ABSTRACT
The most popular form of consuming herbs in Sri Lanka nowadays is as herbal porridge or ‘kola kanda’ as it is known in the Sinhala language. This is a rice-based gruel added to ground-up leaves of herbs and is usually eaten on an empty stomach. The practice appears to have originated from the Buddhist priests in the country, who consumed herbal porridge as a breakfast item following a fasting period after their lunch of the previous day. Herbs are generally consumed in this manner for restoration and rejuvenation of vigor and, according to ancient beliefs, they supposedly provide long life, beauty, health, wellness, power, insight, and intellect. There are many herbs that have been added since ancient times into the preparation of these porridges. Most of these herbs are creepers or small plants, a valuable characteristic given the traditional method of grinding them on a grindstone. In modern times, however, the grinding of the herbs to obtain their juicy extract is performed using kitchen blenders in many Sri Lankan households. Some of the herbal porridges have been sold in instant sachet-form and added to boiling water to obtain the broth. Overall, consuming porridge is a timeless practice among Sri Lankans and is a healthy habit to be cultivated given the beneficial effects of the herbs used to prepare the porridge.
Centella. asiatica
Centella. asiatica is a highly researched herb and has appeared in many of the traditional medicinal systems across the world as an agent for enhancing memory power. In Sri Lanka, the herb is called ‘gotu kola’ and is consumed in salad form as well as with rice porridge. C. asiatica is native to Sri Lanka, northern Australia, and Malaysia and flourishes well in humid areas in tropical countries. Despite recognizing its medicinal properties and benefits of consumption for health and wellness purposes, no serious efforts have been devoted till now for planning and organizing the commercial propagation and cultivation of C. asiatica. Asiaticoside, madecasosside (brahminoside), Asiatic acid, and madecassic acid are the most important bioactive constituents isolated from C. asiatica to date. Several flavonoid derivatives such as quercetin, kaempferol, patuletin, rutin, apigenin, castilliferol, castillicetin, and myricetin have also been reported in the whole plant. Madecassol®, Centellase®, or Blastoestimulina® are some of the commercial tablets that are formulated from an C. asiatica extract. Additionally, the extract has been incorporated into several cosmetic products. Given the significant amount of scientific evidence, C. asiatica remains a very important traditional medicinal herb in Sri Lanka and its acceptance and attention in the consumer market of the country continues to expand.
Murraya koenigii (L.) Spreng
Murraya koenigii is an important traditional medicinal herb as well as a seasoning agent used in Sri Lanka and the rest of the Indian sub-continent. It is known as ‘karapincha’ in Sinhala or curry leaves in English. Other than its food and medicinal value, M. koenigii serves as an important component in various other products such as cosmetics, aromatherapy products, bath oils, and incense. The herbal porridge made from M. koenigii is a popular breakfast item in Sri Lanka while it is also available in packaged form in supermarkets as an herbal tea. In the traditional medicinal system of the country, the leaf extract has been used for snake and insect bites; improving appetite; preventing liver diseases, worm infections, skin infections, diabetes, and weight loss; as an emetic and improving digestion; and to help prevent untimely growth of grey hairs. M. koenigii is an herb that has undergone extensive characterization of its chemical constituents and the bioactive properties have been well elucidated in in vitro and in vivo studies. The major bioactive compounds in M. koenigii are mahanimbine, murrayanine, murrayazoline, isomahanine, koenoline, mukolidine, mukoline, mukonal, and girinimbine. These compounds along with various solvent extracts of the plant’s parts possess antioxidant, anti-cancer, analgesic, anti-helminthic, and blood purifying effects. Despite extensive use and consumption of M. koenigii, no side effects have been recorded to date, indicating a good safety record of the plant.
Alternanthera sessilis
Alternanthera sessilis is an aquatic plant that is known as ‘mukunuwenna’ in the Sri Lankan vernacular language of Sinhala. It was a plant that was originally mis-identified with A. philoxeroides in Melbourne, Australia, where the latter was considered as an invasive species by the Department of Primary Industries in Australia. The increased demand for A. sessilis plants especially as food and medicine has resulted in their rapid depletion from primary habitats. Thus, tissue culture techniques are being explored at present for clonal multiplication and in vitro conservation. A. sessilis has been traditionally used in Sri Lanka for chronic headaches, night blindness, eye infections, asthma, catarrh, urinary infections, fatigue, rabies, snake bites, and spider bites. It has been used in the traditional medicinal systems of India, Bangladesh, Ghana, and Nigeria for various ailments as well. The antioxidant, anti-inflammatory, anti-cancer, wound-healing, analgesic, and anti-hyperglycemic effects of various solvent extracts of the plant’s parts have been established in in vitro and in vivo studies. The presence of wound healing-associated phytocompounds such as hexadecanoic acid have been found in the plant extract, along with methoxy-bis (cyclopentadiene), 5,10-dihexyl- 5,10-dihydroindolo[3,2-b]indole-2,7-dicarbaldehyde, and 1,2-bis[3,4-dimethoxy benzyl]-1,2-bis (methoxymethyl) ethane, which possesses anti-asthmatic effects.
Gymnema sylvestre
Gymnema sylvestre R. Br. is a perennial woody vine that grows in the tropics and has been used for several therapeutic purposes in many of the traditional medicinal systems, although mostly as an anti-diabetic. Several commercial, over-the-counter herbal products are now available: Bioshape®, Diaxinol®, Body Slatto Tea®, Gymnema®, Gymnema Diet®, and Sugar Off®. Due to commercial exploitation, G. sylvestre appears to be disappearing fast and is threatened with extinction. In the traditional medicinal system of Sri Lanka, together with treating diabetes, G. sylvestre leaves and extracts are used also to treat eye diseases, allergies, constipation, cough, dental caries, obesity, stomach ailments, and viral infections. In the traditional medicinal preparations, the plant is typically consumed with mashed fenugreek seeds and neem leaves for the treatment of diabetes, as well as with artichoke flowers for weight loss. The leaves of G. sylvestre contain triterpene saponins belonging to the classes of oleanane and dammarane. The major secondary metabolites in G. sylvestre include a group of nine closely related acidic glycosides, gymnemic acids A–D, which are found in all parts of the plant. Extracts of the plant possess anti-sweet, anti-diabetic, antioxidant, anti-cancer, and antimicrobial effects. However, very little effort has been made to verify the efficacy of G. sylvestre against disease conditions in animal models and clinical trials. Also, the metabolic profiling of G. sylvestre has not been adequately carried out although there are some metabolomics and genomics studies.
Aerva lanata
Aerva lanata is a perennial weed, which is commonly found across the Indian sub-continent. Given its abundance and ample availability, almost all the traditional medicinal systems of this region, including Sri Lanka, have some documentation of its use for preventing and curing ailments. Specifically, this herb has been used in Sri Lanka for the treatment of urinary infections and bladder stones. This herb is known as ‘Pol palā’ in Sinhala (a vernacular language in Sri Lanka). There are differences in the method of preparation and administration of the herb between the medicinal systems of the Indian sub-continent. In Sri Lanka, the herb is consumed by adding to rice gruel or taken as an herbal tea. It possesses nephrolithiasis, urolithiasis, antioxidant, anti-diabetic, anti-cancer, anti-microbial, and anti-HIV properties. A comprehensive phytochemical screening of the bioactive compounds has not been carried out on the plant. However, tannins, saponins, terpenoids, flavonoids, alkaloids, triterpenoids, protein, anthroquinones, polyphenol, and glycosides in the methanol and aqueous extracts have been identified. Also, the compound (2S.3R) 3-(3-hydroxy-3methyl pent-4-en-1-yl)-2,5,5,8a tetramethyldecahydronaphthalene-2-ol is one natural product responsible for the nephrolithiasis effect. A. lanata has the potential to be developed into a medication for the treatment of bladder stones – given its traditional use and growing scientific evidence.
Atalantia ceylanica
Atalantia ceylanica belongs to the family Rutaceae and is a citrus herb. The plant is considered as an under-utilized crop in modern times. It is known as ‘yaki nāran’ in Sinhala and ‘pey kurundu’ in Tamil. It is used by the local population of Sri Lanka primarily for the ailments of catarrh, asthma, rheumatism, skin diseases and irritations, respiratory disorders and to alleviate bee and wasp stings. The presence of imperatorin and oxypeucedanin has been reported in the leaf extract of A. ceylanica. Both these compounds have shown bioactive effects such as anti-cancer and hepatoprotective activity. Additionally, the compounds 2,4,5-trimethoxybenzaldehyde, 1,5-dihydroxy-3-methoxy-10-methyl-9(10H)-acridone, 11-hydroxynoracronycine and pyranoflavone carpochromene and 3,12-dihydro-6,11-dihydroxy-3,3,12-trimethylpyrano[2,3-c]acridin-7-one and its 5-(3-methylbut-2-enyl) derivative have been isolated from the leaf extract, although their therapeutic properties have not been demonstrated to date. Overall, despite only a limited amount of scientific studies, A. ceylanica remains an important herb in the Sri Lankan traditional medicinal pharmacopoeia and is used nowadays for various medicinal purposes.
Sesbania grandiflora
Sesbania grandiflora is an important herbal medicine used in many of the traditional medicinal systems of South Asia. In Sri Lanka, it is a commonly consumed leafy vegetable either in salad or in porridge form, although the latter method of consumption may not be all that popular due to the plant’s astringent and bitter taste. All parts of the plant have been used for various ailments. In the traditional medicinal system of Sri Lanka S. grandiflora has been used for the treatment of diarrhea, snake bite, malaria, smallpox, fever, scabies, ulcer, and stomach disorders. Isovestitol, medicarpin, and sativan, along with betulinic acid, have been isolated from the leaves of S. grandiflora, while two new 2-arylbenzofurans – sesbagrandiflorain A and B – have been isolated from the stem bark. Isovestitol, medicarpin, sativan, and betulinic acid possess potent anti-tuberculosis activity in vitro. Additionally, various parts of the plant have been scientifically investigated for their antioxidant, anti-cancer, anti-diabetic, anti-microbial, anti-helminthic, and cytotoxicity effects. There are also several miscellaneous uses of S. grandiflora: a potential pulp wood and for extracting heavy metals by rhizo-filtration. Mass-production of S. grandiflora through biotechnological approaches is underway, since the plant is of value as a source of income to many of the tribal people of South Asia.
Vernonia cinerea (L.) Less
V. cinerea is known as ‘monarakudumbiya’ in Sri Lanka. It is a weed found in the country and is commonly consumed in porridge form, added to rice gruel, although the plant extract may also be administered orally to patients depending on the ailment. The plant has been used in several traditional medicinal systems in Asia, where in Sri Lanka, it has been used for the treatment of conjunctivitis, rheumatism, appendicitis, encephalitis, skin diseases, prolonged fever, cough, and cold. The bioactive compounds present in V. cinerea extracts have been identified: vernolide-A, B, C, and D as well as lupeol, 12-oleanen-3-ol-3β-acetate, stigmasterol, and β-sitosterol have been isolated and tested for their bioactivity in various in vitro assays. The extract of the herb possesses antioxidant, anti-cancer, anti-malarial, and anti-microbial effects. Interestingly, V. cinerea has been investigated to help cessation of smoking cigarettes, and several studies were conducted in Thailand owing to its traditional use in that region for this specific use, and the results have been promising.
