Gibberellin secreting rhizobacterium, Pseudomonas putida H-2-3 modulates the hormonal and stress physiology of soybean to improve the plant growth under saline and drought conditions

Kang, S.M.,Radhakrishnan, R.,Khan, A.L.,Kim, M.J.,Park, J.M.,Kim, B.R.,Shin, D.H.,Lee, I.J. Gauthier-Villars ; Elsevier Science Ltd 2014 Vol. No.

The physiological changes in tolerant soybean plants under salt and drought stress conditions with Pseudomonas putida H-2-3 were investigated. A bacterial isolate H-2-3 was isolated from soil and identified as Pseudomonas putida H-2-3 by 16S rDNA sequences. The treatment of P. putida H-2-3 significantly increased the length, fresh and dry weight of shoot and chlorophyll content in gibberellins (GAs) deficient mutant Waito-c rice seedlings over the control, it might be the presence of GA<SUB>1</SUB>, GA<SUB>4,</SUB> GA<SUB>9</SUB> and GA<SUB>20.</SUB> The soybean plant growth was retarded in salt (120 mM sodium chloride) and drought (15% polyethylene glycol) stress conditions at 10 days treatments, while P. putida H-2-3 effectively enhanced the shoot length and fresh weight of plants suffered at salt and drought stress. The chlorophyll content was lower in abiotic stress conditions and bacterial inoculant P. putida H-2-3 mitigated the stress effects by an evidence of higher quantity of chlorophyll content in plants exposed to salt and drought. The stress hormonal analysis revealed that individual treatment of P. putida H-2-3, salt and drought significantly enhanced the abscisic acid and salicylic acid content than their control. P. putida H-2-3 applied to salt and drought stressed plants showed a lower level of abscisic acid and salicylic acid and a higher level of jasmonic acid content. Under stress condition induced by salt and drought in plants expressed higher level of total polyphenol, superoxide dismutase and radical scavenging activity and no significant changes in flavonoids. The bio-inoculant, P. putida H-2-3 modulated those antioxidants by declining superoxide dismutase, flavonoids and radical scavenging activity. P. putida H-2-3 induced tolerance against abiotic stress was confirmed by a reduction of Na content in abiotic stressed plants. The results suggest that P. putida H-2-3 application reprograms the chlorophyll, stress hormones and antioxidants expression in abiotic stress affected soybean plant and improves their growth under stress environment.

Novel Ag@TiO₂ nanocomposite synthesized by electrochemically active biofilm for nonenzymatic hydrogen peroxide sensor

Khan, M.M.,Ansari, S.A.,Lee, J.,Cho, M.H. Elsevier 2013 Materials science & engineering. C, Materials for Vol.33 No.8

A novel nonenzymatic sensor for H<SUB>2</SUB>O<SUB>2</SUB> was developed based on an Ag@TiO<SUB>2</SUB> nanocomposite synthesized using a simple and cost effective approach with an electrochemically active biofilm. The optical, structural, morphological and electrochemical properties of the as-prepared Ag@TiO<SUB>2</SUB> nanocomposite were examined by UV-vis spectroscopy, X-ray diffraction, transmission electron microscopy and cyclic voltammetry (CV). The Ag@TiO<SUB>2</SUB> nanocomposite was fabricated on a glassy carbon electrode (GCE) and their electrochemical performance was analyzed by CV, differential pulse voltammetry and electrochemical impedance spectroscopy. The Ag@TiO<SUB>2</SUB> nanocomposite modified GCE (Ag@TiO<SUB>2</SUB>/GCE) displayed excellent performance towards H<SUB>2</SUB>O<SUB>2</SUB> sensing at -0.73V in the linear response range from 0.83μM to 43.3μM, within a detection limit and sensitivity of 0.83μM and ~65.2328+/-0.01μAμM<SUP>-1</SUP>cm<SUP>-2</SUP>, respectively. In addition, Ag@TiO<SUB>2</SUB>/GCE exhibited good operational reproducibility and long term stability.

Enhanced photo-Fenton assisted photocatalytic degradation of atenolol using a novel rGO embedded double Z-scheme nano-heterojunction: Mechanism, kinetics and toxicity studies

M. Raaja Rajeshwari,Asad Syed,Ali H. Bahkali,Abdallah M. Elgorban,M. Kalil Rahiman,Rajender S. Varma,S. Sudheer Khan 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

In this work, rGO-based ternary dual Z-scheme heterojunction (rGO/CuFe2O4/CdS/Bi2S3 QDs) was formulatedfor the effective photo-Fenton assisted photocatalytic degradation of a b-blocker, atenolol. The catalystwas synthesised via a simple co-precipitation/hydrothermal method and was characterized usingXRD, XPS, FT-IR, SEM, TEM, PL, EIS, ESR, Raman and DRS. It exhibited about 76.5% degradation of atenololin 360 min under visible light irradiation with a rate constant of 0.004 min1 wherein the mechanism ofenhanced activity was attributed to the formation of OH, h+ and photo-Fenton reaction; a possible mechanismwas drafted. The intermediates were determined using GC–MS analysis delineating a plausibledegradation pathway, the mineralization of atenolol being confirmed by TOC analysis. The catalyst wasreusable and highly stable up to six cycles of degradation, as affirmed via XRD and XPS analysis. Further, the toxicity of the catalyst has been studied using the root cells of Allium cepa, and the degradedproduct and intermediates were assessed deploying ECOSAR software. Thus, the proposed work haspotential which can be implemented in future for the large-scale purification of wastewater.

Development of an avian influenza virus inactivation evaluation method using dialysis cassette in animal manure and mortality disposal systems

Khan, M.A.,Jeong, K.H.,Ahn, H.,Lee, Y.J.,Kim, E.J.,Glanville, T.D.,Kim, J.H.,Choi, D.Y. Academic Press 2013 Biosystems engineering Vol.114 No.1

This study was conducted to evaluate the performance of dialysis cassettes (DCs) as a virus containment vessel during avian influenza (AI) inactivation research in animal mortality disposal systems. During such work viruses must be contained while simultaneously being exposed to process-specific environmental stressors such as pH change, toxic gases, and heat. Although DCs contain porous membranes that permit diffusion of chemicals, virus retention tests showed that DCs retain AI viruses safely inside. Test data also showed very good exchange of hydrogen ions, CH<SUB>4</SUB>, and CO<SUB>2</SUB> through the membrane. In the case of hydrogen ion exchange, it took only 24 h to reach equilibrium within DCs and the surrounding buffer solution. In addition, gas concentrations inside all DCs reached values similar to those in the environment surround the DCs after 24 h. Based on these results, DCs are effective tools for evaluating virus inactivation within animal manure and mortality disposal systems.

Numerical desirability function for adsorption of methylene blue dye by sulfonated pomegranate peel biochar: Modeling, kinetic, isotherm, thermodynamic, and mechanism study

Ali H. Jawad,Ahmed Saud Abdulhameed,M. A. K. M. Hanafiah,Zeid A. AlOthman,Mohammad Rizwan Khan,S. N. Surip 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.7

Sulfonated pomegranate (Punica granatum) peel biochar (SPPBC) was developed via thermal activation with sulfuric acid (H2SO4) to act as a promising biochar material for the adsorptive removal of toxic cationic dye namely methylene blue (MB) dye from contaminated water. A Box-Behnken design (BBD) and numerical desirability function were adopted to optimize the input adsorption variables (SPPBC dosage, temperature, pH, and contact time). The maximum removal of the MB dye can be accomplished by simultaneous significant interaction between SPPBC dosage with solution pH, SPPBC dosage with time, SPPBC dosage with temperature, solution pH with time, and time with temperature. The numerical desirability function identified the highest MB dye removal (93.9%) can be achieved at the following optimum numerical adsorption conditions: SPPBC dosage 0.18 g, temperature 49 oC, pH 9.7, and time 4.3 h. Equilibrium data were well fitted to the Temkin and Langmuir isotherm models. The maximum recorded adsorption capacity of SPPBC for MB dye adsorption by using Langmuir isotherm model was 161.9mg/g. This research work reveals the possibility of converting lignocellulose pomegranate peel into a renewable and environmentfriendly biochar via a relatively fast acid-activation process with the great potential to be promising adsorbent for removal of MB dye.

Inhibition of sulfide mineral oxidation by surface coating agents: Batch and field studies

Ji, M.K.,Gee, E.D.,Yun, H.S.,Lee, W.R.,Park, Y.T.,Khan, M.A.,Jeon, B.H.,Choi, J. Elsevier Scientific Pub. Co 2012 Journal of hazardous materials Vol.229 No.-

The potential of several surface coating agents to inhibit the oxidation of metal sulfide minerals from Young-Dong coal mine and the Il-Gwang gold mine was examined by conducting laboratory scale batch experiments and field tests. Powdered pyrite as a standard sulfide mineral and rock samples from two mine outcrops were mixed with six coating agents (KH<SUB>2</SUB>PO<SUB>4</SUB>, MgO and KMnO<SUB>4</SUB> as chemical agents, and apatite, cement and manganite as mineral agents) and incubated with oxidizing agents (H<SUB>2</SUB>O<SUB>2</SUB> or NaClO). For the observed time period (8 days), Young-Dong coal mine samples exhibited the least sulfate (SO<SUB>4</SUB><SUP>2-</SUP>) production in the presence of KMnO<SUB>4</SUB> (16%) or cement (4%) while, for Il-Gwang mine samples, the least SO<SUB>4</SUB><SUP>2-</SUP> production was observed in presence of KH<SUB>2</SUB>PO<SUB>4</SUB> (8%) or cement (2%) compared to control. Field-scale pilot tests at the Il-Gwang site also showed that addition of KH<SUB>2</SUB>PO<SUB>4</SUB> decreased SO<SUB>4</SUB><SUP>2-</SUP> production from 200 to 13mgL<SUP>-1</SUP> and it also reduced Cu and Mn from 8 and 3mgL<SUP>-1</SUP>, respectively to <0.05mgL<SUP>-1</SUP> (below ICP-OES detection limits). The experimental results suggested that the use of surface coating agents is a promising alternative for sulfide oxidation inhibition at acid mine drainage sites.

Use of Chemical Treatments to Reduce Tannins and Trypsin Inhibitor Contents in Salseed (Shorea robusta) Meal

Mahmood, S.,Khan, Ajmal M.,Sarwar, M.,Nisa, M.,Lee, W.S.,Kim, S.B.,Hur, T.Y.,Lee, H.J.,Kim, H.S. Asian Australasian Association of Animal Productio 2007 Animal Bioscience Vol.20 No.9

This study investigated the effect of chemical treatments on tannins (condensed and hydrolysable) and on the trypsin inhibitor (TI) activity in salseed meal. Triplicate samples of ground salseed meal (1 kg) were mixed with 820 ml of either distilled water (pH 5.3), 0.67 M acetic acid (pH 2.4), 0.67 M sodium bicarbonate (pH 8.2) or 2% polyvinyl-pyrrolidone (PVP) solution. The material was placed in airtight plastic containers and incubated at $37^{\circ}C$ for 0, 3, 6, 12, 24, 48 and 72 h. Samples of untreated salseed meal which had not been subjected to soaking or incubation were run through the analysis to serve as control. Addition of water, acetic acid, sodium bicarbonate and PVP solutions to salseed meal and subsequent anaerobic incubation at $37^{\circ}C$ significantly reduced chemically detectable tannins. At each incubation time, alkali solution was more effective than its counterparts. The effect of acidic solution on hydrolysable tannin was least among the treatments. All the treatments reduced TI activity of salseed meal. The reduction in TI activity by these treatments was similar and ranged between 80-84%. Treatment time effected a decrease in the contents of antinutritional substances. However, the effect of the treatment with the reagents, even for zero incubation time, was quite pronounced. It may be concluded from the present results that the treatment of salseed meal with sodium bicarbonate (0.67 M) is more effective in reducing hydrolysable and condensed tannin contents than PVP, water and acid solutions. Treatment with sodium bicarbonate solution is more economical and easier to handle than acid and PVP treatments. Incubation of the treated material for 12 h is reasonably effective, economical and safe from any mould growth.

Pinoresinol-4,4'-di-O-β-d-glucoside from Valeriana officinalis root stimulates calcium mobilization and chemotactic migration of mouse embryo fibroblasts

Do, K.H.,Choi, Y.W.,Kim, E.K.,Yun, S.J.,Kim, M.S.,Lee, S.Y.,Ha, J.M.,Kim, J.H.,Kim, C.D.,Son, B.G.,Kang, J.S.,Khan, I.A.,Bae, S.S. G. Fischer 2009 Phytomedicine Vol.16 No.6

Lignans are major constituents of plant extracts and have important pharmacological effects on mammalian cells. Here we showed that pinoresinol-4,4'-di-O-β-d-glucoside (PDG) from Valeriana officinalis induced calcium mobilization and cell migration through the activation of lysophosphatidic acid (LPA) receptor subtypes. Stimulation of mouse embryo fibroblast (MEF) cells with 10μM PDG resulted in strong stimulation of MEF cell migration and the EC<SUB>50</SUB> was about 2μM. Pretreatment with pertussis toxin (PTX), an inhibitor of G<SUB>i</SUB> protein, completely blocked PDG-induced cell migration demonstrating that PDG evokes MEF cell migration through the activation of the G<SUB>i</SUB>-coupled receptor. Furthermore, pretreatment of MEF cells with Ki16425 (10μM), which is a selective antagonist for LPA<SUB>1</SUB> and LPA<SUB>3</SUB> receptors, completely blocked PDG-induced cell migration. Likewise, PDG strongly induced calcium mobilization, which was also blocked by Ki16425 in a dose-dependent manner. Prior occupation of the LPA receptor with LPA itself completely blocked PDG-induced calcium mobilization. Finally, PDG-induced MEF cell migration was attenuated by pretreatment with a phosphatidylinositol 3-kinase (PI3K) inhibitor such as LY294002. Cells lacking downstream mediator of PI3K such as Akt1 and Akt2 (DKO cells) showed loss of PDG-induced migration. Re-expression of Akt1 (but not Akt2) completely restored PDG-induced DKO cell migration. Given these results, we conclude that PDG is a strong inducer of cell migration. We suggest that the pharmacological action of PDG may occur through the activation of an LPA receptor whereby activation of PI3K/Akt signaling pathway mediates PDG-induced MEF cell migration.

Quorum sensing activity of the plant growth-promoting rhizobacterium Serratia glossinae GS2 isolated from the sesame (Sesamum indicum L.) rhizosphere

Jung, B. K.,Khan, A. R.,Hong, S. J.,Park, G. S.,Park, Y. J.,Kim, H. J.,Jeon, H. J.,Khan, M. A.,Waqas, M.,Lee, I. J. UNIV. OF MILAN DEPARTMENT OF FOOD SCIENCE AND MICR 2017 ANNALS OF MICROBIOLOGY Vol.67 No.9

<P>Plant growth-promoting rhizobacteria (PGPR) affect plant growth through various mechanisms, such as indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and biofilm formation. The aim of the study reported here was to isolate and characterize rhizobacteria that produce quorum-sensing signal molecules and other PGPR-related molecules. A biofilm-forming bacterium, GS2, was isolated from the rhizosphere of a sesame plant and subsequently found to produce two quorum-sensing signal molecules that were identified as N-hexanoyl-L-homoserine lactone (m/z 200) and N-octanoyl-L-homoserine lactone (m/z 228) by liquid chromatography-tandem mass spectrometry analysis. The strain was also found to produce IAA (17.2 mu g mL(-1)), gibberellins (113.7 mu g mL(-1)), and ACC deaminase (9.7 mu M alpha-ketobutyrate mg(-1) protein h(-1)). The strain was identified as Serratia glossinae based on a comparison of 16S rRNA gene sequences. Inoculation of the strain promoted growth of a gibberellin-deficient rice dwarf mutant (Waito-C). Different growth attributes, including shoot and root elongation, chlorophyll content, and plant weight could be attributed to the PGPR characteristics of strain GS2. These results suggest that S. glossinae strain GS2 can serve as a microbial agent that improves plant growth.</P>

Melatonin Stimulates the SIRT1/Nrf2 Signaling Pathway Counteracting Lipopolysaccharide (LPS)-Induced Oxidative Stress to Rescue Postnatal Rat Brain

Shah, S. A.,Khan, M.,Jo, M. H.,Jo, M. G.,Amin, F. U.,Kim, M. O. John Wiley Sons Ltd 2017 CNS NEUROSCIENCE AND THERAPEUTICS Vol.23 No.1

<P>Aims: Lipopolysaccharide (LPS) induces oxidative stress and neuroinflammation both in vivo and in vitro. Here, we provided the first detailed description of the mechanism of melatonin neuroprotection against LPS-induced oxidative stress, acute neuroinflammation, and neurodegeneration in the hippocampal dentate gyrus (DG) region of the postnatal day 7 (PND7) rat brain. Methods: The neuroprotective effects of melatonin against LPS-induced neurotoxicity were analyzed using multiple research techniques, including Western blotting, immunofluorescence, and enzyme-linked immunosorbent assays (ELISAs) in PND7 rat brain homogenates and BV2 cell lysates in vitro. We also used EX527 to inhibit silent information regulator transcript-1 (SIRT1). Results: A single intraperitoneal (i.p) injection of LPS to PND7 rats significantly induced glial cell activation, acute neuroinflammation, reactive oxygen species (ROS) production and apoptotic neurodegeneration in hippocampal DG region after 4 h. However, the coadministration of melatonin significantly inhibited both LPS-induced acute neuroinflammation and apoptotic neurodegeneration and improved synaptic dysfunction in the hippocampal DG region of PND7 rats. Most importantly, melatonin stimulated the SIRT1/Nrf2 (nuclear factor-erythroid 2-related factor 2) signaling pathway to reduce LPS-induced ROS generation. The beneficial effects of melatonin were further confirmed in LPS-stimulated BV2 microglia cell lines in vitro using EX527 as an inhibitor of SIRT1. LPS-induced oxidative stress, Nrf2 inhibition, and neuroinflammation are SIRT1-dependent in BV2 microglia cell lines. Conclusion: These results demonstrated that melatonin treatment rescued the hippocampal DG region of PND7 rat brains against LPS-induced oxidative stress damage, acute neuroinflammation, and apoptotic neurodegeneration via SIRT1/Nrf2 signaling pathway activation.</P>