Removal of anti-nutritional factors of rapeseed protein isolate (RPI) and toxicity assessment of RPI.

We prepared a detoxified rapeseed protein isolate (RPI) by phytase/ethanol treatment based on alkaline extraction and acidic precipitation. Contents of protein, fat, ash, moisture, crude fiber, glucosinolates, phytic acid, and phenolics and color were determined. To evaluate the safety of detoxified RPI, five groups of C57 mice (detoxified RPI [10 and 20 g kg-1]; commercial soybean protein isolate (SPI) [10 g kg-1]; non-detoxified RPI [10 g kg-1]; control) were used in the acute-toxicity test. Bodyweight and pathology parameters were recorded at different time points, followed by macroscopic examination, organ-weight measurement and microstructure examination. After pretreatment of rapeseed meals with phytase (enzyme : substrate ratio, 1 : 5 mg g-1) for 1.5 h and two-time ethanol extraction for precipitated protein, the chemical characteristics in RPI were protein (88.26%), fat (0.57%), ash (2.72%), moisture (1.90%), crude fiber (0.77%), glucosinolates (0 µmol g-1), phytic acid (0.17%), phenolics (0.36%) and whiteness (73.38). Treatment resulted in significant removal of anti-nutritional factors (ANFs) and increased whiteness in detoxified RPI compared with non-detoxified RPI, and lower than in cruciferin-rich canola protein isolate (Puratein®). Experimental-related effects on bodyweight, clinical observations, or clinicopathology, in mice treated with detoxified RPI were not observed except for a decreased thyroid gland/parathyroid gland index in mice treated with non-detoxified RPI. Furthermore, the no-observed-effect level (NOEL) was 10 g kg-1 of detoxified RPI, whereas the no-observed-adverse-effect-level (NOAEL) was the highest fed level of 20 g kg-1 of detoxified RPI. Overall, detoxified RPI prepared by the combined treatment of phytase and ethanol was considered safe under the conditions tested, in which the contents of the main ANFs were reduced significantly.

Rapid and Cost-Effective Quantification of Glucosinolates and Total Phenolic Content in Rocket Leaves by Visible/Near-Infrared Spectroscopy.

The potential of visible-near infrared spectroscopy to predict glucosinolates and total phenolic content in rocket (Eruca vesicaria) leaves has been evaluated. Accessions of the E. vesicaria species were scanned by NIRS as ground leaf, and their reference values regressed against different spectral transformations by modified partial least squares (MPLS) regression. The coefficients of determination in the external validation (R²VAL) for the different quality components analyzed in rocket ranged from 0.59 to 0.84, which characterize those equations as having from good to excellent quantitative information. These results show that the total glucosinolates, glucosativin and glucoerucin equations obtained, can be used to identify those samples with low and high contents. The glucoraphanin equation obtained can be used for rough predictions of samples and in case of total phenolic content, the equation showed good correlation. The standard deviation (SD) to standard error of prediction ratio (RPD) and SD to range (RER) were variable for the different quality compounds and showed values that were characteristic of equations suitable for screening purposes or to perform accurate analyses. From the study of the MPLS loadings of the first three terms of the different equations, it can be concluded that some major cell components such as protein and cellulose, highly participated in modelling the equations for glucosinolates.

Metabolomic assessment reveals an elevated level of glucosinolate content in CaCl2 treated broccoli microgreens.

Preharvest calcium application has been shown to increase broccoli microgreen yield and extend shelf life. In this study, we investigated the effect of calcium application on its metabolome using ultra-high-performance liquid chromatography with mass spectrometry. The data collected were analyzed using principal component analysis and orthogonal projection to latent structural discriminate analysis. Chemical composition comparison shows that glucosinolates, a very important group of phytochemicals, are the major compounds enhanced by preharvest treatment with 10 mM calcium chloride (CaCl2). Aliphatic glucosinolates (glucoerucin, glucoiberin, glucoiberverin, glucoraphanin, pentyl glucosinolate, and hexyl glucosinolate) and indolic glucosinolates (glucobrassicin, neoglucobrassicin, and 4-hydroxyglucobrassicin) were increased significantly in the CaCl2 treated microgreens using metabolomic approaches. Targeted glucosinolate analysis using the ISO 9167-1 method was further employed to confirm the findings. Results indicate that glucosinolates can be considered as a class of compounds that are responsible for the difference between two groups and a higher glucosinolate level was found in CaCl2 treated groups at each time point after harvest in comparison with the control group.

Selenium, putrescine, and cadmium influence health-promoting phytochemicals and molecular-level effects on turnip (Brassica rapa ssp. rapa).

The effects of selenium, putrescine, and cadmium on the contents of glucosinolates, total phenolics, flavonoids, carotenoids, chlorophyll, anthocyanin, malondialdehyde, hydrogen peroxide, and antioxidant capacities as well as gene regulation of phenolics, flavonoids, carotenoids, and glucosinolates biosynthesis were investigated in turnip plants. Selenium dioxide (SeO2) treatment significantly induced the amount of gluconasturtiin, glucobrassicanapin, glucoallysin, glucobrassicin, 4-methoxyglucobrassicin, and 4-hydroxyglucobrassicin. Cadmium chloride (CdCl2)- and putrescine-treated plants had considerably enhanced gluconasturtiin and 4-hydroxyglucobrassicin levels, respectively. Total phenolic and flavonoid content as well as antioxidant capacities were significantly increased in SeO2-treated plants. Lutein was higher in control plants followed by, in decreasing order, SeO2-, putrescine-, and CdCl2-treated plants. The chlorophyll content was significantly decreased and anthocyanin, MDA, and H2O2 levels were significantly increased with CdCl2 treatment. Moreover, plants treated with selenium and cadmium showed significant induction of genes related to glucosinolate, phenolic, and carotenoid biosynthesis. These results demonstrated that SeO2 significantly increased the contents of health-promoting compounds and enhanced the antioxidant capacities of turnip plants.

Antioxidant capacity of broccoli sprouts subjected to gastrointestinal digestion.

BACKGROUND: Broccoli is a common vegetable recognized as a rich source of antioxidants. To date, research on the antioxidant properties of broccoli, predominantly conducted on extracts, has not considered the lesions of composition and this activity after gastrointestinal digestion. Here the stability of antioxidants during gastrointestinal digestion was evaluated in conjunction with the protective effects of broccoli sprouts (BS) against oxidative stress in human colon cells. RESULTS: The obtained data suggest that, among the biocompounds identified in BS, glucosinolates were mainly degraded under gastrointestinal digestion, while phenolics, particularly hydroxycinnamic acid derivatives, were the most resistant constituents. The antioxidant capacity of BS extract subjected to gastrointestinal digestion was similar to or higher than that determined for non-digested BS. Gastrointestinal digested BS extract exhibited reactive oxygen species (ROS)-inhibitory capacity in NCM460 human colon cells, with 1 mg mL(-1) showing an ROS clearance of 76.59%. A 57.33% reduction in oxidative DNA damage in NCM460 cells due to treatment with digested BS extract was observed. CONCLUSION: The results lend support to the possible application of BS as a rich source of antioxidants to improve the defensive system against oxidative stress in the human colon mucosa.

Profiling of glucosinolates and flavonoids in Rorippa indica (Linn.) Hiern. (Cruciferae) by UHPLC-PDA-ESI/HRMS(n).

An UHPLC-PDA-ESI/HRMS(n) profiling method was used to identify the glucosinolates and flavonoids of Rorippa indica (Cruciferae), a wild vegetable and Chinese herb used to treat cough, diarrhea, and rheumatoid arthritis. Thirty-three glucosinolates, more than 40 flavonol glycosides, and 18 other phenolic and common organic compounds were identified. The glucosinolates and polyphenols were separated by UHPLC. High-resolution deprotonated molecules provided high accuracy mass values that were used to determine formulas and provide putative identification of the glucosinolates and flavonoids. The fragments from multistage mass spectrometry were used to elucidate the structures. The concentrations of the main components were based on UV peak areas and molar relative response factors with a single calibration standard. This study found this plant to be a rich source for glucosinolates, containing 24 new glucosinolates, including 14 glucosylated glucosinolates that were previously unidentified.

Evaluation of Camelina sativa (L.) Crantz meal as an alternative protein source in ruminant rations.

BACKGROUND: Camelina sativa (CS) is an oilseed crop used for biofuel production. By-products from oil extraction are high in protein and can be used in ruminant rations; more information about their nutritive value is required also considering the antinutrional factor content of the by-products. The aim of this study was to evaluate the nutritive value of CS meal genotypes in comparison with canola. RESULTS: Ten CS genotypes and one canola cultivar were evaluated. Meals were obtained from seeds after solvent oil extraction. CS average crude protein (CP) content (g kg⁻¹ dry matter) was 457. Numerical differences in lysine and sulfur amino acid content were observed among CS genotypes. Glucosinolate (mmol kg⁻¹) content was higher for CS (23.1) than canola (7.2). Sinapine content (g kg⁻¹) was lower for CS (2.79) than for canola (4.32). Differences were observed among CS genotypes for rumen undegraded protein (RUP). Average RUP (g kg⁻¹ CP) was 316 for CS and 275 for canola. CONCLUSIONS: CS meal has potential for use in ruminant rations as a high-quality protein source. In vivo studies are needed to compare CS with other protein sources used in cattle rations. Implementation of breeding programs for improved meal quality is recommend.

Assessment of the anticancer compounds Se-methylselenocysteine and glucosinolates in Se-biofortified broccoli (Brassica oleracea L. var. italica) sprouts and florets.

Broccoli (Brassica oleracea L. var. italica) is a rich source of chemopreventive compounds. Here, we evaluated and compared the effect of selenium (Se) treatment on the accumulation of anticancer compounds Se-methylselenocysteine (SeMSCys) and glucosinolates in broccoli sprouts and florets. Total Se and SeMSCys content in sprouts increased concomitantly with increasing Se doses. Selenate was superior to selenite in inducing total Se accumulation, but selenite is equally effective as selenate in promoting SeMSCys synthesis in sprouts. Increasing sulfur doses reduced total Se and SeMSCys content in sprouts treated with selenate, but not in those with selenite. Examination of five broccoli cultivars reveals that sprouts generally have better fractional ability than florets to convert inorganic Se into SeMSCys. Distinctive glucosinolate profiles between sprouts and florets were observed, and sprouts contained approximately 6-fold more glucoraphanin than florets. In contrast to florets, glucosinolate content was not affected by Se treatment in sprouts. Thus, Se-enriched broccoli sprouts are excellent for simultaneous accumulation of chemopreventive compounds SeMSCys and glucoraphanin.

A new method for measuring relative growth rate can uncover the costs of defensive compounds in Arabidopsis thaliana.

*Most plants suffer some degree of herbivore attack and many actively defend themselves against such an event. However, while such defence is generally assumed to be costly, it has sometimes proved difficult to demonstrate the costs of defensive compounds. *Here, we present a method for analysing growth rates which allows the effects of variation in initial plant size to be properly accounted for and apply it to 30 lines from a recombinant inbred population of Arabidopsis thaliana. We then relate different measures of relative growth rate (RGR) to damage caused by a specialist lepidopteran insect and to levels of putative defensive compounds measured on the same lines. *We show that seed size variation within the recombinant inbred population is large enough to generate differences in RGR, even when no other physiological differences exist. However, once size-standardized, RGR was positively correlated with herbivore damage (fast-growing lines suffered more damage) and was negatively correlated with the concentration of several glucosinolate compounds. *We conclude that defensive compounds do have a growth cost and that the production of such compounds results in reduced herbivore damage. However, size standardization of RGR was essential to uncovering the growth costs of defensive compounds.

Broccoli-derived by-products--a promising source of bioactive ingredients.

UNLABELLED: The regular dietary intake of broccoli on a weekly basis has been related to better health, but industrial use of broccoli by-products (crop remains) is negligible. Adding value to broccoli by-products in a country such as Spain, one of the main broccoli producers for the EU, is of scientific and economic interest. The present article is focused on the bioactive compounds (glucosinolates, phenolic acids, and flavonoids) and nutrients (vitamin C, minerals, and trace elements), as well as the in vitro radical-scavenging capacity (DPPH. test), of the broccoli products (harvest remains) resulting from greenhouse cultivation using 80 mM NaCl treatment, representative of the currently available irrigation water in the production areas of Murcia (SE Spain). The bioactive compounds and nutrient contents varied according to the cultivar, organ (leaves or stalks), and the saline stress (80 mM NaCl), in the cultivars Marathon, Nubia, and Viola. Cultivar Nubia was not affected dramatically by 80 mM NaCl and the contents of phytochemicals and nutrients in the by-products of Nubia fell within the range of health-promoting levels of edible commercial parts (inflorescences or flower heads). Therefore, adding value to broccoli agrowaste by obtaining bioactive ingredients and nutrients could benefit the food and drug industry. PRACTICAL APPLICATION: Many by-products of the agrifood industry may be useful as sources of nutrients and potentially functional ingredients, giving the opportunity to obtain added-value products. Previous studies have been focused on edible florets, but in this case we are interested in adding value to broccoli by-products that represent a real problem in the production sites because no intended use for this material has been envisaged. Therefore, the aim of this study was to add value to the broccoli-derived by-products, since recycling all this agrowaste to obtain bioactive ingredients for industry can boost profits and reduce costs and environmental problems.

The glucosinolate-myrosinase system in nasturtium (Tropaeolum majus L.): variability of biochemical parameters and screening for clones feasible for pharmaceutical utilization.

Leaves of Tropaeolum majus L. contain high amounts of the glucosinolate glucotropaeolin. They are used in traditional medicine to treat infections of the urinary tract. When Tropaeolum leaves are consumed, glucotropaeolin is hydrolyzed to yield mustard oils, which are absorbed in the intestine and excreted in the urine, exhibiting their antimicrobial activity. For a corresponding phytopharmacon, a sufficiently high glucotropaeolin concentration is required and any degradation of glucosinolates while drying must be minimized, i.e. the post mortal cleavage by myrosinases, which are activated by ascorbic acid. In extensive screenings, the dominant parameters determining the glucotropaeolin content in the dried leaves were quantified. It turned out that the glucotropaeolin concentration in the dried leaves represented the most suitable screening parameter. The screening of several hundred Tropaeolum plants resulted in the selection of eight high-yield varieties, from which in vitro plants had been generated and propagated as a source for large field trials.

Nutritional assessment of genetically modified rapeseed synthesizing high amounts of mid-chain fatty acids including production responses of growing-finishing pigs.

The nutritive value of genetically modified myristic acid-rich rapeseed, in which a acyl-thioesterase gene inserted, was studied. Crude nutrients, amino acid and fatty acid profiles as well as mineral and glucosinolate contents were determined and compared with those of the non-transgenic parental cultivar. The concentration of crude nutrients, minerals and amino acids were found to be within the range of natural variance. The myristic and palmitic acid content increased from 0.1 - 11.4% and from 3.6-20%, respectively, at the expense of oleic acid, which decreased from 68.6-42.6% of total fatty acids. The glucosinolate contents increased from 12.4 micromol/g in the parental plant to 19 micromol/g DM in the GM-plant. Full-fat rapeseed of both cultivars was incorporated in pig diets at a level of 15%, and the digestibility and the production efficiency were tested under ad libitum feeding conditions with ten pigs each over the growing finishing period from 32-105 kg BW. The experimental diets did not show significant differences in digestibility and energetic feeding value. However, feed intake and weight gain decreased presumably due to the increasing glucosinolate intake associated with the feeding of transgenic rapeseed. The dietary fatty acids profile influenced the fatty acid profile of body fat. Myristic acid accumulated in back fat and intramuscular fat while the oleic acid content decreased. The increased glucosinolate intake affected the weight of thyroid glands and their iodine concentration.

Dealing with variability in food production chains: a tool to enhance the sensitivity of epidemiological studies on phytochemicals.

BACKGROUND: Many epidemiological studies have tried to associate the intake of certain food products with a reduced risk for certain diseases. Results of these studies are often ambiguous, conflicting, or show very large deviations of trends. Nevertheless, a clear and often reproduced inverse association is observed between total vegetable and fruit consumption and cancer risk. Examples of components that have been indicated to have a potential protective effect in food and vegetables include antioxidants, allium compounds and glucosinolates. AIM: The food production chain can give a considerable variation in the level of bioactive components in the products that are consumed. In this paper the effects of this variability in levels of phytochemicals in food products on the sensitivity of epidemiological studies are assessed. METHODS: Information on the effect of variation in different steps of the food production chain of Brassica vegetables on their glucosinolate content is used to estimate the distributions in the levels in the final product that is consumed. Monte Carlo simulations of an epidemiological cohort study with 30,000 people have been used to assess the likelihood of finding significant associations between food product intake and reduced cancer risk. RESULTS: By using the Monte Carlo simulation approach, it was shown that if information on the way of preparation of the products by the consumer was quantified, the statistical power of the study could at least be doubled. The statistical power could be increased by at least a factor of five if all variation of the food production chain could be accounted for. CONCLUSIONS: Variability in the level of protective components arising from the complete food production chain can be a major disturbing factor in the identification of associations between food intake and reduced risk for cancer. Monte Carlo simulation of the effect of the food production chain on epidemiological cohort studies has identified possible improvements in the set up of such studies. The actual effectiveness of food compounds already identified as cancer-protective by current imprecise methods is likely to be much greater than estimated at present.