A Hidden Cause of Hypertransaminasemia: Liver Toxicity Caused by Chelidonium Majus L. : Report of Two Cases of Herb-Induced Liver Injury and Literature Review.

BACKGROUND: In instances where individuals manifest elevated transaminase levels without a clearly discernible cause, a comprehensive patient history proves invaluable in unveiling latent triggers. In this report, we present 2 cases of herb-induced liver injury (HILI) characterized by severe hypertransaminasemia attributed to the consumption of Chelidonium majus L . (also known as greater celandine [GC]), an agent considered an alternative therapeutic remedy. AREAS OF UNCERTAINTY: Exploring the occurrence and range of clinical manifestations in HILI linked to Chelidonium majus L ., while also investigating the potential triggers and predisposing factors for hepatotoxic reactions post Chelidonium majus L. usage, remains challenging due to the absence of definitive laboratory tests to identify the causative agent. DATA SOURCES: Two case reports were detailed, and a systematic literature review using PubMed was conducted including published literature till March 2023. Moreover, a manual search of reference lists of pertinent articles was performed to identify any additional relevant missed publications. RESULTS: In the first case, a 64-year-old woman presented with jaundice, revealing a 1-month history of using GC capsules to manage gallstones. Diagnostic assessment identified HILI, gallstones, and choledocolithiasis, with transaminase levels exceeding 1000 IU/L. After discontinuing GC and receiving intravenous therapy with amino acids and phospholipids, the patient's condition significantly improved. Subsequently, she underwent endoscopic common bile duct stone removal and cholecystectomy. In the second case, a 66-year-old woman presented with elevated liver function test results discovered incidentally during musculoskeletal pain evaluation. Upon further questioning, the patient disclosed regular consumption of GC tea for "health promotion." Following intravenous therapy using amino acids and phospholipids, her transaminase levels returned to normal. The literature review identified 38 cases of HILI associated with GC preparations, primarily in adult women aged 27-77 years, with a predominant reporting location in Germany. Various forms of GC were used, with treatment durations ranging from 1 week to a year. Discontinuation of GC generally led to recovery in these cases. CONCLUSION: Chelidonium majus L ., a potent herb often used in alternative medicine, has significant hepatotoxic potential, requiring physicians to be vigilant in cases of unexplained liver injury.

The Greater Celandine: Identification and Characterization of an Antimicrobial Peptide from Chelidonium majus.

Chelidonium majus, known as Greater Celandine, is a latex-bearing plant that has been leveraged for its anticancer and antimicrobial properties. Herein, C. majus aerial tissue is mined for the presence of antimicrobial peptides. A highly abundant cysteine-rich peptide with a length of 25 amino acids, deemed CM-AMP1, is characterized through multiple mass spectrometric approaches. Electron-activated dissociation is leveraged to differentiate between isoleucine and leucine residues and complement conventional collision-induced dissociation to gain full sequence coverage of the full-length peptide. CM-AMP1 shares little sequence similarity with any proteins in publicly available databases, highlighting the novelty of its cysteine landscape and core motif. The presence of three disulfide bonds in the native peptide confers proteolytic stability, and antimicrobial activity is greatly decreased upon the alkylation of the cysteine residues. Synthetic variants of CM-AMP1 are used to confirm the activity of the full-length sequence and the core motif. To assess the biological impact, E. coli was grown in a sublethal concentration of CM-AMP1 and quantitative proteomics was used to identify proteins produced by the bacteria under stress, ultimately suggesting a membrane lytic antimicrobial mechanism of action. This study integrates multiple analytical methods for molecular and biological characterization of a unique antimicrobial peptide identified from C. majus.

Novel Approaches for the Analysis and Isolation of Benzylisoquinoline Alkaloids in Chelidonium majus.

Benzylisoquinoline alkaloids are the major bioactive components in Chelidonium majus, a plant that has a long usage history for the treatment of gastrointestinal ailments in European and Asian phytomedicine. This study reports on the development and application of a supercritical fluid chromatography technique for the simultaneous qualitative and quantitative determination of seven benzylisoquinoline alkaloids in under six minutes using a Viridis BEH 2-EP column and a modifier comprising methanol with 30% acetonitrile and 20 mM ammonium formate. The method was fully validated according to ICH guidelines showing, e.g., excellent linearity (≥ 0.9997) and maximum deviations for intraday and inter-day precision of 2.99 and 2.76%, respectively. The new supercritical fluid chromatography assay was not only employed for the analysis of several C. majus samples but was also used for the subsequent development of a fast centrifugal partition chromatography technique, whereby five benzylisoquinoline alkaloids could be isolated within approximately 2.5 h, with only two of them, protopine and chelidonine, requiring an additional purification step. To achieve this, a solvent system composed of chloroform/methanol/0.3 M hydrochloric acid was used in descending mode. By injecting 500 mg of crude extract, stylopine (1.93 mg), sanguinarine (0.57 mg), chelidonine (1.29 mg), protopine (1.95 mg), and coptisine (7.13 mg) could be obtained. The purity of compounds was confirmed by supercritical fluid chromatography and MS.

Screening of Chelidonium majus isoquinoline alkaloids reveals berberine and chelidonine as selective ligands for the nuclear receptors RORß and HNF4α, respectively.

The nuclear receptors hepatocyte nuclear factor 4α (HNF4α) and retinoic acid receptor-related orphan receptor-ß (RORß) are ligand-regulated transcription factors and potential drug targets for metabolic disorders. However, there is a lack of small molecular, selective ligands to explore the therapeutic potential in further detail. Here, we report the discovery of greater celandine (Chelidonium majus) isoquinoline alkaloids as nuclear receptor modulators: Berberine is a selective RORß inverse agonist and modulated target genes involved in the circadian clock, photoreceptor cell development, and neuronal function. The structurally related chelidonine was identified as a ligand for the constitutively active HNF4α receptor, with nanomolar potency in a cellular reporter gene assay. In human liver cancer cells naturally expressing high levels of HNF4α, chelidonine acted as an inverse agonist and downregulated genes associated with gluconeogenesis and drug metabolism. Both berberine and chelidonine are promising tool compounds to further investigate their target nuclear receptors and for drug discovery.

Determination of Selected Isoquinoline Alkaloids from Chelidonium majus, Mahonia aquifolium and Sanguinaria canadensis Extracts by Liquid Chromatography and Their In Vitro and In Vivo Cytotoxic Activity against Human Cancer Cells.

The search for new substances with cytotoxic activity against various cancer cells, especially cells that are very resistant to currently used chemotherapeutic agents, such as melanoma cells, is a very important scientific aspect. We investigated the cytotoxic effect of Chelidonium majus, Mahonia aquifolium and Sanguinaria canadensis extracts obtained from different parts of these plants collected at various vegetation stages on FaDu, SCC-25, MCF-7, and MDA-MB-231 cancer cells. Almost all the tested extracts showed higher cytotoxicity against these cancer cells than the anticancer drug etoposide. The highest cytotoxicity against the FaDu, SCC-25, MCF-7 and MDA-MB-231 cancer cell lines was obtained for the Sanguinaria candensis extract collected before flowering. The cytotoxicity of extracts obtained from different parts of Chelidonium majus collected at various vegetation stages was also evaluated on melanoma cells (A375, G361 and SK-MEL-3). The highest cytotoxic activity against melanoma A375 cells was observed for the Chelidonium majus root extract, with an IC50 of 12.65 µg/mL. The same extract was the most cytotoxic against SK-MEL-3 cells (IC50 = 1.93 µg/mL), while the highest cytotoxic activity against G361 cells was observed after exposure to the extract obtained from the herb of the plant. The cytotoxic activity of Chelidonium majus extracts against melanoma cells was compared with the cytotoxicity of the following anticancer drugs: etoposide, cisplatin and hydroxyurea. In most cases, the IC50 values obtained for the anticancer drugs were higher than those obtained for the Chelidonium majus extracts. The most cytotoxic extract obtained from the root of Chelidonium majus was selected for in vivo cytotoxic activity investigations using a Danio rerio larvae xenograft model. The model was applied for the first time in the in vivo investigations of the extract's anticancer potential. The application of Danio rerio larvae xenografts in cancer research is advantageous because of the transparency and ease of compound administration, the small size and the short duration and low cost of the experiments. The results obtained in the xenograft model confirmed the great effect of the investigated extract on the number of cancer cells in a living organism. Our investigations show that the investigated plant extracts exhibit very high cytotoxic activity and can be recommended for further experiments in order to additionally confirm their potential use in the treatment of various human cancers.

The Activity of Chelidonium majus L. Latex and Its Components on HPV Reveal Insights into the Antiviral Molecular Mechanism.

Yellow-orange latex of Chelidonium majus L. has been used in folk medicine as a therapeutic agent against warts and other visible symptoms of human papillomavirus (HPV) infections for centuries. The observed antiviral and antitumor properties of C. majus latex are often attributed to alkaloids contained therein, but recent studies indicate that latex proteins may also play an important role in its pharmacological activities. Therefore, the aim of the study was to investigate the effect of the crude C. majus latex and its protein and alkaloid-rich fractions on different stages of the HPV replication cycle. The results showed that the latex components, such as alkaloids and proteins, decrease HPV infectivity and inhibit the expression of viral oncogenes (E6, E7) on mRNA and protein levels. However, the crude latex and its fractions do not affect the stability of structural proteins in HPV pseudovirions and they do not inhibit the virus from attaching to the cell surface. In addition, the protein fraction causes increased TNFα secretion, which may indicate the induction of an inflammatory response. These findings indicate that the antiviral properties of C. majus latex arise both from alkaloids and proteins contained therein, acting on different stages of the viral replication cycle.

Effectiveness of Volatile Natural Deep Eutectic Solvents (VNADESs) for the Green Extraction of Chelidonium majus Isoquinoline Alkaloids.

The Chelidonium majus plant is rich in biologically active isoquinoline alkaloids. These alkaline polar compounds are isolated from raw materials with the use of acidified water or methanol; next, after alkalisation of the extract, they are extracted using chloroform or dichloromethane. This procedure requires the use of toxic solvents. The present study assessed the possibility of using volatile natural deep eutectic solvents (VNADESs) for the efficient and environmentally friendly extraction of Chelidonium alkaloids. The roots and herb of the plant were subjected three times to extraction with various menthol, thymol, and camphor mixtures and with water and methanol (acidified and nonacidified). It has been shown that alkaloids can be efficiently isolated using menthol-camphor and menthol-thymol mixtures. In comparison with the extraction with acidified methanol, the use of appropriate VNADESs formulations yielded higher amounts of protopine (by 16%), chelidonine (35%), berberine (76%), chelerythrine (12%), and coptisine (180%). Sanguinarine extraction efficiency was at the same level. Additionally, the values of the contact angles of the raw materials treated with the tested solvents were assessed, and higher wetting dynamics were observed in the case of VNADESs when compared with water. These results suggest that VNADESs can be used for the efficient and environmentally friendly extraction of Chelidonium alkaloids.

Eutectic Thin-Layer Chromatography as a New Possibility for Quantification of Plant Extracts-A Case Study.

Deep eutectic solvents (DES), compared to classic ones, have interesting properties, such as the ability to solubilize compounds differing in polarity or increased dissolution of selected chemical compounds. They also offer specific interactions between the mobile and stationary phases. Those features make them promising solvents in chromatographic techniques, including the use in the separation of complicated samples. The first quantitative analysis with eutectic thin-layer chromatography (TLC) is presented in the paper. As a case study, five alkaloids from Chelidonium maius were selected as target compounds. A wide range of terpene-based DESs was investigated to develop the chromatographic system, both pure and after dilution. Moreover, a novel approach was employed to adjust polarity, involving mixing DESs differing in chromatographic properties. This procedure has proved to be effective. The best results were obtained with a 2:1 (wt/wt) mixture of DESs: camphor + phenol and menthol + limonene, with a 20% addition of methanol. The chromatographic system was validated and checked on the real sample, which made it the first applicable and operational quantitative eutectic TLC system.

Chelidonium majus crude extract induces activation of peripheral blood mononuclear cells and enhances their cytotoxic effect toward HeLa cells.

The aim of the study was to examine the immunomodulatory effect of crude Chelidonium majus L ethanolic extract on ex vivo harvested peripheral blood mononuclear cells (PBMNCs). PBMNCs were isolated by density gradient centrifugation. The PBMNC cytotoxicity assay was performed with HeLa tumor cells as target cells. MTT assay was used to estimate the proliferation effect of extract and cytotoxic efficiency of treated PBMNCs. Flow cytometric analysis was used for immunophenotyping. Treatment induced moderate proliferative response, perturbation in PBMNC ratios, and the emergence of some unconventional subpopulations. The percentage ratio of double positive CD4+ and CD8+ T lymphocytes and monocytes, ratio of T and B lymphocytes expressing CD14, and percentage of NK cells expressing CD57 increased after treatment, indicating activation of PBMNC subpopulations. Cytotoxic activity against HeLa cells was enhanced. Activation of PBMNCs and enhancement of their cytotoxic effect toward HeLa cells indicate the immunostimulatory effect of Ch. majus ethanolic extract.

Greater celandine (Chelidonium majus L.) for COVID-19: A twenty-case series.

In December 2019, an outbreak of coronavirus disease 2019 (COVID-19) occurred in Wuhan, China, with a rapid increase in cases worldwide. Until now, among several drugs tested, none demonstrated sufficient efficacy for its etiological treatment. Greater celandine (Chelidonium majus L.) is a well-known medicinal plant, traditionally indicated for digestive disorders and topically to remove warts. This study, performed at private offices in São Paulo and Aracaju (Brazil), describes 20 consecutive COVID-19 outpatients treated with greater celandine and their clinical evolution. The patients, aged 14-71 years (median of 41 years), were treated with Chelidonium majus 10% mother tincture, 20-30 drops three times a day for 3-12 days (median of 5 days). Clinical features were assessed during the treatment and at least until 1 week after its end. These cases were considered mild, as most COVID-19 cases. The symptoms were mainly fever, fatigue, cough, sore throat, coryza, anosmia, ageusia, and headache. Ten patients had comorbidities, such as hypertension, diabetes, and overweight. Complete or almost complete clinical improvement occurred within 1-9 days of treatment (median of 3 days). There were no adverse events. This casuistry, although small, may inspire other researchers to continue investigating Chelidonium majus as a healing treatment for COVID-19.

Functional Studies of Plant Latex as a Rich Source of Bioactive Compounds: Focus on Proteins and Alkaloids.

Latex, a sticky emulsion produced by specialized cells called laticifers, is a crucial part of a plant's defense system against herbivory and pathogens. It consists of a broad spectrum of active compounds, which are beneficial not only for plants, but for human health as well, enough to mention the use of morphine or codeine from poppy latex. Here, we reviewed latex's general role in plant physiology and the significance of particular compounds (alkaloids and proteins) to its defense system with the example of Chelidonium majus L. from the poppy family. We further attempt to present latex chemicals used so far in medicine and then focus on functional studies of proteins and other compounds with potential pharmacological activities using modern techniques such as CRISPR/Cas9 gene editing. Despite the centuries-old tradition of using latex-bearing plants in therapies, there are still a lot of promising molecules waiting to be explored.

Combined Protein and Alkaloid Research of Chelidonium majus Latex Reveals CmMLP1 Accompanied by Alkaloids with Cytotoxic Potential to Human Cervical Carcinoma Cells.

Chelidonium majus L. is a latex-bearing plant used in traditional folk medicine to treat human papillomavirus (HPV)-caused warts, papillae, and condylomas. Its latex and extracts are rich in many low-molecular compounds and proteins, but there is little or no information on their potential interaction. We describe the isolation and identification of a novel major latex protein (CmMLP1) composed of 147 amino acids and present a model of its structure containing a conserved hydrophobic cavity with high affinity to berberine, 8-hydroxycheleritrine, and dihydroberberine. CmMLP1 and the accompanying three alkaloids were present in the eluted chromatographic fractions of latex. They decreased in vitro viability of human cervical cancer cells (HPV-negative and HPV-positive). We combined, for the first time, research on macromolecular and low-molecular-weight compounds of latex-bearing plants in contrast to other studies that investigated proteins and alkaloids separately. The observed interaction between latex protein and alkaloids may influence our knowledge on plant defense. The proposed toolbox may help in further understanding of plant disease resistance and in pharmacological research.

Effects of Abiotic Elicitors on Expression and Accumulation of Three Candidate Benzophenanthridine Alkaloids in Cultured Greater Celandine Cells.

Efforts to develop the necessary biotechnologies in Greater Celandine (Chelidonium majus L.), a leading plant resource for the development of plant-derived medicines, have been hampered by the lack of knowledge about transcriptome and metabolome regulations of its medicinal components. Therefore, this study aimed to examine the effect of abiotic elicitors, methyl jasmonate (MJ) and salicylic acid (SA), at different time courses (12, 24, 48, and 72 h), on expression and metabolome of key benzophenanthridine alkaloids (BPAs) in an optimized in vitro culture. Gene expression analysis indicated the upregulation of CFS (cheilanthifoline synthase) to 2.62, 4.85, and 7.28 times higher than the control at 12, 24, and 48 h respectively, under MJ elicitation. Besides, MJ upregulated the expression of TNMT (tetrahydroprotoberberine N-methyltransferase) to 2.79, 4.75, and 7.21 times at 12, 24, and 48 h respectively, compared to the control. Investigation of BPAs revealed a significant enhancement in the chelidonine content (9.86 µg/mg) after 72 h of MJ elicitation. Additionally, sanguinarine content increased to its highest level (3.42 µg/mg) after 24 h of MJ elicitation; however, no significant enhancement was detected in its content in shorter elicitation time courses. Generally, higher gene expression and BPAs' level was observed through longer elicitation courses (48 and 72 h). Our findings take part in improving the understanding of transcription and metabolic regulation of BPAs in cultured Greater Celandine cells.

In vitro antifungal activity and possible mechanisms of action of chelerythrine.

Chelerythrine (CHE) possesses broad pharmacological activities. In this study, the extract of Chelidonium majus L. were characterized by high performance liquid chromatography (HPLC), infrared radiation (IR) spectroscopy and nuclear magnetic resonance (NMR). It was proved that the extract was CHE. The antifungal activity of CHE against five fungal pathogens of rice was researched in vitro, revealing that CHE inhibited Ustilaginoidea virens (U. virens) and Cochliobolus miyabeanus (C. miyabeanus) with 50% effective concentrations (EC50) of 6.53 × 10-3 mg/mL and 5.62 × 10-3 mg/mL, respectively. When the concentration of CHE was 7.5 × 10-3 mg/mL, the inhibition rate of U. virens reached 56.1%. Moreover, CHE (4 × 10-3 mg/mL) exhibited the greatest efficacy in inhibiting spore of U. virens growth with an inhibition rate as high as 86.7%. CHE displayed the best inhibitory activity against U. virens at the concentration of 7.5 × 10-3 mg/mL, compared with the other two isoquinoline alkaloids and commercial fungicide validamycin. After treating U. virens mycelia with CHE, twisted and atrophied mycelia were observed by optical microscopy. SEM results demonstrated narrow and locally fractured mycelium. TEM observations showed that the cell wall had become thin and broken, and most organelles were difficult to recognize. Furthermore, membrane of mycelia was destroyed and reactive oxygen species (ROS) of spores was accumulated, which induced apoptosis of pathogenic fungi. From these results, our understanding of the mechanisms of antifungal activity of CHE against U. virens was enriched and this research is relevant for developing novel pesticides.

Green Synthesis of Ag-MnO2 Nanoparticles using Chelidonium majus and Vinca minor Extracts and Their In Vitro Cytotoxicity.

Medicinal plants are often used as reducing agents to prepare metal nanoparticles through green-synthesis due to natural compounds and their potential as chemotherapeutic drugs. Thus, three types of eco-friendly Ag-MnO2 nanoparticles (Ag-MnO2NPs) were synthesized using C. majus (CmNPs), V. minor (VmNPs), and a 1:1 mixture of the two extracts (MNPs). These NPs were characterized using S/TEM, EDX, XRD, and FTIR methods, and their biological activity was assessed in vitro on normal keratinocytes (HaCaT) and skin melanoma cells (A375). All synthesized NPs had manganese oxide in the middle, and silver oxide and plant extract on the exterior. The NPs had different forms (polygonal, oval, and spherical), uniformly distributed, with crystalline structures and different sizes (9.3 nm for MNPs; 10 nm for VmNPs, and 32.4 nm for CmNPs). The best results were obtained with VmNPs, which reduced the viability of A375 cells up 38.8% and had a moderate cytotoxic effect on HaCaT (46.4%) at concentrations above 500 µg/mL. At the same concentrations, CmNPs had a rather proliferative effect, whereas MNPs negatively affected both cell lines. For the first time, this paper proved the synergistic action of the combined C. majus and V. minor extracts to form small and uniformly distributed Ag-MnO2NPs with high potential for selective treatments.

Modulatory Effect of Chelidonium majus Extract and Its Alkaloids on LPS-Stimulated Cytokine Secretion in Human Neutrophils.

Due to certain differences in terms of molecular structure, isoquinoline alkaloids from Chelidonium majus engage in various biological activities. Apart from their well-documented antimicrobial potential, some phenanthridine and protoberberine derivatives as well as C. majus extract present with anti-inflammatory and cytotoxic effects. In this study, the LC-MS/MS method was used to determine alkaloids, phenolic acids, carboxylic acids, and hydroxybenzoic acids. We investigated five individually tested alkaloids (coptisine, berberine, chelidonine, chelerythrine, and sanguinarine) as well as C. majus root extract for their effect on the secretion of IL-1ß, IL-8, and TNF-α in human polymorphonuclear leukocytes (neutrophils). Berberine, chelidonine, and chelerythrine significantly decreased the secretion of TNF-α in a concentration-dependent manner. Sanguinarine was found to be the most potent inhibitor of IL-1ß secretion. However, the overproduction of IL-8 and TNF-α and a high cytotoxicity for these compounds were observed. Coptisine was highly cytotoxic and slightly decreased the secretion of the studied cytokines. The extract (1.25-12.5 µg/mL) increased cytokine secretion in a concentration-dependent manner, but an increase in cytotoxicity was also noted. The alkaloids were active at very low concentrations (0.625-2.5 µM), but their potential cytotoxic effects, except for chelidonine and chelerythrine, should not be ignored.

Enantioselective Syntheses of Strychnos and Chelidonium Alkaloids through Regio- and Stereocontrolled Cooperative Catalysis.

We describe enantioselective syntheses of strychnos and chelidonium alkaloids. In the first case, indole acetic acid esters were established as excellent partner nucleophiles for enantioselective cooperative isothiourea/Pd catalyzed α-alkylation. This provides products containing indole-bearing stereocenters in high yield and with excellent levels of enantioinduction in a manner that is notably independent of the N-substituent. This led to concise syntheses of (-)-akuammicine and (-)-strychnine. In the second case, the poor performance of ortho-substituted cinnamyl electrophiles in the enantioselective cooperative isothiourea/Ir catalyzed α-alkylation was overcome by appropriate substituent choice, leading to enantioselective syntheses of (+)-chelidonine, (+)-norchelidonine, and (+)-chelamine.

Development of a Selective Adsorbing Material for Binding of Pyrrolizidine Alkaloids in Herbal Extracts, Based on Molecular Group Imprinting.

Pyrrolizidine alkaloids are secondary plant constituents that became a subject of public concern because of their hepatotoxic, pneumotoxic, genotoxic, and cytotoxic effects. Due to disregardful harvesting and/or contamination with pyrrolizidine alkaloid-containing plants, there is a high risk of ingesting these substances with plant extracts or natural products. The limit for the daily intake was set to 0.007 µg/kg body weight. If contained in an extract, cleanup methods may help to minimize the pyrrolizidine alkaloid concentration. For this purpose, a material for depleting pyrrolizidine alkaloids in herbal preparations was developed based on the approach of molecular imprinting using monocrotaline. Molecular imprinted polymers are substances with specific binding characteristics, depending on the template used for imprinting. By means of group imprinting, only one molecule is used for creating selective cavities for many molecular pyrrolizidine alkaloid variations. Design of Experiment was used for the development using a 25 screening plan resulting in 64 polymers (32 MIPs/32 NIPs). Rebinding trials revealed that the developed material can compete with common cation exchangers and is more suitable for depleting pyrrolizidine alkaloids than C18- material. Matrix trials using an extract from Chelidonium majus show that there is sufficient binding capacity for pyrrolizidine alkaloids (80%), but the material is lacking in selectivity towards pyrrolizidine alkaloids in the presence of other alkaloids with similar functional groups such as berberine, chelidonine, and coptisine. Beyond this interaction, the selectivity could be proven for other structurally different compounds on the example of chelidonic acid.

Sanguinarine in Chelidonium majus induced antifeeding and larval lethality by suppressing food intake and digestive enzymes in Lymantria dispar.

Our previous studies had identified that both crude extracts and total alkaloid from Chelidonium majus exerted a significant antifeeding and larval lethality on Lymantria dispar. Moreover, sanguinarine, chelidonine, berberine hydrochloride and coptisine were the main alkaloid in C. majus exerting toxicity to L. dispar. In this paper, we evaluated the insecticidal and antifeeding activities of each alkaloid on the 3rd instar L. dispar larvae by bioassay. Meanwhile, the effects of alkaloids from C. majus on the activities and mRNA levels of three main digestive enzymes in L. dispar larvae were investigated. The results indicated that sanguinarine possessed the strongest insecticidal activity with a LD50 value of 4.963 µg/larva, and the coptisine showed little lethality to 3 rd instar L. dispar larvae among four alkaloids from C. majus. The insecticidal capacity of four alkaloids on 3rd instar L. dispar larvae was in the following decreasing order of sanguinarine > chelidonine > berberine hydrochloride > coptisine. Similarly, except coptisine, the other three alkaloids significantly reduced food intakes of third instar L. dispar larvae and suppressed activities of three digestive enzymes (α-amylase, lipase and total protease) simultaneously. Finally, qRT-PCR analysis revealed that the transcriptions of α-amylase, lipase and serine protease were affected by sanguinarine. Especially, at 48 h after treatment, the mRNA expressions of those digestive enzymes were significantly suppressed by sanguinarine. In conclusion, we suggested that alkaloids from C. majus induced antifeeding and larval lethality on L. dispar larvae by suppressing food intake and digestive enzymes in L. dispar. Our findings provide a novel insight into evaluating the antifeeding and insecticidal properties of C. majus, which afford a new strategy for integrated pest management programs as well.