Hibiscus sabdariffa

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids II
Ordo: Malvales

Familia: Malvaceae
Subfamilia: Malvoideae
Tribus: Hibisceae
Genus: Hibiscus
Sectio: Hibiscus sect. Furcaria
Species: Hibiscus sabdariffa
Varietas: H. s. var. altissimus
Name

Hibiscus sabdariffa L.
References

Linnaeus, C. 1753. Species Plantarum. Tomus II: 695. Reference page.
USDA, ARS, Germplasm Resources Information Network. Hibiscus sabdariffa in the Germplasm Resources Information Network (GRIN), U.S. Department of Agriculture Agricultural Research Service. Accessed: 07-Oct-06.

Vernacular names
English: Roselle
suomi: Teehibiskus
한국어: 로젤
português: caruru-azedo, azedinha, quiabo-azedo, quiabo-róseo, quiabo-roxo, rosélia, vinagreira
ไทย: กระเจี๊ยบแดง, กระเจี๊ยบเปรี้ยว
Türkçe: Afrika bamyası

Roselle (Hibiscus sabdariffa) is a species of flowering plant in the genus Hibiscus that is native to Africa, most likely West Africa. In the 16th and early 17th centuries it was spread to the West Indies and Asia, respectively, where it has since become naturalized in many places.[1] The stems are used for the production of bast fibre and the dried cranberry tasting calyces are commonly steeped to make a popular infusion known as carcade.
Description

Roselle is an annual or perennial herb or woody-based subshrub, growing to 2–2.5 m (7–8 ft) tall. The leaves are deeply three- to five-lobed, 8–15 cm (3–6 in) long, arranged alternately on the stems.

The flowers are 8–10 cm (3–4 in) in diameter, white to pale yellow with a dark red spot at the base of each petal, and have a stout, conspicuous calyx at the base, 1–2 cm (0.39–0.79 in) wide, enlarging to 3–3.5 cm (1.2–1.4 in) and becoming fleshy and a deep crimson red as the fruit matures, which takes about six months.
Names
Roselle capsule
Roselle plant at Wave Hill
Asia

Roselle is known as karkadeh (كركديه) in Arabic, chin baung (ချဉ်ပေါင်) by the Burmese, luoshen hua (洛神花) in Chinese, kraceī́yb Thai: กระเจี๊ยบ (RTGS: krachiap) in Thai), ສົ້ມພໍດີ /sőm phɔː diː/ in Lao,[2] ស្លឹក​ជូរ /slɜk cuː/ សណ្តាន់​ទេស /sɑndan tẹːh/, ម្ជូរ​បារាំង /məcuː baraŋ/,[3] or ម្ជូរ​ព្រឹក /məcuː prɨk/ in Khmer, and cây quế mầu, cây bụp giấm, or cây bụt giấm in Vietnamese.
South-East Asia including Northeastern India and Mainland South Asia

Roselle is known as Pundi Palle / Pundi Soppu (ಪುಂಡಿ ಪಲ್ಯ / ಪುಂಡಿ ಸೊಪ್ಪು) in Kannada, Hoilfa (হইলফা) in Sylheti and Chukur (চুকুর), Amlamadhur (অম্লমধুর) in Bengali. Also known as Tengamora (টেঙামৰা) by various indigenous ethnic groups of Assam, dachang or datchang by Atongs, mwita among the Bodo(another native ethnicity of Assam), amile among Chakmas mostly in Chittagong, Gal•da among Garos, Hanserong among Karbi (an indigenous group of Asaam), among Lotha of Nagaland Hantserup, mathippuli (മത്തിപ്പുളി) and pulivenda (പുളിവെണ്ട) in Malayalam, ambadi (अंबाडी) in Maharashtra, okhreo among Maos, sillo sougri among Meitei, बेलचण्डा (belchanda) among Nepalese, and khata palanga (ଖଟାପାଳଙ୍ଗ) Jagatsinghpur and Cuttack districts and takabhendi (ଟକଭେଣ୍ଡି) in Odia in the Balasore district of Odisha, pulicha keerai (புளிச்சகீரை) in Tamil and gongura (గోంగూర) in Telugu. Anthur Sen(roselle red) or Lakher Anthur in Mizo, Hmiakhu Saipa(roselle red) or Matu Hmiakhu in Mara in Mizoram, India and Chin State, Myanmar.

It is called Ya Pung by the Marma people.

In the Chota Nagpur region, it is known as "Kudrum" or "Dhepa saag" in the Nagpuri/Sadri dialect. It is also known by different names in different languages of this region, like "Ipil jongor ", which means "star fruit" in the Mundari language.
Africa

Among the Yoruba in southwest Nigeria, Roselle is known as isapa, and yakuwa by the Hausa people of northern Nigeria who also call the seeds as gurguzu and the capsule cover as zoborodo or zobo.

Among the Tiv Tribe of Central Nigeria, the plant is called "Ashwe" while the capsule is referred to as "Agbende Ashwe". It is primarily consumed as a soup in three forms: The leaves are either cooked, or steamed and crushed on a grinding stone, in which form it is considered a delicacy due to its preservation of the characteristic 'tang' (slightly sour taste) of the leaves. The outer covering of the capsule (green variety) is also cooked as a soup which doesn't have the tang of the leaves. The red variant of the capsule are rarely (if ever) cooked, but instead boiled and the extract cooled and drank (like tea or soda when sugar is added). This form is known as "zobo" which is actually a borrowed name, just as this method of preparation is borrowed. Traditionally the red variant was used as a dye to color wood, and similar things.

Australia Roselle is known as the rosella or rosella fruit in Australia.
Latin America and the Caribbean

Roselle is known as saril or flor de Jamaica in Central America and sorrel in many parts of the English-speaking Caribbean, including Trinidad and Tobago, Jamaica and most of the islands in the West Indies.
Uses

In India, the plant is primarily cultivated for the production of bast fibre used in cordage, made from its stem.[4] The fibre may be used as a substitute for jute in making burlap.[5] Hibiscus, specifically roselle, has been used in folk medicine as a diuretic and mild laxative.[6]

The red calyces of the plant are increasingly exported to the United States and Europe, particularly Germany, where they are used as food colourings. It can be found in markets (as flowers or syrup) in places, such as France, where there are Senegalese immigrant communities.[7] The green leaves are used like a spicy version of spinach. They give flavour to the Senegalese fish and rice dish thieboudienne. Proper records are not kept, but the Senegalese government estimates national production and consumption at 700 t (770 short tons) per year.[8] In Myanmar their green leaves are the main ingredient in chin baung kyaw curry.[9]

Brazilians attribute stomachic, emollient, and resolutive properties to the bitter roots.[10]

Chutney

In Bihar and Jharkhand roselle is also known as "kudrum" in local language. The bright red petal of the fruit is used for chutney which is sweet and sour in taste.
Vegetable

In Satpuda Pradesh (near Maharashtra/Gujarat MP border), roselle is called khate fule by local tribal language. The khate fule leaves are mixed with green chillies, salt, some garlic to prepare a chutney and bhaji which is served with jowar (sorghum) or bajra (millet) made bakho (a flat bread). This is eaten by tribals as breakfast to start their day. A dry dish or sukhi bajji is prepared with khate fule leaves.[11]

In Andhra cuisine, roselle is called gongura and is extensively used. The leaves are steamed with lentils and cooked with dal. Another unique dish is prepared by mixing fried leaves with spices and made into a gongura pacchadi, the most famous dish of Andhra and Telangana often described as king of all Andhra foods. In Manipuri, it is called Sougri and it is used as a vegetables. It is generally cooked without oil by boiling with some other herbs and dried fish and is a favorite of the Manipuri people. Almost every household has this plant in their homes.

In Burmese cuisine, called chin baung ywet (lit. sour leaf), the roselle is widely used and considered affordable. It is perhaps the most widely eaten and popular vegetable in Myanmar.[12] The leaves are fried with garlic, dried or fresh prawns and green chili or cooked with fish. A light soup made from roselle leaves and dried prawn stock is also a popular dish.

Among the Paites tribe of the Manipur Hibiscus sabdariffa and Hibiscus cannabinus locally known as anthuk are cooked along with chicken, fish, crab or pork or any meat, and cooked as a soup as one of their traditional cuisines.[13] In the Garo Hills of Meghalaya, it is known as galda and is consumed boiled with pork, chicken or fish. After monsoon, the leaves are dried and crushed into powder, then stored for cooking during winter in a rice powder stew, known as galda gisi pura. In the Khasi Hills of Meghalaya, the plant is locally known as jajew, and the leaves are used in local cuisine, cooked with both dried and fresh fish. The Bodos and other indigenous Assamese communities of north east India cook its leaves with fish, shrimp or pork along with boiling it as vegetables which is much relished. Sometimes they add native lye called karwi or khar to bring down its tartness and add flavour.

In the Philippines, the leaves and flowers are used to add sourness to the chicken dish tinola (chicken stew).[14]

In Vietnam, the young leaves, stems and fruits are used for cooking soups with fish or eel.[15]

In Mali, the dried and ground leaves, also called djissima, are commonly used in Songhaï cuisine, in the regions of Timbuktu, Gao and their surroundings. It is the main ingredient in at least two dishes, one called djissima-gounday, where rice is slowly cooked in a broth containing the leaves and lamb, and the other dish is called djissima-mafé, where the leaves are cooked in a tomato sauce, also including lamb. Note that djissima-gounday is also considered an affordable dish.

In Namibia, it is called mutete, and it is consumed by people from the Kavango region in northeastern Namibia.

In the central African nations of Congo-Kinshasa, Congo-Brazzaville and Gabon the leaves are referred to as oseille, and are used puréed, or in a sauce, often with fish and/or aubergines.
Beverage
Main articles: Hibiscus tea and Roselle juice

Roselle, raw

Nutritional value per 100 g (3.5 oz)
Energy	205 kJ (49 kcal)
Carbohydrates	11.31 g
Fat	0.64 g
Protein	0.96 g
Vitamins	Quantity %DV†
Vitamin A equiv.	2% 14 μg
Thiamine (B1)	1% 0.011 mg
Riboflavin (B2)	2% 0.028 mg
Niacin (B3)	2% 0.31 mg
Vitamin C	14% 12 mg
Minerals	Quantity %DV†
Calcium	22% 215 mg
Iron	11% 1.48 mg
Magnesium	14% 51 mg
Phosphorus	5% 37 mg
Potassium	4% 208 mg
Sodium	0% 6 mg
Link to USDA Database entry
Units μg = micrograms • mg = milligrams IU = International units
†Percentages are roughly approximated using US recommendations for adults. Source: USDA FoodData Central

A roselle drink

In the Caribbean, a drink is made from the roselle fruit (the calyces with the seed pods removed). It is prepared by boiling fresh, frozen or dried roselle fruit in water for 8 to 10 minutes (or until the water turns red), then adding sugar. Bay leaves and cloves may also be added during boiling.[16] It is often served chilled. This is done in St. Vincent and the Grenadines, Trinidad and Tobago, Guyana, Antigua, Barbados, Belize, St. Lucia, Dominica, Grenada, Jamaica, the US Virgin Islands and St. Kitts and Nevis where the plant or fruit is called sorrel. The drink is one of several inexpensive beverages (aguas frescas) commonly consumed in Mexico and Central America; they are typically made from fresh fruits, juices or extracts. In Mexican restaurants in the US, the beverage is sometimes known simply as Jamaica (Spanish pronunciation: [xaˈmajka] HAH-MY-CAH). It is very popular in Trinidad and Tobago especially as a seasonal drink at Christmas where cinnamon, cloves and bay leaves are preferred to ginger.[17] It is also popular in Jamaica, usually flavored with rum.

In Ghana, Mali, Senegal, The Gambia, Burkina Faso, Ivory Coast and Benin calyces are used to prepare cold, sweet drinks popular in social events, often mixed with mint leaves, dissolved menthol candy, and/or fruit flavors.

The Middle Eastern and Sudanese "Karkade" (كركديه) is a cold drink made by soaking the dried Karkade calyces in cold water overnight in a refrigerator with sugar and some lemon or lime juice added. It is then consumed with or without ice cubes after the flowers have been strained.[18] In Lebanon, toasted pine nuts are sometimes added.

Roselle is used in Nigeria to make a refreshing drink known as Zobo and natural fruit juices of pineapple and watermelon are added. Ginger is also sometimes added to the refreshing drink.[19]

With the advent in the U.S. of interest in south-of-the-border cuisine, the calyces are sold in bags usually labeled "flor de Jamaica" and have long been available in health food stores in the U.S. for making tea. In addition to being a popular homemade drink, Jarritos, a popular brand of Mexican soft drinks, makes a flor de Jamaica flavored carbonated beverage. Imported Jarritos can be readily found in the U.S.

In the US, a beverage known as hibiscus cooler is made from the tea, a sweetener, and sometimes juice of apple, grape or lemon. The beverage is sold by some juice companies.[20]

In the UK, the dried calyces and ready-made sorrel syrup are widely and cheaply available in Caribbean and Asian grocers. The fresh calyces are imported mainly during December and January to make Christmas and New Year infusions, which are often made into cocktails with rum. They are very perishable, rapidly developing fungal rot, and need to be used soon after purchase — unlike the dried product, which has a long shelf-life.

In Africa, especially the Sahel, roselle is commonly used to make a sugary herbal tea that is sold on the street. The dried flowers can be found in every market. Roselle tea is quite common in Italy where it spread during the first decades of the 20th century as a typical product of the Italian colonies. The Carib Brewery, a Trinidad and Tobago brewery, produces a 'Shandy Sorrel' in which the tea is combined with beer.

In Thailand, roselle is generally drunk as a cool drink,[21] and it can be made into a wine.

Hibiscus flowers are commonly found in commercial herbal teas, especially teas advertised as berry-flavoured, as they give a bright red colouring to the drink.

Rosella flowers are sold as wild hibiscus flowers in syrup in Australia as a gourmet product. Recipes include filling them with goats cheese; serving them on baguette slices baked with brie; and placing one plus a little syrup in a champagne flute before adding the champagne — the bubbles cause the flower to open.

In Dodoma Tanzania the Roselle juice is brewed to make Roselle wine famous by the name of choya.
Jam and preserves

In Nigeria, rosella jam has been made since colonial times and is still sold regularly at community fetes and charity stalls. It is similar in flavour to plum jam, although more acidic. It differs from other jams in that the pectin is obtained from boiling the interior buds of the rosella flowers. It is thus possible to make rosella jam with nothing but rosella buds and sugar.[22]

In Burma, the buds of the roselle are made into 'preserved fruits' or jams. Depending on the method and the preference, the seeds are removed or included. The jams, made from roselle buds and sugar, are red and tangy.

In India, Roselle is commonly made into a type of pickle.

"Sorrel jelly" is manufactured in Trinidad.

Rosella jam is made in Queensland, Australia as a home-made or speciality product sold at fetes and other community events.[23]
Herbal medicine (high blood pressure)

Although a 2010 meta-analysis using 14 databases and hand searching journals conducted by the Cochrane hypertension group concluded "No studies were identified that met the inclusion criteria"[24][needs update] a more recent meta-survey (2015) in the Journal of Hypertension suggests a typical reduction in blood pressure of around 7.5/3.5 units (systolic/diastolic).[25]
Production
Harvesting roselle planted on bris (sandy) soils in Rhu Tapai, Terengganu (September 2002)

China and Thailand are the largest producers and control much of the world supply.[26] The world's best roselle comes from Sudan and Nigeria, b. Mexico, Egypt, Senegal, Tanzania, Mali and Jamaica are also important suppliers but production is mostly used domestically.[27]

In the Indian subcontinent (especially in the Ganges Delta region), roselle is cultivated for vegetable fibres. Roselle is called meśta (or meshta, the ś indicating an sh sound) in the region. Most of its fibres are locally consumed. However, the fibre (as well as cuttings or butts) from the roselle plant has great demand in natural fibre using industries.

Roselle is a relatively new crop to create an industry in Malaysia. It was introduced in the early 1990s and its commercial planting was first promoted in 1993 by the Department of Agriculture in Terengganu. The planted acreage was 12.8 ha (30 acres) in 1993 and steadily increased to peak at 506 ha (1,000 acres) by 2000. The planted area is now less than 150 ha (400 acres) annually, planted with two main varieties. Terengganu state used to be the first and the largest producer, but now the production has spread more to other states. Despite the dwindling hectarage over the past decade or so, roselle is becoming increasingly known to the general population as an important pro-health drink. To a small extent, the calyces are also processed into sweet pickle, jelly and jam.

Crop research

In the initial years, limited research work was conducted by University Malaya and Malaysian Agricultural Research and Development Institute (MARDI). Research work at Universiti Kebangsaan Malaysia (UKM) was initiated in 1999. In many respects, the amount of research work is considered[by whom?] meagre in supporting a growing roselle industry in Malaysia.

Hibiscus Acid has been isolated from its calyx which is done by the Institute for Integrated Programmes and Research In Basic Sciences, Mahatma Gandhi University Kerala. Recently, gallic and protocatechuic acids were identified using solvent extraction, column chromatographic fractionation, and nuclear magnetic resonance (NMR) spectroscopy as the antidiabetic and antihypertensive principles of the calyxes.[28]
Crop genetic resources and improvement

Genetic variation is important for plant breeders to increase crop productivity. Being an introduced species in Malaysia, there is a very limited number of germplasm accessions available for breeding.

UKM maintains a working germplasm collection and conducts agronomic research and crop improvement.
Mutation breeding

Conventional hybridization is difficult to carry out in roselle due to its cleistogamous nature of reproduction. Because of this, a mutation breeding programme was initiated to generate new genetic variability.[29] The use of induced mutations for its improvement was initiated in 1999 in cooperation with MINT (now called Malaysian Nuclear Agency) and has produced some promising breeding lines. Roselle is a tetraploid species; thus, segregating populations require longer time to achieve fixation as compared to diploid species. In April 2009, UKM launched three new varieties named UKMR-1, UKMR-2 and UKMR-3. These new varieties were developed using Arab as the parent variety in a mutation breeding programme which started in 2006.
Natural outcrossing under local conditions

A study was conducted to estimate the amount of outcrossing under local conditions in Malaysia. It was found that outcrossing occurred at a very low rate of about 0.02%. However, this rate is much lower in comparison to estimates of natural cross-pollination of between 0.20% and 0.68% as reported in Jamaica.

Phytochemicals

The Hibiscus leaves are a good source of polyphenolic compounds. The major identified compounds include neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeoylshikimic acid and flavonoid compounds such as quercetin, kaempferol and their derivatives.[30] The flowers are rich in anthocyanins, as well as protocatechuic acid. The dried calyces contain the flavonoids gossypetin, hibiscetine and sabdaretine. The major pigment is not daphniphylline.[31] Small amounts of myrtillin (delphinidin 3-monoglucoside), chrysanthenin (cyanidin 3-monoglucoside), and delphinidin are present. Roselle seeds are a good source of lipid-soluble antioxidants, particularly gamma-tocopherol.[32]

Gallery

A popular roselle variety planted in Malaysia: Terengganu. Roselle fruits are harvested fresh, and their calyces are made into a drink rich in vitamin C and anthocyanins.

Two varieties are planted in Malaysia — left Terengganu or UMKL-1, right Arab. The varieties produce about 8 t/ha (3.6 short tons/acre) of fresh fruits or 4 t/ha (1.8 short tons/acre) of fresh calyces. On the average, variety Arab yields more and has a higher calyx to capsule ratio.

Dried roselle calyces can be obtained in two ways. One way is to harvest the fruits fresh, decore them, and then dry the calyces; the other is to leave the fruits to dry on the plants to some extent, harvest the dried fruits, dry them further if necessary, and then separate the calyces from the capsules

Roselle calyces can be processed into sweet pickle. This is usually produced as a by-product of juice production. However, quality sweet pickle may require a special production process.

Variation in flower colour of roselle (a tetraploid species)

Calyx (a collective term for sepals of a flower); Epicalyx (a collective term for structures found on, below, or close to the true calyx, also called false calyx). Some varieties show pronounced epicalyx structures, such as found in variety Arab (plural calyces).

Decoring — removal of a seed capsule from the fruit using a simple hand-held gadget to obtain its calyx

Some breeding lines developed from the mutation breeding programme at UKM.

Footnotes

"Roselle - plant". Encyclopedia Britannica.
Reinhorn, Marc, Dictionnaire laotien-français, Paris, CNRS, 1970, p. 688.
Pauline Dy Phon, វចនានុក្រមរុក្ខជាតិប្រើប្រាស់ក្នុងប្រទេសកម្ពុជា, Dictionnaire des Plantes utilisées au Cambodge, Dictionary of Plants used in Cambodia, ភ្នំពេញ Phnom Penh, បោះពុម្ពលើកទី ១, រោងពុម្ព ហ ធីម អូឡាំពិក (រក្សាសិទ្ធិ៖ អ្នកគ្រូ ឌី ផុន) គ.ស. ២០០០, ទំព័រ ៣៤៣-៣៤៤, 1st edition: 2000, Imprimerie Olympic Hor Thim (© Pauline Dy Phon), 1er tirage: 2000, Imprimerie Olympic Hor Thim, pp. 343-344; Mathieu LETI, HUL Sovanmoly, Jean-Gabriel FOUCHÉ, CHENG Sun Kaing & Bruno DAVID, Flore photographique du Cambodge, Toulouse, Éditions Privat, 2013, p. 360.
Standley, Paul C.; Blake, S. F. (1923). "Trees and Shrubs of Mexico (Oxalidaceae-Turneraceae)". Contributions from the United States National Herbarium. Washington, D.C.: Department of Botany, Smithsonian Institution. 23 (3): 779. JSTOR 23492504.
Duke, James A. (7 January 1998). "Hibiscus sabdariffa L." Handbook of Energy Crops. Center for New Crops & Plant Products, Purdue University.
"Hibiscus". Drugs.com. 21 May 2021.
Peter, K.V (2007). Underutilized and Underexploited Horticultural Crops. Vol. 2. Kerala, India: New India Publishing Agency. p. 204. ISBN 978-8189422691.
Peter 2007, p. 205
Sula, Mike (4 September 2013). "How to eat hibiscus like the Burmese". Chicago Reader.
"Roselle". hort.purdue.edu.
https://vanitascorner.com/khate-fule/}
Hansen, Barbara (1993-10-07). "Uncommon Herbs : In a Burmese Garden". Los Angeles Times.
"Kelsa ~ Hau Za Cin :: ZOMI DAILY". www.zomidaily.org. 3 January 2015.
"Chicken Tinola Recipe". Panlasang Pinoy. Retrieved 2021-09-09.
Tanaka, Yoshitaka; Van Ke, Nguyen (2007). Edible Wild Plants of Vietnam: The Bountiful Garden. Thailand: Orchid Press. p. 91. ISBN 978-9745240896.
"Sorrel Juice Is Good for You". Sweet TnT Magazine. 8 November 2017. Retrieved 16 September 2020.
"Sorrel Drink". Simply Trini Cooking. 16 December 2008.
butteredup (29 February 2012). "Karkadeh: A Sweet Hibiscus Tea".
"Zobo Drink a.k.a. Zoborodo".
"Hibiscus Cooler". R.W. Knudsen Family. Retrieved 2018-06-04.
Mai_25759. "น้ำกระเจี๊ยบแดง มาฝากของเย็นเป็นเครื่องดื่มกันต่อค่ะ". Mthai Picpost.
"Jam of the tropics: growing and using Rosella |". Retrieved 2021-09-09.
ezimerchant Professional. "Rosella Jam 120g". Bushtuckershop.com. Retrieved 2014-03-29.
Ngamjarus C, Pattanittum P, Somboonporn C (2010). "Roselle for hypertension in adults". Cochrane Database of Systematic Reviews. 2010 (1): CD007894. doi:10.1002/14651858.CD007894.pub2. PMC 7182310. PMID 20091658. CD007894.
Serban C, Sahebkar A, Ursoniu S, Andrica F, Banach M (2015). "Effect of sour tea (Hibiscus sabdariffa L.) on arterial hypertension: a systematic review and meta-analysis of randomized controlled trials". Journal of Hypertension. 33 (6): 1119–27. doi:10.1097/HJH.0000000000000585. PMID 25875025. S2CID 19042199.
"HIBISCUS Post-harvest Operations page 4" (PDF).
"fao.org". Retrieved 2007-08-25.
Alegbe, Emmanuel Ohifueme; Teralı, Kerem; Olofinsan, Kolawole Ayodapo; Surgun, Serdar; Ogbaga, Chukwuma Collins; Ajiboye, Taofeek Olakunle (23 May 2019). "Antidiabetic activity‐guided isolation of gallic and protocatechuic acids from Hibiscus sabdariffa calyxes". Journal of Food Biochemistry. 43 (7): e12927. doi:10.1111/jfbc.12927. PMID 31353728. S2CID 182039601.
"FNCA 2005".
Zhen J, Villani TS, Guo Y, Qi Y, Chin K, Pan MH, Ho CT, Simon JE, Wu Q (2016). "Phytochemistry, antioxidant capacity, total phenolic content and anti-inflammatory activity of Hibiscus sabdariffa leaves". Food Chemistry. 190: 673–680. doi:10.1016/j.foodchem.2015.06.006. PMID 26213025.
Bassey, Rosemary B. (28 August 2021). "The stain extracted from roselle is not daphniphylline". The Biological Stain Commission.

Mohamed R, Fernández J, Pineda M, Aguilar M (2007). "Roselle (Hibiscus sabdariffa) seed oil is a rich source of gamma-tocopherol". J Food Sci. 72 (3): S207–11. doi:10.1111/j.1750-3841.2007.00285.x. PMID 17995816.

Further reading
Chau, J. W.; Jin, M. W.; Wea, L. L.; Chia, Y. C.; Fen, P. C.; Tsui, H. T. (2000). "Protective effect of Hibiscus anthocyanins against tert-butyl hydroperoxide-induced hepatic toxicity in rats". Food and Chemical Toxicology. 38 (5): 411–416. doi:10.1016/S0278-6915(00)00011-9. PMID 10762726.
Mohamad, O.; Mohd. Nazir, B.; Abdul Rahman, M.; Herman, S. (December 2002). "Roselle: A new crop in Malaysia". Buletin Persatuan Genetik Malaysia. 8 (1): 12–13.
Mohamad, O.; Mohd. Nazir, B.; Azhar, M.; Gandhi, R.; Shamsudin, S.; Arbayana, A.; Mohammad Feroz, K.; Liew, S.K.; Sam, C.W.; Nooreliza, C.E.; Herman, S. (2002). "Roselle improvement through conventional and mutation breeding". Proceedings of INC 2002. International Nuclear Conference 2002: Global Trends and Perspectives, Seminar I: Agriculture and Biosciences: 23–41. RN:34030224, TRN: MY0301988030224.
Mohamad, O.; Ramadan, G.; Herman, S.; Halimaton Saadiah, O.; Noor Baiti, A. A.; Ahmad Bachtiar, B.; Aminah, A.; Mamot, S.; Jalifah, A.L. (2008). "A promising mutant line for roselle industry in Malaysia". FAO Plant Breeding News. 195.
Pau, L. T.; Salmah, Y.; Suhaila, M. (2002). "Antioxidative properties of roselle (Hibiscus sabdariffa L.) in linoleic acid model system". Nutrition & Food Science. 32 (1): 17–20. doi:10.1108/00346650210413951.
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