55 research outputs found
Current Trends in Sample Treatment Techniques for Environmental and Food Analysis
Nowadays, there is a growing need for applications in food and environmental areas able to
cope with the analysis of a large number of analytes in very complex matrices [1]. The new
analytical procedures demand sensitivity, robustness, effectiveness and high resolution with
reduced analysis time. Many of these requirements may be met to a certain extent by the
total or partial automation of the conventional analytical methods, including sample
preparation or sample pre-treatment coupled on-line to the analytical system. Furthermore,
the recent use of ultra-high-performance liquid chromatography (UHPLC) for
environmental and food chemical analysis has increased the overall sample throughput and
laboratory efficiency without loss (and even with an improvement) of resolution obtained
by conventional HPLC systems..
Utjecaj dijetalnog ribljeg ulja na razinu n-3 polinezasićenih masnih kiselina, trans-kiselina i konjugirane linolne kiseline u ovčjem mlijeku
Three groups of ten lactating Sardinian ewes were used between 3rd and 6th month of lactation to determine the effects of supplementing diets with n-3 fatty acids on milk production and milk fat composition. The control group (A) was fed on a mixture of Gramineae hay with a pelleted alfalfa and concentrate; the other groups (B and C) were given the control ration supplemented with graded levels of fish oil. Milk content of nutritionally important fatty acids (n-3 polyunsaturated fatty acids, PUFA; trans acids and conjugated linoleic acid, CLA) was determined by gas chromatography. Unlike cow milk, milk of normally fed ewes contained detectable quantities of n-3 PUFA and higher amounts of CLA. The supplementation with fish oil resulted in an increased milk fat levels of n-3 PUFA, CLA and trans isomers. There was a positive correlation (R2 = 0.964) between the trans and n-3 fatty acid content in ewe milk, and a close positive correlation (R2 = 0.996) between CLA and trans monoenoic fatty acid contents. PUFA supplementation resulted in a slightly, but not statistically significative, decrease of milk fat percentage. On the contrary, dietary fish oil markedly affected milk production: ewes fed on the n-3 supplemented diet produced more milk than the ewes fed with the control diet.Izdvojene su tri skupine od po 10 ovaca sa Sardinije između 3. i 6. mjeseca laktacije kako bi se utvrdio utjecaj dodatne ishrane s n-3 masnim kiselinama na proizvodnju mlijeka i sastav masnoća u mlijeku. Kontrolna skupina (A) hranjena je smjesom sijena od Gramineae s kuglicama lucerne i koncentratom; ostale skupine (B i C) hranjene su kao i kontrolna, ali uz sve veću količinu ribljeg ulja. Plinskom kromatografijom određene su u mlijeku nutritivno važne masne kiseline (n-3 polinezasićene masne kiseline, PUFA; trans-kiseline i konjugirana linolna kiselina, CLA). Za razliku od kravljeg mlijeka, mlijeko normalno hranjenih ovaca sadržavalo je primjetne udjele n-3 PUFA i veće količine CLA. Dodatak ribljeg ulja očitovao se u povećanoj količini n-3 PUFA, CLA i trans-izomera u mliječnoj masti. U ovčjem mlijeku postoji pozitivna korelacija (R2 = 0,964) između količine trans- i n-3 masnih kiselina, a uska pozitivna korelacija (R2 = 0,996) između udjela CLA i trans-monoenskih masnih kiselina. Dodatak PUFA uzrokovao je slabo, ali statistički nesignifikantno, snizivanje postotka mliječne masti. Dijetalno riblje ulje značajno je utjecalo na proizvodnju mlijeka: ovce hranjene dodatnim n-3 masnim kiselinama proizvele su više mlijeka od onih koje su bile u kontrolnoj skupini
[The role of eggs in the diet: nutraceutical and epigenetic aspects].
The use of eggs in human diet has been object of many prejudices which are not yet completely disappeared The evolution of knowledge in the field of nutrition has, partially, countered these prejudices by highlighting the biological importance of several compounds present in the eggs. The nutritional and commercial revaluation of the eggs are passed through the enrichment of the lipid fraction in omega3 polyunsaturated fatty acids (PUFA omega3) which, have shown positive effects against cardiovascular diseases and development of the central nervous system and retina. The enrichment of eggs lipid with omega3 fatty acids is carried out by the integration of feeding hens with oils rich in omega3 fatty acids such as plant or marine oils. The results showed that the accumulation of omega3 in the egg yolk lipids is strongly affected by the type of oil used as supplement and by the amounts of oils administrated to the hens
Prunus persica var. platycarpa (Tabacchiera Peach): bioactive compounds and antioxidant activity of pulp, peel and seed ethanolic extracts
A comparative analysis of ethanol extracts from peel, pulp and seed of Prunus persica var. platycarpa (Tabacchiera peach) was done. The total phenols, flavonoids and carotenoids content as well as the antioxidant properties were evaluated. Peach pulp extract was characterized by the highest total phytonutrients content and exhibited the highest antioxidant activity in all in vitro assays. Interestingly, pulp extract showed IC50 values of 2.7 and 2.2 g/mL at 30 and 60 minutes of incubation, respectively using -carotene bleaching test. A remarkable result was also obtained by using Fe-chelating assay (IC50 of 2.9 g/mL vs 1.3 g/mL for positive control BHT). Pulp extract was subjected to liquid chromatography-electrospray-tandem mass spectrometry (HPLC-ESI-MS/MS). Six main compounds, namely gallic acid, protocatechuic acid, protocatechualdehyde, chlorogenic acid, p-coumaric acid, and ferulic acid, were identified. Overall, the results suggest that Prunus persica var. platycarpa displays a good antioxidant activity and its consumption could be promote
Evolution of phenolics and glutathione in Verdicchio wine obtained with maceration under reductive conditions
a b s t r a c t The aim of this study was to evaluate the influence of different skin contact percentage (0, 150 and 600 g L À1 of pomace), on the phenolic content and on the reduced glutathione levels in white Verdicchio musts and in the derived wines by using reductive conditions in an industrial winery. The results were compared with those from a control must obtained without maceration. The samples were taken after pressing, during alcoholic fermentation and after six months of storage. The skin contact in low-oxygen atmosphere lead to an increase of the phenolic content and glutathione in must and white wine. At the end of fermentation, the macerated samples with pomace at 600 g L À1 showed higher reduced glutathione and phenolic content, with respect to the other samples. Glutathione and tyrosol were positively correlated with yeast activity but then decreased during ageing. Ethyl caffeate increased in all samples during fermentation and wine ageing, thus confirming its origin as a condensation product between caffeic acid and ethanol after the hydrolysis of caftaric acid
Spent espresso coffee grounds as a source of anti-proliferative and antioxidant compounds
Disposal of spent espresso coffee grounds (SCG) is costly and leads to the loss of bioactive compounds that could be fractionated, in several applications. This work aimed to investigate phenolic profile, tocopherols, and antioxidant and anti-proliferative activities of SCGs ethanolic extracts from coffee powders differing in coffee provenience and composition (arabica/robusta). Tyrosol, detected for the first time in SCGs, was the most abundant phenolic measured (121-1,084 mg/kg in the extract), along with 4-hydroxybenzoic acid and vanillin (885-1813 and 340-1103 mg/kg, respectively). Extract derived from 100% robusta from Guatemala (S7-R) showed the highest α- to ß-tocopherol ratio of 1.2 and the highest antioxidant potential as evidenced by RACI and GAS values of -0.43 and 0.20, respectively. Moreover, S7-R showed a promising anti-proliferative activity toward human lung carcinoma cells (A549), with IC50 value of 61.2 ug/mL comparable to that given by the positive control vinblastine (IC50 value of 67.3 ug/mL)
Glucosinolates and polyphenols of colored Cauliflower as chemical discriminants based on cooking procedures
The impact of mild oven treatments (steaming or sous vide) and boiling at 10 min, 25 min, or 40 min on health-promoting phytochemicals of orange and violet cauliflower (Brassica oleracea L. var. botrytis) was investigated. For this purpose, targeted ultra-high performance liquid chro-matography-high resolution mass spectrometry analysis of phenolics and glycosylates com-bined with chemometrics was employed. Regardless of cooking time, clear differentiation of cooked samples obtained using different procedures was achieved, thus demonstrating the dis-tinct impact of cooking approaches on sample phytochemical profile (both, compound distribu-tion and content). The main responsible components for the observed discrimination were de-rivatives of hydroxycinnamic acid and kaempferol, organic acids, indolic and aromatic glucos-inolates, with glucosativin that was found, for the first time, as discriminant chemical descriptor in colored cauliflower submitted to steaming and sous-vide. The obtained findings also high-lighted a strict relationship between the impact of the cooking technique used and the type of cauliflower. The boiling process significantly affected phytochemicals in violet cauliflowers whereas orange cauliflower boiled samples were grouped between raw and either steamed or sous-vide cooked samples. Finally, the results confirm that the proposed methodology is capa-ble of discriminating cauliflower samples based on their phytochemical profiles and of identi-fying the cooking procedure able to preserve bioactive constituents
Is Coffee Powder Extract a Possible Functional Ingredient Useful in Food and Nutraceutical Industries?
The present study aimed to assess the phytochemical content and in vitro bioactivity of ethanolic extracts of Arabica (A) and/or Robusta (R) coffee powder having different geographical origins. For this purpose, total phenols (TPC) and flavonoids (TFC) content as well as a- and b-tocopherol were quantified. The antioxidant activity was assessed by using a multi-target approach in which the radical scavenging potential, the protection from lipid peroxidation, and the involvement of the iron-reducing mechanism were applied. The carbohydrate hydrolyzing enzymes' (a-amylase and a-glucosidase) inhibitory activities were also assessed. Arabica coffee sample (C2-A) showed the highest TPC, TFC, and a-tocopherol content with values of 63.1 mg chlorogenic acid equivalents (CAE)/g dry powder, 16.2 mg of quercetin (QE) equivalents/g dry powder, and 5.6 mg/100 g dry powder, respectively. Relative Antioxidant Capacity Index (RACI), used to statistically integrate results from 2,2′-azino-bis(3- ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing ability power (FRAP), and protection of lipid peroxidation assays, evidenced that sample C4-R derived from Robusta from Guatemala showed the highest antioxidant potential with a value of -0.61. Arabica from Puerto Rico was the most active against a-amylase, whereas the blend Arabica/Robusta sample (C5-A60R40) showed the highest inhibitory activity against a-glucosidase with IC50 values of 120.2 and 134.6 mg/mL, respectively. The results show how the qualitative-quantitative composition of the extracts is strongly associated not only with the variety but also with the geographical origin of the samples
Effects of the Fruit Ripening Stage on Antioxidant Capacity, Total Phenolics, and Polyphenolic Composition of Crude Palm Oil from Interspecific Hybrid Elaeis oleifera × Elaeis guineensis
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