Allyl Sulfur Phytochemicals Flashcards
Allyl sulfur phytochemicals
Major type is allyl sulfides
Potential health effects - used in folklore
Allium veggies: allicae family of plants
- garlic, onion, leeks, scallions, chives
Most research in garlic
History of garlic use
Considered one of the best disease preventing foods
Potency acknowledged for more than 5000 years
- used in past for immunity but hard to measure bioavailability for immunity
- also used to topically treat wounds in war
Phytochemistry of garlic
Likely developed as a plant protective mechanism against external influences
Key is SULFUR
- responsible for odour
- focusing on LIPID soluble (80%)
Phytochemicals formed from parent sulfur containing compound called GAMMA-GLUTAMYL CYSTEINE
Lipid soluble sulfur compounds in garlic
Stable compound: Alliin
After disruption, an alliinase converts alliin to allicin
Allicin is unstable and rearranges to breakdown products which are then absorbed
- DAS (diallyl sulfide)
- DADS (diallyl disulfide)
- DATS (diallyl trisulfide)
- ajoene
“Will be present in biological fluids therefore good biomarker”
Key enzyme: alliinase
Separate from alliin within the plant
Comes into contact with alliin following crushing, chewing, etc like glucosinolates
Converts alliin to Allicin very fast
- which then makes breakdown products
Alliinase is susceptible to HEAT
heat will reduce alliinase activity
- less Allicin produced, less breakdown products
Baked whole garlic will have no breakdown products
Chopped garlic before cooking can have breakdown products as the conversions are fast
Alliinase is susceptible to ACID
Gastric acid will denature alliinase
If undisputed garlic is swallowed then
- less Allicin produced, less breakdown products
- but we don’t swallow whole garlic
Implications for supplements?
Allyl sulfide health benefits
Garlic sulfur compounds have been researched for:
- anti microbrial/immunity
- cancer
- CVD
Allicin breakdown products most studies (DAS, DADS, DATS, ajoene)
Anti microbial/ immunity
Garlic historically used as antibiotic
DAS and DADS have shown dose dependent decrease in proliferation of H pylori, related to gastric ulcers
Topical ajoene comparable to pharmaceutical trestmeant in dermatitis
Ajoene suppresses fungal growth
Cancer effects: cancer cell growth
Growth of cancer cells inhibited by DADS in vitro
Water soluble SAC not as effective as lipid soluble component
- lipid soluble much more effective; suppress proliferation
Allyl sulfides also inhibit cancer cell proliferation
Cancer effects: phase one and two enzymes
Allyl sulfur compounds from garlic
- minimal effect on phase one enzymes
- increase activity of phase two enzymes (GST)
GOOD
CVD effects
Decreases total cholesterol
Decreases LDL cholesterol
Inhibits platelet aggregation
Garlic phytochemicals bioavailability
As always, bioavailability is core
Measurement of Allicin breakdown products in blood or urine has been challenging analytically
Detection of breakdown products in BREATH has revealed some info about bioavailability
- interesting biomarker of intake
Fresh garlic vs supplement
Relates to bioavailability
We know Allicin is produced with chewing or crushing garlic
But we don’t chew a supplement ( alliin can’t come into contact with alliinase) and the stomach acid denatures alliinase
Need to protect alliinase from gastric acids in supplements
- most supplements are enteric coated: cellulose or poly acrylic acid esters that are acid resistant and readily dissolve at neutral pH
Supplements are standardized for Allicin potential
Garlic and drug interactions
Shown to enhance the effects of anti coagulant meds (warfarin)
Shown to reduce the efficacy of anti AIDS meds (saquinavir)
This relates to safety considerations
Also being used with Covid
