Photo‐Stimuli Smart Supramolecular Self‐Assembly of Azobenzene/β‐Cyclodextrin Inclusion Complex for Controlling Plant Bacterial Diseases

Abstract

Controllable and on‐demand delivery of supramolecular systems have received considerable attention in modern agricultural management, especially for managing intractable plant diseases. Here, an intelligent photoresponsive pesticide delivery system is reported based on β‐cyclodextrin (β‐CD) and azobenzene, which overcomes the resistance of phytopathogens caused by the irrational use of conventional pesticides. Antibacterial bioassays illustrated that designed azobenzene derivative 3a possesses the most efficient bioactivity with EC50 values of 0.52–25.31 µg mL−1 toward three typical phytopathogens. Moreover, the assembly of the supramolecular binary complex 3a@β‐CD is successfully elucidated and displays exceptional inhibitory activity on biofilm formation. Of note, this supramolecular binary complex significantly improves the water solubility, foliar surface wettability, and shows marked light‐responsive properties. In vivo anti‐Xoo assays reveal that 3a@β‐CD has excellent control efficiency (protective activity: 51.22%, curative activity: 48.37%) against rice bacterial blight pathogens, and their control efficiency can be elevated to values of 55.84% (protective activity) and 52.05% (curative activity) by UV–vis exposure. In addition, the 3a@β‐CD are non‐toxic toward various non‐target organisms. This study therefore offers new insights into the potential of host‐guest complexes as a feasible pesticide discovery strategy characterized by a safe, biocompatible, light‐responsive release, and antibiofilm properties for overcoming intractable plant bacterial diseases.

Discovery and Structural Optimization of 1,2,3,4-Tetrahydro-β-carbolines as Novel Reactive Oxygen Species Inducers for Controlling Intractable Plant Bacterial Diseases

“…All synthesized compounds were evaluated for their antibacterial activities against phytopathogenic bacteria using the turbidimetric test . Bioassay results (Table ) displayed that most of these novel THBC derivatives exhibited moderate to good inhibitory activities against Xoo , Xac , and Psa , with EC 50 values ranging from 2 to 50 μg/mL.…”

“…The potential application of our designed compounds for managing rice bacterial leaf blight was examined using the pot experiment. On the basis of in vitro bioassays, the most active compound I 29 (EC 50 = 5.73 μg/mL) was chosen to assess the efficacy test under a controlled environment. ,− The results showed that compound I 29 exhibited good protective activity for reducing rice bacterial leaf blight with a control efficiency of 55.74%, which was noticeably better than that of BT (28.69%) and TC (25.46%) (Figure and Table ). Interestingly, the control efficiency of compound I 29 was improved significantly when adding 0.5% adjuvants of organic silicon (SI) and orange peel essential oil (OPO), with the protective activity reaching 59.60 and 66.73%, respectively.…”

“…oryzae ( Xoo ), and Pseudomonas syringae pv. actinidiae ( Psa ), in vivo anti- Xoo bioassay, ROS detection assay, fluorescent imaging experiments, and enzyme activity bioassays were conducted according to our reported methods, with minor modifications. ,− For all of the experiments, the commercial bactericides thiodiazole copper (TC, 20% suspending agent) and bismerthiazol (BT, 90% technical material) were used as positive controls.…”

“…All synthesized compounds were evaluated for their antibacterial activities against phytopathogenic bacteria using the turbidimetric test. 41 Bioassay results (Table 1) displayed that most of these novel THBC derivatives exhibited moderate to good inhibitory activities against Xoo, Xac, and Psa, with EC 50 values ranging from 2 to 50 μg/mL. Notable, compounds I 2 −I 6 , I 9 − I 16 , and I 17 , decorated with different benzylamine, N-methylbenzylamine, and N-ethylbenzylamine groups, respectively, exhibited eminent antibacterial competence toward three tested bacteria strains, with the EC 50 values ranging from 2 to 20 μg/mL.…”

Temperature-Responsive Cocrystal Engineering for Efficacious Delivery of Poorly Water-Soluble Herbicide

“…To solve this problem, there are currently some solutions, such as introducing additives or adjuvants, , forming salts, , forming inclusion complexes, − but these solutions have the disadvantages of cumbersome operation and difficult amplification. Drawing on the widespread use of cocrystal engineering strategies in pharmacy to modulate active components, this important problem in agriculture may be addressed. , Different from traditional organic chemical synthesis, where the breaking and formation of chemical bonds between atoms or molecules plays a key role in the design of new compounds, the building blocks of cocrystal engineering are in a stoichiometric ratio through noncovalent intermolecular interactions, bonded in the unit cell .…”