Eristanna Palazzolo

Current and Potential Use of Citrus Essential Oils

Since the Middle Ages, citrus essential oils (EOs) have been widely used for their bactericidal, virucidal, fungicidal, antipara- sitical, insecticidal, medicinal and cosmetic proprieties. Also nowadays, they find important applications in pharmaceutical, sanitary, cosmetic, agricultural and food industries. The best method to extract EOs from citrus plant tissue is steam distillation because of a vari- ety of extracted volatile molecules such as terpenes and terpenoids, phenol-derived aromatic components and aliphatic components. In vitro physicochemical assays classify most of them as antioxidants.

The nutritional composition of selected wild edible mushrooms from Sicily (southern Italy).

The wide consumption of wild fungi by the local population is the basis for an evaluation of the as yet unknown nutritional composition of some selected species. Wild edible mushrooms (Fistulina hepatica, Infundibulicybe geotropa, Laetiporus sulphureus, Macrolepiota procera var. procera and Suillus granulatus) were collected in a number of Sicilian (southern Italian) forest ecosystems and analysed according to standard methodologies of fungal analysis, for their basic composition (ash, water, protein, fat, carbohydrate and vitamin). The results showed that the investigated mushrooms could be suggested as a source of nutritional elements for the human diet.

CPMAS 13C NMR Characterization of Leaves and Litters from the Reafforestated Area of Mustigarufi in Sicily (Italy)

Reafforestation is generally based on the planting of exotic fast growing tree species suitable for adapting to even harsh environments. Once the introduced plants ameliorate soil conditions, they can be progressively replaced by au- tochthonous plant species. Reafforestation is applied worldwide. However, only few studies on the effect of reafforesta- tion on lands from Mediterranean regions are available. This paper reports the characterization by cross polarization 13 C NMR spectroscopy of fresh leaves and superficial litters from a reafforestated area in central Sicily (Italy). NMR assign- ment is attempted. A differentiation among the molecular systems within leaves and litters is also done on the basis of NMR assessment. Results showed that the main differences among the leaves of four forest trees (two eucalyptus spp., one cypress sp. and one pine sp.) occur in the distribution of the aromatic and alkyl carbons. In particular, the alkyl moie- ties in the eucalyptus spp. leaves were attributed to branched structures belonging to the eucalyptus oil, whereas linear fatty acids were more representetive in the NMR spectra of pine and cypress leaves. In addition, the aromatic carbons of the conifer leaves were assigned not only to lignin- and tannin-like structures, but also to common olefin carbons in un- saturated fatty acids and abietic acid-like systems. The spectra of the litters resembled, as expected, those of the leaves. However, the presence of very large carbohydrate NMR signals suggested that degradation processes were still ongoing in litters. A comparative evaluation of CPMAS 13 C NMR spectra was done by applying principal component analysis. This paper confirmed the suitability of CPMAS 13 C NMR spectroscopy in evaluating the differences among natural bio-masses

Seasonal variations of antimicrobial activity and chemical composition of essential oils extracted from three Citrus limon L. Burm. cultivars.

In order to investigate the seasonal variations of antimicrobial properties and chemical composition of essential oils (EOs), three different cultivars of Citrus limon L. Burm. spp. (Femminello Santa Teresa, Monachello and Femminello Continella) were collected at 6-week intervals, from December 2012 to April 2013, for a total of four harvests. The EOs were extracted from lemon peel by hydro-distillation. The antimicrobial activity, tested by paper disc diffusion method, was evaluated against common food-related pathogenic bacteria (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica and Enterobacter spp.). EOs were more effective against Gram-positive than Gram-negative bacteria at each collection time, but a strong strain dependence was evidenced. Monachello EOs showed the highest inhibition power. The chemical characterisation of the EOs performed by gas chromatography/mass spectrometry identified from 36 to 42 molecules. The chemical difference registered among samples and seasons may explain the different antimicrobial efficacies recorded.

Solid-State 1H-NMR Relaxation Properties of the Fruit of a Wild Relative of Eggplant at Different Proton Larmor Frequencies

ABSTRACT 1H longitudinal relaxation time profiles (T1) at different proton Larmor frequencies were registered for a solid-state plant tissue by using fast field cycling (FFC) nuclear magnetic resonance (NMR) spectroscopy. T1 distributions were obtained and the curves deconvoluted in order to differentiate among the different T1 components. Among the components, two were assigned to hydrophobic (e.g., fatty acid) and hydrophilic (e.g., saccharide) molecular systems, whereas the others were attributed to bulk and bound water. This paper shows for the first time solid-state FFC-NMR spectroscopy applied to plant tissue and reveals that relaxometry is a very promising technique for studying plant systems.

Mapping Quantitative Trait Loci Affecting Biochemical and Morphological Fruit Properties in Eggplant (Solanum melongena L.)

Eggplant berries are a source of health-promoting metabolites including antioxidant and nutraceutical compounds, mainly anthocyanins and chlorogenic acid; however, they also contain some anti-nutritional compounds such as steroidal glycoalkaloids (SGA) and saponins, which are responsible for the bitter taste of the flesh and with potential toxic effects on humans. Up to now, Quantitative Trait Loci (QTL) for the metabolic content are far from being characterized in eggplant, thus hampering the application of breeding programs aimed at improving its fruit quality. Here we report on the identification of some QTL for the fruit metabolic content in an F2 intraspecific mapping population of 156 individuals, obtained by crossing the eggplant breeding lines “305E40” × “67/3.” The same population was previously employed for the development of a RAD-tag based linkage map and the identification of QTL associated to morphological and physiological traits. The mapping population was biochemically characterized for both fruit basic qualitative data, like dry matter, °Brix, sugars, and organic acids, as well as for health-related compounds such chlorogenic acid, (the main flesh monomeric phenol), the two peel anthocyanins [i.e., delphinidin-3-rutinoside (D3R) and delphinidin-3-(p- coumaroylrutinoside)-5-glucoside (nasunin)] and the two main steroidal glycoalkaloids, solasonine, and solamargine. For most of the traits, one major QTL (PVE ≥10%) was spotted and putative orthologies with other Solanaceae crops are discussed. The present results supply valuable information to eggplant breeders on the inheritance of key fruit quality traits, thus providing potential tools to assist future breeding programs.

Key Biochemical Attributes to Assess Soil Ecosystem Sustainability

Soil is not a renewable resource, at least within the human timescale. In general, any anthropic exploitation of soils tends to disturb or divert them from a more “natural” development which, by definition, represents the best comparison term for measuring the relative shift from soil sustainability. The continuous degradation of soil health and quality due to abuse of land potentiality or intensive management occurs since decades. Soil microbiota, being ‘the biological engine of the Earth’, provides pivotal services in the soil ecosystem functioning. Hence, management practices protecting soil microbial diversity and resilience, should be pursued. Besides, any abnormal change in rate of innumerable soil biochemical processes, as mediated by microbial communities, may constitute early and sensitive warning of soil homeostasis alteration and, therefore, diagnoses a possible risk for soil sustainability. Among the vastness of soil biochemical processes and related attributes (bioindicators) potentially able to assess the sustainable use of soils, those related to mineralisation-immobilisation of major nutrients (C and N), including enzyme activity (functioning) and composition (community diversity) of microbial biomass, have paramount importance due to their centrality in soil metabolism. In this chapter we have compared, under various pedoclimates, the impact of different agricultural factors (fertilisation, tillage, etc.) under either intensive and sustainable managements on soil microbial community diversity and functioning by both classical and molecular soil quality indicators, in order to outline the most reliable soil biochemical attributes for assessing risky shifts from soil sustainability.

Sediment delivery processes and chemical transport in a small forested basin/Processus de production sédimentaire et transport chimique dans un petit bassin versant forestier

Abstract Because the properties of eroded soil affect the deposition phenomena and transport capacity of chemical materials by eroded particles, recent research is trying to link the grain-size distribution of the eroded sediment to that of the original soil in order to explain the enrichment of chemical content of the sediment with the respect to the parent soil. In this study, the spatial distribution of nitrogen, phosphorus and total organic carbon was firstly deduced using the measurements carried out in 47 soil samples distributed over a forested basin together with a kriging interpolation method. Then the load of each chemical was calculated at morphological unit and basin scales using the above-mentioned spatial distributions and sediment yield values calculated by the SEDD (SEdiment Delivery Distributed) model, which couples the universal soil loss equation with a spatial disaggregation criterion of sediment delivery processes. Finally, at basin scale, a new expression of the enrichment ratio of a given chemical was applied.

Degradation of long-chain n-alkanes in soil microcosms by two actinobacteria

The ability of two recently isolated actinobacteria, that degrade medium and long chain n-alkanes in laboratory water medium, was investigated in soil microcosms using different standard soils that were artificially contaminated with n-alkanes of different length (C12- C20- C24- C30). The two strains, identified as Nocardia sp. SoB and Gordonia sp. SoCp, revealed a similar high HC degradation efficiency with an average of 75% alkane degraded after 28 days incubation. A selectivity of bacteria towards n-alkanes of different length was detected as well as a consistent effect of soil texture and other soil physical chemical characteristics on degradation. It was demonstrated the specific aptitude of these selected strains towards specific environmental conditions.

Assessing hydrological connectivity inside a soil by fast-field-cycling nuclear magnetic resonance relaxometry and its link to sediment delivery processes

Connectivity is a general concept used to represent the processes involving a transfer of matter among the elements of an environmental system. The expression “hydrological connectivity inside the soil” has been used here to indicate how spatial patterns inside the soil (i.e., the structural connectivity) interact with physical and chemical processes (i.e., the functional connectivity) in order to determine the subsurface flow (i.e., the water transfer), thereby explaining how sediment transport due to surface runoff (i.e., the soil particle transfer) can be affected. This paper explores the hydrological connectivity inside the soil (HCS) and its link to sediment delivery processes at the plot scale. Soils sampled at the upstream- and downstream-end of three different length plots were collected together with sediments from the storage tanks at the end of each plot. All the samples were analyzed by traditional soil analyses (i.e., texture, Fourier transform infrared spectroscopy with attenuated total reflectance, C and N elemental contents) and fast-field-cycling (FFC) nuclear magnetic resonance (NMR) relaxometry. Results revealed that selective erosion phenomena and sediment transport are responsible for the particle size homogeneity in the sediment samples as compared to the upstream- and downstream-end soils. Moreover, while structural connectivity is more efficient in the upstream-end soil samples, functional connectivity appeared more efficient in the downstream-end and sediment samples. Further studies are needed in order to quantitatively assess FFC NMR relaxometry for HCS evaluation.