Flavonoids in vegetable foods commonly consumed in Brazil and estimated ingestion by the Brazilian population

Phenolic profiles in leaves of chicory cultivars (Cichorium intybus L.) as influenced by organic and mineral fertilizers

Chicory (Cichorium intybus L.) is a typical Mediterranean vegetable, and it shows great morphological diversity, including different leaf colours. Five cultivars commonly produced in Slovenia ('Treviso', 'Verona', 'Anivip', 'Castelfranco', 'Monivip') were grown in pots under controlled conditions in a glasshouse, with organic and/or mineral fertilizers administered to meet nitrogen requirements. HPLC analysis was carried out to study the phenolic compositions of the leaves. A total of 33 phenolic compounds were extracted from these chicory leaves and were quantitatively evaluated in an HPLC-DAD-based metabolomics study. Among the cultivars, the highest TPC was seen for 'Treviso' (300.1 mg/100 g FW), and the lowest, for 'Castelfranco' (124.9 mg/100g FW). Across the different treatments, the highest TPC was in the control samples (254.3 mg/100 g FW), and the lowest for the organic (128.6 mg/100 g FW) and mineral fertilizer (125.5 mg/100 g FW) treatments. The predominant phenolic compounds in all of the samples were hydroxycinnamic acids, including chlorogenic and cichoric acid. Fertilizer administration provides a discriminant classification of the chicory cultivars according to their phenolic compounds.

Effect of thermal processing and maceration on the antioxidant activity of white beans

Phenolic compounds, which naturally occur in beans, are known to have antioxidant activity, which may be partially lost during the processing of this legume. This study evaluated the effect of thermal processing and maceration on the phenolic acid and flavonoids profile and content and on the antioxidant activity of white beans. According to the results obtained from the 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method, there were no significant differences among treatment groups analysed. When was using 1,1-diphenyl-2-pycrylhydrazyl method (DPPH), beans cooked without maceration present the higher antioxidant activity, and raw beans the lower. The phenolic acids found in greater amounts were gallic acid and chlorogenic acid. Kaempferol was only detected in the soaked and cooked samples; catechin and kaempferol-3-rutinoside were found in the highest concentrations. Quercetin and kaempferol-3-glucoside were not affected by the cooking process, either with or without maceration. In general, the heat treatment increased the antioxidant activity.

Glucosinolates, myrosinase hydrolysis products, and flavonols found in rocket (Eruca sativa and Diplotaxis tenuifolia)

Rocket species have been shown to have very high concentrations of glucosinolates and flavonols, which have numerous positive health benefits with regular consumption. This review highlights how breeders and processors of rocket species can utilize genomic and phytochemical research to improve varieties and enhance the nutritive benefits to consumers. Plant breeders are increasingly looking to new technologies such as HPLC, UPLC, LC-MS, and GC-MS to screen populations for their phytochemical content to inform plant selections. This paper collates the research that has been conducted to date in rocket and summarizes all glucosinolate and flavonol compounds identified in the species. The paper emphasizes the importance of the broad screening of populations for phytochemicals and myrosinase degradation products, as well as unique traits that may be found in underutilized gene bank resources. This review also stresses that collaboration with industrial partners is becoming essential for long-term plant breeding goals through research.

Effects of dietary supplementation of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens

Plant polyphenols, especially flavonoids, are of great interest due to their wide range of biological activities. Quercetin, a ubiquitous flavonoid, is known to have antioxidant and antibacterial effects. In this study, we investigated the effect of quercetin on performance, egg quality, cecal microflora populations, and antioxidant status in laying hens. Two hundred forty 28-wk-old Hessian laying hens, with an average laying rate of lay 85% at the start, were randomly allotted to 4 treatments and fed 1 of 4 diets (negative control, 0.2, 0.4, and 0.6 g of quercetin/kg of diet) for 8 wk. Layer performance responses, egg quality parameters, cecal microflora populations and antioxidant status were measured at the end of the experiment. Results showed that feed conversion decreased as the quercetin level increased. Laying rate had a quadratic correlation with the level of quercetin (P = 0.056) and was maximized by the supplementation level of 0.2 g/kg of diet. However, no significant quercetin effect was observed on egg quality. Regression analysis showed that the population of total aerobes and coliforms decreased and the population of Bifidobacteria increased as the level of quercetin increased. Regression analysis also showed the activities of Cu-Zn-superoxide dismutase increased as the level of quercetin increased (P < 0.05). Results of the study suggest that the appropriate level of supplementation is 0.367 to 0.369 g of quercetin/kg of feed based on the improvement of laying rate (with 88.55 as maximum value) and feed conversion (with 2.0725 as minimum value). Our observations provided further evidence that dietary supplementation of quercetin improved performance by modulation of intestinal environment and liver superoxide dismutase content in laying hens. Quercetin has the potential as functional feed additive in animal production.

Long-term orange juice consumption is associated with low LDL-cholesterol and apolipoprotein B in normal and moderately hypercholesterolemic subjects

BACKGROUND

This study investigated the hypothesis that long-term orange juice consumption (≥ 12 months) was associated with low risk factors for cardiovascular disease in adult men and women with normal and moderately high cholesterol blood levels.

METHODS

The sample consisted of 103 men (18-66 y) and 26 women (18-65 y); all were employees of an orange juice factory with daily access to free orange juice. The results showed that 41% of the individuals consumed 2 cups (480 mL) of orange juice per day for at least twelve months, while 59% of the volunteers are non-consumers of orange juice.

RESULTS

Orange juice consumers with normal serum lipid levels had significantly lower total cholesterol (-11%, p <0.001), LDL-cholesterol (-18%, p < 0.001), apolipoprotein B (apo B) (-12%, p < 0.01) and LDL/HDL ratio (-12%, p < 0.04) in comparison to non-consumers, as did the consumers with moderate hypercholesterolemia: lower total cholesterol (-5%, p <0.02), LDL-cholesterol (-12%, p <0.03), apolipoprotein B (-12%, p <0.01) and LDL/HDL ratio (-16%, p <0.05) in comparison the non-consumers counterparts. Serum levels of homocysteine, HDL- cholesterol and apolipoprotein A-1, body composition and the dietary intake of food energy and macronutrients did not differ among orange juice consumers and non-consumers, but vitamin C and folate intake was higher in orange juice consumers.

CONCLUSION

Long-term orange juice consumers had lower levels of total cholesterol, LDL-cholesterol, apo B and LDL/HDL ratio and an improvement of folate and vitamin C in their diet.

Bioaccumulation of Microcystins in Lettuce

The contamination of lettuce (Lactuca sativa L.) by water-borne crude extracts of the cyanobacterium microcystin-producing Microcystis aeruginosa (Kützing) Kützing was investigated. The aim of the study was to determine whether bioaccumulation of microcystins occurs in lettuce foliar tissue when sprayed with solutions containing microcystins at concentrations observed in aquatic systems (0.62 to 12.5 μg · L(-1) ). Microcystins were found in lettuce foliar tissues (8.31 to 177.8 μg per Kg of fresh weight) at all concentrations of crude extracts. Spraying with water containing microcystins and cyanobacteria may contaminate lettuce at levels higher than the daily intake of microcystins recommended by the World Health Organization (WHO), underscoring the need to monitor such food exposure pathways by public authorities.

Carotenoids and total phenolic contents in plant foods commonly consumed in Korea

Phytochemicals are reported to provide various biological functions leading to the promotion of health as well as the reduced risk of chronic diseases. Fat-soluble plant pigments, carotenoids, are extensively studied micronutrient phytochemicals for their potential health benefits. It is noteworthy that specific carotenoids may be responsible for different protective effects against certain diseases. In addition, each carotenoid can be obtained from different types of plant foods. Considering the fact that the phytochemical content in foods can vary according to, but not limited to, the varieties and culture conditions, it is important to establish a database of phytochemicals in locally produced plant foods. Currently, information on individual carotenoid content in plant foods commonly consumed in Korea is lacking. As the first step to support the production and consumption of sustainable local plant foods, carotenoids and total phenolic contents of plant foods commonly consumed in Korea are presented and their potential biological functions are discussed in this review.

Bioactive compounds and phenolic-linked functionality of powdered tropical fruit residues

Tropical fruit residues consisting of seeds, peels and residual pulp generated as by-products of fruit processing industry were investigated for bioactive compounds, the in vitro antioxidant capacity as well as alpha-glucosidase and alpha-amylase inhibitory activities. Cyanidin, quercetin, ellagic acid (EA) and proanthocyanidins were found in acerola, jambolan, pitanga and cajá-umbu residue powders. Acerola powder had the highest phenolic content (8839.33 mg catechin equivalents (CE)/100 g) and also high-ascorbic acid (AA) concentration (2748.03 mg/100 g), followed by jambolan and pitanga. The greatest 1,1-Diphenyl-2-picrylhydrazyl (DPPH) inhibition was observed for jambolan (436.76 mmol Trolox eq/g) followed by pitanga (206.68 mmol Trolox eq/g) and acerola (192.60 mmol Trolox eq/g), while acerola had the highest ferric reducing antioxidant power (FRAP) assay result (7.87 mmol Trolox eq/g). All fruit powders exhibited enzymatic inhibition against alpha-amylase (IC50 ranging from 3.40 to 49.5 mg CE/mL) and alpha-glucosidase (IC50 ranging from 1.15 to 2.37 mg CE/mL). Therefore, acerola, jambolan and pitanga dried residues are promising natural ingredients for food and nutraceutical manufacturers, due to their rich bioactive compound content.

Evaluation of matrix effect in determination of some bioflavonoids in food samples by LC-MS/MS method

In the present work the LC-MS/MS method with solid phase extraction for simultaneous determination of bioflavonoids rutin, quercetin, hesperidin, hesperetin and kaempferol in some food samples (red onion, orange peel and honey) was developed and the matrix effect accompanying this determination was quantified. The matrix effect evaluated using a postextraction addition method was found to be negative in the range -44 to -0.5%, indicating ionization suppression and strongly depended on bioflavonoid concentration. The observed matrix effect was explained taking into account the co-elution of phenolic acids, in terms of their acid-base and hydrophilic properties. The efficacy of extraction expressed as the absolute recoveries of flavonoids were 88-96%, indicating very good efficiency of extraction. The extracts of food samples obtained either by Soxhlet or ultrasonic extraction were analyzed for bioflavonoid content by the LC-MS/MS method in selected reaction monitoring mode using a triple quadrupole detector and standard addition method, which was found to be the most suitable calibration approach for these samples. The optimized separation was achieved on a Phenomenex Gemini C18 column with gradient elution and mobile phase composition A: 2% acetic acid in water and B: acetonitrile. R(s) values were in the range from 1.3 to 3.1, indicating good selectivity of the method. The obtained results (mg/100g fresh weight) for different bioflavonids were for rutin 0.16, for quercetin in the range 0.65-56, for hesperidin 0.016-24, for hesperetin 0.0068-36.4 and for kaempferol 0.14-1.63 and generally show good agreement with published data. Low detection limits (0.014-0.063 μg/mL) were obtained with acceptable recoveries (86-114%). Total time of analysis was less than 40 min, therefore the proposed method represents significant improvement over existing methods.

Potential dietary sources of ellagic acid and other antioxidants among fruits consumed in Brazil: jabuticaba (Myrciaria jaboticaba (Vell.) Berg)

BACKGROUND

The objectives of this study were (1) to evaluate the content of ellagic acid in fruits consumed by the Brazilian population, including native ones; (2) to further characterize rich sources in relation to ascorbic acid, phenolics contents and in vitro antioxidant capacity; and (3) to study the distribution and effect of ripening stage on ellagitannins content of jabuticaba (Myrciaria jaboticaba). The content of free ellagic acid and ellagic acid derivatives such as ellagitannins was analyzed using high-performance liquid chromatography (HPLC).

RESULTS

Ellagic acid was detected in 10 out of a total of 35 fruits analyzed. The content of free ellagic acid in fruits varied from 0.0028 to 0.085 g kg(-1) (FW) and total ellagic acid varied from 0.215 to 3.11 g kg(-1) (FW). All the seven fruits belonging to the Myrtaceae family evaluated in this study presented high contents of ellagitannins in their composition, with jabuticaba, grumixama and cambuci (all native from Brazil) showing the highest total ellagic acid contents. Jabuticaba, the most consumed in Brazil among those and already adapted to commercial plantations, contained concentrated phenolics compounds, including ellagitannins, in the peel. Anthocyanins (cyanidin derivatives) increased significantly through ripening of jabuticaba and were not present in the pulp or seeds. Samples collected from three different locations during summer, winter and spring had total ellagic contents varying from 1.88 to 3.31 g kg(-1) (FW). The decrease in ellagic acid content with ripening was more accentuated for pulp (eight times) compared to seeds (2.3 times) and peel (2.0 times).

CONCLUSION

These results showed the potential of jabuticaba as dietary source of ellagic acid and reinforced consumption of the whole fruit by the population.

Facilitative effects of Eucommia ulmoides on fatty acid oxidation in hypertriglyceridaemic rats

BACKGROUND

Tea made from Eucommia ulmoides leaves is widely consumed as a health food, since recent studies have revealed various pharmacological effects of the tea, e.g. a hypotriglyceridaemic effect. This study was conducted to elucidate the mechanisms underlying the plasma triglyceride-lowering effect of E. ulmoides leaves.

RESULTS

Rats were divided into four groups: a normal group, a group fed a high-fat/high-fructose diet (untreated group) and two groups fed a high-fat/high-fructose diet and E. ulmoides tea (4 or 20 g L(-1) extract, treated groups). Plasma triglyceride concentrations were reduced in treated groups in a dose-dependent manner compared with the untreated group. DNA microarray analysis revealed that genes involved in hepatic α-, β- and ω-oxidation, mainly related to the peroxisome proliferator-activated receptor α and δ signalling pathway, were up-regulated in the treated group. High-performance liquid chromatography analysis showed that E. ulmoides leaves contain three phytochemicals that make up 60 mg g(-1) of the material and are likely to be the active components.

CONCLUSION

This study indicates that the promotion of fatty acid oxidation, probably by the action of phytochemicals, participates in the ameliorative effect of E. ulmoides leaves on hypertriglyceridaemia. These findings provide the scientific evidence for the functionality of E. ulmoides.

Dietary flavonol and flavone intakes and their major food sources in Chinese adults

The study aimed to estimate dietary flavonol and flavone intakes and investigate major dietary sources by FFQ in Harbin of China. A total of 5,046 volunteers completed a semiquantitative food frequency questionnaire (FFQ). A random subsample of 167 healthy subjects completed the 7 consecutive 24-h dietary recalls and 2 FFQ for assessing the reproducibility and validity of FFQ. The correlation coefficients between 2 FFQ were 0.72 for flavonols and 0.65 for flavones; and between FFQ 2 and the 24-h dietary recall, they were 0.62 for flavonols and 0.58 for flavones. When flavonol and flavone intakes were categorized by quartile, complete and partial agreement ranged from 76% to 84%. The total intake of flavonols and flavones was 19.13 mg/day, and the mean flavonol and flavone intakes were 14.30 mg/day and 4.82 mg/day, respectively. Quercetin was the major contributor (31%) to total intake of flavonols and flavones, followed by kaempferol (22%). The main food sources of flavonols and flavones were apple (12%), potato (8%), celery (7%), eggplant (7%), and actinidia (5%). This work could facilitate the investigation on the proposed relation between these flavonoids and the prevention of chronic diseases.

Protective properties of quercetin against DNA damage and oxidative stress induced by methylmercury in rats

Aim of the study was to find out whether consumption of quercetin (QC), an abundant flavonoid in the human diet, protects against DNA damage caused by exposure to organic mercury. Therefore, rats were treated orally with methylmercury (MeHg) and the flavonoid with doses that reflect the human exposure. The animals received MeHg (30 μg/kg/bw/day), QC (0.5-50 mg/kg/bw/day), or combinations of both over 45 days. Subsequently, the glutathione levels (GSH) and the activities of glutathione peroxidase (GPx) and catalase (CAT) were determined, and DNA damage was measured in hepatocytes and peripheral leukocytes in single cell gel electrophoresis assays. MeHg decreased the concentration of GSH and the activity of GPx by 17 and 12%, respectively and caused DNA damage to liver and blood cells, while with QC no such effects were seen. When the flavonoid was given in combination with MeHg, the intermediate and the highest concentrations (5.0 and 50.0 mg/kg/bw/day) were found to cause DNA protection; DNA migration was reduced by 54 and 65% in the hepatocytes and by 27 and 36% in the leukocytes; furthermore, the reduction in GSH and GPx levels caused by MeHg treatment was restored. In summary, our results indicate that consumption of QC-rich foods may protect Hg-exposed humans against the adverse health effects of the metal.

Café e saúde humana: um enfoque nas substâncias presentes na bebida relacionadas às doenças cardiovasculares

O café é a bebida mais consumida no Brasil e no mundo ocidental. O fato de ser uma bebida tão popular, aliado à sua importância econômica, explica o interesse por estudos sobre o café, desde a sua composição até seus efeitos na saúde humana. Dentre as diversas substâncias presentes na composição química do café, além dos nutrientes, destacam-se a cafeína, os diterpenos cafestol e kahweol e os ácidos clorogênicos, o que faz do café uma importante fonte dietética destes compostos. Muitos estudos têm verificado a influência de seus constituintes na saúde, principalmente a cafeína vs a elevação da pressão arterial; o cafestol e o kahweol vs a dislipidemia; e ácidos clorogênicos vs proteção cardiovascular, por suas propriedades antioxidantes. Este artigo tem como objetivo apresentar de forma sucinta a importância da bebida e sua composição química, os mecanismos fisiológicos envolvidos na elevação da pressão arterial e do colesterol sérico atribuíveis ao café, bem como estudos selecionados que verificaram a associação do consumo da bebida com estas doenças cardiovasculares.

Orange juice improved lipid profile and blood lactate of overweight middle-aged women subjected to aerobic training

OBJECTIVE

This study investigated how consumption of orange juice associated with aerobic training affected serum lipids and physical characteristics of overweight, middle-aged women.

METHODS

The experimental group consisted of 13 women who consumed 500 mL/d of orange juice and did 1h aerobic training 3 times a week for 3 months. The control group consisted of another 13 women who did the same aerobic training program but did not consume orange juice.

RESULTS

At the end of the experiment, the control group lost an average of 15% of fat mass (P<0.05) and 2.5% of weight (P<0.05), whereas the experimental group lost 11% of fat mass and 1.2% of weight (P<0.05). Consumption of orange juice by the experimental group was associated with increased dietary intake of vitamin C and folate by 126% and 61% respectively. Serum LDL-C decreased 15% (P<0.05) and HDL-C increased 18% (P<0.05) in the experimental group, but no significant change was observed in the control group. Both groups improved the anaerobic threshold by 20% (P<0.05), but blood lactate concentration decreased 27% in the experimental group compared to the 17% control group, suggesting that experimental group has less muscle fatigue and better response to training.

CONCLUSIONS

The consumption of 500 mL/d of orange juice associated with aerobic training in overweight women decreased cardiovascular disease risk by reducing LDL-C levels and increasing HDL-C levels. This association also decreased blood lactate concentration and increased anaerobic threshold, showing some improvement in the physical performance.

Antioxidant intakes and food sources in Greek adults

Antioxidants are compounds physiologically produced or provided through the diet with a potential to inhibit the oxidation of important biological molecules, such as proteins, lipids, and DNA. The contemporary Greek diet is still strongly influenced by Mediterranean dietary traditions. The traditional Mediterranean diet (MD) is a plant-based diet with apparently beneficial health properties, to which a high antioxidant content may contribute. To explore this issue in detail, a database of the content of >200 Greek foods and recipes for a wide spectrum of antioxidant compounds and indices (flavonoids, proanthocyannidins, other antioxidant microcomponents, and total antioxidant capacity) was developed. The database enabled the estimation of antioxidant intakes in Greece using the population-based European Prospective Investigation into Cancer and Nutrition study, in which >28,000 Greeks participate. The results of this work suggest that the contemporary MD in the Greek population is a rich source of a variety of antioxidants. These data can be used in studies about the relationship between antioxidant intake and chronic diseases in the Greek population.

Chemical composition and antioxidant/antidiabetic potential of Brazilian native fruits and commercial frozen pulps

Foods provide essential and bioactive compounds with health-promoting properties such as antioxidant, anti-inflammatory, and hypocholesterolemic activities, which have been related to vitamins A, C, and E and phenolic compounds such as flavonoids. Therefore, the aim of this work was to identify potential sources of bioactive compounds through the determination of flavonoids and ellagic acid contents and the in vitro antioxidant capacity and alpha-glucosidase and alpha-amylase inhibitory activities of Brazilian native fruits and commercial frozen pulps. Camu-camu, cambuci, uxi, and tucuma and commercial frozen pulps of cambuci, cagaita, coquinho azedo, and araca presented the highest antioxidant capacities. Cambuci and cagaita exhibited the highest alpha-glucosidase and alpha-amylase inhibitory activities. Quercetin and kaempferol derivatives were the main flavonoids present in most of the samples. Ellagic acid was detected only in umbu, camu-camu, cagaita, araca, and cambuci. According to the results, native Brazilian fruits can be considered as excellent sources of bioactive compounds.

Influence of postharvest processing and storage on the content of phenolic acids and flavonoids in foods

The review is based on the evaluation of electronically collated data published between 2002 to June 2006. It is based on 325 references dealing with the following subclasses of phenolic compounds: hydroxycinnamic and hydroxybenzoic acids, chalcones, flavanones, flavones, flavonols, monomeric flavanols and anthocyanins. Only publications dealing directly with the effects of storage and postharvest processing on the phenolic acid and flavonoid contents of foods were considered. The expectation that the structural diversity even within each subgroup, and the number of different procedures and of different parameters would make finding homogenous tendencies unlikely, has, in most instances, been confirmed. By adding a database Excel table combined with a focused and unified evaluation, specific additional information was rendered accessible and concise. It holds true for most of the subclasses in question that the effect of storage and food processing on the polyphenol content is negligible in comparison to the differences between different varieties of plants. Variety dependence must always be considered, for all classes of compounds.

Antiobesity effects of yerba maté extract (Ilex paraguariensis) in high-fat diet-induced obese mice

Because the potential of yerba maté (Ilex paraguariensis) has been suggested in the management of obesity, the aim of the present study was to evaluate the effects of yerba maté extract on weight loss, obesity-related biochemical parameters, and the regulation of adipose tissue gene expression in high-fat diet-induced obesity in mice. Thirty animals were randomly assigned to three groups. The mice were introduced to standard or high-fat diets. After 12 weeks on a high-fat diet, mice were randomly assigned according to the treatment (water or yerba maté extract 1.0 g/kg). After treatment intervention, plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, and glucose were evaluated. Adipose tissue was examined to determine the mRNA levels of several genes such as tumor necrosis factor-alpha (TNF-alpha), leptin, interleukin-6 (IL-6), C-C motif chemokine ligand-2 (CCL2), CCL receptor-2 (CCR2), angiotensinogen, plasminogen activator inhibitor-1 (PAI-1), adiponectin, resistin, peroxisome proliferator-activated receptor-gamma(2) (PPAR-gamma(2)), uncoupling protein-1 (UCP1), and PPAR-gamma coactivator-1 alpha (PGC-1 alpha). The F4/80 levels were determined by immunoblotting. We found that obese mice treated with yerba maté exhibited marked attenuation of weight gain, adiposity, a decrease in epididymal fat-pad weight, and restoration of the serum levels of cholesterol, triglycerides, LDL cholesterol, and glucose. The gene and protein expression levels were directly regulated by the high-fat diet. After treatment with yerba maté extract, we observed a recovery of the expression levels. In conclusion, our data show that yerba maté extract has potent antiobesity activity in vivo. Additionally, we observed that the treatment had a modulatory effect on the expression of several genes related to obesity.

Effect of different cooking conditions on phenolic compounds and antioxidant capacity of some selected Brazilian bean (Phaseolus vulgaris L.) cultivars

The effects of different cooking conditions such as soaking, atmospheric (100 degrees C) or pressure boiling (121 degrees C), and draining of cooking water following thermal treatment on phenolic compounds and the DPPH radical scavenging capacity from two selected Brazilian bean cultivars (black and yellow-brown seed coat color) were investigated using a factorial design (2(3)). Factors that significantly reduced the total phenolic contents and antioxidant capacity in both cultivars were the soaking and draining stage. Independent of cooking temperature, total phenolics and antioxidant capacities were enhanced in treatments without soaking and where cooking water was not discarded, and this was likely linked to an increase of specific phenolic compounds detected by high performance liquid chromatography such as flavonols and free phenolic acids in both cultivars. Cooking of beans either at 100 or 121 degrees C, without a soaking stage and keeping the cooking water, would be recommendable for retaining antioxidant phenolic compounds.

Effects of grilling on luteolin (3',4',5,7-tetrahydroxyflavone) content in sweet green bell pepper (Capsicum annuum)

The content of luteloin in green bell pepper (Capsicum annuum) produced in Turkey were determined by RP-HPLC with DAD detection. The luteloin (3',4',5,7-Tetrahydroxyflavone) content of green pepper samples were 46.00 +/- 0.76 mg kg(-1) f.w. (average). The alterations of luteloin concentrations with heating process (grilling, közleme) and the loss of luteloin amount were also determined. Luteolin contents of grilled peppers were found as 29.96 +/- 0.96 mg kg(-1) f.w. The method was objective and reproducible for accurate detection of luteloin in green pepper and other pepper varieties.