Vincenzo Sicari

A Comparison between the Chemical Composition of the Oil, Solvent Extract and Supercritical Carbon Dioxide Extract of Citrus medica cv. Diamante

Abstract Citrus medica L. cv. Diamante collected in Calabria (Italy) was extracted by different technologies. The traditional hydrodistillation and solvent methods were compared to the supercritical carbon dioxide extraction (SCF-CO2) performed at two fluid densities: the lowest at 250 g/dm3 and the highest at 875 g/dm3. The effect of the drying process on the peels was studied, and the oil loss was found to be low. The solubility power of CO2 (related to its density) was observed. An enrichment of the less-volatile components like sesquiterpenes, heterocyclic compounds and waxes was quantified in the SCF-CO2 extracts. The monoterpene hydrocarbons were about 95% in the hydrodistillates and in the pentane extract, but these components decreased in the SCF-extracts to a value lower than 85%. The sesquiterpenes were about 0.62% in the hydrodistillates and 1.40% in the pentane extract, but high quantities were found in the SCF-CO2 extracts: 5.64% in the extraction performed at low CO2 density and 12.09% at hi...

Optimization of a Solid-Phase Microextraction method for the Gas Chromatography-Mass Spectrometry analysis of blackberry (Rubus ulmifolius Schott) fruit volatiles

A Solid-Phase Microextraction method for the Gas Chromatography-Mass Spectrometry analysis of blackberry (Rubus sp.) volatiles has been fully optimized by means of a Box-Behnken experimental design. The optimized operating conditions (Carboxen/Polydimethylsiloxane fiber coating, 66°C, 20 min equilibrium time and 16 min extraction time) have been applied to the characterization for the first time of the volatile composition of Rubus ulmifolius Schott blackberries collected in Italy and Spain. A total of 74 volatiles of different functionality were identified; esters and aliphatic alcohols were the predominant classes in both sample types. Methylbutanal (2.02-25.70%), ethanol (9.84-68.21%), 2,3-butanedione (2.31-14.71%), trans-2-hexenal (0.49-17.49%), 3-hydroxy-2-butanone (0.08-7.39%), 1-hexanol (0.56-16.39%), 1-octanol (0.49-10.86%) and methylbutanoic acid (0.53-21.48%) were the major compounds in most blackberries analyzed. Stepwise multiple regression analysis of semiquantitative data showed that only two variables (ethyl decanoate and ethyl acetate) were necessary for a successful differentiation of blackberries according to their harvest location.

Bioactive and Antioxidant Activity from Citrus bergamia Risso (Bergamot) Juice Collected in Different Areas of Reggio Calabria Province, Italy

The chemical composition and antioxidant activity of juice extracted from seven samples of bergamot (Citrus bergamia Risso) collected in different areas of Reggio Calabria Province were investigated. The ascorbic acid, total polyphenol, and flavonoid contents were determined. Total flavonoids and polyphenols were analyzed by ultraviolet spectra, while flavanone content was analyzed by high-performance liquid chromatography. The antioxidant activity of the fractions was assessed using three representative assays: 2,2′-azinobis(3-ethylbenzothiazoline 6-sulfonic acid), 1,1-Diphenyl-2-picryl-hydrazyl radical quenching and β-carotene bleaching test. The main flavanones were naringin, neohesperedin, and neoeriocitrin, and their average content 242.4 ± 1.8, 183.0 ± 0.6, and 247.0 ± 1.4 mg mL–1, respectively. The results showed that bergamot juice possessed a good quality and a valuable source of health promoting constituents. In fact it contained eriocitrin, naringin, neoeriocitrin, and neohesperedin, which may contribute differentially to the antioxidant capacity.

Statistical analysis for improving data precision in the SPME GC-MS analysis of blackberry (Rubus ulmifolius Schott) volatiles

Statistical analysis has been used for the first time to evaluate the dispersion of quantitative data in the solid-phase microextraction (SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis of blackberry (Rubus ulmifolius Schott) volatiles with the aim of improving their precision. Experimental and randomly simulated data were compared using different statistical parameters (correlation coefficients, Principal Component Analysis loadings and eigenvalues). Non-random factors were shown to significantly contribute to total dispersion; groups of volatile compounds could be associated with these factors. A significant improvement of precision was achieved when considering percent concentration ratios, rather than percent values, among those blackberry volatiles with a similar dispersion behavior. As novelty over previous references, and to complement this main objective, the presence of non-random dispersion trends in data from simple blackberry model systems was evidenced. Although the influence of the type of matrix on data precision was proved, the possibility of a better understanding of the dispersion patterns in real samples was not possible from model systems. The approach here used was validated for the first time through the multicomponent characterization of Italian blackberries from different harvest years.

Antioxidant potential of extra virgin olive oils extracted from three different varieties cultivated in the Italian province of Reggio Calabria

In this study, the physicochemical properties and bioactive compounds of olive oils from cultivars “Roggianella”, “Sinopolese” and “Ottobratica”, grown in the province of Reggio Calabria (Italy) have been evaluated.Polyphenols are a large family of compounds found in fruits and vegetables, which exhibit strong antioxidant activity by scavenging different families of Reactive Oxygen Species (ROS).Dialdehydic form decarboxymethyl oleuropein aglycon, hydroxytyrosol acetate, dialdehydic form oleuropein aglycon, pinoresinol, 1-acetoxypinoresinol, tyrosol and vanillic acid were the main phenolic compounds in all samples analyzed. Pinoresinol was the most abundant compound in the lignin fraction. In all oil samples analyzed the highest antioxidant capacity was attributed to Roggianella oil (36.85% I of DPPH and 4.07% I of ABTS) compared to Ottobratica (27.37% I of DPPH and 2.52% I of ABTS) and Sinopolese (18.33% I of DPPH and 1.72% I of ABTS). The main characteristics of the Roggianella cultivar were a very high concentration of total phenols (530 mg/kg of gallic acid) and α-tocopherol (211 mg/kg).

Portulaca oleracea L. (Purslane) extracts display antioxidant and hypoglycaemic effects

Purslane (Portulaca oleracea L.) is a member of the family Portulacaceae. Due to its many health benefits, it is listed in a World Health Organization database. The aim of this work is to investigate the purslane extracts for their chemical profile and bioactivity.In this study, two different solvents (MeOH/H2O and EtOH) were applied to fresh and dried leaves. The extracts were analysed using HPLC-DAD. Phenolic acids (caffeic acid, p-coumaric acid and ferulic acid) and flavonoids (apigenin, kaempferol, luteolin, quercetin, isorhamnetin, kaempferol-3-O-glucoside and rutin) were identified in all samples. Quercetin and p-coumaric acid were the most abundant compounds. Total antioxidant activity was measured by using the ABTS and DPPH tests, and the ferric reducing antioxidant power (FRAP) assay. Hypoglycaemic properties were investigated via the inhibition of carbohydrate-hydrolysing enzymes, α-amylase and α-glucosidase.Fresh hydroalcoholic purslane extract exhibited the highest radical scavenging potential in both ABTS and DPPH test (IC50 values of 52.86 and 66.98 μg/mL, respectively), whereas dried hydroalcoholic purslane extract showed the highest α-glucosidase inhibitory potential (IC50 value of 45.05 μg/mL). Collectively these data show the health properties of this widely consumed salad plant.

Comparison of the Volatile Component of the Essential Oil of Kumquat (Fortunella margarita swingle) Extracted by Supercritical Carbon Dioxide, Hydrodistillation and Conventional Solvent Extraction

Abstract A study was performed on kumquat peel extracted by different methods: hydrodistillation, solvent and supercritical carbon dioxide (SC-CO2) extractions at a density of 281 g/dm3 (80 bar and 40°C of temperature) and 875 g/dm3 (250 bar and 40°C temperature). A total of 24 compounds were quantified: 8 monoterpene hydrocarbons, 6 terpene alcohols, 1 terpene aldehyde, 1 ketones terpene, 4 terpene esters, 4 sesquiterpene hydrocarbons. The amount of the major compound, limonene, in the essential oil obtained from Kumquat peel is high (96%), followed myrcene (1.6-1.7%) and the germacrene-D (0.9-1.4%). The three studied extractions (hydrodistillate, solvent and SC-CO2) present a similar composition regarding to limonene, myrcene and germacrene-D.

Phytochemical properties and antioxidant potential from Citrus bergamia , Risso (bergamot) juice extracted from three different cultivars

In plant-derived products there are naturally occuring bioactive compounds: that is, substances with or without nutritional value, having biological activity in the prevention of disease development, thus protecting human health. The following physical and nutritional properties of three bergamot cultivars (Castagnaro, Fantastico and Femminello) were determined and compared: pH, titratable acidity, vitamin C, total flavonoids, total polyphenols, antocianyn, bioactive molecules and antioxidant capacity (ABTS and DPPH assay). The comparison data, were found to be statistically different. In all juice samples analyzed the highest antioxidant capacity was found in Castagnaro juice (64.21% I of DPPH and 1.97% I of ABTS) compared to Fantastico (44.48% I of DPPH and 1.83% I of ABTS) and Femminello (33.39% I of DPPH and 1.13% I of ABTS). These differences could be attributed to the individual characteristics of these cultivars.