Identification and mechanism of insecticidal periplocosides from the root bark of Periploca sepium Bunge

Oviposition-deterrent activity of p-methyl benzaldehyde and 2-hydroxy-5-methoxybenzaldehyde from the extract of Periplocae cortex for the control of Spodoptera frugiperda

BACKGROUND

The invasion of Spodoptera frugiperda into China has caused serious losses to the food industry and has developed varying degrees of resistance to various chemical pesticides. Developing new plant-based pesticides is of great significance for the sustainable management of S. frugiperda.

RESULTS

p-Methyl benzaldehyde, 2-hydroxy-5-methoxybenzaldehyde and 2-hydroxy-4-methoxybenzaldehyde elicited strong electroantennogram (EAG) reactions from S. frugiperda adults. In particular, 14.4 mg/mL p-methyl benzaldehyde produced the strongest EAG reaction. At this concentration, olfactory selection results showed significant repellent activity against adults, while 0.09 mg/mL had significant attractant activity against males. 2-Hydroxy-5-methoxybenzaldehyde had significant attractive effects at 2.40, 7.20, 14.40 mg/mL. However, 0.80 and 14.4 mg/mL showed significant repellent effects on oviposition selection after treatment with p-methyl benzaldehyde, while 0.09 mg/mL showed significant attractant activity, with an oviposition index of 0.48 ± 0.12. Three treatments of 2-hydroxy-5-methoxybenzaldehyde showed significant repellent activity against the oviposition selection. In addition, exposure to these two substances could significantly inhibit the number of spermatophores and eggs laid by a single female.

CONCLUSION

p-Methyl benzaldehyde and 2-hydroxy-5-methoxybenzaldehyde in the secondary metabolites of the Chinese medicinal herb Periplocae cortex have obvious regulatory effects on the olfactory behavior and oviposition selection of Spodoptera frugiperda and significantly inhibit fertility. This result is helpful to understand the relationship between non-host plant secondary metabolites and insects, lay the foundation for new active substances as insect behavior regulators. © 2025 Society of Chemical Industry.

Periplosides Extract from Cortex periplocae Improve Collagen Antibody-Induced Arthritis by Regulating Macrophage Polarization

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized primarily by the synovial infiltration of inflammatory cells. Macrophage infiltration in the joint synovium is one of the early hallmarks of RA disease activity. Cortex periplocae, which has been widely employed in traditional Chinese medicine (TCM) to alleviate RA, harbors a bioactive compound known as Periploca sepium periplosides (PePs). In this study, collagen antibody-induced arthritis (CAIA) was established in mice through the administration of collagen antibodies and lipopolysaccharide (LPS), followed by treatment with PePs. The therapeutic effects of PePs were evaluated by measuring paw thickness, clinical arthritis scores, and histological changes in joint tissues. Flow cytometry and qRT-PCR were used to assess macrophage polarization in vivo and in vitro. The findings indicate that PePs effectively attenuated CAIA by suppressing the polarization of RAW264.7 cells towards the M1 phenotype while promoting their polarization towards the M2 phenotype. These results provide valuable insights into the scientific significance of PePs as a potential therapeutic agent for RA.

Discovery of the Chlorinated and Ammoniated Derivatives of Vanillin as Potential Insecticidal Candidates Targeting V-ATPase: Structure-Based Virtual Screening, Synthesis, and Bioassay

Vacuolar-type H+-ATPases (V-ATPases) play a crucial role in the life cycle of agricultural pests and represent a promising target for the development of novel insecticides. In this study, S18, a derivative of vanillin acquired from Specs database using a structure-based virtual screening methodology, was first identified as a V-ATPase inhibitor. It binds to subunit A of the enzyme with a Kd of 1 nM and exhibits insecticidal activity against M. separata. Subsequently, using S18 as the lead compound, a new series of vanillin derivatives were rationally designed and efficiently synthesized. and their biological activities were assessed. Among them, compound 3b-03 showed the strongest insecticidal activity against M. separata by effectively targeting the V-ATPase subunit A with Kd of 0.803 μM. Isothermal titration calorimetric measurements and docking results provided insights into its interaction with subunit A of V-ATPase, which could facilitate future research aimed at the development of novel chemical insecticides.

Exploring the Potential of Myrcia Genus Essential Oils: A Review of Biological Activities and Recent Advances

The present study provides a comprehensive analysis of the chemical composition of essential oils from species of the Myrcia genus and their applications. The compiled results highlight the chemical diversity and biological activities of these oils, emphasizing their potential importance for various therapeutic and industrial applications. The findings reveal that Myrcia essential oils present a variety of bioactive compounds, such as monoterpenes and sesquiterpenes, which demonstrate antimicrobial activities against a range of microorganisms, including Gram-positive and Gram-negative bacteria, as well as yeasts. Furthermore, this study highlights the phytotoxic activity of these oils, indicating their potential for weed control. The results also point to the insecticidal potential of Myrcia essential oils against a range of pests, showing their viability as an alternative to synthetic pesticides. Additionally, species of the genus Myrcia have demonstrated promising hypoglycemic effects, suggesting their potential in diabetes treatment. This comprehensive synthesis represents a significant advancement in understanding Myrcia essential oils, highlighting their chemical diversity and wide range of biological activities. However, the need for further research is emphasized to fully explore the therapeutic and industrial potential of these oils, including the identification of new compounds, understanding of their mechanisms of action, and evaluation of safety and efficacy in different contexts.

Effects of periplocoside T isolated from Periploca sepium on behavior and sensory-CNS-motor circuits in Drosophila melanogaster larvae

Periplocoside T (PST) from Periploca sepium has insecticidal activity against some lepidopterans, which can significantly inhibit the activity of vacuolar-type H⁺-ATPases (V-ATPase). V-ATPase is involved in the release of neurotransmitters in vesicles during nerve signal transduction. However, there are actions of PST on behavior and sensory-central nervous system (CNS)-motor neural circuit which are commonly overlooked. After exposure to 500 mg/L PST for 48 h, the difference of the proportion of larvae responding to stimuli in the four Drosophila strains was not significant as compared to controls, but larval mouth hook movement and body wall motion were significantly decreased as compared to controls, and the decrease was more obvious in para^ts1; DSC1^-/- and DSC1^-/- strains, especially in para^ts1; DSC1^-/- strain. Compared with control (DMSO), the excitatory junction potential (EJP) frequencies of sensory-CNS-motor circuits in the four Drosophila strains after PST or bafiloymcin A1 (BA1, a V-ATPase specific inhibitor) treatment gradually decreased with time, and the decreasing amplitude of BA1 treatment was greater than that of PST treatment, but both were higher than that of the control. The decay amplitude of EJP frequency in two strains with DSC1 channel knockout was lower than that of w¹¹¹⁸ and para^ts1 strains without DSC1 channel knockout. Thus, the results indicated that PST, similar to BA1, could inhibit the transmission of sensory-CNS-motor circuit excitability of Drosophila larvae by inhibiting the activity of V-ATPase, and DSC1 channel play a role of in regulating the stability of nervous system.

Synthesis, Crystal Structure, and Insecticidal Activity of Steroidal N-Piperidone

A series of steroidal piperidone derivatives were synthesized, and their agricultural activities were evaluated against Myzus persicae, Aphis citricola, Brevicoryne brassicae Linn., and Bemisia tabaci (Gennadius). Most of the tested compounds exhibited potent insecticidal activity against these four pests. Compound I-9 displayed the highest activity against M. persicae, A. citricola, and Brevicoryne brassicae, with LC₅₀ values of 11.3, 10.4, and 8.68 μg/mL, respectively. The mode of action test indicated that these derivatives had superior contact and systemic insecticidal activity against M. persicae. In addition, we initially explored whether the foregut and midgut might be the action sites of the target derivatives against M. persicae. Furthermore, a field trial showed that the control of compound I-9 was similar to that of acetamiprid against M. persicae, at a dose of 50 μg/mL; the control rates were 97.8 and 99.2% after 14 and 21 days, respectively. The structure-activity relationship of these analogues provided some important insights for the discovery and development of new insecticides to solve the current pesticide resistance crisis.

Genus Sophora: a comprehensive review on secondary chemical metabolites and their biological aspects from past achievements to future perspectives

Sophora is deemed as one of the most remarkable genera of Fabaceae, and the third largest family of flowering plants. The genus Sophora comprises approximately 52 species, 19 varieties, and 7 forms that are widely distributed in Asia and mildly in Africa. Sophora species are recognized to be substantial sources of broad spectrum biopertinent secondary metabolites namely flavonoids, isoflavonoids, chalcones, chromones, pterocarpans, coumarins, benzofuran derivatives, sterols, saponins (mainly triterpene glycosides), oligostilbenes, and mainly alkaloids. Meanwhile, extracts and isolated compounds from Sophora have been identified to possess several health-promising effects including anti-inflammatory, anti-arthritic, antiplatelets, antipyretic, anticancer, antiviral, antimicrobial, antioxidant, anti-osteoporosis, anti-ulcerative colitis, antidiabetic, anti-obesity, antidiarrheal, and insecticidal activities. Herein, the present review aims to provide comprehensive details about the phytochemicals and biological effects of Sophora species. The review spotlighted on the promising phytonutrients extracted from Sophora and their plethora of bioactivities. The review also clarifies the remaining gaps and thus qualifies and supplies a platform for further investigations of these compounds.