Yellow Aloe? What's Wrong?

 Aloe vera contains two kinds of 'sap' that are used medicinally. The thick yellow sap that comes from the inner lining of the leaf is called Aloe latex, and contains aloin, a powerful laxative. It flows for a little while after cutting a leaf, and can be scraped off the leaf epidermis. It is also called Aloe juice. The laxative effect of aloin is primary reason why the desert Bedouin people of Arabia cultivated Aloe vera. It has been in cultivation so long that there is no known natural population of the plant.

 The second kind of sap is called Aloe gel, and is contained in clear tissue of the inner leaf. This is the part of the plant that is soothing to skin.

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