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In the course of the Maize Consortium Project, investigations were made on the defence mechanisms employed by maize against various abiotic stress factors (low temperature, cadmium) and on the effects exerted by two compounds (S-methylmethionine, salicylic acid) capable of improving the stress resistance of plants to certain abiotic stresses. Salicylic acid (SA) was found to inhibit the uptake of cadmium (Cd), but caused damage to the roots, including a reduction in the activity of phytochelatin synthase (PCS), which meant that preliminary treatment with SA aggravated the damaging effect of Cd. It was also proved that as the result of 2-day treatment with Cd, there was a continuous rise in the Cd level in the plants, more Cd being accumulated in young leaves than in older ones. The PCS activity increased greatly after 24 hours, both in the leaves and in the roots, declining again after 2 days. The effect of SA was examined in both the hybrids and their parental lines, and the effect of this compound on the intensity of alternative respiration was also investigated. A comparison of chilling tolerance data and antioxidant enzyme activity indicated that these two parameters were not directly correlated to each other, i.e. antioxidant enzyme activity values could not be used to draw reliable conclusions on the chilling tolerance of maize lines and hybrids. With regard to the interaction between alternative respiration and salicylic acid, it was proved that exogenous hydrogen peroxide caused a similar increase in the ratio of alternative respiration to that observed after salicylic acid treatment. Abbreviations: SA, salicylic acid; Cd, cadmium; PCS, phytochelatin synthase; SMM, S-methylmethionine; PCs, phytochelatins; PAR, photosynthetically active radiation; TTC, triphenyl tetrazolium chloride; KCN, potassium cyanide; PSII, 2nd photochemical system; POD, guaiacol peroxidase; APX, ascorbate peroxidase; GR, glutathione reductase

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. 1959 82 70 77 Ghamsari, L., Keyhani, E., Golkhoo, S. (2007) Kinetics properties of guaiacol peroxidase activity in

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. 37 636 642 Amako, A., Chen, K., Asada, K. (1994): Separate assays specific for ascorbate peroxidase and guaiacol peroxidase and for the

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Acta Biologica Hungarica
Authors:
Ivanka Fedina
,
Maya Velitchkova
,
Katya Georgieva
,
Dimitrina Nedeva
, and
H. Çakırlar

., Guruprasad, N. (1998) Modulation of guaiacol peroxidase inhibitor by UV-B in cucumber cotyledons. Plant Sci. 136 , 131–137. Guruprasad N. Modulation of guaiacol peroxidase inhibitor by

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of 4,6-di(tertbutyl)guaiacol, a phenolic lignin model compound, by laccase of Coriolus versicolor. FFBS Letters 236 , 309-311. Aromatic ring cleavage of 4,6-di(tertbutyl)guaiacol, a phenolic lignin model compound, by laccase

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Journal of Thermal Analysis and Calorimetry
Authors:
Teresa Sebio-Puñal
,
Salvador Naya
,
Jorge López-Beceiro
,
Javier Tarrío-Saavedra
, and
Ramón Artiaga

analyzed. Guaiacol was identified along some degradation steps in all cases. This aromatic compound cannot be originated from cellulose or hemicellulose and is a typical degradation product of lignin. It means that a part of the lignins remained with

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sodium acetate buffer (pH 4.5), 0.5 mL substrate solution (46 mM guaiacol), and 0.5 mL culture supernatant ( Singh et al., 1988 ). The activity of Mn-peroxidase (E.C.1.11.1.13) was assessed using a buffered guaiacol solution, 2 mM MnSO 4 , and 0.4 M H 2 O

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of catechol with dimethyl carbonate. Part II. Selective synthesis of guaiacol over alumina loaded with alkali hydroxide . Appl Catal A Gen 166 : 425 – 430 10.1016/S0926-860X(97)00288-3 . 21

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temperatures [ 4 , 5 ]. Another is that the flash pyrolysis of lignin produces syringols, guaiacols, and phenols at high temperatures and mainly simpler gases of H 2 O, CO, CO 2 , CH 4 , and CH 3 OH at both low and high temperatures [ 5 , 6 ]. One will even

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]. A major part of vanillin is synthetically produced from guaiacol or lignin, and thus, it has become accessible for a wide range of use [ 10 ]. Vanillin consists of a phenol ring with an aldehyde-, a methoxy- and a hydroxy-group at specific positions

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