Page 10 - Major Gum Resin-E-Book

Chapter Name

INTRODUCTION

lant based resins and gums are important forest by-products which find applications
Pin the day to day activities of the mankind since human evolution. A large number
of plant species are known to exudate resins and gums, but commercial harvesting has
been limited to Leguminosae, Combretaceae and Sterculiaceae family in case of gums;
whereas, Pinaceae, Dipterocarpaceae, Burseraceae and Umbelliferae are common among
resin yielding plant families. Other than plant exudates, gums are also obtained from seeds,
seaweed and microorganisms (www.fao.com). Gum-resins are yet another class of materials.
These are mixtures of gums and resins in different proportions and hence, are incompletely
soluble in water. Certain gum-resins that also contain essential oils are known as oleo-gum-
resins. All these materials are covered in a single term natural resins and gums (NRGs).

NRGs
Classification of plant originated NRGs

Tree exudates Seed originated
Locust bean
gum, Guar gum,
Tamarind gum,
Cassia tora, etc.
Gums: Resins: Gum-resins:
ghatti, acacia, Pine resin, dammar, Guggul,
karaya, jhingan, dikamali, sandarac, Asafoetida,
palas, neem, etc. copal, etc. myrrh, salai,
etc.

Classification of plant originated NRGs
Gums

Most of the gums are exudated as metabolic by-products of plant tissues either in normal
course or often as a result of disease or injury to the bark or wood of certain plants. These
are generally insoluble in organic solvents; they are either water soluble or hydrate in

Major gum and resin plants of India 1