Balsam of Peru
Peruvian balsam, Peru balsam,Indian black balsam, Balsamum peruvianum
Peru balsam is obtained by heating and scorching the trunk of Myroxylon balsamum var. Pereirae belonging to family Fabaceae (Leguminosae). It is an aromatic resinous pathological product obtained by injuring the large source tree that is slightly different from the one producing balsam of tolu. Peru balsam is official in many pharmacopoeias including British and Europian Pharmacopoeia.
Balsam of Peru is produced chiefly in Central America with El Salvador being the largest exporter. Besides El Salvador, balsam of peru is produced in Hondurus and Guatemala. The source plant has also been introduced in Sri Lanka and Florida.
It is called balsam of peru as it was imported from Callao via Peru, although the source plant in not indigenous to Peru. Nicolas Monardes, the acclaimed spanished physcian and botanist knew about it during the fifteenth century. The drug was first officially documented in German Pharmacopoeia.
Cultivation and Collection and preparation
It is collected from wild adult trees, the trees are 20 to 40 meters in height and the drug is obtained by injuring the plant. In the months of November and December narrow strips around 6 x 12 inches long are hammered with blunt end of axe and then scorched with torch, the balsam forms after one week of this injury. Two weeks after injuring the plant the bark is pulled and boiled in water to recover balsam of peru. The trunks also exude balsam due to injury, it is collected by wrapping rags around the trunk , once the rags get saturated with exudes it is gently boiled with water and squeezed to recover the balsam. The balsam sinks to the bottom of the container and water is decanted to collect the produce. Less invasive methods of preparation have been investigated, it includes the removal of narrow strips of bark and gentle hammering is done with hot iron, the trees are not scorched. This process reduces the recovery time of the tree to six months compared eight years it would otherwise take.
Appearance: A dark brown, viscous liquid, which is transparent and yellowish-brown when viewed in a thin layer. It is not sticky, non-drying and does not form threads. Odour: Aromatic vanilla like. Taste: Bitter and acrid. Relative Density: 1.140 to 1.117 Saponification value: 230 to 255 when determined by procedure laid down by European pharmacopoeia 5. Solubility: practically insoluble in water, freely soluble in ethanol, not miscible with fatty oils, except for castor oil.
Standards for medicinal use
As per European pharmacopoeia 5 It contains not less than 45.0 per cent m/m and not more than 70.0 per cent m/m of esters, mainly benzyl benzoate and benzyl cinnamate.
. The chief balsamic esters present are benzyl cinnamate, benzyl benzoate and styracin. Small amounts of vanillin and free cinnamic acid are also present. Around 28% resin consisting maily of perueesinotannol , nerolidol, farnesol , benzlyl alcohol is also present.
- When 200mg of balsam of peru is dissolved in 10ml of alcohol green to olive green colour develops.
- Thin layer chromatography using silica gel is performed in accordance with the procedure mentioned in European pharmacopoeia to identify balsam of peru.
Balsam of peru is often adulterated with Rosin, gum benzoin liquefied with little alcohol, storax and in some cases caster oil. Adulteration can be suspected by measuring relative density. Unadulterated balsam of peru has relative density between 1.140 and 1.117. Adulteration with artificial balsams is detected by shaking 200mg of sample in a test tube with 6ml of light petroleum, presence of any colour indicates adulteration. Adulteration with fatty oils like caster oil can be detected by shaking 1 gram of sample with 3ml of 1kg/litre solution of chloral hydrate solution. The solution thus obtained should be as clear as the original 1kg/litre solution of chloral hydrate solution.
It is used externally for treatment of scabies, wounds, ulcers and bedsores. It has also been used in suppositories for treatment of haemorrhoids due to its anal muscle relaxing properties. Earlier it was used as an ingredient of cough suppressant syrup. Dentists use it for treating dry socket, it may be a component of dental cement. Balsam of peru demonstrates antifungal and antiseptic properties. Some insect repellents incorporate balsam of tolu to improve acceptability.
Peru of balsam finds application in perfume, food and cosmetic industry.
A positive patch test performed by 10% Balsam of Peru in petrolatum indicates potential allergy to spices and/or allergy to fragrances and essential oils.
- Trease and Evans Pharmacognosy 15th edition.
- Pharmacognocy by C.K Kokate, A.P. Purohit, S.B. Gokhale 45th Edition
- European Pharmacopoeia 5th Edition
- ILDIS World Database of Legumes