Anti-inflammatory and gastroprotective properties of Hypericum richeri oil extracts

Oil extracts of flowering tops of Hypericum richeri Vill. prepared in three different ways were evaluated for chemical composition, and anti-inflammatory and gastroprotective activities. An HPLC method was developed for determination of two dominant flavonoids, quercetin and I3,II8-biapigenin. The carrageenan-induced rat paw edema test was used for screening the anti-inflammatory activity, while indomethacin-induced rat gastric mucosa damage test was used for evaluation of gastroprotective activity. The oil extract prepared by maceration with 96% ethanol, followed by extraction with sunflower oil by heating on a water bath, exhibited the highest anti-inflammatory (38.4%) and gastroprotective activities (gastric damage score of 0.9). The same oil extract had the highest content of quercetin (49 microg/mL) and I3,II8-biapigenin (60 microg/mL). These results approve the usage of oil extracts of H. richeri as an anti-inflammatory and gastroprotective agent.

Quercetin aglycone is bioavailable in murine pancreas and pancreatic xenografts

Quercetin is a potential chemopreventive and chemotherapeutic agent for pancreatic and other cancers. This study examined the distribution of quercetin in plasma, lung, liver, pancreas, and pancreatic cancer xenografts in a murine in vivo model and the uptake of quercetin in pancreatic cancer MiaPaCa-2 cells in a cellular in vitro model. Mice were randomly allocated to control or 0.2 and 1% quercetin diet groups utilizing the AIN93G-based diet (n = 12 per group) for 6 weeks. In addition, 6 mice from each group were injected weekly with the chemotherapeutic drug gemcitabine (120 mg/kg mouse, ip). MiaPaCa cells were collected from culture medium after cells were exposed to 30 muM quercetin for 0.5, 1, 2, 4, 8, and 24 h. Levels of quercetin and 3-O'-methylquercetin in mouse tissues and MiaPaCa-2 cells were measured by high-pressure liquid chromatography following enzymatic hydrolysis and then extraction. The study showed that quercetin is accumulated in pancreatic cancer cells and is absorbed in the circulating system, tumors, and tissues of pancreas, liver, and lung in vivo. A higher proportion of total quercetin found in tumors and pancreas is aglycones. Gemcitabine cotreatment with quercetin reduced absorption of quercetin in the mouse circulatory system and liver. Results from the study provide important information on the interpretation of the chemotherapeutic efficacy of quercetin.

Simultaneous quantification of 14 bioactive constituents in Forsythia suspensa by liquid chromatography-electrospray ionisation-mass spectrometry

INTRODUCTION

Forsythia suspensa is a commonly used traditional Chinese medicine including phenylethanoid glycosides, lignans, flavonoids, terpenes and volatile oils. Quantification of multi-components is important for the quality control of Forsythia suspensa.

OBJECTIVE

To establish a liquid chromatography-electrospray ionisation-mass spectrometry method for simultaneous quantification of 14 bioactive constituents of Forsythia suspensa in different places of China and different parts of this herb.

METHODOLOGY

The optimal chromatographic conditions were achieved on a Kromasil C(18) column (150 yen 4.6 mm, 5 microm) with gradient elution of methanol, acetonitrile and 0.1% formic acid in 27 min. Detection was performed in negative ionisation mode by monitoring the precursor-product combination in multiple reaction monitoring (MRM) mode. The validation of the method included tests of linearity, sensitivity, precision, repeatability, stability and accuracy.

RESULTS

All calibration curves showed good linear regression (r > 0.9990) within test ranges. The established method showed good precision and accuracy with overall intra-day and inter-day variations of 0.7-4.3 and 1.1-3.9% respectively, and overall recoveries of 96.65-101.2% for the compounds analysed.

CONCLUSION

The proposed method was successfully applied for the quantitative analysis of 14 constituents in 12 Forsythia suspensa samples.

[Screening of anti-diarrhea effective fractions from guava leaf]

OBJECTIVE

To screen the fractions from guava leaf to ascertain the effective anti-diarrhea fraction and to establish the method of quality control.

METHODS

A series of samples from guava leaf were prepared through extraction and separation by solvents progressively, and their effect on the mice diarrhea models induced by senna decoction were tested individually; and the constituent correlated with the effect of the samples on the models was determined by HPLC.

RESULTS

The effect of the fractions with moderate-polar glucosides from guava leaf was better than that of the other fractions; the effect of the fractions with the glucosides was correlated with the content of the quercetin glucosides in the fractions.

CONCLUSION

The fractions with the moderate-polar glucosides is the effective anti-diarrhea fraction of guava leaf; determination of the quercetin glucosides can be used for quality control of guava leaf and its extracts.

Simultaneous detection of pro- and antioxidative effects in the variants of the deoxyribose degradation assay

Interest in the redox properties of natural products has led to the development of various assays for the detection of antioxidant activities and ROS-scavenging properties. Here, additional modifications of the 2-deoxy-d-ribose degradation assay are introduced that specifically allow the determination of interactions of the test compound with the autoxidation of ascorbic acid and the autoxidation of the test compound itself. To illustrate this, juglone and quercetin were used as examples. The modified assay systems provide insights into their specific antioxidative and pro-oxidative properties. In additional, an extensive characterization of the redox properties of their complex with iron is possible, if iron ions are added in the free form or complexed with EDTA. The juglone-iron complex proved to be pro-oxidative in a wider range of milieus than the quercetin-iron complex.

Quercetin and isorhamnetin in sweet and red cultivars of onion (Allium cepa L.) at harvest, after field curing, heat treatment, and storage

Effects of heat treatment and storage on quercetin and isorhamnetin content, major and minor components of isorhamnetin, and quercetin glucosides and aglycone, were investigated in onion (Allium cepa L.). The sweet onion 'Recorra' and red onions 'Hyred' and 'Red Baron' were cultivated in the south part of Norway and thereafter stored for eight months. The onions were either not field dried, but stored directly, or field dried and then stored, or field dried and then heat treated before storage. Neither storage nor heat treatment caused any major differences in total flavonol content in the investigated sweet onion as well as in the red onion cultivars. The two major quercetin glucosides differed in their changes in content during storage; quercetin-4'-glucoside did not show any consistent changes during storage in the two red cultivars, independent of treatment, whereas quercetin-3,4'-diglucoside increased significantly by 30 or 51%, respectively, during storage in 'Hyred' and 'Red Baron' in the 24 h heat treated onions. Isorhamnetin-4'-glucoside, which might possibly be of special interest from a human health point of view, was present at 2-3 times higher amount in the sweet onion cultivar than in the two red cultivars. Some of the quercetin glucosides present at lower concentrations, isorhamnetin-3,4'-diglucoside, quercetin-3,7,4'-triglucoside, and quercetin-7,4'-diglucoside, increased during storage in all treatments in both 'Hyred' and 'Red Baron', though sometimes a decrease was found at the end of storage.

[Studies on HPCE fingerprint of Folium Apocyni Veneti]

OBJECTIVE

To establish the analytical method for the fingerprint of Folium Apocyni Veneti by HPCE and estimate the quality of Folium Apocyni Veneti from different habitats.

METHODS

Folium Apocyni Veneti from different habitats were analyzed and the chromatographic fingerprint were determined by HPCE. The data were analysed by Fuzzy Cluster and Fingerprint Similarity Evaluation Software to compare the similarity of samples.

RESULTS

HPCE fingerprint of 7 main peaks was established preliminarily. It was discovered that a small number of samples differed from others.

CONCLUSION

The method is reliable, accurate and can be used for quality control of Folium Apocyni Veneti.

Substituted pyrazinecarboxamides as abiotic elicitors of flavolignan production in Silybum marianum (L.) gaertn cultures in vitro

Substituted pyrazinecarboxamides markedly influenced production of flavonolignans in Silybum marianum callus and suspension cultures. In this study the effect of two compounds, N-(3-iodo-4-methylphenyl)pyrazine-2-carboxamide (1) and N-(3-iodo-4-methylphenyl)-5-tert-butyl-pyrazine-2-carboxamide (2), as abiotic elicitors on flavono-lignan production in callus culture of S. marianum was investigated. Silymarin complex compounds have hepatoprotective, anticancer and also hypocholesterolemic activity. In vitro flavonolignan concentration in cells is very low and the elicitation is one of the methods to increase production. Elicitors were tested at three concentrations and at different culture times. In the case of elicitation with 1, the greatest increase of flavonolignan and taxifoline production was observed at concentration c(1a) after 6-hours of elicitation and after 24 and 72-hours at concentration c(1b). However, increased production of silychristin, one of the compounds in the silymarin complex, was achieved after only 6-hours elicitation with c(1a) (2.95 x 10(-4) mol/L). The content of silychristin was 2-times higher compared to the control sample. An increased production of silychristin was reached with compound 2 at the concentration c(2) (2.53 x 10(-3) mol/L) after 72 h of elicitation. The production of silychristin in this case was increased 12-times compared to control.

HPLC/MS analysis and anxiolytic-like effect of quercetin and kaempferol flavonoids from Tilia americana var. mexicana

AIM OF THE STUDY

Around the world, Tilia species have been used in traditional medicine for their properties as tranquilizer. Furthermore, Mexican species of Tilia have been grouped as Tilia americana var. mexicana, but their specific content in flavonoids is poorly described. In this study, inflorescences of Mexican Tilia were collected in three different regions of Mexico to compare their flavonoid content and anxiolytic-like response.

MATERIALS AND METHODS

Flavonoid content was analyzed by using an HPLC-MS technique. For anxiolytic-like response, Tilia inflorescences extracts (from 10 to 300 mg/kg, i.p.) were tested in experimental models (open-field, hole-board and plus-maze tests, as well as sodium pentobarbital-induced hypnosis) in mice.

RESULTS

HPLC-MS analysis revealed specific peaks of flavonoid composition demonstrating some differences in these compounds in flowers and bracts depending on the region of collection. No differences in the neuropharmacological activity among these samples of Tilia were found. Moreover, their effects were associated with quercetin and kaempferol glycosides.

CONCLUSIONS

Dissimilarities in the flavonoid composition of Mexican Tilias might imply that these species must be re-classified in more than one species, not as a unique Tilia americana var. mexicana. Since quercetin and kaempferol aglycons demonstrated anxiolytic-like response and that no difference in the pharmacological evaluation was observed between these three Mexican Tilias, we suggest that this pharmacological effect of Tilia inflorescences involves these flavonoids occurrence independently of the kind of glycosides present in the samples reinforcing their use in traditional medicine in several regions of Mexico.

[Study on fingerprints of the stems of Actinidia deliciosa by HPLC]

OBJECTIVE

To establish the fingerprint spectrum of the stems of Actinidia deliciosa by HPLC.

METHODS

HPLC fingerprint analysis of the stems of Actinidia deliciosa was developed and the thermo Hypersil BDS C18 column (250 mm x 4.6 mm, 5 microm) was used. The mobile phase consisted of Acetonitril-0.1% phosphoric acid with gradient elution. The column temperature was 20 degrees C, the detective wavelength was 296 nm, the flow rate was 1.0 mL/min, and the sample injection was 20 microL.

RESULTS

Fingerprint spectrum of the stems of Actinidia deliciosa was established, and 16 samples of different origin Actinidia deliciosa were detected. Twenty-eight peaks in chromatogram were common. There was a high similarity and each chromatographic peak was obtained with good separation correlation according to the technical requirements of fingerprint of Chinese traditional medicine.

CONCLUSION

This method is accurate, reliable and provides a scientific basis for controlling the quality of the stems of Actinidia deliciosa.

Matrix-free UV-laser desorption/ionization (LDI) mass spectrometric imaging at the single-cell level: distribution of secondary metabolites of Arabidopsis thaliana and Hypericum species

The present paper describes matrix-free laser desorption/ionisation mass spectrometric imaging (LDI-MSI) of highly localized UV-absorbing secondary metabolites in plant tissues at single-cell resolution. The scope and limitations of the method are discussed with regard to plants of the genus Hypericum. Naphthodianthrones such as hypericin and pseudohypericin are traceable in dark glands on Hypericum leaves, placenta, stamens and styli; biflavonoids are also traceable in the pollen of this important phytomedical plant. The highest spatial resolution achieved, 10 microm, was much higher than that achieved by commonly used matrix-assisted laser desorption/ionization (MALDI) imaging protocols. The data from imaging experiments were supported by independent LDI-TOF/MS analysis of cryo-sectioned, laser-microdissected and freshly cut plant material. The results confirmed the suitability of combining laser microdissection (LMD) and LDI-TOF/MS or LDI-MSI to analyse localized plant secondary metabolites. Furthermore, Arabidopsis thaliana was analysed to demonstrate the feasibility of LDI-MSI for other commonly occurring compounds such as flavonoids. The organ-specific distribution of kaempferol, quercetin and isorhamnetin, and their glycosides, was imaged at the cellular level.

Phenolics metabolism in insects: Pieris brassicae-Brassica oleracea var. costata ecological duo

Changes in the phenolics composition of Pieris brassicae larvae fasted for distinct periods (1, 2, 4, 6, and 8 h) and their excrements and of Brassica oleracea L. var. costata DC leaves were determined by high-pressure liquid chromatography/UV-photo diode array detector/mass spectrometry-electrospray ionization. This is the first report following phenolics' metabolism by P. brassicae through time. The results evidence that P. brassicae sequesters and metabolizes the phenolic compounds from the host plant. In a general way, deacylation was the main metabolic reaction that took place, but deglycosylation and sulfate conjugation reactions also occur. Additionally, several kaempferol derivatives containing rhamnose, which is not common in Brassica, were found in the host plant. Attending to the bioactivities recognized for the type of identified compounds, the different materials may constitute an interesting source of bioactive compounds, namely, of highly glycosylated and acylated kaempferol and quercetin derivatives, constituting an economic advantage for producers who have great losses caused by this pest. In addition, a deeper understanding of phenolics metabolism in insects was pursued.

Flavonoid composition and antioxidant activity of tree peony (Paeonia section moutan) yellow flowers

Tree peony flowers are edible and traditional Chinese medicine materials. In the present study, 26 flavonoids were identified and quantified in yellow flowers of tree peony by high-performance liquid chromatography with diode array detector (HPLC-DAD) and by HPLC-electrospray ionization-mass spectrometry (HPLC-ESI-MS). Seventeen of them were first reported in flowers of tree peony, and glycosides of kaempferol, luteolin, and apigenin as well as isosalipurposide were the main flavonoids investigated. Furthermore, the petal extracts showed high antioxidant activity according to DPPH*, ABTS*(+), and OH* scavenging assays and ferric reducing antioxidant power assay. There were significant correlations between antioxidant activity and both the total polyphenol content (determined by Folin-Ciocalteu method) and the total content of quercetin, kaempferol, and luteolin glycosides. This work is valuable for elucidation of phenolic composition in tree peony flowers and for further utilization of them as functional food and medicine materials.

Endothelial function and cardiovascular disease: Effects of quercetin and wine polyphenols

Endothelial dysfunction is an early pathophysiological feature and independent predictor of poor prognosis in most forms of cardiovascular diseases. Epidemiological studies report an inverse association between dietary flavonoid consumption and mortality from cardiovascular diseases. In the present paper, we review the effects of flavonoids, especially quercetin and wine polyphenols, on endothelial function and dysfunction and its potential protective role in hypertension, ischemic heart disease and stroke. In vitro studies show that flavonoids may exert multiple actions on the NO-guanylyl cyclase pathway, endothelium-derived hyperpolarizing factor(s) and endothelin-1 and protect endothelial cells against apoptosis. In vivo, flavonoids prevent endothelial dysfunction and reduce blood pressure, oxidative stress and end-organ damage in hypertensive animals. Moreover, some clinical studies have shown that flavonoid-rich foods can improve endothelial function in patients with hypertension and ischemic heart disease. Altogether, the available evidence indicates that quercetin and wine polyphenols might be of therapeutic benefit in cardiovascular diseases even though prospective controlled clinical studies are still lacking.

Quercetin is bioavailable from a single ingestion of grape juice

The in vivo bioactivity of polyphenols will depend on their bioavailability. Grape juice is an important source of dietary phenolics. This paper reports results that prove that quercetin (3,3',4',5,7-pentahydroxyflavone) is bioavailable after a single ingestion of red grape juice by healthy volunteers. Blood plasma samples were collected before and after 2 h of ingestion of 100 ml of concentrated grape juice (n = 14), and of a placebo solution (n =6). Significant differences in the variation of the total plasma quercetin content (before and after ingestion) between the grape juice ingestion group (3.1 microg/l increase, as a mean) and the placebo group (6.0 microg/l decrease, as a mean) were found. This relatively low increase in comparison with that obtained after 2 h of ingestion of onions (201 microg/l, as a mean) and with those reported in the literature for other foods/beverages was attributed to differences in the amount of quercetin ingested, in the form in which quercetin is present, and in the food matrix.

Practical guidelines for characterization of O-diglycosyl flavonoid isomers by triple quadrupole MS and their applications for identification of some fruit juices flavonoids

Fifteen flavonoid O-diglycosides with different interglycosidic linkage isomery and glycosylation position have been studied in order to analyze their fragmentation patterns. Initial separation was carried out using high performance liquid chromatography with diode array detection (HPLC/DAD) coupled to an electrospray ionization (ESI) interface and a triple quadrupole mass spectrometer. Some useful differences in their MS spectra have been found and discussed. As it has already been reported, [Y*]+/[Y0]+ ratio for flavanones and [Y1]+/[Y0]+ ratio for other flavonoids is specific for each isomeric interglycosidic linkage. In this work it has also been observed that the abundance of these ions is dependent on the position of glycosylation. On the basis of these differences, systematic guidelines for our experimental conditions have been proposed for the differentiation of not only isomeric interglycosidic linkage but also glycosylation position using collision-induced dissociation MS/MS (CID-MS/MS) spectra in positive mode. These results have been successfully applied for the characterization of three diglycosyl flavonoids found in Citrus fruit juices and these conclusions have also been extrapolated for characterizing two triglycosides in the same fruits.

Validated high-throughput HPLC method for the analysis of flavonol aglycones myricetin, quercetin, and kaempferol in Rhus coriaria L. using a monolithic column

A rapid and simple reversed-phase high-performance liquid chromatographic method using a monolithic column was developed and validated for the separation and quantification of myricetin, quercetin, and kaempferol in Rhus coriaria L. The method employed the isocratic mobile phase acetonitrile-10 mM potassium dihydrogen orthophosphate buffer adjusted to pH 3.0 using orthophosphoric acid (38 + 62, v/v) at a flow rate of 4.0 mL/min; a Chromolith Performance RP-18e (100 x 4.6 mm) monolithic column kept at 40 degrees C; and UV detection at 370 nm. Although the elution order was identical and the selectivity was equivalent, the comparison between monolithic and particulate columns showed that the monolithic column could reduce the separation time to < 1 min without sacrificing column efficiency and selectivity. The method was validated according to International Conference on Harmonization guidelines. The validation characteristics included accuracy, precision, linearity, range, specificity, LOQ, and robustness. The calibration curves were linear (r > 0.999) over the concentration range of 0.88-88.3 micro/mL for myricetin, 0.95-95 microg/mL for quercetin, and 1.43-143.3 microg/mL for kaempferol. The recoveries for all three compounds were above 89%. Myricetin was found to be the major flavonol in the examined plant extracts, followed by minor quantities of quercetin and kaempferol.

[Detection of polymeric forms of dihydroquercetin by optical absorption and light scattering]

Two methods for the detection of long polymers in dihydroquercetin (DHQ) preparations has been developed. The first method is based on UV spectrophotometry. It was shown that the quantity of long polymers in aqueous solutions can be estimated by the ratio of the absorption bands at 328 and 290 nm, since the 328-nm band was attributed to the monomeric form of DHQ, whereas the 290-nm band was attributed to both the monomeric and polymeric forms. The second method is based on the high-sensitive measurement of light-scattering intensity in aqueous solutions of diluted DHQ preparations using a spectrofluorometer with crossed monochromators. It has been shown that the filtration of DHQ solutions through Millipore filters with a pore diameter of 0.05-0.45 microns makes it possible to nearly completely eliminate long polymers and their aggregates. Long polymers at high concentrations can aggregate. The longest polymers and their aggregates may be 0.1 mm in length, which leads to fluctuations in the light-scattering intensity on the second and minute time scale.

Level of catechin, myricetin, quercetin and isoquercitrin in buckwheat (Fagopyrum esculentum Moench), changes of their levels during vegetation and their effect on the growth of selected weeds

Buckwheat is well-known as a crop rich in flavonoids, however, attention has usually only been paid to the main flavonoid rutin as an important natural antioxidant or as a possible allelopathic compound. Therefore, some of the other constituents found within individual plant parts of buckwheat (isoquercitrin, quercetin, catechin, and myricetin), as well as changes of their level during the growing season, were determined by HPLC analysis. The effects of these compounds on plant growth were proved on seven plant species. In buckwheat, isoquercitrin represented the largest component of the selected compounds. The strongest inhibitive effects on the growth of those selected plants were produced by catechin. Quercetin and isoquercitrin had weak inhibitive effects. Myricetin did not show any influence on plant growth. Hence we suppose that myricetin, isoquercetin and quercetin do not have important function in allelopathy of buckwheat. Buckwheat as row material for functional foods could be a significant source of another antioxidant, isoquercitrin.

Characterization and quantification of flavonoids and hydroxycinnamic acids in curly kale (Brassica oleracea L. Convar. acephala Var. sabellica) by HPLC-DAD-ESI-MSn

Kale is a leafy green vegetable belonging to the Brassicaceae family, a group of vegetables including cabbage, broccoli, cauliflower, and Brussels sprouts, with a high content of health-promoting phytochemicals. The flavonoids and hydroxycinammic acids of curly kale ( Brassica oleracea L. ssp. oleracea convar. acephala (DC.) Alef. var. sabellica L.), a variety of kale, were characterized and identified primarily through HPLC-DAD-ESI-MS(n) analysis. Thirty-two phenolic compounds including glycosides of quercetin and kaempferol and derivatives of p-coumaric, ferulic, sinapic, and caffeic acid were tentatively identified, providing a more complete identification of phenolic compounds in curly kale than previously reported. Moreover, three hydroxycinnamic acids and one flavonoid with an unusual high grade of glycosylation, quercetin-3-disinapoyl-triglucoside-7-diglucoside, have been tentatively identified for the first time. The influence of different extraction conditions (extraction method, solvent type, solvent/solid ratio, and duration of extraction) was investigated. The total flavonol and hydroxycinnamic acid contents in curly kale determined as rutin equivalents (RE) were 646 and 204 mg of RE/100 g of fresh weight (fw), respectively. The contents of individual flavonoids ranged from 2 to 159 mg of RE/100 g of fw, with main compounds kaempferol-3-sinapoyl-diglucoside-7-diglucoside (18.7%) and quercetin-3-sinapoyl-diglucoside-7-diglucoside (16.5%). After acidic hydrolysis, two flavonol aglycones were identified in curly kale, quercetin and kaempferol, with total contents of 44 and 58 mg/100 g of fw, respectively.

[Determination of quercitrin in Polygonum capitatum and relinqing granules by HPLC]

OBJECTIVE

To establish an HPLC method for determination the contents of quercitrin in Polygonum capitatum and Relinqing granules.

METHOD

The samples were analyzed on a Diamonsil C18 colunm (4.6 mm x 250 mm, 5 microm) eluted with the mobile phase consisted of methanol-1% HAc-THF. The flow rate was 1.0 mL x min-m. The detection wavelength was set at 258 nm and the column temperature was 25 degrees C.

RESULT

The calibration curve was linear in the range of 0. 081 64-0.4084 microg (r = 0.99997). The average recovery rate of quercitrin in P. capitatum was 102.3% (RSD 0.99%), and was 102.7% (RSD 2.2%) in Relinqing granules.

CONCLUSION

The method is reliable and specific with good repeatability, and can be used for the quality control of P. capitatum and Relinqing granules. It can provide a science bases for the planting of polygonum capitatum.

[Study on extraction of quercetin in guava leaf by microemulsion]

OBJECTIVE

To study the extraction of quercetin in guava leaf by microemulsion.

METHODS

The optimal component proportion was obtained by investigating the ratio of oil, water, surfactant and cosurfactant. The extraction of quercetin in microemulsion was determined by HPLC which compared with the traditional method.

RESULTS

The traditional solvent extraction methods were used to extract quercetin in guava leaf, and the content of quercetin extracted with methanol was the highest (4.72 microg/mL). But the contents of quercetin extracted by 72 percent of the microemulsions were higher than methanol, and the extraction by the optimum formulation of microemulsion which consisted of acetoacetate (oil phase) -30% avantin solution (water phase) -RH60 (surfactant) was 2 times as much as that was extracted by methanol (10.43 microg/mL).

CONCLUSION

Compared with traditional solvent extraction methods, microemulsion method can effectively improve the extraction rate of quercetin in guava leaf.

Rutin and total quercetin content in amaranth (Amaranthus spp.)

The aim of the study was to confirm the presence of rutin, one of the most common quercetin glycosides, and other quercetin derivatives in plants of genus Amaranthus, to investigate the influence of the species and variety on rutin distribution in the plant and content changes during growing season. The rutin content was determined by micellar electrokinetic capillary chromatography in individual plant parts at the beginning of the growth, at the flowering stage and at the maturity stage of five Amaranthus species. The total quercetin content was determined by micellar electrokinetic capillary chromatography too. The rutin content in amaranth ranged from 0.08 (in seeds) to 24.5 g/kg dry matter (in leaves). Comparison of the determined total quercetin content and the calculated content of quercetin released from rutin did not prove important presence of quercetin or other quercetin derivatives than rutin. Only amaranth leaves sampled at the maturity stage probably contained quercetin or quercetin derivatives. Significant differences in the rutin content were established among species and as well varieties. Amaranthus hybrid and A. cruentus were the best sources of rutin.

[Phytochemical investigation of Juniper rufescens leaves and fruits]

Seven species of juniper grow in Azerbaijan. The examination of leaves and fruits of Juniperus oxycedrus L. growing in Azerbaijan was conducted. It was found that Juniperus oxycedrus L is widespread in Azerbaijan. The biologically active substances of Juniperus oxycedrus leaves have been studied. It was found that the main biologically active substances in leaves are flavonoids -1,61% and lipids -57,8%; in fruits - ethereal oil 1,2%. The flavonoid composites include luteolin, kaempferol, quercetine, izoquercitrin, rutin. They also possess the diuretic and anti-inflammation effects. Ethereal oil of fruits consist of 20 components, prevailing are alpha-beta-pinen, alpha-fellandren, alpha-terpineol and it also possesses high antimicrobial and antibacterial effect. Lipoid fraction includes tokoferols, karotinoids, xlorofils and lipoid acids: linol, linolen, olein, stearin and palmithin. There are also macroelements K,Ca, Mg,Na,and mikroelements Si, Fe, Al. It was found that the period of maximum accumulation of flavonoids in leaves and ethereal oil in fruit is in Autumn in the period of fruit maturation and ripening. Juniperus oxycedrus L is a good material for new antiseptic remedy. Flavonoids from the leaves of Juniperus oxycedrus L have anti-inflammatory and diuretic effect; fungicide, antimicrobial and antibacterial characteristics.

Quantitative determination of flavonoids by column high-performance liquid chromatography with mass spectrometry and ultraviolet absorption detection in Artemisia afra and comparative studies with various species of Artemisia plants

A simple and specific analytical method for the quantitative determination of flavonoids from the aerial parts of the Artemisia afra plant samples was developed. By column high-performance liquid chromatography (HPLC) with UV absorption and mass spectrometry (MS) detection, separation was achieved on a reversed-phase octadecylsilyl (C18) column with water, methanol, and acetonitrile, all containing 0.1% acetic acid, as the mobile phase. These methods were used to analyze various species of Artemisia plant samples. The wavelength used for quantification of flavonoids with the diode array detector was 335 nm. The limits of detection (LOD) by HPLC/MS were found to be 7.5, 7.5, 10, 2.0, and 2.0 ng/mL; and by LC-UV the LODs were 500, 500, 500, 300, and 300 ng/mL for apigenin, chrysoeriol, tamarixetin, acacetin, and genkwanin, respectively. The HPLC/MS method was found to be 50-150 times more sensitive than the HPLC-UV method. HPLC/MS coupled with an electrospray ionization interface is described for the identification and quantification of flavonoids in various plant samples. This method involved the use of the [M+H]+ ions of the compounds at mass-to-charge ratio of 1.0606, 301.0712, 317.0661, 285.0763, and 285.0763 (calculated mass), respectively, in the positive ion mode with extractive ion monitoring.