Showing papers on "Allicin published in 1991"

Identification and HPLC quantitation of the sulfides and dialk(en)yl thiosulfinates in commercial garlic products

Abstract: The content of dialk(en)yl thiosulfinates, including allicin, and their degradation products has been determined by high performance liquid chromatography (HPLC), using the respective determined extinction coefficients, for a number of commercially available garlic products. Quantitation has been achieved for the thiosulfinates; diallyl, methyl allyl, and diethyl mono-, di-, tri-, tetra-, penta-, and hexasulfides; the vinyldithiins; and (E)- and (Z)-ajoene. The thiosulfinates were found to be released only from garlic cloves and garlic powder products. The vinyldithiins and ajoenes were found only in products containing garlic macerated in vegetable oil. The diallyl, methyl allyl, and dimethyl sulfide series were the exclusive constituents found in products containing the oil of steam-distilled garlic. Typical steam-distilled garlic oil products contained about the same amount of total sulfur compounds as total thiosulfinates released from freshly homogenized garlic cloves; however, oil-macerated products contained only 20% of that amount, while garlic powder products varied from 0 to 100%. Products containing garlic powder suspended in a a gel or garlic aged in aqueous alcohol did not contain detectable amounts of these non-ionic sulfur compounds. A comparison of several brands of each type of garlic product revealed a large range in content (4-fold for oil-macerates and 33-fold for steam-distilled garlic oils), indicating the importance of analysis before garlic products are used for clinical investigations or commercial distribution.

Antimicrobial effects of Allium sativum L. (garlic), Allium ampeloprasum L. (elephant garlic), and Allium cepa L. (onion), garlic compounds and commercial garlic supplement products

Abstract: Diallyl thiosulphinate (allicin), methyl allyl thiosulphinate, and allyl methyl thiosulphinate found in aqueous garlic clove and powder homogenates showed in vitro antibacterial and antifungal activities while garlic polar compounds, including alliin, did not. E/Z-ajoene, a minor but water-soluble transformation product of allicin found in vegetable oil-macerates of garlic, demonstrated anticandidal activity. Garlic showed greater antibacterial and antifungal activities than a number of onion types. Garlic and elephant garlic clove homogenates demonstrated similar activity. The anticandidal activities of commercially available garlic supplement products corresponded in general to the activities known for the chemical compounds found in the products.

HPLC analysis of allicin and other thiosulfinates in garlic clove homogenates.

Abstract: Reversed-phase high Performance liquid chromatography (C18-HPLC) was used to separate and quantitate all the detectable alkyl and alkenyl thiosulfinates, including configurational isomers, of garlic homogenates. Pure thiosulfinates were synthesized or isolated and identified by (1)H-NMR, and their extinction coefficients determined. Some configurational isomers required Separation by silica-HPLC. Five previously unreported thiosulfinates have been found, four of which contain the TRANS-1-propenyl group and increase several-fold to over half the content of allicin upon storage of garlic bulbs at 4 degrees C with a concomitant decrease in a gamma-glutamyl peptide. The variation in thiosulfinate yield between different countries, stores, bulbs, cloves, and storage times was investigated. A method for standardizing the quantitation of allicin yield from garlic is proposed and compared to other methods of allicin analysis.

Efficacy of aqueous extract of garlic & allicin in experimental shigellosis in rabbits.

Abstract: The aqueous extract of garlic (Allium sativum) and allicin both showed significant in vitro antibacterial activity against isolates of multiple drug-resistant Shigella dysenteriae 1, Sh. flexneri Y, Sh. sonnei and enterotoxigenic Escherichia coli. The minimum inhibitory concentrations of the aqueous extract and allicin against Sh. flexneri Y were 5 and 0.4 microliters/ml, respectively. The two agents also showed promising in vivo antibacterial activity against Sh. flexneri Y when tested in the rabbit model of experimental shigellosis, fully curing the infected rabbits within 3 days. On the contrary, 4 of the 5 rabbits in the control group died within 48 h. The rectal swab of rabbits of the experimental groups became free of the challenge bacteria on the second day of treatment. The antibacterial activity against the challenge strain was observed in the sera of the treated rabbits with 30-60 min of administration of the agents. The LD50 values of the aqueous extract and allicin in mice were 173.78 ml/kg and 204.17 microliters/kg of body weight, respectively. At the therapeutic dose, the two agents did not show any adverse effects on the standard biochemical profile of blood.

Inhibition of cholesterol biosynthesis by a water-soluble garlic extract in primary cultures of rat hepatocytes.

Abstract: Cultured rat hepatocytes continually synthesize cholesterol form radiolabeled acetate during a 24 h incubation period and export it, presumably as VLDL (very low density lipoprotein) to the culture medium. Mevastatin inhibits cholesterol biosynthesis by 90%. Incubation of the cultures with water-soluble extracts of garlic powder (Kwai, Sapec) diminish cholesterol biosynthesis (20-25%) as well as its export into the medium (30-35%). The IC50-value is 90 micrograms/ml. Between about 0.25 and 10 mg/ml the average maximal inhibition amounts to about 23%. Cytotoxicity of the extracts is apparent at concentrations above 125 mg/ml only. Pure alliin alone, or after incubation with alliinase (conversion to allicin) in concentrations corresponding to its content in the extracts does not exert any inhibition. Replacement of 14C-acetate by 14C-mevalonate omits the inhibitory effect. The activity of HMGCoA (hydroxymethylglutaryl-CoA) reductase is significantly reduced by garlic extracts at 50 micrograms/ml. At higher concentrations fatty acid synthetase, cholesterol 7 alpha-hydroxylase and cholesterol acyltransferase are slightly inhibited. Fatty acid synthetase is the only one of these enzymes which is inhibited by alliin at very high concentrations. These results demonstrate that water-soluble garlic extracts diminish hepatic cholesterol biosynthesis, thus contributing to the reduction of blood cholesterol. The main target site seems to be HMGCoA-reductase. The actual active principle(s) is still unknown. Alliin, however, does not seem to be of major significance.

[Formation of allicin from dried garlic (Allium sativum): a simple HPTLC method for simultaneous determination of allicin and ajoene in dried garlic and garlic preparations].

Abstract: In garlic (Allium sativum L.) the enzyme alliin lyase catalyzes the cleavage of alliin into allicin which reacts further to furnish ajoene. A simultaneous determination of allicin and ajoene is introduced which, in contrast to the determination of alliin only, allows for the testing of the activity of alliin lyase. It can be demonstrated that at a pH value of less than 3 the enzyme produces only small amounts of allicin. For this reason preparations from garlic should be administered only as enteric-coated formulations.

The effect of dietary garlic on the development of cardiovascular disease

Abstract: The medicinal properties of garlic were recognized by the Babylonians and by many later populations. Garlic can lower serum lipid levels in rats and can significantly reduce the severity of cholesterol-induced atherosclerosis in rabbits. Most studies on humans have shown garlic to reduce serum cholesterol levels. In addition to its hypolipidemic properties, garlic also has hypotensive, anticoagulant and fibrinolytic properties. Thus, it can affect several of the factors that contribute to the risk of coronary heart disease. At present, there is no unified standard description of garlic potency; such a standard is needed to compare data from different sources accurately. The principal chemical entities in garlic are diallyl disulfide (obtained on steam distillation), allicin (obtained by ethanol-water extraction) and alliin (obtained by extraction with cold ethanol). Alliin can rearrange to give ajoene, a compound with many of the pharmacological properties of garlic oil.

Effects of irradiation and storage on the flavor of garlic bulbs cv red

Abstract: The effects of 50 Gy gamma irradiation 30 days after harvest on the flavor of garlic bulbs cv “Red” during storage at room temperature for 300 days were evaluated. The contents of sulfur compounds and enzymatic pyruvate (EP) were determined by GLC and spectrophotometry as a measure of flavor intensity. Upon comparison of irradiated and nonirradiated bulbs no differences were observed in the contents of EP, cyclic disulfide compounds 144-1 + 144-11 (GLC-induced rearrangment products of allicin, the chief flavor component), and diallyl disulfide (DADS). At the end of the storage both samples showed a significant reduction in 144-1 + 144-11 and EP. On the contrary, DADS underwent an increase in both treatments.

Preparation of odorless garlic extract

Abstract: PURPOSE: To obtain an odorless garlic extract deodorized to a level insensible by a person having ordinary olfactory sense by adjusting a garlic extract liquid to a specific concentration, adding a specific amount of activated carbon to the extract, heating the mixture under stirring, removing the activated carbon and concentrating the liquid. CONSTITUTION: Raw garlic separated into individual scales is extracted with water under heating and refluxing in vacuum of 400-500mmHg and the obtained garlic extract liquid is adjusted to a Brix concentration of 15-30%. Activated carbon is added to the liquid in an amount of 1/(10-25), preferably 1/(17-20) pts.wt. based on 1 pts.wt. of the liquid having an allicin concentration of 1,000ppm and heated preferably at 70-80°C for 30-60min under stirring. After removing the activated carbon, the liquid is concentrated to obtain the objective extract. COPYRIGHT: (C)1993,JPO&Japio

Therapeutic aquatic animal and garlic products

Abstract: Products comprised from oils and/or derivatives and/or preparations derived from fish and/or other aquatic animals and oils and/or extracts and/or powders derived from mature or immature garlic including or excluding the garlic active principle Allicin are useful in lowering cholesterol and saturated fat levels in blood.

Parameters affecting allicin formation as a secondary metabolite by static cultures of Allium sativum

Abstract: [Development of allicin in garlic callus as affected by hormone, source of C, and N variation in the media was investigated.] Garlic (Allium sativum L.) bulb explants produced undifferentiated white globular callus when grown on MS medium having 2,4-dichlorophenoxy-acetic acid (2,4-D) and kinetin (Kn). Such callus when grown on medium having indole-3-yl-acetic acid (IAA) and/or Kn developed into the differentiating callus which had comparatively more allicin than that of undifferentiated callus. Effect of sucrose, NH4+/NO3- ratios and hormone concn. on growth and allicin development in the callus was investigated. There was a significant increase in allicin development in callus when grown for up to 4 wk on medium having: sucrose at 3 and 5% levels; NH4+ and NO3- ratios at 2:1 and 1:1; and Kn alone at a concn. of 0.5 mg l-1, which produced a tenfold increase in allicin content.

Drug composition of foot favus and middle sole for footgear

Abstract: PURPOSE:To obtain the title composition capable of retaining extremely high effects for long time and preventing bath of the malodor of allicin as its defecting property and the risk of burn from occurrence thereof by mixing a semi-solid material obtained by adding glycerol to allicin with sodium chloride. CONSTITUTION:Finely pulverized garlic is mixed with 95% ethanol and the mixture is subjected to filtration extraction at ambient temperature and glycerol is gradually added to the resultant allicin liquid at ambient temperature and then the residual ethanol is evaporated to provide allicin kept to a semi-solid state. Sodium chloride is added to allicin material obtained by finely mincing said semi-solid allicin to provide the drug composition for foot favus. The composition is incorporated into middle sole of footwear (preferably by proving a medicine layer between air transmissible layers of the middle pad). Foot favus can be treated without directly applying the composition to the lesion and by only inserting the middle sole into a footwear, and further favus being latent in the footwear can be also killed.