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491.
Black cohosh preparations are popular dietary supplements among women seeking alternative treatments for menopausal complaints. For decades, triterpene glycosides and phenolic acids have dominated the phytochemical and biomedical research on this plant. In this study, we provide evidence that black cohosh contains an unexpected and highly diverse group of secondary nitrogenous metabolites previously unknown to exist in this plant. Using a dereplication approach that combines accurate mass measurements, database searches and general knowledge of biosynthetic pathways of natural products, we identified or tentatively identified 73 nitrogen-containing metabolites, many of which are new natural products. The identified compounds belong to several structural groups including alkaloids, amides or esters of hydroxycinnamic acids and betains. Among the alkaloids, several classes such as guanidino alkaloids, isoquinolines and β-carbolines were identified. Fragmentation patterns for major compound classes are discussed, which provides a framework for the discovery of these compounds from other sources. Identification of alkaloids as a well-known group of bioactive natural products represents an important advance in better understanding of the pharmacological profile of black cohosh.  相似文献   
492.
Essential oil, isolated by hydrodistillation from Chenopodium botrys aerial parts, expressed significant bactericidal and fungicidal activity against selected strains of microorganisms.  相似文献   
493.
This work studied a relationship between HO-1/CO system and lipid peroxidation with consequent effects on liver functions and NOS-2. We focused on curcumin pretreatment in rat toxic model of d-galactosamine and lipopolysaccharide. Hepatocyte viability, lipid peroxidation, antioxidant status, ALT and AST were evaluated. HO-1 and NOS-2 expressions and respective enzyme activity were determined. Curcumin caused decreases in ALT and AST levels as well as in lipid peroxidation. Furthermore, curcumin pretreatment increased liver HO-1 (2.4-fold, p = 0.001), but reduced NOS-2 (4.1-fold, p = 0.01) expressions. In conclusion, the tuning of CO/NO pathways is important in shedding light on curcumin's cytoprotective effects in this model.  相似文献   
494.
The essential oil from the aerial parts of Seseli annuum, wild-growing in Serbia, was obtained by hydrodistillation and analyzed using GC and GC/MS. A total of 43 components were identified representing 96.5% of S. annuum oil. The most abundant compounds were germacrene D (29.8%), sabinene (10.3%), beta-ocimene Z (9.8%) and limonene (8.6%). The essential oil showed antifungal activity against fifteen fungi with MICs between 12.5 to 50 microl/ml.  相似文献   
495.
Eight aphid species were determined as new records for Serbia as a result of the evaluation of the specimens caught by yellow water traps used for monitoring vector activities in seed potato crops during the 4 years 2007–2010. The invasive aphid species Macrosiphum albifrons Essig 1911; and the new species Acyrthosiphon cyparissiae (Koch 1855), Ctenocallis setosus (Kaltenbach 1846), Myzodium modestum (Hottes 1926), Myzocallis castanicola Baker 1917, Myzocallis occidentalis Remaudiè et Nieto Nafria 1974, Tinocallis platani (Kaltenbach 1843) and Wahlgreniella ossiannilssoni Hille Ris Lambers 1949. M. modestum is very difficult to detect, as it lives hidden in moss. All species are presented with characteristic morphological information of alatae and line drawings.  相似文献   
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In a two-year survey (2011–2012), 3220 samples were collected and analyzed in order to determine the presence and distribution of viruses in tomato crops at 56 localities of 18 districts in Serbia. Out of 12 viruses tested, Cucumber mosaic virus (CMV), Potato virus Y (PVY), Alfalfa mosaic virus (AMV), Tomato spotted wilt virus (TSWV), Tomato mosaic virus (ToMV) and Tobacco mosaic virus (TMV) were detected in 42.1, 40, 11, 8.6, 2.3 and 1.3% of the total tested samples, respectively. The results revealed that CMV was prevalent in 2011 and PVY in 2012. CMV and PVY, apart from being predominant, were also the most widespread viruses. In general, single infections were the most frequent type of infection. Additionally, the most common mixed infections were double infections and the most prevalent combination was CMV and PVY. In 2011, the incidence of diseases and the percentage of all infection types were significantly higher than in 2012. Furthermore, in 2011, regardless of total single infections being prevalent compared to mixed infections, two prevailing viruses were commonly detected in mixed infections. The additional molecular testing of ELISA-negative samples using virus specific primers did not reveal the presence of Pepino mosaic virus (PepMV), Tomato yellow leaf curl virus (TYLC), Tomato infections chlorosis virus (TICV) and Tomato chlorosis virus (ToCV).  相似文献   
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