Does the Harvest Type Affect Olive Health? Influence of the Harvesting System and Storage Time on the Chemical, Volatile and Sensory Qualities of Extra Virgin Olive Oils.

With the aim of investigating the effect of bruising and its development during the postharvest time, olive fruits (Frantoio and Moraiolo), manually and mechanically harvested, were stored in climatic chambers at two different temperatures (5 °C and 18 °C) for five days. Visual observations highlighted changes in the olive peel with discoloration in the damaged areas and tissue bruising. Olive fruit polyphenols, volatile organic compounds (VOCs) and other oil quality parameters (phenolic content, free acidity and peroxide index) and sensory assessment were evaluated. Analyses were carried out on fruits and experimental extra virgin oils at harvesting and after 5 days of fruit storage. The results highlight that low-temperature storage (5 °C for 5 days) may contribute to the maintenance of high olive oil quality, and the quality of olives stored at room temperature drastically decreases after 5 days of storage. Moreover, mechanical harvesting, compared to manual harvesting, does not seem to affect the final oil quality, at least at harvesting, but seems to determine differences in the long-term storage period. Finally, the samples stored at 18 °C showed a quality deterioration with the development of sensorial defects.

Metabolomic Approach Based on Analytical Techniques for the Detection of Secondary Metabolites from Humulus lupulus L. Dried Leaves.

Currently, the leaves of the hop plant (Humulus lupulus L.) are an unexploited and still little-investigated agricultural by-product. In our study, with the aim of exploring the metabolome of dried hop leaves (Chinook cultivar), a metabolomic approach was applied using multiple analytical tools such as SPME/GC-MS, GC-MS, PTR-ToF-MS, and NMR to identify the secondary metabolites. The obtained results showed the presence of a high number of components belonging to different chemical classes. In fact, thanks to the multi-methodological approach, volatile organic compounds (VOCs) with low molecular weight, terpenic compounds, fatty acids, sugars, amino acids, organic acids, and alcohols have been detected and identified. Among the revealed terpenes in the untreated matrix, the sesquiterpenes α-humulene, ß-caryophyllene, and α-copaene were the most abundant. Among the saturated and unsaturated fatty acids, palmitic and linolenic acids, respectively, were those with the highest relative percentages. Particularly relevant was the sugar content, where sucrose was the main exponent while glutamate and asparagine were the principal detected amino acids. Conversely, alcohols and organic acids were the least abundant compound classes, and xanthohumol was also identified in the methanolic extract.

On the lookout for influenza viruses in Italy during the 2021-2022 season: Along came A(H3N2) viruses with a new phylogenetic makeup of their hemagglutinin.

AIMS: To assess influenza viruses (IVs) circulation and to evaluate A(H3N2) molecular evolution during the 2021-2022 season in Italy. MATERIALS AND METHODS: 12,393 respiratory specimens (nasopharyngeal swabs or broncho-alveolar lavages) collected from in/outpatients with influenza illness in the period spanning from January 1, 2022 (week 2022-01) to May 31, 2022 (week 2022-22) were analysed to identify IV genome and were molecularly characterized by 12 laboratories throughout Italy. A(H3N2) evolution was studied by conducting an in-depth phylogenetic analysis of the hemagglutinin (HA) gene sequences. The predicted vaccine efficacy (pVE) of vaccine strain against circulating A(H3N2) viruses was estimated using the sequence-based Pepitope model. RESULTS: The overall IV-positive rate was 7.2% (894/12,393), all were type A IVs. Almost all influenza A viruses (846/894; 94.6%) were H3N2 that circulated in Italy with a clear epidemic trend, with 10% positivity rate threshold crossed for six consecutive weeks from week 2022-11 to week 2022-16. According to the phylogenetic analysis of a subset of A(H3N2) strains (n=161), the study HA sequences were distributed into five different genetic clusters, all of them belonging to the clade 3C.2a, sub-clade 3C.2a1 and the genetic subgroup 3C.2a1b.2a.2. The selective pressure analysis of A(H3N2) sequences showed evidence of diversifying selection particularly in the amino acid position 156. The comparison between the predicted amino acid sequence of the 2021-2022 vaccine strain (A/Cambodia/e0826360/2020) and the study strains revealed 65 mutations in 59 HA amino acid positions, including the substitution H156S and Y159N in antigenic site B, within major antigenic sites adjacent to the receptor-binding site, suggesting the presence of drifted strains. According to the sequence-based Pepitope model, antigenic site B was the dominant antigenic site and the p(VE) against circulating A(H3N2) viruses was estimated to be -28.9%. DISCUSSION AND CONCLUSION: After a long period of very low IV activity since public health control measures have been introduced to face COVID-19 pandemic, along came A(H3N2) with a new phylogenetic makeup. Although the delayed 2021-2022 influenza season in Italy was characterized by a significant reduction of the width of the epidemic curve and in the intensity of the influenza activity compared to historical data, a marked genetic diversity of the HA of circulating A(H3N2) strains was observed. The identification of the H156S and Y159N substitutions within the main antigenic sites of most HA sequences also suggested the circulation of drifted variants with respect to the 2021-2022 vaccine strain. Molecular surveillance plays a critical role in the influenza surveillance architecture and it has to be strengthened also at local level to timely assess vaccine effectiveness and detect novel strains with potential impact on public health.

SPME-GC-MS and PTR-ToF-MS Techniques for the Profiling of the Metabolomic Pattern of VOCs and GC-MS for the Determination of the Cannabinoid Content of Three Cultivars of Cannabis sativa L. Pollen.

Considering the large number of volatile molecules that characterize Cannabis sativa L., adequate investigation supported by the application of robust and effective analytical methods is essential to better understand the impact of these low- and medium-molecular-weight molecules on the entire phytocomplex. This work aimed to characterize the volatile fraction of the chemical profile of three different cultivars of Cannabis sativa L. pollen, grown in Italy, which were thoroughly investigated by the application of two complementary techniques: SPME-GC-MS and PTR-ToF-MS. Furthermore, in order to provide more information on the chemical profile of the matrices under study, the cannabinoid content of the hexane extracts was also measured by GC-MS. Until now, no similar study, in terms of survey techniques applied, has been performed on C. sativa pollen. The obtained results showed a high content of volatile molecules, which differentiated the three matrices. The data relating to the content of cannabinoids were also interesting as they showed that one of the three cultivars was richer than the others. Finally, an in-depth statistical survey was performed to better compare the investigated samples and identify the molecules that most contribute to differentiating them. The findings of this study may be useful for integrating the compositional information on C. sativa L.

SARS-CoV-2 variants of concern surveillance including Omicron using RT-PCR-based genotyping offers comparable performance to whole genome sequencing.

Known SARS-CoV-2 variants of concern (VOCs) can be detected and differentiated using an RT-PCR-based genotyping approach, which offers quicker time to result, lower cost, higher flexibility, and use of the same laboratory instrumentation for detection of SARS-CoV-2 when compared with whole genome sequencing (WGS). In the current study, we demonstrate how we applied a genotyping approach for identification of all VOCs and that such technique can offer comparable performance to WGS for identification of known SARS-CoV-2 VOCs, including more recent strains, Omicron BA.1 and BA.2.

Hops Germplasm: Phytochemical Characterization of Wild Humulus lupulus of Central and Northern Italy.

Hops are widespread as a wild plant in almost all Northern and Central Italy, and the characterization of wild populations is attracting considerable interest in verifying their potential use. The development of hops as agricultural crop can be an interesting opportunity, both for farms that would have available a new crop to be included in the crop system and for craft breweries interested in characterizing beers with local raw materials. In the present work, 14 wild hop accessions coming from various Italian locations were characterized and compared with 2 commercial varieties (Cascade and Hallertau Taurus) grown in the same environments. The cones were analyzed to measure the content of α- and ß-acids, polyphenols, flavonoids, and the anti-radical power. The α-acid content of wild hops was generally low, while the ß-acid content was very variable and quite high in some samples. The content in polyphenols and flavonoids and the antiradical power were high and generally similar to those of the commercial varieties. Therefore, the analyzed genotypes are not very suitable for use as bitter hops in beer production, while further analysis may indicate a possible use as aroma hops, or for herbal and pharmaceutical purposes, thanks to their antioxidant content.

Survey of diagnostic and typing capacity for enterovirus infection in Italy and identification of two echovirus 30 outbreaks.

BACKGROUND: Enterovirus infections can cause a variety of illnesses, ranging from asymptomatic infections to severe illness and death. AIM: To support polio eradication activities, in February 2019, the WHO Regional Reference Laboratory for polio in Italy, at the National Institute of Public Health (Istituto Superiore di Sanità), promoted an investigation on non-polio enterovirus laboratory capacity, with the support of the Italian Ministry of Health. The aim was to collect data on the assays used routinely for diagnostic purposes and to characterize enterovirus outbreaks strains by sequence analysis of the Viral Protein 1 region. METHODS: A questionnaire was administered to public health laboratories through all Italian Regions for 2018 and subsequently, an electronic form for lab-confirmed enterovirus infection reported from February 2019 to January 2020, including patients clinical characteristics, and laboratory data was distributed through 25 laboratories participating the survey. RESULTS: Overall, a homogenous laboratory capacity for enterovirus infection diagnosis was found and 21,000 diagnostic tests were retrospectively reported in 2018. Then, in 2019, two outbreaks of Echovirus 30 were identified and confirmed by molecular analyses. CONCLUSION: These results underline the need monitor the circulation of non-polio enterovirus to ascertain the real burden of the disease in the country.

Occurrence of two Norovirus outbreaks in the same cafeteria in one week.

In October 2017, two outbreaks of gastroenteritis (GE) occurred among patrons of a cafeteria in Italy in one week. Virological and bacteria investigations on stool samples, environment and food were conducted to identify the infectious agents and the possible source of infection. Forty-five cases occurred in the two outbreaks, including 13 laboratory-confirmed cases of norovirus GI. Nine staff members were interviewed, six were confirmed positive for NoV GI and 3 experienced GE symptoms. Bacteria faecal indicators and other bacteria pathogens were not detected in either environmental swab samples or food. A low level of NoV GII was detected in two environmental swab samples. The same GI.6 strain was identified in cases related to both outbreaks, suggesting a common source of infection. Since the two outbreaks occurred in one week, the NoV contamination could have persisted in the cafeteria. Furthermore, virological investigation revealed confirmed cases among food handlers who had worked at the cafeteria between and during the two outbreaks. Several studies highlighted the importance of excluding symptomatic food handlers to prevent contamination of foods and environment.

Root phonotropism: Early signalling events following sound perception in Arabidopsis roots.

Sound is a fundamental form of energy and it has been suggested that plants can make use of acoustic cues to obtain information regarding their environments and alter and fine-tune their growth and development. Despite an increasing body of evidence indicating that it can influence plant growth and physiology, many questions concerning the effect of sound waves on plant growth and the underlying signalling mechanisms remains unknown. Here we show that in Arabidopsis thaliana, exposure to sound waves (200Hz) for 2 weeks induced positive phonotropism in roots, which grew towards to sound source. We found that sound waves triggered very quickly (within minutes) an increase in cytosolic Ca2+, possibly mediated by an influx through plasma membrane and a release from internal stock. Sound waves likewise elicited rapid reactive oxygen species (ROS) production and K+ efflux. Taken together these results suggest that changes in ion fluxes (Ca2+ and K+) and an increase in superoxide production are involved in sound perception in plants, as previously established in animals.

The network of plants volatile organic compounds.

Plants emission of Volatile Organic Compounds (VOCs) is involved in a wide class of ecological functions, as VOCs play a crucial role in plants interactions with biotic and abiotic factors. Accordingly, they vary widely across species and underpin differences in ecological strategy. In this paper, VOCs spontaneously emitted by 109 plant species (belonging to 56 different families) have been qualitatively and quantitatively analysed in order to provide an alternative classification of plants species. In particular, by using bipartite networks methodology from Complex Network Theory, and through the application of community detection algorithms, we show that is possible to classify species according to chemical classes such as terpenes and sulfur compounds. Such complex network analysis allows to uncover hidden plants relationships related to their evolutionary and adaptation to the environment story.

Sensory, spectrometric (PTR-ToF-MS) and chemometric analyses to distinguish extra virgin from virgin olive oils.

Olive oil samples were obtained from six cultivars grown in different environments, and graded by chemical analyses as extra virgin (EVOOs). These were evaluated for flavors and off-flavors, and relative VOCs spectrum as determined by PTR-ToF-MS. A hierarchical clustering of Panel test data separated olive oil in three groups, one including the samples with perceived off-flavor (VOOs), regardless of cultivar and environment. The Pearson's correlation coefficients between the mass data from PTR-ToF-MS and the sensory characteristics perceived by the Panel test were determined. A mass-to-sensory attributes correlation index was calculated. A color-coded card was built up based on the intensities (ncps) of five selected protonated mass data that was able to distinguish EVOOs from VOOs olive oil samples.

Plant shoots exhibit synchronized oscillatory motions.

In animals, the ability to move has evolved as an important means of protection from predators and for enhancing nutrient uptake. In the animal kingdom, an individual's movements may become coordinated with those of other individuals that belong to the same group, which leads, for example, to the beautiful collective patterns that are observed in flocks of birds and schools of fish or in animal migration. Land plants, however, are fixed to the ground, which limits their movement and, apparently, their interactions and collective behaviors. We show that emergent maize plants grown in a group exhibit synchronized oscillatory motions that may be in-phase or anti-phase. These oscillations occur in short bursts and appear when the leaves rupture from the coleoptile tip. The appearance of these oscillations indicates an abrupt increase in the plant growth rate, which may be associated with a sudden change in the energy uptake for photosynthesis. Our results suggest that plant shoots behave as a complex network of biological oscillators, interacting through biophysical links, e.g. chemical substances or electric signals.

Networks of plants: how to measure similarity in vegetable species.

Despite the common misconception of nearly static organisms, plants do interact continuously with the environment and with each other. It is fair to assume that during their evolution they developed particular features to overcome similar problems and to exploit possibilities from environment. In this paper we introduce various quantitative measures based on recent advancements in complex network theory that allow to measure the effective similarities of various species. By using this approach on the similarity in fruit-typology ecological traits we obtain a clear plant classification in a way similar to traditional taxonomic classification. This result is not trivial, since a similar analysis done on the basis of diaspore morphological properties do not provide any clear parameter to classify plants species. Complex network theory can then be used in order to determine which feature amongst many can be used to distinguish scope and possibly evolution of plants. Future uses of this approach range from functional classification to quantitative determination of plant communities in nature.

Resting electrical network activity in traps of the aquatic carnivorous plants of the genera Aldrovanda and Utricularia.

In this study the MEA (multielectrode array) system was used to record electrical responses of intact and halved traps, and other trap-free tissues of two aquatic carnivorous plants, Aldrovanda vesiculosa and Utricularia reflexa. They exhibit rapid trap movements and their traps contain numerous glands. Spontaneous generation of spikes with quite uniform shape, propagating across the recording area, has been observed for all types of sample. In the analysis of the electrical network, higher richer synchronous activity was observed relative to other plant species and organs previously described in the literature: indeed, the time intervals between the synchronized clusters (the inter-spike intervals) create organized patterns and the propagation times vary non-linearly with the distance due to this synchronization. Interestingly, more complex electrical activity was found in traps than in trap-free organs, supporting the hypothesis that the nature of the electrical activity may reflect the anatomical and functional complexity of different organs. Finally, the electrical activity of functionally different traps of Aldrovanda (snapping traps) and Utricularia (suction traps) was compared and some differences in the features of signal propagation were found. According to these results, a possible use of the MEA system for the study of different trap closure mechanisms is proposed.

The electrical network of maize root apex is gravity dependent.

Investigations carried out on maize roots under microgravity and hypergravity revealed that gravity conditions have strong effects on the network of plant electrical activity. Both the duration of action potentials (APs) and their propagation velocities were significantly affected by gravity. Similarly to what was reported for animals, increased gravity forces speed-up APs and enhance synchronized electrical events also in plants. The root apex transition zone emerges as the most active, as well as the most sensitive, root region in this respect.

Exploring strategies for classification of external stimuli using statistical features of the plant electrical response.

Plants sense their environment by producing electrical signals which in essence represent changes in underlying physiological processes. These electrical signals, when monitored, show both stochastic and deterministic dynamics. In this paper, we compute 11 statistical features from the raw non-stationary plant electrical signal time series to classify the stimulus applied (causing the electrical signal). By using different discriminant analysis-based classification techniques, we successfully establish that there is enough information in the raw electrical signal to classify the stimuli. In the process, we also propose two standard features which consistently give good classification results for three types of stimuli--sodium chloride (NaCl), sulfuric acid (H2SO4) and ozone (O3). This may facilitate reduction in the complexity involved in computing all the features for online classification of similar external stimuli in future.

PTR-TOF-MS analysis of volatile compounds in olive fruits.

BACKGROUND: Volatile compounds of Cellina di Nardò and Ogliarola Barese, two typical Italian olive varieties, have been characterised at different ripening stages. Proton transfer reaction-time-of-flight-mass spectrometry (PTR-TOF-MS) was used for the first time on these fruits with the aim of characterising the volatile profile and, in the case of Ogliarola, the changes which may occur during the maturation process. RESULTS: PTR-TOF-MS does not involve any sample pre-treatment, and allows high-resolution measurements, large spectra and small fragmentation of the volatiles. Therefore it allows both compound identification and data statistical treatments. In the present work, about 40 compounds that contribute to the discrimination between samples of the two varieties have been identified. CONCLUSIONS: Three groups of compounds were identified: (1) compounds that are typical of mature fruits of Ogliarola, (2) compounds that tend to decrease during the change from green to mature fruits, and (3) compounds that increase during the maturation process.

Electrical spiking in bacterial biofilms.

In nature, biofilms are the most common form of bacterial growth. In biofilms, bacteria display coordinated behaviour to perform specific functions. Here, we investigated electrical signalling as a possible driver in biofilm sociobiology. Using a multi-electrode array system that enables high spatio-temporal resolution, we studied the electrical activity in two biofilm-forming strains and one non-biofilm-forming strain. The action potential rates monitored during biofilm-forming bacterial growth exhibited a one-peak maximum with a long tail, corresponding to the highest biofilm development. This peak was not observed for the non-biofilm-forming strain, demonstrating that the intensity of the electrical activity was not linearly related to the bacterial density, but was instead correlated with biofilm formation. Results obtained indicate that the analysis of the spatio-temporal electrical activity of bacteria during biofilm formation can open a new frontier in the study of the emergence of collective microbial behaviour.

Root based responses account for Psidium guajava survival at high nickel concentration.

The presence of Psidium guajava in polluted environments has been reported in recent studies, suggesting that this species has a high tolerance to the metal stress. The present study aims at a physiological characterization of P. guajava response to high nickel (Ni) concentrations in the root-zone. Three hydroponic experiments were carried out to characterize the effects of toxic Ni concentrations on morphological and physiological parameters of P. guajava, focusing on Ni-induced damages at the root-level and root ion fluxes. With up to 300µM NiSO4 in the root-zone, plant growth was similar to that in control plants, whereas at concentrations higher than 1000µM NiSO4 there was a progressive decline in plant growth and leaf gas exchange parameters; this occurred despite, at all considered concentrations, plants limited Ni(2+) translocation to the shoot, therefore avoiding shoot Ni(2+) toxicity symptoms. Maintenance of plant growth with 300µM Ni(2+) was associated with the ability to retain K(+) in the roots meanwhile 1000 and 3000µM NiSO4 led to substantial K(+) losses. In this study, root responses mirror all plant performances suggesting a direct link between root functionality and Ni(2+) tolerance mechanisms and plant survival. Considering that Ni was mainly accumulated in the root system, the potential use of P. guajava for Ni(2+) phytoextraction in metal-polluted soils is limited; nevertheless, the observed physiological changes indicate a good Ni(2+) tolerance up to 300µM NiSO4 suggesting a potential role for the phytostabilization of polluted soils.