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

Abstract

Red and sugar maple leaves collected in the summer and fall from Canada, were evaluated for phenolic content, antioxidant, α-glucosidase, and α-amylase inhibitory activities variation. The phenolic contents of summer red maple leaves (RML-S) and summer sugar maple leaves (SML-S) were higher than red and sugar maple leaves collected in fall (RML-F and SML-F, respectively). HPLC analyses showed differences in phenolic compounds present in the SML samples compared to the RML samples. The extracts were assayed for yeast and rat α-glucosidase inhibitory activities. Both results showed that SML-S extracts had the highest inhibitory activity which could possibly be attributed to the unique phenolics present therein. Milder effects were observed in terms of α-amylase inhibitory activity, with RML-F having the highest inhibitory activity. These results suggest that maple tree leaf extracts may have potential for phenolic-mediated α-glucosidase inhibition, relevant to type 2 diabetes management, with SML-S extract having the highest bioactivity.

Blueberry extract inhibits carbohydrate-hydrolyzing enzymes and these inhibitory activities are not proanthocyanidin dependent

“…It is well documented that phenolic phytochemicals have alpha-glucosidase inhibitory activity that depends on the phenolic profile (Kwon et al 2006(Kwon et al , 2007Apostolidis et al 2012). A recent study reported that cinnamon extract has shown non-PAC-dependent rat alpha-glucosidase inhibitory activity (Kang et al 2014).…”

“…Therefore, inhibition of alpha-glucosidases (sucrase and maltase) can be an effective strategy to reduce the glucose absorption in the digestive tract (Krentz and Bailey 2005). It has been reported that certain natural products are potentially good inhibitors of carbohydrate-hydrolyzing enzymes with their effect being attributed to the unique phenolic phytochemicals (Kwon et al 2006(Kwon et al , 2007Apostolidis et al 2012).…”

Antihyperglycemic, antioxidant activities of two Acer palmatum cultivars, and identification of phenolics profile by UPLC-QTOF-MS/MS: New natural sources of functional constituents

“…Attractively, a series of novel compounds, such as maplexin A-F, have been isolated and identified by means of chromatography techniques and elucidation of NMR and ESIMS data . Meanwhile, maple extracts were evidenced to show good antiproliferative (González-Sarrías et al, 2012a,b), antiinflammatory (Nahar et al, 2014), anticancer (González-Sarrías et al, 2013), antihyperglycemic (Apostolidis et al, 2012), and antioxidant activities (Zhang et al, 2015b), especially the potential in preventing diabetes and diabetic complications (Apostolidis et al, 2012;Ma et al, 2015).…”

Antioxidant Capacity, Phenolic Constituents and Toxicity of Hot Water Extract from Red Maple Buds

“…In particular, ginnalins A ( 8 ), B ( 3 ), and C ( 4 ) represent over 75% of the total phenolic content with 41.4%, 11.0%, and 24.4%, respectively. These compounds have already been reported to be the major phenolic compounds identified in red maple leaves, but their concentrations were not reported . Moreover, the antioxidant capacity of these compounds against DPPH · free radical has been evaluated previously .…”

“…These compounds have already been reported to be the major phenolic compounds identified in red maple leaves, but their concentrations were not reported. [11] [27] Moreover, the antioxidant capacity of these compounds against DPPH Á free radical has been evaluated previously. [10] Interestingly, ginnalin A (EC 50 = 17.74 lM), ginnalin B (EC 50 = 32.70 lM), and ginnalin C (EC 50 = 30.49 lM) have all shown a better antioxidant activity than ascorbic acid (EC 50 = 71.02 AE 1.61 lM), a well-known antioxidant standard.…”