Syzygium cumini, also known as jambul, jambolan, jamblang, or jamun, is an evergreen tropical tree in the flowering plant family Myrtaceae. Syzygium cumini is native to the Indian Subcontinent and adjoining regions of Southeast Asia. The species ranges across India, Bangladesh, Pakistan, Nepal, Sri Lanka, Malaysia, the Philippines, and Indonesia.
The name of the fruit is sometimes mistranslated as blackberry, which is a different fruit in an unrelated family. In southern Asia, the tree is venerated by Buddhists, and it is commonly planted near Hindu temples because it is considered sacred to Lord Krishna.
The compounds in the tree, including the leaves, fruit, seeds and bark, include: 1
- Ellagic acid
The fruit contains:
- Citric acid
- Mallic acid
- Gallic acid
- Cyanidin diglycoside
The seeds of the fruit contain:
- Glycoside jambolin
The plant has been considered an anti-diabetic medicinal remedy throughout the Indian and Asian populations. During the last four decades, numerous folk medicinal reports on the anti-diabetic effects of this plant have been cited in the literature.
The Table below lists the various folk medicine uses of Syzygium cumini:
|Ethnic group used and their origin||Plant part used, mode of preparation, administration and ailments treated||References|
|Local people in southern Brazil||Either infusions or decoctions of leaves of jambolan in water at an average concentration of 2.5 g/L and drank it in place of water at a mean daily intake of about 1 liter are used in the treatment of diabetes.|||
|Lakher and Pawi in North east India||Infusion of fruit or mixture of powdered bark and fruit is given orally to treat diabetes.|||
|Juice obtained from the seeds is applied externally on sores and ulcers.|
|Powdered seeds are mixed with sugar are given orally 2–3 times daily in the treatment of dysentery.|
|The juice of leaves is given orally as antidote in opium poisoning and in centipede bite.|
|The juice of ripe fruits is stored for 3 days and then is given orally for gastric problems.|
|The juice obtained from the bark is given orally for the treatment of women with a history of repeated abortion.|
|Local informants in Maharastra, India||Fruit and stem bark are used in the treatment of diabetes, dysentery, increases appetite and to relieve from headache|||
|Nepalese, Lepchas and Bhutias in northeast India||Decoction of stem bark is taken orally three times a day for 2–3 weeks to treat diabetes|||
|Native amerindians and Quilombolas in North eastern Brazil||Leaves are used in the treatment of diabetes and renal problems.|||
|Kani tribals in Southern India||Two teaspoon of juice extracted from the leaf is mixed with honey or cow’s milk and taken orally taken twice a day after food for 3 months to treat diabetes. Fresh fruits are also taken orally to get relief from stomachache and to treat diabetes.|||
|Young leaf is ground into a paste with goat’s milk and taken orally to treat indigestion.|
|Malayalis in South India||Paste of seeds is prepared with the combination of leaves of Momordica charantia and flowers of Cassia auriculata and taken orally once a day for 3 months to treat diabetes.|||
|Traditional medical healers in Madagascar||Seeds are taken orally for generations as the centerpiece of an effective therapy for counteracting the slow debilitating impacts of diabetes.|||
|Local population in Andhra Pradesh, India||Shade dried seeds are made into powder and taken orally thrice a day in the treatment of diabetes.|||
|Siddis in Karnataka, India||The juice obtained from the leaves is mixed with milk and taken orally early in the morning, to treat diabetes.|||
|The juice obtained from the stem bark is mixed with butter milk and taken orally every day before going to bed to treat constipation. The same recipe, when taken early in the morning on an empty stomach, is claimed to stop blood discharge in the faeces.|
|Rural population in Brazil||Leaves of jambolan are taken orally in the treatment of diabetes.|||
|Traditional healers in Brazil
||Tea prepared from the infusion or decoction of leaves is taken orally to treat diabetes.
|Tribal people in Maharastra||The tender leaves are taken orally to treat jaundice. It was claimed that the eyes, nails and urine turned yellow. The treatment was followed for 2–3 days by adults and children as well.|||
The fruits, seeds and stem bark of Syzygium cumini possess promising activity against diabetes mellitus which has been confirmed by several experimental and clinical studies and considered its primary health benefit.
There are additional important health benefits of Syzygium cumini that have been studied and published. They are listed in the Table below:
Health Benefits of Syzygium cumini (Jamun)
System Condition Benefit References
Gastrointestinal Gastroprotective A dose which consisted of 20.0 g tannins/kg rat weight showed significantly lower stomach free radical concentrations. These findings suggest that tannins extracted from S. cumini have gastroprotective and anti-ulcerogenic effects. 1
Immunity Anti-Inflammatory These observations established the anti-inflammatory effect of S. cuminii seed extract in exudative, proliferative and chronic stages of inflammation along with an anti-pyretic action. Antiinflammatory and related actions of Syzigium cumini seed extract 2
The study concluded that S. cumini exhibits inhibitory role on inflammatory response to histamine, 5-HT and PGE2. 3
The present study demonstrated that S. cumini bark extract has a potent anti-inflammatory action against different phases of inflammation without any side effect on gastric mucosa. 4
Anti-bacterial and Anti-fungal The water and methanolic extracts of Syzygium jambolanum seeds were examined for antibacterial and antifungal activity in vitro using the disc diffusion method, minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration. 5
The leaf essential oils of Syzygium cumini and Syzygium travancoricum were tested for their antibacterial property. The activity of S. cumini essential oil was found to be good, while that of S. travancoricum was moderate. 6
Radioprotective The radioprotective activity of the hydroalcoholic extract of jamun seeds (SCE) was studied in mice exposed to different doses of gamma radiation. The mice were injected with 0, 5, 10, 20, 40, 60, 80, 100, 120, 140 or 160 mg/kg body weight of SCE, before exposure to 10 Gy of gamma radiation, to select the optimum dose of radiation protection.
The mice treated with 80 mg/kg body weight SCE intraperitoneally before exposure to 6, 7, 8, 9, 10 and 11 Gy of gamma radiation showed reduction in the symptoms of radiation sickness and mortality at all exposure doses and caused a significant increase in the animal survival when compared with the concurrent double distilled water (DDW) + irradiation group. The SCE treatment protected mice against the gastrointestinal as well as bone marrow deaths and the DRF was found to be 1.24.
Syzygium cumini Linn. and Eugenia cumini (SCE) provided protection against the radiation-induced bone marrow death in mice treated with 10-60 mg/kg b.wt. of SCE. However, the best protection was obtained for 30 mg/kg b.wt. SCE, where the number of, survivors after 30 days post-irradiation was highest (41.66%) when compared with the other doses of SCE. 8
Metabolism Antioxidant These data showed that in addition to 5 anthocyanidins, jamun contains appreciable amounts of ellagic acid/ellagitannins, with high antioxidant and antiproliferative activities. 9
The leaves, bark and fruits of Terminalia arjuna, Terminalia bellerica, Terminalia chebula and Terminalia muelleri, the leaves and fruits of Phyllanthus emblica, and the seeds of Syzygium cumini were found to have high total phenolic contents (72.0-167.2 mg/g) and high antioxidant activity (69.6-90.6%). 10
From the results, using different free radical-scavenging systems, it can be said that the fruit skin of S. cumini have significant antioxidant activity. In each case, lower antioxidant values, in comparison to tea, might be due to drying condition; through which some of antioxidants are presumably degraded. The antioxidant property of the fruit skin may come in part from antioxidant vitamins, phenolics or tannins and/or anthocyanins. Consumption of S. cumini fruit may supply substantial antioxidants which may provide health promoting and disease preventing effects. 11
The present study reveals the efficacy of Eugenia jambolana seed kernel in the amelioration of diabetes, which may be attributed to its hypoglycemic property along with its antioxidant potential. The antioxidant effect of Eugenia jambolana seed kernel was also compared with glibenclamide, a standard hypoglycemic drug. 12
Diabetes/Blood glucose The present study reveals the efficacy of Eugenia jambolana seed kernel in the amelioration of diabetes, which may be attributed to its hypoglycemic property along with its antioxidant potential. The antioxidant effect of Eugenia jambolana seed kernel was also compared with glibenclamide, a standard hypoglycemic drug. 13
In view of the knowledge summarized here, a successful clinical study should use S. cumini seeds, seed kernels or fruit from India in fairly high doses. Reductions on blood sugar levels by about 30% seem reasonably to be expected. Adverse effects to be expected comprise gastrointestinal disturbances. 14
Study shows that S. cumini seed extracts reduce tissue damage in diabetic rat brain. 15
Treatment with 400 mg per day of aqueous extracts of Momordica charantia (MC) and Eugenia jambolana (EJ) for 15 days substantially prevented hyperglycemia and hyperinsulinemia induced by a diet high in fructose (63.52+/-2.9 and 66.46+/-2.2 vs. 75.46+/-2.4, respectively). 16
The oral antihyperglycemic effect of the water and ethanolic extracts of the fruit-pulp of Eugenia jambolana (EJ) was investigated in alloxan-induced diabetic with fasting blood glucose between 120 and 250 mg/dl as well as severely diabetic rabbits (fasting blood glucose above 250 mg/dl). Water extract was found to be more effective than the ethanolic extract in reducing fasting blood glucose and improving blood glucose in glucose tolerance test.
After treatment of diabetic and severely diabetic rabbits daily once with 25mg/kg, body weight with F-III for 7 and 15 days, respectively, there was fall in fasting blood glucose (38% diabetic; 48% severely diabetic) and improvement in blood glucose during glucose tolerance test (48%) in diabetic rabbits.