1,721,099 research outputs found
The evolution of analytical chemistry methods in foodomics
No full textThe methodologies of food analysis have greatly evolved over the past 100 years, from basic assays based on solution chemistry to those relying on the modern instrumental platforms. Today, the development and optimization of integrated analytical approaches based on different techniques to study at molecular level the chemical composition of a food may allow to define a ‘food fingerprint’, valuable to assess nutritional value, safety and quality, authenticity and security of foods. This comprehensive strategy, defined foodomics, includes emerging work areas such as food chemistry, phytochemistry, advanced analytical techniques, biosensors and bioinformatics.
Integrated approaches can help to elucidate some critical issues in food analysis, but also to face the new challenges of a globalized world: security, sustainability and food productions in response to environmental world-wide changes. They include the development of powerful analytical methods to ensure the origin and quality of food, as well as the discovery of biomarkers to identify potential food safety problems. In the area of nutrition, the future challenge is to identify, through specific biomarkers, individual peculiarities that allow early diagnosis and then a personalized prognosis and diet for patients with food-related disorders.
Far from the aim of an exhaustive review of the abundant literature dedicated to the applications of omic sciences in food analysis, we will explore how classical approaches, such as those used in chemistry and biochemistry, have evolved to intersect with the new omics technologies to produce a progress in our understanding of the complexity of foods. Perhaps most importantly, a key objective of the review will be to explore the development of simple and robust methods for a fully applied use of omics data in food science
Comparison Between 2 Methods of Solid-Liquid Extraction for the Production ofCinchona calisayaElixir: An Experimental Kinetics and Numerical Modeling Approach
No full textThe purpose of this study is to compare the extraction process for the production of China elixir starting from
the same vegetable mixture, as performed by conventional maceration or a cyclically pressurized extraction process (rapid
solid–liquid dynamic extraction) using the Naviglio Extractor. Dry residue was used as a marker for the kinetics of the
extraction process because it was proportional to the amount of active principles extracted and, therefore, to their total
concentration in the solution. UV spectra of the hydroalcoholic extracts allowed for the identification of the predominant
chemical species in the extracts, while the organoleptic tests carried out on the final product provided an indication of
the acceptance of the beverage and highlighted features that were not detectable by instrumental analytical techniques.
In addition, a numerical simulation of the process has been performed, obtaining useful information about the timing of
the process (time history) as well as its mathematical description
Extraction and characterization of free non-polar lipid fraction of chocolate using a rapid analytical procedure.
Full text linkIn this work has been developed a new analytical procedure to extract the non-polar component of the lipid fraction of the chocolate, in a simple, rapid and economical way and its subsequent analysis by using a gas chromatograph equipped with flame ionization detector (GC-FID). The interest to isolate the non-polar lipid fraction containing triglycerides, waxes, sterol esters and minor components, such as sterols and liposoluble vitamins from the polar fraction could be of three types: analytical, nutritional and commercial. In analytical scope, the quality parameters of the lipid component of chocolate concern the non-polar component. Moreover, the chemical-physical parameters such as the melting point, refractive index, color, etc. were relative to a mixture of fatty substances was not well defined. From the nutritional point of view, the non-polar lipid fraction is the one that gives the largest contribution to the calorific value of the chocolate and then the separation of the two fractions could be useful to better assess the total caloric intake. For economic reasons, not the least important was considering the possibility of fraudulent additions of polar lipid components to replace the non-polar component more valuable, this alteration was not detectable only by applying the official method. The results obtained by the proposed procedure, combined with those obtained with the official method allowed to obtain more complete information on the composition of the lipid component of chocolate. Consequently, the ultimate goal could be reported this information on the nutrition labels of chocolate, for greater product transparency and greater consumer protection
EXTRACTION OF BIOACTIVE COMPOUNDS OF SAFFRON (CROCUS SATIVUS L.) BY ULTRASOUND ASSISTED EXTRACTION (UAE) AND BY RAPID SOLID-LIQUID DYNAMIC EXTRACTION (RSLDE)
Full text linkCrocus sativus L.(Iridaceae), commonly known as saffron is not only used as a spice in food, but also for its medicinal properties. For these reasons, in this study the comparison between a conventional extraction technique using ultrasounds (UAE) and a cyclically pressurized solid-liquid extraction with the Naviglio extractor (NE) or Rapid Solid- Liquid Dynamic Extraction (RSLDE) was performed, in order to obtain qualitative and quantitative data related to bioactive compounds of saffron. The extracts
obtained were analyzed for their antioxidant activity using ABTS, DPPH and
FRAP assays, for their total polyphenol content (Folin-Ciocalteu) and for the
metabolic profile using liquid chromatography coupled to tandem mass
spectrometry (LC/MS/MS).The efficiency of extraction of active principles
obtained with the Naviglio extractor was about four times higher than that
resulting from the sonication extraction. The results obtained showed that the extracts of the Naviglio extractor had significant advantages in terms of
extraction efficiency and quality of extract; moreover savings of time and
therefore represented an important data in anticipation of the use of such
extracts for the preparation of functional food and also phytodrugs
Antioxidant addition to prevent lipid and protein oxidation in chicken meat mixed with supercritical extracts of Echinacea angustifolia
No full textLipid and protein oxidation is a major phenomenon reducing meat quality during cooking and storage and leading to off-flavour formation and rancidity. The use of vegetable extracts to increase shelf life is a promising new frontier in the prevention of oxidation. In this study the efficacy on lipid and protein oxidation was evaluated in chicken meat mixed with conventional methanol/water and supercritical extracts of Echinacea angustifolia after cooking and at different times of cold storage in order to propose these matrices as natural substances to increase the shelf-life of meat products. Echinacea spp. are native to North America and were traditionally used by the Indian tribes for a variety of diseases, including mouth sores, colds and snakebites. The three most commonly used Echinacea spp. are Echinacea angustifolia, Echinacea pallida and Echinacea purpurea. In particular, a series of experiments have shown that E. angustifolia extracts have significant immunomodulatory activities. Total phenols and antioxidant activity of the SFE extracts were used as parameters to characterize the vegetable extracts, TBARS and MDA were considered to monitor lipid oxidation, while protein oxidation was measured as carbonyl compounds. Results show a protective action of plant antioxidants against oxidation, but also a greater selectivity and a higher efficiency of natural extracts obtained by SFE respect to conventional extract. The study of the metabolic profile was performed by tandem mass spectrometry (LC/MS/MS)
Omic Analysis of Protein and Peptide Toxins in Food
No full textFood products can be contaminated by toxic proteins and peptides derived from many different flources at any stage of the production chain. Food contamination represents a major public health concern, and for this reason, monitoring of food production has become crucial for preventing food poisfining. Proteomic-based methods constitute powerful tools for qualitative and quantitative determination of toxins in both raw ingredients and processed food matrices. This chapter presents an overview of the most common protein and peptide toxins contaminating food and critically describes the advanced proteomic approaches developed for their detection and control
Organization of a Sulfolobus solfataricus gene cluster homologous to the Escherichia coli str operon
No full textThe Sulfolobus solfataricus S12, S7 and S10 ribosomal proteins and the elongation factor 1 alphagenes are organized in a sequence analogous to that in the Escherichia coli str operon. Northern analysis showed that the S12 gene belongs to a transcript different from that corresponding to the other three genes. Compared to the Sulfolobus acidocaldarius S12 and to the Methanococcus vannielii S7 proteins, the S. solfataricus S12 and S7 proteins were 33 and 47 amino acids longer respectively. These differences were eliminated if the 5' flanking regions of the S. acidocaldarius S12 and the M. vannielii S7 genes were translated from a different start codon. Despite the structural similarities between the archaeal and the bacterial str operons the S. solfataricus ribosomal proteins S12, S7 and S10 are more similar to the eukaryotic counterparts
Study of the effects of a diet supplemented with active components on lipid and glycaemic profiles
No full textObjectives
Currently, there are numerous studies on risk factors for cardiovascular disease and the potential for functional foods to bring benefits or improve people's health. However, most of these studies are conducted with middle-aged individuals. The aim of this study was to evaluate the effects of supplementing a typical diet with some functional components, which are substances that when consumed in small quantities can improve people's welfare.
Methods
The participants in this study were young; slightly overweight; had normal glucose tolerance; and had lipid values indicating dyslipidemia or close dyslipidemia. Following a 4-wk run-in phase, participants followed either a diet containing foods enriched with ω-3 fatty acids, β-glucans, phytosterols, and vitamin E or an isoenergetic diet without the active components. Sixteen individuals (age range 20 to 37 y) were randomly assigned to one of two groups. At the end of treatment, while fasting, plasma concentrations of triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total cholesterol were measured. Furthermore, blood glucose was evaluated after fasting and after a meal enriched with β-glucans.
Results
There was a statistically significant reduction (α < 0.05) across the lipid profile. A meal rich in β-glucans produced a glycemic response significantly lower than the nonenriched meal.
Conclusion
The dietary supplements used in this work, based on the integration of functional components into the usual diet of the population, have proved effective in reducing peak levels of postprandial glucose and the risk for dyslipidemia. Therefore, these functional components proved a valuable aid in the prevention of cardiovascular diseases and metabolic disorders
Nucleotide sequence and molecular evolution of the gene coding for glyceraldehyde-3-phosphate dehydrogenase in the thermoacidophilic archaebacterium Sulfolobus solfataricus
No full textA Sulfolobus solfataricus genomic library cloned in the EMBL3 phage was screened using as probes synthetic oligonucleotides designed from the known amino acid sequence of a peptide obtained from the purified glyceraldehyde-3-phosphate dehydrogenase (aGAPD) protein. The screening led to the isolation of six recombinant phages (λG1–λG6) and one of them (λG4) contained the entire GAPD gene. The deduced amino acid sequence accounts for a protein made of 341 amino acids and the initial methionine is encoded by a GTG triplet. Alignment of the S. solfataricus aGAPD sequence versus GAPD from archaea, eukarya, and bacteria showed that a GAPD is very similar to other archaebacterial but not to eukaryotic or eubacterial GAPD. For known archaebacterial GAPD sequences, the rate of nucleotide substitutions per site per year showed that these sequences are homologous not only at the amino acid but also at the nucleotide level. The evolutionary rates are nearly similar to those reported for other eukaryotic genes
Microwave Assisted extraction of Phenolic Compounds of Four Different Spices
No full textSpices and herbs are known not only for their taste, aroma and flavour, but also for their medical properties and value. Both spices and herbs have been used for centuries in traditional medical systems to cure various kinds of illnesses such as common cold, diabetes, cough and cancers. The aim of this work was the comparison between two different extractive techniques in order to get qualitative and quantitative data regarding bioactive compounds of four different spices (Cinnamomum zeylanicum, Coriandrum sativum, Cuminum cyminum, Crocus sativus). The plants were extracted employing ultrasonication and microwave-assisted extractions. The efficiency of extraction of bioactive compounds obtained with the microwave extraction process was in general about four times higher than that resulting from sonication extraction. The various extracts obtained were analyzed for their antioxidant activity using ABTS, DPPH and FRAP assays and for their total polyphenolic content. It can be concluded that microwave-assisted extractions provide significant advantages in terms of extraction efficiency and time savings
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