EFFECT OF BENZOIC ACID AND ITS DERIVATIVES ON PLANT METABOLISM: 6- EFFECT OF CHLOROBENZOIC ACID DERIVATIVES ON THE CARBOHYDRATE METABOLISM OF STARVED AND SUCROSE-FED ETIOLATED BARLEY LEAVES

1963 ◽  
Vol 41 (6) ◽  
pp. 939-946 ◽  
Author(s):  
M. I. Naguib

The effects of chlorobenzoic acids on respiration, sucrose absorption, and carbohydrate metabolism of etiolated barley leaves were studied. The results showed that respiration was retarded to the same extent irrespective of position of substitution, in the presence of these substances; inhibition was more pronounced at higher concentrations of chlorobenzoic acids. At low concentrations, o-chlorobenzoic acid enhanced sucrose uptake and p-chlorobenzoic inhibited uptake while at higher concentrations, both compounds inhibited sucrose uptake by etiolated barley leaves.Tissue analysis for carbohydrates showed a decrease in all carbohydrate fractions of treated leaves compared to the control samples. Even the sucrose-fed treated samples showed a carbohydrate content similar to that of the samples starving in distilled water in spite of the variable amounts of sugars absorbed by such samples.These observations, together with excretion of some copper-reducing substances that disappeared after clearing, support the previous suggestion (4) that the tissue carbohydrates were mostly transformed to non-sugar substances that might have been excreted as a result of increased permeability in the presence of the chlorobenzoic acids. This suggestion, together with the possibility of deactivation of the respiratory dehydrogenases, may explain the reduced rates of respiration of the treated samples.

1964 ◽  
Vol 42 (2) ◽  
pp. 197-204 ◽  
Author(s):  
M. I. Naguib

Six-day-old etiolated barley leaves were kept for 24 hours in culture media containing different concentrations of o-, m-, and p-chlorobenzoic acids, in presence or absence of sucrose. CO2 output and sucrose uptake were markedly depressed while the nitrogen excretion was enhanced in presence of 0.01 M concentration of these substances. The three derivatives caused the hydrolysis of a part of the amide nitrogen to ammonia and (or) the proteins to peptides depending on the concentrations of the chemical and position of substitution. The possible explanations of the observed facts are discussed.


2005 ◽  
Vol 68 (9) ◽  
pp. 1895-1899 ◽  
Author(s):  
MANOJ KUMAR MOHAN NAIR ◽  
HANEM ABOUELEZZ ◽  
THOMAS HOAGLAND ◽  
KUMAR VENKITANARAYANAN

The antibacterial effect of low concentrations of monocaprylin on Escherichia coli O157:H7 in apple juice was investigated. Apple juice alone (control) or containing 2.5 mM (0.055%) or 5 mM monocaprylin was inoculated with a five-strain mixture of E. coli O157:H7 at ~6.0 log CFU/ml. The juice samples were stored at 23 or 4°C for 14 or 21 days, respectively, and the population of E. coli O157:H7 was determined on tryptic soy agar plates supplemented with 0.6% yeast extract. At both storage temperatures, the population of E. coli O157:H7 in monocaprylin-supplemented juice samples was significantly lower (P < 0.05) than that in the control samples. The concentration of monocaprylin and the storage temperature had a significant effect on the inactivation of E. coli O157:H7 in apple juice. Monocaprylin at 5 mM was significantly more effective than 2.5 mM monocaprylin for killing E. coli O157:H7 in apple juice. Inactivation of E. coli O157:H7 by monocaprylin was more pronounced in juice stored at 23°C than in the refrigerated samples. Results of this study indicated that monocaprylin is effective for killing E. coli O157:H7 in apple juice, but detailed sensory studies are needed to determine the organoleptic properties of apple juice containing monocaprylin.


2017 ◽  
Vol 23 (3) ◽  
pp. 329
Author(s):  
Ana Maria Oliveira Souza Alves ◽  
Jaianne Francielle Oliveira Santos Pimentel ◽  
Gustavo Ferreira Da Silva ◽  
Nilbe Carla Mapeli ◽  
Ana Maria Mapeli

The species Gerbera jamesonii Adlam has great economic importance in the ornamental sector, due to exuberance of floral stems. However, florists face some challenges such as postharvest handling and difficulty of conservation. Therefore, this study aimed to characterize the non-structural carbohydrate content in different floral stages of G. jamesonii var. Dawn and evaluate the effect of preservative solutions during the postharvest storage of this species. For this purpose, it was quantified TSS, RS and NRS from the seven stages of gerbera stems ontogeny (E1, E2, E3, E4, E5, E6 and E7). The preservative solutions used were: T1) distilled water; T2) citric acid (100 mg L-1); T3) glucose (20 g L-1); T4) gibberellic acid (GA3 , 5 mg L-1); T5) calcium chloride (CaCl2 , 20g L-1) and T6) Sodium Thiosulphate (STS, 20 mM). The effect of preservative solutions were assessed daily, considering the longevity of flowers, variation in the absorption of preservative solution, pH of the solution and fresh mass variation. The experimental design was completely randomized with four replicates. There was a difference in carbohydrate metabolism during floral opening and senescence. In the orange bracts there was a lower TSS content, while in the inflorescences it was observed a reduction in the yellowish, greenish-green and greenish stages. The content of RS increased in the bracts, whereas in the inflorescence there was no difference. The NRS content was higher in the orange bracts, showing lower rates in the inflorescences in yellowish and yellowish greenish stages. The preservative solutions had an impact, on the floral stem longevity, varying according to the solutions used, i.e. CaCl2 and STS reduced the durability of gerbera flower in 9.25 and 11.5 days, respectively, compared to stems kept in distilled water. The glucose solution did not promote a significant difference compared to water. Therefore, we conclude that there is variation in the metabolism of non-structural carbohydrates during the floral development of G. jamesonii var. Dawn and the tested solutions were not effective in promoting postharvest conservation of gerbera.


2017 ◽  
pp. 836-853
Author(s):  
N. Suchkova ◽  
E. Darakas ◽  
J. Ganoulis ◽  
Y. Vergeles

In this work the suitability of several plant species for phytoremediation under natural and artificially installed conditions was studied. Brassica napus, Medicago sativa, Zea mays, Triticum aestivum, and Hordeum vulgare were grown in pots with sewage sludge from Sindos Main WWTP in Thessaloniki and from Sindos Industrial WWTP in Thessaloniki, Greece. The first series of experiments included comparing measurements of various parameters for the above mentioned plants and the sludge to those for control samples (the same plants growing in compost). It was shown that shoot growth was less reduced in T. aestivum and H. vulgare than in the other plant species studied. B. napus had lower germination tax, followed by M. sativa with the lowest germination tax. Generally B. napus, giving less biomass production than Z. mays and T. aestivum, is characterised by a higher ability to accumulate heavy metals like Cd, Cu, Ni, Pb, Zn, Cr, As and Hg. The second series of experiments included comparing measurements of various parameters of B. napus grown in sludge and treated each 7 days with metal solutions of Ni, Zn and Pb containing 10-2mg/l, 10-4mg/l, 10-6mg/l of each metal, to those for control plants treated with double distilled water. Results showed that shoot growth of B. napus were increased at treatments with lower concentrations of metals (10-6 mg/l) and control (treatment with d-distilled water). At the same time uptake of metal ions was increased with the concentration of the solution, i.e. at higher concentrations (10-2 mg/l). It is truly for Pb and Zn, transfer coefficient TC of which (indicates a plant’s potential to concentrate a metal) was quite high 15 % and 7 % correspondingly. It was noticed that B. napus has high ability to accumulate Cr, from the other hand it did not accumulate Ni (at present case).


1999 ◽  
Vol 45 (2) ◽  
pp. 178-184 ◽  
Author(s):  
K A Billingsley ◽  
S M Backus ◽  
O P Ward

Cells of Pseudomonas strain LB400, grown on biphenyl, glucose, or glycerol, transformed polychlorinated biphenyl (PCB) congeners into chlorobenzoic acid (CBA) metabolites. Transformation of the PCB congeners, 2,3-chlorobiphenyl (CBP), 2,2'-CBP, 2,5,4'-CBP, and 2,4,2',4'-CBP, produced the metabolites, 2,3-CBA, 2-CBA, 4-CBA, and 2,4-CBA, respectively. Rates and extents of PCB transformation and metabolite formation were highest with biphenyl-grown cells. Intermediate rates of metabolite production were observed with glycerol-grown cells, and lowest rates of production were found with glucose-grown cells. Regardless of carbon source, the rate of degradation of congeners was faster than the rate of production of CBAs. Relative rates of PCB transformation and metabolite production from different congeners with cells grown on a particular substrate followed the same general order, 2,3-CBA (from 2,3-CBP) > 2-CBA (from 2,2'-CBP) > 4-CBA (from 2,5,4'-CBP) > 2,4-CBA (from 2,4,2',4'-CBP). Pseudomonas strain LB400 appeared unable to grow on any of the chlorobenzoic acids. However, Pseudomonas strain LB400 cells grown on biphenyl appeared capable of degrading 2-CBA and 2,3-CBA but not 4-CBA nor 2,4-CBA. Cells grown on glycerol appeared unable to metabolize any CBAs.Key words: polychlorinated biphenyls, metabolites, Pseudomonas LB400.


1969 ◽  
Vol 47 (10) ◽  
pp. 1579-1583 ◽  
Author(s):  
R. L. Peterson

Root segments of the fern Ophioglossum petiolatum with either an intact root apex or with the apex removed were treated with distilled water (control) or a range of concentrations of kinetin or benzyladenine in aqueous solution. Buds initiated on segments treated with distilled water or low concentrations of cytokinins had an apical meristem consisting of an apical cell with derivatives and a few leaf primordia located immediately beneath an air cavity formed by the lysis of cortical cells of the parent root. There was little cortical proliferation associated with the initiation of these buds. However, application of cytokinins at relatively high concentrations induced considerable proliferation of root tissue and a concomitant organization of numerous apical meristems in this tissue. Each induced meristem was structurally similar to those initiated on control root segments or those treated with low concentrations of cytokinins with the exception that leaf primordia were not as readily visible. Groups of tracheid-like cells were present in the callus-like outgrowths and, in root segments treated with 10.0 mg/l kinetin, large starch-filled parenchyma cells were evident at the periphery of the proliferations.


2013 ◽  
Vol 12 (2) ◽  
pp. 135-143 ◽  
Author(s):  
Cláudio M. D. de Souza ◽  
Cristine E. A. Carneiro ◽  
João Paulo T. Baú ◽  
Antonio C. S. da Costa ◽  
Flávio F. Ivashita ◽  
...  

AbstractIn the present work, the interactions between forsterite-91 with distilled water and forsterite-91 with artificial seawater were studied at two pHs (2.0 and 8.0) using different techniques. A large increase in pH was observed for samples incubated at an initially acidic pH (2.0) due to the dissolution of forsterite-91 in distilled water and artificial seawater. Thus, in acidic hydrothermal vents, an increase in the amount of hydrocarbons and magnetite should be expected due to the release of Fe(II). The pHPZC decreased and the pHIEP increased when forsterite-91 was treated with distilled water and artificial seawater. The ions from the artificial seawater had an effect on zeta potential. Scanning electron microscopy (SEM) images and X-ray diffractograms showed halite in the samples of forsterite-91 mixed with artificial seawater. The presence of halite or adsorption of ions on the surface of forsterite-91 could affect the synthesis of magnetite and hydrocarbons in hydrothermal vents, due to a decrease in the dissolution rates of forsterite-91. The dissolution of forsterite-91 yields low concentrations of Fe(III) and Mn(II) as detected by electron paramagnetic resonance (EPR) spectroscopy. Microanalysis of forsterite-91 showed a higher amount of Mn, with an oxidation that was likely not +II, as Mn in supernatant solutions was only detected by EPR spectroscopy after mixing with artificial seawater at pH 2.0. As Fe(III) and Mn(II) are catalyst constituents of magnetite and manganese oxide, respectively, their presence is important for synthesis in hydrothermal vents. Etch pits were observed only in the forsterite-91 sample mixed with distilled water at pH 8.0. Na, Cl, S, Ca and K were detected in the samples mixed with artificial seawater by SEM–EDS. Si, Mg, Fe and Al were detected in almost all supernatant samples due to forsterite-91 dissolution. Cr was not dissolved in the experiments, thus Cr in the mineral could serve as an effective catalyst for Fischer Tropsch Types (FTT) reactions in hydrothermal vent systems. X-ray diffractograms of the original forsterite-91 also showed peaks arising from zeolites and clinochlore. After the samples were treated with artificial seawater, X-ray diffractograms showed the dissolution of zeolite. Experiments should be performed in the natural environment to verify the potential for zeolites to act as a catalyst in hydrothermal vents.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Blanka Vrchotová ◽  
Petra Lovecká ◽  
Milena Dražková ◽  
Martina Macková ◽  
Tomas Macek

Degradation of chlorobenzoic acids (e.g., products of microbial degradation of PCB) by strains of microorganisms isolated from PCB contaminated soils was assessed. From seven bulk-soil isolates two strains unique in ability to degrade a wider range of chlorobenzoic acids than others were selected, individually and even in a complex mixture of 11 different chlorobenzoic acids. Such a feature is lacking in most tested degraders. To investigate the influence of vegetation on chlorobenzoic acids degraders, root exudates of two plant species known for supporting PCB degradation in soil were tested. While with individual chlorobenzoic acids the presence of plant exudates leads to a decrease of degradation yield, in case of a mixture of chlorobenzoic acids either a change in bacterial degradation specificity, associated with 3- and 4-chlorobenzoic acid, or an extension of the spectrum of degraded chlorobenzoic acids was observed.


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