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91.
Pullulan‐based films and coatings for food packaging: Present applications,emerging opportunities,and future challenges
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Stefano Farris Ilke Uysal Unalan Laura Introzzi José Maria Fuentes‐Alventosa Carlo A. Cozzolino 《应用聚合物科学杂志》2014,131(13)
Societal and industrial demands for lower environmental impact, cost effectiveness, and high‐performance goods and services are increasingly impacting the choice of technologies which are developed and deployed in consumer products. Like many other sectors, food packaging is moving to new technologies; the use of biopolymers is one of the most promising strategies toward an optimized use of traditional packaging materials (e.g., oil‐based plastics) without impairing the goal of extending shelf life. Among other food packaging materials, pullulan is attracting much attention due to its unique features. The goal of this review is to provide an overview of current and emerging applications of pullulan within the food packaging sector. In particular, the functional properties of interest for the food packaging industry will be discussed in light of the physicochemical attributes of this exopolysaccharide. Future challenges that may dictate the successful penetration of pullulan in the food packaging market are also outlined. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40539. 相似文献
92.
The results of thermally stimulated discharging currents and isothermal direct currents measurements, performed on crosslinked polyethylene cable models aged under different thermal and electrothermal stresses, are presented and discussed. It is shown that aging affects the low-frequency behavior of the polymer. The changes observed in the relaxation processes are related to those of other properties, e.g., density, melting enthalpy, electric strength, electrical conductivity, and microstructure, as well as to the degradation phenomena caused in the insulation by the applied stresses. The proposed techniques, therefore, prove to be an effective diagnostic tool for investigating the aging of polymeric insulating materials. © 1996 John Wiley & Sons, Inc. 相似文献
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Biagio Barone Luigi Napolitano Marco Abate Luigi Cirillo Pasquale Reccia Francesco Passaro Carmine Turco Simone Morra Francesco Mastrangelo Antonio Scarpato Ugo Amicuzi Vincenzo Morgera Lorenzo Romano Francesco Paolo Calace Savio Domenico Pandolfo Luigi De Luca Achille Aveta Enrico Sicignano Massimiliano Trivellato Gianluca Spena Carlo DAlterio Giovanni Maria Fusco Raffaele Vitale Davide Arcaniolo Felice Crocetto 《International journal of molecular sciences》2022,23(7)
Testosterone is the most important hormone in male health. Aging is characterized by testosterone deficiency due to decreasing testosterone levels associated with low testicular production, genetic factors, adiposity, and illness. Low testosterone levels in men are associated with sexual dysfunction (low sexual desire, erectile dysfunction), reduced skeletal muscle mass and strength, decreased bone mineral density, increased cardiovascular risk and alterations of the glycometabolic profile. Testosterone replacement therapy (TRT) shows several therapeutic effects while maintaining a good safety profile in hypogonadal men. TRT restores normal levels of serum testosterone in men, increasing libido and energy level and producing beneficial effects on bone density, strength and muscle as well as yielding cardioprotective effects. Nevertheless, TRT could be contraindicated in men with untreated prostate cancer, although poor findings are reported in the literature. In addition, different potential side effects, such as polycythemia, cardiac events and obstructive sleep apnea, should be monitored. The aim of our review is to provide an updated background regarding the pros and cons of TRT, evaluating its role and its clinical applicability in different domains. 相似文献
96.
Effect of sourdough fermentation on stabilisation,and chemical and nutritional characteristics of wheat germ 总被引:4,自引:0,他引:4
Carlo Giuseppe Rizzello Luana NionelliRossana Coda Maria De AngelisMarco Gobbetti 《Food chemistry》2010
Lactic acid bacteria strains were identified from wheat germ by 16S rRNA partial sequencing, subjected to RAPD-PCR typing and screened. Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5 were used as starters to produce sourdough fermented wheat germ (SFWG). The chemical and nutritional characteristics of SFWG were compared to those of the raw wheat germ (RWG). Lipase activity in SFWG was ca. 2.6-fold lower than that found in RWG. As shown by SPME/GC/MS analysis, most of the volatile compounds derived from lipid oxidation during storage (40 days) were at markedly lower levels in SFWG compared to RWG. Fermentation of wheat germ increased of ca. 50% the concentration of free amino acids. Glu markedly decreased in SFWG, due to its conversion in GABA. The concentration of the anti-nutritional factor raffinose also decreased in SFWG. The in vitro protein digestibility, the concentration of total phenols, phytase and antioxidant activities were increased by fermentation. 相似文献
97.
Alessandra Bosutti Barbara Dapas Gabriele Grassi Rossana Bussani Fabrizio Zanconati Fabiola Giudici Cristina Bottin Nicola Pavan Carlo Trombetta Bruna Scaggiante 《International journal of molecular sciences》2022,23(8)
Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer. 相似文献
98.
Carlo Ricciardi Giancarlo Canavese Riccardo Castagna Gabriella Digregorio Ivan Ferrante Simone L. Marasso Alessandro Ricci Valentina Alessandria Kalliopi Rantsiou Luca S. Cocolin 《Food and Bioprocess Technology》2010,3(6):956-960
The micro- and nano-technologies coupled with a deep knowledge of organic/inorganic interfaces guarantee an exceptional sensitivity
and specificity of the sensor, while the lab-on-a-chip platform reduces assay times and limits sampling and/or sample preparation,
providing compact and portable objects. Therefore, the development of innovative biosensors such as antibody-immobilized microcantilevers
can overcome the evident limits of nowadays technologies, such as time consuming, expensiveness, difficult automation, low
sensitivity, accuracy, and precision for quantitative methods. The present study proposes two device designs for the detection
of food pathogens, exploiting an antibody-immobilized microcantilever biosensors, a novel class of mass detectors. For the
first one, we integrated the mechanical sensors on a microfluidic platform (lab-on-a-chip) to perform online analysis, directly
in liquid environment. We showed that our portable biosensors could easily detect the presence of pathogenic bacteria such
as Salmonella enterica serotype enteritidis in concentration 105 cfu/mL in just 40 min, without any enrichment and/or sample preparation. To increase the mass sensitivity of our analysis,
we also fabricated microstructures optimized for vibrating in vacuum environment. Using a dip-and-dry technique, we showed
that, in such configuration, the experimental limit of detection is as low as 103 cfu/mL. Due to the extremely small volumes needed, our biosensors operating in vacuum have the potentiality of detecting
the presence or absence of a single cell. 相似文献
99.
Giacomo Luigi Petretto Carlo Ignazio Giovanni Tuberoso Maurizio Antonio Fenu Jonathan P. Rourke Omar Belhaj Giorgio Pintore 《International Journal of Food Properties》2017,20(9):2016-2027
The bioprospecting of several monofloral Moroccan honeys was carried out. The antiradical activity expressed as mmol Trolox equivalents/kg of honey and evaluated by 2,2-diphenyl-1-picrylhydrazyl assay, ranged from 0.15 for euphorb honey to 1.08 for citrus honey. The antioxidant activity expressed as mmol Fe2+/kg and evaluated by ferric ion reducing antioxidant power assay, ranged from 0.96 for euphorb honey to 4.74 for orange honey. The total phenol content was evaluated by colorimetric assay, while the color attributes were evaluated as transmittance data. Significant Pearson correlation factors were found between total polyphenol amount and antioxidant activity and between color attributes and antioxidant activity. Furthermore the chemical composition of volatile organic compounds was determined. The volatile organic compounds chemical composition of the studied honeys was mainly represented by terpene and benzene derivatives, Maillard reaction products, isoprenoids, and hydrocarbons. The volatiles fingerprint, as well as a targeted high-performance liquid chromatography analysis of the polar components, was used to tentatively confirm the declared botanical origin of the samples studied. 相似文献
100.
Potent,Metabolically Stable 2‐Alkyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐adenines as Adenosine A2A Receptor Ligands
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Dr. Silvia Pace Dr. Giandomenico Brogin Dr. Maria Antonietta Stasi Dr. Teresa Riccioni Franco Borsini Dr. Francesca Capocasa Dr. Francesco Manera Carlo Tallarico Dr. Pietro Grossi Dr. Federica Vacondio Dr. Michele Bassi Dr. Francesca Bartoccini Dr. Simone Lucarini Dr. Giovanni Piersanti Prof. Giorgio Tarzia Walter Cabri Dr. Patrizia Minetti 《ChemMedChem》2015,10(7):1149-1152
Inhibition of adenosine A2A receptors has been shown to elicit a therapeutic response in preclinical animal models of Parkinson’s disease (PD). We previously identified the triazolo‐9H‐purine, ST1535, as a potent A2AR antagonist. Studies revealed that ST1535 is extensively hydroxylated at the ω‐1 position of the butyl side chain. Here, we describe the synthesis and evaluation of derivatives in which the ω‐1 position has been substituted (F, Me, OH) in order to block metabolism. The stability of the compounds was evaluated in human liver microsomes (HLM), and the affinity for A2AR was determined. Two compounds, (2‐(3,3‐dimethylbutyl)‐9‐methyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐purin‐6‐amine ( 3 b ) and 4‐(6‐amino‐9‐methyl‐8‐(2H‐1,2,3‐triazol‐2‐yl)‐9H‐purin‐2‐yl)‐2‐methylbutan‐2‐ol ( 3 c ), exhibited good affinity against A2AR (Ki=0.4 nM and 2 nM , respectively) and high in vitro metabolic stability (89.5 % and 95.3 % recovery, respectively, after incubation with HLM for two hours). 相似文献