GC-MS analysis of metabolites from soxhlet extraction,ultrasound-assisted extraction and supercritical fluid extraction of Salacca zalacca flesh and its alpha-glucosidase inhibitory activity

Abstract

Different extraction processes were employed to extract bioactive metabolites from Salacca zalacca flesh by a range of aqueous and organic solvents. The highest extraction yield was obtained by 50% ethanol extract of SE (73.18?±?4.35%), whereas SFE_1 showed the lowest yield (0.42?±?0.08%). All extracts were evaluated for in vitro α-glucosidase inhibitory activity, measured by their IC₅₀ values in comparison to that of quercetin, the positive control (IC₅₀ = 2.7?±?0.7?μg/mL). The lowest α-glucosidase inhibitory activity was indicated by water extract of SE (IC₅₀ = 724.3?±?42.9?μg/mL) and the highest activity was demonstrated by 60% ethanol extract by UAE (IC₅₀ = 16.2?±?2.4?μg/mL). All extracts were analysed by GC-MS and identified metabolites like carbohydrates, fatty acids, organic acids, phenolic acids, sterols and alkane-based compounds etcetera that may possess the potential as α-glucosidase inhibitor and may attribute to the α-glucosidase inhibitory activity.     

Ligand fishing and identification of acetylcholinesterase inhibitors in Mahonia bealei (Fort.) Carr. using high performance liquid chromatography-mass spectrometry

Abstract

A fishing platform was developed using immobilized capillary enzyme reactors in combination with liquid chromatography-mass spectrometry (LC-MS) to fish acetylcholinesterase inhibitor (AChEI) from Mahonia bealei (Fort.) Carr. (M. bealei) extract. Four potential AChEIs (columbamine, jatrorrhizine, berberine, and palmatine) were successfully screened out and identified. Their AChE inhibitory activities were further verified by an in vitro assay with IC₅₀ values of 0.93?±?0.12?μg/mL (columbamine), 3.50?±?0.15?μg/mL (jatrorrhizine), 2.51?±?0.12?μg/mL (berberine), and 1.52?±?0.13?μg/mL (palmatine). A synergy study of these AChEIs was subsequently investigated. In comparison with the IC₅₀ value of M. bealei extract (IC₅₀=0.83?±?0.21?μg/mL), it can be stated that M. bealei extract is much more active than any single AChEI. Thereafter, the determination of these four alkaloids were investigated and AChE inhibitory effect were compared in terms of the extract and corresponding contents of these four alkaloids. The inhibitory effects of extract at each concentration were stronger than four alkaloids mixture. The results demonstrated that not the four AChEI mixture cause the synergistic effect but rather than the concentrations or ratios of these AChEIs play a vital role in their synergy study.     

Evaluation of the cytotoxicity on breast cancer cell of extracts and compounds isolated from Hyptis pectinata (L.) poit

Abstract

Hyptis pectinata is a herb popularly used in Brazil for the treatment of inflammations, pain, bacterial infections and cancer. In the present study, inflorescences (MPIn), leaves (MPL), branches (MPB), root (MPR) extracts and three compounds isolated from MPIn were assayed against breast tumor cell lines. The structures of the three compounds (pectinolide J, hyptolide and pectinolide E) were determined by means of spectroscopic analysis. Pectinolide J was isolated for the first time. The MPIn, MPL and MPR exhibited specific antiproliferative activity on tumor cell lines when compared to normal cell lines with IC₅₀ of 52.01?±?0.64, 45.91?±?0.02?μg/mL and 82.84?±?0.03?μg/mL, respectively. Although the isolated substances did not present good antiproliferative activity, when the three were associated, a greater biological effect was observed, suggesting a synergistic effect. Hyptolide (5.6?±?0.4?μg/mL) showed IC₅₀ sufficiently low to be considered as a drug prototype.     

Antileishmanial diterpenoid alkaloids from Aconitum spicatum (Bruhl) Stapf

The crude extracts of tubers of Aconitum spicatum (Bruhl) Stapf were investigated for in vitro antileishmanial activity against Leishmania major. The dichloromethane extract at pH 2.5 showed antileishmanial activity with IC₅₀ value of 27.10 ± 0.0 μg/mL. Chromatographic purification of the dichloromethane extract led to isolation of three C-19 norditerpenoid alkaloids indaconitine (1), chasmaconitine (2) and ludaconitine (3). Compounds 3 and 2 showed antileishmanial activity with IC₅₀ = 36.10 ± 3.4 and 56.30 ± 2.1 μg/mL, respectively. Compound 1 was less effective (IC₅₀ > 100 μg/mL). The cytotoxicity of compounds 1, 2 and 3 studied against MCF7, HeLa and PC3 cancer cell lines and 3T3 normal fibroblast cell line did not show cytotoxicity at 30 μM.     

Urease inhibitory profile of extracts and chemical constituents of Pistacia atlantica ssp. cabulica Stocks

The current study was designed to evaluate the urease inhibitory profile of extract and fractions of Pistacia atlantica ssp. cabulica Stocks followed by bioactivity-guided isolated compounds. The crude extract was found significantly active with urease inhibitor (95.40% at 0.2 mg/mL) with IC₅₀ values of 32.0 ± 0.28 μg/mL. Upon fractionation, ethyl acetate fraction displayed 100% urease inhibition with IC₅₀ values of 19.9 ± 0.51 μg/mL at 0.2 mg/mL. However, n-hexane and chloroform fractions exhibited insignificant urease inhibition. Similarly, the isolated compound, transilitin (1) and dihydro luteolin (2) demonstrated marked urease attenuation with 95 and 98% respectively, at 0.15 mg/mL. Both the isolated compounds showed marked potency with IC₅₀ values of 8.54 ± 0.54 and 9.58 ± 2.22 μg/mL, respectively. In short, both the extract and fractions and isolated compounds showed marked urease inhibition and thus a useful natural source of urease inhibition.     

Chemical constituents of essential oil of endemic Rhanterium suaveolens Desf. growing in Algerian Sahara with antibiofilm,antioxidant and anticholinesterase activities

Twenty compounds were detected in the essential oil of Rhanterium suaveolens representing 98.01% of the total oil content. Perillaldehyde (45.79%), caryophyllene oxide (24.82%) and β-cadinol (5.61%) were identified as the main constituents. In β-carotene–linoleic acid assay, both the oil and the methanol extract exhibited good lipid peroxidation inhibition activity, with IC₅₀ values of 17.97 ± 5.40 and 11.55 ± 3.39 μg/mL, respectively. In DPPH and CUPRAC assays, however, the methanol extract exhibited a good antioxidant activity. The highest antibiofilm activity has been found 50.30% against Staphylococcus epidermidis (MU 30) at 20 μg/mL for essential oil and 58.34% against Micrococcus luteus (NRRL B-4375) at 25 mg/mL concentration for methanol extract. The in vitro anticholinesterase activity of methanol extract showed a moderate acetylcholinesterase inhibitory (IC₅₀ = 168.76 ± 0.62 μg/mL) and good butyrylcholinesterase inhibitory (IC₅₀ = 54.79 ± 1.89 μg/mL) activities. The essential oil was inactive against both enzymes.     

Synthesis,characterization, and hypoglycemic efficacy of nitro and amino acridines and 4-phenylquinoline on starch hydrolyzing compounds: an in silico and in vitro study

α-Amylase and α-Glucosidase are important therapeutic targets for type II diabetes. The present focus of our study is to elucidate the hypoglycemic activity of novel compounds through in vitro and in silico studies. Here, we synthesized the nitro acridines (3a–3c), amino acridines (4a–4c), and nitro phenylquinoline (3d) and amino phenylquinoline (4d) using a multi-step reaction protocol in good yields. All the above derivatives were screened for molecular docking, α-Amylase and α-Glucosidase inhibitory activities utilizing acarbose as standard drug. In silico studies were performed to explore the binding ability of compounds with the active site of α-Amylase and α-Glucosidase enzymes. The in vitro antihyperglycemic report of 3c exhibits the maximum inhibitory activity with IC₅₀ values of 200.61?±?9.71 μmol/mL and 197.76?±?8.22 μmol/mL against α-Amylase and α-Glucosidase, respectively. Similarly, the compound 3a exhibits IC₅₀ values of 243.78?±?13.25 μmol/mL and 296.57?±?10.66 μmol/mL, and 4c exhibits IC₅₀ values of 304.28?±?3.51 μmol/mL and 278.86?±?3.24 μmol/mL with a significant p?<?0.05 in both enzyme inhibitions. In addition, the presence of diverse functional moieties in synthesized compounds may provide a strong inhibitory action against the abovementioned enzymes compared with standard acarbose inhibition (IC₅₀, 58.74?±?3.68 μmol/mL and 49.39?±?4.94 μmol/mL). Also, the docking studies provided an excellent support for our in vitro studies. The outcome of these studies recommends that the tested compounds might be treated as potential inhibitors for the starch hydrolyzing enzymes in type II diabetes.

     

Bioactivity and chemical characterisation of Lophostemon suaveolens – an endemic Australian Aboriginal traditional medicinal plant

Lophostemon suaveolens is a relatively unexplored endemic medicinal plant of Australia. Extracts of fresh leaves of L. suaveolens obtained from sequential extraction with n-hexane and dichloromethane exhibited antibacterial activity in the disc diffusion and MTT microdilution assays against Streptococcus pyogenes and methicillin sensitive and resistant strains of Staphylococcus aureus (minimum bactericidal concentration < 63 μg/mL). The dichloromethane extract and chromatographic fractions therein inhibited nitric oxide in RAW264.7 murine macrophages (IC₅₀ 3.7–11.6 μg/mL) and also PGE₂ in 3T3 murine fibroblasts (IC₅₀ 2.8–19.7 μg/mL). The crude n-hexane, dichloromethane and water extracts of the leaves and chromatographic fractions from the dichloromethane extract also showed modest antioxidant activity in the ORAC assay. GC–MS analysis of the n-hexane fraction showed the presence of the antibacterial compounds aromadendrene, spathulenol, β-caryophyllene, α-humulene and α-pinene and the anti-inflammatory compounds β-caryophyllene and spathulenol. Fractionation of the dichloromethane extract led to the isolation of eucalyptin and the known anti-inflammatory compound betulinic acid.     

Comparative study of the phenolic profile,antioxidant and antimicrobial activities of leaf extracts of five Juniperus L. (Cupressaceae) taxa growing in Turkey

Abstract

The purpose of this study was to conduct a comparative evaluation of some biological properties of methanol and water extracts of leaves of five Juniperus taxa growing in Turkey: J. communis L. var. communis (Jcc), J. communis L. var. saxatilis Pall. (Jcs), J. drupacea Labill. (Jd), J. oxycedrus L. subsp. oxycedrus (Joo), J. oxycedrus L. subsp. macrocarpa (Sibth. & Sm.) Ball. (Jom). The antioxidant properties were examined in vitro; both in the DPPH and in the reducing power tests, Joo methanol extract resulted the most active (IC₅₀?=?0.09?±?0.01mg/mL and ASE/mL?=?2.56?±?0.06). In the TBA assay, Jcs methanol extract exhibited the highest activity (IC₅₀?=?4.39?±?0.47?μg/mL). The extracts displayed bacteriostatic activity against Staphylococcus aureus, and Jd methanol extract resulted the most effective (MIC?=?19.53?μg/mL); no effect on the S. aureus biofilm formation was observed. The extracts resulted non-toxic in the Artemia salina lethality bioassay. Finally, the phenolic profile of the methanol extracts was characterized by HPLC-PDA/ESI-MS.     

Inula viscosa (L.) Aiton leaves and flower buds: Effect of extraction solvent/technique on their antioxidant ability,antimicrobial properties and phenolic profile

Abstract

This study was designed to establish the most effective solvent/technique for extracting antioxidant phytoconstituents from leaves and flower buds of Inula viscosa (L.) Aiton (Asteraceae) grown wild in Morocco. Maceration and hot extraction with methanol or water and Soxhlet ethanol extraction were utilized. The antioxidant potential was evaluated in vitro by DPPH, reducing power, and ferrous ions chelating activity assays. I. viscosa leaf and flower bud extracts displayed the strongest effect in the DPPH test, being the Soxhlet ethanol the most active ones (IC₅₀ = 54.24?±?0.21?μg/mL and 39.77?±?0.23?μg/mL); thus, they were selected for further investigations. The antimicrobial efficacy of the Soxhlet ethanol extracts against ATCC and food isolates strains was assayed; the leaf extract showed the best activity, and Candida albicans was the most sensitive strain (MIC = 125?µg/mL). The extracts resulted non-toxic against Artemia salina. Among the phenolics characterised by HPLC-PDA-ESI-MS, hispidulin hexoside, patuletin and spinacetin were identified for the first time.     

A contribution to pharmaceutical biology of freshwater sponges

In vitro anti-tumour and anti-radical activities of the acetone extract of the freshwater sponge Ochridaspongia rotunda were the subject of this study. The extract was found to be highly cytotoxic to human lung tumour cell line A-549 reaching IC₅₀ value of 5.01 ± 0.21 μg/mL. Indeed, it displayed only 2-fold less anti-tumour activity than doxorubicin (IC₅₀ value 2.42 ± 0.13 μg/mL) used as a positive control. The same extract was also found to be almost 37-fold more selective against A-549 vs. MRC-5 (normal) lung cells, in difference to weak selectivity of doxorubicin (less than 3-fold). Its profound anti-DPPH radical activity comparable to that of quercetin (IC₅₀ values 3.68 ± 0.19 and 3.14 ± 0.09 μg/mL, respectively) coupled with no signs of genotoxicity in the comet assay (MRC-5 cell line, vs. doxorubicin) has actually implicated the importance of this animal bioresource in searching for pharmaceutically useful bioactive compounds of natural origin.     

Extract from Eugenia punicifolia is an Antioxidant and Inhibits Enzymes Related to Metabolic Syndrome

The present study aimed to investigate in vitro biological activities of extract of Eugenia punicifolia leaves (EEP), emphasizing the inhibitory activity of enzymes related to metabolic syndrome and its antioxidant effects. The antioxidant activity was analyzed by free radicals scavengers in vitro assays: DPPH·, ABTS^·+, O₂ ^·?, and NO· and a cell-based assay. EEP were tested in inhibitory colorimetric assays using α-amylase, α-glucosidase, xanthine oxidase, and pancreatic lipase enzymes. The EEP exhibited activity in ABTS^·+, DPPH·, and O₂ ^·? scavenger (IC₅₀?=?10.5?±?1.2, 28.84?±?0.54, and 38.12?±?2.6 μg/mL), respectively. EEP did not show cytotoxic effects, and it showed antioxidant activity in cells in a concentration-dependent manner. EEP exhibited inhibition of α-amylase, α-glucosidase, and xanthine oxidase activities in vitro assays (IC₅₀?=?122.8?±?6.3; 2.9?±?0.1; 23.5?±?2.6), respectively; however, EEP did not inhibit the lipase activity. The findings supported that extract of E. punicifolia leaves is a natural antioxidant and inhibitor of enzymes, such as α-amylase, α-glucosidase, and xanthine oxidase, which can result in a reduction in the carbohydrate absorption rate and decrease of risks factors of cardiovascular disease, thereby providing a novel dietary opportunity for the prevention of metabolic syndrome.     

Anti-hydroxyl radical activity,redox potential and anti-AChE activity of Amanita strobiliformis polysaccharide extract

This study outlines antioxidant and anti-AChE activities of the polysaccharide (PSH) extract from the mushroom species Amanita strobiliformis. Both the presence of α and ß glucans within the aforementioned extract was recorded. PSH extract displayed a profound scavenging activity of OH radicals (IC₅₀ value, 11.86 ± 0.59 μg/mL) and high potential for reduction of Fe³⁺ ions (174.11 ± 8.70 mg eq. AA/g d.w.) being almost 48- and 5-fold more effective than mannitol and butylated hydroxytoluene used as a positive control, respectively. Compared with galanthamine (0.001 μg), the same extract exhibited a moderate anti-AChE activity (10 μg) in solid. Since purified PSH extract exhibited higher bioactivity (IC₅₀ value 7.27 ± 0.31 μg/mL, 197.68 ± 9.47 mg eq. AA/g d.w. and 0.1 μg, respectively), it can be predominantly ascribed to the polysaccharide compounds. A. strobiliformis PSH extract may be considered as a promising resource of potent bioactive polysaccharides of natural origin successfully addressing both oxidative stress and lack of acetylcholine.     

Antioxidant,cholinesterase inhibition activities and essential oil analysis of Nelumbo nucifera seeds

Nelumbo nucifera seeds’ essential oil (EO), crude extract and subsequent fractions were evaluated for their DPPH, ABTS and superoxide anion-free radical scavenging and cholinesterase inhibitory activities. The ethyl acetate fraction and EO showed outstanding antioxidant activities with IC₅₀ values of 191, 450 μg/mL (DPPH), 123, 221 μg/mL (ABTS) and 69, 370 μg/mL (superoxide anion). The ethyl acetate fraction and EO also caused significant inhibition of acetylcholinesterase and butyrylcholinesterase with IC₅₀ values of 70 ± 0.6, 64 ± 0.8 and 75 ± 0.3, 58 ± 0.2, in dose-dependent manner. The first ever gas chromatography–mass spectrometry analysis of the EO obtained from N. nucifera seeds resulted in identification of 19 constituents, mainly comprised of oxygenated sesquiterpenes responsible for their promising bioactivity. The crude and fractions revealed the presence of saponins, flavonoids, steroids, alkaloids, terpenoids and cardiac glycosides in phytochemical investigation.     

Synthesis,EGFR-TK inhibition and anticancer activity of new quinoxaline derivatives

Abstract

Ethyl 4-substituted-3-oxo-quinoxaline-2-carboxylates 3–5 were obtained via alkylation of ethyl 3-oxo-3,4-dihydroquinoxaline-2-carboxylate (1). Compound 1 was heterocyclized using hydrazines, ethylenediamine, and ethanolamine to give pyrazoloquinoxalines 6, 7, diazepinoquinoxaline 8, and oxazepinoquinoxaline 10. The quinoxaline-2-carboxamides 9, 11, 12 were prepared via condensation of compound 1 with different amines. Compound 1 was thiated using Lawesson’s reagent affording quinoxaline-3-thione 13, in fair yield. In addition, the reaction of 4-methyl-3-oxoquinoxaline 3 with some binucleophiles led to a series of new oxoquinoxaline derivatives 14–18. The molecular structure of compounds 1, 3, and 9 was confirmed by X-ray crystallography.

The anti-proliferative activity showed that among all the tested compounds, compounds 3, (IC₅₀ 2.51?±?3.0, 4.22?±?1.6 and 2.27?±?1.9?µM), 11 (IC₅₀ 1.32?±?2.61, 1.41?±?1.23 and 1.18?±?1.91?µM) and 17 (IC₅₀ 1.72?±?1.32, 1.85?±?0.94 and 1.92?±?4.83?µM) showed noteworthy anti-proliferative effects against the three cancer cell lines, HCT116, HePG2 and MCF7, respectively, compared to the reference drugs doxorubicin (IC₅₀ 1.41?±?0.58, 0.90?±?0.62 and 1.01?±?3.02?µM) and erlotinib (IC₅₀ 1.63?±?0.81, 1.57?±?0.62 and 1.49?±?0.54?µM). Compounds 3 (0.899?nM), 11 (0.508?nM) and 17 (0.807) showed strong EGFR inhibitory activity compared to Erlotinib (0.439?nM) and these results are in agreement with the docking study. These results suggest that compounds could probably be promising anticancer agents with EGFR inhibitory activity.     

α-Glucosidase Inhibition and Antioxidant Properties of Streptomyces sp.: In Vitro

Streptomyces strain isolated from the soil sediment was studied for its in vitro α-glucosidase and antioxidant properties. Morphological characterization and 16S rRNA partial gene sequencing were carried out to confirm that the strain Loyola AR1 belongs to genus Streptomyces sp. Modified nutrient glucose broth was used as the basal medium for growth and metabolites production. Ethyl acetate extract of Loyola AR1 (EA-Loyola AR1) showed 50 % α-glucosidase inhibition at the concentration of 860.50?±?2.68 μg/ml. Antioxidant properties such as total phenolic content of EA-Loyola AR1 was 176.83?±?1.17 mg of catechol equivalents/g extracts. EA-Loyola AR1 showed significant scavenging activity on 2,2-diphenyl-picrylhydrazyl (50 % inhibition (IC₅₀), 750.50?±?1.61 μg/ml), hydroxyl (IC₅₀, 690.20?±?2.38 μg/ml), nitric oxide (IC₅₀, 850.50?±?1.77 μg/ml), and superoxide (IC₅₀, 880.08?±?1.80 μg/ml) radicals, as well as reducing power. EA-Loyola AR1 showed strong suppressive effect on lipid peroxidation (IC₅₀, 670.50?±?2.52 μg/ml). Antioxidants of β-carotene linoleate model system reveals significantly lower than butylated hydroxyanisole.     

Chemical composition and in vitro anticancer,antimicrobial and antioxidant activities of essential oil and methanol extract from Rumex nervosus

Chemical composition, antioxidant, anticancer, and antimacrobial activities of essential oil obtained from leaves of Rumex nervosus has been evaluated here for the first time. GC/MS analysis reveals the presence of Palmitoleic Acid (28.35%) and Palmitic acid, (25. 37%) as their methyl ester as major components. The essential oil showed significant DPPH radical scavenging activity (94.907 ± 0.1089% and 94.003 ± 0.0749%) at concentration (100 and 80) μg/mL respectively. The oil showed promising activity against staph aureus, while showed weak activity against (Hela and 3T3) cell lines. The crude extract / fractions of R. nervosus (leaves) showed significant antioxidant activity at dose (100 and 80) μg/mL. Futhermore the crude showed significant activity against (MCF-7 and MDA-MB-231) cell lines with IC₅₀ (20.5138 ± 0.933 and 25.1728 ± 0.9176) μg/mL respectively, and chloroform fraction showed good activity against (MCF-7 and MDA-MB-231) cell lines with IC₅₀ (31.154 ± 0.965 and 42.269 ± 2.1045) μg/mL.     

Chemical composition and in vitro antibacterial and antiproliferative activities of the essential oil from the leaves of Psidium myrtoides O. Berg (Myrtaceae)

In this study, the chemical composition and antibacterial and antiproliferative potential of the essential oil obtained from fresh leaves of Psidium myrtoides (PM-EO) against oral pathogens and human tumour cell lines were investigated for the first time. GC-FID and GC-MS analyses showed that trans-β-caryophyllene (30.9%), α-humulene (15.9%), α-copaene (7.8%), caryophyllene oxide (7.3%) and α-bisabolol (5.3%) are the major constituents of PM-EO. The antibacterial activity of PM-EO against a panel of oral pathogens was investigated in terms of their minimal inhibitory concentrations (MIC) using the broth microdilution method. PM-EO displayed moderate activity against Streptococcus mitis (MIC = 100 μg/mL), S. sanguinis (MIC = 100 μg/mL), S. sobrinus (MIC = 250 μg/mL), and S. salivarius (MIC = 250 μg/mL), and strong activity against S. mutans (MIC = 62.5 μg/mL). The antiproliferative activity in normal (GM07492A, lung fibroblasts) and tumour cell lines (MCF-7, HeLa, and M059 J) was performed using the XTT assay. PM-EO showed 50% inhibition of normal cell growth at 359.8 ± 6.3 μg/mL. Antiproliferative activity was observed against human tumour cell lines, with IC₅₀ values significantly lower than that obtained for the normal cell line, demonstrating IC₅₀ values for MCF-7 cells (254.5 ± 1.6 μg/mL), HeLa cells (324.2 ± 41.4 μg/mL) and M059 J cells (289.3 ± 10.9 μg/mL). Therefore, the cytotoxicity of PM-EO had little influence on the antibacterial effect, since it showed antibacterial activity at lower concentrations. Our results suggest that PM-EO is a promising source of new antibacterial and antitumour agents.     

Trametes versicolor ethanol extract,a promising candidate for health–promoting food supplement

This study aimed to estimate antiradical, antioxidant (AO) and cytotoxic activities of the fungus Trametes versicolor ethanol fruiting body extract. The extract was found to effectively scavenge both O₂^?? and NO^? (29.62 and 52.48 μg/mL, respectively). It also showed a good AO activity in the polarographic HPMC assay (950%/mL). p-Hydroxybenzoic acid may be one of the responsible compounds for the afore-mentioned activities. The same extract also exhibited a concentration-dependent cytotoxicity against MCF-7 and HepG2 tumour cell lines reaching IC₅₀ values of 123.51 and 134.29 μg/mL, respectively with no cytotoxic activity against normal MRC-5 cells. Gentisic, syringic and protocatechuic acids may be among the bioactive principles for the observed cytotoxicity. Taken all together, T. versicolor ethanol extract can be considered as a promising candidate for development of health promoting food supplement.     

Structure activity relationship of bergenin,p-hydroxybenzoyl bergenin, 11-O-galloylbergenin as potent antioxidant and urease inhibitor isolated from Bergenia ligulata

Ethanol extract of the aerial parts of Bergenia ligulata was subjected to solvent–solvent separation followed by various chromatographic techniques that lead to isolation of bergenine (1), p-hydroxybenzoyl bergenin (2), 11-O-galloylbergenin (3) and methyl gallate (4) as major constituents. Ethyl acetate fraction showed a dose-dependent urease inhibitory pattern with IC₅₀ value of 54μg/mL. Structures of compounds 1 and 3 were established by XRD and 2, 4 by NMR. All these compounds were subjected to DPPH scavenging activity, reducing power assay and urease inhibitory activity. The EC₅₀ 7.45 ± 0.2 μg/mL and 5.39 ± 0.28 μg/mL values in terms of antioxidant and reducing power, respectively, were less for 3. Compounds 1–3 showed moderate to significant urease inhibitory potential with IC₅₀ 57.1 ± 0.7, IC₅₀ 48.4 ± 0.3 and 38.6 ± 1.5. Antioxidant activities and urease inhibitory potential were investigated and compound 3 was found to be the most active.