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Gentiana Lutea root (G. Lutea) is a medicinal herb, traditionally used as a bitter tonic in gastrointestinal ailments for improving the digestive system. The active principles of G. Lutea were found to be secoiridoid bitter compounds as well as many other active compounds causing the pharmacological effects. No study to date has yet determined the potential of G. Lutea antioxidant activity on lipid oxidation. Thus, the aim of this study was to evaluate the effects of an extract of G. Lutea on lipid oxidation during storage of an emulsion. G. Lutea extracts showed excellent antioxidant activity measured by DPPH scavenging assay and Trolox equivalent antioxidant capacity (TEAC) assays. An amount of 0.5% w/w G. Lutea lyophilise was able to inhibit lipid oxidation throughout storage (p < 0.05). A mixture of G. Lutea with 0.1% (w/w) BSA showed a good synergic effect and better antioxidant activity in the emulsion. Quantitative results of HPLC showed that G. Lutea contained secoiridoid-glycosides (gentiopiocroside and sweroside) and post column analysis displayed radical scavenging activity of G. Lutea extract towards the ABTS radical. The results from this study highlight the potential of G. Lutea as a food ingredient in the design of healthier food commodities

Next generation of waste management systems should apply product-oriented bioconversion processes that produce composts or biofertilisers of desired quality that can be sold in high priced markets such as horticulture. Natural acidification linked to nitrification can be promoted during composting. If nitrification is enhanced, suitable compost in terms of pH can be obtained for use in horticultural substrates. Green waste compost (GW) represents a potential suitable product for use in growing medium mixtures. However its low N provides very limited slow-release nitrogen fertilization for suitable plant growth; and GW should be composted with a complementary N-rich raw material such as the solid fraction of cattle slurry (SFCS). Therefore, it is important to determine how very different or extreme proportions of the two materials in the mixture can limit or otherwise affect the nitrification process. The objectives of this work were two-fold: (a) To assess the changes in chemical and physicochemical parameters during the prolonged composting of extreme mixtures of green waste (GW) and separated cattle slurry (SFCS) and the feasibility of using the composts as growing media. (b) To check for nitrification during composting in two different extreme mixtures of GW and SFCS and to describe the conditions under which this process can be maintained and its consequences. The physical and physicochemical properties of both composts obtained indicated that they were appropriate for use as ingredients in horticultural substrates. The nitrification process occurred in both mixtures in the medium-late thermophilic stage of the composting process. In particular, its feasibility has been demonstrated in the mixtures with a low N content. Nitrification led to the inversion of each mixture’s initial pH.

The EU is committed to encourage biological treatments of organic waste as an alternative to landfill and also to enhance organic matter recycling. When these wastes are composted, the composition of the initial raw materials is very important in order to obtain a good quality product. In this article, the mineral composition of the organic fraction obtained from source-sorted collection (SC) and the organic fraction mechanically separated (MS) from mass-collected municipal solid waste was evaluated. Also, the compositions of these 2 raw materials that are used in the current Spanish municipal solid waste biological treatment facilities were compared. The mineral elements analyzed were the total content of the heavy metals Zn, Cu, Ni, Cr, Pb and Cd, and the plant nutrients P, K, Na, Ca, Mg, Fe and Mn. The results obtained were expressed on dry matter basis and on mineral matter basis. Important differences were detected between SC and MS samples, on both dry and mineral matter basis. In general, nutrient contents are higher in SC than in MS, and heavy metal contents are significantly lower in SC. Our results also support the idea that the heavy metal migration from the non-compostable materials to the decomposable matrix takes place from the beginning of the process while both types of materials are in contact.

Compost stability and maturity can be assessed by many methods, differing in both sample preparation and produced information. The method proposed here is the chemical stability degree (SD) the origin of which can be related to the Klason method for lignin determination in wood and pulp. It allows determination of the stability of organic matter and nitrogen through resistant organic matter and non hydrolysable nitrogen determinations, in any kind of dry and ground sample. This method avoids the disadvantages related to the determinations conducted on wet sample, such as respirometries or self heating test, which are effected by the water content and the particle size. The SD has been applied to different raw organic materials as well as to composts of different origin, producing reliable results. The Pearson correlations of SD with other usual parameters that can inform on compost quality have been of interest, revealing its usefulness to determine compost stability.

Ten composting facilities (CF) treating source-sorted organic fraction of municipal solid waste (OF) were sampled to study the relationship between the bulk density and the composting process (CP) development. Hundred and fourteen samples from different stages of the CP were considered (organic fraction, initial mixture, final decomposition, final maturation and compost), including the reject materials coming from the densimetric table at postprocessing. Total organic matter (TOM), moisture content (MC), wet bulk density and dry basis (BDd) were determined. Significant differences were detected for MC, TOM and BDd between some stages of the CP. The BDd increased along the CP while TOM decreased. Correlation studies showed a significant negative relationship between TOM and bulk density, especially BDd, during the CP, as a result of the biological activity. Moreover, a clear relationship was also found between TOM and BDd in samples related to reject materials. The results indicate that bulk density could be a simple and useful tool to evaluate the CP, in addition to the others parameters commonly used. At the same time, BDd could be an easy way to infer TOM lost within rejects.

The aim of this research was to characterise samples of yard trimmings (YT) and recirculated yard trimmings (RYT) that are used to co-compost organic fraction of municipal solid waste (OFMSW) taken from 18 composting facilities in Catalonia (NE Spain), to determine their contribution in the composting process, and to highlight the advantages and disadvantages of reusing RYT. We found significant differences between the characteristics of the two materials. RYT had higher pH levels, electrical conductivity, and organic and ammonium nitrogen content than YT. Nutrient content also shows an increment from YT to RYT, and in the case of P and K, this variation can be attributed to an exogenous source rather than the relative concentration during the composting process. We also found significant differences in particle size distribution and bulk density. From the results, it can be assumed that RYT could be reused in the composting process if OFMSW, YT, and RYT are used in the correct quantities to balance the mixture but they cannot totally replace the features of YT.

Organic fraction (OF) from municipal solid waste (MSW) was sampled from several Spanish composting facilities just before the composting process began, considering the two groups of OF treated at the current time: OF from source sorted collection (SC) and OF from non-source sorted collection but selected in the plant by mechanical devices (MS). Moisture content (MC), pH, electric conductivity (EC), total organic matter (TOM), resistant organic matter (ROM), organic nitrogen (org-N), resistant organic nitrogen (nh-N), and soluble inorganic nitrogen (NH4+-N) were analysed from both samples. These parameters are significant in the composting process and have environmental implications. Most of the Spanish composting facilities treat MS from the MSW collected in mass. This study was carried out to assess and underline the variation in the composition of OF depending on the sorting system. Significant differences were detected between the two groups. SC showed higher values for MC, TOM, org-N than MS which resulted in the highest pH and EC values. No differences were detected for ROM and nh-N, indicating a similar degradable potential. Based on the results of this study, it is recommended that the composting process be carried out in a way that reflects the category of OF treated as well as considering the addition of yard trimmings to avoid leachates formation, balance the C/N ratio and improve aeration.

e a psi c u m a n n u u m plants under summer field conditions were grown in 17 cm plastic pots with different substrates: (1) Peat-Polystyrene (1:1) (v/v), (2) Composted Pine Bark, (3) Composted Grape Refuse-Olot s Volcanic Ashes (1:1) (v/v), and (4) Peat-Composted Pine Bark-Perlite (1:1:1) (v/v/v). Transpiration rate and stomatal resistance daily variation depended on irradiance and on substrate water contento Plants with one morning irrigation, 2 l/pot, showed stomatic symptoms of water deficit during the morning, in substrate (3), and in the afternoon in the other media. E.A. \rJ. % vol: (1) 22.7; (2) 21.8; (3) 8.0; and (4) 19.1 • Two more irrigations, 1 l/pot each, overcame restrictions of gaseous exchange in substrate (3), increasing ~anspiration rates and decreasing stomatal resistance substantially. Furthermore in _all substrates this three irrigation treatment extended, at least for one hour in the afternoon, the potential gaseous exchange in relation to irradiance assuming photosynthesis and stomatal resistance dependence of photon fluence rateo