INFLUENCE OF NON-IONIC SURFACTANTS, AMMONIUM SULPHATE, WATER QUALITY AND SPRAY VOLUME ON THE PHYTOTOXICITY OF GLYPHOSATE

1981 ◽  
Vol 61 (2) ◽  
pp. 391-400 ◽  
Author(s):  
P. A. O’SULLIVAN ◽  
J. T. O’DONOVAN ◽  
W. M. HAMMAN

In field studies, the surfactants Tween 20, X-77 and Triton X-100 enhanced the effectiveness of low glyphosate rates on rape, wheat, oats and barley. In greenhouse studies, Triton X-A Special and Tween 20 enhanced glyphosate phytotoxicity in wild oats and barley. Concentrations of at least 0.5% vol/vol Tween 20 and 0.25% vol/vol Triton X-A Special were required for enhancement of glyphosate phytotoxicity in barley. The surfactants Renex 36, Cittowet Plus and Dupont WK reduced glyphosate phytotoxicity in field and greenhouse studies. Atplus 411F, Surfel and Triton X-114 also reduced glyphosate effectiveness in several field treatments. A number of other surfactants had no significant effects on glyphosate phytotoxicity. Glyphosate was less phytotoxic to barley when applied in tap water (45 ppm Ca++ equivalent) compared to distilled water. With increasing spray volumes, the effectiveness of low rates of glyphosate was reduced and this reduction was more evident in tap than in distilled water. Ammonium sulphate in combination with Agral 90 enhanced glyphosate phytotoxicity in barley.

Weed Science ◽  
1979 ◽  
Vol 27 (1) ◽  
pp. 38-41 ◽  
Author(s):  
P. W. Stahlman ◽  
W. M. Phillips

Several inorganic salts added to the spray solution reduced the herbicidal activity of glyphosate [N-(phosphonomethyl)glycine]. Of the salts tested, iron and aluminum reduced herbicidal activity most. Reductions by calcium and zinc were moderately severe; by magnesium, moderate; by potassium and sodium, none. The reduction in phytotoxicity seems to be caused by cations, but factors other than valence also may be involved.Reduction in phytotoxicity was related to salt concentration and spray volume. Glyphosate at 0.84 kg/ha in 93 to 374 L/ha distilled water killed test plants. Tap water was an equally effective carrier at 93 and 187 L/ha volumes, but was significantly less effective at the 374 L/ha volume. Activity decreased as the molar concentration of CaCl2 increased to 0.01. Herbicidal activity was eliminated at 0.01 M and 374 L/ha; however, concentrations of CaCl2 exceeding 0.04 M reversed the trend and reacted similarly to a 0.005 M solution, which approximates the minimum hardness of most ground waters in Kansas.


Plant Disease ◽  
2002 ◽  
Vol 86 (3) ◽  
pp. 278-281 ◽  
Author(s):  
J. W. Buck ◽  
M. W. van Iersel ◽  
R. D. Oetting ◽  
Y.-C. Hung

Acidic electrolyzed oxidizing (EO) water, generated by electrolysis of a dilute salt solution, recently gained attention in the food industry as a nonthermal method for microbial inactivation. Our objective was to determine if EO water has potential to control foliar diseases in greenhouses. Test fungi suspended in distilled water were combined with EO water (1:9 water:EO water) for various time periods, the EO water was neutralized, and germination was assessed after 24 h. Germination of all 22 fungal species tested was significantly reduced or prevented by EO water. All relatively thin-walled species (e.g., Botrytis, Monilinia) were killed by incubation times of 30 s or less. Thicker-walled, pigmented fungi (e.g., Curvularia, Helminthosporium) required 2 min or longer for germination to be reduced significantly. Dilution of EO water with tap water at ratios of 1:4 and 1:9 (EO:tap water) decreased efficacy against Botrytis cinerea. The presence of Triton X-100 (all concentrations) and Tween 20 (1 and 10%) eliminated the activity of EO water against B. cinerea. EO water did not damage geranium leaf tissue and inhibited lesion development by B. cinerea when applied up to 24 h postinoculation. EO water has a wide fungicidal activity which could facilitate its use as a contact fungicide on aerial plant surfaces and for general sanitation in the greenhouse.


Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4746
Author(s):  
Marcela Sofia Pino ◽  
Michele Michelin ◽  
Rosa M. Rodríguez-Jasso ◽  
Alfredo Oliva-Taravilla ◽  
José A. Teixeira ◽  
...  

Agave bagasse is a residual biomass in the production of the alcoholic beverage tequila, and therefore, it is a promising raw material in the development of biorefineries using hot compressed water pretreatment (hydrothermal processing). Surfactants application has been frequently reported as an alternative to enhance monomeric sugars production efficiency and as a possibility to reduce the enzyme loading required. Nevertheless, the surfactant’s action mechanisms in the enzymatic hydrolysis is still not elucidated. In this work, hot compressed water pretreatment was applied on agave bagasse for biomass fractionation at 194 °C in isothermal regime for 30 min, and the effect of non-ionic surfactants (Tween 20, Tween 80, Span 80, and Polyethylene glycol (PEG 400)) was studied as a potential enhancer of enzymatic saccharification of hydrothermally pretreated solids of agave bagasse (AGB). It was found that non-ionic surfactants show an improvement in the conversion yield of cellulose to glucose (100%) and production of glucose (79.76 g/L) at 15 FPU/g glucan, the highest enhancement obtained being 7% regarding the control (no surfactant addition), using PEG 400 as an additive. The use of surfactants allows improving the production of fermentable sugars for the development of second-generation biorefineries.


1987 ◽  
Vol 65 (1) ◽  
pp. 8-18 ◽  
Author(s):  
Rex K. M. Wong ◽  
Christine P. Nichol ◽  
M. Chandra Sekar ◽  
Basil D. Roufogalis

The efficiency of several nonionic detergents and a homologous series of zwitterionic detergents for the extraction of acetylcholinesterase (EC 3.1.1.7) from bovine erythrocyte membranes was examined. Of the nonionic detergents examined, the polyoxyethylene-based Tweens were the least effective solubilizing agents. Within this series, increasing the length of the saturated fatty acid chain progressively decreased the efficiency of enzyme recovery, while unsaturation in the side chain reversed this trend. In the Lubrol detergents, where the chain length of the alcohol group is variable, an increase in the length of the polyoxyethylene glycol group decreased the recovery of acetylcholinesterase in the solubilized state, without affecting the efficiency of extraction of total erythrocyte protein. As with the other nonionic detergents examined, Triton X-100 and octy1 β-D-glucoside were maximally effective in solubilizing acetylcholinesterase activity at concentrations greater than their respective critical micelle concentrations. In the sulfobetaine (N-alkyldimethylaminopropane sulphonate) zwitterionic detergent series, the longer alkyl chain zwittergents Z 316 and Z 314 were more efficient than the shorter chain length members of the series (Z 310 and Z 312). In contrast to the higher chain length compounds, short chain analogs were maximally effective at or below their critical micelle concentrations. After purification by ion-exchange chromatography and affinity chromatography, the enzyme extracted with the various detergents gave sedimentation coefficients between 6.8S and 7.6S, consistent with a dimeric structure. Acetylcholinesterase could also be efficiently released by 0.2 mM EDTA or 0.5 M NaCl from bovine erythrocyte membranes previously depleted of 70–80% of the membrane lipids by butanol. Nonlinear Arrhenius plots of enzyme activity were found whether acetylcholinesterase was solubilized with Tween 20, Lubrol PX, or Triton X-100. The present work confirms that bovine erythrocyte acetylcholinesterase requires detergents to solubilize it from membranes and that its activity depends on the structure of the amphiphiles used to solubilize the enzyme.


1985 ◽  
Vol 227 (2) ◽  
pp. 405-412 ◽  
Author(s):  
P W Cheng ◽  
W E Wingert ◽  
M R Little ◽  
R Wei

We have characterized a bovine tracheal mucin beta-6-N-acetylglucosaminyltransferase that catalyses the transfer of N-acetylglucosamine from UDP-N-acetylglucosamine to the C-6 of the N-acetylgalactosamine residue of galactosyl-β 1→3-N-acetylgalactosamine. Optimal enzyme activity was obtained between pH 7.5-8.5, at 5mM-MnCl2, and at 0.06-0.08% (v/v) Triton X-100 (or Nonidet P-40), or 0.5-5.0% (v/v) Tween 20. Ba2+, Mg2+ and Ca2+ could partially replace Mn2+, but Co2+, Fe2+, Cd2+ and Zn2+ could not. Sodium dodecyl sulphate, cetylpyridinium chloride, sodium deoxycholate, octyl beta-D-glucoside, digitonin and alkyl alcohols were less effective in enhancing enzyme activity, and dimethyl sulphoxide was ineffective. The apparent Michaelis constants were 1.25 mM for UDP-N-acetylglucosamine, 0.94-3.34 mM for freezing-point-depressing glycoprotein and 0.19 mM for periodate-treated blood-group-A porcine submaxillary mucin. Asialo ovine submaxillary mucin could not serve as the glycosyl acceptor. The structure of the 14C-labelled oligosaccharide obtained by alkaline-borohydride treatment of the product was identified as Gal beta 1→3(Glc-NAc beta 1→6)N-acetylgalactosaminitol by beta-hexosaminidase treatment, gas chromatography-mass spectrometry and 1H-n.m.r. (270 MHz) analysis. The enzyme is important in the regulation of mucin oligosaccharide biosynthesis.


1979 ◽  
Vol 59 (1) ◽  
pp. 93-98 ◽  
Author(s):  
F. A. QURESHI ◽  
W. H. VANDEN BORN

Uptake of 14C-diclofop-methyl {methyl 2-[4-(2,4-dichlorophenoxy)phenoxy propanoate]} by leaves of wild oats (Avena fatua L.) was reduced significantly in the presence of MCPA {[(4-chloro-o-tolyl)oxy]acetic acid]}, especially the dimethylamine formulation. If the herbicides were applied separately, the degree of interference with uptake depended on the extent of overlap of droplets of the two spray preparations on the leaf surface. Spray volume and direction of spray application were important factors in minimizing the mixing of spray droplets on the leaves if the two herbicides were applied separately with a tandem arrangement of two sprayers. Such a sequential application of MCPA ester and diclofop-methyl in a field experiment provided significantly greater wild oat control than could be obtained with a tank mix of the same two herbicides, but the results were not consistent enough to recommend the procedure for practical use.


1988 ◽  
Vol 68 (4) ◽  
pp. 1095-1101 ◽  
Author(s):  
J. A. IVANY

Addition of nonionic surfactants nonylphenoxyl polyethoxy ethanol at 0.1% of total spray volume (vol/vol), tallow amine ethoxylate at 0.5% (vol/vol), or oil concentrate at 1% (vol/vol) to commercially formulated glyphosate applied at 0.25 and 0.5 kg a.i. ha−1 improved control of quackgrass [(Agropyron repens (L.) Beauv.)]. However, the improvement was not sufficient to provide an acceptable level of control of quackgrass. Addition of ammonium sulphate to glyphosate gave significantly greater control of quackgrass at all three rates of glyphosate. In one of the two experiments, control with 0.5 kg a.i. ha−1 of glyphosate was comparable to that of 1.0 kg a.i. ha−1. Addition of either of the three surfactants to the ammonium sulphate and glyphosate combinations did not further enhance control.Key words: Ammonium sulphate, nonylphenoxy polyethoxy ethanol, tallow amine ethoxylate, oil concentrate, Agropyron repens (L.) Beauv.


2017 ◽  
Vol 7 (4) ◽  
pp. 1 ◽  
Author(s):  
Sreedevi Basavaraju ◽  
Chandrasekhar Kathera ◽  
Pramoda Kumari Jasti

The alkaline protease produced by Bacillus cereus UV-15 mutant was purified by precipitation with ammonium sulphate and gel filtration through sephadex G-100. The enzyme has shown to have a molecular weight of 29kDa by SDS polyacrylamide gel electrophoresis. The extracted protease enzyme was purified by 16.64 fold through ammonium sulphate precipitation and chromatography separation in Sephadex G-100. The purified protease had a specific activity of 2915 (U/mg). The zymogram also revealed a clear hydrolytic zone due to proteolytic activity, which coincided with the band obtained with SDS–PAGE. The enzyme was remained active and stable at pH 8-11, with an optimum at pH 10.0. The protease was stable in the temperature ranging from 40°C to 60°C, but gradually decreased at temperature 70°C. The optimum temperature for protease activity was determined at 60°C. The enzyme showed stability towards non-ionic and anionic surfactants, and oxidizing agents. At 1% concentration of Tween-20 and Tween-80, the enzyme retained 78% and 94% relative activity respectively. Alkaline protease retained 95% activity toward 0.5% concentration of the anionic detergent SDS. The enzyme showed compatibility at 50°C with commercial detergents such as Ariel, Surf excel, Rin, wheel, Tide and Nirma. In the presence of Ariel and Rin the enzyme retained about 72 and 75% of the original activity respectively. The supplementation of the enzyme in detergents could improve the cleansing performance towards the blood stains and suggested to be used as a detergent additive. The enzyme also removed goat hide hairs completely after 15 hr of incubation. These characteristics may make the enzyme suitable for several industrial applications, especially in leather industries.


1966 ◽  
Vol 19 (2) ◽  
pp. 445-446 ◽  
Author(s):  
Paul Thomas Young

Further discussion of the Schnorr and Brookshire study of the preference between distilled water and tap water, with comments and suggestions.


2019 ◽  
Vol 230 (12) ◽  
Author(s):  
Agnieszka Dąbska

AbstractThe research goal was to investigate the hydraulic conductivity of compacted lime-softening sludge as a material to be applied to landfill liners. In doing so, the effect of compaction and moulding moisture content on the sludge hydraulic conductivity was assessed. An approximate polynomial k10mean at hydraulic gradients ≥30 for degree of compaction (0.95–1.05) and moulding moisture content (28%–36%) was determined. The results of short-term tap water permeation tests revealed that all hydraulic conductivity values were less than 2.5•10–8 m/s. A lowest hydraulic conductivity of 6.5•10–9 m/s, as well as a corresponding moisture content of 31% were then established. The long-term hydraulic conductivity was measured with tap water, distilled water, NaOH and HCl solutions and municipal waste leachate. The factors of permeating liquids and permeation time significantly affected the initial hydraulic conductivity. The long-term hydraulic conductivity increased for NaOH and HCl solutions and decreased for tap and distilled water. A significant reduction of hydraulic conductivity was observed for leachate permeation. The investigated material met the requirements for the liner systems of inert landfill sites regardless of pH and the limit value for hazardous and non-hazardous waste landfills.


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