Mastic water is a commercial flavouring obtained during the steam distillation of mastic resin (the resin of Pistacia lentiscus var. chia) for the production of mastic oil. The mastic water extracts were analysed by GC-MS. The major compounds identified were verbenone, α-terpineol, linalool and trans-pinocarveol. Overall the composition was found to be very different from that of mastic oil. Additional GC-MS revealed the enantiomeric ratio of the chiral constituents of mastic water. The antimicrobial activity of mastic water extract, as well as that of its major constituents, was examined against Escherichia coli, Staphylococcus aureus and Candida spp. including ATCC wild clinical and food-borne strains. Linalool and α-terpineol were found to be the most potent antimicrobial constituents. Finally the stability of mastic water at different temperatures was studied, showing no change in the GC-MS profile of the organic extract for a period of 4 months at storage temperatures up to 4 °C. © 2011 Elsevier Ltd. All rights reserved.

Malassezia yeasts are found on the skin of all humans and many warm-blooded animals. In vitro they have the ability to synthesize potent ligands (indolo[3,2-b]carbazole, malassezin and indirubin) of the aryl-hydrocarbon receptor (AhR; synonym: dioxin receptor) when the sweat contained l-tryptophan is used as the single nitrogen source. The production of these AhR-ligands has been associated with pathogenic strains of a certain Malassezia species (Malassezia furfur) but recent evidence shows that this property is widely distributed in almost all currently known Malassezia species. AhR is associated with carcinogenesis and the potential connection of these ubiquitous skin symbionts, and putative pathogens, with skin neoplasia should be evaluated mainly focusing on mechanisms related to the distinctive ability of the yeast to produce potent AhR ligands. Hypothesis: Synthesis of available pertinent data show a possible link between Malassezia produced AhR ligands and skin carcinogenesis, particularly of basal cell carcinoma (BCC).BCCs are almost exclusively observed in animal species colonized by Malassezia. In humans and animals there is overlapping in the skin regions colonized by this yeast and affected by BCC. The potent AhR ligands synthesized by pathogenic Malassezia strains could contribute to tumor promotion by: modification of the UV radiation carcinogenesis, alterations in the salvage/survival of initiated tumor cells, inhibition of cell senescence, interaction with vitamin D metabolism, promotion of immune tolerance and finally pro-carcinogenic modulation of cell cycle progression and apoptosis. © 2011 Elsevier Ltd.

Chios mastic gum, the resin obtained as an exudate from the trunk and branches of Pistacia lentiscus L var. chia, is used extensively as a constituent of herbal drugs or functional foods. The oral absorption of its major constituents still remains unclear. In the context of identifying the features of mastic gum that are responsible for either therapeutic effects or effects of nutritional value, a methodology based on high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (MS/MS) was developed and applied for the quantification of mastic gum triterpenic acids, 24Z-isomasticadienonic acid (IMNA), and 24Z-isomasticadienolic acid (IMLA) in mouse plasma. The specific compounds were selected based on their biological activity and potential against Helicobacter pylori. Concentrations were determined simultaneously in mouse plasma after oral administration of mastic gum or total mastic extract without polymer (TMEWP) in order to evaluate the role of the natural polymer, poly - myrcene, in the absorption process. Following TMEWP administration in mice, circulating IMNA and IMLA plasma levels were significantly higher (approximately 10-fold) in comparison to IMNA and IMLA plasma levels following total mastic gum administration (CMG), suggesting that the polymer plays a critical role in the absorption process. More specifically following TMEWP administration, Cmax plasma values were 3300±859ng/mL for IMNA and 163±58ng/mL for IMLA. In comparison, following CMG administration, Cmax plasma values were 329±57ng/mL for IMNA and 28±8ng/mL for IMLA. The methodological approaches presented in this study, along with the findings, offer valuable information on the availability of bioactive components following ingestion of mastic and facilitate the uses of mastic either as an ingredient of functional foods or as a herbal drug. © Georg Thieme Verlag KG Stuttgart - New York.