The Nitric Oxide Inducing Activity of Aquilaria Subintegra Tea Extract and Its Microencapsulated Form in Human Vascular Endothelial Cells
DOI:
https://doi.org/10.48048/tis.2026.11325Keywords:
Aquilaria subintegra, Human umbilical vein endothelial cells, Endothelial nitric oxide synthase, Nitric oxideAbstract
Aquilaria subintegra leaves are rich in polyphenols and flavonoids with antioxidant properties. Aquilaria spp. leaf tea is gaining attention for its health benefits; however, its effects on cardiovascular health remain underexplored. This study examined the effects of A. subintegra tea extract (AS extract) and microencapsulation on nitric oxide (NO) production in human umbilical vein endothelial cells (HUV-EC-C). Dried leaves were extracted using hot water, freeze-dried, and tested for cytotoxicity (MTT assay), NO production (Griess assay), and expression of endothelial nitric oxide synthase (eNOS and phospho-eNOS) (western blot). The extract was microencapsulated in maltodextrin-DE10 and freeze-dried. The results showed that a 30-minute extraction yielded the highest phenolic and flavonoid contents. AS extracts (10 - 100 µg/mL) were non-toxic and significantly enhanced NO production at 40, 80 and 100 µg/mL (p < 0.05). AS extract (80 and 100 µg/mL) increased eNOS expression and phosphorylation at Ser-1177 within 15 min. Microencapsulation at a 20:1 extract-to-coating ratio had > 80% encapsulation efficiency and induced NO production 1.8 times higher than the control. These findings elucidate the mechanisms underlying the vascular endothelial promotion of A. subintegra tea extract through NO synthesis. This suggests that A. subintegra tea extract and its microencapsulated form effectively promote NO synthesis, supporting its potential as a functional ingredient for cardiovascular health.
HIGHLIGHTS
- Aquilaria subintegra tea extract (AS extract) significantly stimulated nitric oxide (NO) production in endothelial cells with increased eNOS expression and phosphorylation at Ser-1177, suggesting potential vascular health benefits.
- Microencapsulation using maltodextrin DE-10 retained over 80% of the bioactive compounds and its NO-inducing activity in endothelial cells, ensuring stability and bioavailability.
- These findings support the development of subintegra tea as a functional ingredient for vascular health and provide a scientific basis for its nutraceutical and therapeutic applications.
GRAPHICAL ABSTRACT
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