Multiscale analysis of the contents of palmatine in the Nature populations of Phellodendron amurense in Northeast China

Palmatine is a valuable ingredient in Chinese medicine that is produced by Phellodendron amurense Rupr. The contents of palmatine content in root bark, trunk bark, perennial branch bark, annual branches, and leaves of the trees with different ages and geographies in Northeast China were measured by high-performance liquid chromatography. The contents of palmatine in the barks of root, trunk, and perennial branch were significantly higher than those in annual branches and leaves. The contents of palmatine in trunk bark and root bark from Lesser Khingan Mountains increased with age, which is significantly opposite to other three vegetation types. The contents of palmatine in perennial branch bark, annual bark and leaves had no significant reg- ularity. Moreover, the contents of palmatine in samples of root bark, trunk bark, perennial branch bark and annual bark varied significantly with latitude. The nature populations of P. amurense growing at low latitude contained significantly more palmatine than those growing at high latitude. These results provide a scientific basis for the reasonable cultivation and efficient utilization of P. amurense.

Simultaneous Determination of Six Components in Cortex Phellodendri by HPLC

[Objectives]This study was conducted to establish the method for simultaneous determination of six active components.[Methods]Simultaneous determination of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine in Cortex Phellodendri was carried out by HPLC with a Diamonsil C18(4.6 mm×250 mm,5μm)column was used.The mobile phase was acetonitrile-water(1‰acetic acid,2 mmol ammonium acetate)solution in gradient elution.The detection wavelength was set at 280 nm,and the column temperature was kept at 25℃and the flow rate was 1 ml/min.[Results]The linear ranges of chlorogenic acid,phellodendrine,magnoflorine,jatrorrhizine,palmatine and berberine were 20.00-320.00,18.75-130.00,25.00-200.00,5.00-100.00,20.00-200.00,and 0.09-1.80 mg/L,respectively.The average recovery was 98.1%,99.4%,97.5%,97.3%,104.0%,and 98.5%,respectively;and the RSDs were 0.5%,0.6%,0.8%,1.0%,1.4%,and 0.9%,respectively.[Conclusions]The method is convenient,stable,reliable and suitable for quality control of Cortex Phellodendri.

Determination of Pesticide Residue Cartap Using a Sensitive Fluorescent Probe

The insecticide cartap （CP） is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine （PAL） can react with cucurbit[7]uril （CB[7]） to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values （AF） showed good linear relationship with cartap concentrations from 0.009 to 2.4 ~tg mL-~ with a detection limit 0.0029 ~tg mE-x. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the guest were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, xH NMR and molecular modeling calculations.

Synthesis,Crystal Structure and Antibacterial Activity of Ammonium Bromide

The new title compound N-（2-hydroxy ethyl） tetrahydropalmatine ammonium bromide has been synthesized starting from palmatine hydrochloride.The structure of the product was confirmed by 1H NMR,MS（ESI） and single-crystal X-ray diffraction.The title compound crystallizes in the triclinic system,space group P1 with a = 10.5887（11）,b = 10.8652（9）,c = 12.0914（12） ,β = 84.808（9）o,V = 1253.3（2） A^3,Z = 2,Dc = 1.355 g/cm^3,F（000） = 530,μ = 1.680 mm-1,the final R = 0.0833 and w R = 0.2371 for 5112 observed reflections（I 〉 2A（I））.X-ray analysis indicates that the two planar parts（C（2） C（3） C（4） C（5） C（6） C（7） N（1） C（20） C（21） C（21）） and（C（7） C（8） C（9） C（10） C（12） C（14） N（15） C（16） C（17）） are not coplanar,with the dihedral angles to be 67.9°.Weak interactions mainly between O（5）–H（5）···O from two water molecules and O（5）···Br are observed.

Simultaneous Determination of Effective Components of Gegen Qinlian Tablets by HPLC

[Objectives]To establish a HPLC method for the simultaneous determination of 14 characteristic components in Gegen Qinlian tablets and the content of Gegen Qinlian tablets in 11 manufacturers.[Methods]A Inertsil ODS-3(250 mm×4.6 mm,5μm)reversed-phase high performance liquid chromatography column was used with acetonitrile-0.02 mol/L ammonium acetate+0.03%triethylamine solution(adjusted with glacial acetic acid to pH of 4.3)as the mobile phase for gradient elution at a flow rate of 1.0 mL/min.The determination wavelength of 8 components(puerarin,daidzin,liquiritin,baicalin,wogonoside,daidzein,ammonium glycyrrhizinate,baicalein)was 250 nm;the determination wavelength of wogonoside was 280 nm;the determination wavelength of 5 components(epierberine,jatrorrhizine hydrochloride,coptisine,palmatine hydrochloride and berberine hydrochloride)was 346 nm.[Results]There was a good linear relationship between the injection volume of puerarin,daidzin,liquiritin,baicalin,wogonoside,epierberine,jatrorrhizine hydrochloride,coptisine,daidzein,palmatine hydrochloride,ammonium glycyrrhizinate,berberine hydrochloride,baicalein and wogonin and peak area(r>0.9990)in the range of 146.26-5850.24,24.13-965.04,18.45-738.00,79.18-3167.32,9.57-382.80,4.76-190.40,2.57-102.80,13.41-536.40,10.60-424.00,11.33-453.22,12.08-483.20,46.73-1869.25,20.28-811.20,12.11-484.50 ng,respectively;the average recovery rates(n=6)were 2.18%,1.79%,1.81%,1.68%,2.27%,2.13%,1.96%,1.07%,0.93%,0.61%,2.92%,0.77%,2.79%and 0.62%,respectively;the precision,repeatability and stability were good,and the RSD was less than 3%.This method was used to determine 16 batches of Gegen Qinlian tablets produced by 11 enterprises.Wogonoside was not detected in a lot of samples,but 14 components were detected for other enterprises,but the content was different.[Conclusions]The method was accurate and feasible and could be used for the overall quality control of this variety.

Screening the Synergistic Components of Acetylcholinesterase Inhibition from Phellodendron Bark Based on Fingerprint-Activity Relationship Modeling

Objective:Phellodendron chinense(PC)bark and Phellodendron amurense(PA)bark are two herbal medicines recorded in the Chinese Pharmacopoeia(2020 edition)that are easily mistaken for one another.In this study,the chemical constituents of PC and PA were compared using chromatographic fingerprints,and the potential synergistic acetylcholinesterase(ACh E)inhibitor components were screened based on the correlation of fingerprint activity.Materials and Methods:Chromatographic fingerprints based on high-performance liquid chromatography were developed for the analysis and comparison of chemical compounds in PC and PA samples.The ACh E inhibitory activity of PC and PA was determined using the Ellman method.Subsequently,the contribution of the characterized alkaloids in PC and PA to the overall ACh E inhibition was modeled using partial least squares regression(PLSR).Results:The total alkaloid content in PC was higher than that in PA,which causes PC to have stronger anti-ACh E activity.Overall,13 and 20 common peaks were identified in the PC and PA samples,respectively.Among them,berberine(BER)was the dominant alkaloid in PC,which covered more than 65%of the total peak area in PC,but only approximately 25%of that in PA,indicating that the chemical composition is different between PC and PA.The spectrum–effect analysis based on PLSR and the correlation analysis showed that the BER-palmatine(PAL)and BER-jatrorrhizine(JAT)pairs have a synergistic inhibitory effect on ACh E activity.Conclusions:A high-performance chromatographic fingerprint was established to distinguish PC and PA.The efficacy-associated markers were screened,including the pairs of BER-PAL and BER-JAT with anti-ACh E activity,and the findings may assist with the quality control of PA and PC.

Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method

The determination method of L-phenylalartine （LPA） by fluorescence quenching was developed. The assay was based on the combination of the cucurbit[7]uril （CB [7]） with palmatine hydrochloride （PAL） reaction. In the presence of CB [7], the fluorescence of PAL was quenched by LPA which can be employed to detect LPA. Under the optimal conditions, a linear range 3.63 ×10^-8- 9.68 ×10^-6 mol/L and a detection limit 1.27 ×10^-8 mol/L of LPA were obtained. The relative standard deviation （R.S.D） was 1.8% obtained from a series of 11 standards each containing 6.05 ×10^-6 mol/L of LPA. This paper also discusses the mechanism of fluorescence indicator probe.