Benzoin (Gawi)

Origin: it is the balsamic resin obtained by incision of stems of Styrax benzoin (Sumatra benzoin) and Styrax tonkinensis (Siam benzoin) (Fam. Styracaceae).

Uses:

Sumatra benzoin:

1.   Antiseptic.

2.   Expectorant.

3.

   As ointment in skin disease.

Siam benzoin:

1.   In perfumes.

2.   Cosmetic lotions.

Test for identity

1.   Warm 0.5g powders with KMnO₄ a faint odour of benzaldehyde with sumatra benzoin only.

2.   Alcoholic solution with alcoholic solution of FeCl₃ green colour with Saim benzoin due to siaresinitannol, negative with Sumatra benzoin.

3.   Extract with ether, filter to 1ml of filtrate add 2-3 drops of H₂SO₄ deep purplish-red colour with Saim benzoin, deep reddish-brown with Sumatra benzoin.

4.   Sublimation test: heated benzoin evolves white fumes of cinnamic and benzoic acids. Which readily condense on a cool surface as plate crystals in benzoin and rods crystals in cinnamic.

Report

Test	Result
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