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Evaluation of the antioxidant activity of extracts and flavonoids obtained from Bunium alpinum Waldst. & Kit. (Apiaceae) and Tamarix gallica L. (Tamaricaceae)

Abstract

The aim of the present work was to evaluate the antioxidant activity of extracts and four flavonoids that had been isolated from the aerial parts of Bunium alpinum Waldst. et Kit. (Apiaceae) and Tamarix gallica L. (Tamaricaceae). In this work, the four flavonoids were first extracted via various solvents, then purified through column chromatography (CC) and thin layer chromatography (TLC). The four compounds were subsequently identified by spectroscopic methods, including: UV, mass spectrum 1H NMR and 13C NMR. The EtOAc extract of Bunium alpinum Waldst. et Kit yielded quercetin-3-O-β-glucoside (3’,4’,5,7-Tetrahydroxyflavone-3-β-D-glucopyranoside) (1), while the EtOAc and n-BuOH extracts of Tamarix gallica L. afforded 3,5,3’-trihydroxy-7,4’-dimethoxyflavone (2), 3,5,7-trihydroxy-4’-methoxyflavone (3) and 5-hydroxy-3,7,4’-trimethoxyflavone (4). The antioxidant activity of the extracts and the flavonoids were then evaluated through DPPH free radical-scavenging assay. Of all studied extracts, the n-Butanol extract of Bunium alpinum (EC50 = 1.84 μg/ml) showed the best antioxidant activity against (DPPH). In contrast, the isolates demonstrated varying degrees of antioxidant activity: compound (1) was the more active (EC50 = 0.28 μg/ml), followed by compound (3) and (2) (EC50 = 0.309μg/ml, EC50 = 0.406 μg/ml, respectively), compound (4) showed the lowest activity. All the isolated flavonoids exhibited antioxidant activity, but this was lower than the control (Trolox). In conclusion, due to the presence of flavonoids in their ariel parts, the studied plants could be natural sources of several important antioxidant agents

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Analysis of the Polyphenols of Tobacco Using Pressurized Liquid Extraction (PLE) and Ultra Performance Liquid Chromatography With Electrospray Ionization – Tandem Mass Spectometric Detection (UPLC-ESI-MS/MS)

Summary

Polyphenols are chemicals found in tobacco that are affected by the method used to cure the leaf and, as a result, can be useful in the characterization of tobacco products. The purpose of this work was to develop an analytical method to investigate the levels of six polyphenols found in tobacco leaves and tobacco products: 3-O-caffeoylquinic acid (chlorogenic acid), 4-O-caffeoylquinic acid (cryptochlorogenic acid), 5-O-caffeoylquinic acid (neochlorogenic acid), kaempferol 3-O-rutinoside (nicotiflorin), quercetin 3-O-rutinoside (rutin), and 6-methoxy-7-hydroxycoumarin (scopoletin). Extraction conditions for sample preparation using PLE and instrument conditions for analysis by UPLC-MS/MS were optimized and validated. Results from the analysis of 30 cured tobacco leaves are presented and discussed in the context of each curing method represented. Results from the analysis of various tobacco products are also presented and trends observed across product types are discussed in the context of the applicability of the validated method. Total polyphenol levels for flue-cured, Oriental, and air-cured leaves were determined to be in the ranges of 18–41 mg/g, 5–27 mg/g, and 0.5–3 mg/g respectively. Similarly, cigarette polyphenol levels were found in the range of 4–16 mg/g and cigar polyphenol levels were less than 1.5 mg/g. The trends observed in the results for the tobacco leaf samples are consistent with expectations regarding the fate of polyphenols under the conditions commonly used in curing procedures. The results for the tobacco products demonstrate that the validated method can be used to study polyphenol content in cigarettes and a variety of cigar types including pipe tobacco cigars.

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Experimental Paper. Intrapopulation variability of flavonoid content in roots of Baikal skullcap (Scutellaria baicalensis Georgi)

Summary

Introduction: Baikal skullcap (Scutellaria baicalensis Georgi) is an important medicinal plant, indigenous to Asia. Due to a wide range of pharmacological activities, its roots has been used for ages in Traditional Chinese Medicine. Recently, the species has become an object of interest of Western medicine, as well. Objective: The aim of the study was to determine the variability of Baikal skullcap population originated from Mongolia and cultivated in Poland, in terms of content and composition of flavonoids in the roots. Methods: The objects of the study were 15 individual plants, selected within examined population and cloned in order to obtain a sufficient amount of raw material. The total content of flavonoids in roots was determined according to Polish Pharmacopeia 6th. The qualitative analysis of flavonoids was carried out using HPLC, Shimadzu chromatograph. Results: The dry mass of roots ranged from 25.88 to 56.14 g × plant-1. The total content of flavonoids (expressed as a quercetin equivalent) varied between 0.17 and 0.52% dry matter (DM). Nine compounds were detected within the group, with oroxylin A 7-Oglucuronide (346.90-1063.00 mg × 100 g-1 DM) as a dominant, which differentiated investigated clones at the highest degree (CV=0.27). Baicalin (391.40-942.00 mg × 100 g-1 DM), wogonoside (324.00-641.10 mg × 100 g-1 DM) and hesperetine 7-O-glucoside (163.00-346.32 mg × 100 g-1 DM) were also present in a considerable amounts. Clone 7 was distinguished by the highest content of all investigated compounds, except wogonin and oroxylin A 7-O-glucuronide. Conclusions: Results obtained in present study show a high variability within Baical skullcap investigated population in respect of flavonoid compounds detected in roots. Thus, the results may be used in future investigations concerning the selection and breeding of this species.

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Yield and level of phenolic compounds in the inflorescence of yellow everlasting Helichrysum arenarium (L.) Moench collected from natural sites

Summary

Introduction: The inflorescence of Helichrysum arenarium (L.) Moench shows anti-inflammatory, antioxidant, detoxifying properties and is traditionally used in liver and biliary tract diseases. Because of its difficult and expensive cultivation, the plant raw material is mainly harvested from natural sites.

Objective: The research aimed to determine the local variation in yield and content of flavonoids and phenolic acids in the yellow everlasting inflorescence against the background of the layer structure of vegetation as the rate of plant succession.

Methods: The plant raw material was collected from 30 plots of 1 m2, established for three separate populations developing on sandy fallows near Zielona Góra (western Poland). For each study area, percentage cover of the moss-lichen and herb layers, the height, cover and yield of H. arenarium as well as the height and cover of other herbaceous plants were determined. Total contents of flavonoids (expressed as quercetin) and phenolic acids (calculated as caffeic acid) were measured spectrophotometrically, according to Polish Pharmacopoeia.

Results: Everlastings reached a cover of up to 70% and the maximum air-dry matter yield of 46.42 g/m2. The height, coverage and yield of H. arenarium were correlated with the parameters describing the herb layer. The content of flavonoids ranged from 0.56 to 0.99%, while that of phenolic acids from 0.82 to 1.80% DM.

Conclusions: Yellow everlasting is an important species of early fallows on poor sandy soils and these habitats constitute a rich natural source of herbal raw material. Inflorescences harvested from natural sites are distinguished by a high and similar content of polyphenols and usually meet the requirements of Polish Pharmacopoeia.

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Chemical composition and antifungal potential of medicinal plants against seedborne mycoflora of eggplant (Solanum melongena L.)

Abstract

Antifungal activities of medicinal plants were observed against seedborne mycoflora of eggplant (Solanum melongena). The effect of ethanolic leaf extracts of Mangifera indica, Mentha spicata, Citrus limon, Eucalyptus camaldulensis against four isolated fungal species including Fusarium oxysporum, Aspergillus flavus, Rhizopus stolonifer and Penicillium digitatum was evaluated at various concentrations, by using the poisoned food technique. The impact of the extracts on seed germination and growth of eggplant was assessed by seed treatment and growth in a greenhouse experiment. Total flavonoids of E. camaldulensis were analyzed through spectrophotometer, using quercetin as a standard. Physico-chemical parameters were also determined. Antifungal activity showed that maximum inhibition percentage of P. digitatum (67.78%) and F. oxysporum (64.44%) was observed at the highest concentration (80%) of C. limon and E. camaldulensis extracts, respectively, followed by M. spicata extract against A. fl avus (63.33%) and R. stolonifer (52.22%). Least inhibition percentage of F. oxysporum, P. digitatum, R. stolonifer and A. flavus was 6.67, 7.78, 14.44 and 16.67%, respectively, at the lowest (20%) concentration of M. spicata. The greenhouse experiment showed variations in seedling germination and post-germination growth. E. camaldulensis extract showed an increase in percent germination (78.98%) over untreated control (62.83%), root and shoot length and fresh and dry weight of root and shoot with the consequent reduction in disease symptoms. Phytochemical analysis depicted the presence of alkaloids, flavonoids, tannins, saponins in all extracts while steroids and glycosides were absent. A fair amount (10.38 mg QE g-1 DF) of flavonoid was present in leaf extract of E. camaldulensis. Physico-chemical analysis showed pH of 4.6, ash content of 0.41% and weight loss on drying of 8.14%.

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Status of rats myocardium under subchronic mercury exposure and its pharmacological correction

REFERENCES 1. Aaseth J. et al.: Chelation in metal intoxication-Principles and paradigms. J Trace Elem Med Biol ., 31, 260-266, 2015. 2. Avtandilov G.G. (1990): Medical morphometry . Guide. Medicine. (in Russian) 3. Ballmann C. et al.: Histological and biochemical outcomes of cardiac pathology in mdx mice with dietary quercetin enrichment. Exp Physiol , 100, 12-22, 2015. 4. Bernhoft R.A.: Mercury toxicity and treatment: a review of the literature. J Environ Public Health ,. 2012, 2012. 5. Busch J. et al.: The heavy metals cadmium

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Antioxidant and Antiradical Properties of Esculin, and its Effect in A Model of Epirubicin-Induced Bone Marrow Toxicity

al. Phenolics as potential antioxidant therapeutic agents: mechanism and actions. J Mutation Research 2005;579(1-2):200-13. 8. Musialik M, Kuzmicz R, Pawłowski TS, et al. Acidity of hydroxyl groups: an overlooked infl uence on antiradical properties of fl avonoids, J Org Chem 2012;74,7:2699-709. 9. Chow H, et al. Quercetin, but not rutin and quercitrin, prevention of H2O2-induced apoptosis via anti-oxidant activity and heme oxygenase 1 gene expression in macrophages. Biochem Pharmacol 2005;69(12):1839-51. 10. Sanchez

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Rapid Spectrophotometric Analysis of the Chemical Composition of Tobacco: Part 3: Polyphenols

. C.: Physiology and biochemistry of tobacco plants; Dowden, Hutchinson & Ross, Inc., Stroudsburg, Pa., p. 259ff., 1972. 8. Williamson, R. E.: Automated calorimetric determination of polyphenols in tobacco leaf; 29th Tobacco Chemists' Research Conference, Beltsville, Maryland, 1975, abstracts, p. 23. 9. Zane, A., and S. H. Wender: Pyrolysis products of rutin, quercetin, and chlorogenic acid; Tob. Sci. 7 (1963) 21-23.

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Determination of kaempferol in extracts from Lilium candidum L. Liliaceae by means of liquid chromatography

quercetin, kaempferol and ( E ) -cinnamic acid in vegetative organs of Schisandra chinensis Baill. by HPLC. J Pharm Biochem Anal. 2001;24:1049-1054. Smělá M. Možnosti stanovenia flavonoidov. Bakalárska práca. Brno: VUT, Chemická fakulta. 2009. Vachálková A, Eisenreichová E, Haladová M, Mučaji P, Jóžová B, Novotný L. Potencial carcinogenic and inhibitory activity of compounds isolated from Lilium candidum L. Neoplasma, 2000;47:313-318. Vitková Z, Grančai D, Haladová M, Herdová P, Cupáková M

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Modulatory effects of rutin on the expression of cytochrome P450s and antioxidant enzymes in human hepatoma cells

cancer, Pharmacol. Rev. 52 (2000) 673-751. 6. G. Williamson and C. Manach, Bioavailability and bioefficacy of polyphenols in humans. II. Review of 93 intervention studies, Am. J. Clin. Nutr. 81 (2005) 243S-255S. 7. B. A. Graf, C. Ameho, G. G. Dolnikowski, P. E. Milbury, C. Y. Chen and J. B. Blumberg, Rat gastrointestinal tissues metabolize quercetin, J. Nutr. 136 (2006) 39-44. 8. S. Scholz and G. Williamson, Interactions affecting the bioavailability of dietary polyphenols in vivo, Int. J. Vitam. Nutr.Res. 77 (2007) 224

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