Search results for " oil"
showing 10 items of 1049 documents
Essential oil compositions of Teucrium fruticans, T. scordium subsp. scordioides and T. siculum growing in Sicily and Malta
2020
In the present study, the chemical composition of the essential oils from the aerial parts of Teucrium fruticans L. collected in Sicily and Malta, Teucrium scordium subsp. scordioides (Schreb.) Arcang. and Teucrium siculum (Raf.) Guss., collected in Sicily, were evaluated by GC-MS. The main volatile components of both T. fruticans collections were germacrene D (29.4% and 50.0%), (E)-β-caryophyllene (19.6% and 21.9%), and 1-octen-3-ol (19.7% and 7.4%); T. scordium subsp. scordioides essential oil was rich in caryophyllene oxide (25.8%), α-pinene (19.4%) and β-pinene (8.5%); T. siculum essential oil was rich in (E)-β-caryophyllene (30.9%), 1-octen-3-ol (9.0%), α-humulene (8.6%) and germacrene…
An experimental investigation on the long-term compatibility of preheated crude palm oil in a large compression ignition diesel engine
2018
An experimental study was carried out on a large stationary compression ignition engine to evaluate the long-term compatibility and durability issues associated with the use of crude palm oil as fuel. Two different preheating temperatures (60 and 80 °C) were adopted to assess the potential improvements related to lower fuel viscosity. The results obtained, in terms of in-cylinder carbon deposits and engine wear, were compared with the results obtained using ordinary diesel fuel. For each fuel and preheating temperature, the engine was operated for 300 consecutive h, during which several engine lubricant samples were collected and analysed to determine soot and fuel contaminations, viscosity…
On the self-heating behavior of upgraded biochar pellets blended with pyrolysis oil: Effects of process parameters
2020
Abstract Biochar obtained from biomass pyrolysis is a promising carbon neutral material which can be used in substitution of fossil coal and coke in metallurgical applications. Biochar’s mechanical properties improve significantly without compromising reactivity, when upgraded by densification with pyrolysis oil and reheated. However, upgraded biochar pellets use in the industry is limited due to the risks associated with self-heating. This issue must be seriously considered for further industrial production of upgraded biochar pellets. Self-heating oven tests are generally time-consuming and limit the possibility of testing various potential solutions. The aim of this work was both to inve…
Assessment of the antioxidant and antibacterial activities of different olive processing wastewaters.
2017
Olive processing wastewaters (OPW), namely olive mill wastewater (OMW) and table-olive wastewaters (TOW) were evaluated for their antibacterial activity against five Gram-positive and two Gram-negative bacteria using the standard disc diffusion and thin layer chromatography (TLC)-bioautography assays. Disc diffusion screening and bioautography of OMW were compared to the phenolic extracts of table-olive brines. Positive activity against S. aureus was demonstrated. The optimization of chromatographic separation revealed that hexane/acetone in the ratio of 4:6 was the most effective for phenolic compounds separation. A HPLC-MS analysis was performed showing that only two compounds, hydroxytyr…
The effect of enriching milk-based beverages with plant sterols or stanols on the fatty acid composition of the products
2013
Five plant sterol (PS)-enriched dairy products from the Spanish market were characterised for fatty acids (FA), volatile compounds and lipid stability. The ingredients used for PS enrichment by the food industry may come from different sources, thus influencing the composition and stability of the lipid fraction. In this study, the FA profile proved highly variable among samples, not agreeing with the nutritional labelling of the products. The volatile profile was characterised. A total of 55 volatile compounds were identified in the samples by GC–MS. Concentrations of hexanal (from 1.1 to 7.5 ng/g), nonanal (from 0.9 to 1.2 ng/g) and decane (from n.d. to 11.9 ng/g) indicated a low lipid ox…
Composition of essential oil of lemon thyme (Thymus × citriodorus) at different hydrodistillation times.
2018
Distillation time can both to optimise the production and to engineer the composition of essential oil in essential oil bearing plants. Purpose of this study was to evaluate the effect of duration of hydrodistillation on composition of essential oil of Thymus × citriodorus, the natural source of commercially important geraniol and citral, a component with valuable biological properties. Essential oils were isolated by hydrodistillation at different distillation times and analysed by GC/MS analytical methods. Increase in percentage of essential oil during all hydrodistillation time gradient was uneven. Elongation of hydrodistillation time decreased percentages of monoterpenes but increased p…
Supercritical carbon dioxide extraction of seed oil from yellow horn (Xanthoceras sorbifolia Bunge.) and its anti-oxidant activity
2010
Supercritical fluid carbon dioxide (SF-CO(2)) extraction (SFE) of seed oil from yellow horn and its anti-oxidant activity were investigated. The effects of CO(2) flow rate and particle size were firstly optimized, and a central composite design (CCD) combined with response surface methodology was used to study the effects of extraction pressure, temperature and time on the extraction yields. A maximal extraction yield of 61.28% was achieved under optimal conditions of extraction pressure 30 MPa at 45.68 degrees C, 2.08 h and CO(2) flow rate 12 kg/h with 0.5mm particle size. By analyzing the chemical composition of the seed oil, we found that the content of unsaturated fatty acids was approx…
Follow-up trends of parasite community alteration in a marine fish after the Prestige oil-spill: shifting baselines?
2008
This study evaluates the follow-up trends in the composition and structure of the parasite communities in the marine sparid Boops boops after the Prestige oil-spill. A total of 400 fish comprising 11 seasonal samples was analyzed from three impacted localities on the Atlantic coast of Spain. A large number of parasite species was recovered only after the spill thus suggesting a substantial alteration of the marine food webs. Post-spill communities exhibited higher richness and abundance due to the significant changes in the abundance of the common species, the latter indicating accelerated parasite transmission rates. Multivariate analyses at two nested scales detected a directional trend i…
Determination of the cultivar and aging of Sicilian olive oils using HPLC-MS and linear discriminant analysis
2010
A large number of certified samples (84) of Sicilian olive oils arising from the eight cultivars most represented in Sicily (Biancolilla, Cerasuola, Moresca, Nocellara del Belice, Nocellara Etnea, Oglialora Messinese, Brandofino and Tonda Iblea) have been collected and analyzed by HPLC/MS using an atmospheric pressure chemical ionization (APCI) source. The sample preparation is very simple; in fact, the oil samples are diluted without any chemical derivatization. A following statistical data treatment by general discriminant analysis (GDA) allows the determination of the olive oil cultivar. Furthermore, changes in the composition of glyceridic components of the olive oils lead to easy discr…
Chemical fingerprint of outdoor PM2.5 in Malta
2015
Intro: RESPIRA (EU Funded - Italia-Malta 07-13) indicated that living in Malta is a risk factor for asthma. Aim: To determine the chemical profile of PM2.5 in Malta, and compare with reference values. Methods: Using FAI pumps at 10l/min/48hr, samples were collected on Teflon and Quartz filters from 6 schools and 46 homes in Malta. Total ICP-MS measurement (Residual+extracted), X ray Fluorescence, and thermo-optical methods(TO) were used for analysis by CNR in Rome. Aeroqual IQM60 counters were used for total PM2.5 mass. All data in ng/m3, Mean, (1st to 3rd quartile) of all 48 hour measurements.