PC&CA - Tool for Polyphenols Content Monitoring at the End of Spring Depending on Organic and/or Mineral Fertilization of Perennial Grassland

The present research proposed to use Principal Components & Classification Analysis (PC&CA) as tool for the polyphenols content monitoring of perennial forages, at the end of May 2008, from a Romanian grassland fertilized since 2003. The grassland soil was Calcic Luvisol. StatSoft-STATISTICA Version 10 performed the matrix correlation of PC&CA. The ten trials unfertilized or with different fertilization were the PC&CA cases. The active variables of PC&CA were the floristic composition components: Poaceae (GMay08%), Fabaceae (FMay08%), others botanical families group (OMay08%), Calamagrostis epigejos (Ce%), Festuca rupicola (Fr%), Lathyrus nissolia (Ln%), Lathyrus pratensis (Lp%), Filipendula vulgaris (Fv%) and Rosa canina (Rc%). Perennial forages polyphenols content at the end of May 2008 and mineral nitrogen fertilization data were supplementary variables. The correlation coefficient for total polyphenols content (PMay08) and others botanical families group (OMay08%) was positive: 0.704. In addition, the correlation coefficients of PMay08 and Fv% or Rc% were positively and higher than 0.700. Mineral nitrogen application influenced positively the Poaceae component (correlation coefficient - 0.915). The PC&CA can represent a helpful tool for polyphenols content monitoring of grassland perennial forages at the end of spring, depending on fertilization

Comparative researches on two direct transmethylation without prior extraction methods for fatty acids analysis in vegetal matrix with low fat content

<p>Abstract</p> <p>Background</p> <p>The aim of our work was to compare two methods, both based on direct transmethylation with different reagents, BF₃/MeOH (boron trifluoride in methanol) or HCl/MeOH (hydrochloride acid in methanol), in acid catalysis, without prior extraction, to find the fast, non-expensive but enough precise method for 9 principal fatty acids (lauric, myristic, palmitic, stearic, oleic, linoleic, linolenic, arahidic and behenic acids) analysis in vegetal matrix with low fat content (forage from grassland), for nutrition and agrochemical studies.</p> <p>Results</p> <p>Comparatively, between the average values obtained for all analysed fatty acids by the two methods based on direct transmethylation without prior extraction no significantly difference was identified (p > 0.05). The results of fatty acids for the same forage sample were more closely to their average value, being more homogenous for BF₃/MeOH than HCl/MeOH, because of the better accuracy and repeatability of this method. Method that uses BF₃/MeOH reagent produces small amounts of interfering compounds than the method using HCl/MeOH reagent, results reflected by the better statistical parameters.</p> <p>Conclusion</p> <p>The fast and non-expensive BF₃/methanol method was applied with good accuracy and sensitivity for the determination of free or combined fatty acids (saturated and unsaturated) in forage matrix with low fat content from grassland. Also, the final extract obtained by this method, poorer in interfering compounds, is safer to protect the injector and column from contamination with heavy or non-volatile compounds formed by transmethylation reactions.</p

Principal Components & Classification Analysis - Tool for Festuca rupicola Biodynamic Estimation Depending on Grassland Fertilisation

The grassland forage must be monitored related to the quantitative and qualitative parameters. Festuca rupicola is one of the grass desired in grassland forage. It is necessary to have accessible statistical tools to monitor the Festuca rupicola biodynamic. The objective of the present research was to study that multivariate analysis technique Principal Components & Classification Analysis (PC&CA) can be used as a statistical tool for the estimation of Festuca rupicola biodynamic dependent of the fertilisation. The experimental results for Festuca rupicola cutting were collected in June and August 2009 from a hill permanent grassland ecosystem, with a substances flow anthropic influenced by the application of mineral and organic (sheep manure) fertilisers. The hill permanent grassland was situated in Banat, Romania, on a Calcic Luvisol. It was selected eight trials as PC&CA cases, the Festuca rupicola biodynamic data as supplementary variables, and as active variables the fertilisation data and ecological soil parameters. The correlation coefficients of Festuca rupicola biodynamic parameters (Fr1 and Fr2) were positively in mineral fertilisation case and negatively for sheep manure application. The Festuca rupicola biodynamic in June 2009 was high positive correlated with the Festuca rupicola biodynamic in August 2009 (0.835). The statistical data performed in the present study have shown that the multivariate analysis technique PC&CA can be used as a statistical tool for the estimation of Festuca rupicola biodymamic dependent of the mineral and/or organic fertilisation of hill grassland ecosystem