Cytotoxicity profiling of choline chloride-based natural deep eutectic solvents.

This study aims to examine in detail for the first time the cytotoxic profile of twelve choline chloride-based deep eutectic solvents (NADES) against HT-29, Caco-2, MCF-7, and MRC-5 cell lines. All NADES systems were synthesized by microwave synthesis using choline chloride as a hydrogen bond acceptor (HBA) and selected sugars, alcohols, organic acids, and urea as hydrogen bond donors (HBD) with the addition of 20% water (w/w) to all systems. It was observed that the cytotoxic effect predominantly depended on the structure of HBD. Acidic systems, where HBDs were organic acids showed the highest cytotoxic effects in all investigated cell lines. The cytotoxicity depended mostly on the concentration of the NADES system in the cell medium as well as on the chemical constitution of the investigated systems. The highest cytotoxic effects showed acidic systems, especially to the HT-29 cell line. The EC50 value for the citric acid-based system was 3.91 mg mL-1 for the HT-29 cell line which was the most vulnerable to acidic NADES systems.

Phenolic Compounds from Sour Cherry Pomace: Microencapsulation, in Vitro Digestion, and Cell Growth Activities.

The objective of this work was the valorisation of sour cherry (Prunus cerasus L.) pomace as a source of biologically active compounds. To formulate microcapsules, polyphenolic compounds were extracted and encapsulated with maltodextrin as wall material, by freeze-drying. An in vitro digestion study was carried out on obtained encapsulates but also on sour cherry pomace extract and sour cherry pomace freeze-dried powder. The results indicated that encapsulation, as well as freeze-drying, provided a good protective effect on bioactive compounds during digestion. Furthermore, the potential antiproliferative and cytotoxic activities of encapsulates and sour cherry pomace extract were evaluated using breast adenocarcinoma MCF7 cell lines, colon adenocarcinoma HT-29 cell lines, and noncancer cell line. Encapsulates and sour cherry pomace extract showed variable anti-proliferative activity towards all cell lines. Obtained results showed that encapsulation of sour cherry pomace could be useful for improving the stability of polyphenolic compounds in the gastrointestinal tract. The results highlight the bioactive potential of sour cherry pomace as a nutraceutical resource and the protective effects of microencapsulation on the digestion of bioactive compounds.

Novel extraction of polyphenols from sour cherry pomace using natural deep eutectic solvents - Ultrafast microwave-assisted NADES preparation and extraction.

In this work, new approaches for the green extraction of polyphenols from sour cherry pomace were explored. Three Natural Deep Eutectic Solvents (NADES) systems based on choline chloride (ChCl) as a hydrogen bond acceptor (HBA) and malic acid, urea, and fructose (MalA, Ur, and Fru) as hydrogen bond donors (HBD) were used. NADES systems were prepared by heating and stirring (H&S), ultrasound (US), and microwave (MW) methods. It was found that MW-assisted preparation was the fastest requiring less than 30 s. Polyphenol extraction from cherry pomace was performed also by three mentioned methods, and compared with conventional methods. MW extraction was the most rapid with less than 5 min necessary for the extract preparation. All three NADES systems were highly efficient for anthocyanin extraction, but the most efficient was ChCl:MalA system. Extract based on ChCl:MalA system was for 62.33% more efficient for anthocyanin extraction comparing with the conventional solvent.

Medicinal Plants Extracts Impact on Oxidative Stress in Mice Brain Under the Physiological Conditions: the Effects of Corn Silk, Parsley, and Bearberry.

This study was performed to examine the effects of medicinal plant extracts of corn silk (Stigma maydis), parsley leaf (Petroselini folium), and bearberry leaf (Uvae ursi folium) on antioxidant status of the brain of experimental animals (mice) under the physiological conditions. Biological properties of these plants are insufficiently investigated and the aim was to explore their possible antioxidant effects that can alleviate oxidative damage of the brain tissue. Corn silk extract showed positive effect on activities of antioxidant enzymes in mice brain tissue. Parsley extract induced the increase in glutathione content and decrease of lipid peroxidation. Bearberry leaf extract induced catalase activity and decrease of hydroxyl radical content, while malonyldialdehide accumulation was maintained at the control level. Results obtained in this study support the use of corn silk, parsley and bearberry leaves as natural antioxidant sources in the prevention and treatment of brain tissue damages and different diseases caused by oxidative stress.

Coumarin Derivatives Act as Novel Inhibitors of Human Dipeptidyl Peptidase III: Combined In Vitro and In Silico Study.

Dipeptidyl peptidase III (DPP III), a zinc-dependent exopeptidase, is a member of the metalloproteinase family M49 with distribution detected in almost all forms of life. Although the physiological role of human DPP III (hDPP III) is not yet fully elucidated, its involvement in pathophysiological processes such as mammalian pain modulation, blood pressure regulation, and cancer processes, underscores the need to find new hDPP III inhibitors. In this research, five series of structurally different coumarin derivatives were studied to provide a relationship between their inhibitory profile toward hDPP III combining an in vitro assay with an in silico molecular modeling study. The experimental results showed that 26 of the 40 tested compounds exhibited hDPP III inhibitory activity at a concentration of 10 µM. Compound 12 (3-benzoyl-7-hydroxy-2H-chromen-2-one) proved to be the most potent inhibitor with IC50 value of 1.10 µM. QSAR modeling indicates that the presence of larger substituents with double and triple bonds and aromatic hydroxyl groups on coumarin derivatives increases their inhibitory activity. Docking predicts that 12 binds to the region of inter-domain cleft of hDPP III while binding mode analysis obtained by MD simulations revealed the importance of 7-OH group on the coumarin core as well as enzyme residues Ile315, Ser317, Glu329, Phe381, Pro387, and Ile390 for the mechanism of the binding pattern and compound 12 stabilization. The present investigation, for the first time, provides an insight into the inhibitory effect of coumarin derivatives on this human metalloproteinase.

The evaluation of phenolic content, in vitro antioxidant and antibacterial activity of Mentha piperita extracts obtained by natural deep eutectic solvents.

The focus of this study was to evaluate whether six choline chloride-based natural deep eutectic solvents (NADES) could serve as solvents for the extraction of bioactives from the leaves of Mentha piperita. NADES extracted significantly higher amounts of phenols from peppermint than 70% ethanol and may be useful in the extraction of targeted major compounds from peppermint, like rosmarinic acid, at a similar level as 70% ethanol. The microdilution method for in vitro antibacterial activity showed that all NADES exhibit bacterial growth inhibition at a lower concentration than 70% ethanol, especially NADESs containing organic acids. The majority of NADES extracts neutralize DPPH radical at a lower concentration than conventional solvent and showed similar ability to reduce Fe3+ to Fe2+ ions in FRAP assay. NADES can be useful in the isolation of phenolic compounds from plant sources and should be considered as novel, sustainable, and low-cost solvents with a variety of applications.

Exploring fruits from genus Prunus as a source of potential pharmaceutical agents - In vitro and in silico study.

Prunus fruits are recognized to be rich sources of polyphenols with health promoting effect. In this work we evaluated the phenolic profile and bioactivity, namely antioxidant capacity, antiproliferative effect in HT29, and inhibition capacity of α-glucosidase (α-Gls), α-amylase (α-Amy) and human dipeptidyl peptidase III (hDPP III) activities, of traditional Prunus fruits grown in Serbia. Fifteen Prunus samples were investigated and compared: common European plum and three old plum subspecies ('vlaskaca', damson plum and white damson), purple-leaf cherry plum, red and white cherry plum, sweet cherry, sweet cherry-wild type, sour cherry, steppe cherry, mahaleb cherry, blackthorn, peach, and apricot. Principal Component Analysis highlighted steppe cherry and blackthorn as Prunus species with the highest bioactive potential. In silico analysis pointed out rutinoside derivatives of cyanidin and quercetin as the most potent inhibitors of α-Gls, α-Amy and hDPP III enzymes. Quercetin 3-O-rutinoside showed the highest binding energy to α-Gls (-10.6 kcal/mol).

An in vitro and in silico evaluation of bioactive potential of cornelian cherry (Cornus mas L.) extracts rich in polyphenols and iridoids.

In the present research, seven different cornelian cherry (Cornus mas L.) cultivars and selections were examined. In vitro and in silico methods were applied for determining and correlating phytochemical constituents and biological potential. Loganic acid, cornuside, cyanidin3-galactoside, and pelargonidin 3-galactoside were determined as the most dominant compounds, presenting ≥90% of the all detected iridoid and phenolic constituents in the extracts. Cornelian cherry fruits were characterized by high antioxidant capacity and antiproliferative activity on human colon cancer cells (HT29). It was observed the strong inhibitory potential of α-amylase, α-glucosidase, and dipeptidyl peptidase III (DPP III) enzyme activities. Principal component analysis (PCA) was used as a very helpful tool to discriminate the constituents with the highest contribution to tested bioactivities and to highlight the most potent genotypes. PCA, together with binding energies measurements and docking analysis, pointed out pelargonidin 3-robinobioside as the strongest inhibitor of α-glucosidase.

Comparative study of antioxidant status in androgenic embryos of Aesculus hippocastanum and Aesculus flava.

In vivo (leaves and seed embryos) and in vitro (androgenic embryos) antioxidant scavenging activity of Aesculus hippocastanum and Aesculus flava medical plants was examined. Here we report antioxidant enzyme activities of superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase, reduced glutathione quantity, flavonoids, soluble protein contents, quantities of malondialdehyde, and (•)OH radical presence in the investigated plant samples. Total antioxidant capacity of all the samples of A. hippocastanum and A. flava was determined using FRAP, DPPH, and NO(•) radical scavenger capacity. The leaves of A. flava collected from the botanical garden exhibited stronger antioxidant activity (higher activities of SOD, and higher quantities of GSH, TSH, TPC, and scavenging abilities of DPPH and NO(•), and higher FRAP values and lowest quantities of (•)OH and MDA) than in vitro obtained cultures. However, the leaves of A. flava showed higher antioxidant activity than the leaves of A. hippocastanum, and therefore they have a stronger tolerance of oxidative stress. Androgenic embryos of both species had low amount of antioxidants due to controlled in vitro environmental conditions (T, photoperiod, humidity, nutritive factors, and pathogen-free). Our results confirmed that we found optimal in vitro conditions for producing androgenic embryos of both Aesculus species. Also, we assume that horse chestnut androgenic embryos can be used as an alternative source for large-scale aescin production.

Enhancement of antioxidant and isoflavones concentration in gamma irradiated soybean.

Serbian soybean genotype Ana was gamma irradiated at doses of 1, 2, 4, and 10 kGy in order to evaluate the influence of gamma irradiation on isoflavone (genistein, daidzein, and their glycosides genistin and daidzin) contents and hydroxyl radical scavenging effect (HRSE). The increase in genistin and daidzin contents as well as antioxidant activities was observed especially at doses of 4 and 10 kGy. Results were also compared with our previous results relating to total phenol content (TPC), DPPH radical scavenger capacity (DPPH RSC), and ferric reducing antioxidant power (FRAP). Our results indicated that doses up to 10 kGy improve the antioxidant activities of soybean and also nutritional quality with respect to isoflavone content. All results were analyzed by multivariate techniques (correlation matrix calculation and autoscaling transformation of data). Significant positive correlations were observed between genistin, daidzin, DPPH RSC, and HRSE.

Antioxidant characterization of oak extracts combining spectrophotometric assays and chemometrics.

Antioxidant characteristics of leaves, twigs, and acorns from two Serbian oak species Quercus robur L. and Quercus petraea L. from Vojvodina province (northern Serbia) were investigated. 80% ethanol (in water) extracts were used for antiradical power (ARP) determinations against DPPH(•), (•)NO, and O2 (•-) radicals, ferric reducing antioxidant power (FRAP), total phenol, tannin, flavonoid, and proanthocyanidin contents. Permanganate reducing antioxidant capacity (PRAC) was determined using water extracts. Beside, mentioned parameters, soluble proteins, lipid peroxidation (LP), pigments and proline contents were also determined. The data of different procedures were compared and analyzed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA)). PCA found that investigated organs of two different oak tree species possess similar antioxidant characteristics. The superior antioxidant characteristics showed oak leaves over twigs and acorns and seem to be promising source of antioxidants with possible use in industry and pharmacy.

Antioxidant capacity of cornelian cherry (Cornus mas L.) - comparison between permanganate reducing antioxidant capacity and other antioxidant methods.

Ethanol extracts (80% in water) of 10 cornelian cherry (Cornus mas L.) genotypes were studied for antioxidant properties, using methods including DPPH(), ()NO, O(2)(-) and ()OH antiradical powers, FRAP, total phenolic and anthocyanin content (TPC and ACC) and also one relatively new, permanganate method (permanganate reducing antioxidant capacity-PRAC). Lipid peroxidation (LP) was also determined as an indicator of oxidative stress. The data from different procedures were compared and analysed by multivariate techniques (correlation matrix calculation and principal component analysis (PCA)). Significant positive correlations were obtained between TPC, ACC and DPPH(), ()NO, O(2)(-), and ()OH antiradical powers, and also between PRAC and TPC, ACC and FRAP. PCA found two major clusters of cornelian cherry, based on antiradical power, FRAP and PRAC and also on chemical composition. Chemometric evaluation showed close interdependence between PRAC method and FRAP and ACC. There was a huge variation between C. mas genotypes in terms of antioxidant activity.

Antioxidant and scavenging capacity of Anacamptis pyrimidalis L.--pyrimidal orchid from Vojvodina.

In the present study we investigated the antioxidative properties of flowers and aboveground part of Anacamptis pyrimidalis L. from Vojvodina. Activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, and glutathione peroxidase), quantities of malonyldialdehyde, superoxide and hydroxyl radicals and reduced glutathione and also the contents of chlorophylls a and b, carotenoids and soluble proteins were determined. Lipofuscin 'plant age pigments', total antioxidant capacity and scavenging activity were also determined. Our results indicated that the aboveground part of the plant exhibited higher antioxidant activity due to low MDA and lipofuscin pigment accumulation (2.82 nmol/mg protein; 92.90%), higher scavenging activity (54.16%) and antioxidant capacity (432.00 micromol Fe(2+)/dm(3)).

Exploring Equisetum arvense L., Equisetum ramosissimum L. and Equisetum telmateia L. as sources of natural antioxidants.

The antioxidant and scavenging activities of above ground parts of Equisetum arvense L., Equisetum ramosissimum L. and Equisetum telmateia L. phosphate buffer (pH 7) extracts were investigated. Activities of antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidase and glutathione peroxidase), quantities of reduced glutathione, malonyldialdehyde, superoxide and hydroxyl radicals and flavonoid, soluble protein, chlorophyll a, b and carotenoid contents were determined. The total antioxidant capacity was determined by ferric reducing antioxidant power (FRAP) assay. The Equisetum telmateia extract demonstrated scavenging and antioxidant properties better than Equisetum ramosissimum and Equisetum arvense. The ESR signal of DMPO-OH radical adducts in the presence of Equisetum telmateia phosphate buffer (pH 7) extract was reduced by 98.9% indicating that Equisetum telmateia could be a useful source of antioxidants with huge scavenging ability.