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Ribes nigrum L. (blackcurrant) leaf extracts, due to high levels of flavonols and anthocyanins, have been shown to exhibit beneficial effects in inflammatory diseases. However, whereas their traditional use has been investigated and validated in several models of inflammation and oxidative stress, the possible impact on skin disorders is still largely unknown. The purpose of this work was to elucidate the effects of R. nigrum leaf extract (RNLE) on keratinocyte-derived inflammatory mediators, elicited by a Th1 or Th2 cytokine milieu. HaCaT cells were challenged with TNF-α, either alone or in combination with the costimulatory cytokines IFN-γ or IL-4, and the release of proinflammatory cytokines and mediators (IL-8, IL-6, s-ICAM-1, and TSLP) was evaluated. The results showed that RNLE preferentially interferes with IFN-γ signaling, demonstrating only negligible activity on TNF-α or IL-4. This effect was attributed to flavonols, which might also account for the ability of RNLE to impair TNF-α/IL-4-induced TSLP release in a cAMP-independent manner. These results suggest that RNLE could have an antiallergic effect mediated in keratinocytes via mechanisms beyond histamine involvement. In conclusion, the discovery of RNLE preferential activity against IFN-γ-mediated inflammation suggests potential selectivity against Th1 type response and the possible use in Th1 inflammatory diseases.

The phospholipid molecular species and the main peptide molecules of wheat sprout hydroalcoholic extract have been fully characterized by normal-phase high performance liquid chromatography coupled online with positive electrospray ionization tandem mass spectrometry. The extract that resulted was rich in phospholipid molecular species formed by the combination of the two essential fatty acids (α-linoleic and α-linolenic). These species accounted for 51.7% of total phosphatidic acid, 47.3% of total phosphatidylethanolamine, 37.7% of total phosphatidylcholine, and 14.1% of total phosphatidylinositol. The last one showed the highest amounts of species containing palmitic acid, thus representing the most saturated phospholipid class. The extract was also shown to contain several peptide sequences with both potential antioxidant domains and interaction sites for phospholipids (i.e., H-Ala-Gly-Ser-Met-Met-Cys-NH2, H-Tyr-Met-Thr-Val-Val-Ala-Cys-NH2, etc.); this latter finding can have a highly positive impact on the poor peptides bioavailability. Because of the presence of essential fatty acids-rich phospholipids and bioactive peptides, wheat sprout hydroalcoholic extract can be considered a potential functional food ingredient.

Aim of the Study: Sun-dried rind of the immature fruit of Punica granatum L. (Punicaceae) (Pg) is presently used as a herbal formulation (OMARIA) in Orissa, India, for the therapy and prophylaxis of malaria. The aims of this study were (i) to assess in vitro the antiplasmodial activity of the methanolic extract, of a tannin enriched fraction and of compounds/metabolites of the antimalarial plant, (ii) to estimate the curative efficacy of the Pg extracts and (iii) to explore the mechanism of action of the antiplasmodial compounds. Urolithins, the ellagitannin metabolites, were also investigated for antiplasmodial activity., Materials and Methods: Chloroquine-susceptible (D10) and -resistant (W2) strains of Pf were used for in vitro studies and the rodent malaria model Plasmodium berghei-BALB/c mice was used for in vivo assessments. Recombinant plasmepsins 2 and 4 were used to investigate the interference of Pg compounds with the metabolism of haemoglobin by malaria parasites., Results: The Pg methanolic extract (Pg-MeOH) inhibited parasite growth in vitro with a IC(50) of 4.5 and 2.8 microg/ml, for D10 and W2 strain, respectively. The activity was found to be associated to the fraction enriched with tannins (Pg-FET, IC(50) 2.9 and 1.5 microg/ml) in which punicalagins (29.1%), punicalins, ellagic acid (13.4%) and its glycoside could be identified. Plasmepsin 2 was inhibited by Pg-MeOH extract and by Pg-FET (IC(50) 7.3 and 3.0 microg/ml), which could partly explain the antiparasitic effect. On the contrary, urolithins were inactive. Both Pg-MeOH extract and Pg-FET did not show any in vivo efficacy in the murine model., Conclusions: The in vitro studies support the use of Pg as antimalarial remedy. Possible explanations for the negative in vivo results are discussed.

Due to its liver toxicity, the medicinal use of germander (Teucrium chamaedrys L.) was banned in some countries. Nevertheless, alcoholic extracts are still permitted as flavour ingredients since they are fundamental in providing a bitter aromatic taste. Teucrin A represents the substance of major concern regarding the potential toxicity of germander. Hence, teucrin A represents the best analytical and toxicological marker of alcoholic extracts of T. chamaedrys. A sensitive high-performance liquid chromatography method to detect teucrin A in beverages is reported. Teucrin A was prepared by isolation from the plant extract using column chromatography and crystallization. The identity and purity (99%) were established by melting point, nuclear magnetic resonance and liquid chromatography-mass spectrometry. The high-performance liquid chromatography procedure was validated and its intra- and interday performance was established (relative standard deviation ⩽ 13% and error 10%). In-house validation was carried out by analysing samples of beverages not containing T. chamaedrys spiked with a range of concentrations of teucrin A. The limit of detection was 0.1 ppm and the limit of quantification was 0.3 ppm. Teucrin A accounted for about 70% of the neo-clerodane diterpenoids found in the total extract of a specimen of T. chamaedrys. The content (± standard deviation) in 18 batches of different geographical origin was 2338 ± 740 ppm, per cent coefficient of variation = 32, mini- mum-maximum = 999-3445 ppm. The mean level of teucrin A in 10 bottles of the same brand was 6.1 ± 0.8 ppm, per cent coefficient of variation = 12. In 10 different brands found on the Italian market, the content of teucrin A ranged from not detectable to 10 ppm. [ABSTRACT FROM AUTHOR]