Biogas, digested sludge and sludge liquor are the main products of anaerobic sludge digestion. Each of the products is influenced significantly by specific conditions of the digestion process. Therefore, any upgrade of the digestion technology must be considered with regard to quality changes in all products. Microaeration is one of the methods used for the improvement of biogas quality. Recently, microaeration has been proved to be a relatively simple and highly efficient biological method of sulfide removal in the anaerobic digestion of biosolids, but little attention has been paid to comparing the quality of digested sludge and sludge liquor in the anaerobic and microaerobic digestion and that is why this paper primarily deals with this area of research. The results of the long-term monitoring of digested sludge quality and sludge liquor quality in the anaerobic and microaerobic digesters suggest that products of both technologies are comparable. However, there are several parameters in which the 'microaerobic' products have a significantly better quality such as: sulfide (68% lower) and soluble chemical oxygen demand (COD) (33% lower) concentrations in the sludge liquor and the lower foaming potential of the digested sludge.

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Cancer treatment frequently carries side effects, therefore, the search for new selective and effective molecules is indispensable. Hymenaea courbaril L. has been used in traditional medicine in South America to treat several diseases, including prostate cancer. Leaves’ extracts from different polarities were evaluated using the 3-(4,5-methyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) cell viability assay to determine the cytotoxicity in prostate p53-null cells, followed by bio-guided fractionations to obtain the most cytotoxic fraction considering the selectivity index. The most cytotoxic fraction was analyzed by GC/MS to identify the active compounds. The majority compound, caryophyllene oxide, induced early and late apoptosis, depolarized the mitochondrial membrane, leading to several morphological changes and shifts in apoptotic proteins, and caspases were evidenced. Depolarization of the mitochondrial membrane releases the pro-apoptotic protein Bax from Bcl-xL. The apoptosis process is caspase-7 activation-dependent. Caryophyllene oxide is a safe anti-proliferative agent against PC-3 cells, inducing apoptosis with low toxicity towards normal cells.

Volatile organic silicon compounds (VOSiC) are harmful pollutants to the biota and ecological dynamics as well as biogas-based energy conversion systems. However, there is a lack of understanding regarding the...

In the present study concentration of heavy metals [HMs], such as Cu, As, Pb, Cr, Zn, Co, Cd and Ni, present in vegetables included in the typical Colombian diet were measured. The study was conducted as follows: samples of parsley, artichoke and carrots produced in a location near the Muña dam were collected, where the Bogot a River water is treated for use as a water resource. To determine food safety, national and international [HMs] established limits were compared with quantified [HMs] in samples of different vegetable parts and of the surrounding soil. Fresh samples were separated in their respective parts for cold acid digestion with HCl and HNO 3 (1:1) for 15 days. Heavy metal mean AE standard error (SE) were as follows (mg/kg) As 2.36 AE 0.185, Cd 0.16 AE 0.009, Co 0.43 AE 0.019, Cr 12.1 AE 0.453, Cu 13.1 AE 1.68, Ni 0.00, Pb 7.07 AE 0.482 and Zn 3.976 AE 0.332. Cd, Cr, As, Co and Ni showed high transfer factor in Cynara scolymus. Moreover, high Pb, Cu and Zn transfer factor were present in Petroselinum crispum. Except for Daucus carota roots, there was a high metal transfer specifically in Petroselinum crispum leaves and other different plant parts, with high transfer factor for Cr, As, Co, Pb, Cu and Zn.