Popular belief attributes to garlic a host of wondrous abilities, from fighting disease to keeping away vampires. Now Weizmann researchers have provided new evidence that this pungent-smelling plant really is good for us.
Raw garlic, it turns out, is an excellent, although smelly, natural broad-spectrum antimicrobial drug. And, among other beneficial effects, it may prevent cholesterol from clogging up the arteries.
Institute scientists were able to clarify how garlic works after developing a unique biotechnological procedure for producing large quantities of pure allicin, the main biologically active component of garlic and the one responsible for its smell.
Profs. David Mirelman and Meir Wilchek of the Institute?s Biological Chemistry Department headed the project, working with colleagues Drs. Serge Ankri, Talia Miron and Aharon Rabinkov, and with Prof. Lev Weiner and Dr. Leonid Konstantinovski of the Organic Chemistry Department.
The scientists discovered that allicin has the power to render dysentery-causing amoebas harmless. That's because allicin blocks two groups of enzymes without which amoebas cannot survive or invade and damage tissues. These types of enzymes are also present in a wide variety of infectious organisms, such as bacteria, fungi and viruses. Thus, by blocking the enzymes, allicin can ward off a wide range of infections. Allicin's role in fighting infection may be particularly valuable in light of the growing bacterial resistance to antibiotics.
The researchers found that allicin produces its blocking effect by reacting with molecules known as sulfhydryl groups. Sulfhydryl groups are among the essential elements of the enzymes found in infectious organisms, but they are also crucial components of other enzymes, some of which participate in the synthesis of cholesterol. Thus, by reacting with and modifying the sulfhydryl groups, allicin not only disables infectious organisms but also may help prevent the clogging of arteries.
Moreover, the researchers provided evidence that allicin can act as an antioxidant, gobbling up harmful oxygen molecules believed to contribute to atherosclerosis, tumor growth, aging and other processes.
Allicin, which in nature protects the garlic plant from soil parasites and fungi, is created when garlic cloves are crushed. Crushing causes two components of garlic, allicin and the enzyme alliinase, to interact. The biotechnological method developed at the Weizmann Institute makes it possible to produce semi-synthetic allicin.
A patent application for the production of allicin has been submitted by Yeda Research and Development Co. Ltd., the Institute's technology transfer arm, and several companies have already expressed interest in scaling up the process for clinical testing and commercial use.
Prof. Mirelman holds the Besen-Brender Chair of Microbiology and Parasitology, and Prof. Wilchek, the Marc R. Gutwirth Chair of Molecular Biology. This research was funded in part by the Center for Molecular Biology of Tropical Diseases at the Weizmann Institute; the Avicenne Program of the European Union; the Center for the Absorption of Scientists, Israel's Ministry of Absorption; and France's Foreign Ministry. Research facilities: Mrs. Ellen Epstein, Haifa, Israel; Mr. and Mrs. Sanford Diller, Los Angeles, California.