Ultrasonic-Assisted Extraction and In-Vitro Antioxidant Activity of Polysaccharide from Hibiscus Leaf

In this study, methanolic extracts of Hibiscus rosa-sinensis showed higher phenolic and flavonoid content, as well as greater concentrations of gallic acid and quercetin, than aqueous extracts, despite the latter yielding more extract, highlighting the effectiveness of methanol for extracting bioactive phytochemicals.

This study found that red-flowered cultivars of Hibiscus rosa-sinensis displayed the highest antioxidant activity, phenolic, and flavonoid content compared to other colored cultivars.

This study compared the antioxidant and antidiabetic activities of Hibiscus rosa-sinensis leaf extract and Eclipta alba bark extract, finding that Hibiscus rosa-sinensis exhibited greater antidiabetic activity, whereas Eclipta alba demonstrated stronger antioxidant activity.

The researchers reported that a hydroalcoholic extract of Hibiscus Rosa Sinensis flowers was more effective than glibenclamide in reducing blood sugar levels in alloxan-induced diabetic rabbits, and demonstrated superior antioxidative and lipid-lowering effects, suggesting potential as an alternative antidiabetic treatment.

This study found that the crude extract of Hibiscus rosa-sinensis leaves, whether irradiated or not, showed significant antioxidant activity without causing toxicity in rats, suggesting gamma radiation may enhance its therapeutic properties.