Pharmacognosy Curriculum Demo

Report
Herbal Constituents
Supportive Science for Botanical Medicine
© Lisa Ganora 2008
An Isolated Phytomolecule
• Isolated digitoxin is used in
contemporary pharmacy
• Cardiac glycoside, extracted from
Foxglove (Digitalis purpurea or
D. lanata)
A Phytochemical in a Matrix
The ascorbic acid molecule is exactly the same in
Oranges or Violets, but is embedded in very
different chemical matrices
Functional Groups
•
•
•
•
•
•
•
•
•
•
•
•
Alcohol
Ketone
Aldehyde
Carboxylic acid
Ester
Ether
Amine
Amide
Sulfide
Sulfoxide
Methyl
Phenyl
R = any carbon backbone
Constituents: Major Categories
• Carbohydrates
• Lipids
• Amino acids &
derivatives
• Phenolic compounds
• Terpenoids
• Steroids
• Alkaloids
•• simple
phenols
betalain
alkaloids
•• phenolic
monosaccharides
acids
diterpenoid
alkaloids
•• phenylpropanoids
indole
alkaloids
oligosaccharides
fatty
acids
• coumarins
isoquinoline alkaloids
polysaccharides
••• lignans
oils
(triacylglycerols)
sulfur
compounds
methylxanthines
•• stilbenoids
waxes
(Garlic)
monoterpenoid
alkaloids
••• xanthones
monoterpenes
alkamides
(including
peptide
alkaloids
glucosinolates
•• styrylpyrones
pyrrolidine
alkaloids
sesquiterpenes
isobutylamides)
cyanogenic
glycosides
•• flavonoids
piperidine
essential
oils
•• isoflavonoids
5-HTP alkaloids
alkaloids
•• pyrrolizidine
steroidal
saponins
diterpenes
•• benzofurans
amines alkaloids
quinoline
•• phytosterols
triterpenes
& saponins
•• chromones
enzymes alkaloids
quinolizidine
•• cardiac
glycosides
tetraterpenes
• quinones
tropane alkaloids
• (carotenoids)
phloroglucinols
Immunomodulating Polysaccharides
• Stimulate non-specific immunity
• Echinacea: glucuronoarabinoxylans
(glucuronic acid + arabinose + xylose) &
arabinorhamnogalactans (arabinose
+ rhamnose + galactose) &
arabinogalactans
• Others in Eleuthero, Baptisia,
Calendula, Panax ginseng
• Larix (Larch) has arabinogalactans
Baptisia
Fatty Acids: Omega Series
• Tells where the double bonds are in the
molecule
• Omega 6’s & Omega 9’s common in diet
• Omega 3’s come from Flax & fish oils
Alpha-linolenic
acid (ALA),
EPA,
acid,
DHA
– eicosapentaenoic
docosahexaenoic
acid,
from
Flax
seed
from
fish
oils:
Omega
from
cold-water
fishoil:
oils:3
Omega
Omega
3 3
Isobutylamides
• Isobutylamides are a type of alkamide
• Echinacea purpurea & E. angustifolia
have the highest concentrations
• Contribute to immunomodulating effect
• Stimulate phagocytosis
• COX-2 inhibitors
(anti-inflammatory)
Sulfur Compounds in Garlic
• Alliin (major cysteine sulfoxide in Garlic) +
• Alliinase (an enzyme in fresh, whole Garlic or
correctly dried Garlic powders)
•  Allicin, the active antibiotic compound
• Allicin  sulfides, ajoene, dithiins, etc.
Alliinase
Alliin
Allicin
Flavonoids
• Largest class of polyphenols: ~ 4,000 kinds
• Often responsible for yellow or red/blue/purple
colors in flowers, fruits, vegetables
• Serve as antioxidants for the plants during
photosynthesis
• Includes antioxidant, anti-inflammatory, cancerpreventative, & cardioprotective compounds
Why are Flavonoids Good
Antioxidants?
Structures responsible for antioxidant
activity include:
–OH groups at positions 3’ and 4’ on ‘B’ ring
B
A
C
Quercetin has all three
features – an excellent
antioxidant
–OH group at position 3 with
double bond between
carbons 2 & 3; next to =O at
position 4 on ‘C’ ring
–OH group at position 5 on ‘A’
ring next to =O and –OH on
‘C’ ring
Monoterpenes & Sesquiterpenes
• Monoterpenes: 10 carbons
• Sesquiterpenes: 15 carbons
7
1
2
14
15
5
13
6
3
2
8
4
1
4
3
6
5
8
7
9
10
Menthol
Nerolidol
10
9
12
11
Antiseptic Monoterpenes
• Cineole (1,8-cineole or eucalyptol) is the major
constituent of Eucalyptus oil (~ 70 – 85%)*
• Antiseptic, antibacterial, expectorant
• Excreted through lungs: bronchitis
• α-Pinene, a minor constituent (up to
14%) is toxic in very high doses
Cineole
α-Pinene
Triterpenes & Steroids
•
•
•
Triterpenes
~ 4,000 different
structures known
Saponins
Triterpenes
have 3
– Triterpenoid
x 10 = 30 carbons
– Steroidal
• Steroids are
• Steroids
derived from them;
– Misc.
steroidsto
lose
3 carbons
end
up with 27
– Phytosterols
– Cardiac glycosides
Triterpene skeleton
Steroid skeleton
Cardiac Glycosides in Lily of the Valley
• ~ 40 different
glycosides based on
several different
aglycones; variable
• Convallatoxin highly
active, but generally no
more than 10% of the
amount ingested can be
absorbed
• Positive inotropic effect;
used for mild cardiac
insufficiency
Tetraterpenes: Carotenes &
Xanthophylls
• Lycopene – parent compound of carotenoids
• Carotenes – alpha-, beta-, delta- & gammacarotenes are closely related
• Xanthophylls – carotenoids with oxygen in their
structures – include lutein, neoxanthin &
violaxanthin; capsanthin & capsorubin;
astaxanthin
Capsaicinoids: Pungent Principles in
Capsicum Annuum
• Capsaicin & relatives are oil-soluble
• Powerful topical analgesics: herpetic neuralgia, arthritis
• Diaphoretic, rubefacient, antiseptic
Betalain Alkaloids
• Nitrogenous pigments found only in a few
plant families, where they replace
anthocyanins
• Very potent antioxidants
• Anticarcinogenic
Betanidin
Pyrrolizidine Alkaloids (PAs)
Necine rings
Lycopsamine, a monoester
Necine rings are
metabolized into
toxic pyrroles in
the liver cells
Symphytine, a
diester
Isoquinoline Alkaloids in Mahonia
• Berberine & relatives predominate
• Some palmatine & jatrorrhizine
• Actions similar to Goldenseal
Berberine
Herbs for the Immune System
Supportive Science for Traditional Herbal Medicine
© Lisa Ganora 2008
Astragalus
• Stimulates nonspecific immunity
• Deep immune system
tonic
• Antioxidant
• Adjunct therapy for
cancer
• Astragaloside III is
one of many saponins
in the root
Astragaloside III
Popular Healing Herbs
Supportive Science for Traditional Herbal Medicine
© Lisa Ganora 2008
Cranberry
• Cranberries are rich in anthocyanins:
– Cyanidin glycosides
– Delphinidin glycosides
– Peonidin glycosides
• Contain glycosides of quercetin
• Lignans also present
• Proanthocyanidins inhibit binding of bacteria to
urinary tract epithelium
• Flavonoid extracts inhibit the growth of prostate
cancer cells
• Many constituents are antioxidant
Hawthorn
• Hyperin, a glycoside of quercetin,
is the main flavonoid in Hawthorn
• Also contains OPC’s
• Helps heart muscle to work more
efficiently, strengthens
contractions, stabilizes rhythm
• Enhances the utilization of
oxygen in cells
• Contains many antioxidants
• Antispasmodic, anti-inflammatory
Herbal Chemistry
Bonding in Phytochemicals
Acetone
Oxygen can form a double bond with carbon
Stereochemistry of Phytochemicals
R enantiomer
S enantiomer
X
Receptor binding site
X
Receptor binding site
Why isomerism matters: receptor specificity
Ring Systems
Cyclohexane ring vs. benzene ring
pH Affects Solubility: Bases
ToNext
isolate
compounds
thea lab,
first
thebasic
extract
is mixed in
with
water
And
the ionized
base,
being
water-soluble,
the
whole
plant
is
extracted
with
ethyl
solution
that has
been
acidified
with
partitions
intosolvent
thedilute
aqueous
acetate
or down
a similar
an inorganic
acid
like
HCl layer

similar documents