Senna siamea .is a medium-sized shrub growing 10- to 12 meters high, occasionally reaching 20 meters. Trunk is short, the crown dense and rounded, later becoming irregular and spreading. Leaves are alternate, 15 to 30 centimeters long, pinnately compound with 6 to 14 leaflets on short stalks, each ending in a tiny bristle. Flowers are bright yellow, large, up to 60 centimeters long, upright, with pyramid-shaped panicles. Fruit are flat, with indehiscent pod, 5 to 30 centimeters long, constricted between seeds, each pod containing about 20 seeds. Seeds are bean-shaped, greenish brown, 8 to 15 millimeters long.
- Native to South and Southeast Asia.
- Phytochemical screening of aqueous and ethanol extracts yielded alkaloid, anthraquinone, saponin, tannin, phenol, steroid,flavonoid, terpenoid, and glycosides. (see study below) (4)
- Main constituents reported are chromone (anhydrobarakol), chromone alkaloids (barakol, cassiarin A-B), anthraquinone (chrysophanol, emodin), bianthraquinones (cassiamin A-B), flavonoids and phenolic compounds.
- Proximate analysis of leaves yielded 7.43% moisture content, 20.62% ash, 3.00% lipid, 21.88% protein, 13.00% crude fiber, and 34.07% carbohydrate content. Phytochemical screening yielded high amounts of terpenoids, tannins, and volatile oils; moderate amounts of alkaloids and cardiac glycosides; low presence of saponins, steroids, flavonoids, and general glycosides.
Elemental analysis yielded appreciable amounts of iron, magnesium, and calcium, at 11.03% 10.83%, and 3.08%, respectively.
- Phytochemical screening of leaves yielded: alkaloids++, saponins+, tannins+++, steroids+, flavonoids+, terpenoids+++, volatile oils+++ cardiac glycosides++, glycosides (general)+, with absence of anthraquinones and phylobatannins. (8)
- Phytochemical screening of methanol extract of stem bark yielded alkaloid, flavonoids, cardiac glycosides, tannins, saponins, and terpenoids. (see study below) (9)
- Chromatographic study of various extracts of leaves yielded nine compounds:
stigmasterol (1), lupeol acetate (2), 2-methoxy-4'-hydroxy-3',5'-diprenylchalcone (3), chrysin (4), chrysophanol (5), kaempferol (6), quercetin (7), 2-methyl anthraquinone (8), 3,7,-dimethoxy-3', 4'-methylenedioxy-flavone (9). (15)
-Study of methanolic extract of stems isolated a new allelochemical (a), characterized as 3,7-dihydroxy-5,3',4'-trimethoxyflavone-3-O-β-D-xylopyranosyl-7-O-α-L-rhamnopyranosyl(1→4)-O-α-L-arabinopyranoside, along with two known compounds, scutellarin 7-O-ß-D-glucopyranoside (B) and luteolin (c). (see study below) (18)
-Ethanol extract of leaves yielded yielded reducing sugar, tannins, saponins, steroids, flavonoids, gums, alkaloids and glycosides. (see study below) (21)
- Proximate analysis of flowers yielded valuable nutrients (g/100g): crude protein 25.49 ± 0.014, crude fiber 15.63 ± o.04, ash 7.10 ± 0.03, crude fat 9.68 ± 0.04, moisture content 5.54 ± 0.03, and carbohydrate 36.56 ± 0.01. Mineral analysis yielded calcium 726.00, magnesium 726.00, manganese 938.00, copper 64.00, zinc 30.00,iron 30.00, cadmium 8.00, and lead 16.00. Fatty acid profile showed the oil contained higher proportion of unsaturated fatty acid (51.06%) than saturated fatty acid (39.75%). Of the saturated fatty acids, palmitic acid (31.92%) was mot abundant, while linoleic acid (20.86%) and linolenic acid (16.93%) were most abundant unsaturated fatty acids. (see study below) (27)
- Study for secondary metabolites yielded tannins +++, saponin ++, terpenoids +++., phytosterols +++, resins ++, with absence of alkaloids.
- Anthraquinones found in the leaves of S. siamea are rhein, cassiamin, physcion, chrysophanic acid, and sennosides ( Gritsanapan, 1983; Nualkaew, 1999). (see study below)
- Study of two fractions of ethyl acetate and ethanol wood extracts yielded five compounds: resveratrol, piceatannol, dihydropiceatannol, chrysophanol, and emodin. (see study below) (33)
- Study of methanol and hexane extracts of leaves yielded phenols, tannins, anthraquinones, alkaloid, and flavonoids. GC-MS study yielded saponins, triterpenoids (lupeol, α-amyrin), sesquiterpene (octadecane), diterpenes (eicosane), esters of phthalic acids (diethyl phthalate), squalene, α-tocopherol (as fat soluble vitamin E), and hexadecanoic and butyl ester. (see study below) (35)
- Shown to have antimicrobial, antimalarial, antidiabetic, anticancer, diuretic, hypotensive, antioxidant, laxative, anti-inflammatory, analgesic, antipyretic, anxioytic, antidepressant and sedative activities.
- Studies suggest antibacterial, analgesic, anti-inflammatory, antidiabetic, laxative properties.
Leaves, stems, roots, seeds, flowers.
- In Thailand, young leaves, tender pods, seeds, and flowers are edible. A popular Thai dish is kaeng khilek. (11)
- Leaves, tender pods and seeds are edible, but must be boiled and the water discarded.
- In the Burmese full moon day of Tazaungmon, buds are picked and used in a soup or to prepare a salad called mezali phu thokke. (11)
- Used to treat hypertension, malaria, and diabetes.
- Leaves, stems, roots, seeds, and flowers used for treatment of malaria.
- In Thailand, leaves traditionally used as a sleep aid.
- In Burkina Faso, decoction of fresh and dried leaves, stem bark, and flowers used to treat malaria and liver disorders.
Decoction of stem bark drunk for diabetes.(5)
In Cote d'Ivoire, decoction of leaves drunk for cough, stomach pains, and malaria. In Uganda, leaves are chewed and swallowed to treat abdominal pain. In India leaf decoction with honey drunk for anemia and fever. (5)
- in Laos, a dish called "chi om leck," a mixture made from decoction of fresh and dried leaves
and pork bones crushed to a paste, taken as a vegetable with euphorizing and sedative effects. (5)
- In Thailand, dried leaves in capsule formulation taken as laxative or sleeping pill. (5)
- In China and Pakistan,, decoction of leaves and stems mixture used as aperitif, antirheumatic, and for swelling. In the Congo, decoction of leaves and stems used for periodic fever and malaria.
- In Nigeria, used for the treatment of syphilis, herpes, swine fever, typhoid fever, jaundice, abdominal pain, menstrual pain.
Among the Iqbos, used for its anti-gonorrheal and purgative properties. Fresh leaves used to repel or kill insects i.e., termites, bed bugs, and mosquitoes. (8) (see study below) (15)
- In Cameroon, leaves are used as antimalarial; fruits used to treat intestinal worms and to prevent convulsions in children.
- Agroforestry: Used as shade tree, hedgerows, or live fence.
- Tanning: All parts of the plant can be used for tanning. Concentration varies slightly with plant parts: 17% leaves, 9% barks, and 7% in fruits. (25)
- Wood: Heartwood is brownish-black with paler streaks. Wood is hard and durable, resistant to termites. Used for joinery, cabinetry, in-laying, decorative pieces, poles, posts, and beams. (25)
- Fire use:Wood makes good fuel, although somewhat smoky when burning. Energy value is 22,400 kJ/kg. Wood also produces good quality charcoal. (25)
• Sub-Chronic Toxicity / Stem Bark: Study evaluated the sub-chronic toxicity of an aqueous stem bark extract in healthy male Wistar rats. Results showed an oral LD50 greater than 5000 mg/kbw. There were not signs of toxicity or death during the test periods. The extract produced significant (p<0.05) increase in body weight from the second to the seventh week. (3)
• Antibacterial / Leaves: Study evaluated the phytoconstituents and antibacterial activity of S. siamea aqueous and ethanol leaf extracts against some pathogenic bacteria viz., K. pneumonia, S. typhi, Shigella spp, E. coli, and P. aeruginosa. Highest antibacterial activity was seen with the ethanol extract with average zone of inhibition of 14.12 ± 1.51 mm among the isolates. E. coli showed highest susceptibility. (see constituents above) (4)
• Acute Toxicity / Leaves: At higher doses, diverse extracts of C. siamea showed acute toxicity in various animal models. In a rat model, leaf ethanol extracts caused mortality with intraperitoneal LD50 of 9600 mg/kg within 24 hours. Root aqueous extract at 8000 mg/kg po in 24 hours showed hyper-sensitivity reactions, cytotoxicity, and increases in aggressiveness in rats. In chronic toxicity studies, aqueous extracts at 2000 mg/kg po for 2 weeks caused hepatic and renal cell destruction in albino rats. (5)
• Protection Against Diabetes-Induced Insulin Resistance and Endothelial Dysfunction / Leaves:Study evaluated the effect of oral leaf extract on glucose, insulin homeostasis, liver damage, and endothelial dysfunction in experimental model of T2 diabetic leptin-deficient ob-ob mice. Results showed remarkable attenuation of T2DM features on glucose, hepatic inflammation, insulin resistance, endothelial function and vascular oxidative stress. Results suggest therapeutic potential of C. siamea in correcting metabolic and vascular alterations associated with T2DM. (6)
• Antimicrobial / Leaves: Study evaluated the antimicrobial activity of various extracts and fractions of S. siamea leaf on selected microorganisms i.e., E. coli, S. aureus, K. pneumonia, P. aeruginosa, and S. typhi using agar well diffusion method. The extracts inhibited the growth of microorganims with zones of inhibition ranging from 2 to 18 mm. The ethanol extract showed highest ZOI on S. typhi. Activity was attributed to alkaloids, saponins, tannins, glycosides, phenolic, and flavonoids. (7)
• Analgesic / Anti-Inflammatory / Stem Bark: Study evaluated the phytochemicals, analgesic and anti-inflammatory activities of methanol extract of S. siamea stem bark. LD50 of the extract was ≥5000 mg/kg. On analgesic testing, the extract caused inhibition on writhing response induced by acetic acid in a dose dependent manner, and increased time of tail flicking in a dose dependent manner. On anti-inflammatory testing, the extract significantly (p<0.05) inhibited inflammation induced by egg albumin in rats paw. (9)
• Barakol / Leaves and Flowers: Barakol, a major substance from S. siamea Study characterized the content of barakol in various plant parts. HPLC (high performance liquid chromatography). Average barakol in mature leaves and young flowers was 0.300 and 0.279% w/w, respectively. Boiling water extracts yielded the highest barakol content in three herbal recipes (0.077, 0.123, and 0.085% w/w). (11)
• Chronic Toxicity / 6-Month Study / Leaves: Toxicity study evaluated a six-month use of powdered leaves containing 0.17% barakol in Wistar rats. Levels of bilirubin in animals receiving doses of 200 and 2,000 mg/kbw per day were significantly highest than controls The higher the dose taken, the more severe the degree f hepatic damage observed, especially in male rats Results suggest male rats were more susceptible to the hepatotoxic effects than female rats. Reduction of hepatic damage in the recovery group suggested the hepatotoxic effect was reversible when the drug was stopped for only 14 days. Results suggest long-term consumption of leaf could produce dose-dependent hepatotoxic effects in rats even at therapeutic doses. Hence, caution is advised wen the leaf is used as sleep aid for a long period of time and the use discontinued when periodic liver function tests suggest drug-induced hepatitis. (12)
• Antiplasmodial Activity / Leaves: Study evaluated the antiplasmodial activity of hydroalcoholic leaves extract of A. bipindensis and Senna siamea using Plasmodium berghei and investigated the acute and sub-acute toxicity of leaves extract in a rodent model. Study showed leaves extract showed significant antiplasmodial activity with parasite reduction of ≈ 50%. No mortality was observed at tested doses. Results suggest benefit in the treatment of malaria with no significant risks to human health. (13)
• Antihyperglycemic / Renal Protective / Leaves: Study evaluated aqueous extract of leaves for effect on hyperglycemia in experimental diabetes in alloxan-induced diabetic rats. BUN and creatinine were measured as biomarkers of kidney function. Results suggest leaves can provide a beneficial effect on hyperglycemia and protect against kidney dysfunctions in diabetes.(14)
• Antibacterial / Leaves: Study of various extracts of leaves yielded nine compounds. The isolated compounds were screened for antimicrobial activity. A methanolic extract showed considerable activity against Bacillus pumilis. There was no activity against fungi tested.(see constituents above) (15)
• Hepatotoxic Effect / Leaves: Study evaluated the effect of a methanol extract of leaves on liver functions in Wistar albino rats receiving doses of 100, 200, and 499 mg/kbw. While AST and ALP showed no significant changes, ALT activity increased significantly (p<0.05) during the 3rd and 4th weeks, along with significant bilirubin increase. Histological changes showed degenerative changes. Results suggest prolonged ingestion of high concentration of methanol extract could to toxic to hepatocytes. (16)
• Larvicidal Effect / Leaves: Study evaluated the larvicidal properties of C. siamea extract against fourth instar larvae of Culex quinquefasciatus, a carrier of mosquito-borne diseases. LC50s at 24, 48, 72, and 96 h were 394.29, 350.24, 319.17 and 272.42 ppm, respectively. The LC50 and LC90 values gradually decreased with exposure time. A dose dependent mortality was observed. (17)
• Larvicidal Effect / Leaves: Study of methanolic extract of stems isolated a new allelochemical (a), along with two known compounds, scutellarin 7-O-ß-D-glucopyranoside (B) and luteolin (c). The compounds were evaluated for antioxidant activity. Compound A exhibited higher radical scavenging activity by DPPH assay. (see constituents above) (18)
• Anxiolytic / Barakol: Study evaluated the behavioral effects of Cassia siamea and barakol,its active chemical using elevated plus-maze. Barakol at 10 mg/kg intraperitoneally significantly increased all behavioral parameters in a manner similar to diazepam. Results indicate barakol has anxioytic properties similar to diazepam, and unlike diazepam, also increases exploratory and locomotor behavior, in measures of number of rears and total arm entries. (19)
• Study n Toxic Effects on Liver and Kidney / Hypoglycemic: Study evaluated the toxic effects of an aqueous extract on liver and kidney of male albino rats. Results showed a drastic reduction (p<0.05) in the activities of ALP, AST and ALT in the liver with a corresponding increase in serum levels, indicating mild liver damage, which returned to normal when the extract was stopped. Increase of AST and ALT in the kidney and serum might be due to activation of enzyme synthesis in renal cells. Study also revealed hypoglycemic properties of the extract. Study suggests prolonged usage of the aqueous extract may lead to cell destruction. (20)
• Cytotoxicity Potential by Brine Shrimp Lethality / Leaves: Study evaluated the phytochemical properties and cytotoxicity potential for ethanolic extract of Senna siamea leaves. Phytochemical screening yielded reducing sugar, tannins, saponins, steroids, flavonoids, gums, alkaloids and glycosides. Cytotoxicty testing by brine shrimp lethality assay showed moderate cytotoxic activity with LC50 of 68.633 µg/ml. Results suggest a potential source of cytotoxic compounds. (21)
• Antiplasmodial Activity / Pure Compounds: Study evaluated the antiplasmodial activity of extracts and fractions of C. siamea stem bark on schizonts of chloroquine-resistant Plasmodium falcifarum. Fc, Fe, and molecules P2, P18, P27 were the most active. The antiplasmodial active principles were not cytotoxic and belonged to groups of alkaloids and triterpenoids. Results justify the use of the plant against malaria in traditional medicine in the Congo. (22)
• Antidiabetic / Leaves: Study evaluated various extracts of C. siamea leaves for antidiabetic activity in alloxan-induced diabetic model. An ethyl acetate extract of leaves produced significant (p<0.001) reduction in plasma glucose levels when compared to ethanol and hexane extracts. (23)
• Barakol / Quantitative Analysis: TLC densitometric method evaluated the barakol content in Senna siamea leaf and flower extracts and compared barakol content in mature leaves young leaves, and young flowers.
Barakol was extracted as pure lemon-yellow crystals from young leaves with 0.1% yield. Barakol content in young leaves, mature leaves and young flowers were 1.67, 0.78 and 1.43% dry weight, respectively. (25)
• Cassiarins A and B / Novel Antiplasmodial Alkaloids / Leaves: Study isolated two novel alkaloids, cassiarins A (1) and B (2) from the leaves of C. siamea. Cassiarin A (1) exhibited potent antiplasmodial activity. (26)
• Flowers / Nutritional Composition / Concerns: Flowers were evaluated for proximate composition, mineral elements and fatty acid profile. Results showed the flowers are good sources of essential nutrients, but the detection of cadmium and lead calls for caution, and advises that the flowers be properly processed before consumption. (see constituents above) (27)
• Laxative Anthraquinone / Effect of Boiling / Leaves: Study evaluated the contents of total anthraquinone glycosides in Senna siamea, which are active laxative form, and total anthraquinones in fresh young leaves, boiled leaves, and boiled filtrates. Anthraquinone compounds are known for their laxative properties. Results showed the process of preparation of khi lek curry by boiling S. siamea young leaves twice with water reduced total anthraquinone glycosides content more than 75%. It confirms the traditional use of khi lek curry as a very mild laxative drug. (see constituents above) (30)
• Laxative Anthraquinone / Effect of Boiling / Leaves: Study evaluated the anti-pseudomonal activities of aqueous, chloroform, and ethanolic extracts of Senna siamea leaves. All extracts were active at high concentration levels of 500 and 1000 µg/disc suggesting dose-dependent activity. The aqueous extract was most active with ZOI of 19 mm and 30 mm. Ciprofloxacin was used as positive control. The antipseudomonal potential of the leaves may be due to phytoconstituents in the leaves such as tannins, saponins, and steroids. (31)
• Effect on CD4+ Levels and Antioxidant Profile in HIV/AIDS Patients: Because of therapeutic failures caused by resistance and supply disruptions, there have been searches for other antiretroviral agents from natural sources. In the Northern Cameroon region, Azadirachta indica and Senna siamea decoction has been traditionally attributed antiretroviral value. In this study of HIV positive patients, patients treated by ARTs + decoction showed an increase in CD4+ level from 328 ± 106 to 752 ± 140. Results suggest the decoction of AI and SS stimulates the production of CD$+ and is not toxic, and can potentially reduce the toxicity caused by ARTs intake. (32)
• Anti-Insulin Resistance Effect: Senna siamea has been used as an antidiabetic drug such antiquity. Study evaluated the molecular mechanism regarding insulin resistance. On preliminary investigation, ethyl acetate and ethanol extracts showed potent effects against insulin resistance on zebrafish larvae. All the five isolated compounds from the fractions showed anti-insulin resistance effects on zebrafish larvae. Resveratrol, piceatannnol, and dihydropiceatannol also demonstrated inhibitory effects against
α-glucosidase. Chrysophanol and emodin inhibited PTP1B activity, while resveratrol showed DPP-IV inhibition effect via molecular docking. Results suggest S. siamea components has effects against insulin resistance and present potential therapeutic options in the treatment of diabetes. (33)
• Antimicrobial / Peripherally Acting Analgesic Activity / Leaves: Study evaluated the analgesic and antimicrobial potential of S. siamea leaves. The acetic acid induced writhing test at dose of 500 mg/kg exhibited significant (p<0.001) inhibition of writhing reflex by 81.98% while standard drug diclofenac showed inhibition of 85.85% at dose of 25 mg/kbw. The extract showed activity against Pseudomonas aeruginosa at concentration of 500 µg/disc with zone of inhibition of 10 mm. (34)
• Antimalarial / Antiplasmodial / Leaves: Study of leaf extracts showed dose dependent suppression of parasite growth, with the methanolic extract showing less antimalarial potency (IC50= 3.74 µg/ml) compared to the hexane extract (IC50=5.349 µg/ml. (see constituents above) (35)
• Larvicidal / Aedes aegypti Larvae / Leaves: Study evaluated the mosquito larvicidal efficacy of Cassia siamea leaf aqueous extract by determining the median lethal concentration, LC50, within 24,48,72, and 96 hours. Histopathological effects such as separation of epithelial cells from the basement membrane, elongation and protrusion into its lumen, microvilli disruption, appearance of vesicles and cytoplasm masses showed C. siamea as a bioinsecticide in the midgut of A. aegypti larvae. Results suggest larvicidal property with potential for use as an indigenous mosquito control agent, an alternative to chemical mosquito larvicides. (36)
- Capsule and powder formulations in the cybermarket.