Manjakani or oak gall is a plant excretion produced as a result when irritants are released by the larvae of gall-wasp on oak trees such as the Quercus Infectoria oak tree; which is a small native tree of Greece , Asia Minor and Iran .

The main constitutes found in the oak galls are tannin consisting 50% to 70% and small amount of free gallic acid and ellagic acid.

In Malaysia , the galls are used in combination with other herbs as a drinking remedy by women after childbirth to restore the elasticity of the uterine wall. In India, it is known as Majuphal and is used as dental powder and in the treatment of toothache and gingivitis.

The galls of Quercus Infectoria have also been pharmacologically reported to be powerfull astringent, used to check diarrhea and dysentery. It is also documented to possess antidiabetic, antitremorine, local anaesthetic, antiviral, antibacterial, antifungal, larvicidal and anti-inflammatory activities.