This document discusses Taxus bark and pine bark. Taxus bark comes from yew trees and contains the active compound paclitaxel, which is used to treat cancers. It works by stabilizing microtubules to block cell proliferation. Side effects include low blood counts and nerve pain. Pine bark contains proanthocyanidins, catechins, and acids that have anti-inflammatory and antioxidant effects and is used to treat inflammation and fragility. It is stable under processing conditions.

1. Bark,
Wood
And
Galls
Lecture-3
By
Dr. Ahmed Metwaly

2. Taxus bark.
1. Origin.
2. Macroscopical properties.
3. Active constituents.
4. Uses.
5. Mechanism of action.
6. Side effects
Pine bark
1. Origin.
2. Macroscopical properties.
3. Active constituents.
4. Uses.
5. Chemical test.

3. Dried stem bark of Taxus brevifolia, Family: taxaceae.
Syn. Pacific (western) Yew

4. Small trees or shrubs in the
yew family. They are relatively
slow-growing and can be very
long-lived.
Thin, dark reddish or purplish
scales shed off the trunk and
expose a rose-coloured
underbark.

5. The Taxaceae is a small family with one main
genus, Taxus, which has an ancient reputation
as a toxic and magical plant. The yew tree was
used in ancient Greece and Rome to produce
weapons.
An alkaloidal Taxus fraction, which was named
“taxine” by Lucas (1856), is highly cardiotoxic
and has been implicated in many stock
poisonings and human poisonings.

6. In 1966 Dr. Monroe Wall isolated the active
principle, paclitaxol. Molecular structure of
paclitaxol was published in 1971; it is a
complex diterpenoidal alkaloid with an ester
side chain and a unique oxetane ring.
the approval of TAXOL® (Paclitaxel) for
marketing in December of 1992 was the
result of 30 years of work that began with
the collection of Taxus brevifolia in
Washington state in 1962.”

7. Paclitaxel

8. Rotated paclitaxel molecule model

9. The plant need to be mature( about I00 years)
to be large enough for exploitation of its
bark. At this age the tree will be some 6-9 m
high, and have a trunk of about 25 cm in
diameter.
It requires the bark from about three mature
100-year-old trees to provide one gram of
taxol.
And a course of treatment may needs 2 gms of
taxol.

10. Taxol is now the best known and most studied
member of the taxane diterpenoidal
alkaloids, or taxoids.
It is only one of over 350 members of this
compound class.
The reported taxol yield was 0.02% from dried
bark of T. brevifolia
Taxol was also reported to be present in other
Taxus species, including T. baccata and T.
cuspidata.

11. in the therapy of
breast, ovarian and lung cancers

12. Researchers determined that
Paclitaxel binds to
microtubules, stabilizes
them against
depolymerisation and thus
blocks cell proliferation.
Complex of α, β tubulin subunits
and paclitaxel. Paclitaxel is showed
as yellow stick.

13. Today, paclitaxel is obtained either from
 Tissue cultures of variousTaxus species or
 Semisynthesis from baccatin III and 10-
deacetylbaccatin III, which can be extracted in
sufficient amounts from leaves and twigs of the
common yew ( T. baccata), a tree that grows
much faster than T. brevifolia.
 Other approaches have involved the use of
endophytic fungal fermentation.
 Docetaxel (Taxotere®) is a side-chain analogue
of taxol, more water-soluble and slightly more
active than paclitaxel. It can be produced
semisynthetically from10-deacetylbaccatin III.

15.  Taxol is given as an injection or infusion into the
vein (intravenous, IV).
 There is no pill form of Taxol.
 Taxol is an irritant. An irritant is a chemical that
can cause inflammation of the vein through
which it is given.
 Because severe allergic reactions have occurred
in some people taking Taxol, patient will be
asked to take medications to help prevent a
reaction.
 Taxol is given over various amounts of times and
in various schedules.

16.  Low blood counts.
 Hair loss.
 Arthralgias and myalgias, pain in the joints
and muscles.
 Peripheral neuropathy (numbness and
tingling of the hands and feet)
 Nausea and vomiting (usually mild)
 Diarrhea.
 Mouth sores.
 teratogenicity.

18. Dried stem bark of pinus pinaster,
family pinaceae
Synonym: Pinus maritima

19. is a medium-size, reaching 20–35 m
tall and with a trunk diameter of up to 1.2.
is orange-red, thick and deeply
fissured at the base of the trunk, somewhat
thinner in the upper crown.

20.  proanthocyanidins
 Flavonoids like catechin, epicatechin
 phenolic acids (such as ferulic acid and
caffeic acid)
 the patented extract called "Pycnogenol®"

21. Catechin
Proanthocyanidins
Epicatechin

22.  Anti-inflammatory
 Antioxidant
 Antimicrobial
 Capillary Fragility treatment
 Some researches reported an antidiabetic
activity for "Pycnogenol®"

23. Pine bark extract is found to be very stable
under thermal conditions and comparatively
stable under acidic conditions. Thus, pine
bark extract is easier to handle during
processing or manufacturing steps and
remains stable when exposed to the human
digestive tract.

24.  For flavonoids

26. Taxus bark.
1. Origin.
2. Macroscopical properties.
3. Active constituents.
4. Uses.
5. Mechanism of action.
6. Side effects
Pine bark
1. Origin.
2. Macroscopical properties.
3. Active constituents.
4. Uses.
5. Chemical test.