The hexane extract of Echinops spinosissimus Turra subsp. spinosus flower heads was analyzed for its fatty acid and sterol composition. Its physicochemical characteristics were also studied. The saponification, iodine and peroxide values were determined as 255 mg KOH/g, 42.57 g I /100 g and 110 m equiv. O /kg of oil, respectively. The oleic (C18:1; 61.14%), palmitic (C16:0; 21.36%) and linoleic (C18:2; 10.45%) acids were the dominant fatty acids. This extract was also found to contain high levels of β-sitosterol and stigmasterol (44.97% and 34.95% of total sterols, respectively). On the other hand, the identification of terpenoid compounds was investigated by using GC/MS, which revealed fourteen major terpenoids mainly taraxasterol, lupeol, pseudotaraxasterol, lup-22(29)-en-3-yl acetate, taraxasteryl acetate, α-amyrin, β-amyrin, pseudotaraxasteryl acetate, hop-20(29)-en3-β-ol, α-amirenone, along with β-sitosterol and stigmasterol. Moreover, we have evaluated the in vitro antibacterial and antifungal activities of the unsaponifiable matter and a fraction isolated from this extract. These activities were conducted using the diffusion disc methods and broth microdilution assay. The resulted fraction from this extract showed the highest antibacterial activity with significant minimum inhibitory concentrations (MIC) values 125.0 μg/ml against Staphylococcus aureus, Micrococcus luteus and Bacillus cereus. However, it did exhibit no substantial antifungal activity.

This study has focused on the isolation of twenty-three halophilic actinomycetes from two ponds of different salinity and the evaluation of their ability to exert an antimicrobial activity against both their competitors and several other pathogens. From the 23 isolates, 18 strains showed antagonistic activity, while 19 showed activities against one or more of the seven pathogen strains tested. Six strains exhibited consistent antibacterial activity against Gram-negative and Gram-positive pathogens characterized at the physiological and molecular levels. These strains shared only 94-95% 16S rRNA sequence identity with the closely related species of the Thermoactinomycetaceae family. Among them, the potent strain SMBg3 was further characterized and assigned to a new genus in the family for which the name Paludifilum halophilum (DSM 102817 T ) is proposed. Sequential extraction of the antimicrobial compounds with ethyl acetate revealed that the crude extract from SMBg3 strain had inhibitory effect on the growth of the plant pathogen Agrobacterium tumefaciens and the human pathogens Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa. Based on the HRESI-MS spectral data, the cyclic lipopeptide Gramicidin S and four, and cyclo(L-Leu-L-Pro) were detected in the fermentation broth of Paludifilum halophilum. To our knowledge, this is the first report on the isolation of these compounds from members of the Thermoactinomycetaceae family.

A total of 54 halophilic strains were isolated from crystallizer TS18 (26 strains) and non-crystallizer M1 (28 strains) ponds and screened for their ability to produce protease, amylase, and lipase activities. Enzymatic assays allowed the selection of thirty-two active strains, among them, the ETR14 strain from TS18 showed maximum protease production yields and therefore, selected for further analysis. The results from 16S rRNA gene sequence analysis revealed that the strain belonged to Halorubrum ezzemoulense (Hrr. ezzemoulense) species. Further results indicated that optimum growth and protease production yields were obtained with 10-15% NaCl concentrations in the DSC-97 medium. The enzyme was also able to maintain high levels of protease activity at salt concentrations of up to 25%. While readily available carbon sources were noted to significantly reduce protease production, the combination between yeast extract and peptone enhanced protease excretion, which reached a maximum of 284 U ml(-1) at the end of the exponential growth phase. The enzyme exhibited optimum activity at pH 9 and 60 °C. The halophilic protease retained 87% of its initial activity after 1 h incubation at 70 °C and showed high stability over a wide range of pH, ranging from 7 to 10. This protease exhibited good temperature, pH, and salinity tolerance, which distinguishes it from other proteases previously described from other members of the holoarchaea genera and makes it a promising candidate for application in various industries.

Background Hypercholesterolemia is a major risk factor for the development of atherosclerosis and endothelial dysfunction. Methods The present study investigates the possible mechanism of Echinops spinosissimus Turra subsp. spinosus ( E. s. spinosus ) flower on the high cholesterol diet. Results Our in vitro results demonstrated the richness of E.s. spinosus flower in antioxidant compounds, and its antioxidant activities. The co-administration of E.s. spinosus (100 or 200 mg/kg/day) with high-fat diet attenuated hepatotoxicity as monitored by the improvement of oxidative stress biomarkers and plasma lipid and liver parameters, when compared to the hypercholesterolemic mice. Atherogenic index and body weight were also reduced markedly, compared to control mice. These results were confirmed by the improvement of histological changes and DNA damage. Conclusion These data indicate that E.s. spinosus flower reduces the hypercholesterolemia risk and atherogenic properties of dietary cholesterol. Its hypocholesterolemic effect may be due to its antioxidant activities and its richness in bioactive molecule.