Biosynthesis of phenolic acids in tomato plants infected with Agrobacterium tumefaciens

1974 ◽  
Vol 52 (9) ◽  
pp. 2041-2047 ◽  
Author(s):  
Kailash C. Chadha ◽  
Stewart A. Brown

Tomato plants 21 days old were inoculated with Agrobacterium tumefaciens, the causative organism of crown gall, and 72 h later [3-14C]cinnamic or [carboxyl-14C]benzoic acid was administered by wick-feeding to these and to uninfected control plants. After a further 48 h both groups were examined for incorporation of label into phenolic acids. The pattern of incorporation into bound phenolic acids of the controls was in accord with biosynthetic pathways previously demonstrated in normal plants, but qualitative and quantitative divergence from this pattern was observed in the bound phenolic acids of the infected plants. The data suggest interference by the pathogen with β-oxidation of at least two phenylpropanoid acids of the lignification pathway. In infected plants, lowered incorporation of 14C from cinnamic acid into phenylpropanoid acids of the lignification pathway and their β-oxidation products was accompanied by the appearance of labelled o-coumaric acid, consistent with some diversion of cinnamic acid metabolism toward ortho-hydroxylation. Incorporation of 14C from benzoic acid into gentisic and especially salicylic acid of infected plants was much lower than in the controls.

1968 ◽  
Vol 106 (2) ◽  
pp. 507-514 ◽  
Author(s):  
Keith Moore ◽  
P. V. Subba Rao ◽  
G. H. N. Towers

Ammonia-lyase activity for l-phenylalanine, m-hydroxyphenylalanine and l-tyrosine was demonstrated in cell-free extracts of Sporobolomyces roseus. Cultures of this organism converted dl-[ring−14C]phenylalanine and l-[U−14C]tyrosine into the corresponding cinnamic acid. Tracer studies showed that these compounds were further metabolized to [14C]protocatechuic acid. Benzoic acid and p-hydroxybenzoic acid were intermediates in this pathway. Washed cells of the organism readily utilized cinnamic acid, p-coumaric acid, caffeic acid, benzoic acid and p-hydroxybenzoic acid. Protocatechuic acid was the terminal aromatic compound formed during the metabolism of these compounds. The cells of S. roseus were able to convert m-coumaric acid into m-hydroxybenzoic acid, but the latter compound, which accumulated in the medium, was not further metabolized. 4-Hydroxycoumarin was identified as the product of o-coumaric acid metabolism by this organism.


1959 ◽  
Vol 37 (1) ◽  
pp. 537-547 ◽  
Author(s):  
D. R. McCalla ◽  
A. C. Neish

p-Coumaric, caffeic, ferulic, and sinapic acids were found to occur in Salvia splendens Sello in alkali-labile compounds of unknown constitution. A number of C14-labelled compounds were administered to leafy cuttings of salvia and these phenolic acids were isolated after a metabolic period of several hours and their specific activities measured. Cinnamic acid, dihydrocinnamic acid, L-phenylalanine, and (−)-phenyllactic acid were found to be good precursors of the phenolic acids. D-Phenylalanine, L-tyrosine, and (+)-phenyllactic acid were poor precursors. A kinetic study of the formation of the phenolic acids from L-phenylalanine-C14 gave data consistent with the view that p-coumaric acid → caffeic acid → ferulic acid → sinapic acid, and that these compounds can act as intermediates in lignification. Feeding of C14-labelled members of this series showed that salvia could convert any one to a more complex member of the series but not so readily to a simpler member. Caffeic acid-β-C14 was obtained from salvia after the feeding of L-phenylalanine-β-C14 or cinnamic acid-β-C14, and caffeic acid labelled only in the ring was obtained after feeding generally labelled shikimic acid.


2011 ◽  
Vol 78 (3) ◽  
pp. 197-201 ◽  
Author(s):  
Krystyna Skalicka-Woźniak ◽  
Anna Sokołowska-Krzaczek ◽  
Katarzyna Czubkowska

Qualitative and quantitative analysis of phenolic acids present as free and liberated from their conjunction with sugars and alcohols after hydrolysis in <em>Salsola kali</em> L was done, together with comparison of their content in roots and herb. Analysis was conducted by 2D-TLC and HPLC methods. Eleven phenolic acids were identified such as: protocatechuic, caffeic, gentisic, p-coumaric, p-hydroxybenzoic, p-hydroxyphenylacetic, syryngic, vanillic, ferulic, α- and ß-resorcylic. Differences in composition of fraction of free phenolic acids and those liberated after hydrolysis were noticed. The amount of individual compounds were in the range between 0.10±0.04 mg/100 g of dry weight for p-OH-benzoic acid and 6.40±1.75 mg/100 g of dry weight for ferulic acid.


1959 ◽  
Vol 37 (4) ◽  
pp. 537-547 ◽  
Author(s):  
D. R. McCalla ◽  
A. C. Neish

p-Coumaric, caffeic, ferulic, and sinapic acids were found to occur in Salvia splendens Sello in alkali-labile compounds of unknown constitution. A number of C14-labelled compounds were administered to leafy cuttings of salvia and these phenolic acids were isolated after a metabolic period of several hours and their specific activities measured. Cinnamic acid, dihydrocinnamic acid, L-phenylalanine, and (−)-phenyllactic acid were found to be good precursors of the phenolic acids. D-Phenylalanine, L-tyrosine, and (+)-phenyllactic acid were poor precursors. A kinetic study of the formation of the phenolic acids from L-phenylalanine-C14 gave data consistent with the view that p-coumaric acid → caffeic acid → ferulic acid → sinapic acid, and that these compounds can act as intermediates in lignification. Feeding of C14-labelled members of this series showed that salvia could convert any one to a more complex member of the series but not so readily to a simpler member. Caffeic acid-β-C14 was obtained from salvia after the feeding of L-phenylalanine-β-C14 or cinnamic acid-β-C14, and caffeic acid labelled only in the ring was obtained after feeding generally labelled shikimic acid.


2005 ◽  
Vol 71 (12) ◽  
pp. 7974-7979 ◽  
Author(s):  
J. E. Wells ◽  
E. D. Berry ◽  
V. H. Varel

ABSTRACT Ruminant animals are carriers of Escherichia coli O157:H7, and the transmission of E. coli O157:H7 from cattle to the environment and to humans is a concern. It is unclear if diet can influence the survivability of E. coli O157:H7 in the gastrointestinal system or in feces in the environment. Feces from cattle fed bromegrass hay or corn silage diets were inoculated with E. coli O157:H7, and the survival of this pathogen was analyzed. When animals consumed bromegrass hay for <1 month, viable E. coli O157:H7 was not recovered after 28 days postinoculation, but when animals consumed the diet for >1 month, E. coli O157:H7 cells were recovered for >120 days. Viable E. coli O157:H7 cells in feces from animals fed corn silage were detected until day 45 and differed little with the time on the diet. To determine if forage phenolic acids affected the viability of E. coli O157:H7, feces from animals fed corn silage or cracked corn were amended with common forage phenolic acids. When 0.5% trans-cinnamic acid or 0.5% para-coumaric acid was added to feces from silage-fed animals, the E. coli O157:H7 death rate was increased significantly (17-fold and 23-fold, respectively) compared to that with no addition. In feces from animals fed cracked corn, E. coli O157:H7 death rates were increased significantly with the addition of 0.1% and 0.5% trans-cinnamic acid (7- and 13-fold), 0.1% and 0.5% p-coumaric acid (3- and 8-fold), and 0.5% ferulic acid (3-fold). These data suggest that phenolic acids common to forage plants can decrease viable counts of E. coli O157:H7 shed in feces.


2012 ◽  
Vol 62 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Marcin Horbowicz ◽  
Halina Mioduszewska ◽  
Danuta Koczkodaj ◽  
Marian Saniewski

The effect of methyl jasmonate (JA-Me) and phenolic acids: <i>trans</i>-cinnamic acid (<i>t</i>-CA), <i>p</i>-coumaric acid (<i>p</i>-CA), salicylic acid (SA) as well as naringenine (NAR) on growth of seedlings and accumulation of anthocyanins in common buckwheat (<i>Fagopyrum esculentum</i> Moench) were studied. JA-Me and phenolics were applied to growth medium of 4-days etiolated buckwheat seedlings before their exposition to day/night (16h/8h) conditions. The increase of primary roots and hypocotyls length were measured after 3 days of seedling growth in such conditions. At the end of experiment the total anthocyanins contents were measured as well. Methyl jasmonate (JA-Me) and trans-cinnamic acid (<i>t</i>-CA) inhibited growth of the primary root in young buckwheat seedlings, while naringenine (NAR) had a stimulatory influence, and <i>p</i>-coumaric acid had no effect at all. None of investigated phenolics or JA-Me had an effect on the growth of buckwheat hypocotyls, except the mixture of JA-Me and <i>p</i>-coumarcic acid. JA-Me significantly decreased the anthocyanins level in buckwheat hypocototyls, but not in cotyledons. <i>trans</i>-Cinnamic acid, <i>p</i>-coumaric acid and naringenine had no significant influence on the anthocyanin level in hypocotyls and cotyledons of buckwheat seedlings. Simultaneous treatment of buckwheat seedlings with JA-Me and <i>t</i>-CA or <i>p</i>-CA did not change the inhibition of anthocyanins accumulation in buckwheat hypocotyls by JA-Me. In the hypocotyls of buckwheat treated with a mixture of JA-Me and NAR, or SA, a synergistic reduction of anthocyanins was observed.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 54
Author(s):  
Yu-Ming Chu ◽  
Hafiz Muhammad Asif Javed ◽  
Muhammad Awais ◽  
Muhammad Ijaz Khan ◽  
Sana Shafqat ◽  
...  

The photocatalytic pretreatment of lignocellulosic biomass to oxidize lignin and increase biomass stability has gained attention during the last few years. Conventional pretreatment methods are limited by the fact that they are expensive, non-renewable and contaminate the anaerobic digestate later on. The present study was focused to develop a metal-derived photocatalyst that can work with visible electromagnetic spectra light and oxidize commercial lignin liquor. During this project the advanced photocatalytic oxidation of lignin was achieved by using a quartz cube tungsten T3 Halogen 100 W lamp with a laboratory manufactured TiO2-ZnO nanoparticle (nanocomposite) in a self-designed apparatus. The products of lignin oxidation were confirmed to be vanillic acid (9.71 ± 0.23 mg/L), ferrulic acid (7.34 ± 0.16 mg/L), benzoic acid (6.12 ± 0.17 mg/L) and p-coumaric acid (3.80 ± 0.13 mg/L). These all products corresponded to 85% of the lignin oxidation products that were detectable, which is significantly more than any previously reported lignin pretreatment with even more intensity. Furthermore, all the pretreatment samples were supplemented in the form of feedstock diluent in uniformly operating continuously stirred tank reactors (CSTRs). The results of pretreatment revealed 85% lignin oxidation and later on these products did not hinder the CSTR performance at any stage. Moreover, the synergistic effects of pretreated lignin diluent were seen that resulted in 39% significant increase in the methane yield of the CSTR with constant operation. Finally, the visible light and nanoparticles alone could not pretreat lignin and when used as diluent, halted and reduced the methane yield by 37% during 4th HRT.


Author(s):  
Jemma Gibbard ◽  
Eleanor Castracane ◽  
Anna I Krylov ◽  
Robert Continetti

Photoelectron-photofragment coincidence spectroscopy was used to study the dissociation dynamics of the conjugate bases of benzoic acid and p-coumaric acid. Upon photodetachment at 266 nm (4:66 eV) both aromatic carboxylates...


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