scholarly journals The Biosynthesis of Phenolic Compounds Is an Integrated Defence Mechanism to Prevent Ozone Injury in Salvia officinalis

Antioxidants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1274
Author(s):  
Alessandra Marchica ◽  
Lorenzo Cotrozzi ◽  
Rebecca Detti ◽  
Giacomo Lorenzini ◽  
Elisa Pellegrini ◽  
...  
Keyword(s):  
Plant Defence ◽  
Phenol Oxidase ◽  
Tyrosine Aminotransferase ◽  
Phenylpropanoid Metabolism ◽  
Defence Mechanism ◽  
Ozone Injury ◽  
End Of Treatment ◽  
Oxidative Damage To Proteins ◽  
Induced Changes ◽  
Rosmarinic Acid Synthase

Specialized metabolites constitute a major antioxidant system involved in plant defence against environmental constraints, such as tropospheric ozone (O3). The objective of this experiment was to give a thorough description of the effects of an O3 pulse (120 ppb, 5 h) on the phenylpropanoid metabolism of sage, at both biochemical and molecular levels. Variable O3-induced changes were observed over time among the detected phenylpropanoid compounds (mostly identified as phenolic acids and flavonoids), likely because of their extraordinary functional diversity. Furthermore, decreases in the phenylalanine ammonia-lyase (PAL), phenol oxidase (PPO), and rosmarinic acid synthase (RAS) activities were reported during the first hours of treatment, probably due to an O3-induced oxidative damage to proteins. Both PAL and PPO activities were also suppressed at 24 h from the beginning of exposure, whereas enhanced RAS activity occurred at the end of treatment and at the recovery time, suggesting that specific branches of the phenolic pathways were activated. The increased RAS activity was accompanied by the up-regulation of the transcript levels of genes like RAS, tyrosine aminotransferase, and cinnamic acid 4-hydroxylase. In conclusion, sage faced the O3 pulse by regulating the activation of the phenolic biosynthetic route as an integrated defence mechanism.

scholarly journals 475 Heat Treatments Reduce Irradiation-induced Changes in Phenylpropanoid Metabolism in Grapefruit

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 527A-527
Author(s):  
R.E. McDonald ◽  
W.R. Miller ◽  
T.G. McCollum
Keyword(s):  
Heat Treatment ◽  
Fold Increase ◽  
Heat Treatments ◽  
Maximum Activity ◽  
Phenylpropanoid Metabolism ◽  
Total Phenols ◽  
Citrus Paradisi ◽  
Pal Activity ◽  
Canopy Position ◽  
Induced Changes

Irradiation is being evaluated as a quarantine treatment of grapefruit (Citrus paradisi, Macf.), but it can cause damage to the fruit. We wanted to determine if pre-irradiation heat treatments would improve fruit tolerance to irradiation as they improve tolerance to low-temperature injury. `Marsh' grapefruit were harvested from interior and exterior canopy positions and irradiated at 0 or 1.0 kGy at a dose rate of 0.148 kGy·min-1 before storage for 4 weeks at 10 °C. Following storage, pitting of flavedo tissue was the most evident condition defect noted as a result of irradiation. Pitting was noted on 15% and 27% of irradiated interior and exterior canopy fruit, respectively, whereas there was no pitting on non-irradiated fruit. Temperature conditioning before irradiation decreased the susceptibility of fruit to damage. Pitting was 26%, 19%, and 17% when fruit were held 2 h at 20 (ambient), 38 or 42 °C, respectively. There was a marked increase in phenylalanine ammonia-lyase (PAL) activity following irradiation. Maximum activity (≈18-fold increase) was attained 24 h after irradiation. Irradiation-induced PAL activity was reduced significantly by temperature conditioning at 38 or 42 °C. Exterior canopy fruit flavedo contained higher levels of total phenols, including flavanols and coumarins, compared with interior canopy fruit. The deposition of lignin was not related to canopy position. Neither irradiation nor heat treatment had an effect on total phenols or lignin deposition. It seems that irradiation causes a stress condition in the fruit, which leads to pitting of peel tissue. Heat treatment before irradiation reduced the damaging effects of irradiation.

scholarly journals Vitamin B12 deficiency results in the abnormal regulation of serine dehydratase and tyrosine aminotransferase activities correlated with impairment of the adenylyl cyclase system in rat liver

2008 ◽  
Vol 99 (3) ◽  
pp. 503-510 ◽  
Author(s):  
Shuhei Ebara ◽  
Motoyuki Nakao ◽  
Mayuko Tomoda ◽  
Ryoichi Yamaji ◽  
Fumio Watanabe ◽  
...  
Keyword(s):  
Adenylyl Cyclase ◽  
Rat Liver ◽  
Vitamin B12 Deficiency ◽  
Tyrosine Aminotransferase ◽  
Vitamin B ◽  
Deficient Diet ◽  
Adenylyl Cyclase System ◽  
Serine Dehydratase ◽  
B12 Deficiency ◽  
Induced Changes

The aim of the present study was to elucidate the mechanism of the vitamin B12 deficiency-induced changes of the serine dehydratase (SDH) and tyrosine aminotransferase (TAT) activities in the rat liver. When rats were maintained on a vitamin B12-deficient diet, the activities of these two enzymes in the liver were significantly reduced compared with those in the B12-sufficient control rats (SDH 2·8 (sd 0·56) v. 17·5 (sd 6·22) nmol/mg protein per min (n 5); P < 0·05) (TAT 25·2 (sd 5·22) v. 41·3 (sd 8·11) nmol/mg protein per min (n 5); P < 0·05). In the B12-deficient rats, the level of SDH induction in response to the administration of glucagon and dexamethasone was significantly lower than in the B12-sufficient controls. Dexamethasone induced a significant increase in TAT activity in the primary culture of the hepatocytes prepared from the deficient rats, as well as in the cells from the control rats. However, a further increase in TAT activity was not observed in the hepatocytes from the deficient rats, in contrast to the cells from the controls, when glucagon was added simultaneously with dexamethasone. The glucagon-stimulated production of cAMP was significantly reduced in the hepatocytes from the deficient rats relative to the cells from the control rats. Furthermore, the glucagon-stimulated adenylyl cyclase activity in the liver was significantly lower in the deficient rats than in the controls. These results suggest that vitamin B12 deficiency results in decreases in SDH and TAT activities correlated with the impairment of the glucagon signal transduction through the activation of the adenylyl cyclase system in the liver.

Revisiting the enzymes stored in the laticifers of Carica papaya in the context of their possible participation in the plant defence mechanism

2001 ◽  
Vol 58 (4) ◽  
pp. 556-570 ◽  
Author(s):  
A. El Moussaoui ◽  
M. Nijs ◽  
C. Paul ◽  
R. Wintjens ◽  
J. Vincentelli ◽  
...  
Keyword(s):  
Carica Papaya ◽  
Plant Defence ◽  
Defence Mechanism

scholarly journals Telmisartan Self-Nanoemulsifying Drug Delivery System, Compared With Standard Telmisartan, More Effectively Improves Hepatic Fibrosis in Rats

Dose-Response ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 155932582098219
Author(s):  
Hussam Murad ◽  
Osama Ahmed ◽  
Tawfik Ghabrah ◽  
Mamdooh Gari
Keyword(s):  
Drug Delivery ◽  
Drug Delivery System ◽  
Hepatic Fibrosis ◽  
Delivery System ◽  
White Blood Cells ◽  
Plasma Albumin ◽  
End Of Treatment ◽  
Tnf Α ◽  
High Doses ◽  
Induced Changes

Background: This study was designed to examine effects of telmisartan; an angiotensin receptor blocker; self-nanoemulsifying drug delivery system (SNEDDS) in reversing already-established hepatic fibrosis. Method: Forty rats were given thioacetamide (200 mg/kg, intraperitoneally) twice/week for 8 weeks then divided into 5 groups (n = 8), PC and 4 treated groups. Treatments were given orally for another 2 months as follows: telmisartan low and high doses (TL and TH: 1.8 and 3.6 mg/kg/day) and telmisartan SNEDDS at the same doses (TLS and THS). At end of treatment, blood was obtained and liver was isolated. Results: Rats showed significant elevations of plasma ALT and AST and hepatic IL-6, TNF-α, and MDA, significant reductions of plasma albumin, hepatic GSH, and body weight, and hepatic histopathological damage. All treatments except for TL significantly reversed these thioacetamide-induced changes. THS group showed significant differences from all groups. Regarding ratio of free telmisartan concentration in hepatic homogenate to that of plasma, TH and TLS groups showed non-significant variation between each other while THS group showed significant differences from them. No significant changes were detected in blood pressure, hemoglobin, white blood cells, and platelets. Conclusion: Telmisartan SNEDDS, compared with telmisartan, more effectively reversed chronic hepatic fibrosis with good safety profile.

scholarly journals A Possible Involvement of ACR4, a Receptor Like Kinase, in Plant Defence Mechanism

2012 ◽  
Vol 15 (2) ◽  
pp. 127-130 ◽  
Author(s):  
Jannat E-Zereen ◽  
Gwyneth Ingram
Keyword(s):  
Plant Defence ◽  
Pharmaceutical Journal ◽  
Cuticular Lipid ◽  
Defence Mechanism ◽  
Necrotrophic Pathogen ◽  
Pathogen Challenge ◽  
Receptor Like Kinase ◽  
Receptor Kinases ◽  
Defence Responses

Many developmentally important Receptor Like Kinases (RLKs), also known as receptor kinases have been shown to play independent roles in plant defence. In order to investigate the role of Arabidopsis CRINKLY4 (ACR4) in plant defence mechanism, pathogen challenge experiments were carried out. It was found that ACR4 knockout leaves show reduced susceptibility to the necrotrophic pathogen, Botrytis cinerea. It is therefore possible that the ACR4 receptor might interact with other proteins that regulate specific defence responses. Reduced susceptibility of ACR4 mutant to B. cinerea could also be due to the possible epidermal defect of acr4 leaves. A detailed study of the cuticular lipid composition of acr4 leaves may help ascertain whether epidermal defects in acr4 leaves are responsible for resistance against B. cinerea. DOI: http://dx.doi.org/10.3329/bpj.v15i2.12576 Bangladesh Pharmaceutical Journal 15(2): 127-130, 2012

Low temperature delay and inhibition of a plant defence mechanism: early basal resistance in tobacco

2005 ◽  
Vol 40 (3-4) ◽  
pp. 323-332 ◽  
Author(s):  
E. Besenyei ◽  
P. G. Ott ◽  
Z. Bozsó ◽  
A. Czelleng ◽  
Á. Szatmári ◽  
...  
Keyword(s):  
Low Temperature ◽  
Plant Defence ◽  
Defence Mechanism ◽  
Basal Resistance

Lignin composition and timing of cell wall lignification are involved in Brassica napus resistance to Sclerotinia sclerotiorum stem rot

2021 ◽  
Author(s):  
Andreas von Tiedemann ◽  
Birger Koopmann ◽  
Kerstin Hoech
Keyword(s):  
Cell Wall ◽  
Brassica Napus ◽  
Sclerotinia Sclerotiorum ◽  
Plant Defence ◽  
Phenylpropanoid Pathway ◽  
Stem Rot ◽  
Phenylpropanoid Metabolism ◽  
Sclerotinia Stem Rot ◽  
Cell Wall Modification ◽  
Lignin Deposition

Sclerotinia stem rot (SSR) is an economically and globally significant disease in oilseed rape (Brassica napus L.) caused by the necrotrophic ascomycete Sclerotinia sclerotiorum. This study explored the role of cell wall reinforcement by lignin as a relevant factor for effective plant defence against attack of this pathogen. Expression of key genes in the phenylpropanoid pathway and the induced synthesis of lignin in infected stem tissues were investigated in a study comparing a susceptible (Loras) and a moderately resistant cultivar (Zhongyou 821, ZY821). Data revealed an earlier and more rapid defence activation in ZY821 through up-regulation of transcript levels of genes related to key steps in the phenylpropanoid pathway associated with enhanced lignin deposition in the resistant B. napus genotype. Expression level of BnCAD5, encoding a cinnamyl alcohol dehydrogenase, responsible for conversion of monolignol to lignin, was more rapidly up-regulated in ZY821 than Loras. The similar expression pattern of BnCAD5 and the gene BnF5H, encoding for the ferulate-5-hydroxylase which catalyses the synthesis of syringyl (S) lignin precursors, suggests that BnCAD5 is involved in the S lignin formation. Histological observations confirmed these results, showing an earlier increase of S lignin deposition in the infected resistant genotype. Deposition of guaiacyl (G) lignin was detected in both genotypes and is thus considered a component of basal, cultivar-independent defence response of B. napus to stem rot. The results indicate the importance of cell wall modification for quantitative stem rot resistance by responses in the phenylpropanoid metabolism generating distinct lignin types on different temporal scales.

scholarly journals A Computational Approach to Predict the Regulation of Antioxidant Enzyme, Catalase in the Plant Defence Mechanism

2014 ◽  
Vol 107 (3) ◽  
pp. 30-37
Author(s):  
Michael ImmanuelJesse ◽  
Mohammed Riyaz. S.U. ◽  
Rajamuthuramalingam Rajamuthuramalingam ◽  
Dharanivasan. G ◽  
Kathiravan. K.
Keyword(s):  
Antioxidant Enzyme ◽  
Plant Defence ◽  
Computational Approach ◽  
Defence Mechanism ◽  
Antioxidant Enzyme Catalase

scholarly journals Effect of graphene / metal nanocomposites on the key genes involved in rosmarinic acid biosynthesis pathway and its accumulation in Melissa officinalis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Roya Karimi Soraki ◽  
Mahyar Gerami ◽  
Moazzameh Ramezani
Keyword(s):  
Gene Expression ◽  
Silver Nanoparticle ◽  
Rosmarinic Acid ◽  
Phenylalanine Ammonia Lyase ◽  
Tyrosine Aminotransferase ◽  
Biosynthesis Pathway ◽  
Acid Biosynthesis ◽  
Low Concentration ◽  
Key Genes ◽  
Rosmarinic Acid Synthase

Abstract Background Recently, numerous investigations have been done to study graphene and silver nanoparticle in the fields of agriculture and medicine. In the present study, the green synthesis of nanoparticles with two concentrations (0, 40, 60 mM) and their effect on the molecular and biochemical biosynthesis pathway of rosmarinic acid in a new method, low cost, and safe for the environment has been investigated. The transcript levels of key genes in the rosmarinic acid biosynthesis pathway (Tyrosine aminotransferase, rosmarinic acid synthase, and phenylalanine-ammonia lyase) were studied using real-time quantitative polymerase chain reaction. Then, the rosmarinic acid content was evaluated using HPLC. Results The results showed that a concentration-dependent manner was observed in treated plants. At the biochemical level, the use of nanocomposites at concentration of 40 mM showed higher soluble carbohydrate (37%), flavonoids (21%), total phenol (35%) as well as total protein (47%) compared to the control plants. HPLC results showed that rosmarinic acid content in the treated plants with a low concentration of nanocomposite (40 mM) was more affected than plants treated with a high concentration of nanocomposite (60 mM) (26%) and also compared to other treatments. At the molecular level, the result showed that Tyrosine aminotransferase and rosmarinic acid synthase gene expression was positively correlated with both silver nanoparticle concentrations and nanocomposite treatments, but phenylalanine-ammonia lyase gene expression was positively correlated only with nanocomposite at 40 mM concentration. Conclude It can conclude that the nanocomposite at low concentration is more likely to induce molecular and biochemical parameters. And also, in the rosmarinic acid biosynthesis pathway, the Tyrosine aminotransferase -derived pathway is more efficient than the phenylalanine-ammonia lyase -derived pathway by causing a nano-elicitor. Therefore, it was concluded that studied elicitor at low concentration, can create plants with higher production capacity.

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