Changes in the content of phenolic compounds and IAA-oxidase activity during the growth of tobacco crown gall suspension culture

1990 ◽  
Vol 32 (1) ◽  
pp. 19-27 ◽  
Author(s):  
Zofia Chirek
2014 ◽  
Vol 53 (1) ◽  
pp. 67-75 ◽  
Author(s):  
Zofia Chirek

IAA oxidase activity was determined in several growth phases of a suspension culture of sunflower crown-gall. During the short phase of intensive growth (zero passage - PO) a negative correlation was noted between enzymatic activity and the rate of growth. IAA oxidase activity increased to a certain level is not a factor limiting cell division. For protraction of the phase of intensive growth (first passage - P1), however, a decrease in the activity of this enzyme seems indispensable. IAA oxidase activity in the tested culture is under the control of inhibitors present in the cells and medium. High enzyme inhibition was observed in PO cells during the phase, of intensive growth and in P1 at the beginning and in the middle part of this phase. These results suggest' that the -auxin level determined in earlier studies in sunflower crown-gall culture is controlled by the IAA oxidase set. During the long phase of intensive growth (P1) this control is of negative feedback type.


1975 ◽  
Vol 39 (2) ◽  
pp. 485-490
Author(s):  
Takashi Matsumoto ◽  
Keiko Okunishi ◽  
Koh Nishida ◽  
Masao Noguchi

1984 ◽  
Vol 62 (11) ◽  
pp. 1046-1050 ◽  
Author(s):  
R. N. Chibbar ◽  
R. Cella ◽  
R. B. Van Huystee

Heme is present in an equimolar ratio to the apoprotein in the major cationic fraction of peanut peroxidase. The removal of heme from the holoenzyme does not affect the physicochemical and immunological properties of the apoperoxidase, however peroxidase activity is completely lost. The indoleacetic acid (IAA) oxidase activity of the apoperoxidase is reduced to 1/20 of the original holoenzyme. Both the peroxidase and IAA-oxidase activity could partially be restored in the holoenzyme reconstituted with hemin. It is suggested that heme may also participate in the IAA-oxidase activity possibly by altering the active site.


1979 ◽  
Vol 34 (3-4) ◽  
pp. 200-209 ◽  
Author(s):  
Gudrun Frey-Schröder ◽  
Wolfgang Barz

Abstract Peroxidases from several plants, including horseradish peroxidase, were capable of converting flavonols to the corresponding 2,3-dihydroxyflavanones in presence of H2O2 . Contrastingly, protein extracts from Mentha piperita plants and Mentha arvensis cell suspension cultures perform ed the same enzymatic step in absence of H2O2 , but only with quercetin, not with kaempferol. H2O2-independent, quercetin converting enzymes were isolated and purified from these extracts, and they could be classified in two groups according to the extent of stimulation of the enzyme reaction by H2O2 . Enzymes from group I were stimulated by exogenous H2O2 , and they resembled horse­ radish peroxidase in several aspects. They possessed IAA oxidase activity, but quercetin was the preferred substrate. Enzymes from group II from the plants appeared to be a distinctly different set of enzymes. They were not stimulated by H2O2 , but required molecular oxygen and converted only 3,3′,4′-trihydroxyflavones under aerobic conditions. Also, they showed no Soret-bands and possessed no IAA oxidase activity. These proteins appear to be a new class of enzymes participating in the first step of flavonol degradation in plants.


1997 ◽  
Vol 52 (7-8) ◽  
pp. 426-432 ◽  
Author(s):  
Zuzanna Skrzypek ◽  
Halina Wysokińska

Abstract By repeated selection of pigment portions of tissue the red callus induced from root seed­lings of Penstemon serrulatus Menz. was chosen for suspension culture, which was maintained in Schenk and Hildebrandt medium supplemented with naphthaleneacetic acid (0.2 mg/l), 6-benzylaminopurine (2 mg/l) and sucrose (50 g/l). From the cultured cells eight phenolic compounds were isolated. They were identified as cyanidin 3-O-glucoside, delphinidin 3-O-glucoside, luteolin, luteolin 7-O-glucoside, norartocarpetin 7-O-glucoside, verbascoside, martynoside and leucosceptoside A. The kind of cell line, its age and light irradiation were important factors in flavonoid production, but production of phenylpropanoid glycosides was found to be unaffected by these factors. The phenolic composition found in the cell culture was compared with those in the flowers and leaves of original plants of P. serrulatus.


Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4407 ◽  
Author(s):  
M.A. Morosanova ◽  
A.S. Bashkatova ◽  
E.I. Morosanova

In order to develop a simple, reliable and low cost enzymatic method for the determination of phenolic compounds we studied polyphenol oxidase activity of crude eggplant (S. melongena) extract using 13 phenolic compounds. Catechol, caffeic and chlorogenic acids, and L-DOPA have been rapidly oxidized with the formation of colored products. Monophenolic compounds have been oxidized at a much slower speed. Ferulic acid, quercetin, rutin, and dihydroquercetin have been found to inhibit polyphenol oxidase activity of crude eggplant extract. The influence of pH, temperature, crude eggplant extract amount, and 3-methyl-2-benzothiazolinone hydrazone (MBTH) concentration on the oxidation of catechol, caffeic acid, chlorogenic acid, and L-DOPA has been investigated spectrophotometrically. Michaelis constants values decrease by a factor of 2 to 3 in the presence of MBTH. Spectrophotometric (cuvette and microplate variants) and smartphone-assisted procedures for phenolic compounds determination have been proposed. Average saturation values (HSV color model) of the images of the microplate wells have been chosen as the analytical signal for smartphone-assisted procedure. LOD values for catechol, caffeic acid, chlorogenic acid, and L-DOPA equaled 5.1, 6.3, 5.8 and 30.0 µM (cuvette procedure), 12.2, 13.2, 13.2 and 80.4 µM (microplate procedure), and 23.5, 26.4, 20.8 and 120.6 µM (smartphone procedure). All the variants have been successfully applied for fast (4-5 min) and simple TPC determination in plant derived products and L-DOPA determination in model biological fluids. The values found with smartphone procedure are in good agreement with both spectrophotometric procedures values and reference values. Using crude eggplant extract- mediated reactions combined with smartphone camera detection has allowed creating low-cost, reliable and environmentally friendly analytical method for the determination of phenolic compounds.


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