Botanical herbicide has been a hot topic in the research and development of novel pesticides. The herbicidal activity and biochemical characteristics of the botanical compound drupacine were studied by evaluating its ...Botanical herbicide has been a hot topic in the research and development of novel pesticides. The herbicidal activity and biochemical characteristics of the botanical compound drupacine were studied by evaluating its effects on seed germination, seedling growth, morphological and physiological characteristics of Amaranthus retroflexus. Drupacine inhibited seed germination and seedling growth, and had a median inhibition concentration(IC50) value of 38.99 mg L-1against A. retroflexus root. The α-amylase activity and soluble sugar content in treated plants were significantly lower than that of the control. The expression of α-amylase gene was dosage-dependently inhibited compared to the untreated control. This suggested that inhibition of α-amylase activity was a mode of action on seed germination. The root hairs were significantly decreased and part of the root cap fell off after treatment with drupacine. The ultrastructure observation showed that cell damage of root tips increased with the treatment time. Drupacine also increased the relative conductivity and malondialdehyde(MDA) content. Peroxidase(POD), catalase(CAT), and superoxide dismutase(SOD) activities were significantly enhanced in the treatment compared to the control. These findings indicated that the physiological and biochemical reaction changes leading to morphological and membrane injuries were the main effects of drupacine on the inhibition of seedling growth. Drupacine can be developed as a botanical herbicide.展开更多
Despite the availability of vaccines and antiviral treatments,the continued emergence of severe acute respira-tory syndrome coronavirus 2(SARS-CoV-2)variants and breakthrough infections underscores the need for new,po...Despite the availability of vaccines and antiviral treatments,the continued emergence of severe acute respira-tory syndrome coronavirus 2(SARS-CoV-2)variants and breakthrough infections underscores the need for new,potent antiviral therapies.In a previous study,we established a transcription and replication-competent SARS-CoV-2 virus-like particle(trVLP)system that recapitulates the complete viral life cycle.In this study,we combined high-content screening(HCS)with the SARS-CoV-2 trVLP cell culture system,providing a powerful phenotype-oriented approach to assess the antiviral potential of compounds on a large scale.We screened a library of 3,200 natural compounds and identified drupacine as a potential candidate against SARS-CoV-2 infection.Furthermore,we utilized a SARS-CoV-2 replicon system to demonstrate that drupacine could inhibit viral genome transcription and replication.However,in vitro,enzymatic assays revealed that the inhibition could not be attributed to conventional antiviral targets,such as the viral non-structural proteins nsp5(MPro)or nsp12(RdRp).In conclusion,our findings position drupacine as a promising antiviral candidate against SARS-CoV-2,providing a novel scaffold for developing anti-coronavirus disease 2019 therapeutics.Further investigation is required to pinpoint its precise target and mechanism of action.展开更多
基金funded by the Provincial Natural Science Foundation of Hebei for Excellent Young Scholar, China (C2021204071)the Science and Technology Project of Hebei Education Department (QN2021079)+1 种基金the Key Research and Development Project of Hebei Province (21326511D and 19226504D)the China Agriculture Research System of MOF and MARA (CARS-02)。
文摘Botanical herbicide has been a hot topic in the research and development of novel pesticides. The herbicidal activity and biochemical characteristics of the botanical compound drupacine were studied by evaluating its effects on seed germination, seedling growth, morphological and physiological characteristics of Amaranthus retroflexus. Drupacine inhibited seed germination and seedling growth, and had a median inhibition concentration(IC50) value of 38.99 mg L-1against A. retroflexus root. The α-amylase activity and soluble sugar content in treated plants were significantly lower than that of the control. The expression of α-amylase gene was dosage-dependently inhibited compared to the untreated control. This suggested that inhibition of α-amylase activity was a mode of action on seed germination. The root hairs were significantly decreased and part of the root cap fell off after treatment with drupacine. The ultrastructure observation showed that cell damage of root tips increased with the treatment time. Drupacine also increased the relative conductivity and malondialdehyde(MDA) content. Peroxidase(POD), catalase(CAT), and superoxide dismutase(SOD) activities were significantly enhanced in the treatment compared to the control. These findings indicated that the physiological and biochemical reaction changes leading to morphological and membrane injuries were the main effects of drupacine on the inhibition of seedling growth. Drupacine can be developed as a botanical herbicide.
基金supported by the National Natural Science Foundation of China(82341084,82241077,82272302,and 32070153)National Key Research and Development Plan of China(2023YFC2305900 and 2021YFC2300200-04)Tsinghua University Dushi Program(20231080039)。
文摘Despite the availability of vaccines and antiviral treatments,the continued emergence of severe acute respira-tory syndrome coronavirus 2(SARS-CoV-2)variants and breakthrough infections underscores the need for new,potent antiviral therapies.In a previous study,we established a transcription and replication-competent SARS-CoV-2 virus-like particle(trVLP)system that recapitulates the complete viral life cycle.In this study,we combined high-content screening(HCS)with the SARS-CoV-2 trVLP cell culture system,providing a powerful phenotype-oriented approach to assess the antiviral potential of compounds on a large scale.We screened a library of 3,200 natural compounds and identified drupacine as a potential candidate against SARS-CoV-2 infection.Furthermore,we utilized a SARS-CoV-2 replicon system to demonstrate that drupacine could inhibit viral genome transcription and replication.However,in vitro,enzymatic assays revealed that the inhibition could not be attributed to conventional antiviral targets,such as the viral non-structural proteins nsp5(MPro)or nsp12(RdRp).In conclusion,our findings position drupacine as a promising antiviral candidate against SARS-CoV-2,providing a novel scaffold for developing anti-coronavirus disease 2019 therapeutics.Further investigation is required to pinpoint its precise target and mechanism of action.
