield Attributes and Yield of Black Gram (Vigna mungo L.) under Rainfed Condition

To study the response of different levels of salicylic acid on growth characteristics, chlorophyll intensity, yields attributes and yield of black gram (Vigna mungo L.) under rainfed conditions. The field experiment was conducted at Department of Crop Physiology, Chandra Shekhar Azad University of Agriculture & Technology, Kanpur, Uttar Pradesh, India during kharif season in the year 2017-18. The experiment was laid out in Randomized Block Design (RBD) with 10 Treatments replicated thrice and assigned in 30 plots. The treatment comprised as T1: Control, T2: Foliar application of salicylic acid @ 50 ppm at 20 DAS, T3: Foliar application of salicylic acid @ 50 ppm at 40 DAS, T4: Foliar application of salicylic acid @ 50 ppm at 60 DAS, T5: Foliar application of salicylic acid @ 100 ppm at 20 DAS, T6: Foliar application of salicylic acid @ 100 ppm at 40 DAS, T7: Foliar application of salicylic acid @ 100 ppm at 60 DAS, T8: Foliar application of salicylic acid @ 150 ppm at 20 DAS, T9: Foliar application of salicylic acid @ 150 ppm at 40 DAS, T10: Foliar application of salicylic acid @ 150 ppm at 60 DAS. The results showed significant increments in Growth attributes, relative water content (%), chlorophyll intensity (SPAD meter value), yield and yield attributes viz., plant height (36.50 and 38.10 cm) at 70 DAS and maturity, number of leaves plant-1(8.66, 23.66 and 22.0) at 35, 70 DAS and maturity, number of branches plant-1 (3.9, 8.60 and 10.33) at 35, 70 DAS and maturity, dry weight of plant-1(2.76, 6.12 and 5.01 g) at 35, 70 DAS and maturity, dry weight of stem plant-1(2.76, 7.12 and 7.96 g) at 35, 70 DAS and maturity, total dry weight of plant (4.96, 13.24 and 21.97 g) at 35, 70 DAS and maturity, total leaf area plant-1 (211.33 and 384.87 cm-2) at pre and post flowering, Relative water content (51.50 and 43.43) at Pre and post flowering, Chlorophyll content (49.93 and 40.90) at pre and post flowering, Number of pods plant-1 (46.00) at maturity, Dry weight of pods plant-1 (8.99g) at maturity, seed yield plant-1 (6.66 g), 100-Seed weight (4.41 g), Harvesting index (30.30%), Grain Yield (10.35 q ha-1) with the foliar application of salicylic acid @ 150 ppm at 60 DAS while minimum in control. The addition of salicylic acid under rainfed conditions resulted in significant increments in growth parameters, chlorophyll intensity, yield and yield attributes of black gram in rainfed conditions. Thus, it may be concluded that the foliar application of salicylic acid @ 150 ppm was found to be optimum concentration in enhancing growth and yield of a black gram over rest of treatment under rainfed conditions.

IN VITRO PRODUCTION OF ACTIVE COMPOUNDS IN THE CALLUS OF THE CHIA PLANT (SALVIA HISPANICA)

The latest research aimed to study the effects of plant growth regulators on inducing callus from the chia plant (Salvia hispanica) and stimulating it to produce some medicinal compounds in vitro. The study transpired at the Plant Tissue Culture Laboratory, College of Agriculture, University of Anbar, Iraq. The use of Murashige and Skoog (MS) nutrient medium containing 2,4-D Auxin (dichlorophenoxyacetic acid) had concentrations of 1.0, 2.0, and 3.0 mg L-1 and cytokinin benzyl adenine (BA) with concentrations of 0.0, 0.5, and 1.0 mg L-1. The use of their interactions continued to induce a perpetuation of callus. In another experiment, the salicylic acid at concentrations of 0, 10, 20, and 30 mg L-1 stimulated the callus to produce medicinal compounds. The results showed that for induction of callus and its sustainability in the leaves of the chia plant, the best concentration revealed 2,4-D at a rate of 3 mg L-1, which achieved the highest fresh and dry weight and dry matter percentage with values of 0.5151 g, 0.0723 g, and 13.531%, respectively. The results also showed that the addition of salicylic acid at the concentration of 10 mg L-1 to the nutrient media stimulated the formation of the active compounds.

Effects of Salicylic Acid to Control Bacterial Leaf Blight Disease (Xanthomonas oryzae pv. oryzae) on Three Varieties of Rice

ABSTRACTBacterial leaf blight is a disease in rice plants caused by Xanthomonas oryzae pv. oryzae. The use of resistant varieties is an effective, economic and easy way to do it, but it is limited by time and place so that it needs to be induced by the addition of salicylic acid. Salicylic acid is one of the compounds that can activate enzymes that play a role in plant resistance to pathogen infection. The purpose of this study was to determine the effect of the addition of salicylic acid to rice varieties to induce its resistance to bacterial leaf blight. The research was arranged in a factorial completely randomized design (CRD) consisting of 2 factors. The first factor used was mekongga rice varieties (V1); Ciherang (V2); and IPB 3S (V3), while the second factor is the concentration of salicylic acid consisting of 0 mM (K0); 7.5 mM (K1); 10 mM (K2); and 12.5 mM (K3) with each treatment repeated 3 times, and in each study unit there were 5 plants. Results showed that the addition of salicylic acid and the use of three varieties of rice can suppress the severity of the disease HDB, its resistance status increases when compared to control and increases the content of the phenol. The best treatment of 10 mM salicylic acid concentrations with Mekongga varieties (K2V2) can suppress the severity of the HDB disease by 18.47% by showing a moderately susceptible endurance status as well as the content of the phenol increased.Keywords : Salicylic Acid, Varieties of Rice, Xanthomonas oryzae pv. oryzae

Mengembangkan skenario panen porang satu musim melalui manipulasi tanam lebih awal dan perlambatan waktu dorman fase generatif dengan pemberian asam salisilat organik alami di lahan kering Lombok Utara

The research on the scenario of one-season porang harvest through crop manipulation and delaying dormancy time aims to determine the effect of salicylic acid in breaking the dormancy of porang bulbil seeds during seeding and to determine the effect of slowing down the dormant period of the generative phase, so it is expected to be an alternative porang cultivation technology that is profitable for farmers The method used in this study used a completely randomized design experiment on breaking dormancy and a randomized block design in an experiment with slowing down the dormancy time of the generative phase with four salicylic acid concentrations (0%, 0.5%, 1%, and 2%) with eight replicates were planted under rainfed conditions. The results showed that the concentration of salicylic acid (C7H6O3) 2% was the best treatment in increasing tuber weight (52.25%) compared to the control. Application of Salicylic Acid (2%) was significantly able to increase the vegetative growth of porang plants, which was shown by increasing plant height by 50.38% and breaking seed dormancy 14 days faster than the control (without the addition of Salicylic Acid). Furthermore, the delay in dormancy time occurred 1 month later than the control so that it could prolong the vegetative phase. The concentration of 2% salicylic acid is the best treatment, which can be recommended in the development of one-season porang cultivation technology that can increase farmers' profits.

Polymerization of l-lactide with SnCl2: A Low Toxic and Eco-friendly Catalyst

Polymerizations of l-lactide catalyzed either by neat SnCl2 or by SnCl2 + difunctional cocatalysts were conducted in bulk at 180, 160 and 140 °C with variation of the Lac/Cat ratio and time. With neat SnCl2 poly(L-lactide) having weight average molecular weights (uncorrected Mw’s) up to 190 000 g mol−1 were obtained mainly consisting of linear chains. Addition of salicylic acid or 1,1-bisphenol yielded a higher fraction of cyclic polylactides but lower molecular weights. Furthermore, SnCl2 was compared with Bu2SnCl2 and various other metal chlorides and the best results were obtained with SnCl2. With ethyl L-lactate as initiator SnCl2-catalyzed ROPs were performed at 120 °C and the lac/initiator ratio was varied. All these experiments were conducted under conditions allowing for comparison with ROPs catalyzed with neat Sn(II)-2-ethyhexanoate. Such a comparison was also performed with ε-caprolactone as monomer.

Foliar Spraying of Silicon Associated with Salicylic Acid Increases Silicon Absorption and Peanut Growth

Silicon (Si) combined with foliar spraying of salicylic acid (SA) can affect the absorption of this beneficial element. A study with Si non-accumulators plants (soybean and bean) observed that SA foliar spraying improved leaf absorption. However, this effect is unknown in peanut (Arachis hypogaea), a Si non-accumulator species. The aim of the present study was to assess the effect of applying Si to the leaves or roots, associated with foliar applications of SA, on Si absorption and dry weight production of peanut plants. An experiment was conducted with IAC OL4 peanut cultivars in pots filled with 6 L of sand. A randomized block design was used, in a 3 × 3 factorial scheme, as follows: Si application via leaves and roots in the form of monosilicic acid and the control (no Si) and three foliar applications of salicylic acid (0; 0.05; 0.15 mM), with five repetitions. The Si was supplied via nutrient solution (root) and leaves throughout the experiment, with three spraying treatments: at the end of the vegetative stage, onset of flowering and at the start of pod formation. The SA foliar sprayings were performed together with Si. Foliar silicon application was superior to its root counterpart at all SA concentrations. The greatest Si accumulation for root application was observed at a concentration of 0.05 mM of SA. Shoot dry weight and root dry weight production increased with Si. SA application, at a concentration of 0.05 mM, especially when associated with foliar Si, favored Si absorption and dry weight production in peanut plants. Foliar spraying of Si with the addition of salicylic acid is a new strategy for silicon supplementation in Si non-accumulators.

Improvement of the nutraceutical quality and yield of tomato by application of salicylic acid

Tomato fruits are a unique functional food and a natural reservoir of nutrients, antioxidants, vitamins and bioactive compounds that improve nutrition and human health. As an important vegetable throughout the world, tomatoes have attracted the attention of researchers to carry out various strategies to improve the functionality of this food aimed at the prevention of diseases, health and global well-being. An agronomic strategy in this study was to evaluate the influence of the application of "salicylic acid (SA)" on the yield and nutraceutical quality of the tomato crop, produced under hydroponic conditions. A completely randomized experimental design with six repetitions was used. SA at five doses (0.025, 0.05, 0.075, 0.1 and 0.125 mM) and one control were applied every 15 days in the nutritive solution under a hydroponic system on tomato plants. The evaluated variables were yield (total fruit weight per plant), fruit parameters (weight, diameter, firmness, and total soluble solids), percentage of weight loss and nutraceutical quality of tomato. The results obtained indicate that the addition of salicylic acid in nutritive solution increased the yield and biosynthesis of phytochemical compounds in tomato fruits, in relation to the control without application. In conclusion, to obtain a higher nutraceutical quality without affecting the tomato fruit yield, it is recommended to use the average concentration (0.125 mM) of SA.

Preparation of dye sensitized solar cell (DSSC) using isolated anthocyanin fromfruit sat (melastomamalabathricum l) dicopimented with salicylic acid as dye

A study has been conducted on the use of anthocyanin extract from fruits (Melastomamalabthricum L), which was incubated by the addition of salicylic acid as photosensitizer in DSSC solar cells. The objective of this study was to determine the optimum condition of the extracts of copigmenation which resulted in the optimum efficiency of DSSC solar cells by increasing the absorption ability of anthocyanin pigment photons.The method used is the method of copigmentation. Copigmentation is an anthocyanin reaction with a copigment compound to form a more complex anthocyanin structure with a number of double bonds that can absorb more photons than the original anthocyanin.. The results of dye characterization using UV-Vis and FTIR indicate a wider absorption spectrum and a more complex structure in antigianated anthocyanins when compared without copigmentation. Based on the results of the characterization of the prepared TiO2 thin film, obtained crystal size of TiO2 used ranged from 27.377 to 64.738 nm with a width of200-950 nm photocathode spekrum absorption. Based on the results of the research, it is found that the antiganant extract can be increased by DSSC solar cell efficiency from 0.62% to 1.32% with 24 hours of copigmentation time and 1: 2 concentration of concentration.

Transcriptome Analysis of Salicylic Acid Treatment in Rehmannia glutinosa Hairy Roots Using RNA-seq Technique for Identification of Genes Involved in Acteoside Biosynthesis.

Rehmannia glutinosa is a common bulk medicinal material that has been widely used in China due to its active ingredients. Acteoside, one of the ingredients, has antioxidant, antinephritic, anti-inflammatory, hepatoprotective, immunomodulatory, and neuroprotective effects, is usually selected as a quality-control component for R. glutinosa herb in the Chinese Pharmacopeia. The acteoside biosynthesis pathway in R. glutinosa has not yet been clearly established. Herein, we describe the establishment of a genetic transformation system for R. glutinosa mediated by Agrobacterium rhizogenes. We screened the optimal elicitors that markedly increased acteoside accumulation in R. glutinosa hairy roots. We found that acteoside accumulation dramatically increased with the addition of salicylic acid (SA); the optimal SA dose was 25 μmol/L for hairy roots. RNA-seq was applied to analyze the transcriptomic changes in hairy roots treated with SA for 24 h in comparison with an untreated control. A total of 3,716, 4,018, and 2,715 differentially expressed transcripts (DETs) were identified in 0 h-vs.-12 h, 0 h-vs.-24 h, and 12 h-vs.-24 h libraries, respectively. KEGG pathway-based analysis revealed that 127 DETs were enriched in “phenylpropanoid biosynthesis.” Of 219 putative unigenes involved in acteoside biosynthesis, 54 were found to be up-regulated at at least one of the time points after SA treatment. Selected candidate genes were analyzed by quantitative real-time PCR (qRT-PCR) in hairy roots with SA, methyl jasmonate (MeJA), AgNO3 (Ag+), and putrescine (Put) treatment. All genes investigated were up-regulated by SA treatment, and most candidate genes were weakly increased by MeJA to some degree. Furthermore, transcription abundance of eight candidate genes in tuberous roots of the high-acteoside-content (HA) cultivar QH were higher than those of the low-acteoside-content (LA) cultivar Wen 85-5. These results will pave the way for understanding the molecular basis of acteoside biosynthesis in R. glutinosa, and can serve as a basis for future validation studies.

Hyperhydricity: underlying mechanisms

The apoplast consists of the cell wall continuum and the intercellular spaces. Flooding of the apoplast is the major causative factor of the hyperhydricity (HH) syndrome. Flooding reduces gas exchange by cells. This leads to anaerobiosis and to accumulation within cells of gases like ethylene. The flooding is caused by the ample availability of water in tissue culture and occurs more on liquid medium and Gelritesolidified medium than on agar-solidified medium. Gelrite causes more HH since medium solidified with Gelrite liquefies, probably because of chelating compounds excreted by plant tissues. Root pressure causes translocation of water from the roots to the apoplast. At the same time, the water that has entered the apoplast cannot easily be removed in vitro by transpiration due to the very high relative humidity in the headspace. When the stomata are forced to close by addition of salicylic acid, transpiration is even more impaired. This results in an increase of HH.

Preparation of Salicylic Acid Loaded Nanostructured Lipid Carriers Using Box-Behnken Design: Optimization, Characterization and Physicochemical Stability.

Nanostructured lipid carriers loaded salicylic acid (NLCs-SA) were developed and optimized by using the design of experiment (DOE). Box-Behnken experimental design of 3-factor, 3-level was applied for optimization of nanostructured lipid carriers prepared by emulsification method. The independent variables were total lipid concentration (X1), stearic acid to Lexol® GT-865 ratio (X2) and Tween® 80 concentration (X3) while the particle size was a dependent variable (Y). Box-Behnken design could create 15 runs by setting response optimizer as minimum particle size. The optimized formulation consists of 10% of total lipid, a mixture of stearic acid and capric/caprylic triglyceride at a 4:1 ratio, and 25% of Tween® 80 which the formulation was applied in order to prepare in both loaded and unloaded salicylic acid. After preparation for 24 hours, the particle size of loaded and unloaded salicylic acid was 189.62±1.82 nm and 369.00±3.37 nm, respectively. Response surface analysis revealed that the amount of total lipid is a main factor which could affect the particle size of lipid carriers. In addition, the stability studies showed a significant change in particle size by time. Compared to unloaded nanoparticles, the addition of salicylic acid into the particles resulted in physically stable dispersion. After 30 days, sedimentation of unloaded lipid carriers was clearly observed. Absolute values of zeta potential of both systems were in the range of 3 to 18 mV since non-ionic surfactant, Tween® 80, providing steric barrier was used. Differential thermograms indicated a shift of endothermic peak from 55°C for α-crystal form in freshly prepared samples to 60°C for β´-crystal form in storage samples. It was found that the presence of capric/caprylic triglyceride oil could enhance encapsulation efficiency up to 80% and facilitate stability of the particles.

The Distribution of Bio-Oil Components with the Effects of Sub/Supercritical Ethanol and Free Radicals during Cellulose Liquefaction

Hydroxyl radicals (HO•) and hydrogen radicals (H•) produced from sub/supercritical ethanol have an obvious contribution on cellulose liquefaction for bio-oil production. Salicylic acid was employed as the HO• trap and CCl4 was employed as the H• trap to investigate the role of HO• and H• on the formation pathways of dominant chemical components in bio-oil during cellulose liquefaction in sub/supercritical ethanol (mostly ketones and esters). The yield of bio-oil decreased from 24.7% to 20.7% with the addition of CCl4, while the bio-oil yield increased from 29.3% to 47.9% with the addition of salicylic acid. Gas chromatography/mass spectrometry results showed that the yields of ketones, esters, and phenols in the bio-oil were 22.3%, 8.8%, and 4.7%, respectively, without salicylic acid or CCl4. The highest yields of esters and phenols increased to 21.6% and 36.9%, respectively, in the presence of salicylic acid. The yield of ketones decreased to 14.1%. Experimental data indicated that the cleavage of C-O-C and C-C bonds in the cornstalk cellulose initially generated many active cellulose fragments. Then, platform chemicals were formed from these fragments through aromatization, isomerization, aldol condensation, Baeyer-Villiger oxidation, and trans-Diels-Alder ring-opening with the redox of HO• and H•.

Effects of pH, dissolved organic matter, and salinity on ibuprofen sorption on sediment.

Ibuprofen is well known as one of the most frequently detected pharmaceuticals and personal care products (PPCPs) in rivers. However, sorption of ibuprofen onto sediment has not been considered in spite of its high K ow (3.5). In this study, the effects of various environmental conditions such as pH (4, 5.3, and 7), the concentrations of dissolved organic matters (0 to 1.0 mM citrate and urea), salinity (0, 10, 20, and 30 part per thousand), and presence of other PPCP (salicylic acid) on ibuprofen sorption were investigated. Linear model mainly fitted the experimental data for analysis. The distribution coefficient (K d) in the linear model decreased from 6.76 at pH 4 to near zero at pH 7, indicating that neutral form of ibuprofen at pH below pKa (5.2) was easily sorbed onto the sediment whereas the sorption of anionic form at pH over pKa was not favorable. To investigate the effect of dissolved organic matters (DOMs) on ibuprofen sorption, citrate and urea were used as DOMs. As citrate concentration increased, the K d value decreased but urea did not interrupt the ibuprofen sorption. Citrate has three carboxyl functional groups which can attach easily ibuprofen and hinder its sorption onto sediment. Salinity also affected ibuprofen sorption due to decrease of the solubility of ibuprofen as salinity increased. In competitive sorption experiment, the addition of salicylic acid also led to enhance ibuprofen sorption. Conclusively, ibuprofen can be more easily sorbed onto the acidified sediments of river downstream, especially estuaries or near-shore environment with low DOM concentration.

Plant Hormone Salicylic Acid Produced by a Malaria Parasite Controls Host Immunity and Cerebral Malaria Outcome.

The apicomplexan parasite Toxoplasma gondii produces the plant hormone abscisic acid, but it is unclear if phytohormones are produced by the malaria parasite Plasmodium spp., the most important parasite of this phylum. Here, we report detection of salicylic acid, an immune-related phytohormone of land plants, in P. berghei ANKA and T. gondii cell lysates. However, addition of salicylic acid to P. falciparum and T. gondii culture had no effect. We transfected P. falciparum 3D7 with the nahG gene, which encodes a salicylic acid-degrading enzyme isolated from plant-infecting Pseudomonas sp., and established a salicylic acid-deficient mutant. The mutant had a significantly decreased concentration of parasite-synthesized prostaglandin E2, which potentially modulates host immunity as an adaptive evolution of Plasmodium spp. To investigate the function of salicylic acid and prostaglandin E2 on host immunity, we established P. berghei ANKA mutants expressing nahG. C57BL/6 mice infected with nahG transfectants developed enhanced cerebral malaria, as assessed by Evans blue leakage and brain histological observation. The nahG-transfectant also significantly increased the mortality rate of mice. Prostaglandin E2 reduced the brain symptoms by induction of T helper-2 cytokines. As expected, T helper-1 cytokines including interferon-γ and interleukin-2 were significantly elevated by infection with the nahG transfectant. Thus, salicylic acid of Plasmodium spp. may be a new pathogenic factor of this threatening parasite and may modulate immune function via parasite-produced prostaglandin E2.