Deciphering the synergistic network regulation of active components from SiNiSan against irritable bowel syndrome via a comprehensive strategy: Combined effects of synephrine, paeoniflorin and naringin.

BACKGROUND: SiNiSan (SNS) is an ancient Chinese herbal prescription, and the current clinical treatment of irritable bowel syndrome (IBS) is effective. In the previous study of the research team, the multi-functional co-synergism of SNS against IBS was presented. Some potential drug targets and candidate ligands were predicted. PURPOSE: This study attempts to explore the crucial ingredient combinations from SNS formula and reveal their synergistic mechanism for IBS therapy. MATERIALS AND METHODS: In present study, a comprehensive strategy was performed to reveal IBS related pathways and biological modules, and explore synergistic effects of the ingredients, including ADME (absorption, distribution, metabolism, excretion) screening, Text mining, Venn analysis, Gene ontology (GO) analysis, Pathway cluster analysis, Molecular docking, Network construction and Experimental verification in visceral hypersensitivity (VHS) rats. RESULTS: Three compressed IBS signal pathways were derived from ClueGO KEGG analysis of 63 IBS genes, including Neuroactive ligand-receptor interaction, Inflammatory mediator regulation of TRP (transient receptor potential) channels and Serotonergic synapse. A multi-module network, composed of four IBS therapeutic modules (psychological, inflammation, neuroendocrine and cross-talk modules), was revealed by Target-Pathway network. Nine kernel targets were considered closely associated with the IBS pathways, including ADRA2A, HTR2A, F2RL1, F2RL3, TRPV1, PKC, PKA, IL-1Β and NGF. In silico analysis revealed that three crucial ingredients (synephrine, paeoniflorin and naringin) were assumed to coordinate the network of those IBS therapeutic modules by acting on these kernel targets in the important pathways. In vivo experimental results showed that the crucial ingredient combinations synergistically affected the expressions of the kernel biological molecules, and improved the minimum capacity threshold of AWR in VHS rats. CONCLUSION: The study proposes the important IBS associated pathways and the network regulation mechanisms of the crucial ingredients. It reveals the multi-target synergistic effect of the crucial ingredient combinations for the novel therapy on IBS.

Ultrasound-assisted aqueous two-phase extraction of synephrine, naringin, and neohesperidin from Citrus aurantium L. fruitlets.

The ultrasound-assisted aqueous two-phase extraction (UA-ATPE) was first employed to develop an effective technique for simultaneous extraction and preliminary purification of synephrine, naringin, and neohesperidin from Citrus aurantium L. fruitlets. Five types of ethanol/salts of aqueous two-phase system (ATPS) were investigated and then the extraction conditions were further optimized using single-factor experiments and response surface methodology (RSM) via Box-Behnken Design (BBD). The optimum process parameters were concluded as follows: 20.60% (w/w) K2CO3, 27% (w/w) ethanol, solvent-to-material ratio of 45.17:1 (g:g), 120-mesh particle size of fruitlets powder, extraction temperature of 50 °C, extraction time of 30 min, and ultrasonic power of 80 W. Under these conditions, the extraction yields of synephrine, naringin, and neohesperidin were up to 11.17 mg/g, 7.39 mg/g, and 89.27 mg/g, respectively. The yield of neohesperidin extracted by the optimal UA-ATPE was over eight times higher than that extracted by the ultrasound-assisted extraction (UAE) using conventional solvents, and the total yield of target compounds was over twice higher while the impurity content in the extract was much lower. Therefore, UA-ATPE appeared to be a highly effective and promising approach for the extraction of synephrine, naringin, and neohesperidin from C. aurantium fruitlets.

Acute p-synephrine ingestion increases whole-body fat oxidation during 1-h of cycling at Fatmax.

PURPOSE: p-Synephrine, the principal alkaloid of bitter orange (Citrus aurantium), is widely used in dietary supplements for weight loss due to its purported effect of increasing fat oxidation. However, there is a paucity of scientific information about its effectiveness in enhancing fat oxidation during exercise. The aim of this investigation was to determine the effect of an acute dose of p-synephrine on substrate oxidation during prolonged and constant intensity exercise. METHODS: In a double-blind and randomized experiment, 14 healthy subjects performed two acute experimental trials after ingesting either p-synephrine (3 mg kg-1) or a placebo (cellulose). Energy expenditure and fat oxidation rates were continuously measured by indirect calorimetry during 1 h of continuous cycling at Fatmax, the intensity that induces maximal fat oxidation rate. RESULTS: In comparison to the placebo, energy expenditure during 1 h of cycling remained unchanged with p-synephrine (698 ± 129 vs. 686 ± 123 kcal, P = 0.08). However, p-synephrine increased whole-body fat oxidation (33.6 ± 10.4 vs. 37.3 ± 9.8 g, P < 0.01) while also reducing carbohydrate oxidation (99.5 ± 30.4 vs. 85.0 ± 28.4 g, P < 0.01). However, the magnitude of the shift on substrate oxidation induced by p-synephrine was small. CONCLUSION: Acute ingestion of p-synephrine augments fat oxidation during prolonged and constant-intensity exercise.

Co-Existence of Hypertensive and Anti-Hypertensive Constituents, Synephrine, and Nobiletin in Citrus unshiu Peel.

A single herb can contain multiple constituents with diverse bioactivities. We found that the extract of Citrus unshiu peel (CUP), induced abnormal vasoconstriction responses on the freshly isolated rat aortic rings in vitro. CUP stimulated the vasoconstriction alone, and it suppressed the phenylephrine-stimulated vasoconstriction. We studied the reasons behind this abnormal vasoconstriction pattern. Major constituents of CUP were determined and evaluated for their vaso-activities. Notably, synephrine, a contractile agonist, and nobiletin, newly identified to have anti-contractile activity co-existed in CUP. Synephrine and nobiletin competitively blocked or activated the same contractile targets resulting in contradicting and abnormal vasoconstriction responses. Accordingly, the vasoconstriction pattern varies significantly depending on the relative contents of synephrine and nobiletin in CUP. Interestingly, this response pattern could be observed with another plant extract, Acorus gramineus Sol. Collectively, we demonstrated that active ingredients with contradicting bioactivities could co-exist in a single plant extract, interact and produce abnormal response patterns in bioassay, which would give an important insight into the interpretation of unusual activity patterns induced by plant extracts.

Separation of Synephrine Enantiomers in Citrus Fruits by a Reversed Phase HPLC after Chiral Precolumn Derivatization.

Racemic synephrine, which was transformed into diastereomers by derivatization with 2,3,4,6-tetra-O-acetyl-ß-D-glucopyranosil isothiocyanate, was resolved by a reversed phase HPLC with UV detection at 254 nm. The total contents of synephrine enantiomers in citrus fruit samples were exocarp > mesocarp > endocarp > sarcocarp, suggesting that synephrine content of outer side of citrus fruits was higher than that of the inner side. (R)-Synephrine was detected in exocarp of eleven fresh citrus fruits, except for lemon, lime, and grapefruit samples. (S)-Synephrine was determined in the exocarp of four citrus fruits (mikan, orange, bitter orange, and ponkan samples) and the ratio of (S)-synephrine to total synephrine was 0.5 - 0.9%. The racemization of (R)-synephrine in aqueous solution during heating at 100°C was also examined. An increase in the heating time brought about an increase in the (S)-synephrine content in a linear fashion. The racemization was found to be significantly reduced by the addition of D-fructose, D-maltose, D-glucose, D-mannose or D-galactose, but not D-sucrose or D-mannitol. It is suggested that the reducibility of sugars may result in the inhibition of racemization.

The solvation properties and effect of d-fructose on the taste behavior of Citrus aurantium active components in aqueous solutions.

The densities and viscosities of synephrine hydrochloride and octopamine hydrochloride aqueous solutions were determined. Apparent molar volumes, apparent molar volume at infinite dilution, viscosity B-coefficients and hydration number were calculated, and it was found that synephrine hydrochloride acts as a better structure maker than octopamine hydrochloride in aqueous solutions. The densities of the investigated salts were measured in aqueous d-fructose solutions, and the corresponding apparent molar volumes of transfer at infinite dilution were determined. Its taste behavior was discussed based on the calculated values for apparent specific volume and intrinsic viscosity. Molecular dynamics simulations and radial distribution functions were applied in order to understand the nature of the interactions and water structuring in the studied systems. The change in taste behavior was observed with increasing concentration of the cosolute, and it was found that the addition of sugar increases the bitterness of the solution. From a molecular docking study on the bitter receptor TAS2R38, the strongest interactions for synephrine-HCl were noted causing the most bitter taste.

Study to Probe Subsistence of Host-Guest Inclusion Complexes of α and ß-Cyclodextrins with Biologically Potent Drugs for Safety Regulatory Dischargement.

Host-guest interaction of two significant drugs, phenylephrine hydrochloride and synephrine with α and ß-cyclodextrins were studied systematically. Initially two simple but reliable physicochemical techniques namely conductance and surface tension were employed to find out saturation concentration for the inclusion and its stoichiometry. The obtained 1:1 stoichiometry was further confirmed by two spectrometric methods, UV-Vis study and spectrofluorimetry. Significant shifts in IR stretching frequency also support the inclusion process. Relative stabilities of the inclusion complexes were established by the association constants obtained from UV-Vis spectroscopic measurements, program based mathematical calculation of conductivity data. Calculations of the thermodynamic parameters dictates thermodynamic feasibility of the inclusion process. Spectrofluorometric measurement scaffolds the UV-Vis spectroscopic measurement validating stability of the ICs once again. Mass spectroscopic measurement gives the molecular ion peaks corresponding to the inclusion complex of 1:1 molar ratio of host and guest molecules. The mechanism of inclusion was drawn by 1H-NMR and 2D ROESY spectroscopic analysis. Surface texture of the inclusion complexes was studied by SEM. Finally, the cytotoxic activities of the inclusion complexes were analyzed and found, Cell viability also balances for non-toxic behavior of the ICs. Moreover, all the studies reveal the formation of inclusion complexes of two ephedra free, alternatively emerging drugs (after their banned product having ephedra) SNP, PEH with α and ß-CD which enriches the drug delivery system with their regulatory release without any chemical modification.

Synephrine Hydrochloride Suppresses Esophageal Cancer Tumor Growth and Metastatic Potential through Inhibition of Galectin-3-AKT/ERK Signaling.

A library consisting of 429 food-source compounds was used to screen the natural products with anticancer properties in esophageal squamous cell carcinoma (ESCC). We demonstrated for the first time that synephrine, an active compound isolated from leaves of citrus trees, markedly suppressed cell proliferation (inhibition rate with 20 µM synephrine at day 5:71.1 ± 5.8% and 75.7 ± 6.2% for KYSE30 and KYSE270, respectively) and colony formation (inhibition rate with 10 µM synephrine: 86.5 ± 5.9% and 82.3 ± 4.5% for KYSE30 and KYSE270, respectively), as well as migration (inhibition rate with 10 µM synephrine: 76.9 ± 4.4% and 62.2 ± 5.8% for KYSE30 and KYSE270, respectively) and invasion abilities (inhibition rate with 10 µM synephrine: 73.3 ± 7.5% and 75.3 ± 3.4% for KYSE30 and KYSE270, respectively) of ESCC cells in a dose-dependent manner, without significant toxic effect on normal esophageal epithelial cells. Mechanistically, quantitative proteomics and bioinformatics analyses were performed to explore the synephrine-regulated proteins. Western blot and qRT-PCR data indicated that synephrine may downregulate Galectin-3 to inactivate AKT and ERK pathways. In addition, we found that the sensitivity of ESCC to fluorouracil (5-FU) could be enhanced by synephrine. Furthermore, in vivo experiments showed that synephrine had significant antitumor effect on ESCC tumor xenografts in nude mice (inhibition rate with 20 mg/kg synephrine is 61.3 ± 20.5%) without observed side effects on the animals. Taken together, synephrine, a food-source natural product, may be a potential therapeutic strategy in ESCC.

An Overview on Citrus aurantium L.: Its Functions as Food Ingredient and Therapeutic Agent.

Citrus aurantium L. (Rutaceae), commonly known as bitter orange, possesses multiple therapeutic potentials. These biological credentials include anticancer, antianxiety, antiobesity, antibacterial, antioxidant, pesticidal, and antidiabetic activities. The essential oil of C. aurantium was reported to display marked pharmacological effects and great variation in chemical composition depending on growing locations but mostly contained limonene, linalool, and ß-myrcene. Phytochemically, C. aurantium is rich in p-synephrine, an alkaloid, and many health-giving secondary metabolites such as flavonoids. Animal studies have demonstrated a low affinity of p-synephrine for adrenergic receptors and an even lower affinity in human models. The present review focuses on the different biological activities of the C. aurantium in animal and human models in the form of extract and its pure secondary metabolites. Finally, it is concluded that both the extract and isolated compounds have no unwanted effects in human at therapeutic doses and, therefore, can confidently be used in various dietary formulations.

Actions of p-synephrine on hepatic enzyme activities linked to carbohydrate metabolism and ATP levels in vivo and in the perfused rat liver.

p-Synephrine is one of the main active components of the fruit of Citrus aurantium (bitter orange). Extracts of the bitter orange and other preparations containing p-synephrine have been used worldwide to promote weight loss and for sports performance. The purpose of the study was to measure the action of p-synephrine on hepatic enzyme activities linked to carbohydrate and energy metabolism and the levels of adenine mononucleotides. Enzymes and adenine mononucleotides were measured in the isolated perfused rat liver and in vivo after oral administration of the drug (50 and 300 mg/kg) by using standard techniques. p-Synephrine increased the activity of glycogen phosphorylase in vivo and in the perfused liver. It decreased, however, the activities of pyruvate kinase and pyruvate dehydrogenase also in vivo and in the perfused liver. p-Synephrine increased the hepatic pools of adenosine diphosphate and adenosine triphosphate. Stimulation of glycogen phosphorylase is consistent with the reported increased glycogenolysis in the perfused liver and increased glycemia in rats. The decrease in the pyruvate dehydrogenase activity indicates that p-synephrine is potentially capable of inhibiting the transformation of carbohydrates into lipids. The capability of increasing the adenosine triphosphate-adenosine diphosphate pool indicates a beneficial effect of p-synephrine on the cellular energetics.

[Exploring correlation between molecular state and nanofiltration mass transfer process of synephrine from Citrus aurantium].

Based on the solution-diffusion effect and the charge effect theory in nanofiltration separation, the correlation between initial concentration and mass transfer coefficient was constructed to establish a mathematic model of synephrine in mass transfer process and verify its applicability. The experimental results showed that there was a linear relationship between operation pressure and membrane flux. Meanwhile, the membrane flux was gradually decayed with the increase of solute concentration. Besides, mass transfer coefficient and initial concentration of synephrine showed power function correlation with each other by solution-diffusion effect and the charge effect, and the regression coefficients were greater than 0.9. The mass transfer coefficient of dissociation synephrine was less than that in the state of free and free-dissociation. Moreover, on the basis of power function relationship between mass transfer coefficient and initial concentration, the results showed that the predicted rejections of synephrine from Citrus aurantium water extract by use of the mathematical model approximated well to real ones, verifying that the model was practical and feasible. The unclear separation mechanism of nanofiltration for alkaloids was clarified preliminary by the predicted model of nanofiltration separation with synephrine as the example, providing theoretical and technical support for nanofiltration separation, especially for traditional Chinese medicine with alkaloids.

Cardiovascular Safety of Oral p-Synephrine (Bitter Orange) in Healthy Subjects: A Randomized Placebo-Controlled Cross-over Clinical Trial.

Bitter orange (Citrus aurantium) extract and its primary protoalkaloid p-synephrine are widely consumed in combination with multiple herbal ingredients for weight management and sports performance. p-Synephrine is also present in juices and foods derived from a variety of Citrus species. Questions exist regarding the safety of p-synephrine because of structural similarities with other biogenic amines. This study assessed the cardiovascular (stimulatory) effects of bitter orange extract (49-mg p-synephrine) given to 18 healthy subjects (nine men and nine women) in a double-blinded, placebo-controlled cross-over study. Heart rates, blood pressures, and electrocardiograms were determined at baseline, 30, 60, 90 min, 2, 4 , 6, and 8 h. Blood samples were drawn at baseline, 2 h and 8 h for serum chemistries, blood cell counts, and p-synephrine and caffeine levels. No significant changes occurred in electrocardiograms, heart rates, systolic blood pressure, blood chemistries, or blood cell counts at any time point in either control or p-synephrine treated group. A small (4.5 mmHg) decrease in diastolic blood pressure occurred in the p-synephrine treated group at 60 min. No adverse effects were reported. Caffeine ingestion varied markedly among the participants. p-Synephrine does not act as a stimulant at the dose used. Copyright © 2016 John Wiley & Sons, Ltd.

Fast hepatic biotransformation of p-synephrine and p-octopamine and implications for their oral intake.

Citrus aurantium (bitter orange) extracts have been used in products for weight management and sports performance. These extracts contain large amounts of p-synephrine and much smaller amounts of p-octopamine. Both protoalkaloids exert lipolytic and glycogenolytic activities at similar concentrations. The biotransformation of p-synephrine and p-octopamine is not as well-known as those of other adrenergic amines. For this reason transformation of these amines was investigated in the isolated perfused liver. Special attention was devoted to the single pass extraction of each compound as well as to the kinetics of uptake. The assay of the amines in the outflowing perfusate was done by means of high performance liquid chromatography (HPLC). The single pass extraction of p-synephrine was higher than 90% at a portal concentration of 10 µM. It declined with the concentration, but was still around 30% at the concentration of 500 µM. At low concentrations (10-50 µM) the decreasing sequence of single pass extractions was p-synephrine > p-octopamine ≈ epinephrine > norepinephrine. Rates of uptake versus p-synephrine concentration resulted in a Michaelis-Menten type of relationship, with a KM value of 290.7 ± 32.1 µM and a Vmax of 0.762 ± 0.042 µmol min(-1) g(-1). The rates of uptake of p-octopamine did not present clear saturation and could be approximated by a linear relationship with a first order rate constant of 1.5 min(-1). The rapid hepatic transformation of p-synephrine and p-octopamine means that their concentration in the portal vein exceeds that in the systemic circulation during absorption. Their metabolic effects will, thus, be exerted predominantly in the liver.

Synephrine inhibits eotaxin-1 expression via the STAT6 signaling pathway.

Citrus contain various flavonoids and alkaloids that have multiple biological activities. It is known that the immature Citrus contains larger amounts of bioactive components, than do the mature plants. Although Citrus flavonoids are well known for their biological activities, Citrus alkaloids have not previously been assessed. In this study, we identified synephrine alkaloids as an active compound from immature Citrus unshiu, and investigated the effect of synephrine on eotaxin-1 expression. Eotaxin-1 is a potent chemoattractant for eosinophils, and a critical mediator, during the development of eosinophilic inflammation. We found that synephrine significantly inhibited IL-4-induced eotaxin-1 expression. This synephrine effect was mediated through the inhibition of STAT6 phosphorylation in JAK/STAT signaling. We also found that eosinophil recruitment induced by eotaxin-1 overexpression was inhibited by synephrine. Taken together, these findings indicate that inhibiting IL-4-induced eotaxin-1 expression by synephrine occurs primarily through the suppression of eosinophil recruitment, which is mediated by inhibiting STAT6 phosphorylation.

A separation of tyramine on a 2-(4-methoxyphenyl)ethylamine imprinted polymer: an answer from theoretical and experimental studies.

A 2-(4-methoxyphenyl)ethylamine imprinted polymer (MIP) was successfully applied for the selective separation of tyramine. A computational analysis was used to predict the affinity of the polymer matrix towards tyramine and a preliminary experimental evaluation was made for the target analyte. Then the experimental analysis of polymer towards tyramine was continued. The binding sites were characterized with employment of the Langmuir and Freudlich models. After the optimization of solid phase extraction towards tyramine, the most appropriate systems for the extraction steps were chosen: methanol-water 85:15 v/v for the loading and the washing as well as 0.04 M aq. ammonium acetate-methanol 30:70 v/v for the elution steps. The biogenic compounds as tryptamine, serotonin, octopamine, synephrine, and l-tyrosine were used for the selectivity study on the basis of binding capacities of the analytes on the imprinted and the non-imprinted polymers. The theoretical approach to obtained results allowed to explain the adsorption selectivity of the tested polymer. Finally, the complex matrix of bovine serum albumin was used to show the usefulness of imprinted material for bioanalysis. The obtained recoveries showed the superiority of MIP over the commercial sorbent C18. Total recoveries of tyramine from spiked bovine serum albumin sample were determined as: 95±2%, 14±3%, and 1.9±0.4% for the imprinted, non-imprinted, and commercial C18 sorbents, respectively.

3D-printed and CNC milled flow-cells for chemiluminescence detection.

Herein we explore modern fabrication techniques for the development of chemiluminescence detection flow-cells with features not attainable using the traditional coiled tubing approach. This includes the first 3D-printed chemiluminescence flow-cells, and a milled flow-cell designed to split the analyte stream into two separate detection zones within the same polymer chip. The flow-cells are compared to conventional detection systems using flow injection analysis (FIA) and high performance liquid chromatography (HPLC), with the fast chemiluminescence reactions of an acidic potassium permanganate reagent with morphine and a series of adrenergic phenolic amines.

A novel molecularly imprinted polymer of the specific ionic liquid monomer for selective separation of synephrine from methanol-water media.

A novel molecularly imprinted polymer (MIP) using the specific ionic liquid (i.e. 1-vinyl-3-carboxymethylimidazolium bromide, 1-vinyl-3-carboxyethylimidazolium bromide, 1-viny-3-carboxybutylimidazolium bromide, or 1-vinyl-3-carboxypentylimidazolium bromide) as functional monomer was prepared via precipitation polymerization, which can be used to selectively separate synephrine (SYN) from methanol-water media. Ionic liquids are facile to be designed with varying the cation or anion, which enables the specific ionic liquid to be effectively designed to be a functional monomer for the preparation of MIP. The MIP showed a good selectivity and high adsorption capacity for SYN in methanol-water media. The adsorption process could be described by the pseudo-first-order model, which meant that the adsorption kinetics described a diffusion-controlled process. The equilibrium data fitted well to the Freundlich model, indicating multilayer adsorption. Finally, the MIP were successfully applied as sorbent to selectively enrich and separate SYN from the extracts of Aurantii Fructus Immaturus with a relatively high recovery (80-90%).

Conformational analysis of octopamine and synephrine in the gas phase.

Four and six conformers of the neurotransmitters octopamine and synephrine, respectively, have been identified in the gas phase using a laser ablation device in combination with a molecular-beam Fourier transform microwave spectrometer operating in the 4-10 GHz frequency range. The identification of all of the conformers was based on a comparison of the experimental rotational and (14)N quadrupole coupling constants with those predicted by ab initio calculations, as well as the relative values of their electric dipole moment components. The conformational preferences have been rationalized in terms of the various intramolecular forces operating in the different conformers of the studied molecules. All observed species are characterized by an intramolecular hydrogen bond of the type O-H···N established in the side chain of the neurotransmitters, which adopts an extended disposition in their most stable forms. For conformers with a folded side chain, an extra N-H···π hydrogen-bond-type interaction is established between the amino group and the π system of the aromatic ring.

Study of the photocatalytic transformation of synephrine: a biogenic amine relevant in anti-doping analysis.

The occurrence of some cases of positive results in anti-doping analysis of octopamine requires clarification as to whether its methylated derivative synephrine could be a metabolic precursor of octopamine itself. Synephrine is a natural phenylethylamine derivative present in some food supplements containing Citrus aurantium, permitted in sport regulations. A simulative laboratory study had been done using a photocatalytic process, to identify all possible main and secondary transformation products, in a clean matrix; these were then sought in biological samples obtained from three human volunteers and four rats treated with synephrine; the parent compound and its new potential metabolic products were investigated in human urine and rat plasma samples. The transformation of synephrine and octopamine and the formation of intermediate products were evaluated, adopting titanium dioxide as photocatalyst. Several products were formed and characterized using the HPLC-HRMS(n) technique. The main intermediates identified in these experimental conditions were compared with the major synephrine metabolites found in in vivo studies on rats and humans. Some more oxidized species, already formed in the photocatalytic process, were also found in urine and plasma samples of treated animals. These new findings could be of interest in further metabolism studies. The main photocatalytic pathway involving synephrine appears to be N-demethylation to give octopamine. On the contrary, we demonstrate the inconsistency of this reaction in both rat and human in vivo determinations, resulting in forensic importance.

Simultaneous determination of synephrine, arecoline, and norisoboldine in Chinese patent medicine Si-Mo-Tang oral liquid preparation by strong cation exchange high performance liquid chromatography.

CONTEXT: Chinese patent medicine Si-Mo-Tang oral liquid preparation (SMT) is composed of Aucklandia luppa Decne (Compositae), Citrus aurantium Linn (Rutaceae), Lindera aggregata (Sims) Kosterm (Lauraceae), and Areca catechu Linn (Arecaceae). Studies of SMT have been impeded due to the lack of quality control methods. OBJECTIVE: This study aimed to simultaneously determine three alkaloids including synephrine, arecoline, and norisoboldine in SMT for the first time. MATERIALS AND METHODS: A strong cation exchange (SCX) high performance liquid chromatography (HPLC) method was developed to simultaneously determine synephrine, arecoline, and norisoboldine in SMT, and was compared with ion-pairing chromatography using regular reversed-phase chromatography columns. System suitability parameters of synephrine, arecoline, and norisoboldine using the SCX chromatography column were investigated. RESULTS: Results demonstrated that good separations were achieved on an Agilent SCX (250 × 4.6 mm, 5 µm) column at 35 °C. The mobile phase consisting of methanol-0.2% phosphoric acid was delivered at a constant flow of 1.0 mL min(-1) and the eluent was monitored at 215 nm. The HPLC method showed good linearity for the examined concentration ranges of 2.55-255.0, 1.30-208.0, and 2.06-201.6 µg mL(-1) for synephrine, arecoline, and norisoboldine, respectively. The limits of quantification (S/N = 10) were 2.55, 1.30, and 2.06 µg mL(-1), the limits of detection (S/N = 3) were 1.53, 0.78, and 1.21 µg mL(-1), and average recoveries were 98.99, 95.63 and 99.04%, respectively, for synephrine, arecoline, and norisoboldine. DISCUSSION AND CONCLUSION: This method has been successfully applied to determine synephrine, arecoline, and norisoboldine in Chinese patent medicine SMT.