Characterization of an Alliin Lyase Preparation from Garlic (Allium sativum)

Abstract

An alliin lyase (EC 4.4.1.4) preparation from garlic, ALLIUM SATIVUM L., has been purified to apparent homogeneity. The purification procedure involved liquid chromatography steps on hydroxylapatite, on an anion exchanger, and on a chromatofocussing medium. The enzyme protein was characterized by a relative molecular mass of 108,000, and was found to consist of two equal subunits. Its isoelectric point was determined to be 4.9. The enzyme appeared rather thermolabile. Simulated gastric-intestinal passage by a modified "half change test" revealed a high acid lability of the active alliinase protein. K (m)-values for different substrates were in the mM range, and activating energies for the cleavage of different substrates could be determined. A maximal specific activity for synthetic alliin in the range of 490 micromoles per min and mg protein could be achieved at 33 degrees C. There are some significant differences in the characterization of the purified protein compared to results previously reported by others on this enzyme.

Effect of Cooking on Garlic (Allium sativum L.) Antiplatelet Activity and Thiosulfinates Content

“…In all three previous studies, extensively boiled uncrushed Allium tissues were used for the cooked treatment. Thus, the possibility remains that alliinase, which is thermolabile (25), was heat-inactivated before homogenization and, therefore, the active antithrombotic sulfur compounds (e.g., TSs) were never produced rather than being destroyed by the high temperatures.…”

“…In all three previous works, uncrushed Allium tissues were extensively boiled before juicing. Alliinase, required for the formation of antiaggregatory organosulfur compounds upon tissue disruption, is thermolabile (25). Therefore, it is highly likely that, because of alliinase heat inactivation during the boiling process, no antithrombotic compounds (e.g., TSs) were formed in the homogenates.…”

Antiplatelet Activity of <i>Allium ursinum</i> and <i>Allium sativum</i>

“…A proportion of 0.35-1.15% alliin (S-allyl-L -(+)-cysteinsulfoxide) was found in fresh garlic bulbs as well as the enzyme alliinase which degrades alliin to allicin (allyl-2-propenthiosulfinate). The latter decomposes to several volatile strongsmelling sulfur compounds, such as E-and Z-ajoene and vinyldithiines [9][10][11][12] .…”

Lectin and alliinase are the predominant proteins in nectar from leek (Allium porrum L.) flowers

“…Previous work has shown that the typical underground storage organs of both species contain lectin (Van Damme et al 1991a;Smeets et al 1994) and alliinase (Nock and Mazelis 1986;Jansen et al 1989;Landshuter et al 1994) as predominant proteins. At present, there is no logical explanation for the striking resemblance of the protein composition of the garlic and ramsons bulbs (which are specialized storage tissue) and leek nectar.…”

“…1). Since the M r of this polypeptide corresponds to that of the subunits of the alliinase from most Allium species ( (Nock and Mazelis 1986;Jansen et al 1989;Van Damme et al 1992b;Landshuter et al 1994;Lohmuller et al 1994;Rabinkov et al 1994), leek nectar was examined for alliin lyase activity. As shown in Table 1, a very high alliinase activity was measured suggesting that the alliinase is indeed, an abundant protein, in the leek nectar.…”