Nutritive evaluation of the seed,germinated seed,and string bean of Erythrina americana and the detoxification of the material by boiling

The nutritive and toxicological values of the dry seeds, germinated seeds, and string beans of Erythrina americana were studied using raw and boiled samples. Raw germinated seeds had a higher protein content and lower fiber content than dry seeds. The whole string bean had lower protein content and higher fiber content. However, the seeds of the green pod showed the same protein concentration as the dry seeds (dry basis). Boiling and elimination of broth was beneficial in diminishing the alkaloid concentration in all the samples. The trypsin inhibitors, lectins, and tannins were also diminished as was expected. The raw string bean showed the lowest LD(50). Although the total essential amino acids content of the boiled germinated seeds was increased, the quality of protein, protein efficiency ratio (PER), was lower than in boiled dry seeds, and in these, the PER was similar to the control (casein). The present results suggest that for the protein quality and low alkaloid content, the boiled dry seeds and string beans could be used for animal feeding. It could be interesting to test the raw string beans in ruminants since in this stage E. americana showed the lowest toxicity.     

Ochratoxin A on green coffee: influence of harvest and drying processing procedures

Ochratoxin A is a metabolite produced by Aspergillus and Penicillium species that is nephrotoxic and possibly carcinogenic to humans. The aim of this study was to evaluate ochratoxin A contamination in green coffee obtained by different harvesting and drying operations and from fruits of different ripening stages in order to identify hazards. The research was directed to coffees from the highland area of Rio de Janeiro state (Brazil), which is traded in the domestic market. Twenty-two out of 54 samples contained ochratoxin A at levels ranging from 0.3 to 160 microg/kg. Ochatoxin A contamination levels between different ripe stage fruits were not significant (P > 0.05). "Varri??o" coffee, consisting of fruits that fell from the tree spontaneously and stayed longer on the ground before being harvested, was the most contaminated. Eleven out of 14 samples of varri??o coffee were contaminated. Three out of 10 samples from the northwestern region of the state were positive for ochratoxin at levels ranging from 10.1 to 592 microg/kg. The contaminated samples had in common the fact that they were harvested directly from the soil.     

Effects of roasting on hazelnut lipids

The effect of roasting on some nutritional characteristics of hazelnut lipidic fraction was investigated. Hazelnuts (Corylus avellana L.) were submitted to several different thermal treatments, comprising different temperatures (125-200 degrees C) and times of exposure (5, 15, and 30 min) and analyzed for their moisture and crude fat. Raw and roasted hazelnuts were also analyzed for their compositions in phytosterols and fatty acids (including trans isomers) by GC-FID, triacylglycerols by HPLC-ELSD, and tocopherols and tocotrienols by HPLC-DAD/fluorescence spectroscopy. Minor changes occurred in the fatty acid and triacylglycerol compositions. As temperatures and roasting periods increased, generally, a modest increase of oleic and saturated fatty acids and a decrease of linoleic acid, expressed as relative percentages, occurred. Similarly, an increase of triacylglycerols containing oleic acid moieties and a decrease of those containing linoleic acid moieties were found in the roasted samples. Roasting caused a modest decrease of the beneficial phytosterols (maximum 14.4%) and vitamin E homologues (maximum 10.0%) and a negligible increase of the trans fatty acids.     

Putative role of pith cell wall phenylpropanoids in Sesamia nonagrioides (Lepidoptera: Noctuidae) resistance

The stem borer Sesamia nonagrioides (Lefèbvre) is the most important insect pest that attacks maize, Zea mays L., in northwestern Spain. Host plant resistance to this borer was investigated in relation to the cell wall phenylpropanoids content in the pith. Eight inbred lines that differ in resistance were analyzed. Three major simple phenolic acids, p-coumaric, trans-ferulic, and cis-ferulic acids, and three isomers of diferulic acid, 8-5', 8-O-4', and 8-5'b (benzofuran form), were identified. The amount of all these compounds was correlated with the resistance level in the genotypes, with the resistant inbreds having the highest concentrations. The role of these compounds in cell wall fortification and lignification is well-documented, suggesting their possible intervention in S. nonagrioides resistance. Future studies that focus on these compounds could be useful to enhance S. nonagroides resistance.     

Ontogenic profiling of glucosinolates, flavonoids, and other secondary metabolites in Eruca sativa (salad rocket), Diplotaxis erucoides (wall rocket), Diplotaxis tenuifolia (wild rocket), and Bunias orientalis (Turkish rocket)

As an influence of the Mediterranean diet, rocket species such as Eruca sativa L., Diplotaxis species, and Bunias orientalis L. are eaten all over the world at different ontogenic stages in salads and soups. They are all species within the plant order Capparales (glucosinolate-containing species), and all are from the family Brassicaceae. Predominantly, the leaves of these species are eaten raw or cooked, although Eruca flowers are also consumed. There is considerable potential with raw plant material for a higher exposure to bioactive phytochemicals such as glucosinolates, their hydrolysis products, and also phenolics, flavonoids, and vitamins such as vitamin C. These compounds are susceptible to ontogenic variation, and the few published studies that have addressed this topic have been inconsistent. Thus, an ontogenic study was performed and all samples were analyzed using a previously developed robust liquid chromatography/mass spectrometry method for the identification and quantification of the major phytochemicals in all tissues of the rocket species. Seeds and roots of both Eruca and Diplotaxis contained predominantly 4-methylthiobutylglucosinolate. Leaves of Eruca and Diplotaxis contained high amounts of 4-mercaptobutylglucosinolate with lower levels of 4-methylthiobutlyglucosinolate and 4-methylsulfinylbutylglucosinolate. Flowers of Eruca and Diplotaxiscontained predominantly 4-methylsulfinylbutyl-glucosinolate. In addition, roots of both Diplotaxisspecies contained 4-hydroxybenzylglucosinolate but 4-hydroxybenzylglucosinolate was absent from roots of Eruca. Seeds and seedlings of all Eruca contained N-heterocyclic compounds but no sinapine, whereas Diplotaxis contained sinapine but not the N-heterocycles. In all tissues of B. orientalis, 4-hydroxybenzylglucosinolate and 4-methylsulfinyl-3-butenylglucosinolate were predominant. All rocket tissues, except roots, contained significant levels of polyglycosylated flavonoids, with/without hydroxycinnamoyl acylation. The core aglycones were kaempferol, quercetin, and isorhamnetin. The exception was B. orientalis, which had a negligible seed flavonoid content as compared with the other species. Anthocyanins were only detected in Eruca flowers and consisted of a complex pattern of at least 16 different anthocyanins.     

Lipophilic hydroxytyrosyl esters. Antioxidant activity in lipid matrices and biological systems

Antioxidant activities of lipophilic hydroxytyrosyl acetate, palmitate, oleate, and linoleate were compared with those of hydroxytyrosol, alpha-tocopherol, and butylhydroxytoluene (BHT) in both glyceridic matrix and biological systems. Aliquots of a glyceridic matrix spiked with various concentrations of antioxidant were subjected to accelerated oxidation in a Rancimat apparatus operated at 90 degrees C. The relationships between induction time (IT) and antioxidant concentration (mmol/kg) presented by hydroxytyrosol and hydroxytyrosyl acetate, palmitate, oleate, and linoleate were similar. Hydroxytyrosol and its esters showed greater antioxidant activity than alpha-tocopherol or BHT. We also evaluated the capacity of hydroxytyrosyl esters to protect proteins and lipids against oxidation caused by peroxyl radicals, using a brain homogenate as an ex vivo model. All tested compounds showed a protective effect in these systems, which was greater in preventing the generation of carbonyl groups in protein than of malondialdehyde in lipid. Inclusion of a lipophilic chain in the hydroxytyrosol molecule enhanced its antioxidant capacities in this biological model.     

Effect of industrial dehydration on the soluble carbohydrates and dietary fiber fractions in legumes

The effects of soaking, cooking, and industrial dehydration treatments on soluble carbohydrates, including raffinose family oligosaccharides (RFOs), and also on total dietary fiber (TDF), insoluble dietary fiber (IDF), and soluble (SDF) dietary fiber fractions were studied in legumes (lentil and chickpea). Ciceritol and stachyose were the main alpha-galactosides for chickpea and lentil, respectively. The processing involved a drastic reduction of soluble carbohydrates of these legumes, 85% in the case of lentil and 57% in the case of chickpea. The processed legume flours presented low residual levels of alpha-galactosides, which are advisable for people with digestive problems. Processing of legumes involved changes in dietary fiber fractions. A general increase of IDF (27-36%) due to the increase of glucose and Klason lignin was observed. However, a different behavior of SDF was exhibited during thermal dehydration, this fraction increasing in the case of chickpea (32%) and decreasing in the case of lentil (27%). This is probably caused by the different structures and compositions of the cell wall networks of the legumes.     

Real-time TaqMan polymerase chain reaction detection and quantification of cow DNA in pure water buffalo mozzarella cheese: method validation and its application on commercial samples

Mozzarella cheese obtained from buffalo (Bubalus bubalis) milk is a typical Italian product certificated by means of the European Protected Designation of Origin (PDO). Mozzarella cheese can also be obtained from bovine milk or bovine/buffalo milk mixtures, but in this case, it cannot be sold as PDO product, and its label must report the actual ingredients. However, bovine milk in PDO products was frequently detected in the past, suggesting fraudulent addition or accidental contamination. Several methods based on end-point polymerase chain reaction (PCR) have been profitably applied in a large number of tests to detect the presence of undeclared ingredients, also in dairy products. In the present study we report a real-time PCR method able to quantify bovine milk addition to pure buffalo cheese products. We validated a normalized procedure based on two targets: bovine mitochondrial cytochrome b (cyt b) to detect and quantify the bovine DNA and nuclear growth hormone (GH) gene used as a universal reference marker. With the use of this real-time PCR assay, 64 commercial mozzarella di bufala cheese samples purchased at local supermarkets, dairy shops, or directly from cheese manufacturers were analyzed. The results obtained demonstrate that most of the commercial samples were contaminated with bovine milk. Therefore, this assay could be conveniently employed to carry out routine and accurate controls aimed not only to discourage any fraudulent behavior but also to reduce risks for consumer health.     

Primary and secondary metabolite composition of kernels from three cultivars of Portuguese chestnut (Castanea sativa Mill.) at different stages of industrial transformation

Chestnut (Castanea sativa) is an important basic food in rural diets and a major starch crop used in a similar way to potatoes. Chestnuts are a fundamental economic resource in the "chestnut regions" not only for the fruit but also for the chestnut wood. Chestnuts have become increasingly important with respect to human health, for example, as an alternative gluten-free flour source. Chestnuts are also a rich source of other beneficial compounds, but there have been few studies on the composition during processing. In this study, we analyzed the chemical composition of three Portuguese cultivars at different stages of industrial processing. The chestnut cultivars were Longal, Judia, and Martaínha. All three cultivars had high moisture contents but were low in ash, crude fat, and crude protein contents, with high starch and low fiber contents. The free amino acid contents, including various essential amino acids, varied depending on the cultivar. All three cultivars also had a significant content of polyphenolics with gallic acid; ellagic acid was predominant among hydrolyzable and condensed tannins. Many of these compounds are known to exert significant positive effects on human health. The one-way analysis of variance for fresh chestnut shows significant differences among the three cultivars for most of the studied parameters. The same statistical analysis applied to each one of the two cultivars (Judia and Longal) sampled for the four processing steps analyzed indicates a significant effect of this factor in practically all of the constituents. On the other hand, the two-way analysis of variance shows that, besides the residual, the processing step and the interaction cultivar x processing step were the factors that more contributed for the total variation observed in the constituents analyzed, while the contribution of cultivar was much less significant.