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Determination of Bioactive Compounds and Mineral Substances in Latvian Birch and Maple Saps


Birch and maple saps contain carbohydrates and organic acids, B complex vitamins and vitamin C, tannins, flavonoids, glycosides and mineral substances. The aim of the study was to quantitatively determine the concentrations of bioactive compounds and mineral substances in Latvian birch (Betula pendula Roth.) and maple (Acer platanoides L.) saps. Electrical conductivity was determined (629 and 967 S/cm in birch and maple saps, respectively) to characterise the total amount of mineral substances. In birch and maple saps the titratable acidity (0.50 and 0.70 mmol of NaOH per litre of sap, respectively) and formol number (0.25 and 0.20 mmol NaOH per litre of sap, respectively) were determined. The protein concentration was found to be higher in maple sap (171 and 127 mg/l, respectively). The antioxidant concentration, determined using quercetin as a standard, was 0.35 mg of quercetin equivalents (QE)/l in birch sap and 0.77 mg QE/l in maple sap. In conclusion, Latvian maple sap contains more bioactive and mineral compounds than birch sap. Latvian birch sap contains up to 20% more glucose and fructose than birch sap produced in Finland, but Latvian maple sap contains 10 to 40% less sucrose than sap produced in North America.

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Modifications of nitric oxide production in rat tissues by ellagic acid, ipriflavone and resveratrol: a comparative study

.G. (2005). Resveratrol, an extract of red wine, inhibits lipopolysaccharide induced airway neutrophilia and inflammatory mediators through an NF-kappaB-independent mechanism. FASEB J. , 19 (7), 840-841. Chen, C.K., Pace-Asciak, C.R. (1996). Vasorelaxing activity of resveratrol and quercetin in isolated rat aorta. Gen. Pharmacol. , 27 (2), 363-366. Cíz, M., Pavelkovį, M., Gallovį, L., Krįlovį, J., Kubala, L., Lojek, A. (2008). The influence of wine polyphenols on reactive oxygen and nitrogen species production by

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Influence of Steam Treatment and Drying on Carrots Composition and Concentration of Phenolics, Organic Acids and Carotenoids

-performance liquid chromatography. J. Chromatogr. A , 913 , 387–395. Dall’Acqua, S., Miolo, G., Innocenti, G., Caffieri, S. (2012). The photodegradation of quercetin: Relation to oxidation. Molecules , 17 , 8898–8907. Erkan, N., Cetin, H., Ayranci, E. (2011). Antioxidant activities of Sideritis congesta Davis et Huber-Morath and Sideritis araguta Boiss et Heldr: Identification of free flavonoids and cinnamic acid derivatives. Food Res. Int., 44 , 297–303. Garcia-Salas, P., Morales-Soto, A., Segura-Carretero, A., Fernandez-Gutierrez, A. (2010). Phenolic

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Sea Buckthorn Vegetative Parts – A Good Source of Bioactive Compounds

, R. S., Tappia, S. P., Dhalla, N. S. (2011). Health benefits of sea buckthorn for the prevention of cardiovascular diseases. J. Funct. Foods , 3 , 2-12. Xu, X., Xie, B., Pan, S., Liu, L., Wang, Y., Chen, C. (2007). Effects of sea buckthorn procyanidins on healing of acetic acid-induced lesions in the rat stomach. Asia Pac. J. Clin. Nutr ., 16 (1), 234-238. Zu, Y., Li, C., Fu, Y., Zhao, C. (2006). Simultaneous determination of catechin, rutin, quercetin kaempferol and isorhamnetin in the extract of sea buckthorn ( Hippophae

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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)


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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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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The Contribution of Sucrose Esters to Tobacco Smoke Composition

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.

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