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Camu-camu (Myrciaria dubia (Kunth) Mc. Vaugh (Myrtaceae)) has shown potential for food and human health applications due to its rich bioactive functional properties linked to high antioxidant activity. The main objective of this study was to identify antioxidant-linked bioactive phenolic profiles in spray-dried and freeze dried camucamu pulp and to evaluate potential functionality associated with anti-hyperglycemia and anti-hypertension properties using in vitro enzyme assay models. Further, antimicrobial properties and planarian-based cellular protection and regeneration were also investigated. Phenolic compounds, such as ellagitannins, ellagic acid, quercetin glycosides, syringic acid and myricetin were detected in camu-camu by LC-TOF-MS. Freeze dried camucamu powder showed superior phenolic-linked antimicrobial properties and higher hyperglycemia relevant enzyme inhibitory activity compared to the spray dried samples. Besides that, freeze-dried powders and spraydried (6% gum arabic at 120°C) powders were more effective against prokaryotic Staphylococcus aureus and showed higher inhibition than ampicillin. Cellular regeneration of eukaryotic planarian model was stimulated with camu-camu powders when compared to control and showed potential of camu camu for redox-linked cellular protection and rejuvenation. Overall camu-camu rich in phenolic bioactive profiles showed superior antidiabetic and antimicrobial properties and has potential as part of dietary strategies in the management of early stages of type 2 diabetes and associated complications.

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The well-known health benefits of apples have been attributed in part to the presence of polyphenols and related antioxidant capacity. The consumption of apples could provide health benefits by reducing the risk for chronic diseases such as metabolic syndrome disease, including type 2 diabetes. Thus, the objective of this study was to investigate the phenolic-linked antihyperglycemia bioactive factors in aqueous and 12% ethanol extracts of peel and pulp from 10 different freshly harvested apple varieties commonly consumed in the United States. The extracts were analyzed for total soluble phenolics, 2,2-diphenyl-1-picrylhydrazyl-linked antioxidant activity, and their associated in vitro α-glucosidase and α-amylase inhibitory activities. In general, peel extracts had higher total soluble phenolic content and related antioxidant capacity than pulp extracts. Quercetin derivatives, protocatechuic acid, chlorogenic acid, and p-coumaric acid were detected, and the amount varied significantly between aqueous and ethanolic extracts. Honeycrisp and Red Delicious varieties had the highest total phenolic contents and a significant correlation with antioxidant capacity (r = 0.91). In addition, high α-amylase and α-glucosidase inhibitory activities in aqueous pulp extracts were found. However, the peel extracts had the highest α-glucosidase inhibitory activity along with low α-amylase inhibitory activity. No correlation between α-amylase inhibitory activity and total phenolic content was observed. However, positive correlations between α-glucosidase inhibitory activity and total phenolics in aqueous (r = 0.50) and ethanolic (r = 0.70) extracts were observed. This study provides the biochemical rationale for animal and clinical studies to determine the suitable varieties with optimum bioactive factors with antihyperglycemia potential.