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Sylwia Cyboran, Dorota Bonarska-Kujawa, Ireneusz Kapusta, Jan Oszmiański and Halina Kleszczyńska

characteristics of hemoglobin-free ghosts of erythrocytes. Arch. Biochem. , 100 , 119-130. Droge W. (2002). Free radicals in the physiological control of cell function. Physiol. Rev. , 82 (1), 47-95. Ferrali M., C. Signorini C., Caciotti B., Sugherini L., Ciccoli L., Giachetti D. & Comporti M. (1997). Protection against oxidative damage of erythrocyte membrane by the flavonoid quercetin and its relation to iron chelating activity. FEBS Lett.   416 , 123-129. Gąsiorowski K., Szyba K., Brokos B

Open access

John R. Shifflett, Leah Watson, Devin J. McNally and Dawit Z. Bezabeh

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.

Open access

W.F. McClure and R.E. Williamson

. 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.

Open access

WS Schlotzhauer, RF Severson and RM Martin

rutin, quercetin, and chlorogenic acid; Tob. Sci. 7 (1963) 21-23. 20. Schlotzhauer, W. S., R. M. Martin, M. E. Snook and R. E. Williamson: Pyrolytic studies on the. contribution of tobacco leaf constituentS to the formation of smoke catechols; J. Agric. Food Chem. 30 (1982) 372-374.

Open access

Tian Gao, Min Zhang, Zhongxiang Fang and Qifeng Zhong

Regelson W., 1995. Review of the biology of quercetin and related bioflavonoids. Food Chemical Toxicology, 33(12), 1061-1080. Kamiyama M. and Shibamoto T., 2012. Flavonoids with potent antioxidant activity found in young green barley leaves. J. Agric. Food Chem., 60(25), 6260-6267. Liu J. and Zhou R.Q., 2005. Improvement of determination method of total flavonoids from bamboo leaves. Food Technology, 76-79. Markham K.R. and Mitchell K.A., 2003. The mis-identification of the major antioxidant flavonoids in young barley ( Hordeum vulgare ) leaves

Open access

Peter M. Eze, Joy C. Nnanna, Ugochukwu Okezie, Happiness S. Buzugbe, Chika C. Abba, Chidimma R. Chukwunwejim, Festus B. C. Okoye and Charles O. Esimone

References 1. Strobel G. The Emergence of Endophytic Microbes and Their Biological Promise. J. Fungi 2018; 4(2): 57 2. Ebada SS, Eze P, Okoye FBC, Esimone CO, Proksch P. The fungal endophyte Nigrospora oryzae produces quercetin monoglycosides previously known only from plants. Chemistry Select 2016; 1(11): 2767-2771. 3. Uzor PF, Ebrahim W, Osadebe PO, Nwodo JN, Okoye FB, Müller WEG, Lin WH, Liu Z, Proksch P. Metabolites from Combretum dolichopetalum and its associated endophytic fungus Nigrospora oryzae -Evidence for a metabolic partnership

Open access

Ouroud Fellah, Samir Hameurlaine, Noureddine Gherraf, Amar Zellagui, Tahar Ali, Abdennabi Abidi, Muhammed Altun, Ibrahim Demirtas and Ayse SahinYaglioglu

Abstract

The aerial parts of T. gallica collected from three different locations (arid, humid and semi-arid) were extracted using ethyl acetate. The crude extracts were subjected to phenolic appraisal and antiproliferative activity using ELISA and xCELLigence assays. The total phenolic and flavonoids were evaluated using appropriate techniques to give a yield of total phenolics ranging between 238.46 and 348.56 mg GAE (Gallic acid equivalent)/g dry weight extract. The flavonoids yield was found to vary from 36.6 to 103.14 mg QE (quercetin equivalent)/g dry weight extract. Moreover, the extracts were tested against rat brain tumor (C6) and human cervix carcinoma (HeLa) cell lines and displayed important differences in activity. These disparities highlighted the effect of climatic factors as quality determinants of secondary metabolites and therefore as a key control of the biological therapeutic effect.

Open access

Ibtissem Boulacel, Brahim Harkati, Radia Ayad, Ibrahim Demirtas, Hocine Laouer and Salah Akkal

Abstract

The focus of this paper was to assess the phytochemical composition, the antioxidant and antibacterial activities of the crude extracts of the aerial parts of Ferula lutea. Four new compounds were isolated from this genus, and their structures were primarily established by extensive spectroscopic analysis including 1D and 2D spectroscopic techniques. Total phenolics and flavonoids containing in ethyl acetate (AcOEt) and n-butanol (n-BuOH) extracts were quantified [199.1-184.02 mg gallic acid equivalent / g of dry weight], flavonoids [70.24-65.95 mg quercetin / g dry weight]. DDPH scavenging and phosphomolybdenum methods were used to evaluate in vitro antioxidant activity. The obtained results showed a significant antioxidant activity of the two aerial parts. Correlation analysis between the DPPH values and those for TAC indicates the possibility of the two models for evaluating antioxidants power from medicinal plants. Dichloromethane (CH2Cl2), AcOEt and n-BuOH extracts were screened against two gram-negative [Escherichia coli (E.coli) and Pseudo aeruginosa (P.aer)] and two gram-positive [Staphylococcus aureus (S.aur) and Bacillus (Bacil.)] bacteria using disc diffusion method. The results indicate a good inhibition of CH2Cl2 and EtAct extracts on the growth of (Bacil. and E.coli). Furthermore n-but extract showed a significant inhibitory effect only against E.coli.