Oxygenated C17 polyacetylene metabolites from Algerian Eryngium tricuspidatum L. roots: Structure and biological activity.

The secondary metabolite pattern of Eryngium tricuspidatum has been found to be dominated by C17 acetylene oxylipins, according to the chemistry reported in the literature for the genus Eryngium. Two new oxylipins, 11-acetoxy-falcarindiol (4) and 1,2-dihydro-11-acetoxy-falcarindiol (5) have been isolated, along with main related polyacetylenes 1-3 and the already known monoterpene aldehydes 6-10, from the petroleum ether extract of roots. The structure and the absolute configuration of compounds 4 and 5 have been determined by spectroscopic methods as well as by comparison with related known compounds. Polyacetylenes 1-4 inhibited significantly the in vitro growth of a series of cancer cell lines, ranging from 0.3 to 29 µM, whereas 5 was inactive.

Identification of a new small bioactive peptide from Lactobacillus gasseri supernatant.

Ten lactic acid bacteria (LAB) strains, previously isolated from human ileal biopsy of healthy volunteers, were screened for production and secretion of molecules having anti-bacterial and anti-biofilm activities. Because many recent reports indicate that LAB secreted molecules may exert immune-modulatory action, we also tested the effect on human intestinal HCT116 cells challenged with bacterial lipopolysaccharides. One of the Lactobacillus gasseri strains, SF1109, strongly inhibited: (1) Pseudomonas aeruginosa growth; (2) Escherichia coli biofilm production; (3) LPS induction of P-ERK1/2 in HCT116 cells, and was selected for further characterisation of the secreted active molecule. Cell-free supernatant of the L. gasseri SF1109 was analysed and one 1.3 kDa peptide has been characterised. Eight out twelve amino acids of this peptide were identified allowing the synthesis of an octa-peptide which still presented the mentioned activities.

Alcanivorax borkumensis produces an extracellular siderophore in iron-limitation condition maintaining the hydrocarbon-degradation efficiency.

Obligate marine hydrocarbonoclastic bacteria possess genetic and physiological features to use hydrocarbons as sole source of carbon and to compete for the uptake of nutrients in usually nutrient-depleted marine habitats. In the present work we have studied the siderophore-based iron uptake systems in Alcanivorax borkumensis SK2 and their functioning during biodegradation of an aliphatic hydrocarbon, tetradecane, under iron limitation conditions. The antiSMASH analysis of SK2 genome revealed the presence of two different putative operons of siderophore synthetases. Search for the predicted core structures indicated that one siderophore is clearly affiliated to the family of complex oligopeptidic siderophores possessing an Orn-Ser-Orn carboxyl motif whereas the second one is likely to belong to the family of SA (salicylic acid)-based siderophores. Analyzing the supernatant of SK2 culture, an extracellular siderophore was identified and its structure was resolved. Thus, along with the recently described membrane-associated amphiphilic tetrapeptidic siderophore amphibactin, strain SK2 additionally produces an extracellular type of iron-chelating molecule with structural similarity to pseudomonins. Comparative Q-PCR analysis of siderophore synthetases demonstrated their significant up-regulation in iron-depleted medium. Different expression patterns were recorded for two operons during the early and late exponential phases of growth, suggesting a different function of these two siderophores under iron-depleted conditions.

Effect of heat treatments on biomolecular profile of Sardinian apple cultivars.

Postharvest heat treatments (hot water or hot air treatment) may be applied to horticultural crops to control fungal diseases, insect infestation and to reduce chilling injury in cultivars susceptible to low storage temperatures. The present study investigated the influence of hot water (53 degrees C for 60s) and hot air treatment (38 degrees C for 24h) applied to two typical Sardinian apple varieties, cvs. Miali and Caddina, on the composition of the lipophilic extracts of the peel as well as on the antioxidant activity of ethanolic extracts of both peel and pulp. The lipophilic extracts of the peel of the two varieties were almost similar and resulted to be dominated by the presence of triterpenes being ursolic and oleanoic acids the main metabolites in both analysed fruits. The chemical analysis of the extracts obtained from the different heat-treated samples for each variety revealed no significant difference in the relative distribution of triterpene components with respect to untreated control samples. This strongly suggested that heat treatment does not affect the composition of terpene metabolite profile of the fruit peel. On the other hand, the antioxidant activity of the ethanolic extracts of the peel and the pulp of heat treated was significantly different from that of control In particular, on Caddina variety the antioxidant activity levels of the peel were consistently higher than in the pulp and were affected by storage conditions. Differently, on Miali variety the antioxidant activity of heat-treated samples was higher than control sample in both peel and pulp.

3-O-methylfunicone, from Penicillium pinophilum, is a selective inhibitor of breast cancer stem cells.

OBJECTIVES: Cancer stem cells make up a subpopulation of cells within tumours that drive tumour initiation, growth and recurrence. They are resistant to many current types of cancer treatment, causing failure of such therapeutic approaches, including chemotherapy and radiotherapy. In the study described here, anti-proliferative effects of 3-O-methylfunicone (OMF), a metabolite from Penicillium pinophilum, were investigated on human breast cancer MCF-7 cells and cancer stem cells selected as mammospheres derived from MCF-7s. MATERIALS AND METHODS: Stemness markers were analysed on isolated mammospheres showing positive expression of CD24, CD29, CD44, CD133, CD184 and CD338. Cell proliferation and apoptosis were analysed by flow cytometry and RT-PCR. Cell colony formation assays were performed to evaluate colony formation of mammospheres. RESULTS AND CONCLUSION: OMF treatment affected both MCF-7 and mammosphere growth, inducing apoptosis. In addition, OMF strongly reduced stemness markers and survivin, hTERT and Nanog-1 gene expression. Growth of colonies in soft-agar was significantly affected by OMF treatment, too. Lastly, we tested ability of MCF-7 cells to form mammospheres after treatment with OMF or cisplatin, demonstrating that OMF treatment resulted in drastic reduction in number of mammospheres. These results introduce OMF as an effective molecule in suppressing breast cancer stem cells.

3-O-Methylfunicone, a metabolite produced by Penicillium pinophilum, modulates ERK1/2 activity, affecting cell motility of human mesothelioma cells.

OBJECTIVES: 3-O-methylfunicone (OMF), a secondary metabolite produced by Penicillium pinophilum, affects cell proliferation and motility in a variety of human solid tumours. The aim of this study was to demonstrate whether OMF has the ability to arrest cell division and motility, in a human mesothelioma cell line. Malignant mesothelioma is an aggressive cancer that does not respond to standard therapies the cells of which are considered to be highly resistant to apoptosis. MATERIAL AND METHODS: Cell motility and invasion were measured using a modified Boyden chamber. Gene expression was examined by RT-PCR, while ERK1/2 was investigated by Western blot analysis. All experiments were also performed on primary cultures of mesothelial cells. RESULTS: The present study shows that OMF inhibited motility of the NCI mesothelioma cell line by modulating ERK signalling activity, and affected alphaVbeta5 integrin and MMP-2 expression, inducing marked downregulation at both mRNA and protein levels. Substantial downregulation of VEGF gene expression was also demonstrated. These effects were not observed in normal mesothelial cell cultures. CONCLUSION: OMF may have potential as a naturally derived anti-tumour drug for treatment of mesothelioma.

A new xenicane norditerpene from the Indian marine gorgonian Acanthogorgia turgida.

Chemical investigation of the liposoluble extract of the gorgonian Acanthogorgia turgida, from Indian coasts, led us to isolate a new xenicane-based norditerpene, isoacalycixeniolide-A (1), along with the known structurally related compounds 2-6. The structure of the norditerpene (1) was elucidated by spectral methods (mainly by NMR techniques), whereas the absolute stereochemistry was suggested by the application of circular dicroism methodology.

3-O-methylfunicone, a secondary metabolite produced by Penicillium pinophilum, induces growth arrest and apoptosis in HeLa cells.

3-O-Methylfunicone (OMF) is a secondary metabolite produced by the soil fungus Penicillium pinophilum which has cytostatic properties. The aim of this study was to investigate the mechanisms by which such properties are exerted, with special reference to any anti-proliferative and apoptotic potential, on HeLa cells. OMF treatment caused about 44% inhibition of cell growth after 24 h, and modifications in the tubulin fibre organization. In addition, a significant increase in p21 mRNA expression and a decrease in cyclin D1 and Cdk4 mRNA expression resulted at the same time. Apoptosis induction was demonstrated by the annexin V assay, cytofluorimetric analysis of the DNA content of the sub-G1 fraction and DNA laddering. Taken together, our data showed that the compound inhibits proliferation of HeLa cells by several mechanisms, such as disruption of tubulin fibres, cell cycle arrest and apoptosis induction. The capacity of the compound to affect the cell cycle and to modulate apoptosis is indicative of a potential for the development of a new agent for cancer chemotherapy.