Extractive 2

Question 1

THREE CLASSIFICATIONS OF EXTRACTIVES:

Answer 1

1. AROMATIC PHENOLIC COMPOUNDS
2. ALIPHATIC COMPOUNDS
3. OTHER COMPOUNDS

Question 2

• found in the bark and heartwood

Answer 2

AROMATIC PHENOLIC COMPOUNDS

Question 3

-serve the purpose of protecting lignocellulose from fungal
and microbial attack and can be washed out as “resin”
from live trees

Answer 3

AROMATIC PHENOLIC COMPOUNDS

Question 4

• have direct effect on fungal physiology

Answer 4

AROMATIC PHENOLIC COMPOUNDS

Question 5

AROMATIC PHENOLIC COMPOUNDS:

Answer 5

A. Flavonoids
B. Stilbenes
C. Tannins
D. Lignan

Question 6

• secondary metabolites that occur naturally in all plant families

Answer 6

Flavonoids

Question 7

• Widely distributed in all parts of plants, these compounds afford
  protection against ultraviolet radiation, pathogens, and herbivores

Answer 7

Flavonoids

Question 8

• have an important effect on the durability of wood

Answer 8

Flavonoids

Question 9

flavanoids protects heartwood against fungal colonization by a dual function:

Answer 9

• fungicidal activity and
• free radical scavengers
  (antioxidants)

Question 10

flavanoids are _________ and have received attention due to their role in the neutralization or scavenging of free radicals

Answer 10

natural antioxidants

Question 11

• produced naturally by several plants upon attack by pathogens

Answer 11

Stilbenes

Question 12

• produced by woody plants as stress metabolites and also as constitutive defensive
  agents
• compounds possessing the 1,2-diphenylethene structure

Answer 12

Stilbenes

Question 13

Stilbenes are large class of plant secondary metabolites, belonging to ________

Answer 13

polyphenols

Question 14

widely distributed in food (grapes, peanuts, and other foods) and
medicinal plants,

Answer 14

stilbenes

Question 15

stillbenes possess a variety of biological activities, including antitumor, anti- inflammatory, antioxidant, antibacterial, and antiviral activities

Answer 15

true

Question 16

stillbenes have two isomeric forms of 1,2-diphenylethylene:

Answer 16

• trans-stilbene and
• cis-stilbene

Question 17

Hydroxylated trans-stilbene has an
important role in heartwood ________, especially for a resistance to fungal decay

Answer 17

durability

Question 18

The durability and resistance to
decay by Pinus sylvestris (Pinaceae)
is due to _______

Answer 18

pinosylvins

Question 19

constitute a distinctive and unique group of higher plant metabolites

Answer 19

Tannins

Question 20

thought by some to constitute one of the most important groups of
higher plant defensive secondary metabolites

Answer 20

Tannins

Question 21

of tannin includes compounds of two distinct chemical groups:

Answer 21

• hydrolysable tannins and
• condensed tannins

Question 22

molecules with a polyol (D-
glucose) as a central core, the hydroxyl groups of these
carbohydrates are partially or totally esterified with phenolic groups like gallic acid (gallotannins) or ellagic acid (ellagitannins)

Answer 22

hydrolysable tannins

Question 23

hydrolysable tannins are usually
present in ________ in plants

Answer 23

low amounts

Question 24

probably the most ubiquitous of all plant phenolics, and presented exceptional concentrations in the barks and heartwoods of a variety of tree species

Answer 24

Condensed tannins

Question 25

- natural preservatives and antifungal agents, found in high concentrations in the bark and wood of some tree species

Answer 25

Condensed tannins

Question 26

large group of chemical compounds found in plants

Answer 26

Lignan

Question 27

a group of phenylpropanes dimers, where the phenylpropane units were linkages by the central carbon (carbon number 8) of their side chains, as one of the extractives located mainly in the lumen cell

Answer 27

Lignan

Question 28

Non structural in nature but play role in plant defense against biotic and abiotic stresses

Answer 28

Lignan

Question 29

ALIPHATIC COMPOUNDS Groups:

Answer 29

1. Terpenes 2. Terpenoids

Question 30

- also known as secondary metabolites - belong to the biggest class of secondary metabolites - they are simple hydrocarbons

Answer 30

Terpenes

Question 31

- complex or modified type of terpenes

Answer 31

Terpenoids

Question 32

- majority of the __________ with the variation in their structures are biologically active and are used worldwide for the treatment of numerous diseases

Answer 32

Terpenoids

Question 33

TYPE OF TERPENOID:

Answer 33

1. Monoterpenes 2. Sesquiterpenes 3. Diterpenes 4. Sesterpenes 5. Triterpenes 6. Meroterpenes

Question 34

OTHER COMPOUNDS:

Answer 34

A. QUINONES

Question 35

- classified as an allelochemical that is a natural insect repellent and toxic substances

Answer 35

QUINONES

Question 36

ubiquitous biological pigments found in a range of living organisms (bacteria, fungi, higher plants, and in few animal)

Answer 36

QUINONES

Question 37

heartwood of __________ L. f. (Lamiaceae) contains a large amount of quinones that possess considerable influence on the natural durability of teak wood

Answer 37

Tectona grandis