The popular zobo drink made from the calyx (flower part) of roselle (Hibiscus sabdariffa) has been successfully used in traditional medicine to treat various diseases such as cough, hypertension, stomach disorders, loss of appetite, upper respiratory congestion, nerve and heart disorders and menstrual difficulties. But recent studies suggest that although it could be used to reduce the risk of kidney damage in diabetics, high doses could lead to kidney damage. CHUKWUMA MUANYA writes.
CAN drinking high doses of the popular zobo drink lead to kidney damage? Results of a recent study suggest that aqueous extract of Hibiscus sabdariffa (HSE) has no harmful effect on the liver but when consumed in high doses could be harmful to the kidney. “Further research aimed at identifying the chemical composition and potential toxic agent(s) in HS is recommended,” the researchers wrote.
Commonly called zobo or roselle in Nigeria, Hibiscus sabdariffa belongs to the plant family malvaceae.
The study titled: “Toxicilogical effects of aqueous extract of Hibiscus Sabdariffa on the liver and kidney,” was published in Journal of College of Medicine.
The aim of the study is to show the effect of graded doses of aqueous extract of HS on major excretory organs (liver and kidney) of albino Wistar rats. This may be helpful in determining the safety or otherwise of its consumption at different concentrations.
The researchers wrote: “There were no significant changes in the histology of the liver throughout the period of HS administration in all the groups. However, there were significant histological changes in the kidney, which were more pronounced at higher doses (80 and 160mg/kg). There was shrinkage of glomerular tuft, increase in urinary pole, increase in size of tubular lumen and tubular damage. These effects were more marked as the duration of administration of the extract progressed with greatest effect observed at 12th week.”
Another study found that Hibiscus sabdariffa might help treat kidney stones via uricosuric activity. The study titled: “Uricosuric effect of Roselle (Hibiscus sabdariffa) in normal and renal-stone former subjects,” was published in Journal of Ethnopharmacology.
Uricosuric agents are used to lower the uric acid level in the blood and to prevent the formation of uric acid crystals in the joints and kidneys. These drugs are often used to treat gout, a disease in which uric acid crystals deposit in joints and cause pain. By decreasing plasma uric acid levels, these drugs decrease the deposition of crystals in joints, eventually decreasing inflammation and thereby reducing the pain of gout.
Researchers from Thailand conducted a study with nine subjects with no history of kidney stones and nine with a history of kidney stones. A cup of tea made from 1.5 grams of dry roselle was provided to subjects twice daily (morning and evening) for 15 days.
After taking the tea, both groups showed increases in oxalate and citrate. In the non-kidney stone group, increases in uric acid excretion and clearance were observed. In the patients with kidney stones, both uric acid excretion and clearance were significantly increased.
The study authors concluded that roselle has a uricosuric effect and they suggested that the chemical constituents exerting this effect should be identified.
Also, researchers have shown that aqueous (water) extracts of HSE is capable of reducing lipid peroxidation, increasing catalase and glutathione activities significantly in diabetic kidney, and decreasing the plasma levels of triglyceride, low-density lipoprotein (LDL) and increasing high-density lipoprotein (HDL) value.
Lipid peroxidation is a well-defined mechanism of cellular damage in both animals and plants that occurs in vivo during aging and in certain disease states.
Catalase is an antioxidant enzyme found in living organisms that changes hydrogen peroxide to water and oxygen. Hydrogen peroxide is formed as a toxic waste product of metabolism. It must be quickly converted into other, less dangerous, chemicals. To manage this problem, the enzyme catalase is frequently used to rapidly catalyse the decomposition of hydrogen peroxide into harmless oxygen and water.
Glutathione is an antioxidant compound found in living animal and plant tissue. Glutathione is the major endogenous antioxidant produced by the cell. Glutathione participates directly in the neutralization of free radicals, reactive oxygen compounds, and maintains exogenous antioxidants such as vitamins C and E in their reduced (active) forms. In addition, through direct conjugation, glutathione plays a role in the detoxification of many xenobiotics (foreign compounds) both organic and inorganic. Glutathione is an essential component of the human immune response.
Triglycerides are a type of lipid found in blood. When food is consumed, calories are released by the oxidation of food. The calories, which the body does not exhaust, are converted into energy resources called triglycerides which are stored in the fat cells of the body and are used to supply energy when required. Under the action of certain hormones these triglycerides are broken into simpler, absorbable forms of fatty acids to liberate energy.
LDL is “bad” cholesterol, while HDL is “good” cholesterol.
According to the study published in Evidence-Based Complementary and Alternative Medicine, HSE, in histological examination, improves hyperglycemia-caused osmotic diuresis in renal proximal convoluted
Hyperglycemia or Hyperglycæmia, or high blood sugar, is a condition in which an excessive amount of glucose circulates in the blood plasma.
Osmotic diuresis is increased urination caused by the presence of certain substances in the small tubes of the kidneys.
The proximal convoluted tubule is the most proximal segment of the renal tubular portion of the nephron. It is responsible for the reabsorption of glucose, amino acids, various ions and water.
The study also reveals that up-regulation of Akt/Bad/14-3-3? and NF-?B-mediated transcription might be involved.
The researchers concluded: “In conclusion, our results show that HSE possesses the potential effects to ameliorate diabetic nephropathy via improving oxidative status and regulating Akt/Bad/14-3-3? signaling.”
The study is titled: “Aqueous extract from Hibiscus sabdariffa linnaeus ameliorate diabetic nephropathy via regulating oxidative status and Akt/Bad/14-3-3? in an experimental animal model.”
Several studies point out that oxidative stress maybe a major culprit in diabetic nephropathy. Diabetic nephropathy is kidney disease or damage that occurs in people with diabetes. HSE has been demonstrated as having beneficial effects on anti-oxidation and lipid-lowering in experimental studies.
This study investigated the effects of Hibiscus sabdariffa L. on diabetic nephropathy in streptozotocin induced type 1 diabetic rats.
Diabetic mellitus (DM) is a consequence of chronic metabolic aberrations including hyperlipidemia. High glucose facilitating the glycolysis and adenosine triphosphate generation would cause huge reactive oxygen species (ROS) production. Under physiological circumstances, ROS involve some signaling molecules and follow defense mechanisms such as phagocytosis, neutrophil function and shear-stress induced vasorelaxation.
However, excessive oxidative stress could damage proteins, lipids, and DNA and eliminate anti-oxidative enzymes or molecules. Ujihara et al. observed that oxidized LDL level was significantly higher in diabetic patients with macroalbuminuria. They suggested that oxidized-LDL might play an important role in diabetic nephropathy.
Experimentally, the oxidative level of LDL can be determined by detecting lipid peroxidation. Antioxidant defense mechanisms include free radical scavengers and enzyme systems, such as superoxide dismutase (SOD), glutathione peroxidase (GSH) and catalase (CAT). Previous studies showed that these anti-oxidative molecules were reduced in diabetes.
In addition to the devastating damage effect on macromolecules, oxidative stress can be involved in cellular signal transduction including Akt signaling pathway. Akt is a principal mediator of biological functions of insulin in glucose metabolism. Phosphorylated Akt can regulate apoptosis via activating Bad to associate with 14-3-3? protein and also to activate nuclear factor-kappa B (NF-?B) to regulate transcription.
Recent studies showed the importance of phosphoinositide 3-kinases (PI3-K) and Akt signaling pathway in diabetic nephropathy including regulation of renal mesangial hypertrophy and renal tubular cells proteolysis. It has been well known that hyperglycemia and insulin could modulate Akt activity in diabetic renal tissue. However, the results are not compatible. Furthermore, the correlation between oxidative stress and Akt signaling in diabetic renal tissues has not been well clarified.
A wide variety of natural products have been found to possess capacity to control metabolic problems and oxidative stress in diabetes. Hibiscus sabdariffa Linnaeus is usually used as a beverage. The constituents in the flowers of Hibiscus species are polyphenolic acids, flavonoids, and anthocyanins.
Previous studies found that HSE possessed anti-oxidative characteristics and had anti-atherosclerotic effects. Recent pharmacological studies also showed that HSE significantly reduced blood pressure in humans and in experimental animals.
The heat is here again and coming with the season is the need to increase one’s fluid intake. Although many drinks are available to quench people’s thirst, one healthy drink worth patronising is the zobo drink made from the red calyx of hibiscus.
The Hibiscus plant is of different varieties, many of which have been used medicinally. For instance, Hibiscus sabdariffa, what many refer to as zobo, roselle or Isapa pupa has been used as a folk medicine in the treatment of a variety of ailments, including hypertension, obesity, high cholesterol level and diabetes.
For instance, some Nigerian researchers have confirmed that this popular drink, Zobo, prepared with roselle (fresh calyx of Hibiscus sabdariffa as main ingredient) scent leaf (Ocimum gratissimum), garlic (Allium sativum) and ginger (Zingiber officinarium) could be effectively used to treat diarrhoea and pneumonia.
Hibiscus sabdariffa is commonly called Roselle in English. It is widely grown and commonly used as pot herb or soup in the northern part of Nigeria. In Hausa, the plant is locally called Yakuwa, the seed as Isontea while the fresh calyx is referred to as Soboroto. The Yoruba call the leaves Amukan and the flowers Ishapa.
Commonly called scent leaf, Ocimum gratissimum is known as Efinrin ajase in Yoruba, Ebavbokho in Bini, Aai doya ta gida in Hausa, Nchuanwu in Igbo. The leaves are used locally for soup. It is also used to treat cases of stomach upset and diarrhoea.
Garlic (Allium sativum) is called ayuu in Igbo and ayu in Yoruba. The bulb is used for fevers, coughs, constipation, asthma, nervous disorders, hypertension, ulcers and skin diseases. It contains chemical substances that stop the growth of bacteria and kill fungi as well as act as worm expellers.
Aside garlic bulbs being used for seasoning and flavouring agent, garlic also serves as an effective remedy for hypertension, muscular pain and sore eyes. It is digestive and helps to prevent the formation of gas in the gastrointestinal tract as well as to facilitate the expulsion of gas, thereby combating flatulence.
Commonly called ginger, it is called jinja in Ibibio, jinja in Igbo and aje or atale in Yoruba. The rhizome is used to treat toothache, congested nostrils, cough, colds, influenza and flu, asthma, stomach problems, rheumatism, piles, hepatitis and liver problems. It is also extensively used as an herbal remedy to control or prevent nausea, vomiting, and motion sickness; a cold remedy, an aid to digestion; and a remedy for intestinal gas.
What is more, incorporating zobo drinking into daily diets, scientists in the February 2010 issue of the Journal of Nutrition found, supports lower blood pressure. A study which involved participants, aged 30 to 70, who consumed three 240 milliliter servings of brewed hibiscus tea per day for six weeks, showed lower blood pressure readings at the end of the study period than at the beginning.
Hibiscus tea reduced both systolic pressure — the upper number of the blood pressure ratio, which represents the pressure in the blood vessels when the heart contracts — and diastolic — the lower number, which represents the pressure in the blood vessels during relaxation of the heart.
In addition, hibiscus tea helps to prevent kidney stones, according to a study reported in the May 2008 issue of the Journal of Ethnopharmacology. The study showed that hibiscus tea improved the kidneys’ ability to filter out the waste product — uric acid and oxalic acid, both of which can form kidney stones if they accumulate to excessively high levels.
Ironically, diabetics with high blood pressure who equally drink zobo stand to experience its blood pressure-lowering benefits, as corroborated by another study published in the January 2009 issue of the Journal of Human Hypertension, that found drinking zobo drinks made
Journal of Food Technology
Year: 2007 | Volume: 5 | Issue: 3 | Page No.: 225-228
Effects of Some Preservation Techniques on the Quality and Storage Stability of Zobo Drink (A Nigerian, Non Alcoholic Beverage from Hibiscus sabdariffa)
Abstract:
The microbial and nutritional quality of laboratory produced Zobo drink (obtained from aqueous extract of dried calyces of Hibiscus sabdariffa) was investigated. The samples were subjected to pasteurization (at 70°C for 25 min) alone and with sodium benzoate (0.1%) in combination with pasteurization. Storage stability at room temperature (28±2°C) of aseptically packaged sachets of the beverage in 50 mL was assessed using physico-chemical parameters (loss in vitamin C content, changes in pH and titratable acidity) and microbial changes. The proximate composition of Zobo drink was 88.88% water, 0.046% protein, 0.15% fat, 0.61% crude fibre, 0.21% ash and 10.64% carbohydrate. These values did not change significantly (p>0.05) with respect to treatment methods nor storage time. However, vitamin C content of the beverage 1,105.88 mg 100 mL in the control samples decreased by 53.4 and 61.46% due to pasteurization and sodium-benzoate plus pasteurization respectively. The total plate count of the unpreserved beverage (control) decreased from 1.2×105 cfu mL 1 to 5.0×103 and 1.0×103 cfu mL 1 when subjected to pasteurization and to a combination of sodium benzoate plus pasteurization, respectively. The two methods were both effective in eliminating E. coli and Staplyloccus aureus in the beverage. Bacillus sp., Lactobacillus sp., Saccharomyces, cerevisiae, Mucor sp. and Aspergillus niger were found in association with progressive spoilage [detected in acid- and alcohol production] in the beverage. The shelf life of the beverage on storage was 4, 14 and above 40 days for the control, pasteurized only and sodium-benzoate plus pasteurized samples, respectively.
Roselle, raw
Nutrition facts
Scientifical name: Hibiscus sabdariffa
Food category: Fruits and Fruit Juices
Refuse name: Seed pods and stem
Refuse (percent): 39%
Usual serving weight: 57.0
Nutrient: Average amount in 100g of product: Min. amount.: Max. amount:
Water 86.580 g - -
Energy 49.000 kcal - -
Energy 205.000 kj - -
Protein 0.960 g - -
Total lipid (fat) 0.640 g - -
Ash 0.510 g - -
Carbohydrate, by difference 11.310 g - -
Calcium, Ca 215.000 mg - -
Iron, Fe 1.480 mg - -
Magnesium, Mg 51.000 mg - -
Phosphorus, P 37.000 mg - -
Potassium, K 208.000 mg - -
Sodium, Na 6.000 mg - -
Vitamin C, total ascorbic acid 12.000 mg - -
Thiamin 0.011 mg - -
Riboflavin 0.028 mg - -
Niacin 0.310 mg - -
Vitamin B-12 - - -
Vitamin A, IU 287.000 IU - -
Vitamin A, RAE 14.000 mcg_RAE - -
Retinol - - -
Cholesterol - - -
For more information or to schedule an appointment,for more about permanent lip augmentation gurgaon and cosmetic surgery.
ReplyDelete