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Try out PMC Labs and tell us what you think. Learn More. The resin of Boswellia species has been used as incense in religious and cultural ceremonies and in medicines since time immemorial. Oleo gum-resin is tapped from the incision made on the trunk of the tree and is then stored in specially made bamboo basket for removal of oil content and getting the resin solidified.

After processing, the gum-resin is then graded according to its flavour, colour, shape and size. Regionally, it is also known by different names. Gum-resin extracts of Boswellia serrata have been traditionally used in folk medicine for centuries to treat various chronic inflammatory diseases. The resinous part of Boswellia serrata possesses monoterpenes, diterpenes, triterpenes, tetracyclic triterpenic acids and four major pentacyclic triterpenic acids i.

Since time immemorial, plants and their products have been the primary resource of food, shelter, clothing, flavors, fragrances as also valuable ingredients for medicines for mankind. In this context, natural resins have played an important role. These have also been used as adhesives, as ingredients for cosmetic preparations, as fragrances in daily rituals and in religious ceremonies, as coating materials and also for their different curative powers[ 1 — 3 ].

In ancient times, Hindus, Babylonians, Persians, Romans, Chinese and Greeks as well as the people of old American civilizations used natural resins primarily for embalming and for its incense in cultural functions. They firmly believed that when these materials get in contact with fire, the smoke and the fragrance they produce, not only soothe their souls but also please their gods.

Burning of these natural resins had become an important component of their cultural life. They burned these resins during sacrificial ceremonies and in their daily rituals to prevent the influence of evil spirits on their souls or to honour the dead or living ones[ 4 — 6 ].

The family of Burseraceae is represented in the plant kingdom with 17 genera and species wide-spread in all tropical regions. There are about 25 known species belonging to Genus Boswellia , most of them occur in Arabia, northeastern coast of Africa and India. Boswellia frereana Birdw. This is the most expensive brand of resin in the market[ 11 ]. Another resin producing species is Boswellia serrata Roxb. It has been available as a high quality extract in India for nearly 25 years and marketed under the name Shallaki.

The botanical origin and vernacular names of Boswellia serrata are given in Table 1. Salai , an oleo gum-resin, is a plant exudate of genus Boswellia Family: Burseraceae. It is tapped from the incision made on the trunk of the tree, which is then stored in specially made bamboo basket.

The residue, semi-solid to solid part, is the gum-resin which hardens slowly into amorphous, tear-shaped products with an aromatic scent. Then, it is broken into small pieces by wooden mallet or chopper and during this process all impurities including bark pieces etc.

The gum-resin is then graded according to its flavour, colour, shape and size. Generally four grades i. The fresh gum obtained from the tree is hot with pleasant flavour and slightly bitter in taste. It is generally used in making incense powder and sticks.

The resins have a fragrant aroma because of the presence of essential oils and this accounts for their commercial importance. The essential oil of gum-resin is one of the most commonly used oils in aromatherapy, paints and varnishes. Pure oleo gum-resin collected in the optimum season hardens slowly, retaining its golden colour and transparency. But the colour varies from golden brown to dark brown or dark greenish-brown depending on the locality, season, size of the tree and the wound-surface, collection process and storage.

Darkening of colour of resin is also due to autoxidation, polymerization and enzymatic reactions. The resin is generally harvested all through the summer and autumn after the tree has been wounded in March or April. Boswellia tree can produce exudates in good quality only for three years. After this period, the quality of the collected resin decreases considerably. Therefore, the tree should be left to rest for some years after harvesting period. Boswellia serrata is one of the ancient and most valued herbs in Ayurveda.

Three renowned ancient texts form the pillars of classical Ayurvedic Science, which has its roots in India: Charaka's Charaka Samhita c. The first two pillars of Ayurveda describe the antirheumatic antiarthritis activity of gugguls -the gum-resins of trees[ 16 — 20 ].

In addition to its beneficial use for arthritis, this gummy resin is also mentioned in traditional Ayurvedic and Unani texts as an effective remedy for diarrhoea, dysentery, ringworm, boils, fevers antipyretic , skin and blood diseases, cardiovascular diseases, mouth sores, bad throat, bronchitis, asthma, cough, vaginal discharges, hair-loss, jaundice, hemorrhoids, syphilitic diseases, irregular menses and stimulation of liver.

It is also diaphoretic, astringent, diuretic and acts both as internal and external stimulant. Modern medicine and pharmacology strongly point out to its use as an antiarthritic, antiinflammatory, antihyperlipidemic controls blood lipids , antiatherosclerotic anticoronary plaque , analgesic pain-reliever and hepatoprotective protects the liver [ 15 , 21 — 24 ].

The structures of four major pentacyclic triterpenic acids boswellic acids as also some of their characteristic features are given in fig. In vitro studies and animal models show that boswellic acids were found to inhibit the synthesis of pro-inflammatory enzyme, 5-lipoxygenase 5-LO including 5-hydroxyeicosatetraenoic acid 5-HETE and leukotriene B4 LTB-4 , which cause bronchoconstriction, chemotaxis, and increased vascular permeability[ 33 — 38 ]. Other antiinflammatory plant constituents, such as quercetin, also block this enzyme, but they do so in a more general fashion, as an antioxidant, whereas boswellic acids seem to be specific inhibitor of 5-LO[ 39 ].

In contrast to non-steroidal antiinflammatory drugs NSAIDS , which are well known to disrupt glycosaminoglycan synthesis, thus accelerating articular damage in arthritic conditions, boswellic acids have been shown to significantly reduce glycosaminoglycan degradation[ 40 — 43 ]. In vivo study examining the effect of Boswellia extract and ketoprofen on glycosaminoglycan metabolism showed that Boswellia considerably reduced the degradation of glycosaminoglycans compared to controls, whereas ketoprofen caused a reduction in total tissue glycosaminoglycan content[ 44 ].

In vitro studies by Ammon et al. Boswellic acids were, therefore, shown to be specific, non-redox inhibitors of leukotriene synthesis, either interacting directly with 5-LO or blocking its translocation[ 45 , 46 ]. Boswellic acids have also been observed to inhibit human leukocyte elastase HLE , which may be involved in the pathogenesis of emphysema.

HLE also stimulates mucus secretion and thus may play a role in cystic fibrosis, chronic bronchitis and acute respiratory distress syndrome[ 47 , 48 ]. HLE is a serine protease, which initiates injury to the tissues which, in turn, triggers the inflammatory process. This dual inhibitory action on the inflammatory process is unique to boswellic acids. Singh et al. It also showed antipyretic effect, with no ulcerogenic effect.

Kulkarni et al. However, the clinical trials of gum-resin of Boswellia alone have shown to improve symptoms in patients with osteoarthritis, and rheumatoid arthritis[ 52 , 53 ]. The boswellic acid from Boswellia serrata , when tested on new model i.

Since the new model is reported to be sensitive to slowly acting remission-inducing drugs, its effectiveness on boswellic acid throws some light on its mechanism of action, which seems to be unlike aspirin and steroidal drugs[ 54 ].

Poeckel and Werz in have summarized the biological actions of boswellic acids on the cellular and molecular level and attempted to put the data into the perspectives of the beneficial effects manifested in animal studies and trials with human subjects related to inflammation and cancer[ 55 ].

Sharma et al. Gayathri et al. Incensole acetate, a novel antiinflammatory compound isolated from Boswellia resin inhibits nuclear factor-kappa B activation[ 58 ]. Boswellic acids are direct 5-LO inhibitors that efficiently suppress 5-LO product synthesis in common in vitro test models.

However, the pharmacological relevance of such interference in vivo seems questionable[ 59 ]. A clinical trial conducted by Raychaudhuri and co-workers in India has shown that the extract of the plant, Boswellia serrata , can reduce pain and considerably improve knee-joint functions, in some cases providing relief even within seven days.

Raychaudhuri and her colleagues described their study as the first to evaluate the efficacy of the extract enriched with a form of boswellic acid on osteoarthritis[ 61 ].

Very recently, Pawar et al. Boswellia is generally taken as a capsule, tablet or its bark decoction orally. The recommended dosage is based on historical practice or available trials.

Presently, it is not clear what the optimal dose is to balance safety and efficacy. The manufacturing of Boswellia products varies from one produce to the other and this makes it even more difficult for standardization to happen.

It is important to note that most of the trials used various products made by various manufacturers, so clinical effects may not be comparable[ 63 , 64 ].

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Conclusion: These findings suggest that methanol extract of Eclipta alba may have potential as a hair growth promoter. Abstract Ethnopharmacological relevance: Eclipta alba is traditionally known to potentiate hair growth promotion.