Nutrient sequestration potential of water primrose Ludwigia stolinefera (Guill. & Perr.) P.H. Raven: A strategy for restoring wetland eutrophication

The current work investigates the capacity of the water primrose (Ludwigia stolinefera) to sequester inorganic and organic nutrients in its biomass to restore eutrophic wetlands, besides its nutritive quality as fodder for animals. The nutrient elements and nutritive value of the water primrose were assessed seasonally in polluted and unpolluted watercourses. The water primrose plants’ highest biomass was attained during summer; then, it was significantly reduced till it reached its lowest value during winter. In the polluted canal, the plant root and shoot accumulated higher contents of all nutrient elements (except Na and Mg) rather than in the unpolluted Nile. They accumulated most investigated nutrients in the growing season during summer. The shoots accumulated higher contents of N, P, Ca, and Mg than the root, which accumulated higher concentrations of Na and K. Therefore, summer season is the ideal time to harvest water primrose for removing the maximum nutrients for restoring eutrophic watercourses. The aboveground tissues had the highest values of ether extract (EE) during spring and the highest crude fibers (CF) and total proteins (TP) during summer. In contrast, the belowground tissues had the lowest EE, CF, and TP during winter. In spring, autumn, and winter seasons, the protein content in the grazeable parts (shoots) of the water primrose was within the range, while in summer, it was higher than the minimum requirement for the maintenance of animals. There was a decrease in crude fibers and total proteins, while an increase in soluble carbohydrates content in the below- and above-ground tissues of water primrose under pollution stress. The total protein, lipids, and crude fibers of the aboveground parts of water primrose support this plant as a rough forage.     

Phytochemical characterization of potential nutraceutical ingredients from Evening Primrose oil (Oenothera biennis L.)

Evening Primrose oil (EPO) is a natural product extracted by cold-pressed from Oenothera biennis L. seeds. EPO is widely used as a dietary supplement from which beneficial effects have been reported in rheumatic and arthritic conditions, atopic dermatitis, psoriasis, premenstrual and menopausal syndrome, and diabetic neuropathy. The beneficial effects of EPO are thought to be due to its γ-linolenic acid content; in contrast, little effort has been expended to characterize the non-triglyceridic constituents of EPO. In order to evaluate its potential as source of functional food ingredients our aim in this work has been identified and quantified the different components of EPO by different techniques (GC–MS and HPLC). The lipid profile showed that oleic (7%), linoleic (74%) and γ-linolenic (9%) were the most abundance fatty acids. Unsaponifiable matter and subfractions were obtained by CEE/2568/91. Separation of the compounds under study was achieved giving a reasonable analysis time and good resolution. A yield (1.82–1.95%) of unsaponifiable matter was obtained and levels of saturated hydrocarbons (0.291.97 ± 14.85 mg) were noticed. β-Sitosterol (7952.00 ± 342.25 mg/kg oil) and campesterol (883.32 ± 0.45 mg/kg oil) were predominant in phytosterol fraction (9573 mg/kg oil), while tetracosanol (236.93 ± 2.32 mg/kg oil) and hexacosanol (289.92 ± 3.41 mg/kg oil) in linear aliphatic alcohol fraction (798.04 ± 5.66 mg/kg oil). In the phenolic fraction (55.49 ± 2.76 mg/kg oil), ferulic acid (25.23 ± 2.64 mg/kg oil) was the major component. From the results obtained, it can be suggested that the Evening Primrose oil can be considered an interesting alimentary source of substances of nutraceutical value.     

类群特异性PCR引物设计与评估

本文以真核藻类18SrDNA类群特异性PCR引物的设计与评估为例,详细介绍了如何利用Primrose等一系列程序设计类群特异性PCR引物并评估其敏感性与特异性,并对这一方法的优势与应用类群特异性PCR引物进行群落多样性分析需要注意的问题进行了讨论。