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[Display omitted] • Agronomic quality of digestate was improved by adding Agricultural Jiaosu (AJ). • Adding AJ reducing free ammonia of digestate helps to reduce the phytotoxicity. • The abundance of some agricultural beneficial genera was increased by adding AJ. • We revealed links between chemical, plant, and microbial indicators in digestate. Anaerobic digestate disposal is challenging, hampering the development of large-scale biogas projects. Currently, digestate is primarily stabilized naturally and subsequently applied to farmland. However, during this process, the number of beneficial microorganisms decreases, free ammonia nitrogen increases, and pH rises, decreasing the benefits of digestate to soil and plants. In this study, digestate was treated by adding agricultural Jiaosu (AJ). The agronomic quality of the digestate was explored by conducting a pot experiment. Subsequently, the mechanisms of the changes in digestate properties were investigated based on chemical and microbial parameters. The results showed that the digestate with a 10% AJ supplement significantly improved the plant characteristics such as plant height, fresh weight, and leaf area. Regarding chemical properties, the addition of 10% AJ decreased the total ammonia nitrogen and free ammonia nitrogen in the digestate to below the toxicity threshold. With respect to microorganisms, the addition of AJ improved the microbial diversity of the digestate and increased the relative abundances of Advenella , Trichococcus, and Comamonas spp., which are beneficial to both soil and plants. Moreover, AJ decreased the abundance of potentially threatening microorganisms such as Thiopseudomonas and Papillibacter spp. Collaborative analysis showed that the improvement in digestate agronomic quality was closely related to its effects on microorganisms. Based on these results, the present study suggests an approach to the post-treatment of anaerobic digestate that can improve its fertilizer value while reducing its phytotoxicity. Furthermore, this study provides a model for a more comprehensive evaluation of the agronomic quality of digestate. [ABSTRACT FROM AUTHOR]

A cascadic sensing system was developed for detection of DNA target at ultralow concentration by a combination of magnetic nanoparticles (MNPs) and exonuclease III (Exo III)-induced cascade two-stage isothermal amplification in the study. An ingeniously designed capture hairpin probe (CHP) that integrates target-binding and signal transduction sequences within one multifunctional design was assembled on MNPs. Upon sensing of the analyte nucleic acid, the hairpin probe on MNPs could be opened and stepwise removed by Exo III accompanied by the releasing of target DNA for the successive hybridization and cleavage process and the generation of bare signal transduction sequences of CHP as a new trigger for next circular reaction. The new DNA triggers initiate hybridizing with hairpin DNA probe that contains a partially "caged" G-quadruplex sequence (GHP), forming a duplex structure and liberating the active G-quadruplex structure. Then, Exo III digests the resulting duplex domain, leading to the recycling of new DNA trigger and simultaneously generating numerous ZnPPIX/G-quadruplex supramolecular complexes with the help of the zinc (II)-protoporphyrin IX (ZnPPIX), as an optical label for amplified fluorescence sensing event. Finally, numerous liberated cascade ZnPPIX/G-quadruplex supramolecular complexes give a remarkable fluorescence response. Because of two-stage autocatalytic recycling amplification and the specifically catalyzed formation of ZnPPIX/G-quadruplex supramolecular complexes, this newly designed protocol provides a high sensitivity with a detection limit of 0.75 fM, can discriminate mismatched DNA from perfectly matched target DNA, and gives low matrix effect due to using MNPs as the separation and amplification elements in the real samples. Therefore, it holds great potential for early diagnosis in gene-related diseases. [ABSTRACT FROM AUTHOR]