Bioactivities of Centaurium erythraea (Gentianaceae) Decoctions: Antioxidant Activity, Enzyme Inhibition and Docking Studies

Abstract

Centaurium erythraea is recommended for the treatment of gastrointestinal disorders and to reduce hypercholesterolemia in ethno-medicinal practice. To perform a top-down study that could give some insight into the molecular basis of these bioactivities, decoctions from C. erythraea leaves were prepared and the compounds were identified by liquid chromatography-high resolution tandem mass spectrometry (LC–MS/MS). Secoiridoids glycosides, like gentiopicroside and sweroside, and several xanthones, such as di-hydroxy-dimethoxyxanthone, were identified. Following some of the bioactivities previously ascribed to C. erythraea, we have studied its antioxidant capacity and the ability to inhibit acetylcholinesterase (AChE) and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR). Significant antioxidant activities were observed, following three assays: free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) reduction; lipoperoxidation; and NO radical scavenging capacity. The AChE and HMGR inhibitory activities for the decoction were also measured (56% at 500 μg/mL and 48% at 10 μg/mL, respectively). Molecular docking studies indicated that xanthones are better AChE inhibitors than gentiopicroside, while this compound exhibits a better shape complementarity with the HMGR active site than xanthones. To the extent of our knowledge, this is the first report on AChE and HMGR activities by C. erythraea decoctions, in a top-down analysis, complemented with in silico molecular docking, which aims to understand, at the molecular level, some of the biological effects ascribed to infusions from this plant.

Effect of Food Preparations on In Vitro Bioactivities and Chemical Components of Fucus vesiculosus

“…Some of the small peptides detected also contain benzene ring in the amino acid residues. These aromatic rings may establish pi-pi interactions with the amino acid at the entrance of the active site pocket [35]. In the present study the value obtained for the inhibition of acetylcholinesterase indicates that the algae, when consumed in a meal, like a soup, may accelerate the digestive tract, also avoiding for instance the cholesterol absorption.…”

“…Phlorotannins have in their molecular structure a phloroglucinol moiety, containing an aromatic ring. Compounds containing aromatic rings can show affinity to the enzyme active site because of the presence of Phe residue at the entrance of the enzyme active site [27,35]. Phlorotannins and the small peptides detected in the aqueous extracts can act as AChE inhibitors.…”

“…The ocean samples extracted at 100 °C and purified by SPE was the extract with a higher antioxidant activity (76.54% ± 0.17) followed by the Tagus samples extracted with the same conditions (41.98% ± 0.55). The results present in Figure 4 demonstrate that although the antioxidant activity even in the best situation is lower than the standard like butylated hydroxytoluene (BHT), whose IC50 is 15.7 ug/mL [35,36], it would be The water extract obtained from the ocean samples at 100 • C, seem to be essentially constituted by large aggregates of cubic and parallelepiped-shaped crystals of diverse sizes (Figure 4a,b), while the capsules extract obtained at the same conditions appeared as a fibrous framework formed by rosette aggregates made by irregular long-shaped particles of different sizes (Figure 4c,d).…”

“…Comparing with other type of aqueous extracts like those obtained from medicinal plants, these aqueous extracts are much more active than most of the extracts containing also phenolic compounds [25,30]. Nevertheless, both extracts are far less potent than the standard galantamine that has an IC50 of 0.14 µg/mL [35], which means that when consumed it will not affect strongly the intestinal motility as the drug might do [37]. approximately 60 ug/mL, value similar to those obtained in infusions from medicinal plants [30].…”

Ultrasound Assisted Extraction of Phenolic Compounds from a Jujube By-Product with Valuable Bioactivities

“…where I is the percent inhibition of acetylcholinesterase, Vsamples the initial velocity of the extract containing reaction, and Vcontrols the initial velocity of the control reaction. The inhibition of the enzymatic activity of 3-hydroxy-3-methylglutaryl reductase (HMGR) was measured using the oxidation of nicotinamide adenine dinucleotide phosphate hydrate (NADPH) in triplicate [37]. Briefly, at 0, 1, 2, 4, and 6 min, aliquots were removed and then the reaction was stopped by adding methanol (50%).…”