Ananas comosus (L.) Merr.

Last updated: 31 May 2016

Scientific Name

Ananas comosus (L.) Merr.


Ananas ananas (L.) H.Karst. ex Voss [Invalid], Ananas argentata J.C.Wendl. ex Schult. & Schult.f., Ananas aurata J.C.Wendl. ex Schult. & Schult.f., Ananas bracteatus Baker, Ananas coccineus Descourt., Ananas debilis Schult. & Schult.f., Ananas lyman-smithii Camargo [Invalid], Ananas maxima Schult. & Schult.f., Ananas monstrosus (Carrière) L.B.Sm., Ananas ovatus Mill., Ananas pancheanus André, Ananas penangensis Baker, Ananas porteanus Veitch ex K.Koch, Ananas pyramidalis Mill., Ananas sativus Schult. & Schult.f., Ananas serotinus Mill., Ananas viridis Mill., Ananassa ananas (L.) H.Karst., Ananassa debilis Lindl., Ananassa monstrosa Carrière, Ananassa porteana (Veitch ex K.Koch) Carrière, Ananassa sativa (Schult. & Schult.f.) Lindl. ex Beer, Bromelia ananas L., Bromelia communis Lam., Bromelia comosa L., Bromelia edulis Salisb. [Illegitimate], Bromelia mai-pouri Perrier, Bromelia pigna Perrier, Bromelia rubra Schult. & Schult.f., Bromelia violacea Schult. & Schult.f., Bromelia viridis (Mill.) Schult. & Schult.f., Distiacanthus communis (Lam.) Rojas Acosta. [1]

Vernacular Name

Malaysia Nanas, nanas pager [2], nanas hijau [3]
English Pineapple, ananas [2], rain tree [3]
China Feng li [3]
India Aainunnas, aanas, ainunnas, alipiong, anaci, anasapoondu, bahunetra, centalanceti, kaitaccakka, keehom, lakhuihthei, matikathal, natcattirakantaki, panantalai, parangithalai, puntalaimaram, puntalam, yeangkong pyeong, et al. [3]
Indonesia Nanas (Javanese); danas (Sundanese); nanèh (Sumatra) [2]; kayu ujan [3]
Thailand Yaannat (Peninsular); sapparot (Central); bonat (Chiang Mai) [2]; khanun thong, ling thong, maa nuea, maak keng, makhanat, manta, nae, neh sa, sapparot laai, yaanat [3]
Laos Ananas, nat [3]
Philippines Apangdan (Bontok); piña (Spanish) [2]; pinya [3]
Cambodia Maneas, moneah [2]
Vietnam Dúa, thom [2]
West Africa Akunkun, akunkun ahun, eekun ahun, ogede oyinbo, ope oyinbo, opeyibo, opeyinbo, opo oyibo, opon oyinbo (Yoruba) [3]
France Ananas, pain de sucre [2]
Mexico Tobo guela, tobo quela, xiicho [3].

Geographical Distributions

Ananas comosus has its origin in South America where it was domesticated before the time of Columbus. In the 16th Century, the Spaniards took the pineapple to the Philippines and Peninsular Malaysia and possibly also Indonesia. The crop is now widely grown throughout the tropics and into the subtropics. The international canning industry is based on plantations in Thailand, the Philippines, Malaysia and north Sumatra as well as in Hawaii, Brazil, Taiwan, South Africa, Kenya, Ivory Coast, Mexico and Puerto Rico. [2]

Botanical Description

A. comosus is member of the family Bromeliaceae. It is a perennial or biennial herb that can grow up to 50-150 cm tall. [2]

The leaves are sword-shaped, measure up to 1 m or more long, 5-8 cm wide, with spiny or almost entire margin, their top ending in a fine point, fleshy, fibrous, grooved on the upper surface, arranged in a close spiral and clasping the main axis at their base. [2]

The inflorescence is compact with numerous (up to 200) reddish-purple sessile flowers where each flower is subtended by a pointed bract. There are 3 short and fleshy sepals. There are 3 petals that form a tube which encloses 6 stamens and a narrow style with 3-branched stigma. [2]

The fruit is coenocarpium, which is formed by the extensive thickening of the axis of the inflorescence and by the fusion of the small berry-like individual fruits. The hard rind of the fruit is formed by the persistent sepals and floral bracts, which are more or less fused. On average, the fruit is cylindrical, measuring about 20 cm long and 14 cm in diametre and weighing 1-2.5 kg. The fruit is surmounted by a rosette of short, stiff, spirally arranged leaves, which is called 'crown'. The flesh is pale to golden yellow and usually seedless. Beside the 'crown', 'slips' (shoots growing on the stem below the fruit) and 'suckers' (shoots growing in leaf axils lower down the stem) formed can be used for vegetative propagation. [2]


A. comosus  is cultivated between 25°N and 25°S. The temperature for cultivation ranges from 23-32°C, although the plant can be grown in areas where temperature drops as low as 10°C. However, the plant does not tolerate frost and the fruit is sensitive to sunburn. Crop duration increases substantially further away from the equator and at higher elevations. Moreover, sensitivity to day length has the effect of making the crop more seasonal at higher latitudes. Within the limits of its distribution, the mean annual sunshine varies from about 33-71% of the maximum duration, with a mean annual value of 2000 hours. In Kenya, it is grown at elevations of 1800 m where fruits develop sugar:acid ratio of 16:1, which is ideal for canning purpose. At higher elevations, fruits become too acidic. The plants are tolerant to drought and a wide range of rainfall; 1000-1500 mm per annum is considered optimal. A well-drained sandy loam is preferred, with high organic matter content and pH 4.5-6.5. However, plants can be grown in a wide range of soil types, such as the acid peats (pH 3-5) in Malaysia. Drainage should be thorough, because waterlogged plants quickly succumb to root rot. [2]

Chemical Constituent

A. comosus  has been reported to contain sulfhydryl proteolytic enzymes namely Bromelain A and Bromelain B). [4]

Plant Part Used

No documentation.

Traditional Use

No documentation.

Preclinical Data


Antiinflammatory activity

In vivo studies reported anti-inflammatory mechanisms of action of bromelain include inhibition of bradykinin at the site of inflammation via depletion of the plasma kallikrein system, and limiting the formation of fibrin by reduction of clotting cascade intermediates. [5][6]

A study evaluating rats with collagen-induced arthritis compared cyclosporin A therapy to an enzyme complex (bromelain, trypsin, rutin) using a combination of both. 10 mg/kg of cyclosporin A and 5 mg/kg of cyclosporin A plus 300 mg/kg of enzyme complex significantly inhibited changes in measures of inflammation and the destructive effects of arthritis. [7]

Platelet aggregation activity

Bromelain has been reported to prevent platelet aggregation in vivo and in vitro [8]. Bromelain was reported to decrease aggregation of blood platelets in 17 of the subjects and normalized values in 8 of the 9 subjects who previously had high aggregation values. In vitro studies have also demonstrated that bromelain inhibits platelet aggregation stimulated by ADP or epinephrine, as well as by prostaglandin precursors, in a dose-dependent manner [9]. Bromelain has been reported to stimulate the conversion of plasminogen to plasmin, resulting in increased fibrinolysis [10]. There is a possibility that bromelain can ‘expose’ the tumour cells because of fibrinolytic activity that reduces the soluble fibrin in circulation. Bromelain also reduces platelet count which is significant in the haemostatic system whereby the formation of tumour-platelet aggregates can be prevented.  A laboratory animal study found that bromelain improves transport of heparin across the small intestine [11]

Antitumor activity

Several studies, both animal and human, indicate bromelain might have some antimetastatic ability [12][13]. It is believed bromelain plays a role in the modulating effect of neutrophils to produce reactive oxygen species (ROS) which is important for inhibition cancer cells although excess of ROS which cause oxidative stress might lead to DNA damage [11]. Bromelain plays a role in reducing the breakage of strand DNA by inhibiting Cox-2 and restrict the extracellular signal regulated protein which will reduce the percentage of tumour [14].

Immunomodulatory activity

Bromelain can reportedly induce cytokine production in human peripheral blood mononuclear cells [15]. Bromelain has also been reported to remove T-cell CD4 molecules from lymphocytes and to affect T-cell activation [16] and to enhance macrophage production of INF-gamma-mediated nitric oxide and TNF-alpha [17]. In splenocyte cultures, T-cell receptor and anti-CD28 mediated T-cell proliferation was enhanced by bromelain, while IL-2 production was decreased. IL-2 production was also inhibited in highly purified CD4+ T-cells [18]. Another study has demonstrated immune system stimulation of phagocytosis, respiratory burst and killing (PBK) in blood samples using Candida albicans as target organism [19].

Wounds debridement activity

Bromelain applied topically as a cream (35% bromelain in a lipid base) can reportedly be beneficial in the elimination of burn debris and in acceleration of healing [20]. A non-proteolytic component of bromelain may be responsible for this effect. This component, referred to as escharase, has no hydrolytic enzyme activity against normal protein substrates or various glycosaminoglycan substrates, and its activity varies greatly from preparation to preparation [21].

Proteolytic activity

Bromelain’s proteolytic activity has been reported effective for inflammatory bowel disease due to it’s anti-inflammatory effects and also since the enzymes are not affected by anti-bromelain IgG and remains within the gastrointestinal tract. [22]

Bromelain has been reported to heal gastric ulcers in laboratory animals. In an extensive study of the effect of bromelain on the gastric mucosa, it was found that bromelain reportedly increased the uptake of radioactive sulfur by 50 percent and glucosamine by 30-90 percent [23]. Increased uptake of these substances may allow the gastric mucosa to heal more rapidly [24].

Cardiovascular activity

In vivo study showed that bromelain may minimize the severity of angina pectoris [25]. A drastic reduction in the incidence of coronary infarct after administration of potassium and magnesium along with 120-400mg of bromelain per day has been reported [26].


No documentation.

Clinical Data

Clinical findings

Antiinflammatory activity

Bromelain is used as an anti-inflammatory and analgesic agent in treating the symptoms of arthritis [27][28]. The analgesic effects are reportedly due to inhibition of the arachidonic acid pathway of inflammation by selectively decreasing thromboxane generation, changing the ratio of thromboxane/prostacyclin (in favor of prostacyclin), and inhibiting PGE2 in addition to the direct effects on the nociceptors [27][29]. A few clinical trials in patients with arthritis reported statistical equivalence of pain reduction, whether they were treated with bromelain or diclofenac [30].

Bromelain affects CCL4/MIP-1b chemokine secretion through mechanism whereby it reduces the amount contained in the inflamed tissues derived from inflammatory bowel disease (IBD) patients [11]. The breakdown of proteins by Bromelain is futher supported by the mechanism acting on cell-surface CD25 which will decrease CD4+T cells that contributes to anti-inflammatory benefits [31]. Bromelain plays a role in neutrophil migration by abrogating a particular cell surface known as CD128 receptor which prevents the union of leukocytes to blood vessels [32].

Another potential use for bromelain includes treatment of breast engorgement. A literature review evaluated numerous therapies for breast engorgement. Of the pharmacological therapies evaluated, a bromelain-trypsin complex as well as serrapeptase (Danzen), an anti-inflammatory agent, demonstrated significant improvement in engorgement symptoms over placebo, whereas oxytocin did not. [33]

Platelet aggregation

In one study, bromelain was administered orally to 20 volunteers with a history of heart attack or stroke, or with high platelet aggregation values. [34]

Antitumour activity

In high dosages (over 1000 mg daily), bromelain has been combined with chemotherapeutic agents such as 5-FU and vincristine, resulting in tumor regression [35]. Bromelain was also reported to stimulate deficient monocytic cytotoxicity of mammary tumor patients, which may partially explain its proposed antitumor activity [36]. Consumption of proteinases, including bromelain, trypsin and rutoside was found to form intermediate forms of alpha 2-macroglobulin. These intermediate forms had high affinity to TGF-beta, eliminating the TGF-beta effect on fibroblasts in cell culture. This demonstrates that treatment of cancers associated with high TGF-beta concentration may benefit from proteinase therapym [37].

Immunomodulary activity

The use of bromelain has been reported to lead to the production of tumor necrosis factor-alpha, interleukin-1-beta, and interleukin-6 in a time- and dose-dependent manner. [38]

Digestive aid

Bromelain has reportedly been used successfully as a digestive enzyme following pancreatectomy, in cases of exocrine pancreas insufficiency and in other intestinal disorders [39][40]. The combination of ox bile, pancreatin and bromelain is reportedly effective in lowering stool fat excretion in patients with pancreatic steatorrhea, resulting in a symptomatic improvement in pain, flatulence, and stool frequency. [41]

Potentiation of antibiotics

Antibiotic potentiation is a primary use of bromelain in some foreign countries. In humans, some undetermined activity of bromelain has been documented to increase blood and urine levels of antibiotics [42][43][44]. Several studies have reported increases in the serum level of tetracycline after oral ingestion of bromelain [45][46]. Bromelain combined with antibiotic therapy has been reported to be more effective than antibiotics alone in a variety of conditions including pneumonia, bronchitis, cutaneous staphylococcus infection, thrombophlebitis, cellulitis, pyelonephritis, perirectal and rectal abscesses, and sinusitis [47][48].

Surgical procedures and musculoskeletal injuries

One of bromelain's most common applications is in the treatment of inflammation and soft tissue injuries. It has been reported to speed healing of bruises and hematomas [49]. Treatment with bromelain following blunt injuries to the musculoskeletal system has resulted in a clear reduction in swelling, pain at rest and during movement, and tenderness [50]. Administration of bromelain pre-surgically can reportedly reduce the average number of days for complete disappearance of pain and inflammation [51][52]. In a dose dependent manner, bromelain was shown to be able to improve the mild acute knee pain on treatment groups although more studies need to be done to confirm [28].

Cardiovascular activity

In a study involving 73 patients with acute thrombophlebitis, bromelain plus analgesics was reported to decrease symptoms of inflammation including pain, edema, tenderness, skin temperature, and disability [53]. Administration of 400-1000 mg/day of bromelain to 14 patients with angina pectoris resulted in the disappearance of symptoms in all patients within 4 to 90 days [54].

Mucolytic activity

A decrease in the volume and purulence of sputum was reported with the use of bromelain in a clinical study of 124 patients hospitalized with chronic bronchitis, pneumonia, bronchopneumonia, bronchiectasis, or pulmonary abscesses. [55]


Based on pharmacology, use with caution in individuals with bleeding disorders. [56]

Side effects

In large doses (up to 1840 mg), bromelain was reported to increase blood pressure in hypertensive patients. [57]

The allergenic potential for proteolytic enzymes should not be underestimated. Bromelain may cause IgE-mediated respiratory allergies of both the immediate type and the late-phase of immediate type in sensitive individuals [58]. Bromelain was reported to cause allergic symptoms in approximately 28 percent of individuals with IgE allergic response to honey bee venom [59].

Pregnancy/Breast Feeding

No documentation.

Age limitation

No documentation.

Adverse reaction

No documentation.

Interaction & Depletion

Interaction with drug

Anticoagulant medications

Studies have reported that Bromelain affects the blood's clotting ability and may alter the effects of these medications and possibly the dose needed for treatment. Use with caution [8]. These drugs include warfarin, heparin, dalteparin, tinzaparin, enoxaparin, danaparoid sodium, antithrombin III, lipirudin, argatroban, bivalirudin,

Antiplatelet medications

Studies have reported that Bromelain affects the blood's clotting ability and may alter the effects of these medications and possibly the dose needed for treatment. Use with caution [8]. These drugs include aspirin, dipyridamole, anagrelide, cilostazol, clopidogrel, ticlopidine, abciximab, tirofiban, eptifibatide


Human studies have reported that bromelain may increase the amount of antibiotic in the blood and urine increasing the effects of these medications. Use with caution [42][43][44][45][46]. These drugs include amoxicillin, tetracycline, gentamicin, penicillin

Specific chemotherapeutic medications

A human study reported that bromelain increased the action of a chemotherapeutic agent, possibly altering the dose needed for treatment. Use with caution [27][48]. These drugs include fluorouracil (5-fluorouracil, 5-FU), vincristine

Interaction with other Herbs

No documentation.


No documentation.

Case Report

No documentation.


No documentation.

Poisonous Management

No documentation.

Line drawing


Figure 1: The line drawing of A. comosus [2]


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