Facile separation and determination of Aconitine alkaloids in traditional Chinese medicines by CE with tris(2,2'-bipyridyl) ruthenium(II)-based electrochemiluminescence detection

A facile CE method coupled with tris(2,2'-bipyridyl) ruthenium(II)-based electrochemiluminescence [Ru(bpy)(3) (2+)] detection was developed for simultaneous determination of Aconitum alkaloids, i.e., hypaconitine (HA), aconitine (AC), and mesaconitine (MA) in baseline separation. The optimal separation of these Aconitum alkaloids was achieved in a fused-silica capillary column (50 cm x 25 microm id) with 30 mM phosphate solution (pH 8.40) as running buffer at 12 kV applied voltage. The three alkaloids can be determined within 10 min by a single run. The calibration curves showed a linear range from 2.0 x 10(-7) to 2.0 x 10(-5) M for HA, 3.4 x 10(-7) to 1.7 x 10(-5) M for AC, and 3.8 x 10(-7) to 1.9 x 10(-5) M for MA. The RSDs for all analytes were below 3.01%. Good linear relationships were found with correlation coefficients for all analytes exceeding 0.993. The detection limits were 2.0 x 10(-8) M for HA, 1.7 x 10(-7) M for AC, and 1.9 x 10(-7) M for MA under optimal conditions. This method was successfully applied to determine the three alkaloids in Aconitum plants.     

Alkaloids induce programmed cell death in bloodstream forms of trypanosomes (Trypanosoma b. brucei)

The potential induction of a programmed cell death (PCD) in Trypanosoma b. brucei by 55 alkaloids of the quinoline, quinolizidine, isoquinoline, indole, terpene, tropane, steroid, and piperidine type was studied by measuring DNA fragmentation and changes in mitochondrial membrane potential. For comparison, the induction of apoptosis by the same alkaloids in human leukemia cells (Jurkat APO-S) was tested. Several alkaloids of the isoquinoline, quinoline, indole and steroidal type (berberine, chelerythrine, emetine, sanguinarine, quinine, ajmalicine, ergotamine, harmine, vinblastine, vincristine, colchicine, chaconine, demissidine and veratridine) induced programmed cell death, whereas quinolizidine, tropane, terpene and piperidine alkaloids were mostly inactive. Effective PCD induction (EC(50) below 10 microM) was caused in T. brucei by chelerythrine, emetine, sanguinarine, and chaconine. The active alkaloids can be characterized by their general property to inhibit protein biosynthesis, to intercalate DNA, to disturb membrane fluidity or to inhibit microtubule formation.     

Antineoplastic Alkaloids From Chinese Medicinal Plants and Their Analogs

The Chinese medicinal plant-derived antineoplastic alkaloids and their analogs are reviewed with emphasis on those discovered from the authors' laboratory. The active compounds include camptothecin, colchicine, ellipticine, harringtonine, Vinca alkaloids, indirubin, (-)-sophocarpine, lycobetaine, monocrotaline, d-tetrandrine, indicine N-oxide, maytansine, aporphine type alkaloids, palmatine, murrapanine, emarginatine alkaloids, and the alkaloids from Securinega virosa. The compounds are discussed briefly with the recent advances concerning their antitumor activity, structure-activity relationships and mechanisms of action.     

Polymer fractionation using chromatographic column packed with novel regenerated cellulose beads modified with silane

Novel microporous beads with the particle size of about 90 microm were prepared, for the first time, from cellulose and konjac glucomannan (RC/KGM3) in 1.5 M NaOH/0.65 M thiourea aqueous solution by emulsification method. The microporous beads were then modified with silane to avoid the adsorption of polymers containing hydroxyl groups, coded as RC/KGM3-Si. A preparative size-exclusion chromatographic (SEC) column (500 mm x 20 mm) was packed with RC/KGM3-Si, and its exclusion limit and fractionation range of the stationary phase were, respectively, weight-average molecular masses (Mw) of 4.8 x 10(5) g/mol and 5.3 x 10(3)-4.8 x 10(5) g/mol for polystyrene in tetrahydrofuran. The preparative SEC column was used to fractionate poly(epsilon-caprolactone) (PCL, Mw = 8.31 x 10(4) g/mol polydispersity index d= 1.55) in tetrahydrofuran and a polysaccharide PC3-2 (Mw = 1.21 x 10(5) g/mol, d= 1.70) in 0.05 M NaOH aqueous solution, respectively. The Mw values of the fractions determined by analytical SEC combined with laser light scattering were from 1.2 x 10(4) to 1.84 x 10(5) for PCL and from 8.5 x 10(4) to 2.13 x 10(5) for PC3-2, as well as d from 1.2 to 1.5. The results indicated that the preparative SEC has good fractionation efficiency in both organic solvent and alkaline aqueous solution for the various polymers.     

Mechanism of immunosuppression by a murine non-specific suppressor T cell line, SB-1.

The mechanism of immunosuppression by a murine non-specific suppressor T cell clone (SB-1), which was established from concanavalin A (Con A)-activated murine spleen cells [Jpn. J. Exp. Med., 53, 139 (1983)], was investigated. SB-1-induced decrease of antigen non-specific plaque-forming cell (PFC) response was restored by the addition of 5 x 10(-6) M indomethacin, an inhibitor of cyclooxygenase. On the other hand, suppressive activity for antigen non-specific PFC response was found in the culture supernatant of SB-1 cells in the presence of proteose peptone-elicited macrophages. This induction of the suppressive activity was also inhibited by 5 x 10(-6) M indomethacin. Furthermore, 10(-5) M prostaglandine E2 (PGE2) was found to induce suppressive activity in the culture supernatant of SB-1 cells. 10(-5) M PGE2 did not suppress interleukin-2 (IL-2)-dependent proliferation of SB-1 cells, but increased a small quantity of protein synthesis and deoxyribonucleic acid (DNA) synthesis of SB-1 cells in the absence of IL-2. These results suggest that a cyclooxygenase product(s) such as PGE2 from macrophages may induce production of soluble suppressor factors in SB-1 cells. To characterize these suppressor factors, those in the culture supernatant of PGE2-stimulated SB-1 cells were partially purified by ammonium sulfate fractionation and sequential column chromatographies on diethylaminoethyl (DEAE)-cellulofine and Sephacryl S-200. Suppressor activities were eluted at the positions corresponding to the molecular masses of 10, 30, 70 and over 70 kilodalton (kDa) on Sephacryl S-200 column chromatography.(ABSTRACT TRUNCATED AT 250 WORDS)     

Acetylcholinesterase-inhibiting alkaloids from Zephyranthes concolor

The bulbs and aerial parts of Zephyranthes concolor (Lindl.) Benth. & Hook. f. (Amaryllidaceae), an endemic species to Mexico, were found to contain the alkaloids chlidanthine, galanthamine, galanthamine N-oxide, lycorine, galwesine, and epinorgalanthamine. Since currently only partial and low resolution (1)H-NMR data for chlidanthine acetate are available, and none for chlidanthine, its 1D and 2D high resolution (1)H- and (13)C-NMR spectra were recorded. Unambiguous assignations were achieved with HMBC, and HSQC experiments, and its structure was corroborated by X-ray diffraction. Minimum energy conformation for structures of chlidanthine, and its positional isomer galanthamine, were calculated by molecular modelling. Galanthamine is a well known acetylcholinesterase inhibitor; therefore, the isolated alkaloids were tested for this activity. Chlidanthine and galanthamine N-oxide inhibited electric eel acetylcholinesterase (2.4 and 2.6 × 10(-5) M, respectively), indicating they are about five times less potent than galanthamine, while galwesine was inactive at 10(-3) M. Inhibitory activity of HIV-1 replication, and cytotoxicity of the isolated alkaloids were evaluated in human MT-4 cells; however, the alkaloids showed poor activity as compared with standard anti-HIV drugs, but most of them were not cytotoxic.     

Binding behaviour and solubilisation of p-sulfonatocalixarenes to cinchona alkaloids

In this study, we investigated the binding behaviours of three water-soluble p-sulfonatocalixarenes with four cinchona alkaloids in aqueous and phosphate buffer solutions (pH 7.2 and 2.0). The complexation stability constants obtained by fluorescence titrations were comparatively discussed from several aspects: host cavity, pH effect and ionic strength. Among three hosts, p-sulfonatocalix[4]arene (SC4A) forms the most stable complexes with cinchona alkaloids, especially in acidic aqueous conditions. Furthermore, SC4A was elected as model drug carrier for cinchona alkaloids, where solubilisation by the complexation of SC4A and mimic release from the calixarene cavity in the presence of negatively charged micelles were initially studied.     

超临界二氧化碳萃取秋水仙碱（英文）

 利用超临界二氧化碳对秋水仙块根（经粉碎）中的秋水仙碱进行了萃取,采用高效液相色谱法对萃取出的秋水仙碱的质量分数进行了测定。实验选择40℃20～40MPa作为超临界苹取的操作条件,采用体积分数为95％的乙醇在索氏提取器中对样品进行了对比苹取实验。结果表明:不加浸泡剂进行浸泡处理的样品中的秋水仙碱很难被超临界二氧化碳萃取,在40℃,35MPa条件下,消耗1．28mol的二氧化碳只得到3％的萃取率。加入极少量的有机溶剂浸泡处理样品15min后再进行超临界萃取,可以极大程度地提高秋水仙碱的萃取率。     

Marine Brominated Tyrosine Alkaloids as Promising Inhibitors of SARS-CoV-2

There have been more than 150 million confirmed cases of SARS-CoV-2 since the beginning of the pandemic in 2019. By June 2021, the mortality from such infections approached 3.9 million people. Despite the availability of a number of vaccines which provide protection against this virus, the evolution of new viral variants, inconsistent availability of the vaccine around the world, and vaccine hesitancy, in some countries, makes it unreasonable to rely on mass vaccination alone to combat this pandemic. Consequently, much effort is directed to identifying potential antiviral treatments. Marine brominated tyrosine alkaloids are recognized to have antiviral potential. We test here the antiviral capacity of fourteen marine brominated tyrosine alkaloids against five different target proteins from SARS-CoV-2, including main protease (M^pro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H). These marine alkaloids, particularly the hexabrominated compound, fistularin-3, shows promising docking interactions with predicted binding affinities (S-score = −7.78, −7.65, −6.39, −6.28, −8.84 Kcal/mol) for the main protease (M^pro) (PDB ID: 6lu7), spike glycoprotein (PDB ID: 6VYB), nucleocapsid phosphoprotein (PDB ID: 6VYO), membrane glycoprotein (PDB ID: 6M17), and non-structural protein 10 (nsp10) (PDB ID: 6W4H), respectively, where it forms better interactions with the protein pockets than the native interaction. It also shows promising molecular dynamics, pharmacokinetics, and toxicity profiles. As such, further exploration of the antiviral properties of fistularin-3 against SARS-CoV-2 is merited.     

Lycoperoside H,a Tomato Seed Saponin,Improves Epidermal Dehydration by Increasing Ceramide in the Stratum Corneum and Steroidal Anti-Inflammatory Effect

Tomatoes are widely consumed, however, studies on tomato seeds are limited. In this study, we isolated 11 compounds including saponins and flavonol glycosides from tomato seeds and evaluated their effects on epidermal hydration. Among the isolated compounds, tomato seed saponins (10 µM) significantly increased the mRNA expression of proteins related to epidermal hydration, including filaggrin, involucrin, and enzymes for ceramide synthesis, by 1.32- to 1.91-fold compared with the control in HaCaT cells. Tomato seed saponins (10 µM) also decreased transepidermal water loss by 7 to 13 g/m²·h in the reconstructed human epidermal keratinization (RHEK) models. Quantitative analysis of the ceramide content in the stratum corneum (SC) revealed that lycoperoside H (1–10 µM) is a promising candidate to stimulate ceramide synthesis via the upregulation of ceramide synthase-3, glucosylceramide synthase, and β-glucocerebrosidase, which led to an increase in the total SC ceramides (approximately 1.5-fold) in concert with ceramide (NP) (approximately 2-fold) in the RHEK models. Evaluation of the anti-inflammatory and anti-allergic effects of lycoperoside H demonstrated that lycoperoside H is suggested to act as a partial agonist of the glucocorticoid receptor and exhibits anti-inflammatory effects (10 mg/kg in animal test). These findings indicate that lycoperoside H can improve epidermal dehydration and suppress inflammation by increasing SC ceramide and steroidal anti-inflammatory activity.     

Ruthenium(III) polyaminocarboxylate complexes: efficient and effective nitric oxide scavengers

The preparation of two Ru(III) polyaminocarboxylate complexes, AMD6245 and AMD6221, and their nitrosyl analogues, AMD6204, AMD6263, and AMD3689, is described. The compounds are characterized by IR, ES-MS, and (13)C and (15)N NMR spectroscopy where appropriate and cyclic voltammetry. The crystal structures for AMD6245, AMD6263, and AMD3689 are presented. AMD6245 (C(10)H(14)N(2)O(9)Ru) crystallized in the P2(1)/c space group with a = 8.4382(2) A, b = 8.8304(2) A, c = 17.6321(4) A, beta = 99.603(o), V = 1295.3(2) A(3), and Z = 4. AMD6263 (C(10)H(14)N(3)O(10)Ru) crystallized in the P2(1)/c space group with a = 9.9043(4) A, b = 13.1144(3) A, c = 12.0914(4) A, beta = 100.191(o), V = 1545.8(5) A(3), and Z = 4. AMD3689 (C(14)H(24.56)N(4)O(13.28)Ru) crystallized in the P1 space group with a = 8.838(2) A, b = 9.452(3) A, c = 13.419(4) A, alpha = 78.413(6)(o), beta = 75.804(6)(o), gamma = 73.562(6)(o), V = 1031.8(5) A(3), and Z = 2. The reaction of AMD6245 and AMD6221 with nitric oxide is investigated using EPR spectroscopy and stopped flow kinetics. Upon reaction with NO, a linear, diamagnetic [RuNO](6) complex is formed. The substitution reaction of AMD6245 with NO proceeds with a second-order rate constant of 2.24 x 10(7) M(-1) s(-1) at 7.3 degrees C (pH = 7.4; 50 mM phosphate buffer). The substitution reaction of AMD6221 with NO proceeds with a second-order rate constant of 3 x 10(5) M(-1) s(-1) at 20 degrees C (pH = 7.4; 50 mM phosphate buffered saline). The NO scavenging ability was assessed using a RAW264 murine macrophage assay by measuring the difference in nitrite produced between untreated control cells and treated cells. At 100 microM AMD6245 has [NO(2-)] = 12.5 microM less than the untreated cells and AMD6221 has [NO(2-)] = 37.6 microM less than the untreated cells. There is an insignificant difference in the amount of nitrite produced between AMD6263 or AMD3689 treated cells and untreated cells.     

Electrospray ionization mass spectrometry of tribenzyltin substituted-phenoxyacetate compounds

Hydrolysis products of organotin compounds RC(6)H(4)OCH(2)COOSn(CH(2)ph)(3) (R = o-NO(2), 1; m-NO(2), 2; p-NO(2), 3; o-CH(3), 4; o-OCH(3), 5; o-Cl, 6; o-Br, 7) and RC(6)H(3)OCH(2)COOSn(CH(2)ph)(3) (R = o,o-2CH(3), 8, o-OCH(3), p-CHO, 9; o,p-2Cl, 10), produced in aqueous acetonitrile solution, have been investigated by electrospray mass spectrometry (MS) and MS(n) techniques. The complexes [Y(2)SnXR'](-), [Y(3)SnXR'](-), [Y(3)SnX(2)R'](-), [Y(2)SnX(3)R'](-), and fragment ions of [Y(3)SnR'](-), plus abundant RC(6)H(4)(or RC(6)H(3))OCH(2)COO(-) and RC(6)H(4)(or RC(6)H(3))O(-) ions are observed in negative mode, whereas the protonated molecular ion [M + H](+), complexes [Y(2)SnXR'](+), [Y(3)SnXR'](+), [Y(2)SnX(2)R'](+), [Y(3)SnX(2)R'](+), [Y(2)SnX(3)R'](+), [Y(3)SnX(3)R'](+), as well as [YSnXR'](+), [M - CH(2)ph](+), XSn(+), (phCH(2))(3)Sn(+), phCH(2)Sn(+) (Y = &bond;CH(2)ph, X = &bond;OOCCH(2)OC(6)H(4)R(or C(6)H(3)R)) are detected in the positive mode. Water adduct ions are seen in both modes. The assignments are facilitated by agreement between observed and calculated isotopic patterns and tandem mass spectrometry studies.     

The effect of acidification on the determination of organic carbon, total nitrogen and their stable isotopic composition in algae and marine sediment

We investigated the effects of sample acidification on the stable carbon and nitrogen isotopic composition (delta13C and delta15N), as well as the organic carbon (OC) and total nitrogen (TN) composition, of an algal culture and a marine sediment. Replicate measurements of untreated and acid-treated samples were made using 1 M, 2 M and 6 M HCl, 6% H2SO3 and 1 M H3PO4. For all treatments the precision of the analysis for the acid-treated sample was equal to or less than that in the non-acidified sample. For the algae, analysis of variance (ANOVA) indicated no significant differences in the mean OC and TN concentration, or delta13C and delta15N composition, between any acid treatment and non-acidified samples. For the sediment sample a comparison could only be made between the different acid treatments because the untreated contained significant amounts ( approximately 30%) of carbonate carbon. ANOVA indicated that the mean OC determined in sediment samples after the 1 M HCl treatment and the mean delta13C values after the 6% H2SO3 and 1 M H3PO4 treatments were significantly different (p < 0.013 and < .05, respectively) from all other treatments. Mass balance calculations indicate that in some instances delta13C values were biased due to a contribution from unreacted carbonate carbon. There were no significant differences in the mean TN between any acid-treated and non-acidified samples. The mean delta15N values after 6 M HCl, 6% H2SO3 and 1 M H3PO4 treatments were significantly different from the untreated sediment sample (p < 0.044). Based on the significant bias observed for the delta15N and delta13C values, a weak (1-2 M) HCl solution is confirmed as the most appropriate acid for the removal of inorganic carbon from natural materials requiring elemental and isotopic analysis.     

Nanostructured Ag surface fabricated by femtosecond laser for surface-enhanced Raman scattering

Femtosecond laser was employed to fabricate nanostructured Ag surface for surface-enhanced Raman scattering (SERS) application. The prepared nanostructured Ag surface was characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The FESEM images demonstrate the formation of nanostructure-covered femtosecond laser-induced periodic surface structure, also termed as ripples, on the Ag surface. The AFM images indicate that the surface roughness of the produced nanostructured Ag substrate is larger than the untreated Ag substrate. The XRD and XPS of the nanostructured Ag surface fabricated by femtosecond laser show a face centered cubic phase of metallic Ag and no impurities of Ag oxide species. The application of the produced nanostructured Ag surface in SERS was investigated by using rhodamine 6G (R6G) as a reference chemical. The SERS intensity of R6G in aqueous solution at the prepared nanostructured Ag surface is 15 times greater than that of an untreated Ag substrate. The Raman intensities vary linearly with the concentrations of R6G in the range of 10(-8)-10(-4)M. The present methodology demonstrates that the nanostructured Ag surface fabricated by femtosecond laser is potential for qualification and quantification of low concentration molecules.     

The Analysis of Cell Contents of Some Papaveraceous Plants by Newly Devised Automated Histochemical Chromatography

Abstract

Contents of the colored cells (alkaloidal cells¹) found in Macleaya cordata root and Sanguinaria canadensis rhizome were analysed quantitatively by histochemical chromatography (HC) with the help of newly modified automated micromanipulator.

These were found to have 4 alkaloids viz protopine type protopine(1) and allocryptopine(2) and benzo- [c]phenanthridine type (sanguinarine(3) and cheleryth-rine(4)) in both the plants. Quantitatively the pro-topine alkaloids were 10-40 ng per cell while the benzo-[c]phenanthridines (as chlorides) were only 1-6 ng per cell in M. cordata root. However, in S. canadensis rhizome the relative quantities of the 4 alkaloids (1), (2), (3) and (4) were found to be 10, 13, 137 and 68 ng per cell respectively.     

Trace measurements of colchicine by adsorptive stripping voltammetry

A highly sensitive voltammetric method for trace measurements of the alkaloid colchicine is described. The method is based on the controlled adsorptive accumulation of the drug at the hanging mercury drop electrode, followed by voltammetric determination of the surface species. The adsorptive stripping response is evaluated with respect to preconcentration time and potential, solution pH, voltammetric waveform and other variables. With a 10-min preconcentration, a detection limit of 1.3 x 10(-10)M is obtained. The relative standard deviation (at the 1 x 10(-7)M level) is 1.1%. Applicability to urine analysis is illustrated.     

Simple and rapid extraction, separation, and detection of alkaloids in beverages

Implementation of an uncomplicated SPE process for the rapid extraction and preconcentration of the alkaloids, colchicine, strychnine, aconitine, and nicotine, from water, apple juice, and nonfat milk samples is presented. When coupled to analysis via micellar EKC (MEKC), the total analysis time per sample was less than 15 min for the water and juice samples and less than 20 min for the milk. The SPE process allowed for anywhere from a three to a fourteen-fold improvement in the LOD for each alkaloid when compared to detecting the alkaloids in a nontreated water sample matrix. Following SPE, the LODs for colchicine, strychnine, and nicotine were sufficient to meet levels from 150 to 5000 times more dilute than the LD(50) for a 50 kg individual drinking 12 oz of a contaminated beverage. Aconitine, on the other hand, was detected at approximately the LD(50) level. The percent recoveries for the SPE ranged from 37% to as high as 99%. Nicotine attained the highest recovery efficiencies, followed by colchicine, and finally, aconitine and strychnine, which were nearly identical. The greatest recovery efficiencies were achieved from apple juice and water, whereas nonfat milk yielded the lowest.     

Capillary electrophoretic study of the synergistic biological effects of alkaloids from Chelidonium majus L. in normal and cancer cells

In this study, the synergistic biological action of five celandine alkaloids in normal and cancer cells was investigated by capillary electrophoresis with light-emitting diode-induced native fluorescence detection. The specific capacity of each alkaloid to penetrate into the cells was estimated by monitoring alkaloid concentration decreases in the cell medium during incubation with murine fibroblast NIH/3T3, mouse melanoma B16F10, and human breast cancer MCF7 cell lines. Mixtures of isoquinoline alkaloids containing protopine, chelidonine, sanguinarine, allocryptopine, and stylopine were applied to cell cultures for 20 and 40 min, and the content of alkaloids in the cell media was measured by capillary electrophoresis (CE). CE separation of isoquinoline alkaloids was performed in 30 mM phosphate buffer (pH 2.5). As these alkaloids have native fluorescence, they were directly detected using the commercially available UV light-emitting diode without troublesome fluorescent derivatization. The results showed a differential ability of celandine alkaloids to penetrate into the normal and cancer cell interior, which was inversely proportional to their cytotoxic activity. While the most effective transport of celandine alkaloids from the cell medium to the cell interior was observed for normal murine fibroblast NIH/3T3 cells (about 55% of total content), cytotoxicity tests demonstrated selective and profound apoptotic effects of a five-alkaloid combination in the mouse melanoma B16F10 cell line.