Fast field cycling NMR relaxometry characterization of biochars obtained from an industrial thermochemical process

Purpose

Biochar has unique properties which make it a powerful tool to increase soil fertility and to contribute to the decrease of the amount of atmospheric carbon dioxide through the mechanisms of C sequestration in soils. Chemical and physical biochar characteristics depend upon the technique used for its production and the biomass nature. For this reason, biochar characterization is very important in order to address its use either for agricultural or environmental purposes.

Materials and methods

Three different biochars obtained from an industrial gasification process were selected in order to establish their chemical and physical peculiarities for a possible use in agronomical practices. They were obtained by charring residues from the wine-making industry (marc) and from poplar and conifer forests. Routine analyses such as pH measurements, elemental composition, and ash and metal contents were performed together with the evaluation of the cross-polarization magic angle spinning (CPMAS) ¹³C NMR spectra of all the biochar samples. Finally, relaxometry properties of water-saturated biochars were retrieved in order to obtain information on pore size distribution.

Results and discussion

All the biochars revealed basic pH values due to their large content of alkaline metals. The quality of CPMAS ¹³C NMR spectra, which showed the typical signal pattern for charred systems, was not affected by the presence of paramagnetic centers. Although paramagnetism was negligible for the acquisition of solid state spectra, it was effective in some of the relaxometry experiments. For this reason, no useful information could be retrieved about water dynamics in marc char. Conversely, both relaxograms and nuclear magnetic resonance dispersion profiles of poplar and conifer chars indicated that poplar char is richer in small-sized pores, while larger pores appear to be characteristic for the conifer char.

Conclusions

This study showed the potential of relaxometry in revealing chemical?Cphysical information on industrially produced biochar. This knowledge is of paramount importance to properly direct biochar agronomical uses.     

Effects of afforestation with four unmixed plant species on the soil–water interactions in a semiarid Mediterranean region (Sicily, Italy)

Purpose

An assessment of the effect of plant cover on the properties of four afforested soils in central Sicily was performed with the aim of discriminating among them after 60?years of afforestation.

Materials and methods

Chemical and biochemical soil analyses were coupled to fast field cycling (FFC) NMR relaxation investigations in order to monitor surface interactions of water in water-saturated soils.

Results and discussion

The traditional soil analyses revealed that the most stable soil properties such as soil texture and pH are not affected by 60?years of afforestation. Soils developed under eucalyptus trees showed larger amounts of hydrophilic organic matter as compared to the soils under pines and cypresses. FFC-NMR relaxometry data revealed that water, partitioned in clay-, loam-, and sand-type pores, showed longitudinal relaxation time values affected by the interactions with the soluble carbon content.

Conclusions

The results of the present study evidenced the potential of FFC-NMR relaxometry in differentiating the effect of diverse plant cover on chemical and hydrological properties of soils developed on the same parent material. In fact, in contrast with the traditional physicochemical and biochemical soil characterizations, which were unable to reveal differences among soils afforested with different plant species, FFC-NMR was capable of monitoring differences in water dynamics as affected by the presence of the most soluble soil organic material.     

A ω-secalin contained decamer shows a celiac disease prevention activity

Celiac disease (CD) is an autoimmune permanent enteropathy that is triggered in susceptible individuals after the ingestion of gluten, a storage protein fraction presents in wheat, rye and barley endosperm. Specific gluten peptides can bind to HLA-DQ2/8 and induce lamina propria CD4⁺ T cell responses causing damage of the small intestine mucosa. Recent studies suggested that beside immunodominant and toxic epitopes, wheat gluten also contains epitopes capable of preventing the mucosal response in vitro. Among them, a decapeptide (QQPQDAVQPF) from wheat was reported to have an antagonist effect on the agglutination of K562(S) cells and celiac T-cell activation, although the corresponding nucleotidic sequence remained unknown. This study was therefore designed to clone the sequence encoding the protein carrying the decapetide with CD protective properties. A ω-secalin gene encoding containing the decapeptide QQPQRPQQPF was isolated. Although the decapeptide was not identical to the one previously described, QQPQRPQQPF showed the same capability to prevent K562(S) cell agglutination and celiac mucosa immune activation induced by toxic gliadins. The ω-secalin gene was found in wheat carrying the wheat–rye chromosomal translocations 1BL.1RS. The identification of this immunomodulatory gliadin sequence, naturally occurring in cultivars of wheat toxic for celiac patients, might offer new therapeutic strategies for CD.     

Environmental conditions in a lagoon and their possible effects on shellfish contamination by Giardia and Cryptosporidium

Over a 1-year period, we carried out an analysis for the presence of Giardia and Cryptosporidium (oo)cysts in 934 specimens taken from four species of shellfish farmed in the Varano Lagoon. We also studied the chemical, physical and meteo-climatic parameters in the same environment, to evaluate the possible effects of environmental conditions on protozoan contamination in farmed shellfish. Using both IF and molecular tests, all 38 pools of shellfish gave negative values for Giardia and Cryptosporidium oo/cysts, thus confirming previous investigations. The environmental factors considered having a negative influence on the survival of Giardia and Cryptosporidium are high water temperatures (8–29°C) and high salinity levels (23–32?ppt). However, the small amount of freshwater discharged into the lagoon (up to 0.0091?m³ s^?1), the long-lasting solar irradiation (mean of 896?W?m^?2) and the shallowness of the lagoon (mean 2.5?m) may also have a synergic effect in limiting the presence of Giardia and Cryptosporidium in the lagoon.     

Identification of herbaceous hosts of the <Emphasis Type="Italic">Grapevine Pinot gris virus</Emphasis> (GPGV)

Grapevine Pinot gris Virus (GPGV) is a single stranded RNA of the genus Trichovirus infecting grapevine (Vitis vinifera) and associated with stunting, chlorotic mottling and leaf deformation symptoms. During a monitoring of GPGV infection in vineyards of the Trentino region in Italy, we have detected the virus in the herbaceous plants Silene latifolia subsp. Alba (Mill.) (bladder campion) and Chenopodium album L. (white goosefoot), which showed symptoms of viral infection. The full-length GPGV RNA genome, amplified from these infected hosts, was sequenced and a phylogenetic analysis revealed that its closest relative is the strain SK13, recently isolated in Slovakia. Our results indicate that herbaceous plants can be considered as a reservoir for the GPGV virus. This finding is important for studying the epidemiological aspects of GPGV disease and to formulate appropriate control measures.     

Is meat quality from Longissimus lumborum samples correlated with other cuts in horse meat?

The present work aims to investigate if the variation of each parameter in Longissimus lumborum muscle could correspond to the same or to a similar variation of the parameter in the other muscles. The work presents results of Pearson's correlations between Longissimus lumborum samples and other muscle samples, such as Biceps femoris, Rectus femoris, Semimembranosus, Supraspinatus and Semitendinosus in horse meat. A total of 27 male IHDH (Italian Heavy Draught Horse) breed foals were employed. They were slaughtered at 11 months of age and the above‐mentioned muscles were sampled. The Longissimus lumborum muscle showed to be representative of other muscles and of the whole carcass for some chemical parameters (moisture, protein and ash) and for some fatty acids profile patterns such as C12:0, C14:0, total monounsaturated fatty acid and polyunsaturated fatty acid, but poor correlations were recorded for intramuscular fat concentration, rheological and colorimetric parameters. Although almost all the qualitative parameters in meat are affected by the anatomical site and by the muscle, the Longissimus lumborum is often not representative in horse meat with regard to modifications of this parameters.     

Differentiation of Vitis vinifera L. and hybrid red grapes by matrix-assisted laser desorption/ionization mass spectrometry analysis of berry skin anthocyanins

Among the methods that have been developed for anthocyanin characterization, matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) offers several analytical advantages in terms of speed, minimal sample handling, specificity, and reliability, without requiring any previous chromatographic separation. This study used MALDI-TOF MS to profile the anthocyanins from the berry skins of 23 red grape varieties clustered as (i) authentic Vitis vinifera grapes, (ii) American hybrid cultivars, and (iii) Casavecchia cultivars, previously characterized as functional crosses of V. vinifera with nondefined hybrid grapevines. Anthocyanin profiling demonstrated evidence of several varietal traits that enabled the differentiation of authentic V. vinifera from hybrid cultivars on a molecular basis. In particular, acyl 3,5-O-diglucoside anthocyanins were established as easily monitored molecular markers of the hybrid varieties. It was also demonstrated that MALDI-post source decay MS is a powerful tool to differentiate isobaric 3,5-O-diglucosides and their derivatives, which prevail in hybrid cultivars, from acylated 3-O-glucoside anthocyanins.     

Effects of cadmium on growth and pharmacologically active constituents of the medicinal plant Coriandrum sativum L.

The effects of high levels of cadmium in soil and in the atmosphere on the plants of Coriandrum sativum L. (Umbellifereae) were investigated. Plants grown in contaminated soil (0, 10, 100 ppm of cadmium) showed a significant reduction in the length of the stems and roots and the number of the umbels, a yellowing and ultrastructural alterations of the leaves and a significant decrease in the essential oil composition. Similar effects were observed in the plants exposed to a simulated atmospheric pollution (plants were sprayed with CdCl₂ solutions containing Cd 0, 10, 100 mg/L). The effects are related to a degree of environmental contamination.     

Antioxidant effectiveness as influenced by phenolic content of fresh orange juices.

Several fresh orange juices, obtained from five different Citrus sinensis (L.) Osbeck varieties (three pigmented varieties, Moro, Sanguinello, and Tarocco, and two blond varieties, Valencia late and Washington navel), were subjected to antioxidant profile determination (including total polyphenols, flavanones, anthocyanins, hydroxycinnamic acids, and ascorbic acid). The antioxidant activity of these juices was then assessed by means of different "in vitro" tests (bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical; peroxidation, induced by the water-soluble radical initiator 2,2'-azobis(2-amidinopropane) hydrochloride, on mixed dipalmitoylphosphatidylcholine/linoleic acid unilamellar vesicles; scavenging activity against nitric oxide; total antioxidant status). All orange juices tested showed an evident antioxidant effect. Our findings indicate the following: (1) the antioxidant efficiency of orange juices may be attributed, in a significant part at least, to their content of total phenols, (2) while ascorbic acid seems to play a minor role; (3) the antioxidant activity of orange juices is related not only to structural features of phytochemicals contained in them, but also to their capability to interact with biomembranes; (4) finally, as to pigmented juices, their antioxidant efficiency appears to be widely influenced by the anthocyanin level. One could speculate that the supply of natural antioxidant phenols through daily consumption of orange juice might provide additional protection against in vivo oxidation of cellular biomolecules.