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Sooty mold is a plant disease caused by Aleurocanthus spiniferus, an alien insect spread widely in the South of Puglia region (Italy) that causes extensive damage to citrus crops. Sooty mold is a complex disease: the insect sucks the sap of the plant and expels a sugary liquid called honeydew which supports the growth of a black biofilm on the plant. This biofilm is made up of various types of fungi and, while not causing disease, it contributes to plant malaise by inhibiting photosynthesis. In this study, microbiological and chemical methods have been used to characterize two bacterial strains, Bacillus velezensis MT9 and Pseudomonas chlororaphis MT5, which were isolated from soil samples taken from vine-cultivated land and can be used as biocontrol agents (BCA). These bacteria were shown to produce antibacterial and antifungal activities in the form of water-soluble molecules and were effective in vitro in inhibiting the growth of two fungal strains, Penicillium sp. YM1 and YM2, isolated from citrus soot. In addition to water-soluble molecules, P. chlororaphis MT5 was shown to produce antifungal volatile organic compounds (VOCs). The VOCs produced by B. velezensis MT9 and P. chlororaphis MT5 were then identified by gas chromatography – mass spectrometry (GC–MS). Interestingly, some of the identified VOCs have previously been reported to have semiochemical activity in insects and, therefore, can interfere with chemical signaling in plant-insect-microbe interaction. Altogether these in vitro findings and pilot experiments with a limited set of plants indicate that Bacillus velezensis MT9 and Pseudomonas chlororaphis MT5 can effectively combat sooty mold possibly by acting on both the insects and the fungi that inhabit the black biofilm, paving the way for an innovative and sustainable tool to fight this disease.

Background: Non-occupational cases of contact dermatitis to finished wood are occasionally reported from contact with wooden jewellery, musical instruments, knife handles and wooden footwear. Two female patients, 26 and 34 years old, developed acute eczema on the wrists after they worn in the summer a kind of catholic bracelet called “memorabilia” made by single wooden chunks with over-impressed iconic religious images. Objectives: To identify the culprit photoallergen responsible for the reported adverse reactions suspected to be a compound of the wooden bracelets. Methods: Three months after the resolution of the dermatitis, patch test and photo-patch tests were performed with the S.I.D.A.P.A. (Italian Society of Allergic, Occupational and Environmental Dermatology) standard series, and with wood sawdust obtained from both bracelets and tested at 5% in pet. A thin-layer chromatogram (TLC) strip and an extract made from the bracelets were tested in both the patients as patch test and photo-patch test. The extracts of the wooden bracelets were analyzed by gas chromatography – mass spectrometry (GC-MS). Results: Patch tests and photo-patch test with standard series turned out negative. Photo-patch tests with wood sawdust in pet. 5% evidenced a positive reaction (++) in both patients. Two chemicals were detected in the wooden bracelets with GC-MS: dibutylphthalate, commonly used as plasticizer, and 8,8-dimethyl-2H,8H-benzo[1,2-b:3,4-b']dipyran-2-one, a coumarin. Patch test with TLC did not elicit positive reactions but the photo-patch test with TLC gave positive reactions in both the patients to the same invisible spot on the strips. Two coumarins (8,8-dimethyl-2H,8H-benzo[1,2-b:3,4-b']dipyran-2-one and 8,8-dimethyl-2H,8H-benzo[1,2-b:5,4-b']dipyran-2-one) were detected in the spot with GC-MS. Conclusion: Coumarins are chemicals found in many plants with a known photo-allergic potential. They are probably the main photo-allergens in religious wooden bracelets instead of quinones and psoralens hypothesized in previous reports.

Introduction Xylella fastidiosa (Xf) is a pathogenic bacterium that causes diseases in olive trees. Therefore, analytical methods for both the characterisation of the host/pathogen interaction and infection monitoring are needed. Volatile organic compounds (VOCs) are emitted by plants relate to their physiological state, therefore VOCs monitoring can assist in detecting stress or infection states before visible signs are present. Objective In this work, the headspace-solid phase microextraction-gaschromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the first time to highlight VOCs differences between healthy and Xf-infected olive trees. Methodology VOCs from olive tree twig samples were extracted and analysed by HS-SPME-GC-MS, and hence identified by comparing the experimental linear retention indexes with the reference values and by MS data obtained from NIST library. Data were processed by principal component analysis (PCA) and analysis of variance (ANOVA). Results The HS-SPME step was optimised in terms of adsorbent phase and extraction time. HS-SPME-GC-MS technique was applied to the extraction and analysis of VOCs of healthy and Xf-infected olive trees. More than 100 compounds were identified and the differences between samples were evidenced by the multivariate analysis approach. The results showed the marked presence of methyl esters in Xf-infected samples, suggesting their probable involvement in the mechanism of diffusible signal factor. Conclusion The proposed approach represents an easy and solvent-free method to evaluate the presence of Xf in olive trees, and to evidence volatiles produced by host/pathogen interactions that could be involved in the defensive mechanism of the olive tree and/or in the infective action of Xf.

Concentrated Growth Factors (CGF) represent new autologous (blood-derived biomaterial), attracting growing interest in the field of regenerative medicine. In this study, the chemical, structural, and biological characterization of CGF was carried out. CGF molecular characterization was performed by GC/MS to quantify small metabolites and by ELISA to measure growth factors and matrix metalloproteinases (MMPs) release, structural CGF characterization was carried out by SEM analysis and immunohistochemistry, CGF has been cultured, and its primary cells were isolated for the identification of their surface markers by flow cytometry, Western blot, and real-time PCR, finally, the osteogenic differentiation of CGF primary cells was evaluated through matrix mineralization by alizarin red staining and through mRNA quantification of osteogenic differentiation markers by real-time PCR. We found that CGF has a complex inner structure capable of influencing the release of growth factors, metabolites, and cells. These cells, which could regulate the production and release of the CGF growth factors, show stem features and are able to differentiate into osteoblasts producing a mineralized matrix. These data, taken together, highlight interesting new perspectives for the use of CGF in regenerative medicine.

Comparison of fine and coarse fractions in terms of sources and dynamics is scarce in southeast Mediterranean countries; differences are relevant because of the importance of natural sources like sea spray and Saharan dust advection, because most of the monitoring networks are limited to PM10. In this work, the main seasonal variabilities of sources and processes involving fine and coarse PM (particulate matter) were studied at the Environmental-Climate Observatory of Lecce (Southern Italy). Simultaneous PM2.5 and PM10 samples were collected between July 2013 and July 2014 and chemically analysed to determine concentrations of several species: OC (organic carbon) and EC (elemental carbon) via thermo-optical analysis, 9 major ions via IC, and 23 metals via ICP-MS. Data was processed through mass closure analysis and Positive Matrix Factorization (PMF) receptor model characterizing seasonal variabilities of nine sources contributions. Organic and inorganic secondary aerosol accounts for 43% of PM2.5 and 12% of PM2.5–10 with small seasonal changes. SIA (secondary inorganic aerosol) seasonal pattern is opposite to that of SOC (secondary organic carbon). SOC is larger during the cold period, sulphate (the major contributor to SIA) is larger during summer. Two forms of nitrate were identified: NaNO3, correlated with chloride depletion and aging of sea-spray, mainly present in PM2.5–10; NH4NO3 more abundant in PM2.5. Biomass burning is a relevant source with larger contribution during autumn and winter because of the influence of domestic heating, however, is not negligible in spring and summer, because of the contributions of fires and agricultural practices. Mass closure analysis and PMF results identify two soil sources: crustal associated to long range transport and carbonates associated to local resuspended dust. Both sources contributes to the coarse fraction and have different dynamics with crustal source contributing mainly in high winds from SE conditions and carbonates during high winds from North direction.

While in recent years the key role of non-coding RNAs (ncRNAs) in the regulation of gene expression has become increasingly evident, their interaction with the global regulatory circuits is still obscure. Here we analyzed the structure and organization of the transcriptome of Streptomyces ambofaciens, the producer of spiramycin. We identified ncRNAs including 45 small-RNAs (sRNAs) and 119 antisense-RNAs (asRNAs I) that appear transcribed from dedicated promoters. Some sRNAs and asRNAs are unprecedented in Streptomyces and were predicted to target mRNAs encoding proteins involved in transcription, translation, ribosomal structure and biogenesis, and regulation of morphological and biochemical differentiation. We then compared ncRNA expression in three strains: (i) the wild-type strain, (ii) an isogenic pirA-defective mutant with central carbon metabolism imbalance, “relaxed” phenotype, and repression of antibiotic production, and (iii) a pirA-derivative strain harboring a “stringent” RNA polymerase that suppresses pirA-associated phenotypes. Data indicated that the expression of most ncRNAs was correlated to the stringent/relaxed phenotype suggesting novel effector mechanisms of the stringent response.

International audience; In the marine context, information about dispersal is essential for the design of networks of marine protected areas (MPAs). Generally, most of the dispersal of demersal fishes is thought to be driven by the transport of eggs and larvae in currents, with the potential contribution of dispersal in later life stages relatively minimal.Using otolith chemistry analyses, we estimate dispersal patterns across a spatial scale of approximately 180 km at both propagule (i.e. eggs and larvae) and juvenile (i.e. between settlement and recruitment) stages of a Mediterranean coastal fishery species, the two-banded seabream Diplodus vulgaris. We detected three major natal sources of propagules replenishing local populations in the entire study area, suggesting that propagule dispersal distance extends to at least 90 km. For the juvenile stage, we detected dispersal of up to 165 km. Our work highlights the surprising and significant role of dispersal during the juvenile life stages as an important mechanism connecting populations. Such new insights are crucial for creating effective management strategies (e.g. MPAs and MPA networks) and to gain support from policymakers and stakeholders, highlighting that MPA benefits can extend well beyond MPA borders, and not only via dispersal of eggs and larvae, but also through movement by juveniles.