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1.
BACKGROUND By‐products generated during the processing of plant food can be considered a promising source of dietary fibre as a functional compound. The dietary fibre composition, soluble sugars and antioxidant activity of the extractable polyphenols of pea and broad bean by‐products have been analysed in this study. RESULTS: Total dietary fibre using AOAC methods plus hydrolysis (broad bean pod: 337.3 g kg?1; pea pod: 472.6 g kg?1) is higher (P < 0.05) in both by‐products than with the Englyst method (broad bean pod: 309.7 g kg?1; pea pod: 434.6 g kg?1). The main monomers are uronic acids, glucose, arabinose and galactose in broad bean pods. However, pea pods are very rich in glucose and xylose. The soluble sugars analysed by high‐performance liquid chromatography in both by‐products have glucose as the most important component, followed by sucrose and fructose. The ferric reducing antioxidant power (broad bean pod: 406.4 µmol Trolox equivalents g?1; pea pod: 25.9 µmol Trolox equivalents g?1) and scavenging effect on 2,2‐diphenyl‐1‐picrylhydrazyl radical (EC50 of broad bean pod: 0.4 mg mL?1; EC50 of pea pod: 16.0 mg mL?1) were also measured. CONCLUSIONS: Broad bean and pea by‐products are very rich in dietary fibre, particularly insoluble dietary fibre and their extractable polyphenols demonstrate antioxidant activity. Therefore they might be regarded as functional ingredients. Copyright © 2011 Society of Chemical Industry  相似文献   

2.
The edible part (pulp) of Tamarindus indica L fruit is relatively poor in protein (87.9 g kg?1) and oil (25.3 g kg?1) but the seed is a good source of both (269.3 g kg?1 protein and 109.1 g kg?1 lipid). Both the pulp and seed are good sources of calcium, and the seed of phosphorus, magnesium and potassium. Low levels of phytic acid and heat-labile trypsin inhibitors are present.  相似文献   

3.
The occurrence of aflatoxins (AF) B1, B2, G1, G2 and cyclopiazonic acid (CPA) in feeds, and AFM1 and CPA in milk was determined in dairy farms located in the northeastern region of São Paulo state, Brazil, between October 2005 and February 2006. AF and CPA determinations were performed by HPLC. AFB1 was found in 42% of feed at levels of 1.0–26.4 µg kg?1 (mean: 7.1 ± 7.2 µg kg?1). The concentrations of AFM1 in raw milk varied between 0.010 and 0.645 µg l?1 (mean: 0.104 ± 0.138 µg l?1). Only one sample was above the tolerance limit adopted in Brazil (0.50 µg l?1) for AFM1 in milk. Regarding CPA in feed, six (12%) samples showed concentrations of 12.5–153.3 µg kg?1 (mean: 57.6 ± 48.7 µg kg?1). CPA was detected in only three milk samples (6%) at levels of 6.4, 8.8 and 9.1 µg l?1. Concentrations of aflatoxins and CPA in feed and milk were relatively low, although the high frequency of both mycotoxins indicates the necessity to continuously monitor dairy farms to prevent contamination of feed ingredients.  相似文献   

4.
BACKGROUND: Total phenolics content, antioxidant activity and cytotoxicity of the methanol extracts from leaf parts of 13 Korean traditional salad plants were investigated in order to determine their properties. RESULTS: The highest phenolics content (mg ferulic acid equivalents kg?1 dry weight (d.w.), omit one) was found in methanol extracts from Polygonum aviculare, at 293.7 ± 6.0, followed by Euonymus alatus, at 250.7 ± 3.3, Saxifraga stolonifera, at 125.0 ± 8.1 and Ligularia fischeri, at 122.5 ± 5.9. The methanol plant extracts dose‐dependently increased free radical scavenging activity. Methanol extracts of Polygonum aviculare, Euonymus alatus and Saxifraga stolonifera, at 31 mg kg?1, exhibited the highest 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging activity (%) by 90.8 ± 4.2, 85.7 ± 3.9 and 64.1 ± 3.2, respectively. According to 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, the methanol extracts from Portulaca oleracea (IC50 < 25.0 µg mL?1) showed the highest cytotoxicity against Calu‐6, followed by Plantago asiatica (49.2 µg mL?1) and Osmunda japonica (89.6 µg mL?1). CONCLUSION: Total phenolics content of the tested plant extracts was correlated with the DPPH radical scavenging activity, suggesting the phenolics compounds are contributing to the antioxidant properties of Korean salad plants. The leaf parts of the 13 Korean traditional salad plants described here that are currently used as foods may also provide some benefit to human health, and research into their potential benefits as preventative and/or therapeutic agents is warranted. Copyright © 2008 Society of Chemical Industry  相似文献   

5.
The aim of this research was to determine the fate of aflatoxins (AFs) and fumonisins (FBs) naturally occurring in raw materials (maize grit and malted barley) during four industrial brewing processes. The aflatoxin B1 (AFB1) level in raw materials varied from 0.31 to 14.85 µg kg?1, while the fumonisin B1 (FB1) level (only in maize grit) varied from 1146 to 3194 µg kg?1. The concentration in finished beer ranged from 0.0015 to 0.022 µg l?1 for AFB1 and from 37 to 89 µg l?1 for FB1; the other aflatoxins and fumonisin B2 were not found in beer samples. The average percentage of toxins recovered in finished beer, referring to the amounts contained in raw materials, were 1.5% ± 0.8% for AFB1 and 50.7% ± 4.7% for FB1. These results were mainly due to the different solubility of the two mycotoxins during the mashing process. If raw materials comply with the limits fixed by European Commission Regulations, the contribution of a moderate daily consumption of beer to AFB1 and FB1 intake does not contribute significantly to the exposure of the consumer.  相似文献   

6.
Uronic acid soluble in ethanol/water (4:1 v/v) increased from 9 ± 1 mg kg?1 fresh weight in pulp of unripe banana fruit. Musa (AAA Group, Cavendish subgroup) ‘Williams’, to 53 ± 13 mg kg?1 fresh weight in fruit ripened for 13 days. This increase began within the first 2 days of ripening. Uronic acid soluble in phenol/acetic acid/water (2:1:1 w/v/v) increased from 15 ± 5 to 86 ± 17 mg kg?1 fresh weight during the first 8 days of ripening, accompanied by a decrease in cell wall uronic acid from 10·2 ± 0·8 to 4·4 ± 0·4 g kg?1 fresh weight. Most or all of the uronic acid in extracts of ripe pulp cochromatographed with monogalacturonic acid. The results were consistent with hydrolysis of cell wall polyuronides by exopolygalacturonase (EC 3.2.1.67).  相似文献   

7.
BACKGROUND: Toxicokinetics and recovery studies of dicamba dimethyl amine salt (DDAS) were conducted to obtain more information about its toxicity and tissue retention in farm animals. RESULTS: The minimum oral toxic dose level of DDAS was determined as 1400 mg kg?1 body weight. In the toxicokinetic study, blood DDAS concentration of 55.6 ± 0.59 µg mL?1 (mean ± standard error) was detected at 0.08 h, which peaked to 102.3 ± 5.03 µg mL?1 at 0.25 h, and declined to a minimum of 4.1 ± 0.06 µg mL?1 at 36 h. In recovery studies, DDAS concentration in urine began to increase significantly (P < 0.05) from 12 h, peaked at 24 h and declined from 48 h onwards. Maximum excretion through faeces was at 24 h and was complete by 144 h. The residual level in tissues decreased significantly (P < 0.05) on day 7 as compared to day 4. In histopathological studies, cellular alterations in lungs, liver, kidney, adrenal gland and spleen were found. CONCLUSION: DDAS persists in the body for a shorter period and its major excretory route is through urine. DDAS has lower affinity to accumulate in tissues, and intensity of cellular alterations is not severe after single‐dose oral administration. Copyright © 2009 Society of Chemical Industry  相似文献   

8.
In Mexico, maize tortillas are consumed on a daily basis, leading to possible aflatoxin exposure. In a survey of 396 2-kg samples, taken over four sampling days in 2006 and 2007 from tortilla shops and supermarkets in Mexico City, aflatoxin levels were quantified by HPLC. In Mexico, the regulatory limit is 12?µg?kg?1 total aflatoxins for maize tortillas. In this survey, 17% of tortillas contained aflatoxins at levels of 3–385?µg?kg?1 or values below the limit of quantification (<LOQ) and, of these, 13% were >12?µg?kg?1 and 87% were below the regulatory limit. Average aflatoxin concentrations in 56 contaminated samples were: AFB1 (12.1?µg?kg?1); AFB2 (2.7?µg?kg?1); AFG1 (64.1?µg?kg?1) and AFG2 (3.7?µg?kg?1), and total AF (20.3?µg?kg?1).  相似文献   

9.
The aims of the study were to obtain information about the occurrence of ochratoxin A (OTA) and citrinin (CIT) in cereals harvested in the Czech Republic and to compare two analytical procedures for detecting OTA. A total of 34 cereal samples, including two matrix reference materials (R-Biopharm, Germany), were analysed. The results were compared with the limit for raw cereal grains used as a foodstuff according to Commission Regulation No. 1881/2006, which allows a maximum OTA level of 5 µg kg?1. Compared were two methods based on the high-performance liquid chromatography principle, one using the immunoaffinity columns OchraTest? (VICAM) and the second based on solvent partition (PART), both followed by fluorescence detection. The highest OTA contents were found in two barley samples. According to the method employed, the results for the first sample (malting barley) were VICAM = 31.43 µg kg?1 and PART = 44.74 µg kg?1. For the second sample (feeding barley) they were VICAM = 48.63 µg kg?1 and PART = 34.40 µg kg?1. Two samples of bread wheat had an OTA content approaching the legal limit (VICAM = 4.71 µg kg?1 and PART = 6.03 µg kg?1; VICAM = 4.12 µg kg?1 and PART = 3.95 µg kg?1). CIT was analysed using the PART method only, and its highest content (93.64 µg kg?1) was found for the malting barley sample with high OTA content (44.74 µg kg?1 as analysed using PART).  相似文献   

10.
BACKGROUND: Jellyfish collagen was hydrolysed with trypsin and properase E, and jellyfish collagen peptide (JCP) was purified from the enzymatic hydrolysate using ion exchange chromatography and gel filtration. The antioxidant activity of JCP in a linoleic acid emulsion system, its superoxide anion‐ and hydroxyl radical‐scavenging activities and its copper‐chelating ability were evaluated in vitro. Initial investigations of JCP's ability to inhibit melanogenesis were carried out using cultured B16 melanoma cells. RESULTS: The molecular weight distribution of JCP was from 400 to 1200 Da. Amino acid analysis showed that JCP was rich in Gly, Pro, Ser, Ala, Glu and Asp and had a total hydrophobic amino acid content of 384.2 g kg?1. JCP showed high antioxidant activity (IC50147.8 µg mL?1), superoxide anion‐scavenging activity (IC5021.9 µg mL?1), hydroxyl radical‐scavenging activity (IC5016.7 µg mL?1) and copper‐chelating ability (IC5088.7 µg mL?1) in vitro. It also significantly inhibited intracellular tyrosinase activity, decreased melanin content and enhanced glutathione synthesis (P < 0.05). Furthermore, JCP decreased intracellular cAMP levels and suppressed tyrosinase mRNA expression. CONCLUSION: Based on the results of this study, JCP exerts anti‐melanogenic actions via its antioxidant properties and copper‐chelating ability. JCP could be used as a natural skin‐lightening agent in the medicine and food industries. Copyright © 2009 Society of Chemical Industry  相似文献   

11.
This paper reports an estimate of the dietary intake of lead by children and adults from the Jinhu area in South-eastern China. A duplicate diet approach was used to collect food samples in November and December 2007. The lead content was measured by furnace atomic absorption spectrometry. Median lead intakes for different groups were as follows: children: 1.65 µg(kgbw)?1 day?1; and adults: 1.10 µg(kgbw)?1 day?1. No exposure exceeded the provisional tolerable weekly intake (PTWI) of 25 µg(kgbw)?1 week?1 proposed by the World Health Organization (WHO). However, median and maximum exposure for the children group amounted to 60.8% and 97.2% of the PTWI, respectively, which were higher than those for adults, which were 40.5% and 86.4%, respectively. It was concluded that health risks due to dietary lead intake seem to be high in Jinhu.  相似文献   

12.
One hundred and forty-six samples of animal feed (barley, n = 60; wheat bran, n = 22; wheat dry pulp, n = 29; and canola meal, n = 35) were collected in 2011 from Mashhad (Khorasan, Iran). Aflatoxins (AFs) were determined in these samples after immunoaffinity column clean-up by high-performance liquid chromatography (HPLC) with fluorescence detection. Aflatoxin B1 (AFB1) contamination was found in 28 samples: in five of the barley samples (8.3%) at a mean level of 0.48 µg·kg?1, in two wheat bran samples (9.0%) at a mean level of 0.88 µg·kg?1, in 10 wheat dry pulp samples (34.5%) at a mean level of 0.30 µg·kg?1 and in 11 canola meal samples (31.4%) at a mean level of 0.92 µg·kg?1. AFB1 levels were below the maximum levels of Iran regulations (5 µg·kg?1) and the EU maximum limit (5 µg·kg?1).  相似文献   

13.
The edible part (pulp) of ripe Dialium guineense fruit is sweet (total sugars 582.1 g kg?1) but acidic (pH 3.3) and relatively poor in protein (61.3 g kg?1) and oil (700 g kg?1), Fairly low levels of ascorbic acid and tannin are present. The seed, however, is mildly acidic (pH 5.5), poor in oil (60.1 g kg?1) but a fairly good source of protein (148.8 g kg?1) and minerals.  相似文献   

14.
A comparison study of different extraction and clean-up procedures for the liquid chromatographic analysis of fumonisins B1 (FB1) and B2 (FB2) in corn masa flour was performed. The procedures included extraction (heat or room temperature) with acidic conditions or EDTA-containing solvents, and clean-up by immunoaffinity or C18 solid-phase extraction columns. Thereafter an analytical method was optimised using extraction with an acidic mixture of methanol–acetonitrile–citrate/phosphate buffer, clean-up through the immunoaffinity column and determination of fumonisins by liquid chromatography with automated pre-column derivatisation with o-phthaldialdehyde reagent. Recovery experiments performed on yellow, white and blue masa flours at spiking levels of 400, 800 and 1200?µg?kg?1 FB1 and of 100, 200 and 300?µg?kg?1 FB2 gave overall mean recoveries of 99% (±6%) for FB1 and 88% (±6%) for FB2. Good recoveries (higher than 90% for both FB1 and FB2) were also obtained with corn tortilla chips. The limits of quantification of the method (signal-to-noise ratio of 10) were 25?µg?kg?1 for FB1 and 17?µg?kg?1 for FB2. The method was tested on different commercial corn masa flours as well as on white and yellow corn tortilla chips, showing fumonisin contamination levels (FB1?+?FB2) up to 1800?µg?kg?1 (FB1?+?FB2) in masa flour and 960?µg?kg?1 in tortilla chips. Over 30% of masa flours originating from Mexico exceeded the European Union maximum permitted level.  相似文献   

15.
BACKGROUND: Cryptococcus laurentii is a well‐known postharvest yeast antagonist. N6‐benzyladenine (6‐BA), a cytokinin plant hormone, has a role in retarding ripening and senescence of harvested produce. This study was conducted to evaluate the efficacy of C. laurentii and 6‐BA in reducing the blue mould disease of apple fruit. RESULTS: The combination of C. laurentii with 6‐BA (20 µg mL?1) was more effective in suppressing the Penicillium expansum infection in apple fruit wounds than C. laurentii alone, although 6‐BA (20 µg mL?1) alone neither affected the growth of C. laurentii nor reduced the incidence of the blue mould disease in vivo. Moreover, treatment of apple fruit with C. laurentii and 6‐BA (20 µg mL?1) resulted in stimulation of superoxide dismutase activity but in inhibition of the increase in peroxidase activity. CONCLUSION: 6‐BA (20 µg mL?1) could enhance the efficacy of C. laurentii in reducing the postharvest blue mould disease of apple fruit, which offered great potential in minimizing the postharvest decay of apple fruit in an integrated pest management strategy. Copyright © 2008 Society of Chemical Industry  相似文献   

16.
Potato crisps are one of the food commodities that contribute most to overall dietary human exposure of acrylamide. This investigation has estimated the dietary exposure to acrylamide form potato crisps in the Spanish population. Sampling of potato crisps (n = 36) from 16 different producers were carried out in March 2008. An average level of 740 µg kg?1 (ranging from 81 to 2622 µg kg?1; minimum to maximum) and a median of 592 µg kg?1 were obtained. Acrylamide levels in marketed potato crisps have been significantly reduced (nearly to 50%) compared with a previous sampling performed 4 years earlier. The observed signal value (90th percentile) was 1377 µg kg?1 with 86% of the samples with acrylamide levels lower than 1000 µg kg?1. Dietary exposure to acrylamide from potato crisp consumption in the total Spanish population was estimated to be 0.042 µg kg?1 body weight day?1 by using a deterministic approach based on the National consumption database. In a second study, dietary exposure (based on a 3-day food record) was determined to be 0.053 µg kg?1 body weight day?1 for the adult population (17–60 years) and 0.142 µg kg?1 body weight day?1 for children (7–12 years). The contribution of potato crisps to the estimated dietary acrylamide exposure of the Spanish population is moderate as compared with other European Member States.  相似文献   

17.
Research reports on the ethnomedical and pharmacological potential of Kigelia africana extracts. In this study, the nutritional potential of K. africana seed and seed oil was evaluated by chemical analyses. Organic matter and ash constituted 915.23 ± 7.98 g kg?1 DM and 49.05 ± 4.55 g kg?1 DM of the seed mass, respectively. Oil constituted 492.2 g kg?1 DM of the seed mass with oleic acid, linoleic acid and α‐linolenic acid constituting 17.6%, 12.9% and 54.3%, respectively, of the seed oil. Vitamin E concentration was 0.94 ± 0.25 μg g?1. Crude protein was 357.35 ± 3.39 g kg?1 DM. Arginine (6.14 ± 0.31 g per 100 g) as the most abundant amino acid and hydroxyproline (0.11 ± 0.06 g per 100 g) the least. Phosphorus (1123.2 mg per 100 g) and calcium (56.1 mg per 100 g) were, respectively, the most and least abundant minerals. Gross energy was 29.6 ± 0.06 MJ kg?1. Kigelia africana seeds could be exploited as nutrient‐dense dietary supplement rich in protein, oleic acid and essential fatty acids.  相似文献   

18.
A total of 178 milk samples (94 of buffalo and 84 of cow) were randomly taken from Punjab and the North West Frontier Province (NWFP) of Pakistan (n?=?89 in each province) and analysed for the presence of aflatoxin M1 (AFM1) by HPLC-FLD. From Punjab about 46% of buffalo's and 49% of cow's milks were contaminated with AFM1 as compared with 52% and 51% for milk samples from NWFP, respectively. Overall, the mean AFM1 concentration was 0.046?µg?kg?1 with a maximum of 0.350?µg?kg?1. All samples complied with the Codex Alimentarius limit of 0.50?µg?kg?1 for AFM1 in milk, but 16.3% of samples exceeded the European Union maximum level of 0.05?µg?kg?1. Another set of 415 buffalo's and cow's milk samples (213 morning milks and 202 evening milks) were analysed. Statistical analysis revealed significant differences (p?<?0.05) between mean AFM1 concentrations in milk during the morning (0.043?µg?kg?1) and the evening (0.028?µg?kg?1) lactation times.  相似文献   

19.
Two microbiological kits based on Bacillus stearothermophilus (Eclipse 50® and Premi®Test) have been evaluated and validated according to the European guideline for the validation of screening methods (January 2010) and in relation to the concentrations recommended by the EU-RL in 2007. Both tests are robust, a fast method and easy to implement. Both tests are applicable to a very large variety of honeys from different floral and geographical origins (rosemary, lavender, scrub, heath, alder, forest, lemon, acacia, chestnut, raspberry, mountain and flowers) as well as honey of different colours (from blank honey to brown honey, including yellow and orange honey). A satisfactory false-positive rate of 5% was obtained for the Eclipse 50® test. The observed detection capabilities CCβ of the Eclipse 50® kit were: chlortetracycline (>75?µg?kg?1), oxytetracycline (≤200?µg?kg?1), tetracycline (>100?µg?kg?1), cloxacillin (≤40?µg?kg?1), tylosin (≤200?µg?kg?1), desmycosin (>400?µg?kg?1), sulfadiazine (≤300?µg?kg?1), sulfadimethoxine (≤250?µg?kg?1), sulfamerazine (>300?µg?kg?1), sulfamethazine (>1000?µg?kg?1), sulfamethizole (>75?µg?kg?1), sulfamethoxazole (≤25?µg?kg?1), sulfanilamide (?1000?µg?kg?1), sulfaquinoxaline (>75?µg?kg?1), sulfathiazole (≤250?µg?kg?1) and lincomycin (>1500?µg?kg?1). These levels were all higher than the recommended concentrations where they exist. Due to its lack of sensitivity, it cannot be recommended for reliable routine use. The observed CCβ of the Premi®Test kit were: chlortetracycline (10?µg?kg?1), oxytetracycline (>10?µg?kg?1), tetracycline (≤10?µg?kg?1), cloxacillin (≤5?µg?kg?1), tylosin (≤10?µg?kg?1), desmycosin (≤15?µg?kg?1), sulfadiazine (≤25?µg?kg?1), sulfadimethoxine (≤25?µg?kg?1), sulfamerazine (≤25?µg?kg?1), sulfamethazine (≤25?µg?kg?1), sulfamethizole (≤25?µg?kg?1), sulfamethoxazole (≤10?µg?kg?1), sulfanilamide (≤25?µg?kg?1), sulfaquinoxaline (≤10?µg?kg?1), sulfathiazole (25?µg?kg?1) and lincomycin (≤25?µg?kg?1). The Premi®Test kit could be recommended for reliable use in routine control due to its low detection capabilities (except for aminoglycosides), but the disadvantage is a high false-positive rate of 14%.  相似文献   

20.
A survey was conducted to determine the occurrence of fumonisin B1, B2 and B3 during 2007 in 186 samples of organic and conventional locally available corn products. Samples included baby food (n = 62), corn flour (11), cornflakes (23), pasta (14), cookies (17) and other corn products (59) were obtained from popular markets of Valencia (Spain) and Perugia (Italy). The analytical method used pressurized liquid extraction and liquid chromatography/electrospray ionization tandem mass spectrometry with a triple quadrupole (QqQ) analyser. Of the 104 Spanish samples, 22% contained levels in the range of 2–449 µg kg?1, 2–229 µg kg?1 and 6–105 µg kg?1 for FB1, FB2 and FB3, respectively, while 19 (23%) of the 82 Italian samples were positive with quantifiable levels between 2–235 µg kg?1, 3–187 µg kg?1, and 4–40 µg kg?1 for fumonisins B1, B2 and B3, respectively. Overall, none of the Italian samples and only one organic baby food sample from a Spanish market was above the maximum permitted levels established by European legislation. Fumonisins were found mostly in corn flour followed by cookies and cornflakes. Eleven samples from Spain and nine samples from Italy were organic products, being contaminated the 72% and 77% of the samples, respectively. Analysis of the results showed that levels of fumonisins in corn products were similar in Italy and Spain. The safety of fumonisin intake through corn products was demonstrated by the calculation of the estimated daily intake of both populations considering organic and conventional products separately, which ranged from 1.7 × 10?3 to 0.72 µg kg?1 bw day?1 and comparing them with the provisional maximum total daily intake (PMTDI) of 2 µg kg?1 bw day?1 established by the European Union.  相似文献   

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