Daniela Istrati

Phyto-mediated nanostructured carriers based on dual vegetable actives involved in the prevention of cellular damage.

The growing scientific interest in exploitation of vegetable bioactives has raised a number of questions regarding their imminent presence in pharmaceutical formulations. This study intends to demonstrate that a dual combination between vegetable oil (e.g. thistle oil, safflower oil, sea buckthorn oil) and a carrot extract represents an optimal approach to formulate safe carrier systems that manifest cell regeneration effect and promising antioxidant and anti-inflammatory activity. Inclusion of both natural actives into lipid carriers imparted a strong negative charge on the nanocarrier surface (up to -45mV) and displayed average sizes of 70nm to 140nm. The entrapment efficiency of carrot extract into nanostructured carriers ranged between 78.3 and 88.3%. The in vitro release study has demonstrated that the entrapment of the extract represents a viable way for an equilibrated release of carotenoids. Besides the excellent antioxidant properties (e.g. scavenging up to 98% of the free oxygen radicals), the results of cellular integrity (e.g. cell viability of 133%) recommend these nanocarriers based on dual carrot extract-bioactive oil as a promising trend for the treatment of certain disorders in which oxidative stress plays a prominent role. In addition, the lipid nanocarriers based on safflower oil and sea buckthorn oil demonstrated an anti-inflammatory effect on LPS induced THP-1 macrophages, by inhibiting the secretion of two pro-inflammatory cytokines, IL-6 and TNF-α.

Naringenin improves the sunscreen performance of vegetable nanocarriers

The aim of this study was to evaluate the potential role of naringenin (NAR) in developing polyphenol-rich sunscreens by encapsulation into nanostructured lipid carriers (NLCs) based on vegetable oils. The functionality of NLCs loaded with NAR (NAR–NLC), NAR together with an UVA filter (NAR–UVA–NLC), and with an UVA filter (UVA–NLC) was evaluated by studying their photostability, UV protection factors, antioxidant activity and cytotoxic effect on L929 mouse fibroblasts. The photostability study revealed that NLCs loaded with NAR and/or the UVA filter were photostable under UV exposure. NAR–UVA–NLCs formulated into hydrogels exhibited the best photoprotection with an SPF of 8.4 and a UVAPF of 13.8, as compared with the same formulation without NAR which showed an SPF of 6 and a UVAPF of 10.5. The photoprotective values obtained for NAR–UVA–NLCs underline an efficient sunscreen performance, 87.5% of UVB radiation and 81.1% of UVA radiation being filtered. The antioxidant activity against short- and long-life radicals was also improved by co-loading NAR and a UVA filter into lipid nanocarriers. At low concentrations (25 and 50 μg mL−1) the nanocarriers showed no cytotoxicity and the presence of NAR inside the nanocarriers increased the cell viability. The in vitro drug release studies showed that the NLC system provides an increased release and permeation of NAR. All results indicated that NAR has the potential to be used in developing safer and efficient polyphenol-rich sunscreens, by improving the anti-UV and antioxidant performance of the vegetable nanocarriers.

Flash Vacuum Pyrolysis of 2,5-Diphenyloxazole

“C.D. Nenitzescu” - Institute of Organic Chemistry, Romanian Academy, Splaiul Independentei 202B,71141 Bucharest, RomaniaTel.: (401)-6383665, Fax: (401)-3121601, E-mail: draghici@ccoux.cco.roReceived: 28 January 2000; revised form 21 July 2000 / A ccepted: 1 August 2000 / Published: 9 A ugust 2000Abstract: FVP of the title oxazole (1) at 1000