Garlic & Health

The conclusions of the Garlic & Health project

A large collection of 300 garlic (Allium sativum L.) accessions, originating from the centre of its biodiversity, was established. A highly variable core collection of ca. 60 accessions was developed on the basis of AFLP fingerprinting and was characterized for traits like organo-sulphur content, flowering ability, etc.
A model was developed for garlic generative multiplication which can pave the way for true seed garlic breeding.
An efficient and reliable garlic genetic modification method was developed based on Agrobacterium tumefaciens. A large number of transgenic garlic plants were produced using this protocol.
A mass propagation system was developed to mass propagate elite garlic clones on basis of embryogenic cell suspensions.
Large environmental and genetic effects were found for garlic organo-sulphur composition. These effects were shown in in vitro, greenhouse and field experiments.
The presence of an allyl synthase enzyme was observed in garlic pointing at the possibility that a serine route for the production of S-alkenyl cysteine sulphoxides may exist.

In vitro studies showed that garlic organo-sulphur compounds failed to inhibit TNF-α mediated activitation of the nuclear transcription factor NF-κB. Consequently they do not reduce expression of adhesion molecules like ICAM-1 and E-selectin. However organo-sulphur compounds do inhibit LPS induced liberation of pro-inflammatory cytokines, like IL-1ß and TNF-α, resulting in a reduced NF-κB activity.
In vitro studies showed that DADS inhibited significantly hepatocellular cholesterol biosynthesis via the activation of an AMP-dependent kinase.
Different levels of garlic organo-sulphur content had quite different inhibitory effects on in vitro cholesterol biosynthesis.
Garlic powder originating from field-grown garlic cv. Printanor had no anti-inflammatory or anti-atherosclerotic effects on APOE*3 transgenic Leiden mice.
A human intervention study with a parallel double blind, double dummy design including 92 subjects showed no significant effects after up to 3 months for a large number of parameters involved in the initiation of atherosclerosis.

In vivo rat studies showed that organo-sulphur compounds can prevent hepatocarcinogenesis initiated by chemical carcinogens. This effect is partly due to a reduction of the genotoxicity of carcinogens and to the modulation of enzymes involved in activation and detoxification of genotoxic compounds. The efficacy is correlated with organo-sulphur content.
The metabolism of organo-sulphur compounds from garlic in rat has been partly elucidated.
A parallel double blind, double dummy design human intervention study including 92 subjects showed that parameters involved in the initiation of cancer were not significantly influenced during a period of three months.

A procedure was succesfully developed to enhance the shelf life of garlic tablets. The newly developed method involved the production of aqueous coated garlic tablets.
A new method was developed for the analysis of organo-sulphur compounds in garlic.