scholarly journals Chemical Constituent of β-Glucuronidase Inhibitors from the Root of Neolitsea acuminatissima

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5170
Author(s):  
Chu-Hung Lin ◽  
Hsiao-Jung Chou ◽  
Chih-Chi Chang ◽  
Ih-Sheng Chen ◽  
Hsun-Shuo Chang ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Spectroscopic Analysis ◽  
Methanolic Extract ◽  
Chemical Constituent ◽  
Inhibitory Effect ◽  
Mechanisms Of Action ◽  
Colorectal Carcinogenesis ◽  
Endemic Plant ◽  
Inhibition Ratio

Neolitsea acuminatissima (Lauraceae) is an endemic plant in Taiwan. One new carboline alkaloid, demethoxydaibucarboline A (1), two new eudesmanolide-type sesquiterpenes, methyl-neolitacumone A (2), neolitacumone E (3), and twelve known compounds (4–15) were isolated from the root of Neolitsea acuminatissima. Their structures were elucidated by spectroscopic analysis. Glucuronidation represents a major metabolism process of detoxification for carcinogens in the liver. However, intestinal bacterial β-Glucuronidase (βG) has been considered pivotal to colorectal carcinogenesis. To develop specific bacterial-βG inhibitors with no effect on human βG, methanolic extract of roots of N. acuminatissima was selected to evaluate their anti-βG activity. Among the isolates, demethoxydaibucarboline A (1) and quercetin (8) showed a strong bacterial βG inhibitory effect with an inhibition ratio of about 80%. Methylneolitacumone A (2) and epicatechin (10) exhibited a moderate or weak inhibitory effect and the enzyme activity was less than 45% and 74%, respectively. These four compounds specifically inhibit bacterial βG but not human βG. Thus, they are expected to be used for the purpose of reducing chemotherapy-induced diarrhea (CID). The results suggest that the constituents of N. acuminatissima have the potential to be used as CID relief candidates. However, further investigation is required to determine their mechanisms of action.

Polyphenolic Compounds from Flowers of Hibiscus rosa-sinensis Linn. and their Inhibitory Effect on Alkaline Phosphatase Enzyme Activity in vitro

2011 ◽  
Vol 66 (9-10) ◽  
pp. 453-459 ◽  
Author(s):  
Josline Y. Salib ◽  
Enas N. Daniel ◽  
Mohamed S. Hifnawy ◽  
Shadia M. Azzam ◽  
Iman B. Shaheed ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Methanolic Extract ◽  
Soluble Fraction ◽  
Inhibitory Effect ◽  
Polyphenolic Compounds ◽  
Water Soluble ◽  
Water Soluble Fraction ◽  
Hibiscus Rosa Sinensis ◽  
Phosphatase Enzyme

Graded concentrations (0.1 - 100 mg/mL reaction mixture) of the methanolic extract of the flowers of Hibiscus rosa-sinensis Linn., its water-soluble fraction as well as compounds isolated from this fraction were tested for their inhibitory effect on alkaline phosphatase enzyme activity in vitro. Both the methanolic extract and its water-soluble fraction showed significant inhibitory effects on the enzyme activity in vitro. On screening the activity of the compounds isolated from the water-soluble fraction, its high inhibitory activity was attributed to the presence of quercetin-7-O-galactoside which showed a high potent inhibition of the enzyme activity reaching 100% at 100 mg/mL reaction mixture. Phytochemical investigations of the water-soluble fraction were also carried out and afforded ten polyphenolic compounds including two new natural compounds, namely kaempferol- 7-O-[6´´´-O-p-hydroxybenzoyl-β-D-glucosyl-(1≙6)-β-D-glucopyranoside] and scutellarein-6- O-α-L-rhamnopyranoside-8-C-β-D-glucopyranoside). The chemical structure of the isolated compounds was elucidated on the basis of chemical and spectral data.

Inhibition of the Activities of α2-Plasmin inhibitor (PI) and CI inhibitor (CI-Inh) by the Synthetic Fibrinolytic Agent, 3-Hydroxypropyl Flufenamide (Flu-HPA)

1979 ◽  
Author(s):  
L Miles ◽  
J Burnier ◽  
M Verlander ◽  
M Goodman ◽  
A Kleiss ◽  
...  
Keyword(s):  
Plasminogen Activators ◽  
Inhibitory Effect ◽  
Mechanisms Of Action ◽  
Flufenamic Acid ◽  
Clot Lysis ◽  
Factor Xiia ◽  
Dependent Inhibition ◽  
Normal Human ◽  
Plasmin Inhibitor

Flu-HPA is one of a series of flufenamic acid derivations that enhances plasminogen-dependent clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The influence of Flu-HPA on the inhibition of purified plasmin by purified PI was studied. PI activity was assessed by its inhibition of the clevage of the tripeptide S-2251 (H-D-Val-Leu-Lys-pNA) by plasmin. Flu-HPA was dissolved in DMF or in methonol and preincubated with PI before addition of plasmin. At Flu-HPA concentrations greater than 1mM and up to 60mM, the inhibitory activity of PI was totally lost. The inhibitory effect of normal human plasma on plasmin was also completely abolished at concentrations of Flu-HPA between 2.5 and 40mM. The effect of Flu-HPA on the inhibition of purified plasma kallikrein by purified CI-Inh was also studied. CI-Inh activity was measured by its inhibition of cleavage of the tripeptide Bz-Pro-Phe-Arg-pNA by kallikrein. When Flu-HPA, dissolved in DMF or in methonol, was preincubated with CI-Inh, a concentration dependent inhibition of CI-Inh activity was observed. CI-Inh activity was abolished by concentrations of Flu-HPA greater than 1mM. Flu-HPA also inhibited the activity of CI-Inh on purified Factor XIIa. These observations suggest that this flufenamic acid derivative may enhance fibrinolysis not only by inhibiting PI activity but also by decreasing the inactivation of plasminogen activators by CI-Inh.

Mortality and Inhibitory Effects of Aqueous and Methanolic Extracts of Artemisia annua L. on Biomphalaria pfeifferi (Krauss) and Shedding of Cercariae

2021 ◽  
Vol 42 (1) ◽  
pp. 25-30
Author(s):  
I.M. Ado ◽  
Z.A. Ali ◽  
M.M. Dogara ◽  
K. Abdullahi ◽  
S.A Luka ◽  
...  
Keyword(s):  
Methanolic Extract ◽  
Artemisia Annua ◽  
Scientific Evidence ◽  
Standard Procedure ◽  
Inhibitory Effect ◽  
Control Group ◽  
Inhibitory Effects ◽  
Biomphalaria Pfeifferi ◽  
Artemisia Annua L ◽  
Methanolic Extracts

The search for bioactive plants which can be used as non-conventional anthelmintics has received considerable attention in recent times because of the increasing, worldwide development of resistance to synthetic anthelminthes worm populations. However, scientific evidence to validate the use of raw plants materials remain limited. This study evaluated the mortality and inhibitory effects of the crude aqueous and methanolic extract of Artemisia annua L. against the shedding of cercariae of Schistosoma mansoni from Biomphalaria pfeifferi. The phytochemical screening of the plant was done using standard procedure, after which the mortality effects of the plant extracts and effects on the shedding of cercariae from B. pfeifferi snails were assessed for 24 hour of exposure. Methanolic extract with the highest concentration of 1.77mg/µL had an inhibitory effect of 63.06±1.84 while the least concentration with 0.12mg/µL had 22.41±2.17 inhibitory effect. For the aqueous extract, the highest concentration with 2.73mg/µL had an inhibitory effect of  55.75±1.94 while the least concentration of 0.23mg/µL had 21.80±1.45. Inhibitory effect of cercariae in the snail vector was  concentration dependent, and there was significance difference (P<0.05) between the treatment mean when compared with the control group. This study has shown that this plant material has some inhibitory effect on the shedding of of S. mansoni cercariae and toxicityeffect on the B. pfeifferisnails, and can therefore be used for the control of the disease causing agent as well as the vector. Keywords: Artemisia annua, Inhibitory effects, cercariae, Biomphalaria pfeifferi

Sinapine Esterase I. Characterization of Sinapine Esterase from Cotyledons of Raphanus sativus

1979 ◽  
Vol 34 (9-10) ◽  
pp. 715-720 ◽  
Author(s):  
Gerhild Nurmann ◽  
Dieter Strack
Keyword(s):  
Enzyme Activity ◽  
Esterase Activity ◽  
Raphanus Sativus ◽  
Sinapic Acid ◽  
Inhibitory Effect ◽  
Ph Optimum ◽  
Diisopropyl Fluorophosphate ◽  
E 600 ◽  
Red Radish

Abstract From cotyledons of Raphanus sativus (red radish) an esterase activity which catalyzes the hy­drolysis of sinapine into sinapic acid and choline has been isolated. The enzyme, which has a near absolute specificity, is not analogous with any esterase described in the literature. The reaction has a pH optimum of 8.5 and the apparent Km is 1.95 × 10-5 m. The enzyme is relatively insensi­tive to both physostigmine (eserine) {Ki = 1.73 × 10-4 m) and neostigmine (Ki = 2 .1 3 × 10-4 ᴍ). Diisopropyl fluorophosphate (DFP) showed no inhibition and diethyl p-nitrophenylphosphate (E 600) only a slight inhibitory effect at 10-5 ᴍ, respectively. Choline (10-2 ᴍ) was inhibitory but acetylcholine (10-2 ᴍ) stimulated the enzyme activity.

The chemopreventive effect of 5-demethylnobiletin, a unique citrus flavonoid, on colitis-driven colorectal carcinogenesis in mice is associated with its colonic metabolites

2020 ◽  
Vol 11 (6) ◽  
pp. 4940-4952 ◽  
Author(s):  
Mingyue Song ◽  
Yaqi Lan ◽  
Xian Wu ◽  
Yanhui Han ◽  
Minqi Wang ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Colorectal Carcinogenesis ◽  
Chemopreventive Effect

The inhibitory effect of dietary 5-demethylnobiletin on colitis-driven colorectal carcinogenesis and the potential roles of its colonic metabolites were reported.

scholarly journals Validation of an HPLC Method for the Simultaneous Quantification of Metabolic Reaction Products Catalysed by CYP2C11 Enzymes in Rat Liver Microsomes: In Vitro Inhibitory Effect of Salicylic Acid on CYP2C11 Enzyme

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4294 ◽  
Author(s):  
Salhab ◽  
Naughton ◽  
Barker
Keyword(s):  
High Performance Liquid Chromatography ◽  
Enzyme Activity ◽  
Salicylic Acid ◽  
Liquid Chromatography ◽  
Rat Liver ◽  
High Performance ◽  
Inhibitory Effect ◽  
Metabolic Reaction ◽  
Rat Liver Microsomes

The inhibitory effect of new chemical entities on rat liver P450 marker activities was investigated in a functional approach towards drug development. Treatment of colorectal cancer (CRC) and chemoprevention using salicylic acid has gained a lot of attention, mainly in the prevention of the onset of colon cancer. Thus, an in vitro inhibitory effect of salicylic acid on rat CYP2C11 activity was examined by using high performance liquid chromatography (HPLC). High performance liquid chromatography analysis of a CYP2C11 assay was developed on a reversed phase C18 column (SUPELCO 25 cm × 4.6 mm × 5 µm) at 243 nm using 32% phosphate buffer (pH 3.36) and 68% methanol as a mobile phase. The CYP2C11 assay showed good linearity for all components (R2 > 0.999). Substrates and metabolites were found to be stable for up to 72 hours. Additionally, the method demonstrated good reproducibility, intra- and inter-day precision (<15%), acceptable recovery and accuracy (80%–120%), and low detection (1.3501 µM and 3.2757 µM) and quantitation limit values (4.914 µM and 9.927 µM) for 16α-hydroxytestosterone and testosterone, respectively. Salicylic acid acts reversibly as a noncompetitive (weak) inhibitor with Ki = 84.582 ± 2.67 µM (concentration of inhibitor to cause 50% inhibition of original enzyme activity (IC50) = 82.70 ± 2.67 µM) for CYP2C11 enzyme activity. This indicates a low potential to cause toxicity and drug–drug interactions.

scholarly journals Methanolic Extract of Distemonanthus benthamianus (Caesalpiniaceae) Stem Bark Suppresses Ethanol/Indomethacin-Induced Chronic Gastric Injury in Rats

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Vanessa Mba Matah Marte ◽  
Gilbert Ateufack ◽  
Marius Mbiantcha ◽  
Albert Donatien Atsamo ◽  
Carine Flore Adjouzem ◽  
...  
Keyword(s):  
Methanolic Extract ◽  
Protein Denaturation ◽  
Hematological Parameters ◽  
Mechanisms Of Action ◽  
Male Rats ◽  
Gastric Ulcers ◽  
Gastric Injury ◽  
Ros Production ◽  
Tnf Α ◽  
Anti Inflammatory

Distemonanthus benthamianus (Caesalpiniaceae) is a plant from the Cameroon pharmacopoeia very widely used in the treatment of many pathologies among which are gastrointestinal disorders. The main purpose of this study was to assess the healing properties of gastric ulcer from the methanolic extract of Distemonanthus benthamianus and its mechanisms of action. The healing properties of gastric ulcers (chronic ulcer model induced by ethanol and indomethacin) were evaluated in vivo in adult male rats, while the mechanisms of action were evaluated in vitro by anti-inflammatory assay (protein denaturation, cyclooxygenase, and lipoxygenase assays) and immunomodulatory assay (ROS production (using technical chemiluminescence), cytokine (TNF-α, IL-1β, IL-6) production (using ELISA), proliferation of T cells (using liquid scintillation counter), and cytotoxicity (using MTT assay)). The methanolic extract of Distemonanthus benthamianus inhibited protein denaturation (75.63%) and the activities of cyclooxygenase (78.92%) and 5-lipoxygenase (81.54%). The extract also significantly ( p < 0.001 ) inhibited intracellular and extracellular ROS production and T cell proliferation and reduced significantly ( p < 0.01 , p < 0.001 ) TNF-α, IL-1β, IL-6, and PGE2 production. At all doses (125, 250, and 500 mg/kg), the extract significantly reduces the ulceration index and the area of ulceration and significantly increases the mass of gastric mucus. In addition, the extract significantly decreases the level of MDA, significantly increases the activities of catalase and glutathione, and then improves the hematological parameters in sick animals. Histological micrographs show that in the presence of the extract, there is advanced reepithelialization with recovery of the ulcerated epithelium. Thus, the extract of Distemonanthus benthamianus has healing properties against gastric ulcers which are associated with its anti-inflammatory, immunomodulatory, and antioxidant effects.

scholarly journals Pubinernoid A and Apo-9′-fucoxanthinone, Secondary Metabolites from a Gorgonian Coral Pinnigorgia sp

2016 ◽  
Vol 11 (6) ◽  
pp. 1934578X1601100
Author(s):  
Hsin-Huan Chang ◽  
Yu-Chia Chang ◽  
Wu-Fu Chen ◽  
Tsong-Long Hwang ◽  
Lee-Shing Fang ◽  
...  
Keyword(s):  
Secondary Metabolites ◽  
Spectroscopic Data ◽  
Spectroscopic Analysis ◽  
Inhibitory Effect ◽  
Human Neutrophils ◽  
Gorgonian Coral ◽  
First Report ◽  
Significant Inhibitory Effect ◽  
Animal Source

The structures of pubinernoid A (1) and apo-9′-fucoxanthinone (2), isolated from a gorgonian coral Pinnigorgia sp., were elucidated on the basis of spectroscopic analysis and by comparison of their spectroscopic data with those of known compounds. This is the first report of 1 and 2 from an animal source. Apo-9′-fucoxanthinone (2) displayed a significant inhibitory effect on the release of elastase by human neutrophils, with an IC50 value of 5.75 μM.

Glycoprotein Biosynthesis: Stimulation of N-Acetylglucosaminyltransferase Activity by Cytidiee 5′-Diphosphocholine

1972 ◽  
Vol 50 (10) ◽  
pp. 1082-1093 ◽  
Author(s):  
Sailen Mookerjea
Keyword(s):  
Enzyme Activity ◽  
Phospholipase C ◽  
Inhibitory Action ◽  
Inhibitory Effect ◽  
Nucleotide Sugar ◽  
Inorganic Pyrophosphate ◽  
Golgi Membranes ◽  
Cationic Detergents ◽  
Better Than ◽  
Stimulation Of

The stimulatory effect of CDP-choline on N-acetylglucosaminyltransferase activity is marked in rough microsomes but is almost absent in Golgi-rich membranes or in serum. The marked CDP-choline effect on the enzyme is evident even when the nucleotide–sugar substrate concentration is raised to near saturation. Diglyceride has an inhibitory action on the enzyme which is effectively reversed by further addition of CDP-choline. Of the other different lipid factors tested only CDP-ethanolamine has a stimulatory effect similar to CDP-choline. CDP-choline alone activates the enzyme better than Triton. CDP-choline and Triton, in different combinations of doses, show a marked synergistic effect. Cationic detergents do not activate the enzyme and inorganic pyrophosphate almost completely inhibits the enzyme activity. Phospholipase A has an inhibitory effect in the presence of CDP-choline. Phospholipase C, by itself, stimulates the enzyme activity. In the presence of CDP-choline, a higher concentration of phospholipase C partially abolishes the CDP-choline effect on the enzyme. Phosphorylcholine from labeled CDP-choline is rapidly incorporated into lecithin in the assay system used for measuring N-acetylglucosaminyltransferase activity. Capacity for lecithin synthesis is poor in Golgi membranes. However, lecithin synthesis is stimulated by adding exogenous diglyceride, but CDP-choline plus diglyceride failed to activate N-acetylglucosaminyltransferase in Golgi membranes. Finally, various possibilities have been discussed to explain the mechanism of action of CDP-choline on the enzyme.

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