Radical scavenging activity is involved in aging processes, antiinflammatory, anticancer and wound healing activity. Hence, in the present study the DPPH radical scavenging activity of a natural product that possesses biological properties, an extract of Crocus sativus L. (saffron), grown in Crocos, Kozani (Greece), and some of its bioactive constituents (crocin, safranal) was studied. It was shown that a methanol extract of Crocus sativus exhibited high antioxidant activity, although it contains several active and inactive constituents. In trying to approximate a structure-activity relationship, two bioactive constituents of saffron extract were tested, namely crocin and safranal. Crocin showed high radical scavenging activity (50% and 65% for 500 and 1,000 ppm solution in methanol, respectively), followed by safranal (34% for 500 ppm solution). All the tested samples showed high radical scavenging activity, probably due to the ability to donate a hydrogen atom to the DPPH radical.Thus, saffron grown in Greece can be used promisingly in functional foods, drinks with antioxidant activity, in pharmaceutical and cosmetic preparations for their antioxidant activity and probably for their antiaging activity. Saffron can also be used internally in the form of powder or other pharmacotechnical formulae as a food supplement with antioxidant properties.

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Pistacia species contain oleoresins with bioactive triterpenes. In this study triterpenes, including minor components, were identified and quantified in both neutral and acidic fraction of Pistacia lentiscus var. Chia resin, grown exclusively in Chios island (Greece), collected traditionally, as well as by the use of stimulating agents (liquid collection). It was proved that these two resin samples were composed of several different minor triterpenes. In the traditional collection of the resin, 36 triterpenes were identified, 23 of which are new minor compounds (five in the acidic and eighteen in the neutral fraction). In the liquid collection resin eight compounds were identified in the acidic and 11 in the neutral fraction, while seven compounds were not contained in resin traditionally collected. The main triterpenes in both resin samples collected traditionally and by use of stimulating agents were in the following order: isomasticadienonic acid (24 and 22.5% w/w of triterpenic fraction respectively), masticadienonic acid (9.3 and 14.7% w/w of triterpenic fraction) and 28-norolean-17-en-3-one (19 and 36% w/w of triterpenic fraction respectively). The aim of this study was to compare the qualitative and quantitative composition of triterpenes in the resin samples collected using the traditional and new liquid techniques, and examine whether the collection technique influences the contained triterpenes in P. lentiscus var. Chia resin samples. Finally, since there is confusion on interpreting mass spectra of triterpenes we present an analytical review on the base peaks, main fragments and fragmentation mechanism/pattern of several skeleton penta- and tetra- cyclic triterpenes reported in P. lentiscus resin. Also, a biosynthetic route for triterpene skeletons contained in P. lentiscus resin was approached.

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The ability of pegylated liposomes (sterically stabilized liposomes-SSL) to localize in solid tumors via the enhanced permeability and retention (EPR) effect, partly depends on their long circulating properties which can be achieved by grafting polyethylene glycol (PEG) to the liposomes' surface. Alkannin and shikonin (A/S) are naturally occurring hydroxynaphthoquinones with a well-established spectrum of wound healing, antimicrobial, anti-inflammatory, antioxidant, and recently established antitumor activity. The purpose of this work was to prepare and characterize shikonin-loaded pegylated liposomes as a new drug carrier for shikonin, as a continuation of authors' previous work on conventional shikonin-loaded liposomal formulations. Three new pegylated liposomal formulations of shikonin (DSPC-PEG2000, EPC-PEG2000, and DPPC-PEG2000) were prepared and characterized in terms of physicochemical characteristics, pharmacokinetics, and stability (at 4 °C, for 28 d) and compared with the corresponding conventional ones. Particle size distribution, ζ-potential, entrapment efficiency, and release profile of the entrapped drug were measured. Results indicated the successful incorporation of shikonin into liposomes alongside with their good physicochemical characteristics, high entrapment efficiency, satisfactory in vitro release profile, and good physical stability. The results are considered promising and could be used as a road map for designing further in vivo experiments.