2 research outputs found
Efficient Control of Rhizoctonia solani Using Environmentally Friendly pH-Responsive Tannic Acid–Rosin Nano-Microcapsules
A nanomicrocapsule system was constructed
through the
polymerization
of tannic acid (TA) and emulsifier OP-10 (OP-10), followed by the
chelation of iron ions, to develop a safe and effective method for
controlling Rhizoctonia solani in agriculture.
The encapsulated active component is a rosin-based triazole derivative
(RTD) previously synthesized by our research group (RTD@OP10-TA-Fe).
The encapsulation efficiency of the nanomicrocapsules is 82.39%, with
an effective compound loading capacity of 96.49%. Through the encapsulation
of the RTD via nanomicrocapsules, we improved its water solubility,
optimized its stability, and increased its adhesion to the leaf surface.
Under acidic conditions (pH = 5.0), the release rate of nanomicrocapsules
at 96 h is 96.31 ± 0.8%, which is 2.04 times higher than the
release rate under normal conditions (pH = 7.0). Additionally, the
results of in vitro and in vivo antifungal
assays indicate that compared with the original compound, the nanomicrocapsules
exhibit superior antifungal activity (EC50 values of RTD
and RTD@OP10-TA-Fe are 1.237 and 0.860 mg/L, respectively). The results
of field efficacy trials indicate that compared with RTD, RTD@OP10-TA-Fe
exhibits a more prolonged period of effectiveness. Even after 3 weeks,
the antifungal rate of RTD@OP10-TA-Fe remains at 40%, whereas RTD,
owing to degradation, shows an antifungal rate of 11.11% during the
same period. Furthermore, safety assessment results indicate that
compared with the control, RTD@OP10-TA-Fe has almost no impact on
the growth of rice seedlings and exhibits low toxicity to zebrafish.
This study provides valuable insights into controlling R. solani and enhancing the compound performance
Synthesis and Preliminary PET Imaging Studies of a FAAH Radiotracer ([<sup>11</sup>C]MPPO) Based on α‑Ketoheterocyclic Scaffold
Fatty
acid amide hydrolase (FAAH) is one of the principle enzymes
for metabolizing endogenous cannabinoid neurotransmitters such as
anandamide, and thus regulates endocannabinoid (eCB) signaling. Selective
pharmacological blockade of FAAH has emerged as a potential therapy
to discern the endogenous functions of anandamide-mediated eCB pathways
in anxiety, pain, and addiction. Quantification of FAAH in the living
brain by positron emission tomography (PET) would help our understanding
of the endocannabinoid system in these conditions. While most FAAH
radiotracers operate by an irreversible (“suicide”)
binding mechanism, a FAAH tracer with reversibility would facilitate
quantitative analysis. We have identified and radiolabeled a reversible
FAAH inhibitor, 7-(2-[<sup>11</sup>C]methoxyphenyl)-1-(5-(pyridin-2-yl)oxazol-2-yl)heptan-1-one
([<sup>11</sup>C]MPPO) in 13% radiochemical yield (nondecay corrected)
with >99% radiochemical purity and 2 Ci/μmol (74 GBq/μmol)
specific activity. The tracer showed moderate brain uptake (0.8 SUV)
with heterogeneous brain distribution. However, blocking studies with
a potent FAAH inhibitor URB597 demonstrated a low to modest specificity
to the target. Measurement of lipophilicity, metabolite, and efflux
pathway analysis were also performed to study the pharmacokinetic
profile of [<sup>11</sup>C]MPPO. In all, we reported an efficient
radiolabeling and preliminary evaluation of the first-in-class FAAH
inhibitor [<sup>11</sup>C]MPPO with α-ketoheterocyclic scaffold