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Chitin (Ct) is a crucial biopolymer present in fungi, algae, arthropods, and is usually obtained from crustacean shells. Chitosan (Cs) is a derivative from Ct deacetylation, and possesses numerous uses in various agro-industrial fields. Research on fungal-derived Ct and Cs is mostly focused on pharmaceutical uses, however their uses for plant disease control remain less explored. The main objective of the current study is to evaluate the possibility of using chitosan obtained from mushroom Pleurotus eryngii (Cs-Pe) for controlling some phytopathogens compared to commercial chitosan (C.Cs). This study is focused on the following key areas: (i) extracting Ct from P. eryngii mycelium and converting it to Cs through deacetylation, using both bleaching and non-bleaching methods; (ii) conducting a physico-chemical characterization and in vitro evaluation of the antimicrobial activity of the obtained Cs; (iii) performing an in vivo assessment of the phytotoxic and cytotoxic effects of Cs; and (iv) investigating in vivo the impact of the studied chitosan on fruit quality and its biocontrol efficacy against Monilinia laxa infections in plum fruits. Results showed that Cs-Pe, especially the unbleached one, displayed promising in vitro antimicrobial activity against the majority of tested pathogens. Regarding the cytotoxicity, the highest significant increase in cell abnormality percentage was observed in the case of C.Cs compared to Cs-Pe. In the in vivo study, Cs-Pe acted as a protective barrier, lowering and/or preventing moisture loss and firmness of treated plums. The studied Cs-Pe demonstrated notable efficacy against M. laxa which decreased the fruits' percentage decline. These results strongly suggest that Cs derived from P. eryngii is a potential candidate for increasing plums' shelf-life. This research shed light on the promising applications of P. eryngii-derived Cs in the agri-food field. [ABSTRACT FROM AUTHOR]

The Middle Eastern prevalence of sickle cell anemia, a genetic disorder that affects red blood cells, necessitates additional research. On a molecular level, we sought to identify and sort the oral microbiota of healthy individuals and those with sickle cell anemia. Furthermore, it is crucial to comprehend how changes in the genetic makeup of the oral microbiota impact the state of sickle cell anemia. Using next-generation sequencing, the 16S rRNA amplicon was examined using saliva samples from 36 individuals with sickle cell anemia and healthy individuals. These samples were obtained from sickle cell anemia patients (18 samples) and healthy control participants (controls, 18 samples). Various analyses are conducted using bioinformatic techniques to identify distinct species and their relative abundance. Streptococcus, followed by Fusobacterium nucleatum, Prevotella, and Veillonella were the most prevalent genera of bacteria in the saliva of the SCA and non-SCA individuals according to our findings. Rothia mucilaginosa, Prevotella scoposa, and Veillonella dispar species were the dominant species in both sickle cell anemia and non-sickle cell anemia subjects. Streptococcus salivarius, Actinomyces graevenitzii, Actinomyces odontolyticus, and Actinomyces georgiae spp. were the most prevalent bacterial spp. in the studied SCA cases. The sequencing of the 16S rRNA gene yielded relative abundance values that were visualized through a heatmap analysis. Alterations in the oral microflora's constitution can significantly affect the susceptibility of sickle cell anemia patients to develop more severe health complications. Salivary diagnosis is a potential tool for predicting and preventing oral microbiome-related diseases in the future. [ABSTRACT FROM AUTHOR]

Kiwifruit vine decline syndrome (KVDS) is an emerging challenge related to various factors, including water stagnation, soil compaction, root hypoxia, imbalanced soil redox potential, soil nutrient imbalance and fungal pathogens, yet its definitive causes remain unconfirmed. This study compared soils and roots of healthy plants (CTRL group) and plants affected by KVDS (KVDS group) at a kiwifruit orchard (Actinidia chinensis cv. 'Zesy002') in Sermoneta (Lazio region), Italy. Our findings indicate that soil redox potential, a parameter related to soil oxidation, and soil macroporosity were significantly lower in the KVDS soils. The water table was also found to be higher in the KVDS block of the orchard, demonstrating a higher soil water content. This suggests less aeration and more water content in KVDS‐affected soils compared to the control. Root analyses showed that KVDS led to browning and decomposition of rhizodermis, decay of the central stele, detachment of the cortex, reduced cell size and the presence of starch granules in the parenchyma, with significant variations in root morphometric parameters. To mitigate KVDS, sustainable agronomic practices, including precision irrigation, green manure, compost addition and water drainage root pruning, were carried out on some KVDS‐symptomatic vines (SUST group). Molecular analyses revealed the presence of 10 fungal species from treated root plants, with Paraphaeosphaeria michotii, Fusarium oxysporum and Ilyonectria vredenhoekensis being frequently isolated from symptomatic KVDS‐affected plants but less from SUST plants. Also, Beauveria bassiana and Bacillus amyloliquefaciens, showed an effect against I. vredenhoekensis and P. michotii, and may be suitable candidates as biocontrol agents. The adoption of sustainable agronomic practices resulted in significantly more healthy plants (46% increase) by the end of the trial, demonstrating that a sustainable soil use and water management at kiwifruit orchards can mitigate KVDS through restoration of natural growth conditions. [ABSTRACT FROM AUTHOR]