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Antioxidant activity of potato juice

Antioxidant activity of potato juice

The observed differences in values of the antioxi- dative potential determined using different methods should be attributed to the limitations of each of these methods. The Folin-Ciocalteu method was developed to determine the content of polyphenolic compounds utilising the colour reaction taking place between polyphenols contained in a given sample and the F-C reagent. However, this reagent also reacts with other organic substances such as: organic acids, sugars, aro- matic and inorganic amines, e.g. ammonium sulphate, sodium phosphate [Zhang et al. 2006, Yu and Dahl- gren 2000]. Also the method which utilises the ABTS reagent, although in theory should make it possible to establish the total antioxidative activity, in practice is not free of making interpretational errors. The limita- tion of this method is the fact that the ABTS reagent, in combination with fl avonoids, develops strong an- tioxidative complexes leading to the determination of overestimated values of the antioxidative potential [Arts et al. 2004].
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Phenolic compounds in native potato (Solanum tuberosum L.) cooking water, with potential antioxidant activity

Phenolic compounds in native potato (Solanum tuberosum L.) cooking water, with potential antioxidant activity

(46.18), vanillin (16.03), p-coumaric acid (9.73), caffeic acid (9.41), 4-hydroxy -3-methoxy cinnamaldehyde (7.83), ferulic acid (5.97), neochlorogenic acid (2.07). On RP water, the main phenolic compound mg/100 g of raw potato) is coumarin (9.31). The explanation for this higher concentration of metabolites in SP- potato cooking water could beI: a) During boiling of potatoes in water, the contact surface between potatoes and water is higher, therefore is a great transfer of analytes to water increasing the concentration of phenolic compounds in water; b) The phenolic compounds are leached into the hot water and are often increased by the effect of the heat that extracts them and improves their bioavailability. They are highly reactive species that participate in the reactions that occur during the cooking process and are related to the cultivarI: agro-technical processes, climatic conditions, maturity during the harvest, post-harvest manipulations (Stratil et al., 2006; Palermo et al., 2014).
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Effect of high hydrostatic pressure on ascorbic acid, phenolic compounds and antioxidant activity of pera rio orange juice

Effect of high hydrostatic pressure on ascorbic acid, phenolic compounds and antioxidant activity of pera rio orange juice

For the HHP treatment, orange juice (100 mL) was packaged in heat sealed PE bags (Selovac 200B II, Selovac, São Paulo, Brazil), excluding as much air as possible. Orange juice was pressurized, according to the experimental design, in a Stansted Food Lab 9000 (Stansted Fluid Power, Stansted, UK) within a pressure vessel of 500 mL. The maximum nominal operation pressure is 900 MPa and temperature range -20 to 90ºC. The vessel temperature was controlled by water circulation in the outer jacket connected to a heating-cooling system. The pressure transmitting fluid was an ethanol:water solution (70:30, v/v). The compression rate was 7 MPa.s -1 and decompression
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Explorative study of apple juice fluorescence in relation to antioxidant properties

Explorative study of apple juice fluorescence in relation to antioxidant properties

Several methods have been proposed for measuring the antiox- idant activity of individual compounds and the antioxidant capac- ity of foods (Craft et al., 2012). These commonly used assays measure the Trolox equivalent antioxidant capacity (TEAC), oxygen radical absorbance capacity (ORAC), total radical-trapping antioxi- dant parameter (TRAP), ferric-reducing ability of plasma (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical cation (DPPH _) assay (Craft et al., 2012). All these methods rely on measurements of the ability of a food or food component to scavenge specific free radicals or reduce other chemicals. The measured activity is cali- brated against that of a reference compound, usually Trolox (a water-soluble derivative of vitamin E), gallic acid, or catechin.
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Antioxidant Activity of the Extracts from Pycnoporus

Antioxidant Activity of the Extracts from Pycnoporus

The submerged fermentation was carried out in 500 mL flasks containing 150 mL of culture medium prepared with (g/L) 2.4 potato dextrose broth (PDB, HiMedia, India) and 0.1 of bacto- peptone (BD, France), inoculated with approximately 2.0 g of inoculum. It was incubated at 25 °C for 30 days, in the absence of light and under aerobic conditions. The initial pH was not adjusted. The biomass, pH, glucose consumption and antioxidant activity were determined after every five days of cultivation.
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Braz. J. Pharm. Sci.  vol.46 número4

Braz. J. Pharm. Sci. vol.46 número4

The plant Morinda citrifolia L. (noni) has been the focus of many recent studies due to its potential effects on treatment and prevention of several diseases. However, there are few in vivo and in vitro studies concerning its composition and antioxidant capacity. The aim of the present study was to determine the total polyphenol content (TPC) and antioxidant capacity of a juice commercialized as noni juice, but containing grape, blueberry and noni fruits. Commercial noni juice was compared against its separate constituents of blueberry and grape juice. Folin-Ciocalteu and DPPH• methods were used to determine the concentration of total polyphenol content and antioxidant activity, respectively. Commercial noni juice presented higher values of TPC (91.90 mg of gallic acid/100 mL juice) and antioxidant activity (5.85 mmol/L) compared to its 5% diluted constituents. Concentrated blueberry juice presented higher TPC and antioxidant activity than the other juices analyzed. Considering that the blueberry and grape juices account for only 10% in the composition of commercial noni juice, it can be inferred that these two components contribute signiicantly to the antioxidant activity. Therefore, additional studies are necessary in order to elucidate the contribution of the noni juice as an antioxidant.
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Effect of Betula pendula leaf extract on alpha-glucosidase and glutathione level in glucose-induced oxidative stress

Effect of Betula pendula leaf extract on alpha-glucosidase and glutathione level in glucose-induced oxidative stress

Besides their influences on GSH content, natural substances can exert other biological activities which can be beneficial in treatment of diabetes and its complications. For example, due to their antioxidant activity, directly or via their influence on endogenous antioxidants, they can protect cellular targets and consequently the tissues which are most susceptible to diabetic complications [8]. Besides that, they can influence the enzymes which participate in carbohydrate metabolism, such as �-amylase and �-glucosidase, thus retarding the postprandial increase of glucose concentration. Alpha-amylase is an enzyme secreted in saliva and pancreatic juice which catalyzes the hydrolysis of starch to a mixture of smaller oligosaccharides, which are then degraded to glucose by �-glucosidase, enzyme located in the mucosal brush border of the small intestine. Alpha-amylase and �glucosidase inhibitors can thus be helpful in the development of compounds for the treatment of diabetes, obesity, and hyperlipemia. Medicinal plants may constitute a good source of �-amylase and �-glucosidase inhibitors [9, 10].
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Antimutagenic activity of cashew apple ( Anacardium occidentale Sapindales, Anacardiaceae) fresh juice and processed juice ( cajuína ) against methyl

Antimutagenic activity of cashew apple ( Anacardium occidentale Sapindales, Anacardiaceae) fresh juice and processed juice ( cajuína ) against methyl

Cashew apple juice (CAJ), produced from the native Brazilian cashew tree (Anacardium occidentale), and has been reported to have antibacterial, antifungal, antitumor, antioxidant and antimutagenic properties. Both the fresh unpro- cessed juice and the processed juice (cajuína in Portuguese) has been shown to consist of a complex mixture con- taining high concentrations of anacardic and ascorbic acids plus several carotenoids, phenolic compounds and metals. We assessed both types of juice for their antimutagenic properties against the direct mutagens methyl methanesulfonate (MMS) and 4-nitroquinoline-N-oxide (4-NQO) and the indirect mutagen benzo[a]pyrene (BaP) us- ing pre-treatment, co-treatment and post-treatment assays with Salmonella typhimurium strains TA100, TA102, and TA97a. In pre-treatment experiments with strains TA100 and TA102 the fresh juice showed high antimutagenic activ- ity against MMS but, conversely, co-treatment with both juices enhanced MMS mutagenicity and there was an indication of toxicity in the post-treatment regime. In pre-, co-, and post-treatments with TA97a as test strain, antimutagenic effects were also observed against 4-NQO and BaP. These results suggest that both fresh and pro- cessed CAJ can protect the cells against mutagenesis induced by direct and indirect mutagens.
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Differentiation of fresh and processed fruit juices using volatile composition

Differentiation of fresh and processed fruit juices using volatile composition

In sum, fruit aroma is an important indicator, which may reflect the quality of future fruit juice. The contribution of each VOC to the specific aroma signature of each fruit species/types depends on the activity and substrate specificity of the relevant enzymes in the biosynthetic pathway, the substrate availability, the OT above which VOC can be detected by smell, and the presence of the other VOCs [5]. The esters represented more than 45.15% of the total volatile profile of apple, pear, and red fruit juices, which is in accordance with previous studies that report esters as the most abundant chemical group in pear and apple fruit juices [6,7,11,13]. Regarding this chemical group, hexyl acetate, a dominant esters in pear juice, has been reported as possessing a strong pear-like odor [12]. Moreover, ethyl octanoate contributes to sweet and fruit odors in pears, while hexanal, ethyl acetate, hexyl acetate, ethyl butanoate, and butanol are identified as impact volatiles in Conference pears [13]. On the other hand, terpenoids, one of the most dominant chemical groups of VOCs found in orange and grape fruit juices, have shown beneficial functions as well as nutraceutical activities. Recently, some studies in the field of cancer research and food nutrition sciences have been performed on these VOCs due to their potential anticancer properties [44]. Among them, limonene (a dominant VOC in orange juice) has been reported to be a bioactive food component from citrus fruits, with a potential role in breast cancer prevention and treatment [45]. In addition, limonene reduces the oxidative stress in Streptozotocin-induced diabetic rats by decreasing lipid peroxidation and sparing the activities of antioxidant enzymes [46]. Linalool (a dominant VOC in red fruit juice) and terpineol (a dominant in grape fruit juice) are responsible for the fruity and floral notes of food matrices. Moreover, linalool and its degradation product, α-terpineol, have been reported as potent antimicrobial agents against periodontopathic and cariogenic bacteria [47]. Anti-inflammatory effects were also associated with these terpenes [48]. α-Farnesene, a specific terpenoid, with green and herbaceous aroma descriptors, has been reported as the most abundant terpene in fresh apple juice [49], which is in agreement with the results of our study, since we detected GC peak areas ( × 10 6 ) in fresh and processed apple juices of
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Antioxidant and phenolic compounds in sweet potato peels and leaves: food applications and health benefits

Antioxidant and phenolic compounds in sweet potato peels and leaves: food applications and health benefits

From the main food applications found in articles and patents for the period 2003-2014, the development of a flour/powder or a beverage could benefit from the knowledge already built for the tuber. As the strategy of combining different SP plant parts presented a low intensity in the period of time studied, it could be undertaken in future research. Rather than using result means comparison tools as verified for the tuber, the use of design of experiments and multivariate statistical tools during new food development could narrow efficiently the knowledge gap found for peels and leaves. Design responses should include DPPH assay combined with other in vitro antioxidant assays and the determination of phenolic compounds by spectrophotometric methods as well the content of individual anthocyanins and hydroxycinnamic acids. These results could shape further research on health benefits, expected to be related to the reduction of oxidative stress and improvement of brain and liver functions. Although these health benefits could be inferred from the antioxidant activity and phenolic composition of peels and leaves by comparison to the tuber, validation through clinical and preclinical (animal) studies will be necessary. In addition, text mining applied only to abstract texts revealed the main research features of articles and claims of patents on antioxidant activity of phenolic compounds of sweet potato. Dendograms and co-occurrence networks form text mining analysis may be useful to compare future research lines patterns and trends.
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Evaluation of antioxidant activity of grapevine leaves extracts (Vitis labrusca) in liver of Wistar rats

Evaluation of antioxidant activity of grapevine leaves extracts (Vitis labrusca) in liver of Wistar rats

oxidative damage can be induced, and this occurs in some diseases (Dal-Pizzol et al. 2001, 2003). The SOD activity leads to the production of H 2 O 2 , which can react with iron through Fenton reaction to generate hydroxyl radicals, which are considered the most toxic oxygen molecules in vivo (Halliwell and Gutteridge 2007). In this sequence CAT sequesters excessive H 2 O 2 , avoiding its potential role as a facilitator molecule to oxidative stress. Our results suggest that in the groups receiving grapevine leaves extracts, the balance between the enzymes demonstrated a better state of antioxidant protection. This balance was also observed in a study where rats were treated with grape juice V. labrusca against damage generated by CCl 4 in liver tissue (Dani et al. 2007). In the same study this parameter was increased in the CCl 4 group and after the treatment with grape juice, the values were reduced (Dani et al. 2007). These authors reported that this imbalance involves an increase in H 2 O 2 production that in turn reacts with iron through Fenton reaction and thereby produces hydroxyl radicals.
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J. Braz. Chem. Soc.  vol.19 número5

J. Braz. Chem. Soc. vol.19 número5

juice and leaves extracts were identified by HPLC-UV/PAD analysis combined with HPLC microfractionation monitored by TLC using B-carotene and DPPH as the detection reagents. In sugarcane leaves, luteolin-8-C-(rhamnosylglucoside) (1) was the most important compound with radical scavenging activity; in sugarcane juice, the flavones diosmetin-8-C-glucoside (2), vitexin (3) schaftoside (9), isoschaftoside (10) and 4´,5´-dimethyl-luteolin-8-C-glucoside (11) were the most relevant compounds. The content of juice flavonoids (0.241 ± 0.001 mg total flavonoids/mL juice), comparable to other food sources of flavonoids, suggest the potential of sugarcane as a dietary source of natural antioxidants. However, the low antioxidant ability of sugarcane juice (EC 50 = 100.2 ± 2.6 g L -1 ) also points to the need for further studies about the dietary intake of
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ANTIOXIDANT ACTIVITY, ANTHOCYANINS AND ORGANIC ACIDS CONTENT OF GRAPE JUICES PRODUCED IN SOUTHWEST OF MINAS GERAIS, BRAZIL

ANTIOXIDANT ACTIVITY, ANTHOCYANINS AND ORGANIC ACIDS CONTENT OF GRAPE JUICES PRODUCED IN SOUTHWEST OF MINAS GERAIS, BRAZIL

Grape juices were produced experimentally in the Enology Laboratory of the Federal University of Lavras (Lavras, MG, Brazil), using grapes from the 2012/2013 harvest, grown in the same region of southwestern of Minas Gerais in the institutional orchard. Four varieties of red grapes were used in the production of juice: ‘Bordô’ (Vitis labrusca), ‘Isabel Precoce’ (Vitis labrusca), ‘BRS Violeta’ (hybrid) and ‘BRS Rúbea’ (hybrid). After harvesting, grapes were kept in cold storage at 10°C ± 2°C for 12 hours. Then, fruits were sanitized with sodium hypochlorite at 200 mg.L -1 and the seeds were removed manually. Preparation of the grape juice was performed at 75°C ± 5°C for 1 hour, using an artisan equipment by drag steam according to Rizzon, Manfroi and Meneguzzo (1998). For each liter of grape juice, it was added 0.8g of potassium metabisulphite (Synth®, Diadema, Brazil). The potassium metabisulphite was used in order to preserve the product, to contain SO 2 (sulfur dioxide), which has antimicrobial and antioxidant activity. Then, the juice was immediately bottled in glass bottles of 100 ml and maintained under refrigeration (18°C ± 2°C) until analysis.
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IN-VITRO ANTIOXIDANT ACTIVITY OF GOSSYPIUM HERBACEUM  LINN.

IN-VITRO ANTIOXIDANT ACTIVITY OF GOSSYPIUM HERBACEUM LINN.

radicals are called Reactive Oxygen Species (ROS) and they can lead to oxidative damage to cellular components such as proteins, lipids and DNA 1 . Free radicals are reactive molecules involved in many physiological processes such as atherosclerosis, ischaemic heart disease, ageing, inflammation, diabetes, cancer, immunosuppression, neurodegenerative diseases 2,3 . Although several synthetic antioxidants such as butylated hydroxyl anisole (BHA) and butylated hydroxyl toluene (BHT) are available they are quite unsafe 4 . Therefore, in recent year considerable attention has been directed towards identification of natural antioxidants that may be used for human consumption.
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Science of the Total Environment

Science of the Total Environment

varieties and in the experimental conditions. As it can be seen in Table 1, different amounts of phenolic compounds can be extracted from vine shoot from different varieties with similar extraction techniques. In fact, the collected data (Table 1) enable to conclude that the most im- portant factor in the recovery of phenolic compounds is the character- ized vine shoot variety. In a previous study, Çetin et al. (2011) investigated the chemical composition of vine shoots from ten different cultivars from the experimental vineyard of Süleyman Demirel Univer- sity (Isparta, Turkey) after applying a CE very similar to the one applied in the present study (CE conditions: 0.5 g sample, 10 mL of 60:40 etha- nol:water, 30 min at 80 °C with stirring). The reported TPC ranged from 25.36 ± 1.62 to 36.56 ± 2.67 mg GAE/g DW, also demonstrating the in- fluence of vine shoot variety in the amount of extracted phenolic com- pounds. Recently, Rajha and co-workers have focused their effort on the search of green extraction techniques for the recovery of phenolic compounds from vine shoot wastes (Rajha et al., 2014a, b, 2015a, b). Ac- cording to their published studies, a significant enhancement of poly- phenol extraction was reported for vine shoots pre-treated with high- voltage electrical discharge, before applying the alkaline hydrolysis (TPC: 34.5 mg GAE/g DW) (Rajha et al., 2014b). Although the proposed methodology demonstrated the advantage of a pre-treatment with electrical discharges for the extraction of polyphenols, the obtained TPC was in agreement with the values reported in the present study with the environmental-friendly extraction techniques, MAE and SWE, which are less time and energy consuming than the extraction method proposed by Rajha et al. (2014b).
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Vitis vinifera leaves have been traditionally used

Vitis vinifera leaves have been traditionally used

with free access to food and water. The “Principles of laboratory animal care” (NIH publication no. 80-23, re- vised 1996) were followed in all experiments, and our research protocol was approved by the Ethics Commit- tee for Animal Experimentation of Centro Universitá- rio Metodista. All efforts were made to minimize an- imal suffering and to use only the number of animals necessary to produce reliable scientific data. Animals were killed by decapitation without anesthesia and the kidney, liver and heart were rapidly excised on a Petri dish placed on ice. Tissues were weighed and kept chilled until homogenization, which was performed using a ground glass type Potter-Elvejhem homogenizer in 1.5% KCl. The homogenates were centrifuged at 800 g for 10 min at 4 ◦ C, the pellet was discarded and
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Evaluation of antioxidant activity of Melittis melissophyllum L. extracts

Evaluation of antioxidant activity of Melittis melissophyllum L. extracts

in the traditional medicine of central Serbia, due to its sedative properties, for the treatment of nervous anxiety and hysteria (jaric et al., 2007). leaves and inlorescences of this species are used as digestive agents and to treat cough and sore throat. Fresh and dry leaves of M. melissophyllum are used to prepare aromatic tea for drinking as a digestive and antispas- modic (Idolo et al., 2010). he dry calyx parts could be used as lavoring agents in food products as a mushroom aroma enhancer (Maggi et al., 2009). M. melissophyllum ssp. melissophyllum was character- ized by high amount of the mushroom alcohol oct- 1-en-3-ol and the phenolic coumarin with a charac- teristic sweet and creamy vanilla bean odor, playing a major role in the aroma of whole aerial parts (Maggi et al., 2011a).
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Biochemical and histological characterization of tomato mutants

Biochemical and histological characterization of tomato mutants

Biochemical responses inherent to antioxidant systems as well morphological and anatomical properties of photomorphogenic, hormonal and developmental tomato mutants were investigated. Compared to the non-mutant Micro-Tom (MT), we observed that the malondialdehyde (MDA) content was enhanced in the diageotropica (dgt) and lutescent (l) mutants, whilst the highest levels of hydrogen peroxide (H 2 O 2 ) were observed in high pigment 1 (hp1) and aurea (au) mutants. The analyses of antioxidant enzymes revealed that all mutants exhibited reduced catalase (CAT) activity when compared to MT. Guaiacol peroxidase (GPOX) was enhanced in both sitiens (sit) and notabilis (not) mutants, whereas in not mutant there was an increase in ascorbate peroxidase (APX). Based on PAGE analysis, the activities of glutathione reductase (GR) isoforms III, IV, V and VI were increased in l leaves, while the activity of superoxide dismutase (SOD) isoform III was reduced in leaves of sit, epi, Never ripe (Nr) and green lesh (gf) mutants. Microscopic analyses revealed that hp1 and au showed an increase in leaf intercellular spaces, whereas sit exhibited a decrease. The au and hp1 mutants also exhibited a decreased in the number of leaf trichomes. The characterization of these mutants is essential for their future use in plant development and ecophysiology studies, such as abiotic and biotic stresses on the oxidative metabolism.
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BIOLOGICAL CONTROL OF POTATO BLACK SCURF BY RHIZOSPHERE ASSOCIATED BACTERIA

BIOLOGICAL CONTROL OF POTATO BLACK SCURF BY RHIZOSPHERE ASSOCIATED BACTERIA

The present work was carried out to study the potential of plant rhizosphere associated bacteria for the biocontrol of potato black scurf disease caused by Rhizoctonia solani Khun AG-3. A total of twenty-eight bacteria isolated from diseased and healthy potato plants grown in the soil of Naran and Faisalabad, Pakistan were evaluated for their antagonistic potential. Nine bacterial strains were found to be antagonistic in vitro, reduced the fungal growth and caused the lysis of sclerotia of R. solani in dual culture assay as well as in extracellular metabolite efficacy test. The selected antagonistic strains were further tested for the production and efficacy of volatile and diffusible antibiotics, lytic enzymes and siderophores against R. solani. Selected antagonistic bacteria were also characterized for growth promoting attributes i.e., phosphate solubilization, nitrogen fixation and indole acetic acid production. Biocontrol efficacy and percent yield increase by these antagonists was estimated in greenhouse experiment. Statistical analysis showed that two Pseudomonas spp. StT2 and StS3 were the most effective with 65.1 and 73.9 percent biocontrol efficacy, as well as 87.3 and 98.3 percent yield increase, respectively. Potential antagonistic bacterial strain StS3 showed maximum homology to Pseudomonas sp. as determined by 16S rRNA gene sequencing. These results suggest that bacterial isolates StS3 and StT2 have excellent potential to be used as effective biocontrol agents promoting plant growth with reduced disease incidence.
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CYTOTOXIC AND ANTIOXIDANT ACTIVITY OF BUCKWHEAT HULL EXTRACTS

CYTOTOXIC AND ANTIOXIDANT ACTIVITY OF BUCKWHEAT HULL EXTRACTS

Buckwheat contains many prophylactic compounds that are concentrated mainly in outer layers of buckwheat grain. The aim of this study was to prepare buckwheat hull extracts. Ten buckwheat cultivars were screened for their antioxidant and anticancer properties. Total polyphenol content was determined using Folin-Ciocalteau's reagent. Antioxidant activity was established by the method of binding free radical DPPH. Cytotoxic properties were measured on human cervical cancer cells HeLa using mitochondrial cytotoxic test (MTT). Total polyphenol content ranged from 166.67 to 635.31 mg GAE/100 g DW. The highest content displayed tartary buckwheat cultivar Madawaska (0.64% of hulls weight). Among common buckwheat the richest in polyphenols were cultivars Bamby and KASHO-2. The best free radical binding antioxidant activity was found for cultivars with highest polyphenol content. This relationship was not observed for cytotoxic action on human cervical cancer cells. The best growth inhibitory activity on HeLa cancer cells displayed common buckwheat cultivars Bamby and KASHO-2 (up to 50%, extract concentration 100 µg/ml). This was not found for tartary buckwheat cultivar Madawaska.
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