RESEARCH OF Rosella
In Indonesia, studies of test components and nutrients in the antioxidant activity of Rosella petals had been investigated by Ir Didah Nurfaridah, 2005. In these studies, she (as the staff of the faculty in the Department of Food Science and Technology Faculty of Agricultural Technology, Bogor Agricultural University) found that levels of antioxidants contained in the dried petals Rosella much higher than the cat whiskers plant and Knop flower. Active substances most responsible for Rosella flower petals are: gossypetin, antosianin, and hibiscin glucoside. Antosianin is a natural pigment that gives red color on the Rosella petals, and is an antioxidant.
"High levels of antioxidants in the Rosella eyelids can hamper free radicals. Some chronic diseases found at this time many are caused by excessive free radicals. Among of them are kidney damage, diabetes, coronary heart disease, to cancer, "said Didah.
Comparison of antioxidants levels which have antosianin can be seen in two types of Rosella planted in Darwin's gardens at Cisarua. Although derived from a single species, Sudanese Rosella thick blackish-red, while Taiwan Rosella blood red. Sudanese Rosella it more acidic and more concentrated so that the dried petals can be used up to 2-3 times brewed. Differ from Taiwan Rosella that can only be used once brewed.
"The more intense red color on the petals Rosella, it will be more acidic and there are more antosianin content. Thus, antioxidant content also increased, "said Didah.
Unfortunately, the levels of antioxidants in the petals Rosella are reduced when dried by the heating process (baked in the oven). Levels of potent compounds contained in the petals Rosella is at the highest levels when consumed in fresh form.
Anticancer and Antihypertensive
Among the many functions, Rosella seeded as anticancer herbs and hypertension. This is in accordance with preclinical trials conducted by Yun-Ching Chang, a researcher from the Institute of Biochemistry and Biotechnology, Chung Shan Medical University in Taiwan. Yun-Ching Chang found that the natural pigment from the dried petals Rosella proven effective in both inhibiting and lethal cancer cells HL-60 (blood cancer or leukemia). These pigments also play a role in the process of apoptosis (suicide) of cancer cells.
Meanwhile, Maureen Williams, ND, a naturopathic physician from Bastyr University in Seattle, United States, has conducted a study of 70 people with mild levels of disease-to-moderate hypertension whose healthy condition and did not do any treatment since one month before
the study tested. At random, some people were asked to consume as many as Rosella tea and a half liter before breakfast every day. Some are taking 25 mg of antihypertensive drugs. After four weeks, diastolic blood pressure was reduced by ten points to 79% of people who consume tea Rosella and 84% in people who take antihypertensive medications.
Had never reported serious side effects due to consumption of other Rosella petal heart beating. But Peter Hardwick of the journal Australian Food Plants Study Group Newsletter said that there is another species called the Native Rosella Rosella (Hibiscus heterophyllus) that can cause kidney damage if consumed. Fresh flowers like Rosella (Hibiscus sabdariffa). Therefore, be careful, do not let the wrong choice.