Bioactive components and antioxidant capacities of different miniature tomato cultivars grown by altered fertilizer applications

This study investigated the organic acid and phenolic compound levels, total phenolic (TP) and antioxidant capacity (TEAC) of three miniature tomato cultivars grown on a farmer’s field with three different fertilizer applications. Analysis of phenolic compound (protocatechuic, vanillic, gallic, chlorogenic, caffeic, syringic, p-coumaric and ferulic acid, rutin, quercetin, catechin and phloridzine) organic acid (citric, tartaric, malic, succinic and fumaric acid), TP and TEAC levels in fruit samples showed statistically significant (p?<?0.05) differences between tomato cultivars and fertilizer applications. Rutin and chlorogenic acid were the predominant phenolic compounds found in all three cultivars. The highest rutin value (50.48 mg kg^?1 FW) was found in the Black Zebra fertilized with DAP plus organic and biochemical fertilizers and the lowest (20.52 mg kg^?1 FW) in the Black Zebra fertilized with DAP only. The highest chlorogenic acid value (63.31 mg kg^?1 FW) was found in the sweet pea currant fertilized with DAP only and the lowest (21.06 mg kg^?1 FW) in the Black Zebra fertilized with DAP plus chemical fertilizer. Citric acid content was the dominant organic acid in all three cultivars, with the highest citric acid value (6439.50 mg kg^?1 FW) found in the Sweet Pea Currant cherry tomato fertilized with DAP plus organic and biochemical fertilizers and the lowest (2435.20 mg kg^?1 FW) in the Window Box Yellow fertilized with DAP plus chemical fertilizer. Total phenolic and antioxidant levels in the window box yellow were significantly lower as compared to the Black Zebra and sweet pea currant varieties for all three fertilizer applications.     

Variability in the content of soluble sugars and cell wall polysaccharides in red‐ripe cherry and high‐pigment tomato cultivars

BACKGROUND: Soluble sugars and cell wall polysaccharides are well known for contributing to a range of ‘quality’ characteristics of fresh vegetables such as flavour, texture and healthy properties. Red‐ripe berries of 14 cultivars of cherry tomatoes and four cultivars of high‐pigment tomato hybrids, cultivated in the south of Italy, were analysed for their content of these important qualitative parameters. RESULTS: Sakura appeared to be the cultivar with the highest amount of soluble sugars (53 g kg^?1 fresh weight (f.w.)), mainly glucose and fructose, and, hence the ‘sweetest’ among cherry tomatoes. High‐pigment tomatoes, especially HLY02 and HLY13, showed a soluble sugar content much lower than cherry tomatoes, as expected for industrial, normal‐size tomatoes. Variations in the fructose/glucose ratio, of between 0.68 and 1.48, were evidenced among the different tomato cultivars. Cell wall polysaccharides isolated from whole fresh red‐ripe berries of each cultivar were analysed chemically. The amount of matrix polysaccharides (0.9–3.4 g kg^?1 f.w.) and cellulose (0.16–1.86 g kg^?1 f.w.), as well as their glycosidic composition, showed significant differences among the different cultivars. Cellulose to matrix polysaccharide ratio was highly variable and ranged between 0.06–1.44 and 0.17–0.77 in cherry and high‐pigment tomato cultivars, respectively. CONCLUSION: The differences evidenced in the total soluble sugar and cell wall polysaccharide composition, not only among different types of tomatoes but also different cultivars within the same typology, may play a fundamental role in the quality of tomatoes and deserve further investigations. Copyright © 2008 Society of Chemical Industry     

Effects of genotype and cultivation environment on lycopene content in red‐ripe tomatoes

Lycopene, a natural red pigment found in tomato, is correlated with reduced incidence of some cancers. Forty tomato varieties, including cluster F₁ hybrid tomatoes, round breeding line tomatoes (Lycopersicon esculentum Mill) and cherry tomato types (L esculentum var cerasiforme), grown under greenhouse and field conditions were evaluated for their lycopene content using high‐performance liquid chromatography (HPLC) and spectrophotometry. Lycopene content varied significantly among the tomato varieties, with cherry tomato types having the highest lycopene content. Greenhouse‐grown cluster and round tomatoes contained more lycopene (mean = 30.3 mg kg^?1) than field‐grown tomatoes (mean = 25.2 mg kg^?1), whereas cherry tomato types had a higher lycopene content in field‐grown (mean = 91.9 mg kg^?1) than in greenhouse‐grown (mean = 56.1 mg kg^?1) fruits. HPLC analysis of lycopene isomeric forms revealed a higher content of all‐trans isomers in all tomato genotypes examined. However, the cis isomeric form was exceptionally higher in the field‐ and greenhouse‐grown cherry tomato L esculentum var cerasiforme cv Gardener's Delight, which contained ～9.3 and 9.9 mg kg^?1 cis isomers respectively. Results indicate that genetics and choice of cultivation environment may have a strong influence on tomato lycopene content. Copyright © 2005 Society of Chemical Industry     

Effect of semi-drying on the antioxidant components of tomatoes

Three tomato cultivars (Excell, Tradiro, and Flavourine) grown under hydroponic conditions in a commercial greenhouse in New Zealand were semi-dried at 42 °C. The semi-dried tomatoes contained low levels of 5-hydroxymethyl-2-furfural and were significantly (p < 0.05) darker (lower CIELAB L* values) and had a higher mean a*/b* value (1.6) than the fresh tomatoes (1.2). The mean total phenolics in the semi-dried samples of tomatoes (300 mg gallic acid equivalents, GAE/100 g dry matter (DM)) was significantly lower than that of fresh tomatoes (404 mg GAE/100 g DM). The mean total flavonoid, and lycopene contents in the fresh samples (206 mg rutin equivalents/100 g DM, 63 mg/100 g DM, respectively) also showed a significant decrease after semi-drying (179 mg rutin equivalents/100 g, 54 mg/100 g DM, respectively). Ascorbic acid content in fresh tomatoes (284 mg/100 g DM) decreased to 223 mg/100 g DM after drying. The total antioxidant activity of the semi-dried tomatoes (1783 μmole trolox equivalents antioxidant capacity (TEAC)/100 g DM) was significantly (p < 0.05) lower than that of the fresh samples (2730 μmole TEAC/100 g DM).     

CHARACTERIZATION OF SURFACE AUXIN RESIDUE IN GREENHOUSE TOMATOES (LYCOPERSICON ESCULENTUM)

Greenhouse tomato samples (n = 20) was analyzed before and after peel removal in order to determine surface auxin residue. Mean 4‐CPA residue levels of greenhouse tomatoes with and without peels were 0.383 ± 0.123 mg kg^?1 and 0.241 ±0.085 mg kg^?1, respectively. This difference (36 ±13%) was statistically significant. The frequency distribution curve of tomatoes with peel had a peak point at 4‐CPA reside interval of 0.4‐ < 0.5 mg kg^?1 tomato, and shifted back to 4‐CPA residue interval of 0.2‐ < 0.3 mg kg^?1 for tomatoes without peel. Percentage of samples having 4‐CPA level lower than the critical concentration of 0.5 mg kg^?1 was 80% before peel removal, but increased to 100% upon being peeled. The mean 4‐CPA residue of peels was roughly estimated to be 3.449 mg kg^?1 peel based on peeled versus nonpeeled fruit residue.     

Chemical composition and toxic trace element composition of some Nigerian edible wild mushrooms

Two essential amino acids (methionine and tryptophan); anti‐nutritional factors (tannin and trypsin inhibitor) and toxic elements (Pb, Cd, Ni, As, Hg and Cr) were determined spectrophotometrically from five edible wild mushrooms. The tryptophan content was between 1.00 and 1.82 g (100 g)^?1 but methionine was low at 0.26–1.38 g (100 g)^?1. Tannin content was high (30.3–40.0 mg g^?1) but trypsin inhibitor was low (22.0–39.5 TIU g^?1). Trace elements analysis reviled Pb (0.34–5.06 mg kg^?1) to be the highest of all the trace elements. Cd was (0.06–1.70 mg kg^?1), Ni (0.26–2.08 mg kg^?1), As (0.17–0.92 mg kg^?1), Hg (0.01–0.05 mg kg^?1) and Cr (0.04–0.22 mg kg^?1). These mushrooms are nutritious but must be well processed to eliminate or at least reduce the levels of tannin and Pb to improve their nutritional values.     

Antioxidant activity and phenolic content of lentils (Lens culinaris), chickpeas (Cicer arietinum L.), peas (Pisum sativum L.) and soybeans (Glycine max), and their quantitative changes during processing

Total phenolic content (PC) was ～12 mg g^?1 in lentils, 2.2 mg g^?1 in chickpeas, 2.3 mg g^?1 in soybeans, 2.5 mg g^?1 in yellow peas and 1.2 mg g^?1 in green peas. Total antioxidant activity (AA) determined by ABTS (2,2′‐azinobis‐3‐ethyl‐benzthiazoline‐6‐sulfonic acid) assay was highest in lentils at around 14 μmol Trolox equivalent antioxidant capacity (TEAC) g^?1 and lowest in green peas at 1.9 μmol TEAC g^?1. Bound phytochemicals contributed to 82–85% total AA in lentils. Free phytochemicals contributed more to total AA in chickpeas, yellow peas, green peas and soybeans than bound phytochemicals. AA and PC was reduced by ～80% in lentils and <30% in yellow peas by decortication, by 16–41% in lentils, chickpeas and peas by cooking, and by 22–42% in lentils by soaking. Total AA was significantly correlated with total PC. Soybeans had the greatest ability to scavenge free radicals, inhibit lipid peroxidation and chelate metals among the legumes tested. Different legumes exhibited different AA mechanisms.     

Carotenoids in cassava: Comparison of open-column and HPLC methods of analysis

Cassava leaves and tubers from six cultivars were analysed for carotenoids by both open-column chromatography and high-performance liquid chromatography (HPLC). The major carotenoids of leaves were the non-vitamin A carotenoid lutein (86-290 mg kg^?1 fresh weight (FW)) and the pro-vitamin A carotenoid β-carotene (13-78 mg kg^?1 FW). Immature leaves contained less than mature leaves. Tubers contained 0.1-3 mg kg^?1 FW of β-carotene and 0.05-0.6 mg kg^?1 FW of lutein. Carotenoids present in small amounts included α-, γ-, and §-carotenes and β-cryptoxanthin and others were separated and partially identified. Yellow tubers contain much more β-carotene than white tubers and cassava is a good source of pro-vitamin A carotenoids compared with other root crops. Both methods gave similar results for β-carotene and lutein, but the open-column method did not allow separation and quantitation of carotenoids present in small amounts. HPLC separated many carotenoids, but most peaks could not be identified for lack of reference compounds. A great advantage of open-column chromatography for developing countries is its use of simple equipment and readily available reagents and solvents compared with HPLC, which requires complex equipment needing careful maintenance and expensive solvents. The open-column method is more labour intensive but this is not a constraint in developing countries.     

Phenolics and antioxidative activities in common beans (Phaseolus vulgaris L)

Six bean cultivars grown in southern Manitoba for 2 years were evaluated for variability in yield of millstreams and phenolic constituents. The ethanolic extract of bean cultivars and millstreams was screened for antioxidant activity using the β‐carotene‐linoleate and the 1, 1‐diphenyl‐2‐picrylhydrazyl (DPPH) in vitro model systems. Cultivar was the main source of variation for yield of millstreams, content of phenolic compounds and antioxidant activities. Phenolic compounds in cultivars varied from 3.3 to 16.6 mg catechin equivalent and from 0.15 to 0.32 mg cyanidin‐3‐glucoside equivalent g^?1 bean for total phenolic and anthocyanin contents, respectively. The bean cultivars exhibited antioxidant activity (AA) of 10–46% inhibition of lipid peroxidation in the linoleate and 0.4–1.3 trolox equivalent antioxidant capacities (TEAC) in the DPPH model systems. The hull millstream with maximum concentration of phenolic compounds exhibited the strongest antioxidant activity of 383 µM trolox equivalent g^?1 hull. Total phenolic content, alone or in combination with other phenolic constituents, is a potential candidate as a selection criterion for antioxidant activity in beans. Copyright © 2005 Society of Chemical Industry     

Analyses of tomato peel and seed byproducts and their use as a source of carotenoids

Commercial tomato canning yields two different byproducts. One is the material that results from peeling tomatoes, while the other results from removing the seeds. The peel byproduct contained 100.8 g protein, 256.4 g ash and 299.4 g acid detergent fiber kg^?1. Ash content was high because the peel byproduct contained 83.8 g kg^?1 sodium as a result of using a sodium hydroxide solution to peel the tomatoes. The seed byproduct contained 202.3 g protein, 51.8 g ash, and 537.9 g acid detergent fiber kg^?1. An amino acid analysis of seeds indicated that approximately 60% of the protein results from amino acids. Both byproducts were analyzed for carotenoid content. The lycopene content of peel byproduct was 734 µg g^?1 of dry material. Significant amounts of lutein, β‐carotene, and cis‐β‐carotene were also present. Seed byproduct contained 130 µg lycopene kg^?1 of dry matter. The content of other carotenoids was approximately half of that present in the peels. Peel and seed byproducts were included at 75 g kg^?1 in hen diets to determine the transfer of carotenoids to the yolk. When fed at this concentration, the lycopene content of dry egg yolk was approximately 0.9 µg g^?1. Approximately 0.1% of the lycopene in peel byproduct and approximately 0.7% of the lycopene in the seed byproduct was transferred from the feed to the yolk. Lycopene appears more similar to carotene than to oxycarotenoids in its transfer to the yolk. Copyright © 2005 Society of Chemical Industry     

Total phenol,flavonoid, proanthocyanidin and vitamin C levels and antioxidant activities of Mauritian vegetables

Ten Mauritian vegetables, broccoli, cauliflower, white cabbage, lettuce, Chinese cabbage, mugwort, carrot, onion, tomato and chilli pepper, were analysed for their total phenol, flavonoid, proanthocyanidin and vitamin C contents and antioxidant capacity. Antioxidant activities of the vegetables ranged from 0.43 to 3.68 µmol g^?1 fresh weight Trolox equivalent antioxidant capacity (TEAC) and from 0.60 to 8.47 µmol g^?1 fresh weight ferric reducing antioxidant power (FRAP). Levels of total phenols in the vegetables varied between 132 and 1189 µg g^?1 fresh weight and those of total flavonoids between 45 and 944 µg g^?1 fresh weight, while proanthocyanidins were detected at very low levels in only a few vegetables. Vitamin C contents varied between 25 and 748 µg g^?1 fresh weight. Quercetin was the dominant flavonoid aglycone in the hydrolysed vegetable extracts, with values in the range of 15–390 µg g^?1 fresh weight. There were strong correlations between antioxidant capacity and total phenols (TEAC, r = 0.91; FRAP, r = 0.83) and total flavonoids (TEAC, r = 0.89; FRAP, r = 0.82). Vitamin C contents showed poor correlation with TEAC values (r = 0.33), while no correlation was observed with FRAP values. Highest antioxidant capacities were observed in Chinese cabbage (Brassica chinensis L), onion (Allium cepa L), mugwort (Artemisia vulgaris Cantley) and broccoli (Brassica oleracea L var botrytis L subvar cymosa). Mauritian vegetables therefore represent a significant source of phenolic antioxidants, with quercetin derivatives being most abundant, and this may contribute to their potential health benefits. Copyright © 2004 Society of Chemical Industry     

Evaluation of chemical constituents and antioxidant activity of sweet cherry (Prunus avium L.) cultivars

This research was undertaken to evaluate the sugars, organic acids, phenolic compositions and antioxidant capacities of sweet cherry cultivars (Van, Noir de Guben, Larian and 0‐900 Ziraat) grown in Turkey. High‐performance liquid chromatographic methods were used to identify and quantify four sugars (sucrose, glucose, fructose and sorbitol) and four organic acids (malic, citric, shikimic, and fumaric acid). The major organic acid was found as malic acid (8.54–10.02 g kg^?1 of FW). With regard to sugars, glucose was present in the largest amounts (44.71–48.31 g kg^?1 of FW) for sweet cherry cultivars. The sum of sugars ranged from 103.87 (Larian) to 113.13 g kg^?1 of FW (0‐900 Ziraat) and that of organic acids from 12.01 (0‐900 Ziraat) to 14.17 g kg^?1 of FW (Noir de Guben). A total of eleven phenolic compounds were identified and quantified in sweet cherry cultivars, including hydroxycinnamic acids (3), anthocyanins (5), flavan‐3‐ols (2) and flavonol (1) compounds. Total phenolic contents ranged from 88.72 (Van) to 239.54 (Noir de Guben) mg/100 g of FW, while antioxidant activities ranged from 2.02 to 7.75 μm Trolox equivalents g^?1 of FW.     

Potential bioactive compounds in health promotion from broccoli cultivars grown in Spain

Glucosinolates, phenolic compounds and vitamin C were evaluated in two commercial and 12 experimental cultivars of broccoli (Brassica oleracea L var italica) grown under uniform cultural conditions. The predominant glucosinolates in all broccoli cultivars were 4‐methylsulphinylbutyl glucosinolate (glucoraphanin) and 3‐indolylmethyl glucosinolate (glucobrassicin). Other glucosinolates such as 4‐OH‐glucobrassicin and N‐methoxyglucobrassicin were detected in lower amounts. The total glucosinolate concentration ranged from 3.0 µmol g^?1 dw (dry weight) in Pentathlon (experimental cultivar) to 28.3 µmol g^?1 dw in I‐9905 (experimental cultivar). Flavonoids, caffeic acid derivatives and sinapic acid derivatives were quantified in methanol extracts. The largest content of flavonoids was found in the commercial cultivars Marathon and Lord, around 60 mg kg^?1 fw (fresh weight). The vitamin C content of broccoli ranged from 43.1 mg per 100 g fw in Lord (commercial cultivar) to 146.3 mg per 100 g fw in SG‐4515 (experimental cultivar). © 2002 Society of Chemical Industry     

Phenolic compounds,lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum)

Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p‐coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59 mg kg^?1 fresh weight, while naringenin levels were lower than 12.55 mg kg^?1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32 mg kg^?1 fresh weight, followed by caffeic acid, while p‐coumaric and ferulic acids showed similar concentrations lower than 5 mg kg^?1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50 mg kg^?1 fresh weight), while the concentration in the other varieties was between 50 and 30 mg kg^?1, with the exception of Liso (less than 20 mg kg^?1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry     

Variations in antioxidant properties of strawberries grown in Brazilian savannah and harvested in different seasons

BACKGROUND: Strawberries are nutritive fruits and a source of antioxidants. We evaluated antioxidant properties of ‘Camino Real’ strawberries grown in the Brazilian savannah, harvested in different seasons. Analytical and meteorological data were analyzed by partial least squares regression. RESULTS: Fruits from May showed the lowest contents of total phenolics (1789.78 mg kg^?1 fresh weight (FW)), catechin (21.37 mg kg^?1 FW), quercetins (4.89 mg kg^?1 FW) and total ellagic acid (208.68 mg kg^?1 FW) and the lowest antioxidant activity by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) (11.39 mg Butylated hydroxytoluene (BHT) eq. g^?1 FW) and ferric reducing antioxidant power (FRAP) (22.01 mg ferrous sulfate eq. g^?1 FW) assays. Strawberries harvested in July presented the lowest concentrations of total (190.61 mg kg^?1 FW) and individual anthocyanins (73.88 mg kg^?1 FW and 5.96 mg kg^?1 FW for pelargonidin‐3‐glucoside and cyanidin‐3‐glucoside, respectively), but the highest contents of vitamin C (685.47 mg kg^?1 FW), DPPH (18.87 mg BHT eq. g^?1 FW) and FRAP (39.30 mg ferrous sulfate eq. g^?1 FW). The highest contents of free ellagic acid (26.11 mg kg^?1 FW), pelargonidin‐3‐glucoside (291.82 mg kg^?1 FW) and cyanidin‐3‐glucoside (11.84 mg kg^?1 FW) were found in strawberries from September. Rain in the previous 30 days to harvest influenced negatively many phenolics and antioxidant activity of strawberries harvested in May. In July, longer photoperiod and lower temperature at 30 days previous to harvest probably led to higher antioxidant activity and vitamin C. Increased photoperiod and temperature at the final stage of maturation seem to raise pigments and free ellagic acid in strawberries. CONCLUSION: It was possible to observe significant relationships among meteorological and antioxidant variables for strawberries grown in the Brazilian savannah. Copyright © 2011 Society of Chemical Industry     

Integrated processing of fresh Indian sea buckthorn (Hippophae rhamnoides) berries and chemical evaluation of products

An efficient pilot‐scale process was developed to produce nutraceutical products from fresh sea buckthorn (Hippophae rhamnoides) berries. Fresh berries were subjected to high‐pressure dewatering using a continuous screw press. The separated liquid phase containing 80–90% of pulp oil was clarified at 80 °C and centrifuged to obtain pulp oil, clear juice and sludge. The pulp oil yield was 2.7–2.8% of fresh berry weight with 66–70% extraction efficiency. The pulp oil was remarkably rich in carotenoids (2450–2810 mg kg^?1), tocopherols (1409–1599 mg kg^?1) and sterols (4096–4403 mg kg^?1), with a characteristic fresh berry flavour and 16:1 as the major fatty acid (45.6–49.1%). The clear juice obtained was free from oil and contained high amounts of vitamin C (1683–1840 mg kg^?1) and phytochemicals such as polyphenols (2392–2821 mg kg^?1) and flavonoids (340–401 mg kg^?1). Isorhamnetin (251–310 mg kg^?1) was the major flavonoid in the juice, along with quercetin (77–81 mg kg^?1) and kaempherol (12–16 mg kg^?1). The juice was very acidic (pH 3), with high concentrations of organic acids (30.8–36.0 g kg^?1). High‐performance liquid chromatography profiling of organic acids revealed quinic acid (18.1–19.9 g kg^?1) as the major acid in the juice. The seeds in the pressed cake were separated and extracted for oil using supercritical CO₂. Copyright © 2006 Society of Chemical Industry     

Influence of different crop management practices on the nutritional properties and benefits of tomato ‐Lycopersicon esculentum cv Perfectpeel‐

In this study, we have explored the relationship between the cultivation method and the concentration of major flavonoid aglycones, hydroxycinnamic acids, carotenoids and the total antioxidant activity of tomato (Lycopersicon esculentum cv Perfectpeel); in addition, we have investigated the bioactivity of polyphenol extracts from tomato. The main polyphenols in extracts were quercetin (33.90 ± 6.31 mg kg^?1 and 17.92 ± 1.09 mg kg^?1 in conventional and organic extracts), chlorogenic acid (3.52 ± 0.74 mg kg^?1 and 2.82 ± 0.92 mg kg^?1 in conventional and organic extracts) and caffeic acid (3.61 ± 0.71 mg kg^?1 and 3.29 ± 0.33 mg kg^?1 in conventional and organic extracts). Although statistical differences were found between organic and conventional extracts in several target compounds, no difference in biological effect was observed using cell models. The observed Trans Epithelial Electrical Resistance values were not significantly different between organic and conventional tomato extracts, but we have observed, in both samples, a decrease in tight‐junction permeability at 17 μm of polyphenol concentrations. Antioxidant compounds entering within the cell could exert an antioxidant action, nevertheless at concentrations >17 μm could have a pro‐oxidant effect.     

Antioxidant properties of polar and non‐polar extracts of some tropical green leafy vegetables

BACKGROUND: The higher consumption of vegetables and fruits could be a practical approach to the management of oxidative stress. The present study sought to compare the antioxidant properties of polar and non‐polar constituents of some tropical green leafy vegetables (Struchium sparganophora, Amaranthus cruentus, Telfairia occidentalis, Ocimum gratissimum, Talinium triangulare, Cnidoscolous aconitifolius and Vernonia amygdalina). RESULTS: The polar antioxidant constituents (total phenol (3330–17 572 mg kg^?1), total flavonoid (1668–4306 mg kg^?1) and vitamin C (224–642 mg kg^?1)) were higher than the non‐polar antioxidant constituents (total phenol (703–3115 mg kg^?1), total flavonoid (130–1303 mg kg^?1) and carotenoids (132–1303 mg kg^?1)). Furthermore, the polar extracts had a significantly higher (P < 0.05) 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging ability (except T. triangulare), total antioxidant capacity, reducing power (except T. triangulare and A. cruentus) and Fe(II) chelating ability (except C. aconitifolius and S. sparganophora). However, the polar and non‐polar extract of O. gratissimum had the highest antioxidant properties while that of T. triangulare had the least antioxidant properties. CONCLUSION: The polar extract of most of the vegetables had higher antioxidant properties than the non‐polar extract, with O. gratissimum extracts having the highest antioxidant properties. Copyright © 2008 Society of Chemical Industry     

Migration of epoxidized soybean oil (ESBO) and phthalates from twist closures into food and enforcement of the overall migration limit

Nineteen samples of food in glass jars with twist closures were collected by the national food inspectors at Danish food producers and a few importers, focusing on fatty food, such as vegetables in oil, herring in dressing or pickle, soft spreadable cheese, cream, dressings, peanut butter, sauces and infant food. The composition of the plasticizers in the gaskets was analysed by gas chromatography with flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Epoxidized soybean oil (ESBO) and phthalates were determined in the homogenized food samples. ESBO was the principal plasticizer in five of the gaskets; in 14 it was phthalates. ESBO was found in seven of the food samples at concentrations from 6 to 100 mg kg^?1. The highest levels (91–100 mg kg^?1) were in oily foods such as garlic, chilli or olives in oil. Phthalates, i.e. di-iso-decylphthalate (DIDP) and di-iso-nonylphthalates (DINP), were found in seven samples at 6–173 mg kg^?1. The highest concentrations (99–173 mg kg^?1) were in products of garlic and tomatoes in oil and in fatty food products such as sauce béarnaise and peanut butter. For five of the samples the overall migration from unused lids to the official fatty food simulant olive oil was determined and compared with the legal limit of 60 mg kg^?1. The results ranged from 76 to 519 mg kg^?1 and as a consequence the products were withdrawn from the market.     

Determination of Biogenic Amines in Herby Cheese

Herby cheese (Otlu peynir) is widely produced and consumed in eastern parts of Turkey, and is generally made from sheep milk. The biogenic amines and organic acids content, microbiological, and chemical properties of Herby cheese were determined on 30 samples obtained from retail markets in East Anatolia Region, Turkey. The most important biogenic amines were tyramine (range 18.0–1125.5 mg kg^?1), followed by cadaverine varied from not detected to 1844.5 mg kg^?1. Histamine content generally was found higher than 100 mg kg^?1. The concentration of amines in some cheeses was much higher than the toxic dose limits. Generally, total amine content was found high in samples that had high nitrogen fraction and organic acids value. Levels of biogenic amines were significantly correlated with the organic acids of Herby cheese. The basic organic acid was found the lactic acid ranging from 585.4 to 26480.3 mg kg^?1, followed by butyric acid varying between 314.8 and 7329.6 mg kg^?1 values. Lipolysis and nitrogen fraction were determined high in ripened Herby cheese samples. Coliform counts of samples showed lower than 100 cfu g^?1 in the samples. Significant (p < 0.01) positive correlation was observed between acetic acid and phenylethylamine, putrescine, cadaverin, histamine, and tyramine.