Allium tripedale Trautv. belonging to the subgenus Nectaroscordum grows naturally in the mountainous areas of northwest Iran. Leaves have a very strong and somewhat unpleasant taste and are widely used by the local population as a spicy vegetable. Three new cysteine based compounds were identified in A. tripedale as the first examples of sulfur containing 1-butenyl derivatives in nature. The compounds have been described as o-phthaldialdehyde (OPA) derivatives and identified as (+)-S-(1-butenyl)-L-cysteine sulfoxide (homoisoalliin) and its gamma-glutamyl derivative as well as the gamma-glutamyl derivative of S-(1-butenyl)-L-cysteine (desoxyhomoisoalliin). These cysteine sulfoxides have been also found in Allium siculum Ucria. As volatile compounds, di-(1-butenyl)-disulfide and the cepaene-like compounds di-(1-S-sulfoxymethyl-butyl)-disulfide, 1-S-sulfoxymethyl-butyl-1'-S-sulfoxy-1-butenyl-butyl-disulfide and 1-S-sulfoxymethyl-butyl-1'-S-sulfoxybutyl-butyl-disulfide could be tentatively identified by various MS experiments. Primary products resulting from the alliinase reaction of homoisoalliin seem to be highly unstable and were rapidly converted to the volatile compounds listed above.

A new cysteine sulfoxide containing a pyridyl residue was identified in bulbs of Allium L. species belonging to the subgenus Melanocrommyum section Megaloprason. One of these species, Allium stipitatum, is widely used as a crop plant and in folk medicine in Central Asia. The new cysteine sulfoxide was identified as L-(+)-S-(2-pyridyl)-cysteine sulfoxide. Aside from this cysteine sulfoxide, several pyridyl compounds could be identified, which were formed out of cysteine sulfoxides by the action of alliinase. Found cysteine sulfoxides and their metabolites are chemically unstable; thus, the analysis is rather difficult. By combining high-performance liquid chromatography (HPLC), HPLC tandem mass spectrometry, NMR, IR, and photometric methods, full structure elucidation of the cysteine sulfoxide was possible. Alliinase reaction products were mainly determined by various MS techniques. The achieved results give new insights in the chemistry of Allium crop plants and are probably useful for chemotaxonomical classification of the subgenus Melanocrommyum.

Marasmin, which is especially known from the two South African species Tulbaghia alliacea and Tulbaghia violacea , but was also described for the garlic mushroom Marasmius alliaceus , is the precursor of the thiosulfinate marasmicin. Marasmicin has attracted considerable attention because of its antifungal and tuberculostatic activities. However, many Allium species of the subgenus Melanocrommyum, especially Allium suworowii , are also very rich in marasmin. A. suworowii revealed concentrations of marasmin up to 1.6%, related to the fresh weight of bulbs, and up to 3.0%, related to air-dried fruiting bodies, of the corresponding γ-glutamylmarsmin was found in M. alliaceus. Both species show much higher amounts of marasmin as Tulbaghia and could be considered as natural sources for the isolation of this compound. Further promising Allium species with considerable amounts of marasmin besides other cysteine sulfoxides are Allium stipitatum and Allium altissimum . (R(S),R(C))-Marasmin is typical for the investigated species of the subgenus Melanocrommyum, whereas γ-glutamyl-(S(S),R(C))-marasmin is the only cysteine sulfoxide for the genus Marasmius known until now. Both cysteine sulfoxides were isolated and described as o-phthaldialdehyde (OPA) derivatives. Furthermore, the cysteine sulfoxides methiin, propiin, S-(2-pyrrolyl)-cysteine sulfoxide, eventually S-(2-pyridyl)-cysteine sulfoxide and S-(2-pyridyl)-L-cysteine N-oxide were found.

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Spectral phase interference (SPI) has attracted considerable attention during last years as method for biomolecular interaction analysis (BIA). The advantages of this method are real time measurements independently from the refraction index of the investigated solution. Therefore, this method was applied for evaluating the influence of mouth rinsing solutions like chlorhexidine digluconate (CHX)-solutions on the pellicle formation upon a tooth model. The tooth model was a based glass chip, type 'K0'. The surface of this activated glass chip is comparable to the surface of the enamel of a tooth. After surface activation, saliva was applied in order to deposit a pellicle layer. The pellicle is the primary protein layer formed on the surface of a tooth. This layer has the function to prevent a direct contact of bacteria with the tooth surface. As a disadvantage, this layer is the docking point and primary nutrition reservoir for bacteria forming the plaque. Analysing the interaction of this bio layer with mouth rinsing solutions is essential to evaluate effects on the formation of plaque. In this investigation, evidences for positive effects of CHX-solutions and amino fluorides on the formation of the pellicle have been found. Treatment with these solutions resulted in a dose dependent enhanced thickness of the pellicle. It can be assumed, that these modified pellicle layers are more resistant against bacteria attack.