Antimutagenic activity of anthocyanins isolated from Aronia melanocarpa fruits

Protective Effect of Polyphenolic Extracts from Hippophae rhamnoides L. and Reynoutria japonica Houtt. on Erythrocyte Membrane

Sea buckthorn and Japanese knotweed are known in many traditional medicine systems to be a great source of bioactive substances. This research aims to compare the bioactivity and protective effects of the phenolic extracts of leaves from sea buckthorn and roots and leaves from the Japanese knotweed on erythrocytes. The polyphenol composition of the extract was analyzed using UPLC-PDA-ESI-MS/MS. The extracts' toxicity and impact on the erythrocytes' osmotic fragility were measured spectrophotometrically. The antioxidant activity was determined based on the inhibition of oxidation of erythrocytes and their membrane induced by 2,2'-Azobis(2-methylpropionamidine) dihydrochloride (AAPH),measured spectrophotometrically and using fluorimetry. To find the possible mechanism of the extracts' action, extract-modified cells were observed under a microscope, and the potential localization of the extract's phytochemical composition was checked using fluorescent probes. The results showed that the used extracts are not toxic to erythrocytes, increase their osmotic resistance, and successfully protect them against free radicals. Extract components localize on the outer part of the membrane, where they can scavenge the free radicals from the environment. Altogether, the presented extracts can greatly protect living organisms against free radicals and can be used to support the treatment of diseases caused by excess free radicals.

Analysis of the Polyphenolic Composition of Vaccinium L. Extracts and Their Protective Effect on Red Blood Cell Membranes

The blueberry fruit of the genus Vaccinium, including high blueberry, low blueberry, and wild bilberry, is consumed for its flavor and medicinal properties. The purpose of the experiments was to investigate the protective effect and mechanism of the interaction of blueberry fruit polyphenol extracts with the erythrocytes and their membranes. The content of polyphenolic compounds in the extracts was determined using the chromatographic UPLC-ESI-MS method. The effects of the extracts on red blood cell shape changes, hemolysis and osmotic resistance were examined. Changes in the order of packing and fluidity of the erythrocyte membrane and the lipid membrane model caused by the extracts were identified using fluorimetric methods. Erythrocyte membrane oxidation was induced by two agents: AAPH compound and UVC radiation. The results show that the tested extracts are a rich source of low molecular weight polyphenols that bind to the polar groups of the erythrocyte membrane, changing the properties of its hydrophilic area. However, they practically do not penetrate the hydrophobic part of the membrane and do not damage its structure. Research results suggest that the components of the extracts can defend the organism against oxidative stress if they are delivered to the organism in the form of dietary supplements.

Modulation of atrazine-induced chromosomal aberrations and cyclin-dependent kinases by aqueous extract of Roylea cinerea (D.Don) Baillon leaves in Allium cepa

Roylea cinerea (D.Don) Baillon an indigenous medicinal plant of Lamiaceae family used for the treatment of several diseases. In the present study, its aqueous (leaves) extract was tested for genoprotective action against atrazine-induced chromosomal aberrations in the root tip cells of Allium cepa. Atrazine is a herbicide of triazine class commonly used to inhibit the growth of broad leaf and grassy weeds. In order to find the concentration of atrazine that exhibits maximum toxicity, its different concentrations (1, 5 and 10 µg/mL) were tested. It was observed that 10 µg/mL concentration was more toxic as it reduced the mitotic index and also increased the chromosomal aberrations. Among all the tested concentrations of aqueous (leaves) extracts (0.25. 0.5, 1.0, 1.5 and 3.0 µg/mL), the3.0 µg/mL concentration in both modes of experiments i.e. pre and post showed a significant reduction in chromosomal aberrations induced by atrazine. To understand the mechanism of protection by plant extract on atrazine-induced chromosomal abnormalities the RT-qPCR studies were conducted to observe the expression of marker genes Cyclin-dependent kinases (CDKs) (CDKA:1, CDKB2:1 and CDKD1:1. For this, the RNA was extracted from root tips treated with extract along with atrazine by TRIzol^®. It was observed that aqueous extract of Roylea cinerea (D.Don) Baillon leaves upregulated the CDKs gene expression in both the modes i.e. pre and post treatments. A critical analysis of results indicated that aqueous extract ameliorated the chromosomal aberrations caused by atrazine which may be be due to the increased expression level of CDKs genes.

Protection of Erythrocytes and Microvascular Endothelial Cells against Oxidative Damage by Fragaria vesca L. and Rubus idaeus L. Leaves Extracts-The Mechanism of Action

The aim of this work is to determine the biological activity of ellagitannins rich extracts from leaves of raspberry (Rubus idaeus L.) and wild strawberry (Fragaria vesca L.) in relation to cells and cell membranes. Detailed qualitative and quantitative analysis of phenolic compounds of the extract was made using chromatographic methods. Cytotoxic and antioxidant activities of tested extracts in relation to erythrocytes and human vascular endothelial cells (HMEC-1) were determined by using fluorimetric and spectrophotometric methods. In order to establish the influence of the extracts on the physical properties of the membrane, such as osmotic resistance and erythrocytes shapes, mobility and/or hydration of polar heads and fluidity of hydrocarbon chains of membrane lipids, microscopic and spectroscopic methods were used. The results showed that the extracts are non-toxic for erythrocytes and HMEC-1 cells (up to concentration of 50 µg/mL), but they effectively protect cells and their membranes against oxidative damage. The increase in osmotic resistance of erythrocytes, formation of echinocytes and changes only in the polar part of the membrane caused by the extracts demonstrate their location mainly in the hydrophilic part of the membrane. The results indicate that tested extracts have high biological activities and may be potentially used in delaying the ageing process of organisms and prevention of many diseases, especially those associated with oxidative stress.

Extraction of Antioxidants from Aronia mitschurinii Juice Using Macroporous Resins

Antioxidants play a vital role in the human body by defending cells from damage caused by free radicals, highly reactive products of oxidation reactions. A major source of antioxidants is fruits and vegetables. Aronia mitschurinii, a breed created at the end of the 19th century by crossbreeding wild Aronia melanocarpa and Russian Mountain Ash, produces fruits with one of the highest known content of hydrophilic antioxidants. Aronia fruit contains a potent blend of anthocyanins, polyphenols, and flavonoids. The most popular way of consuming the fruit is through juicing. Yet, due to very high concentrations of tannins in the juice, very few food-related applications have been developed. Resin extraction of antioxidants provides an alternative for utilizing valuable phytochemicals from crops for applications in the food industry as nutraceutical supplements and more. To increase the market value of the plant, it is important to determine what resins can extract the optimum concentration of antioxidants from aronia juice, pulp, and whole berries. We have shown that macroporous resins such as Amberlite XAD 1180N, Amberlite XAD 7HP, Amberlite XAD 761, and Amberlite FPX66, which have been reported to be effective in extracting the anthocyanins and polyphenols from other fruit juices, skins of red grapes, and the wild breed, are also effective for use in juice, pulp, and whole fruits of Aronia mitchurinii. However, the extremely high content of antioxidants presents a challenge to obtaining high recovery; a notable change in the juice/resin ratio is required to obtain a higher recovery value. Our results showed that Amberlite FPX66 was the best at extracting anthocyanins, polyphenols, and flavonoids from aronia juice. A separate experiment conducted to determine how to optimize the efficiency of FPX66 extraction revealed that increasing the resin/juice ratio increased the percent recovery of anthocyanins from aronia juice. Moreover, we have compared recovery between juice, pulp, and whole aronia berries and batch versus column extraction.

Comparison of Osmotic Resistance, Shape and Transmembrane Potential of Erythrocytes Collected from Healthy and Fed with High Fat-Carbohydrates Diet (HF-CD) Pigs-Protective Effect of Cistus incanus L. Extracts

Long-term high fat-carbohydrates diet (HF-CD) contributes to the formation of irreversible changes in the organism that lead to the emergence of civilization diseases. In this study, the impact of three-month high-fat diet on the physical properties of erythrocytes (RBCs) was studied. Furthermore, the biological activity of Cistus incanus L. extracts, plant known with high pro-health potential, in relation to normal and HF-CD RBCs, was determined. Obtained results have shown that, applied HF-CD modified shape, membrane potential and osmotic resistance of erythrocytes causing changes in membrane lipid composition and the distribution of lipids. The impact of HF-CD on physical properties of RBCs along with atherosclerotic lesions of the artery was visible, despite the lack of statistically significant changes in blood morphology and plasma lipid profile. This suggests that erythrocytes may be good markers of obesity-related diseases. The studies of biological activity of Cistus incanus L. extracts have demonstrated that they may ameliorate the effect of HF-CD on erythrocytes through the membrane-modifying and antioxidant activity.

The Effect of Filtration on Physical and Chemical Properties of Osmo-Dehydrated Material

Osmotic dehydration (OD) performed in concentrated fruit juices used as osmotic solution (OS) comes with some limitations resulting from the material cell structure and is not entirely recognized at the moment. Filtration of the juice could provide some insight into the phenomena occurring throughout the OD. Therefore, the main aim of the study was to recognize the mechanism of selective penetration during OD and evaluate the effect of filtration on physical and chemical properties of osmo-dehydrated material. For this purpose, OD of pumpkin in non-filtrated and filtrated (filters 0.2, 0.45, 0.8, 1.2, 3, 5 and 8 μm) concentrated chokeberry juice was carried out in the study. Moreover, scanning electron microscope (SEM) images were provided. Total phenolic content (TPC) and antioxidant capacity measured by Ferric Reducing Antioxidant Potential (FRAP) and Trolox Equivalent Antioxidant Capacity (TEAC ABTS) of OS and the material were determined. It was found that even though filtration of osmotic solution had a moderate influence on the mass transfer, it greatly affected the chemical composition of dehydrated material. The best option, considering both chemical and physical properties of the dehydrated material, is the use of non-filtrated solution. However, when shorter time of OD is considered, much better results are obtained for filtrated solutions.

Influence of supercritical fluid extraction parameters in preparation of black chokeberry extracts on total phenolic content and cellular viability

Black chokeberries (Aronia melanocarpa), deciduous shrubs of the Rosaceae family, are native to northeastern North America. Chokeberry fruits are cultivated to make jellies, juices, and wines. Black chokeberry pulp is rich in phenolics and other antioxidants and exhibits potential for health and food packaging benefits. Chokeberries' in vitro antioxidant activity is among the highest values of all berries, though chokeberry extraction techniques frequently employ environmentally unfavorable solvents or are time-inefficient. Batch extraction of antioxidants from chokeberry pomace using supercritical carbon dioxide with an ethanol modifier was used to examine the effects of plant loading, pressure, temperature, and percent ethanol by weight. Effects on total phenolic content (TPC) and the optimal conditions for extractions within these ranges are reported. Multivariate analyses reveal the following relationships of extraction conditions upon TPC: Temperature is directly proportional, percent ethanol by weight is inversely proportional, and chokeberry loads can be increased to enhance antioxidant activity, though not through a linear relationship. In studies involving 0.5 g plant load, the conditions 24.9MPa, 68°C, 90wt-% CO2, and 10wt-% ethanol generated the highest TPC value, 3.42 ± 0.20 mg gallic acid equivalents/gram chokeberry. Chokeberry extracts displayed antiproliferative effects on the SKBr3 breast cancer line and the 52KO MEF line, although TPC was not predictive of cellular responses. HPLC-MS data suggest cyanidin hexose and cyanidin pentose compounds as well as quercetin deoxyhexose-hexose as components of the more favorable extraction product that reflected a significant decrease in viability for the extract in comparison with ethanol control in the SKBr3 breast cancer line.

Comparative analysis of antioxidant activity and phenolic compounds in the fruits of Aronia spp

Chokeberry (Aronia Medik.) is a non-traditional fruit plant known as a rich source of biologically active compounds and inhibits the numerous biological activities. We compared the antioxidant activity and phenolic compounds of fruits between widely cultivated Aronia mitschurinii (AM-TCH, from Tchekhov district; AM-D, from Dmitrov district; AM-OZ, from Orekhovo-Zuevsky district of Moscow region, Russia) and introduced North American Aronia species (Aronia arbutifolia (AA-M), A. melanocarpa (AML-M), A. × prunifolia (AP-M), which have not been planted yet in the arboretum of Main Botanical Garden of the Russian Academy of Sciences (Moscow). Studying samples were collected in their secondary distribution range. Ethanolic extracts were determined for antioxidant capacity (antioxidant activity by DPPH and phosphomolybdenum methods, the total content of polyphenols, flavonoids, phenolic acids) and measured spectrophotometrically. As standards were used Trolox (TE) for antioxidant activities, gallic acid (GAE) for polyphenol content, quercetin (QE) for flavonoid content, caffeic acid (CAE) for phenolic acid content. The antioxidant activity by DPPH method in ethanol extracts of investigated plants was from 6.96 (AM-D) to 8.89 (AM-OZ) mg TE.g-1 DW. Reducing the power of investigated extracts exhibited activity from 151.47 (AM-OZ) to 297.8 (AA-M) mg TE.g-1 DW. The content of polyphenol compounds determined from 25.98 (AM-TCH) to 54.39 (AA-M) mg GAE.g-1 DW, phenolic acids content was from 7.76 (AP-M) to 11.87 (AM-D) mg CAE.g-1 DW and the content of flavonoids detected from 8.12 (AM-OZ) to 16.62 (AM-D) mg QE.-1 DW. Obtained data showed a strong correlation between the content of polyphenol compounds and reducing the power of extracts (r = 0.700), between flavonoids and phenolic acids (r = 0.771) and also between phenolic acids and reducing power (r = 0.753) in Aronia ethanol extracts. Fruits of investigated species of Aronia can be propagated as a source of polyphenol compounds with antioxidant activity and obtained results may use for farther pharmacological study.

Anthocyanin-rich haskap (Lonicera caerulea L.) berry extracts reduce nitrosamine-induced DNA damage in human normal lung epithelial cells in vitro

Diets rich in polyphenols are known to reduce cancer among high-risk populations. Haskap (Lonicera caerulea L.) berry has abundant phenolic acids and flavonoids, especially anthocyanins. Tobacco-specific nitrosamine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) present in cigarette smoke, is a major lung carcinogenic factor. We analyzed the efficacy of anthocyanin-rich haskap berry extracts in preventing DNA damage induced by 4-[(acetoxymethyl) nitrosamino]-1-(3-pyridyl)-1-butanone (NNKOAc), a precursor of NKK, in human lung epithelial BEAS-2B cells in vitro. A cocktail of monomeric polyphenols from haskap berries was extracted separately in ethanol and water and profiled. Sub-lethal concentrations of NNKOAc were used to induce DNA damage in BEAS-2B cells, and a cell viability assay was performed to confirm that the tested concentrations of haskap extracts were not cytotoxic to BEAS-2B cells. Cells were pre-treated with the haskap extracts prior to NNKOAc exposure. Dose-dependent DNA damage was observed with carcinogenic NNKOAc, but did not occur in the presence of the haskap extracts. Pre-treatment of the cells with the haskap extracts significantly reduced NNKOAc-induced DNA damage, DNA fragmentation, and intracellular reactive oxygen species and upregulated the ATM-dependent DNA damage repair cascade compared to non-treated BEAS-2B cells. The protective effect of haskap extracts could be related to their polyphenol content and high antioxidant capacity.

Anti-inflammatory effect from extracts of Red Chinese cabbage and Aronia in LPS-stimulated RAW 264.7 cells

A chronic inflammatory environment facilitates tumor growth and proliferation. Fruits and vegetables are important sources of anthocyanins, polyphenols, and other biologically active substances that can favorably affect the pathogenesis of cancer. The objective of the study was to investigate the anti-inflammatory effects of Red Chinese cabbage (RC) and mixture of commercial Red Chinese cabbage leaves and Aronia fruits (ARC) in LPS-stimulated RAW 264.7 cells. The RAW 264.7 cells were cultured and measured the cytotoxicity by using an MTT assay. The inflammatory markers, such as nitrite, IL-6, and TNF-alpha expression, were evaluated using ELISA, and protein expression of inflammatory markers like iNOS and COX-2 was analyzed using Western blot. MTT assays showed that pretreatment of RAW 264.7 cells with RC and ARC did not change cell growth or cytotoxicity. We also found that ARC extracts reduced inflammation-related biomarker (TNF-a, IL-6, and NO) production and gene expression (iNOS, COX-2). Our results suggested that ARC has good anti-inflammatory properties compared with RC that maybe used as potential nutrients for treating inflammatory diseases.

Chemical and bioactivity screening of subcritical water extracts of chokeberry (Aronia melanocarpa) stems

Subcritical water extracts of chokeberry (Aronia melanocarpa) stems were chemically and biologically characterised. Chemical profile was defined by GC-MS analysis whereas anti-oxidant, anti-diabetic and tyrosinase-inhibitory activities of the extracts were investigated by in vitro assays. Antioxidant activity assays revealed strong activity against DPPH radical (IC₅₀ = 0.1 mg/mL) and reducing power (IC₅₀ = 0.25 mg/mL). The extracts demonstrated remarkable amylase (0.59 mmol ACAE/g) and glucosidase (7.50 mmol ACAE/g) inhibitory effects. Anti-tyrosinase activity of aronia stem extracts obtained by subcritical water was calculated to be 15.87 mg KAE/g extract. GC-MS analysis of chokeberry stem subcritical water extracts revealed the presence of different chemical classes. The compounds present in the highest concentrations were polyols arabitol (13.7%), xylitol (3.5%), and glycerol (1.96%), as well as sugars such as fructose (3.04%), ribose (1.99%) and xylulose (1.18%).

Additive effect of walnut and chokeberry on regulation of antioxidant enzyme gene expression and attenuation of lipid peroxidation in d-galactose-induced aging-mouse model

Studies have highlighted the association between the cellular damage caused by reactive oxygen species and aging. The reducing sugar d-galactose causes aging-related changes and oxidative stress. Lipids are the first target of free radicals, and lipid peroxidation is related to aging. Walnut (Juglans regia Chandler) kernel contains antioxidant phenolic compounds, and chokeberry (Aronia melanocarpa) is one of the richest sources of polyphenols, including anthocyanins, among other fruits. Polyphenols from chokeberry exhibit antioxidant and anti-inflammatory activities. In this study, the additive antioxidative effect of walnut and chokeberry mixture was evaluated by oxidative stress index in d-galactose-induced aging model. Thirty-five Balb/c mice (8 weeks old) were divided into following five groups (n = 7 in each group): normal control (C), d-galactose control (D), d-galactose with chokeberry diet (CH), d-galactose with walnut diet (W), and d-galactose with walnut and chokeberry mixture diet (WCH). In all treatment diets groups, the levels of serum, hepatic, and kidney malonaldehyde were significantly lower than D group and the levels were approaching to control level. Moreover, the kidney malondialdehyde levels were significantly lower in WCH group compared with the control group. This study also confirmed the activities of antioxidant enzymes in liver, as the levels of superoxide dismutase, and glutathione peroxidase were significantly increased in CH group compared to in W or CH groups. The results of this study supported the additive effect of walnut and chokeberry on increment of antioxidant enzyme gene expression in liver and consequently the attenuation of lipid peroxidation in serum, liver, and kidney in d-galactose-induced aging-mouse model. Further studies are needed to investigate the detailed mechanism underlying the additive antioxidative effects in various tissues.

Morphological characteristics for fruits of aronia mitschurinii A.K. Skvortsov & Maitul

The aim of this study was to determine morphometric characteristics of fruits within some phenotypes of Aronia mitschurinii A.K. Skvortsov & Maitul. Their morphometric parameters were following: weight from 0.75 g (AM-03) to 1.52 g (AM-04), length from 9.46 mm (AM-03) to 12.73 mm (AM-04), diameter from 10.49 mm (AM-03) to 13.73 mm (AM-04), fruits number in the corymb from 11.33 (AM-07) to 20.13 (AM-03), cumulative weight of fruits in the corymb from 10.42 g (AM-07) to 21.73 g (AM-04), volume of fruits from 0.55 (AM-03) to 1.26 (AM-04) cm3. The shape index of the fruits was found in the range of 0.87 (AR-01, AR-05, AR-07) to 0.93 (AM-02). The analysis of coefficient of variation showed the difference of variability in morphological characteristics between Aronia mitschurinii samples. Data showed that the most variability of important selection characteristics are the average cumulative mass of fruits in a сorymb - from 12.34 (AM-03) to 38.61 (AM-02) % and fruit number of fruits in the сorymb - from 14.56 (AM-03) to 36.88 (AM-02) %. The other characteristics are more or less stable. The introduction population of the Aronia mitschurinii, was created in the M.M. Gryshko National Botanical Garden in Kyiv, has a sufficient potential for successful selection work.

Fruits of Black Chokeberry Aronia melanocarpa in the Prevention of Chronic Diseases

In recent years, growing attention has been focused on the utilization of natural sources of antioxidants in the prevention of chronic diseases. Black chokeberry (Aronia melanocarpa) represents a lesser known fruit species utilized mainly as juices, purees, jams, jellies and wine, as important food colorants or nutritional supplements. The fruit is valued as a great source of antioxidants, especially polyphenols, such as phenolic acids (neochlorogenic and chlorogenic acids) and flavonoids (anthocyanins, proanthocyanidins, flavanols and flavonols), particularly cyanidin-3-galactoside and cyanidin-3-arabinoside, as well as (-)-epicatechin units. The berries of A. melanocarpa, due to the presence and the high content of these bioactive components, exhibit a wide range of positive effects, such as strong antioxidant activity and potential medicinal and therapeutic benefits (gastroprotective, hepatoprotective, antiproliferative or anti-inflammatory activities). They could be also contributory toward the prevention of chronic diseases including metabolic disorders, diabetes and cardiovascular diseases, because of supportive impacts on lipid profiles, fasting plasma glucose and blood pressure levels.

Effects of Different Growing Regions on Quality Characteristics, Bioactive Compound Contents, and Antioxidant Activity of Aronia (Aronia melanocarpa) in Korea

The objective of this study was to determine the effects of different growing regions on quality characteristics, total bioactive compound contents, and in vitro antioxidant activity in aronia. Aronia grown in 3 different regions (Sangjoo, Ulju, and Youngcheon) in Korea was obtained and used fresh or as a freeze-dried powder. No statistically significant differences were observed for moisture, ash, crude lipid, and crude protein contents in aronia sampled from the 3 different regions. Aronia grown in Sangjoo had the highest total acid content and the lowest sugar content and pH value. Conversely, aronia grown in Youngcheon possessed the lowest total acid content and the highest sugar content and pH value. Aronia grown in Sangjoo possessed relatively high levels of polyphenols, flavonoids, and anthocyanins, as well as high antioxidant activity in comparison with aronia produced in other regions. Aronia grown in Youngcheon scored the highest for taste and overall acceptability in sensory evaluations, which may be related to the high sugar content and pH, and the low total acidity of the fruits. It is possible that higher sugar contents and pH, and lower total acidity in the aronia grown in Youngcheon result in more preferable sensory characteristics. However, they also contain relatively low levels of total polyphenols, flavonoids, and anthocyanins, and have low antioxidant activity as measured by 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assays.

Physical Effects of Buckwheat Extract on Biological Membrane In Vitro and Its Protective Properties

Buckwheat is a valuable source of many biologically active compounds and nutrients. It has properties that reduce blood cholesterol levels, and so reduces the risk of atherosclerosis, seals the capillaries, and lowers blood pressure. The aim of the study was to determine quantitative and qualitative characteristics of polyphenols contained in extracts from buckwheat husks and stalks, the biological activity of the extracts, and biophysical effects of their interaction with the erythrocyte membrane, treated as a model of the cell. An analysis of the extract’s composition has shown that buckwheat husk and stalk extracts are a rich source of polyphenolic compounds, the stalk extracts showing more compounds than the husk extract. The study allowed to determine the location which incorporated polyphenols occupy in the erythrocyte membrane and changes in the membrane properties caused by them. It was found that the extracts do not induce hemolysis of red blood cells, causing an increase in osmotic resistance of erythrocytes. They affect mainly the hydrophilic region by changing the degree of order of the polar heads of lipids, but do little to change the fluidity of the membrane and its hydration. The results showed also that polyphenolic substances included in the extracts well protect the membranes of red blood cells against oxidation and exhibit anti-inflammatory effect.

Chokeberry attenuates the expression of genes related to de novo lipogenesis in the hepatocytes of mice with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), which is characterized by steatosis, is a major public health concern. Previous studies have shown that chokeberry has anti-inflammatory, antimutagenic, hepatoprotective, cardioprotective, and antidiabetic effects. In this study, we hypothesized that chokeberry powder can attenuate the expression of genes related to de novo lipogenesis and the triglyceride levels in the hepatocytes of mice with high-fat diet-induced NAFLD. After coadministering chokeberry powder for 8weeks (0.5% and 1% powder) with a high-fat diet, mice that consumed chokeberry powder diets, regardless of the dose, had significantly lower liver triglyceride levels than control mice that were fed a high-fat diet (P=.0145 and P<.0012, respectively). Compared with mice that were fed a high-fat diet, mice that were given 1% chokeberry powder exhibited significantly decreased mRNA expression of sterol regulatory element-binding protein (P=.009) and acetyl-CoA carboxylase (P=.0032) in the liver. Compared with mice in the control group, fatty acid synthase (FAS) expression significantly increased in the mice that were fed a high-fat diet, but both chokeberry powder-treated groups had significantly decreased FAS expression (P=.0157 and P<.0001, respectively). The size of the fat droplets was decreased in the livers of the chokeberry-supplemented groups. In summary, the administration of chokeberry powder may help attenuate high-fat diet-induced NAFLD by regulating the expression levels of sterol regulatory element-binding protein, acetyl-CoA carboxylase, and FAS and by decreasing the size of the fat droplets in the liver.

Modification of the properties of biological membrane and its protection against oxidation by Actinidia arguta leaf extract

The aim of the study was to determine the polyphenol composition and biological activity of an extract from the leaves of kiwi. Antioxidant and hemolytic activity of the extract were examined, as well as its effect on the physical properties of the erythrocyte membrane such as osmotic resistance, membrane fluidity, and packing order of its hydrophilic area. Antioxidant activity of the extract was determined in relation to the erythrocyte membrane oxidized with free radicals induced by UVB and UVC radiation and the compound AAPH. Chromatographic, spectrophotometric and fluorimetric methods were applied in the research. The obtained results showed that kiwi leaves are a rich source of polyphenolic substances, mainly catechins and their dimers, which do not induce red blood cell hemolysis but make them stronger and more resistant to changes in medium tonicity. Substances contained in the extract effectively protect erythrocyte membranes against oxidation induced by physicochemical factors, the effectiveness of the protection depending on the concentration and type of free radical inducer. In addition, the study showed that the kiwi extract increases fluidity of the erythrocyte membrane and causes an increase in packing disorder in the hydrophilic membrane area. The changes seem to be due to the presence of polyphenolic substances in the extract, mainly in the region of the polar heads of lipids, where they can form a barrier protecting the membrane against diffusion of free radicals to the membrane interior. The effects of the extract evidenced by the present research, in particular protection of the biological membrane against free radicals induced by physicochemical agents, make it a potential valuable food additive, to enrich it with polyphenolic compounds that inhibit lipid oxidation in food exposed to UVB radiation. Supplementing the organism with substances contained in kiwi leaves is expected to provide protection against many diseases that develop as a result of oxidative stress.

Microplate quantification of total phenolic content from plant extracts obtained by conventional and ultrasound methods

INTRODUCTION

There is increasing interest in phenolic compounds around the world because of their potential positive impact on human health. Phenolic compounds are largely found in fruits and vegetables. Extraction of phenolic compounds is a very important step in their recovery. The newly developed technique of ultrasound-assisted extraction (UAE) appears to be an advantageous alternative compared with conventional techniques, because it is simple and environmental friendly. The potential of UAE needs to be evaluated in each plant in order to demonstrate its efficiency.

OBJECTIVE

The objective of the present study was to compare a conventional method and UAE on the extraction efficiency of phenolic compounds from Jatropha dioica, Fluorensia cernua, Turnera diffusa and Eucalyptus camaldulensis plants and evaluate the in vitro anti-oxidant potential.

METHODS

Validation of the new method was carried out using mixed-model methodology and regression analysis. Feasibility of this new method was shown and applied using several plants extracts obtained by different extraction methods from semi-arid Mexican plants, which were characterised by high levels of polyphenols. Additionally, the anti-oxidant potential of these extracts was determined by 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity.

RESULTS

Results showed that the new microplate method can be used to determine total phenolic content in plant extracts. Additionally, an alternative extraction method by ultrasound was less efficient compared with the conventional method.

CONCLUSION

The tested plants are good candidates to obtain nutraceuticals and functional food ingredients.

Three-dimensional quantitative structure-activity relationship and docking studies in a series of anthocyanin derivatives as cytochrome P450 3A4 inhibitors

The cytochrome P450 (CYP)3A4 enzyme affects the metabolism of most drug-like substances, and its inhibition may influence drug safety. Modulation of CYP3A4 by flavonoids, such as anthocyanins, has been shown to inhibit the mutagenic activity of mammalian cells. Considering the previous investigations addressing CYP3A4 inhibition by these substances, we studied the three-dimensional quantitative structure–activity relationship (3D-QSAR) in a series of anthocyanin derivatives as CYP3A4 inhibitors. For the training dataset (n=12), comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) yielded crossvalidated and non-crossvalidated models with a q² of 0.795 (0.687) and r² of 0.962 (0.948), respectively. The models were also validated by an external test set of four compounds with r² of 0.821 (CoMFA) and r² of 0.812 (CoMSIA). The binding affinity modes associated with experimentally derived IC₅₀ (half maximal inhibitory concentration) values were confirmed by molecular docking into the CYP3A4 active site with r² of 0.66. The results obtained from this study are useful for a better understanding of the effects of anthocyanin derivatives on inhibition of carcinogen activation and cellular DNA damage.

Intake of anthocyanidins pelargonidin and cyanidin reduces genotoxic stress in mice induced by diepoxybutane, urethane and endogenous nitrosation

Pelargonidin (PEL) and cyanidin (CYN) are among the six most abundant anthocyanidins which provide red, blue and purple colors to fruits and vegetables. Health benefits associated with intake of anthocyanins have been attributed mainly to antioxidant activity of these color pigments. The aim of our present study was to assess in mice the impact of PEL and CYN intake on genotoxic stress induced by DNA damaging environmental toxicants. These anthocyanidins were administered by gavage to mice before exposure to genotoxic carcinogens diepoxybutane (DEB) and urethane (URE). In addition, the inhibitory effect of PEL and CYN on endogenous nitrosation was evaluated by using a model nitrosation reaction mixture consisting of methyl urea (MU)+sodium nitrite (SN) which reacts in the stomach to form the carcinogenic methyl nitrosourea (MNU). All the test doses of PEL (2.5-20 mg/kg) and CYN (1-4 mg/kg) significantly reduced the genotoxicity of DEB. A dose-related increase was observed for antigenotoxicity of PEL against URE. The lowest test-dose of CYN showed maximum protection against URE. Co-administration of PEL/CYN with the nitrosation reaction mixture led to reduction in genotoxicity. CYN was more effective as an inhibitor of endogenous nitrosation. Combination of PEL with ascorbic acid (AA) enhanced the antinitrosating effect when compared to that with each phytochemical alone. The results of our present study indicate that common anthocyanidins PEL and CYN can play a major role in reducing genotoxic stress induced by environmental toxicants.

Activity of hawthorn leaf and bark extracts in relation to biological membrane

The aim of the study was to identify and determine the percent content of polyphenols in extracts from leaves and hawthorn bark, to examine the effect of the extracts on the properties of the biological membrane as well as to determine their antioxidant activity toward membrane lipids. In particular, a biophysical investigation was conducted on the effect of hawthorn extracts on the osmotic resistance and morphology of erythrocyte cells and on the packing of the heads of membrane lipids. Analysis of the polyphenol content of extracts used the HPLC method. Analysis of the polyphenol composition has shown a dominant share of procyanidins and epicatechin in both extracts. The research showed that the polyphenolic compounds contained in hawthorn extracts are incorporated mainly into the hydrophilic part of the erythrocyte membrane, inducing echinocyte shapes. They also diminish the packing order of the lipid polar heads of the membrane, as evidenced by the lowered generalized polarization values of Laurdan. The substances used induced increased osmotic pressure of erythrocytes, making them less sensitive to changes in osmotic pressure. The presence of the extract compounds in the outer hydrophilic part of the erythrocyte membrane, evidenced by examination of the shapes and packing in the hydrophilic part of membrane, indicates that the substances constitute a kind of barrier that protects the erythrocyte membrane against free radicals, while the membrane-bound extracts do not disturb the membrane structure and, thus, do not cause any side effects.

Phytochemical profile of a blend of black chokeberry and lemon juice with cholinesterase inhibitory effect and antioxidant potential

In this study, black chokeberry concentrate was added (5% w/v) to lemon juice, since previous reports suggested potential health benefits of this blend. The phytochemical composition, antioxidant capacity (scavenging of DPPH, superoxide and hydroxyl radicals, and hypochlorous acid), and inhibitory activity against cholinesterase of the new blend were determined and compared with those of lemon juice and chokeberry in citric acid (5%). The chokeberry concentrate, rich in cyanidin-glycosides, quercetin derivatives, and 3-O-caffeoylquinic acid, and lemon juice, possessing flavones, flavanones, quercetin derivates, and hydroxycinnamic acids, were characterised. The new drink showed a higher antioxidant effect than the chokeberry or lemon controls for all the tested methods, except for hypochlorous acid, in which lemon juice displayed higher activity. Both the lemon juice and chokeberry controls inhibited acetylcholinesterase and butyrylcholinesterase, and this effect was increased in the new mixtures. The results of the different radical scavenging assays indicate that the lemon-black chokeberry (5% w/v) mixture was more antioxidative than the respective controls separately. Moreover, their inhibition of cholinesterase is of interest regarding neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, or senile dementia.

Interaction of selected anthocyanins with erythrocytes and liposome membranes

Anthocyanins are one of the main flavonoid groups. They are responsible for, e.g., the color of plants and have antioxidant features and a wide spectrum of medical activity. The subject of the study was the following compounds that belong to the anthocyanins and which can be found, e.g., in strawberries and chokeberries: callistephin chloride (pelargonidin-3-O-glucoside chloride) and ideain chloride (cyanidin-3-O-galactoside chloride). The aim of the study was to determine the compounds’ antioxidant activity towards the erythrocyte membrane and changes incurred by the tested anthocyanins in the lipid phase of the erythrocyte membrane, in liposomes composed of erythrocyte lipids and in DPPC, DPPC/cholesterol and egg lecithin liposomes. In particular, we studied the effect of the two selected anthocyanins on red blood cell morphology, on packing order in the lipid hydrophilic phase, on fluidity of the hydrophobic phase, as well as on the temperature of phase transition in DPPC and DPPC/cholesterol liposomes. Fluorimetry with the Laurdan and Prodan probes indicated increased packing density in the hydrophilic phase of the membrane in the presence of anthocyanins. Using the fluorescence probes DPH and TMA-DPH, no effect was noted inside the hydrophobic phase of the membrane, as the lipid bilayer fluidity was not modified. The compounds slightly lowered the phase transition temperature of phosphatidylcholine liposomes. The study has shown that both anthocyanins are incorporated into the outer region of the erythrocyte membrane, affecting its shape and lipid packing order, which is reflected in the increasing number of echinocytes. The investigation proved that the compounds penetrate only the outer part of the external lipid layer of liposomes composed of erythrocyte lipids, DPPC, DPPC/cholesterol and egg lecithin lipids, changing its packing order. Fluorimetry studies with DPH-PA proved that the tested anthocyanins are very effective antioxidants. The antioxidant activity of the compounds was comparable with the activity of Trolox®.

Interaction between plant polyphenols and the erythrocyte membrane

The purpose of these studies was to determine the effect of polyphenols contained in extracts from apple, strawberry and blackcurrant on the properties of the erythrocyte membrane, treated as a model of the biological membrane. To this end, the effect of the substances used on hemolysis, osmotic resistance and shape of erythrocytes, and on packing order in the hydrophilic region of the erythrocyte membrane was studied. The investigation was performed with spectrophotometric and fluorimetric methods, and using the optical microscope. The hemolytic studies have shown that the extracts do not induce hemolysis at the concentrations used. The results obtained from the spectrophotometric measurements of osmotic resistance of erythrocytes showed that the polyphenols contained in the extracts cause an increase in the resistance, rendering them less prone to hemolysis in hypotonic solutions of sodium chloride. The fluorimetric studies indicate that the used substances cause a decrease of packing order in the hydrophilic area of membrane lipids. The observations of erythrocyte shapes in a biological optical microscope have shown that, as a result of the substances' action, the erythrocytes become mostly echinocytes, which means that the polyphenols of the extracts localize in the outer lipid monolayer of the erythrocyte membrane. The results obtained indicate that, in the concentration range used, the plant extracts are incorporated into the hydrophilic area of the membrane, modifying its properties.