pH-Responsive On-Demand Alkaloids Release from Core–Shell ZnO@ZIF-8 Nanosphere for Synergistic Control of Bacterial Wilt Disease

Abstract

Developing an effective and safe technology to control severe bacterial diseases in agriculture has attracted significant attention. Here, ZnO nanosphere and ZIF-8 are employed as core and shell, respectively, and then a pH-responsive core–shell nanocarrier (ZnO-Z) was prepared by in situ crystal growth strategy. The bactericide berberine (Ber) was further loaded to form Ber-loaded ZnO-Z (Ber@ZnO-Z) for control of tomato bacterial wilt disease. Results demonstrated that Ber@ZnO-Z could release Ber rapidly in an acidic environment, which corresponded to the pH of the soil where the tomato bacterial wilt disease often outbreak. In vitro experiments showed that the antibacterial activity of Ber@ZnO-Z was about 4.5 times and 1.8 times higher than that of Ber and ZnO-Z, respectively. It was because Ber@ZnO-Z could induce ROS generation, resulting in DNA damage, cytoplasm leakage, and membrane permeability changes so the released Ber without penetrability more easily penetrated the bacteria to achieve an efficient synergistic bactericidal effect with ZnO-Z carriers after combining with DNA. Pot experiments also showed that Ber@ZnO-Z significantly reduced disease severity with a wilt index of 45.8% on day 14 after inoculation, compared to 94.4% for the commercial berberine aqueous solution. More importantly, ZnO-Z carriers did not accumulate in aboveground parts of plants and did not affect plant growth in a short period. This work provides guidance for the effective control of soil-borne bacterial diseases and the development of sustainable agriculture.

Zeolitic Imidazole Framework-90-Based Pesticide Smart-Delivery System with Enhanced Antimicrobial Performance

“…As shown in Figure 6 , the growth inhibition rates of Magnaporthe oryzae colony were affected by KSM aqueous solution and ZIF-90-KSM in a typical dose-dependent manner. These results are in agreement with those reported by other researchers for nano-fungicides [ 25 , 50 ]. The toxicity regression equations, EC 50 values, 95% confidence interval, and correlation coefficients ( r ) of the samples are listed in Table S3 .…”

Ultrasound-Activated, Tumor-Specific In Situ Synthesis of a Chemotherapeutic Agent Using ZIF-8 Nanoreactors for Precision Cancer Therapy

“…The as-prepared ZIF-8s had a cube-shaped morphology, as revealed by scanning (SEM) and transmission electron microscopy (TEM, Figure a), with a particle size of 201.1 ± 2.1 nm and a ζ potential value of 20.1 ± 0.5 mV, as measured by dynamic light scattering (DLS, n = 6 batches). The powder X-ray diffraction (PXRD) pattern of the experimentally prepared ZIF-8s closely matched the simulated data (Figure b) . The as-prepared ZIF-8s exhibited hollow cavities and high surface areas with a pore volume (analyzed by the t-plot method) and a specific surface area (analyzed by the Brunauer–Emmett–Teller, BET, method) of 0.86 cm 3 /g and 1832.4 m 2 /g, respectively, providing numerous spaces into which the precursors could be incorporated.…”

“…The powder X-ray diffraction (PXRD) pattern of the experimentally prepared ZIF-8s closely matched the simulated data (Figure 1b). 29 The as-prepared ZIF-8s exhibited hollow cavities and high surface areas with a pore volume (analyzed by the t-plot method) 30 and a specific surface area (analyzed by the Brunauer−Emmett−Teller, BET, method) 31 of 0.86 cm 3 /g and 1832.4 m 2 /g, respectively, providing numerous spaces into which the precursors could be incorporated. ZIF-8s have attracted considerable attention owing to their adsorption capacity and consequent ability to carry hydrophilic, hydrophobic, and amphiphilic substances.…”

Polyethyleneimine coated MXene quantum dots improve cotton tolerance to Verticillium dahliae by maintaining ROS homeostasis

“…For example, CeO2 nanoparticles modulate Cu-Zn superoxide dismutase and lipoxygenase-IV isozyme activities to alleviate membrane oxidative damage to improve rapeseed salt tolerance 36 . Zinc oxide nanospheres significantly reduce the severity of bacterial wilt and increase plant biomass and antioxidant enzyme content in tomato 37 .…”

“…Studies have shown that some nanomaterials have the ability to simulate the activity of antioxidant enzymes, thus showing a good ability of scavenging ROS and have the ability to promote the germination and growth of plants and enhance plant resistance 36,37 . For example, CeO2 nanoparticles modulate Cu-Zn superoxide dismutase and lipoxygenase-IV isozyme activities to alleviate membrane oxidative damage to improve rapeseed salt tolerance 36 .…”