Roselle, scientifically known as Hibiscus sabdariffa, is a shrub belonging to the Malvaceae family. In chinese community, it is commonly called as Luo Shen Hua (洛神花). Due to its sourness, it is known as sour tea in some countries. In English-speaking countries, it is called Red Sorrel. Sorrel drink can be prepared by boiling dried calyces of the plant in water for 8-10 minutes, then adding sugar and usually served chilled. This plant originated from Africa but is now widely cultivated in tropical and subtropical regions of the world particularly in India and Southeast Asia.
Roselle Hibiscus has its flower (calyx), seeds and leaves that can be used in pharmaceutical and food industries. It has been used as a therapeutic plant for centuries. Traditionally, it treats toothaches, urinary tract infections, colds, and even hangovers.
The flower of the Roselle Hibiscus has the brilliant red color and unique flavor making it a valuable food product. Roselle Hibiscus is often compared to cranberry for its nutritional values, but this plant is widely cultivated in Malaysia and therefore more people should understand for its nutritional values since it is easily available.
Roselle Hibiscus extract is extracted using dry calyx and it has intense color and flavor so making it suitable to be stored and easy to be diluted when comes to consumption. Besides, it can serve as a colorant in many cuisines including bakery because the color is stable upon high heating temperature. This extract contains natural vitamins and minerals such as calcium and potassium that quenches thirst and revitalises the body. The drink reportedly possesses anti-hypertensive, diuretic and mild laxative properties.
Most importantly, Roselle Hibiscus contains abundant amounts of natural antioxidants such as vitamin C and anthocyanins that bring color and health benefits. The color of anthocyanin has color hue of red to violet in the pH range of 2-4. Therefore, it is very suitable to be applied in acidic foods. Roselle Hibiscus has ascorbic acid but the predominant organic acids are oxalic acid and succinic acid.
Anthocyanins found in the calyces of H. sabdariffa contain
Anthocyanins are great antioxidants that help to protect the body from diseases because they neutralize the free radicals present in body tissues and cells. This can prevent aging.
In vitro study on antioxidant activity of Roselle Hibiscus extract
|Groups||• Roselle extract • BHA • α-tocopherol|
|Parameters analysed||• TPC • Diene-conjugation formation • TBA|
|Function||• The calyx extract of HS is a potential source of natural antioxidants with the presence of anthocyanins, ascorbic acid, flavonoids and phenolic acid. • Anthocyanins are able to scavenge radicals by hydrogen donation, to assist in radical stabilization, to protect RBCs against ROS attacks, and to increase RBC integrity and function.|
|Visible benefits||• Roselle extract had stronger antioxidant properties than BHA or α-tocopherol • 0.2 mg/mL extract inhibited more than 85% of diene-conjugated compounds. • The total phenolic compound of the extract was 2.9 mg/g calyx (GAE equivalent).|
Boost Immune System
Roselle Hibiscus is rich in ascorbic acid (vitamin C), which can boost and stimulate the activity of immune system. This helps to prevent cold and flu.
In vivo study on effect of Roselle Hibiscus extract on immune system
|Subject||Male rats (n=80)|
|Duration of study||5 hour|
|Dosage||200, 400, 800 mg/kg|
|Groups||• Treatment group • Control: aspirin|
|Parameters analysed||Body temperature|
|Function||• Roselle can strengthen body immune system to lower down fever caused by infection. • It has phytochemicals that can reduce the inflammatory cells and activate the immunomodulatory activity in thymus and spleen.|
|Visible benefits||• Both the ethanol and aqueous extract of HS calyces (800mg/kg) decreased the fever induced by yeast in rats. • The extract could attenuate the formation of cytokines such as interleukins, interferons.|
In vitro and in vivo study on effect of Roselle extract on weight
|Groups||• Treatment group • Control: ascorbic acid|
|Parameters analysed||Free radical scavenging activity|
|Function||The extract of HS can prevent starch digestion and prevent building of fat cells.|
|Visible benefits||Organic acids inhibit the α-amylase which reduce starch breakdown and α-glucosidase to reduce glucose absorption.|
In vitro and in vivo study on anticancer activity of Roselle Hibiscus extract
|Subject||Breast cancer (MCF-7 and MDA-MB-231) Ovarian cancer (Caov-3) Cervical cancer (HeLa)|
|Duration of study||72 hour|
|Dosage||0.002, 0.02, 0.2, 2, 20%|
|Groups||• Treatment group • Positive control • Negative control|
|Parameters analysed||• MTT cell proliferation • DPPH free radical scavenging activity|
|Function||• Anthocyanins and polyphenols from Roselle extract can induce apoptosis on various cancer cells without causing death to healthy cells. • They can protect against cancer before it happens such as drug-induced leukemia.|
|Visible benefits||• Hibiscus anthocyanins (HAs) exerted anti-proliferative effect against various cancer cells. • The HAs from calyces inhibited cell proliferation and possessed cytotoxic activity possibly due to apoptosis induction properties of anthocyanins via ROS-mediated mitochondrial dysfunction pathway.|