Roberta Piccaglia

Lutein and lutein ester content in different types of Tagetes patula and T. erecta

Abstract Lutein and lutein fatty acid ester content in two different parts (petals and calyces) of flower-heads from different types of marigold belonging to the species Tagetes patula and T. erecta were evaluated by HPLC combined with a diode array detector (DAD). A typical chromatographic profile of pigments was characterized by the simultaneous presence of lutein and eight lutein esters. Relevant quantitative differences were found among the marigold types which had a total content of pigments ranging from 17 to 570 mg/100 g in the petals and from 0.4 to 18.6 mg/100 g in the calyces. The petal colours were also defined by the L *, a * and b * values determined by a chroma meter. Differences in petal colour were well related to the pigment content and good correlations between pigment concentration and L * and a * values were found.

Antibacterial and antioxidant properties of Mediterranean aromatic plants

Abstract Eleven aromatic plants (lavender, thyme, winter savory, rosemary, sage, peppermint, chanomile, Roman chamomile, French tarragon, bitter and sweet fennel), typical of the Mediterranean area, were grown in Northern Italy and their essential oils obtained by steam distillation. The distilled oils were analysed for their antibacterial activities against 25 microorganisms and also for any antioxidant properties. The chemical composition of the essential oils was related to their effectiveness. Thyme and winter savory oils exhibited the greatest inhibition against the growth of all the tested organisms possibly due to the high content of thymol and carvacrol respectively. The Roman chamomile oil exhibited the highest antioxidant activity.

Effects of Variety and Ontogenic Stage on the Essential Oil Composition and Biological Activity of Fennel (Foeniculum vulgare Mill.)

ABSTRACT The essential oils obtained from three varieties of Foeniculum vulgare Mill. (dulce, vulgare and azoricum) harvested at three ontogenic stages (early, late waxy and ripe seed) were evaluated for their chemical composition and biological activity. (E)-anethole, limonene and fenchone contents were greatly influenced by the varieties and by the harvesting times. The antibacterial activity of the various oils against 25 microorganisms was evaluated. The inhibition of Aeromonas hydrophila, Alcaligenes faecalis and Clostridium sporogenes was of particular interest and there was a marked antifungal potency against Aspergillus niger.

Effect of planting density and harvest date on yield and chemical composition of sage oil

Abstract The yield and composition of sage (Salvia officinalis L.) oil cultivated in northern Italy and subjected to different growing conditions (planting densities and harvest managements) were evaluated. Sage harvested in spring at flowering stage (1st cut) gave the highest yields of fresh and dried matter. A harvesting regimen with three successive harvests produced the highest biomass yield. Twenty-nine compounds were identified in the oil. The oil of sage harvested at flowering stage greatly differed in composition from the oil of sage cut at vegetative stage. Very important differences were observed also between the oil composition of sage harvested at vegetative stage in spring and in the autumn. The highest content of thujones was found in the oils of sage harvested in autumn.

Characterization and Yield Evaluation of Essential Oils from Different Tagetes Species

Abstract Six species of Tagetes (T. erecta, T. filifolia, T. lucida, T. minuta, T. patula and T. tenuifolia), grown in northern Italy, were evaluated for their morpho-phenological characteristics, biomass yield and essential oil composition. The species showed marked differences in plant height, shape, flower size, habit and vegetative cycle length as found for T. filifolia which finished the vegetative cycle without reaching the flowering stage. The leaves always showed fresh material yields many fold higher than flowers (on average 26.8 and 4.4 t ha,−1 respectively). Tagetes erecta and T. patula produced significantly higher amounts of flowers than the other species (7.3 and 6.4 t ha,−1 respectively), whereas Tagetes lucida and T. filifolia were those with the highest yields of leaves (41.9 and 33.3 t ha,−1 respectively). The oils isolated by steam distillation from the flowers and leaves, were analyzed by GC and GC/MS. The flowers and the leaves of each species showed very similar qualitative oil compositions and the leaves, on average, were richer in oil contents. The oil yields between the flowers and leaves showed differences highly significant (on average 1.8 and 150.3 kg ha,−1 respectively). Tagetes erecta, T. minuta, T. patula and T. tenuifolia comprised the same pool of components (dihydrotagetone, tagetones, ocimenones and piperitone) which showed different and typical ratios in each species and, piperitone, (E)-tagetone, terpinolene and (E)-ocimenone were those more abundant respectively. Tagetes filifolia and T. lucida had methyl chavicol as the main compound.

Characterization of Essential Oil from a Satureja montana L. Chemotype Grown in Northern Italy

ABSTRACT Satureja montana L. grown in Italy has been characterized on the basis of its essential oil composition. Qualitative and quantitative analyses of steam distilled oil were performed by GC and GC/MS. Forty-four compounds were identified (30 monoterpenes and 14 sesquiterpenes). Over two consecutive seasons, oil produced was found to contain carvacrol (26.38–41.23%), γ-terpinene (1.40–6.16%) and p-cymene (11.00–16.32%) as main constituents. Environmental parameters such as precipitation and temperature were found to have an effect on the oil yield and composition of the oil produced.

Effects of Harvesting Date and Climate on the Flavonoid and Carotenoid Contents of Marigold (Calendula officinalis L.)

The flavonoid and carotenoid contents and agronomic parameters of an Italian type of marigold (Calendula officinalis L.) were evaluated over a 2-year trial performing two annual cuts during the flowering period. The flavonoids and carotenoids of the marigold petals were characterized by HPLC with a photodiode array detector. The number of flower heads per plant and the yield of heads and petals were always higher in the second cut, but the pigment content greatly differed in the 2 years. Glycosides of quercetin and isorhamnetin were the predominant components of the flavonoids, while β-carotene and lutein were the most abundant carotenoids.

Effect of Mineral Fertilizers on the Composition of Salvia officinalis Oil

ABSTRACT Mineral fertilization (N,K,P) trials on Salvia officinalis L. were evaluated on the basis of fresh plant and essential oil yields. Quali-quantitative oil characterization was performed using two columns of different polarity. The results of quantitative analyses are reported. It was found that the concentrations of β-thujone, camphor, p-cymene, β-caryophyllene, α-humulene and caryophyllene oxide were affected significantly by the various concentrations of fertilizers.

Optimization of electrochemical detection in the high-performance liquid chromatography of lignin phenolics from lignocellulosic by-products.

Free phenolic acids and aldehydes (p- and o-hydroxyphenylacetic acid, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillic acid, vanillin, syringic acid, p-coumaric acid, syringaldehyde and ferulic acid) were detected in wheat straw extracts by high-performance liquid chromatography with a dual-cell electrochemical detector operated in the redox mode. Phenolics were oxidized with coulometric efficiency in the first cell (+ 1.00 V), then detected by reduction in the second cell (-0.20 V). Compared with the oxidative mode, the reductive detection mode has the advantage of being unaffected by large amounts of interferents eluting at the front of the chromatogram that interfere with the detection of small and early eluting compounds. Hydrodynamic voltammograms in the oxidative, reductive and screen-out modes are presented and the corresponding detection limits for real sample are discussed. Perfect linearity of response was found in the range 5 x 10(-7) - 5 x 10(-5) M and detection limits were of the order of 50-500 fmol injected.

Characterization by pyrolysis-gas chromatography of wheat straw fermented with white rot fungus Stropharia rugosoannulata

Abstract Pyrolysis-gas chromatography was applied to a study of the changes in organic material during fungal fermentation processing of wheat straw. Native straw samples were subjected to pyrolysis using a 100 CDS Pyroprobe heated filament pyrolyser coupled directly to the injector of the gas chromatograph. Twenty-one pyrolytic fragments were identified by retention times and mass spectrometry using an on-line gas chromatography/ion trap detector instrument. Pyrograms are reported, as well as quantitative and statistical analyses of fifteen compounds, showing significant changes for six compounds.