High-Performance Liquid Chromatography Characterization and Identification of Antioxidant Polyphenols in Maple Syrup

Abstract

Maple syrup of four grades (extra-light, light, medium, and dark) of the 2007 crop was provided by three local (St. Joseph's Island, Ontario, Canada) producers. Twenty-four phenolic compounds were isolated from a medium-grade syrup and identified on the basis of spectral and chemical evidence. They were (a) benzoic acid and several hydroxylated and methoxylated derivatives (gallic acid, 1-Ogalloyl-β-D-glucose, γ -resorcylic acid); (b) cinnamic acid derivatives (p-coumaric acid, 4-methoxycinnamic acid, caffeic acid, ferulic acid, sinapic acid, and the ester chlorogenic acid); (c) flavonoids, the flavanols catechin and epicatechin, and the flavonols kaempferol and its 3-O-β-D-glucoside, 3- O-β-D-galactoside, quercetin and its 3-O-β-D-glucoside, 3-O-β-L-rhamnoside and 3-O-rhamnoglucoside (rutin).Traces obtained at 280 and 350 nm in HPLC runs of the ethyl acetate-soluble fractions of eight samples indicated the presence of many more phenolic substances, most at very low concentration with some varibilities in peak heights, but not in retention times, among the syrups. In view of the well-established antioxidant activity these substances possess, it is suggested that it is the complexity of the mixture rather than any one compound that may serve to counter the unhealthful presence of the high concentration of sugars in the syrup.

Chemotaxonomic Metabolite Profiling of 62 Indigenous Plant Species and Its Correlation with Bioactivities

“…Furthermore, gallic acid and flavonoids were major polyphenols in plants in the Fagaceae family, which contribute to antioxidant activity [41,42]. Similar to the Betulaceae and Fagaceae, Aceraceae species were reported to exhibit antioxidant activity due to various phenolic compounds, such as quercetin, kaempferol, and flavonoid derivatives [43]. These results suggested that the relatively high contents of bioactive compounds in Aceraceae, Betulaceae, and Fagaceae might contribute to the high bioactivity of those families.…”

In vitro evaluation of phenolic-enriched maple syrup extracts for inhibition of carbohydrate hydrolyzing enzymes relevant to type 2 diabetes management

“…Maple syrup is produced primarily in North America with the vast majority of the world's supply coming from Canada (85%; primarily Quebec), followed by United States (Perkins & van der Berg, 2009). Previous reports have shown that maple syrup contains a wide variety of phenolic phytochemicals (Abou-Zaid, Nozzolillo, Tonon, Coppens, & Lombardo, 2008;Filipie & Underwood, 1964;Kermasha, Goetghebeur, & Dumont, 1995;Li & Seeram, 2010;Potter & Fagerson, 1992), which may have positive effects on human health. Recently, phenolic-enriched extracts of maple syrup were shown to have antioxidant, anti-mutagenic and human cancer cell anti-proliferative properties (Legault, Girard-Lalancette, Grenon, Dussault, & Pichette, 2010;Li & Seeram, 2010;Theriault, Caillet, Kermasha, & Lacroix, 2006).…”

Seasonal influence on phenolic-mediated antihyperglycemic properties of Canadian sugar and red maple leaves using in vitro assay models

“…Previous reports have shown that maple syrup contains a wide variety of phenolic phytochemicals (11)(12)(13), which may have positive effects on human health, including potential for type 2 diabetes management via inhibition of the carbohydrate hydrolyzing enzyme α-glucosidase (7).…”