Garlic, absorption

Pale-yellow to dark-brown liquid with a faint odor like garlic. Odor becomes more pronounced during storage. This material is hazardous through inhalation, skin absorption (liquid), penetration through broken skin, and ingestion, and produces local skin/eye impacts. 

There are only a few reports on the absorption, metabolism, and excretion of garlic s sulfur compounds available. Further, until now it is not known what metabolic form of allicin actually reaches the target cells, and it is still unknown how garlic compounds might function in the body. 

Human clinical studies Allicin is well absorbed, as indicated by a persistent garlicky odor on the breath, skin, and amniotic fluid of persons after consumption of fresh garlic (83). Because oral comsumption of pure allicin has been shown to significantly increase overall body catabolism of triglycerides, a substantial absorption of allicin is assumed to occur (84). However, the metabolic fate of allicin in the body is not well understood. 

There is a general requirement for pyridoxal-5-phosphate (24, 25, 27, 44) although not all of the activity lost on dialysis is restored by adding the cofactor. This requirement explains the inhibition by hydroxylamine and hydrazine (24, 25). The reaction is a typical pyridoxal-5-phosphate catalyzed a,/ -elimination with a mechanism similar to serine dehydrase and cysteine desulfhydrase (45). The coenzyme is probably bound as a Schiff base with an amino group of the enzyme since there is an absorption maximum at 415 nm in solutions of the purified garlic enzyme (40). The inhibition by L-cysteine is presumably caused by formation of a thiazolidine with the coenzyme (46). Added pyridoxal-5-phosphate also combines directly with the substrate. The dissociation constant for the complex is about 5 X lO M. When this is taken into account, the dissociation constant of the holoenzyme can be shown to be about 5 X 10 M (47). The higher enzyme activity in pyrophosphate buflFer than in Tris or phosphate may be explained by pyrophosphate chelation of metal ions which otherwise form tighter complexes with the substrate and coenzyme (47). This decreases the availability of added coenzyme. 

Germylphosphine has an exceptionally strong odor (similar to garlic) and is undoubtedly very poisonous. The vapor pressure may be represented by the equation log Pmm = 7.277 — 1415.5/T (where T = kelvin). The extrapolated boiling point is 48.8°. The — 45° vapor pressure (chlorobenzene slush) is 12.0 torr and may be used as a criterion of purity.7 The infrared spectrum shows absorption... 

Colorless, neutral gas. Disagreeable garlic odor. Very poisonousl mp —117°. bp —62.5°. Dissociation pressure al 0 = 0.806 atm. Decomposes when heated at 300°, depositing arsenic which volatilizes at 400°. On exposure to light, moist arsine decomposes quickly depositing shiny black arsenic. Slightly sol in water. Aq solns are neutral. Traces are best removed by absorption in potassium permanganate soln or in bromine water. 

HEALTH SYMPTOMS inhalation (headache, sleepiness, garlic breath, nausea skin absorption (tremors, convulsions, respiratory arrest, central nervous system depression) ingestion (abdominal pain, nausea, vomiting, constipation, garlic odor of breath). 

Fenthion (0,0-dimethyl 0-[3-methyl-4-(methylthio)phenyl]phos-phorolhioale [CAS 55-38-9]) An organophosphate-type cholinesterase inhibitor (see p 291). Highly lipid soluble toxicity may be prolonged. Dermal absorption is rapid. 0.2 mg/m S Yellow to tan viscous liguid with a mild garlic-like odor. Vapor pressure is 0.00003 mm Hg at 20°C (68°E). 

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