The influence of growth conditions and leaf maturity in relation to the chlorogenic acid stimulation of glycollate oxidase from tobacco leaves

1974 ◽  
Vol 52 (1) ◽  
pp. 209-215 ◽  
Author(s):  
Donald W. De Jong

Glycollate oxidase (glycollate: oxygen oxidoreductase EC. 1.1.3.1) levels in tobacco leaves from plants grown under three different photoperiods and three different temperature regimes were compared. Leaf extracts obtained from mature plants grown at moderate temperatures (25–20C; day/night) and with intermediate day lengths (10 h) showed highest activity. In contrast, peroxidase (EC. 1.11.1.7) was highest in extracts from plants grown at low temperatures and short days while chlorogenic acid oxidase (EC. 1.10.3.1) was highest in leaf extracts from plants grown at high temperatures. Other investigations revealed that old leaves contained consistently lower glycollate oxidase levels than young leaves from the same plant. The addition of chlorogenic acid to the assay medium tended to equalize differences in enzyme activity. Photosynthetic efficiency as determined by O2 evolution (Hill reaction) and photophosphorylation in isolated chloroplasts improved with leaf maturity but this development did not appear to be a direct consequence of low photorespiratory activity. Measurements of the conversion of glycollate-1-14C to 14CO2 by leaf disks under light or dark conditions indicated that chlorogenic acid affects glycollate metabolism in vivo. It is postulated that chlorogenic acid moderates photorespiration by interacting with glycollate oxidase.

Molecules ◽  
2019 ◽  
Vol 24 (12) ◽  
pp. 2289 ◽  
Author(s):  
Magdalena Rutkowska ◽  
Monika Anna Olszewska ◽  
Joanna Kolodziejczyk-Czepas ◽  
Pawel Nowak ◽  
Aleksandra Owczarek

Sorbus domestica leaves are a traditionally used herbal medicine recommended for the treatment of oxidative stress-related diseases. Dry leaf extracts (standardized by LC-MS/MS and LC-PDA) and nine model activity markers (polyphenols), were tested in scavenging assays towards six in vivo-relevant oxidants (O2•−, OH•, NO•, H2O2, ONOO−, HClO). Ascorbic acid (AA) and Trolox (TX) were used as positive standards. The most active extracts were the diethyl ether and ethyl acetate fractions with activities in the range of 3.61–20.03 µmol AA equivalents/mg, depending on the assay. Among the model compounds, flavonoids were especially effective in OH• scavenging, while flavan-3-ols were superior in O2•− quenching. The most active constituents were quercetin, (−)-epicatechin, procyanidins B2 and C1 (3.94–24.16 µmol AA/mg), but considering their content in the extracts, isoquercitrin, (−)-epicatechin and chlorogenic acid were indicated as having the greatest influence on extract activity. The analysis of the synergistic effects between those three compounds in an O2•− scavenging assay demonstrated that the combination of chlorogenic acid and isoquercitrin exerts the greatest influence. The results indicate that the extracts possess a strong and broad spectrum of antioxidant capacity and that their complex composition plays a key role, with various constituents acting complementarily and synergistically.


Author(s):  
Milena Villarini ◽  
Mattia Acito ◽  
Raffaella di Vito ◽  
Samuele Vannini ◽  
Luca Dominici ◽  
...  

(1) Background: Cynara cardunculus L. subsp. scolymus (L.) Hegi, popularly known as artichoke, is an herbaceous plant belonging to the Asteraceae family. Artichoke leaf extracts (ALEs) have been widely used in traditional medicine because of their hepatoprotective, cholagogic, hypoglycaemic, hypolipemic and antibacterial properties. ALEs are also recognized for their antioxidative and anti-inflammatory activities. In this study, we evaluated the cytotoxic, genotoxic, and apoptotic activities, as well as effect on cell growth of ALEs on human colon cancer HT-29 and RKO cells. HT-29 and RKO cells exhibit a different p53 status: RKO cells express the wild-type protein, whereas HT-29 cells express a p53-R273H contact mutant. (2) Methods: Four different ALEs were obtained by sequential extraction of dried artichoke leaves; ALEs were characterized for their content in chlorogenic acid, cynaropicrin, and caffeoylquinic acids. HT-29 and RKO cells were used for in vitro testing (i.e., cytotoxicity and genotoxicity assessment, cell cycle analysis, apoptosis induction). (3) Results: Two out of the four tested ALEs showed marked effects on cell vitality toward HT-29 and RKO tumour cells. The effect was accompanied by a genotoxic activity exerted at a non-cytotoxic concentrations, by a significant perturbation of cell cycle (i.e., with increase of cells in the sub-G1 phase), and by the induction of apoptosis. (4) Conclusions: ALEs rich in cynaropicrin, caffeoylquinic acids, and chlorogenic acid showed to be capable of affecting HT-29 and RKO colon cancer cells by inducing favourable biological effects: cell cycle perturbation, activation of mitochondrial dependent pathway of apoptosis, and the induction of genotoxic effects probably mediated by the induction of apoptosis. Taken together, these results weigh in favour of a potential cancer chemotherapeutic activity of ALEs.


1992 ◽  
Vol 56 (11) ◽  
pp. 1705-1710 ◽  
Author(s):  
Masatsune Murata ◽  
Chiyo Kurokami ◽  
Seiichi Homma

2020 ◽  
Vol 15 (12) ◽  
pp. 1934578X2098143
Author(s):  
Hui Liu ◽  
Hao Chen ◽  
Xiaoli Qin ◽  
Xue Ma ◽  
Zipeng Gong ◽  
...  

Periploca forrestii Schltr ( P. forrestii) is a herb used in traditional Chinese medicine for its anti-rheumatoid arthritis effect. The aim of this study was to compare the pharmacokinetic properties of the 5 active components of this plant: neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isochlorogenic acid C, and periplocin between normal rats and adjuvant-induced arthritis model rats. After the intravenous administration (177.78 mg/kg) of P. forrestii extract, samples were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. Compared with normal rats, the area under the curve [(AUC)(0-t), AUC(0-∞)], mean residence time [(MRT)(0-t), MRT(0-∞)] of neochlorogenic acid-treated rats decreased significantly, and drug clearance (CL) and apparent volume of distribution (V) increased significantly; the V of chlorogenic acid-treated rats decreased significantly, and MRT(0-t) significantly increased; the AUC(0-t) and AUC(0-∞) of cryptochlorogenic acid-treated rats decreased significantly, and CL and V increased significantly; the AUC(0-t) and MRT(0-t) of isochlorogenic acid C-treated rats decreased significantly, and V increased significantly; the AUC(0-t) and AUC(0-∞) of periplocin-treated rats increased significantly, and MRT(0-t), MRT(0-∞), CL, and V decreased significantly in model rats. The disease condition of rheumatoid arthritis in rats had a significant effect on the in vivo pharmacokinetics of P. forrestii after the intravenous administration.


1974 ◽  
Vol 20 (11) ◽  
pp. 1619-1621 ◽  
Author(s):  
S. A. Ghabrial

Unusual cultural changes were observed when several bacterial and yeast strains were grown on a medium containing aqueous extracts of tobacco leaves. In 24–48 h incubation on such a medium, several dark-brown papilla-like structures developed on the surface of normally smooth colonies. Moreover, smaller dark-brown refractile globular bodies were observed in the medium in areas beneath and surrounding the microbial colonies with papilla-like structures. Attempts to demonstrate the viability of these globular bodies failed. The cultural abnormalities observed on tobacco extract medium were unique to this medium since they were not detected in a wide variety of culture media tested. The lowest concentration of tobacco extract (dry wt. basis), which is required for the development of this phenomenon, was determined to be 0.5 mg/ml of medium.


2015 ◽  
Vol 10 (3) ◽  
pp. 562 ◽  
Author(s):  
Fatema Nasrin ◽  
Md. Lukman Hakim

<p class="Abstract">In this study the antidiarrheal activity of ethanolic extracts of the leaves of <em>Mikania cordata</em> and <em>Litsea monopetala</em> was evaluated. Diarrhea was induced in mice by oral administration of castor oil (0.5 mL) 30 min after the administration of the extracts. During a 4 hour study the number of diarrheal feces and percentage inhibition of the extracts (200 and 400 mg/kg body weight) was determined. Loperamide (3 mg/kg body weight) served as standard and belonged to the positive control group. The extracts exhibited potent antidiarrheal activity as well as achieved statistically significant p value (p&lt;0.01 and p&lt;0.05) compared to control group. Among the extracts the highest percentage inhibition of defecation (60%) was recorded for leaf extract (400 mg/kg body weight) of <em>L. monopetala</em>. So, the study corroborates the significant antidiarrheal activity of <em>M. cordata</em> and <em>L. monopetala</em> leaf extracts and raises the demand of further sophisticated investigation.</p><p> </p>


Author(s):  
Rathnasagar K ◽  
Thiyagaraj Anand

Objectives: The activity of two different leaf extracts of Lantana indica and Vitex negundo is tested against the 3rd and 4th instar Culex quinquefasciatus larvae to evaluate the potency of the extracts as a larvicide and to find an ecologically sustainable alternative to chemical insecticides. A bioinformatics screening approach was performed to evaluate the in vivo results.Methods: The obtained larvae’s from nearby water sources were tested with N, N-diethyl-meta-toluamide (DEET) as the positive control which is the commercial chemical mosquito repellent and the solvents used for the respective plant extracts act as the negative control. Petroleum ether (PE), ethyl acetate (EA) and an aqueous (AQ) extract were prepared for both L. indica and V. negundo extracts, and its larvicidal activity was tested. A docking based approach was used to study the inhibitory effect of known active compounds from L. indica and V. negundo against acetylcholine esterase (AChE) and sterol binding protein as targets.Results: On comparing the results between three plants extract for its larvicidal activity, the EA extract of V. negundo and L. indica is found to be potent with a low LC50 value. Further, the docking studies between active compounds of L. indica and V. negundo with AChE and Sterol binding protein as targets showed that the compound tangeritin-1 had a good docking score compared to DEET and could be a natural alternative for larvicidal activity in the mosquito.Conclusion: Individual activity of tangeritin-1 could be further studied with mosquito mortality studies and molecular simulations and develop tangeritin-1 as a potential larvicidal compound for commercial use.


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