Effective Utilization of Vaccinium virgatum Aiton Stems as Functional Materials: Major Constituent Analysis and Bioactivity Evaluation

Abstract

We previously reported that rabbit-eye blueberry (Vaccinium virgatum Aiton) leaves exhibit multiple functions. In this study, we evaluated whether V. virgatum stems can also be used as functional materials similar to leaves and clarified the major constituents and their biological activity (antioxidant activity and anti–adult T cell leukemia (ATL) activity). Water extracts of V. virgatum stems were separated into 19 fractions using a Diaion HP-20 open column. Sugars and organic acids were detected in the highly water-soluble fractions. Polyphenols and proanthocyanidin were detected in the hydrous methanol-soluble fractions. In biological activity evaluations, a difference in antioxidant activity was observed in the water-containing methanol-eluted fractions, and fractions exhibiting anti-ATL activity differed depending on cell type. These results suggest that blueberry stems, like leaves, are rich in polyphenols and exhibit antioxidant activity and inhibit ATL cell growth. In the future, aerial parts of blueberries, including stems and leaves, could be used as functional materials and/or medicinal resources.

Prediction of the Adult T-Cell Leukemia Inhibitory Activity of Blueberry Leaves/Stems Using Direct-Injection Electron Ionization-Mass Spectrometry Metabolomics

“…The structure of PAC was then identified by liquid chromatography/mass-ion trap-time of flight analysis and butanol-HCl hydrolysis analysis. On the other hand, it was confirmed that PAC was present on the V. virgatum stem by the 4-dimethylaminocinnamaldehyde (DMACA) method in our previous report [ 18 ].…”

“…In our most recent study, we analyzed the fractions obtained from water extracts of V. virgatum stems for the ability to inhibit the proliferation of ATL cell lines [ 18 ]. However, questions regarding which organ contains the most active components, or which is stronger when mixed, have not been rigorously tested in individual plants.…”

“…PACs are polyphenols that exhibit a variety of biological activities, and previous reports suggest that V. virgatum leaves and stems are rich in PACs [ 17 , 18 ]. However, these previous studies differed in terms sampling area and time.…”

“…More recently, we conducted a quantitative analysis of water extracts of V. virgatum stems and found that these plants are rich in polyphenols (included PACs), exhibiting antioxidant activity and inhibiting ATL cell growth [ 18 ]. However, there are no reports of studies comparing the PAC content and functionality of leaves and/or stems in the same individual plant to evaluate the potential for the industrial utilization of blueberry stems and leaves.…”