Hypertension remains a leading global health challenge, particularly in low- and middle-income countries where non-pharmacological interventions are increasingly sought. Hibiscus sabdariffa L., commonly known as roselle or sour tea, has gained attention for its antihypertensive properties, largely attributed to bioactive compounds such as anthocyanins, phenolic acids, and flavonoids. This review evaluates the influence of extraction methods. Cold maceration and hot decoction shape the phytochemical profile and antihypertensive efficacy of H. sabdariffa in distinct ways. Evidence from in vitro, in vivo, and clinical studies indicates that both extraction methods yield beneficial compounds. Hot aqueous extraction consistently enhances phenolic content and demonstrates superior blood pressure-lowering effects. Mechanisms include angiotensin-converting enzyme (ACE) inhibition, nitric oxide modulation, and vascular histology restoration. Cold extraction better preserves anthocyanins, which are strongly linked to antioxidant and cardioprotective outcomes, though the overall hypotensive impact is comparatively moderate. The findings suggest that hot extraction is preferable for therapeutic applications, while cold extraction may be suitable for functional beverages aimed at maximising anthocyanin content. Future research should optimise extraction conditions to balance phytochemical stability and pharmacological efficacy. Clinical trials are needed to validate dosage forms, long-term safety, and potential interactions with conventional antihypertensive drugs. This review evaluates how extraction methods shape the antihypertensive efficacy of Egyptian H. sabdariffa, guiding its integration into affordable cardiovascular care.
- Open Access
- Review
Comparative Review of Cold Maceration and Decoction Methods in Shaping the Antihypertensive Efficacy of Egyptian Hibiscus sabdariffa L.
- Gamal Moustafa Mahmoud Abdelfattah 1,*,
- Mohammad Hossein Hosseinzadeh 2,*,
- Tumpa Dey 3,
- Amirhossein Babaei 2,4,
- Ondrej Novak 1,
- Miroslav Strnad 1
Author Information
Received: 12 Dec 2025 | Revised: 18 Dec 2025 | Accepted: 24 Dec 2025 | Published: 29 Dec 2025
Abstract
Keywords
phytochemistry | pharmacology | functional foods | bioactive compounds | therapeutic applications
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