Study on UPLC fingerprint and multi-component content determination of Microctis Folium from different origins / 国际中医中药杂志

Objective:To establish the fingerprints of Microctis Folium by ultra high performance liquid chromatography (UPLC); To determine the contents of three flavonoids in the Microctis Folium; To evaluate the quality difference of Microctis Folium from different producing areas. Methods:The fingerprints were performed on Agilent ZORBAX SB C18 column (2.1 mm×150 mm,1.8 μm). The mobile phase was acetonitrile - 0.1 % acetic acid solution with gradient elution at a flow rate of 0.30 ml/min. The column temperature was 30 ℃ and the detection wavelength was 315 nm. The common fingerprint peaks were identified by UPLC-mass spectrometry, and the identification results were confirmed by comparison of reference materials. Waters Cortecs T3 C18 chromatographic column (2.1 mm × 100 mm,1.6 μm) was used for content determination. The mobile phase was methanol-0.1 % formic acid solution with gradient elution at a flow rate of 0.35 ml/min. The column temperature was 30 ℃ and the detection wavelength was 339 nm. The contents of vitexin, isovitexin and narcissoside in 15 batches of Microctis Folium from different habitats were determine. Results:There were 11 common peaks in the fingerprint of Microctis Folium. Identified by mass spectrometry and confirmed by reference substance,10 chemical components were identified, including caffeic acid, p-hydroxycinnamic acid, ferulic acid, vitexin, isovitexin, kaempferol-3-O-rutoside, astragaloside, narcissoside, isorhamnetin-3-O-glucoside and linden glycoside. The similarity between the fingerprints of 15 batches of Microctis Folium and the control fingerprint was greater than 0.95, indicating that the overall similarity of the fingerprints of Microctis Folium from different producing areas was high. The total contents of three active components were 3.23-5.64 mg/g in Yangjiang City, Guangdong, 3.60-5.78 mg/g in Zhanjiang City, Guangdong, 4.68-5.73 mg/g in Yulin City, Guangxi and 3.87-5.21 mg/g in Wuzhishan City, Hainan . There was no significant difference in the content of three active components in different producing areas. Conclusion:The fingerprints and the determination method established in the study are stable and feasible, which can be used for the quality evaluation of Microctis Folium.

Bioactivity-guided isolation of the antidiabetic principle in Pterocarpus Santalinoides leaf extract

Abstract Pterocarpus santalinoides is used in Nigerian ethnomedicine to treat diabetes mellitus. This study aimed to establish the antidiabetic property of the plant, and isolate and characterize its active principle. Dried and pulverized leaves (500 g) of P. santalinoides were extracted with 1.8 L of 80 % hydromethanol by cold maceration. The dried extract (10 g) was partitioned into n-hexane, ethyl acetate (EtOAc), n-butanol, and water. Antidiabetic activitiy-guided isolation by column chromatographic separation of the EtOAc soluble and purification of the sub-fractions by repeated preparative thin layer chromatography (pTLC) yielded a C-glycosyl flavonoid, identified as isovitexin. The chemical structure was elucidated based on high-resolution mass spectroscopy, 1D, and 2D nuclear magnetic resonance spectroscopic analyses. Alloxan-induced diabetic rat model was adopted for antidiabetic screening. The extract of P. santalinoides (100-200 mg/kg), fraction F4 (50 mg/kg), sub-fraction F4.3 (10 mg/kg), and the semi-purified compound F4.3.2 (5 mg/kg) significantly (p<0.05) reduced the fasting blood glucose of alloxan-induced diabetic rats, causing 48.4, 69.4, 57.7 and 64.5 % antidiabetic activity respectively, compared with > 68 % recorded in glibenclamide (2 mg/kg) control. These results reveal that isovitexin is the antidiabetic principle in P. santalinoides

Towards the cosmetic application of Passiflora coccinea (Aubl.): antioxidant activity and photo protective capacity of the methanolic and glycolic leaf extracts

The present study aimed at the evaluation of Passiflora coccinea (Aubl.) antioxidant and photo protective in vitro activities, looking forward to their application as antiaging or sunscreen agents in cosmetic formulations. Methanolic and glycolic leaf extracts were prepared by three methods: ultrasound assisted extraction (UAE, 30 min.), maceration at room temperature (72 h) and maceration at 30 ºC (72 h). The antioxidant activities of the extracts were measured by DPPH and ORAC-FL assays and they were incorporated into a cosmetic emulsion to have their sun protection factor (SPF) measured spectrophotometricaly. The antioxidant activity of the emulsions were measured by DPPH and ORAC as well. C-glycosyl-flavones were identified in the extracts by ESI-MS/MS, in comparision with standards. The UAE methanolic extract and the maceration at 30 ºC glycolic extract were submmited to HPLC-DAD analysis and isovitexin was quantifyed in both by a validated method. The methanolic extract antioxidant activity was independent of the extraction method, higher than reported for other species of Passiflora and detectable when incorporated into the emulsion formulation. Maceration at 30oC was the most suitable method for glycolic extraction and its antioxidant activity was lower than the value presented by the methanolic extracts. None of the extracts exhibited a SPF value. Isovitexin in the UAE methanolic extract was 12.67 times higher than the most active glycolic extract, aside of their similar chromatographic profiles. Although a SPF value was not detected, the results indicate that P. coccinea can be a potential new source of antioxidants for topical antiaging formulations.

Simultaneous determination of eight components before and after processing of Gentiana crassicaulis by UPLC-Q-Orbitrap HRMS / 中草药

Objective: To develop and validate a ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap HRMS) Methods: for simultaneously qualitative and quantitative determination of eight chemical components (gentiopicroside, loganic acid, swertiamarin, sweroside, luteolin, isovitexin, apigenin, and kaempferol) in raw and processed products of Gentiana crassicaulis. Methods Waters Acquity UPLC BEH C18 (100 mm × 2.1 mm, 1.7 μm) column was used for gradient elution with methanol-0.1% formic acid in mobile phase. The volume flow was 0.3 mL/min and the column temperature was 35 ℃. The mass spectrometer was detected using negative ion detection mode. Results: After frying and wine frying, the content of iridoid in G. crassicaulis was significantly increased. Statistically, the differences between gentiopicroside and loganic acid after frying were significant. The content of flavonoids changed little after frying and wine frying. The total content changes of the two components were as follows: the content of iridoids: frying > wine frying > raw products; flavonoids content: raw products > wine frying > frying. Conclusion: Based on UPLC-Q-Orbitrap HRMS, the quantitative analysis method of eight components of raw and processed products of G. crassicaulis was established, which provided a basis for optimizing the processing technology of G. crassicaulis and improving the clinical curative effect of G. crassicaulis.

Qualitative and Quantitative Study of Tibetan Medicine Thlaspi semen / 中国药房

OBJECTIVE： To establish the qualitative and quantitative control method of Tibetan medicine Thlaspi semen. METHODS： TLC and HPLC method were used to identify and determine flavonoids isovitexin， swertisin and glucosinolates sinigrin from 15 batches of T. semen. The stationary phases identified by TLC of flavonoids and glucosinolates were polyamide film and high performance silica gel GF254. The developing agents were trichloromethane-methanol-glacial acetic acid （11 ∶ 1 ∶ 1，V/V/V） and ethyl acetate-methanol- triethylamine （4 ∶ 5 ∶ 0.5，V/V/V）. In chromatogram condition of content determination of isovitexin and swertisin， the separation was performed on CAPCELL PAK MGⅡ C18 column with mobile phase composed of acetonitrile-0.4％ glacial acetic acid solution （gradient elution） at the flow rate of 1.0 mL/min. The detection wavelength was set at 336 nm. In chromatogram condition of content determination of sinigrin， the separation was performed on CAPCELL PAK MGⅡ C18 column with mobile phase composed of acetonitrile-0.02 mol/L tetrabutylammonium hydrogen sulfate （15 ∶ 85，V/V，pH 6） at the flow rate of 1.0 mL/min. The detection wavelength was set at 227 nm. RESULTS： In TLC identification chromatogram， spots corresponding to isovitexin， swertisin and sinigrin control were detected in test samples. The linear ranges of isovitexin， swertisin and sinigrin were 1.26-79.00， 1.21-75.38， 12.80-640.00 μg/mL， respectively （all r≥0.999 5）. The limits of detection （LODs） were 0.09， 0.12， 0.15 μg/mL， and limits of quantitation （LOQs） were 0.39， 0.43， 0.54 μg/mL， respectively. RSDs of precision， stability （24 h） and reproducibility tests were all lower than 2.0％（n＝6）. The recoveries were 99.1％， 97.0％ and 98.1％， and RSDs were 1.9％， 1.8％， 1.8％（n＝6），respectively. The contents of isovitexin， swertisin and sinigrin in 15 batches of T. semen were 0.013-0.090， 0.020-0.130 and 18.92-40.75 mg/g， respectively. CONCLUSIONS： Established quality control method is simple， reproducible and stable， and can be used for the quality control of Tibetan medicine T. semen.

Study on HPLC specific chromatograms of effective parts and determination of five components of Filifolium sibiricum / 中草药

Objective: To establish the HPLC specific chromatograms of the ethyl acetate layer in ten batches of effective parts of Filifolium sibiricum and to determine the contents of five components. Methods: The analysis of effective parts of F. sibiricum was performed on a Thermo AcclaimTM120 C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (B)-PBS (A) (0.1 mol/L sodium dihydrogen phosphate-2% glacial acetic acid, 1∶1) as the mobile phase in a gradient elution mode, the detection wavelength was set at 360 nm, the flow rate was 0.8 mL/min, and the column temperature was 35 ℃. Results: The specific chromatograms of F. sibiricum effective parts were established and ten common peaks were designated. Among them, five components including isorientin, isovitexin, isoquercitrin, luteoloside and isorhamnetin-3-O-β-D-glucose all showed good linear relationship within the ranges of 0.018—0.108, 0.066 8—0.400 8, 0.088—0.528, 0.118 4—0.710 4 and 0.017 6—0.105 6 μg, respectively. The average recovery was 98.67%, 97.93%, 98.95%, 99.81%, and 97.33% with the RSD value at 1.10%, 0.93%, 1.10%, 0.62%, and 1.48%, respectively. Moreover, the similarity of the eight batches of samples was above 0.9 in the ten batches of medicinal herbs, the similarity of the two batches of which was 0.688 and 0.695, indicating that its content was lower and the difference was greater. In addition, there were significant differences in the content of five components in each harvest time. The content of flavonoids in medicinal herbs was higher with high flower percentage. It was suggested that the content of flavonoids in F. sibiricum was related to the flower percentage of harvest period. Conclusion: The HPLC specific chromatograms of the F. sibiricum effective parts were established and the common characteristic peaks were determined, which could be used for quality control of the F. sibiricum.

Chemical constituents of Gendarussa vulgaris / 中草药

Objective To study the chemical constituents of Gendarussa vulgaris. Methods The chemical constituents were isolated and purified with silica column chromatography and gel chromatography, etc. Their structures were identified by physico- chemical properties and various spectroscopic methods including NMR spectrum, MS, UV, etc. Results A total of 16 compounds were isolated and elucidated as daucosterol (1), 6″-O-acetylisavitexin (2), 9,10-dihydroxy-4,7-megastigmadien-3-one (3), 22E,24R-ergosta- 7,22-diene-3β,5α,6β,9α-tetraol (4), isorhamnetin (5), quercetin (6), eleutheroside E (7), gusanlung A (8), gusanlung B (9), betulin (10), isovitexin-2″-O-rhamnoside (11), isovitexin (12), genkwanin (13), apigenin (14), quercetin 3-O-β-D-glucuronide (15), and 2-(4-hydroxy-3-methoxyphenyl)-3-(2-hydroxy-5-methoxyphe-nyl)-3-oxo-1-propanol (16). Conclusion Compounds 3, 5, 11, 12 and 15 are isolated from G. vulgaris for the first time. Compound 2, 4, 13, and 16 are isolated from the plant of genus for the first time.

Isovitexin as marker and bioactive compound in the antinociceptive activity of the Brazilian crude drug extracts of Echinodorus scaber and E. grandiflorus

Abstract Echinodorus scaber Rataj and Echinodorus grandiflorus (Cham. & Schltdl.) Micheli, Alismataceae, are popularly used to relieve inflammatory complaints and as diuretic. A study on the antinociceptive effect and selected marker compounds in eleven extracts from different locations was undertaken and their antinociceptive effect was assessed. The fingerprints were compared by HPLC-DAD and the content of vitexin, isovitexin, isoorientin and vitexin-2-O-rhamnoside were determined. All samples presented antinociceptive activity reducing the writhes by 36.4-62.5% and 47.4-79.8% at 10 and 50 mg/kg, respectively; indomethacin (5 mg/kg) reduced writhes by 82.6-90.1%. The content of the flavonoids C-glycosides, however, presented a strong variation. Isovitexin and isoorientin were found in all the samples, with content ranging from traces to 14.70 µg/mg and 2.12-84.27 µg/mg extract, respectively, while vitexin-2-O-rhamnoside occurred in quantifiable amounts only in 3 out of 11 samples ranging from 5.43 to 33.13 µg/mg extract; vitexin was not detected at all or detected in trace amounts. According to the fingerprints, the samples could be arranged in four main groups. All eleven extracts showed antinociceptive activity. Isovitexin was the only flavonoid present in all samples and can be regarded, acting in synergy with the other compounds or not, as the responsible for the antinociceptive activity. Therefore, isovitexin is a good choice as chemical marker when the antinociceptive activity of E. scaber and E. grandiflorus is investigated.

Rapid identification and quantitative analysis of chemical constituents of Gentiana veitchiorum by UHPLC-PDA-QTOF-MS

ABSTRACT Gentiana veitchiorum Hemsl., Gentianaceae, a traditional Tibetan medicine, was used for the treatment of liver jaundice with damp-heat pathogen, as well as for headache and chronic pharyngitis. A rapid ultra-performance liquid chromatography, photodiode array detector, quadrupole time-of-flight mass spectrometry method was developed for the fast and accurate identification and quantification of the chemical constituents of G. veitchiorum. In fact, eighteen compounds were detected and identified on the basis of their mass spectra, fragment characteristics and comparison with published data. Especially, the MS fragmentation pathways of iridoid glycosides and flavone C-glycosides were illustrated. Five compounds among them were quantified by UHPLC-PDA, including swertiamarin, gentiopicroside, sweroside, isoorientin, and isovitexin. The proposed method was then validated based on the analyses of linearity, accuracy, precision, and recovery. The overall recoveries for the five analytes ranged from 96.54% to 100.81%, with RSD from 1.05% to 1.82%. In addition, ten batches of G. veitchiorum from different areas were also analyzed. The developed method was rapid and reliable for both identification and quantification of the chemical constituents of G. veitchiorum, especially for simultaneous qualitative and quantitative analysis of iridoid glycosides and flavone C-glycosides.

Effects of isovitexin on transient outward potassium current of ventricular myocytes in rats / 中国中药杂志

To investigate the effects of isovitexin Ⅳ on transient outward potassium current in rat ventricular myocytes. In this study, MTT assay was used to investigate the safe range of isovitexin. The results showed that the IC₅₀ of the drug was in the range of 10-30 μmol•L⁻¹, and the drug concentration of 1-3 μmol•L⁻¹ for the patch clamp test was within the safe range. In addition, the single ventricular myocytes were obtained by single-enzymatic hydrolysis through aortic retrograde perfusion. The transient outward potassium current (Ito) of rat ventricular myocytes was guided and measured by whole-cell patch-clamp technique and the changes of current characteristics were recorded after isovite was applied. When the concentration of IV was less than 0.1 μmol•L⁻¹, there was no significant effect on Ito. However, with the increase in the concentration of IV (≥0.3 μmol•L⁻¹), the peak of Ito was decreased gradually, from (32.32±2.9) pA/pF to （25.83±4.3） pA/pF, 1 μmol•L⁻¹ IV and (19.51±3.5) pA/pF, 3 μmol•L⁻¹ IV respectively, with an inhibition effect in a concentration-dependent manner. In the range of 1-3 μmol•L⁻¹, IV down-regulated the I-V curve of Ito significantly. The activation curve showed that IV can enable the maximum half activation potential (V1/2) to move to the positive direction, and the V1/2 was increased from (19.59±1.6) mV to (22.81±1.7) mV and (28.86±1.4) mV at concentration of 1, 3 μmol•L⁻¹, meanwhile the activation curve moved to the right. However, the maximum half inactivating potential (V1/2) of the steady-state inactivation curve of Ito was significantly decreased from (－51.43±0.99) mV to (－61.81±1.3) mV with concentration of 1 μmol•L⁻¹ and (－71.50±1.4) mV with concentration of 3 μmol•L⁻¹. The inactivation time constant of recovery from inactivation (τ) was up-regulated significantly from (94.89±0.73) ms to (118.5±1.5) ms and (162.4±1.4) ms at concentration of 1, 3 μmol•L⁻¹ respectively. Meanwhile IV could enable the inactivation recovery curve to move to the right, which suggested that it can prolong the recovery time from inactivation of the transient outward potassium channel. In conclusion, isovitexin had a high inhibitory effect on Ito in rat ventricular myocytes.

Chemical Constituents from Stem Barks of Pandanus tectorius / 中国药学杂志

OBJECTIVE: To study the chemical constituents in the stem barks of Pandanus tectorius Soland. METHODS: The compounds were isolated by repeated chromatography. Their structures were elucidated by spectroscopic methods. RESULTS: Ten compounds were isolated and identified as 1'-O-benzyl-α-L-rhamnopyranosyl-(1″→6')-β-D-glucopyranoside(1), dihydrodehydrodiconiferyl alcohol(2), isovitexin(3), vitexin(4), 3,5-di-O-caffeoylquinic acid methyl ester(5), 3,5-di-O-caffeoylquinic acid ethyl ester(6), 3,4-di-O-caffeoylquinic acid methyl ester(7),(+)-lyoniresinol 3a-O-β-glucopyranoside(8),(-)-lyoniresinol 3a-O-β-glucopyranoside(9), and benzyl-β-D-glucopyranoside(10). CONCLUSION: All compounds are isolated from this plant for the first time.

Simultaneous Determination of Four Glycosides in Microctis Folium by UPLC / 中国药师

Objective:To develop a UPLC method for determining four glycosides in microctis folium.Methods:The UPLC deter-mination was performed on an Agilent SB -C18 (3.0 mm ×50 mm, 1.8 μm) colume with 0.05% acetonitrile -phosphate solution as the mobile phase.The detection wavelength was set at 320 nm.The flow rate was 0.3 ml· min-1.The column temperature was 25℃.Results:Narcissoside, isovitexin, kaempferol-3-rutinoside and isorhamnetin-3-O-glucoside all showed good linearity with the re-covery of 98.89%,99.03%, 97.00%and 97.41%, and RSD of 0.41%, 0.84%,0.44%and 0.80%, respectively (n=9).Con-clusion:The method is convenient with good stability , repeatability and sample recovery rate , which provides basis for the quality eval-uation and control of microctis folium.

Contents of seven indicative constituents in seven kinds of Gentiana macrophylla by UPLC / 中草药

Objective: An ultra performance liquid chromatographic (UPLC) method was developed for simultaneously determining seven constituents, such as loganic acid, swertiamarin, 6'-O-β-D-glucosyl gentiopicroside, gentiopicroside, sweroside, isoorientin, and isovitexin, from the medicinal plants of Gentiana macrophylla. Methods: The separation was performed on an Acquity UPLC® BEH C18 column (50 mm ×2.1 mm, 1.7 μm) through a gradient elution of methanol-0.04% aqueous phosphorite at a flow rate of 0.3 mL/min. The detection wavelength was 242 nm, and the column temperature was set at 30℃. Results: For the seven analytes, loganic acid, swertiamarin, 6'-O-β-D-glucosyl gentiopicroside, gentiopicroside, sweroside, isoorientin, and sovitexin, a good linearity (r≥0.9995) was obtained in the range of 2.100-537.100, 1.050-270.000, 0.920-236.000, 11.100-2830.000, 0.750-192.000, 0.167-102.000, and 0.216-52.800 μg, respectively. Their average recoveries (n=6) were 97.83%-100.08%, respevtively, with RSD values less than or equal to 3.76%. Conclusion: The UPLC method is simpler and more effective than HPLC, and can be used for the simultaneous determination of seven indicative constituents in medicinal plants of G. macrophylla.

Determination of seven components in flowers of Gentiana tibetica and Gentiana dendrologi by HPLC / 中草药

Objective: To establish an HPLC method for simultaneously determining seven components, such as loganic acid, 6′-O-β-D-glucopyranosyl gentiopicroside, swertiamarine, gentiopicroside, swertiamarin, isoorientin, and isovitexin, from the flowers of Gentiana tibetica and G. dendrology. Methods: Chromatographic analysis was achieved on an Agilent Zorbax ODS column (150 mm × 4.6 mm, 5 μm) by gradient elution of acetonitrile-0.4% acetic acid in water at 30℃. The flow rate was 0.4 mL/min and the detection wavelength was 254 nm. Results: The calibration curves of all the seven constituents showed good linearity in a relatively wide concentration range. The linear ranges of loganic acid, 6′-O-β-D-glucopyranosyl gentiopicroside, swertiamarine, gentiopicroside, gentiopicroside, isoorientin, and isovitexin were 0.228-2.280, 0.680-6.800, 0.220-2.20, 1.476-14.760, 0.200-2.000, 0.436-4.360, and 0.276-2.760 μg (R2 ≥ 0.999 2), respectively. The recoveries (n = 9) of loganic acid, 6′-O-β-D-glucopyranosyl gentiopicroside, swertiamarine, gentiopicroside, gentiopicroside, isoorientin, and isovitexin were 100.9%, 99.4%, 101.0%, 105.7%, 103.1%, 98.4%, 104.2%. Conclusion: This method is simple, accurate, and specific, and can be used for the determination of seven constituents in the flowers of G. tibetica and G. dendrologi.

A new flavonoid glycoside from leaves of Vitex negundo var. cannabifolia / 中草药

Objective: To investigate the flavonoid glycosides from the leaves of Vitex negundo var. cannabifolia. Methods: Column chromatography including silica gel, Sephadex LH-20, and ODS was used to separate and purify the chemical constituents, and their structures were elucidated by physicochemical properties, MS, and NMR spectroscopic data. Results: Seven flavonoid glycosides were obtained from the ethyl acetate layer of 95% EtOH extract of the leaves of V. negundo var. cannabifolia, and identified as luteolin-4'-O-(6″-O-p-hydroxybenzoyl)-β-D-glucoside (1), luteolin-7-O-(6″-O-p-hydroxybenzoyl)-β-D-glucoside (2), luteolin-6-C-(6″-O-trans-caffeoyl)-β-D-glucoside (3), luteolin-6-C-(2″-O-trans-caffeoyl)-β-D-glucoside (4), perfoliatumin A (5), isovitexin (6), and luteolin-7-O-β-D-glucoside (7). Conclusion: Compound 1 is a new compound named cannabifolin G; Compounds 2-4 and 7 are obtained from this plant for the first time; Compound 5 is firstly isolated from the plants in Vitex L.

Chemical constituents from flower of Gentiana tibetica / 中草药

Objective: To investigate the chemical constituents in flowers of Gentiana tibetica. Methods: The chemical constituents were isolated from the 95% alcohol extract of G. tibetica flowers by silica column chromatography, Sephadex LH-20, C18 and RP-HPLC. Their chemical structures were elucidated on the basis of IR, ESI-MS, 1H-MNR, and 13C-MNR spectroscopic data. Results: Twelve compounds, including chromene, flavones C-glycosides, secoiridoid glycosides, iridoid glycosides, aliphatic alcohol, and disaccharide, were obtained from the 95% alcohol extract of G. tibetica flowers, Their structures were identified as macrophylloside D (1), orientin 7-caffeate (2), 7-O-feruloylorientin (3), isovitexin (4), saponarin (5), isoorientin (6), 6'-O-β-D-glucopyranosyl gentiopicroside (7), sweroside (8), swertiamarine (9), loganic acid (10), 1-heneicosanol (11), and sucrose (12). Conclusion: Compounds 1-12 are isolated from G. tibetica for the first time.

HPLC Simultaneous Determination of Vitexin and Isovitexin inMelastoma Dodecandrum / 世界科学技术-中医药现代化

This study was aimed to develop HPLC for determination of vitexin and isovitexin inM. dodecandrum. The HPLC column was SunFireTM C18 (4.6 mm× 150 mm, 5μm). The detection wavelength was 365 nm. The mobile phase was methanol-0.2% formic acid aqueous solution. The column temperature was 40℃. The flow rate was 1.0 mL·min-1. The results showed that the regression equations of vitexin and isovitexin wereY = 1× 106X– 14 396, Y = 1× 106X– 13 900, respectively. The linear ranges were 0.210μg - 1.050μg (r = 0.999) and 0.186μg - 0.930μg (r = 1.000), respectively. The recovery rates were 97.48% and 104.64%, respectively. The RSD were 2.32%and 1.51%, respectively. The sample contents of vitexin and isovitexin were 1.25 and 1.86 mg·g1, respectively. It was concluded that the method was simple, feasible and reproducible for the content determination of vitexin and isovitexin inM. dodecandrum.

Seasonal variations in the amount of isoorientin and isovitexin in Cecropia glaziovii Sneth. leaves over a two-year period / Variación estacionaria en el contenido de isoorientina e isovitexina en hojas de Cecropia glaziovii Sneth. durante un período de dos años

Cecropia glaziovii Sneth. (Urticaceae) is a common tree from Southeast and South of Brazil, being widely used in traditional medicine to treat heart and respiratory conditions. C-glycosylflavonoids have being described as the major compounds for this genus, however, no seasonality studies of individual flavonoids was conducted for any Cecropia specie. In this work, the content of isoorientin and isovitexin in aqueous extract from the leaves of C glaziovii during a two-year period was determined by high-performance liquid chromatography with diode array detector (HPLC-DAD). Seasonal alterations in the content of these two majority C-glycosylflavonoids as well its possible correlation with the pluviosity in the period of January/2008 to January/2010 were determined. Isoorientin presented higher content in November/09 (6.04 mg/g of extract) and lower content in May/08 (1.01 mg/g of extract). The higher content of isovitexin was observed in March/09 and the lower in September/08 (11.42 and 4.47 mg/g of extract, respectively). Although they have distinct behaviors, it was not observed correlation between the values of pluviosity and the production of these C-glycosylflavonoids.

Cecropia glaziovii Sneth. (Urticaceae) es un árbol comúnmente encontrada en el Suroriente y Sur de Brasil, siendo ampliamente utilizada en la medicina tradicional para el tratamiento de problemas cardíacos y respiratorios. Flavonoides C-glucósidos vienen siendo descritos como los compuestos mayoritarios del género, sin embargo, ningún estudio de estacionalidad de flavonoides analizados de modo individual fue realizado con ninguna especie de Cecropia. En el presente trabajo, el contenido de isoorientina e isovitexina en el extracto acuoso de las hojas de C. glaziovii durante un período de dos años fue determinado por HPLC-DAD. Variaciones estacionarias en el contenido de esos dos flavonoides C-glucósidos así como la posible correlación con la pluviosidad en el periodo de Enero/2008 hasta Enero/2010 fueron determinados. Isoorientina presentó mayor contenido en Noviembre/09 (6,04 mg/g de extracto) y menos contenido en Mayo/08 (1,01 mg/g de extracto). El mayor contenido de isovitexina fue observado in Marzo/09 y el menor contenido in Septiembre/08 (11,42 y 4,47 mg/g de extracto, respectivamente). Aunque los flavonoides poseen distintos comportamientos, no fue observada correlación entre los valores de pluviosidad y la producción de esos compuestos.

Chemical constituents of whole plant of Oxalis pes-caprae L / 中国药学杂志

OBJECTIVE: To study the chemical constituents of Oxalis pes-caprae L. METHODS: The chemical constituents were isolated and purified with silica column chromatography and gel chromatography, etc. Their structures were identified by physicochemical properties and various spectroscopic methods including NMR spectrum, MS, UV, etc. RESUTLS: Twelve compounds were isolated from the ethyl acetate part, among which 10 compounds were elucidated as daucosterol(1), β-sitosterol(2), vitexin(3), isovitexin(4), acacetin(5), robinin(6), β-tocopherol(7), tartaric acid(8), vanillic acid(9), and luteolin(10). CONCLUSION: All compounds are isolated from Oxalis pes-caprae L. for the first time.

Flavonoid compounds of whole plant of Crotalaria sessiliflora L / 中国药学杂志

OBJECTIVE: To investigate the flavonoid constituents of Crotalaria sessiliflora L.