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101.
Ulyana Angel Carla Manuela Silva Artur Cavaco-Paulo Aharon Gedanken 《Israel journal of chemistry》2010,50(4):524-529
The application of a rapid, non-destructive, cost-effective technique such as ultrasonic emulsification for the coating of different textiles was explored. The technical benefits for this research were the generation of multifunctional materials and their combinations through environmentally friendly processing technologies. We have shown for the first time that ultrasonic waves can be used to coat proteinaceous micro- and nanospheres (PM) of BSA (Bovine Serum Albumin) protein and casein on the surface of cotton and polyester (PE) fabrics. The creation and the anchoring of the microbubbles to the fabrics were performed by a one-step reaction, and the process is usually stopped after 3 min. The PM of bovine serum albumin (BSA) bonded to cotton and polyester fabrics has shown stability for ∼9 months. The PMs were shown to be attached more strongly to the polyester than to the cotton, and sustained stronger washing conditions on PE. The diameter of the BSA and the casein spheres on cotton was in the range of 0.8–1.0 μm, while on the PE it varied between 60 and 120 nm. 相似文献
102.
Steroid bioconversion: Towards green processes 总被引:1,自引:0,他引:1
Marco P.C. Marques Filipe Carvalho Carla C.C.R. de Carvalho Joaquim M.S. Cabral Pedro Fernandes 《Food and Bioproducts Processing》2010,88(1):12-20
There is an increasing trend towards reducing the use of organic solvents in industry due to environmental constraints and the adoption of green chemistry guidelines. To overcome the low volumetric productivity of aqueous bioconversion systems involving sparingly water soluble hydrophobic compounds, processes are being developed and designed to incorporate green solvent such as supercritical fluids, ionic liquids and natural oils, and liquid polymers, among others as an alternative to organic solvents. Moreover, processes are developed and redesigned to use/reuse chemicals and reagents derived from waste or renewable feed stocks in order to diminish E-factors.In this work, the use of green solvents as key components in the bioconversion media for a multi-step microbial bioconversion was assessed in a suspended whole cell system, combined with the use of by-products as raw materials, ultimately used as carbon source for cell growth and as sterol substrate for bioconversion. The model system is the selective cleavage of the side-chain of β-sitosterol performed by free resting cells of Mycobacterium sp. NRRL B-3805, a well-established industrial multi-enzymatic process involving the use of nine catabolic enzymes in a 14-step metabolic pathway.Bioconversion yields in silicone media were higher than the ones obtained in polyethylene glycol (PEG), polypropylene glycol (PPG) and ionic liquids, as well as in dioctyl phthalate (DOP), an organic solvent that has previously been shown to allow high conversion yields. Total conversion of 12 mM substrate in silicone media was consistently obtained at the end of 120-h bioconversion runs. Similar bioconversion profiles were attained during a 50-fold scale-up, maintaining constant the power consumption per unit of volume. 相似文献
103.
Débora Ravelli Carla Romero Matsuoka Regina Célia Della Modesta Thais Maria Ferreira de Souza Vieira Marisa Aparecida Bismara Regitano-d’Arce 《Journal of the American Oil Chemists' Society》2010,87(5):515-520
Measurements of degradation in frying oils are mainly based on physico-chemical properties. Total polar compounds (TPC) and
free fatty acids (FFA) content in frying oils are used as a guide for discarding used oils. The purpose of this study was
to evaluate the efficacy of a sensory method in detecting degradation in soybean oils used in potato chips deep frying. The
sensory evaluation of oil samples was determined by a trained panel; after rigorous selection and training steps. Free fatty
acid, TPC and Rancimat induction period (IP) were quantified in the same samples. The proposed sensory method was sensitive
to small differences in rancidity. The selected and trained sensory panel discarded oil samples with 0.175% FFA as oleic acid,
18.92% TPC, and 0.20 h IP. According to the results achieved in this research sensorial trained panel response is sensitive
and accurate in refusing deteriorated frying oils. Besides this, soybean oil can be used for deep frying procedures and safely
discarded according to the panel response, although presenting up to 7% linolenic acid. 相似文献
104.
Bazzicalupi C Chioccioli M Sissi C Porcù E Bonaccini C Pivetta C Bencini A Giorgi C Valtancoli B Melani F Gratteri P 《ChemMedChem》2010,5(12):1995-2005
Three novel 2,7-substituted acridine derivatives were designed and synthesized to investigate the effect of this functionalization on their interaction with double-stranded and G-quadruplex DNA. Detailed investigations of their ability to bind both forms of DNA were carried out by using spectrophotometric, electrophoretic, and computational approaches. The ligands in this study are characterized by an open-chain (L1) or a macrocyclic (L2, L3) framework. The aliphatic amine groups in the macrocycles are joined by ethylene (L2) or propylene chains (L3). L1 behaved similarly to the lead compound m-AMSA, efficiently intercalating into dsDNA, but stabilizing G-quadruplex structures poorly, probably due to the modest stabilization effect exerted by its protonated polyamine chains. L2 and L3, containing small polyamine macrocyclic frameworks, are known to adopt a rather bent and rigid conformation; thus they are generally expected to be sterically impeded from recognizing dsDNA according to an intercalative binding mode. This was confirmed to be true for L3. Nevertheless, we show that L2 can give rise to efficient π-π and H-bonding interactions with dsDNA. Additionally, stacking interactions allowed L2 to stabilize the G-quadruplex structure: using the human telomeric sequence, we observed the preferential induction of tetrameric G-quadruplex forms. Thus, the presence of short ethylene spacers seems to be essential for obtaining a correct match between the binding sites of L2 and the nucleobases on both DNA forms investigated. Furthermore, current modeling methodologies, including docking and MD simulations and free energy calculations, provide structural evidence of an interaction mode for L2 that is different from that of L3; this could explain the unusual stabilizing ability of the ligands (L2>L3>L1) toward G-quadruplex that was observed in this study. 相似文献
105.
Aquilanti L Garofalo C Osimani A Silvestri G Vignaroli C Clementi F 《Journal of food protection》2007,70(3):557-565
The transfer via the food chain from animals to humans of microbes that are resistant to antimicrobial agents is of increasing concern. To determine the contributions of nonpathogenic microflora to the occurrence and spread of antibiotic resistance (AR) genes in the food chain, 123 lactic acid bacteria were isolated from 29 samples of raw and processed pork and chicken meat products that had previously tested positive for one or more AR genes that encode clinically relevant ARs: tet(M), tet(O), tet(K), erm(A), erm(B), erm(C), aac (6')-Ie aph (2")-Ia, mecA, and blaZ. All of the isolates were initially tested for their AR gene profiles by PCR. The 59 isolates carrying a tet, erm, or blaZ gene were taken through molecular identification, analyzed by determination of the MIC, and subjected to genetic fingerprinting. Lactococcus garvieae was the predominant species (28 isolates), followed by Lactobacillus plantarum (11 isolates) and L. salivarius (6 isolates), whereas Lactococcus lactis subsp. lactis, Lactobacillus johnsonii, L. reuteri, L. crispatus, and L. brevis were identified at lower frequencies. The tet(M) and erm(B) genes were the most frequently detected. Assessment of multiple resistances in 18 tet positive (tet+) isolates revealed that tet(M) plus erm(B) and tet(K) plus erm(B) were the most frequent AR gene patterns. Partial sequencing of the tet(M) open reading frame of three selected strains showed high sequence similarities (> 99%) with tet(M) genes previously found in human pathogens (Listeria monocytogenes and Neisseria meningitidis). Southern hybridization with plasmid profiles revealed these strains contained tet(M)-carrying plasmids. 相似文献
106.
Carla Pereira Lillian Barros Ana Maria Carvalho Isabel C.F.R. Ferreira 《Food research international (Ottawa, Ont.)》2011,44(9):2634-2640
Beyond the composition of the usual macronutrients and micronutrients, it is important to provide information on the composition of bioactive compounds and antioxidant capacity of foods, particularly of wild species to regain them for nowadays' dietary habits. Many greens are known as excellent sources of natural antioxidants, and consumption of fresh plants in the diet may contribute to the daily antioxidant intake. In the present study five leafy wild greens traditionally consumed (Borago officinalis, Montia fontana, Rorippa nasturtium-aquaticum, Rumex acetosella, Rumex induratus) were studied in order to document macronutrient, micronutrient and non-nutrient composition. R. induratus revealed the highest levels of sugars, ascorbic acid, tocopherols, lycopene, chlorophylls, flavonoids, and one of the highest antioxidant activity expressed as DPPH scavenging activity, β-carotene bleaching inhibition, and TBARS formation inhibition. R. nasturtium-aquaticum showed the healthier PUFA/SFA and n-6/n-3 ratios, and B. officinalis proved to be a source of γ-linolenic acid and other fatty acids from n-6 series that are precursors of mediators of the inflammatory response. The nutritional characteristics and antioxidant potential of these wild greens require reconsideration of their role in traditional as well as in contemporary diets. Furthermore, their extracts might find applications in the prevention of free radical-related diseases, as functional food formulations. 相似文献
107.
Mercedes Aleman Carla Daniela Nuchi Ricard Bou Alba Tres Javier Polo Francesc Guardiola Rafael Codony 《European Journal of Lipid Science and Technology》2010,112(7):761-769
Bakery products such as biscuits, cookies, and pastries represent a good medium for iron fortification in food products, since they are consumed by a large proportion of the population at risk of developing iron deficiency anemia, mainly children. The drawback, however, is that iron fortification can promote oxidation. To assess the extent of this, palm oil added with heme iron and different antioxidants was used as a model for evaluating the oxidative stability of some bakery products, such as baked goods containing chocolate. The palm oil samples were heated at 220°C for 10 min to mimic the conditions found during a typical baking processing. The selected antioxidants were a free radical scavenger (tocopherol extract (TE), 0 and 500 mg/kg), an oxygen scavenger (ascorbyl palmitate (AP), 0 and 500 mg/kg), and a chelating agent (citric acid (CA), 0 and 300 mg/kg). These antioxidants were combined using a factorial design and were compared to a control sample, which was not supplemented with antioxidants. Primary (peroxide value and lipid hydroperoxide content) and secondary oxidation parameters (p‐anisidine value, p‐AnV) were monitored over a period of 200 days in storage at room temperature. The combination of AP and CA was the most effective treatment in delaying the onset of oxidation. TE was not effective in preventing oxidation. The p‐AnV did not increase during the storage period, indicating that this oxidation marker was not suitable for monitoring oxidation in this model. 相似文献
108.
109.
Isolation of red wine components with anti-adhesion and anti-biofilm activity against Streptococcus mutans 总被引:1,自引:0,他引:1
Maria Daglia Monica Stauder Adele Papetti Caterina Signoretto Giovanni Giusto Pietro Canepari Carla Pruzzo Gabriella Gazzani 《Food chemistry》2010
Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivoS. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated. 相似文献
110.
Carla Da Porto Deborha Decorti Franco Tubaro 《International Journal of Food Science & Technology》2011,46(5):988-993
Some Dominican ‘heavy’ rums, of a single brand, available commercially and labelled as 8, 15, 18, 21 and 25 year‐old have been evaluated and compared. Headspace solid‐phase microextraction (HS‐SPME) coupled to gas chromatography–mass spectrometry (GC–MS) was used to analyse volatile compounds and crocin kinetic competition test to evaluate their antioxidant capacity. The alcohols and esters profiles of rums labelled as 21‐ and 25 year‐old were similar. The alcohols and fatty acids profiles of rums labelled as 15 and 18 year‐old were similar. The esters profile of rums labelled as 8 and 15 year‐old was similar. Significant differences were found for aldehydes and volatile phenols between all the rum samples. The antioxidant capacity resulted significantly higher in the older rums (21 and 25 year‐old) than in the younger ones (8, 15 and 18 year‐old). 相似文献