Recovery of flavonoids from three-phase olive pomace by aqueous ethanol extraction

A three-phase olive pomace (OP), the solid by-product originating from the production of olive oil, was investigated as a potential source of flavonoids. Flavonoids were extracted by an environmentally friendly procedure using aqueous ethanol as solvent. The flavonoid content of OP, expressed as quercetin equivalents (QE) per unit weight of dry material, was 25.28 ± 0.93 mg QE/g. To evaluate the effects of temperature (T), extraction time (E), liquid-to-solid ratio (R) and solvent composition (C) on the yield of flavonoid extraction (y), a Central Composite Design (CCD) coupled with Response Surface Methodology (RSM) was used. Statistical analysis of the results showed that T was the most influential factor, followed by E, R and C. A reduced polynomial model was developed by the stepwise regression method which provided an accurate description of the extraction process. Maximization of the response variable gave: ymax = 90.5% at T = 69.9 °C, E = 212 min, R = 36.7 mL/g and C = 43.7%. Overall, the obtained results support the use of three-phase OP as a source of flavonoids and give useful indications on the influence of process variables on their recovery

Evaluation of dissolved organic carbon (DOC) as a measure of cell wall degradation during enzymatic treatment of microalgae

The feasibility of using Dissolved Organic Carbon (DOC) measurements as a means to assess the efficacy of an enzyme-assisted pretreatment on the recovery of lipids from microalgae was investigated. Attention was focused on Nannochloropsis sp., a marine microalga of great biotechnological interest for its ability to accumulate large amounts of lipids and other valuable compounds. The enzymatic pretreatment was carried out using two commercial enzyme preparations, one (CEL) rich in cellulase and the other (GMA) rich in galactomannase. Experiments were performed according to a fractional two-level factorial design. The factors studied were temperature (15–75 °C), pH (2–8), pretreatment time (30–270 min), CEL dosage (0–20mg/g) and GMA dosage (0–2 mg/g). DOC was determined by a TOC analyzer and used as the response variable. Under the experimental design conditions, temperature, pH, pretreatment time and CEL dosage were found to be statistically significant (p < 0.05), with the former factor being the most influential. No significant interactions were observed between the main factors, indicating that each of them exerted its effect independently of the others. A good correlation was also found between the measured DOC values and the yields of lipid extraction from the enzymatically treated biomass, demonstrating that DOC measurements can be used to quantify the enzyme-induced degradation of algal cell walls

Extraction of bioactive polyphenols with high antioxidant activity from bilberry (Vaccinium myrtillus L.) processing waste

Bioactive polyphenols were extracted from the peel fraction of bilberry processing waste using aqueous ethanol as solvent. A response surface methodology was used to evaluate the effects of liquid-to-solid ratio (R), solvent composition (C), extraction time (E) and temperature (T) on the extraction yield. The following optimal conditions were determined: R = 30 mL/g, C = 57%, E = 160 min, T = 40 °C. Phenolic extracts with a polyphenol content of 83.75 ± 4.16 mg GAE/g and an antioxidant activity of 7.64 ± 0.43 mmol TE/g were also produced using a batch extractor operating under optimal process conditions

Antibacterial and anti-quorum sensing activities of selected italian honeys against antibiotic-resistant pathogens

Three nectar honeys (eucalyptus, thyme and forest) and two honeydew honeys (fir and Metcalfa) from Italy were tested for their antibacterial activity against pathogens commonly associated with wound and burn infections, including methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE) and vancomycin-resistant Enterococcus faecalis (VREF). All honeys showed bactericidal activity against the microorganisms used, with honeydew honeys being the most effective. They also inhibited, in a dose-dependent manner, violacein production in Chromobacterium violaceum, thus demonstrating their ability to affect quorum sensing-regulated biofilm formation. Overall, the results obtained suggest that the honeys examined may have potential for developing natural antimicrobial compositions or dressings for the treatment of infected wounds or burns

Production of metal nanoparticles by agro-industrial wastes. A green opportunity for nanotechnology

The feasibility of producing silver nanoparticles (Ag NPs) using phenolic extracts from agro-industrial wastes as reducing agents was investigated. Phenolic extracts were obtained from bilberry wastes (BW) and spent coffee grounds (SCG) with aqueous ethanol as extraction solvent. Experiments were carried out in batch at 25 °C by adding appropriate amounts of phenolic extracts to a silver nitrate aqueous solution. The formation of Ag NPs was monitored spectrophotometrically by measuring the intensity of the surface plasmon resonance (SPR) band of silver at 415-435 nm. Depending on the process conditions, the synthesis of Ag NPs was completed in 3 to 5 hours. Characterization of the resulting reaction products by XRD, SEM and DLS showed that nanoparticles were formed with a spherical shape and an average size of 10-20 nm. Overall, the results obtained suggest that BW and SCG could be used as a source of reducing agents for the production of metal NPs and that agro-industrial wastes may represent a valid alternative to the use of microorganisms, whole plants or plant parts for the biogenic synthesis of NPs

Kinetics of lycopene degradation in sunflower and grape seed oils

The stability of lycopene in two vegetable oils, sunflower seed oil (SSO) and grape seed oil (GSO), was investigated by analyzing the carotenoid degradation kinetics in the temperature range of 10–40°C. A tomato oleoresin containing 6% (w/w) of lycopene was used to prepare lycopene-enriched oil samples. Analysis of kinetic data showed that lycopene degradation follows first-order kinetics, with an apparent activation energy of 70.7 kJ mol–1 in SSO and 69 kJ mol–1 in GSO. The estimated half-life of lycopene was found to depend on oil type and storage temperature. At 20°C, it varied between 59 and 122 days, while at 4°C it was comprised between 302 and 650 days. At all temperatures, lycopene was more stable in SSO than in GSO, which is likely due to the higher content of antioxidant compounds in SSO

UHPLC-PDA-ESI-TOF/MS metabolic profiling and antioxidant capacity of arabica and robusta coffee silverskin: antioxidants vs phytotoxins

A deeper knowledge of the chemical composition of coffee silverskin (CS) is needed due to the growing interest in its use as a food additive or an ingredient of dietary supplements. Accordingly, the aim of this paper was to investigate the metabolic profile of aqueous extracts of two varieties of CS, Coffee arabica (CS-A), Coffee canephora var. robusta (CS-R) and of a blend of the two (CS-b) and to compare it to the profile of Coffee arabica green coffee (GC). Chlorogenic acids, caffeine, furokauranes, and atractyligenins, phytotoxins not previously detected in CS, were either identified or tentatively assigned. An unknown compound, presumably a carboxyatractyligenin glycoside was detected only in GC. Caffeine and chlorogenic acids were quantified while the content of furokauranes and atractyligens was estimated. GC and CS were also characterized in terms of total polyphenols and antioxidant capacity. Differences in the metabolites distribution, polyphenols and antioxidant capacity in CG and CS were detailed

Agathological Realism: Searching for the Good beyond Subjectivity and Objectivity or On the Importance of being Platonic.

1Pointing to a radical concept of 'self-givingness' and self-transcendence, Plato’s notion of good offers a valuable means for delineating a realism which eliminates any dichotomy between subjectivity and objectivity, knowledge and morality, ethics and ontology. Plato's suggestions can be discovered in combining the characterization of the Demiurge given in the Timaeus with the analogy between the supreme Good and the sun presented in the Republic, as well as explicating the analogy between the Good and the sun with reference to the image of the intelligible sphere of light. The resulting notion of good could be integrated into the phenomenal dimension of our knowledge and perception, helping to illustrate the reality of the way that knowledge and perception transcend any separation between interiority and exteriority, self and world, individuality and community.openopenLavecchia, SalvatoreLavecchia, Salvator

Supporto nutrizionale parenterale in medicina veterinaria: stato dell'arte e applicazioni cliniche.

Riassunto L'importanza della nutrizione in ambito ospedaliero non può essere sottovalutato. La malnutrizione è un problema comune e serio soprattutto nei pazienti in condizioni critiche in cui un bilancio energetico negativo è associata ad un aumento di morbilità e mortalità. L'aumentata incidenza di complicazioni attribuibili a malnutrizione è correlata ad un aumento dei tempi di ospedalizzazione e dei costi sanitari complessivi. Sebbene una nutrizione enterale precoce sia il metodo preferito per alimentare i pazienti in condizioni critiche, la nutrizione enterale da sola spesso non riesce a fornire adeguate calorie e sostanze nutritive nei pazienti critici, che hanno frequentemente un metabolismo aumentato. La nutrizione parenterale, o l'integrazione di una nutrizione enterale insufficiente con una nutrizione parenterale, può ottimizzare il sostegno nutrizionale ed evitare un bilancio energetico negativo nei pazienti critici, in modo da migliorarne il decorso clinico. La nutrizione parenterale è utilizzata sempre più per sostenere cani e gatti ricoverati in ospedale, ma le pubblicazioni sulla valutazione dei risultati in medicina veterinaria sono limitate. Scopo di questo lavoro è di rivedere i concetti clinici alla base dell'uso della nutrizione parenterale nella letteratura medica veterinaria in cani e gatti. Abstract The significance of nutrition in the hospital setting cannot be underestimated. Malnutrition is a common and serious problem particularly in critically ill patients in which a negative energy balance has been associated with increased morbidity and mortality. The increased incidence of complications attributable to malnutrition correlates with increased length of hospital stay and overall health care costs. Although early enteral nutrition is the preferred method of feeding critically ill patients, enteral nutrition alone often fails to supply adequate calories and nutrients to critically ill patients, who are frequently hypermetabolic. Parenteral nutrition, or supplementation of insufficient enteral nutrition with parenteral nutrition, may optimize nutritional support and avert negative energy balance in critically ill patients, thereby improving outcomes. Parenteral nutrition is increasingly used to support hospitalized dogs and cats. Published assessments of outcome are limited. The purpose of this work is to review the clinical concepts behind the use of the parenteral nutrition in veterinary medicine literature in dogs and cats