Chemical composition and larvicidal activity of Zanthoxylum armatum against diamondback moth, Plutella xylostella

Behavioral, Electrophysiological, and Toxicological Responses of Plutella xylostella to Extracts from Angelica pubescens

Plutella xylostella L. is a destructive pest affecting cruciferous vegetables, causing massive economic losses worldwide. Plant-based insecticides are considered promising insect control agents. The Angelica pubescens extract inhibited female oviposition, with an oviposition deterrence index (ODI) of 61.65% at 12.5 mg/mL. We aimed to identify the bioactive compounds in A. pubescens extract. The compounds from A. pubescens extract were analyzed using LC-MS techniques. The toxicity and behavioral responses of larvae and adults of P. xylostella to ten compounds were investigated. We found that the caryophyllene oxide and 3,4-dimethoxycinnamic acid inhibited female oviposition; the ODIs were 98.31% and 97.59% at 1.25 mg/mL, respectively. The A. pubescens extract, caryophyllene oxide, and 3,4-dimethoxycinnamic acid caused larval mortality, with LC₅₀ values of 21.31, 4.56, and 5.52 mg/mL, respectively. The EAG response of females was higher than that of males under A. pubescens extract conditions, while the EAG response of males was higher than that of females in caryophyllene oxide and 3,4-dimethoxycinnamic acid conditions. The A. pubescens extract and caryophyllene oxide showed repellent activity against both female and male adults, while the 3,4-dimethoxycinnamic acid did not elicit any notable behavioral responses from P. xylostella adults. A. pubescens extract and caryophyllene oxide are potential insecticides, oviposition deterrents, and behavioral regulators against P. xylostella, and they could be potential candidates for the development of biological insecticides to control P. xylostella.

Identification of the Flavone-Inducible Counter-Defense Genes and Their cis-Elements in Helicoverpa armigera

Flavone is widely found in plants and plays an important role in plant defense against pests. Many pests, such as Helicoverpa armigera, use flavone as a cue to upregulate counter-defense genes for detoxification of flavone. Yet the spectrum of the flavone-inducible genes and their linked cis-regulatory elements remains unclear. In this study, 48 differentially expressed genes (DEGs) were found by RNA-seq. These DEGs were mainly concentrated in the retinol metabolism and drug metabolism-cytochrome P450 pathways. Further in silico analysis of the promoter regions of 24 upregulated genes predicted two motifs through MEME and five previously characterized cis-elements including CRE, TRE, EcRE, XRE-AhR and ARE. Functional analysis of the two predicted motifs and two different versions of ARE (named ARE1 and ARE2) in the promoter region of the flavone-inducible carboxylesterase gene CCE001j verified that the two motifs and ARE2 are not responsible for flavone induction of H. armigera counter-defense genes, whereas ARE1 is a new xenobiotic response element to flavone (XRE-Fla) and plays a decisive role in flavone induction of CCE001j. This study is of great significance for further understanding the antagonistic interaction between plants and herbivorous insects.

Overhauling the ecotoxicological impact of synthetic pesticides using plants' natural products: a focus on Zanthoxylum metabolites

The reduction in agricultural production due to the negative impact of insects and weeds, as well as the health and economic burden associated with vector-borne diseases, has promoted the wide use of chemicals that control these "enemies." However, the use of these synthetic chemicals has been recognized to elicit negative impacts on the environment as well as the health and wellbeing of man. In this study, we presented an overview of recent updates on the environmental and health impacts of synthetic pesticides against agro-pest and disease vectors while exhaustive reviewing the potentials of natural plant products from Zanthoxylum species (Rutaceae) as sustainable alternatives. This study is expected to spur further research on exploiting these plants and their chemicals as safe and effective pesticide entities to minimize the impact of their chemical and synthetic counterparts on health and the environment.

Alkylamides from Zanthoxylum armatum DC. and their neuroprotective activity

Zanthoxylum armatum DC. is an important medicinal plant, and its pericarps are commonly used as a natural spice in Asian countries. In this study, fifteen alkylamides were isolated and elucidated from the pericarps of Z. armatum, including five undescribed alkylamides (1-5) and ten known compounds (6-15). The molecular structures of all compounds were elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, among which the absolute configuration of compound 15 was determined by the Mo₂(OAc)₄-induced circular dichroism method. Moreover, all compounds were screened for their neuroprotective activity against H₂O₂-induced oxidative stress in human neuroblastoma SH-SY5Y cells for the evaluation of their neuroprotective activity. Especially, compounds 2-4 expressed potential neuroprotective activity, and further research showed that the cell viability was significantly enhanced in a concentration dependent manner when the cells were treated for 6 h. Moreover, compounds 2-4 could decrease reactive oxygen species accumulation. This paper enriched structure types of alkylamides in Zanthoxylum armatum.

Chemical composition, polyphenol contents and antioxidant activities of the 'Himalayan toothache relieving tree' (Zanthoxylum armatum DC.)

The present study carried out to investigate the bioactive chemical compounds, total polyphenol content and antioxidant potential of different extracts of the Zanthoxylum armatum leaves collected from the Nainital, Uttarakhand. The GC-MS analysis of Z. armtum leaves extract resulted in the isolation of sixty, twelve, twenty-three and nineteen phytochemical constituents in methanol, ethanol, chloroform and water extracts respectively. The leaves extracts were strongly characterised by Heneicosane, Tetratetracontane, Phytol, Fargesin, (+)- Seasmin and Paulowin. Methanol extract showed maximum DPPH (2,2-Di-phenyl-1-picryl-hydrazyl) Free radical scavenging activity (IC 50 15.63 ± 0.31), Ferric Reducing Antioxidant Activity (88.98 ± 3.34 AAE ± SD) and Metal Chelating Activity (IC 50 9.89 ± 0.83). The results showed that the methanolic extract exhibited the highest phenolic content for total phenol content (98.26 ± 0.8 mg of Gallic acid equivalent/g of dry weight), total flavonoid content (61.50 ± 1.62 mg of Quercetin equivalent/g of dry weight) and total tannin content (79.96 ± 0.81 mg of Tannic acid equivalent/g of dry weight).

Lethal and sublethal effects of essential oils fromPiper capitarianumYunck andPiper krukoffiiYunck onPlutella xylostellaL

Plutella xylostella (L.) is responsible for considerable vegetable crop losses in the metropolitan region of Manaus, Brazil. In recent decades, essential oils have been investigated as an alternative to synthetic insecticides. The genusPiperis widely distributed in Amazonia and essential oils from these plants have insecticidal properties. This study describes the chemical composition of the essential oils fromPiper capiterianumandPiper krukoffiias well as the lethal and sublethal effects onP. xylostella. The phytotoxicity of the oils on the host plant was also evaluated. Globulol was the major constituent of theP. krukoffiioil ando-cymene was the major constituent of theP. capitarianumoil. The oil fromP. capiterianumexhibited greater toxicity to larvae and eggs. This oil also presented greater repellant action, feeding deterrence and mild phytotoxicity to the host plant (Brassicae oleraceae). The findings suggest that this oil can be used in the preparation of a formulated insecticide for the management ofP. xylostellain different development phases. However, further studies are needed to evaluate the effect of this oil on crops under field conditions as well as non-target organisms and determine the cost-benefit ratio of a product formulated withP. capitarianumoil.

Controlling Enantioselectivity and Diastereoselectivity in Radical Cascade Cyclization for Construction of Bicyclic Structures

Radical cascade cyclization reactions are highly attractive synthetic tools for the construction of polycyclic molecules in organic synthesis. While it has been successfully implemented in diastereoselective synthesis of natural products and other complex compounds, radical cascade cyclization faces a major challenge of controlling enantioselectivity. As the first application of metalloradical catalysis (MRC) for controlling enantioselectivity as well as diastereoselectivity in radical cascade cyclization, we herein report the development of a Co(II)-based catalytic system for asymmetric radical bicyclization of 1,6-enynes with diazo compounds. Through the fine-tuning of D2-symmetric chiral amidoporphyrins as the supporting ligands, the Co(II)-catalyzed radical cascade process, which proceeds in a single operation under mild conditions, enables asymmetric construction of multisubstituted cyclopropane-fused tetrahydrofurans bearing three contiguous stereogenic centers, including two all-carbon quaternary centers, in high yields with excellent stereoselectivities. Combined computational and experimental studies have shed light on the underlying stepwise radical mechanism for this new Co(II)-based cascade bicyclization that involves the relay of several Co-supported C-centered radical intermediates, including α-, β-, γ-, and ε-metalloalkyl radicals. The resulting enantioenriched cyclopropane-fused tetrahydrofurans that contain a trisubstituted vinyl group at the bridgehead, as showcased in several stereospecific transformations, may serve as useful intermediates for stereoselective organic synthesis. The successful demonstration of this new asymmetric radical process via Co(II)-MRC points out a potentially general approach for controlling enantioselectivity as well as diastereoselectivity in synthetically attractive radical cascade reactions.

Copper Oxide Nanomaterials Derived from Zanthoxylum armatum DC. and Berberis lycium Royle Plant Species: Characterization, Assessment of Free Radical Scavenging and Antibacterial Activity

Copper oxide nanomaterials were synthesized by a facile sustainable biological method using two plant species (Zanthoxylum armatum DC. and Berberis lycium Royle). The formation of materials was confirmed by FT-IR, ATR, UV-visible, XRD, TEM, SEM, EDX, TGA and PL. The antibacterial activity was evaluated by agar well diffusion method to ascertain the efficacy of plant species extract and extract derived copper oxide nanomaterials against six Gram-positive bacteria namely Staphylococcus aureus, Streptococcus mutans, Streptococcus pyogenes, Corynebacterium diphtheriae, Corynebacterium xerosis, Bacillus cereus and four Gram-negative bacteria such as Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa and Proteus vulgaris against the standard drug, Ciprofloxacin for Gram-positive and Gentamicin for Gram-negative bacteria, respectively. In both cases, copper oxide nanomaterials were found to be sensitive in all the bacterial species. Sensitivity of copper oxide nanomaterials shows an be higher as compared to plant species extract against different bacteria. Scavenging activity of plant extracts along with nanomaterials have been accessed using previously reported protocols employing ascorbic acid as standard. Scavenging activity of copper oxide nanomaterials shows an increase with increase in concentration. The biological activity (bactericidal and scavenging efficiency) of plant derived copper oxide nanomaterials revealed that these materials can be used as potent antimicrobial agent and DPPH scavengers in industrial as well as pharmacological fields.

The complete chloroplast genome sequence of Zanthoxylum armatum

The first complete chloroplast genome sequences of Zanthoxylum armatum were reported in this study. The cpDNA of Z. armatum is 158,579 bp in length, contains a large single copy region (LSC) of 85,780 bp and a small single copy region (SSC) of 17,598 bp, which were separated by a pair of inverted repeat (IR) regions of 27,598 bp. The genome contains 133 genes, including 88 protein-coding genes, 8 ribosomal RNA genes, and 37 transfer RNA genes. The overall GC content of the whole genome is 38.5%. Phylogenetic analysis of 18 chloroplast genomes within the family Rutaceae suggests that Z. armatum is closely related to Zanthoxylum schinifolium.

Antifeedant Activities of Lignans from Stem Bark of Zanthoxylum armatum DC. against Tribolium castaneum

The speciation of a methanolic extract of Zanthoxylum armatum stem bark has enabled the isolation and characterization of 11 known lignans. Among them, five compounds (6, 8-11) are reported in this plant for the first time. All of the chemical structures were elucidated on the basis of NMR spectral analysis. Additionally, their antifeedant activities against Tribolium castaneum were evaluated scientifically. Among them, asarinin (1), with an EC50 of 25.64 ppm, exhibited a much stronger antifeedant activity than the positive control, toosendanin (EC50 = 71.69 ppm). Moreover, fargesin (2), horsfieldin (3), and magnolone (10), with EC50 values of 63.24, 68.39, and 78.37 ppm, showed almost the same antifeedant activity as the positive control. From the perspective of structure-effectiveness relationship, compounds with the chemical group of methylenedioxy exhibited higher antifeedant activities and have potential to be developed into novel antifeedants or potential lead compounds to protect food and crops in storage.

Bamboo-Leaf Prickly Ash extract: A potential bio-pesticide against oriental leaf worm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

Bamboo-Leaf Prickly Ash, Zanthoxylum armatum (Rutaceae) is a versatile and widely distributed plant species in nature. It is an edible plant species, commonly used in daily life for condiments and therapeutic remedies. Besides its bioactive and medicinal properties, different plant parts of the Z. armatum also have insecticidal potential. However, this potential has not been yet determined against many agricultural pests, including leaf worm, Spodoptera litura (Lepidoptera: Noctuidae). In this study, we demonstrated for the first time the contact and oral toxicity and sub-lethal effects (including antifeedent and ovicidal action) of various fractions of pericarp, leaf and seeds of Z. armatum against S. litura. Overall findings revealed that the n-hexane pericarp extract of Z. armatum has strong antifeedent, ovicidal and larvicidal properties against S. litura. Sub-lethal doses of pericarp extract can negatively alter the biology of S. litura. Since n-hexane extract of leaves also has better larvicidal properties, it could also be utilized for the S. litura management during period of unavailability of fruits (or pericarp). Accordingly, the Z. armatum pericarp and leaf extract has tremendous commercial utilization potential for the management of polyphagus pests like S. litura and other related species, which are quite difficult to manage even by chemical pesticides.

Two new phenolic glycosides from the stem of Zanthoxylum armatum DC

Two new phenolic glycoside, 2-methoxy-4-hydroxylphenyl-1-O-α-L-rhamnopyranosyl- (1″ → 6')-β-D-glucopyranoside. (1) and threo-3-methoxy-5-hydroxy-phenylpropanetriol-8-O-β-D-glucopyranoside (2), were isolated from the stems of Zanthoxylum armatum. The compounds 1 and 2 showed weak scavenging activity in DPPH free radical assay with IC₅₀ values of 323 and 114 mM, respectively.

Chemical Composition of Essential Oils from SixZanthoxylumSpecies and Their Repellent Activities against Two Stored-Product Insects

The objective of this study was to analyze six essential oils fromZanthoxylumgenus (family Rutaceae) in China and evaluate their repellent activities againstTribolium castaneumandLasioderma serricorneadults. Six essential oils fromZanthoxylumgenus, includingZ. armatum,Z. dimorphophyllum,Z. dimorphophyllumvar.spinifolium,Z. piasezkii,Z. stenophyllum,andZ. dissitum,were obtained by hydrodistillation and their yields were ranging from 0.02% to 0.53%. Totally, there were 39 chemical components revealed by GC-MS. Among them, some components with high relative content existed in more than threeZanthoxylumspecies. For instance, bothδ-cadinene (1.21%–17.15%) and spathulenol (0.36%–10.19%) appeared in essential oils ofZ. dimorphophyllum,Z. piasezkii,Z. stenophyllum,andZ. dissitumwhich were found to have higher content of sesquiterpenoids. The repellent activities of six essential oil samples againstT. castaneumandL. serricorneadults were investigated for the first time. Data demonstrated that sixZanthoxylumspecies had much stronger repellent activities againstT. castaneumthanL. serricorneadults, especially in 2 hours after exposure. The results indicate that these six essential oils fromZanthoxylumhave significant potential to be developed into natural repellents to control insects in grains, food, and traditional Chinese medicinal materials.