INFLUENCE OF VARIETAL AND pH VARIATION ON ANTIHYPERGLYCEMIA AND ANTIHYPERTENSION PROPERTIES OF LONG-TERM STORED APPLES USING IN VITRO ASSAY MODELS

Abstract

This study provides further in vitro evidence for inhibition by apple extracts of alpha‐glucosidase and alpha‐amylase for potential antihyperglycemia benefits and angiotensin converting enzyme inhibitory activity for associated antihypertension potential. This was investigated in peel and pulp aqueous and ethanol extracts from 10 different long‐term stored apple cultivars. “Red Delicious” and “Cortland” cultivars had significantly higher total phenolic content and inhibitory antioxidant capacity, with high correlation between both assays. Quercetin derivatives, catechin, chlorogenic acid and p‐coumaric acid were detected, and the composition and amount varied significantly between aqueous and ethanolic extracts. Red Delicious cultivar had high alpha‐amylase and alpha‐glucosidase inhibitory activities. These phenolic‐linked bioactive potential of apple cultivars indicate that they may impart health benefits when consumed even after long‐term storage and should be considered as valuable source of antioxidants with additional antihyperglycemia potential relevant for the management of early‐stage type 2 diabetes following further clinical studies. PRACTICAL APPLICATION This study explored the potential health benefits of phenolic‐linked antioxidants from long‐term stored apple cultivars and evaluated the association to potential prevention of postprandial hyperglycemia linked to type 2 diabetes using in vitro bioassay models. It was confirmed that the apple cultivar “Red Delicious” and other cultivars commonly consumed in the U.S.A. have relevance for hyperglycemia management, and apples can be included as part of the overall diet in an environment where starch and sugar consumption is increasingly high. This in vitro biochemical rationale from this study provides further phenolic bioactive‐linked, structure–function basis for additional animal and clinical studies to rationalize effective designs of whole foods, fruits and vegetables for long‐term diet‐based management of type 2 diabetes.

Type 2 Diabetes Relevant Bioactive Potential of Freshly Harvested and Long-Term Stored Pears Usingin vitroAssay Models

“…(2010) found that apple peel had higher antioxidant capacity, total phenolic content, alpha‐glucosidase inhibitory activity than pulp, while apple pulp had high alpha‐amylase inhibitory activity. Similar results were observed for long‐term stored apples (Barbosa et al . 2011).…”

“…Both aqueous and ethanolic pulp extracts had low antioxidant capacity (8–29%) when compared with peel extracts. Barbosa et al . 2010, 2011 found similar range for DPPH radical inhibition‐based antioxidant activity and total phenolic content for the apple varieties studied.…”

“…Our previous research showed that apples and others fruits and vegetables have phenolic bioactive factors that have the potential to contribute to the overall management of type 2 diabetes and its associated complications such as hypertension (Kwon et al . 2007a,b, 2008; Barbosa et al . 2010, 2011).…”

Evaluation of Brans of Different Rice Varieties for their Antioxidative and Antihyperglycemic Potentials

“…Many researchers have reported the inhibitory potentials of starch hydrolysing enzymes in a number of plants such as pea nut (Arachis hypogaea) (Irshad and Sharma 1981), cowpea (Piergiovanni and Gatta 1994), lima beans (Phaseolus lunatus) (Johnson et al 2013), white beans (Phaseolus vulgaris) (Barrett and Udani 2011), sorghum (Mulimani and Supriya 1993) and wheat (Heidari et al 2005). According to other reports, blackcurrant, blueberry (McDougall et al 2005), strawberry (Pinto et al 2008), apples (Barbosa and Pinto 2012) and ginger (Oboh et al 2010) also have the ability to inhibit the activity of a-glucosidase. According to other reports, blackcurrant, blueberry (McDougall et al 2005), strawberry (Pinto et al 2008), apples (Barbosa and Pinto 2012) and ginger (Oboh et al 2010) also have the ability to inhibit the activity of a-glucosidase.…”

“…Inhibitory potential of starch hydrolysing enzymes have also been detected in fruits and vegetables such as raspberry (Boath et al 2012), red grape (Mccue et al 2005), green pepper (Mccue et al 2005), cambucci and cupuacu fruits (Pinto et al 2008) and carrots (Mccue et al 2005). According to other reports, blackcurrant, blueberry (McDougall et al 2005), strawberry (Pinto et al 2008), apples (Barbosa and Pinto 2012) and ginger (Oboh et al 2010) also have the ability to inhibit the activity of a-glucosidase.…”