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This study aimed to evaluate the impact of self fermentation on methane production as biological pretreatment of olive mill wastewater (OMW). The self-fermentation was carried out at room temperature without mixing and at natural light cycle. The batch assays were performed at the influent substrate concentration of 36.7 g VS/l (OMW 100%), 18,4 g VS/l (OMW 50%) and 9.2 g VS/l (OMW 25%). The methane production was performed at 37°C in mixing condition. The results of methane production were compared with those obtained using untreated OMW. The results of this study showed that the self fermentation process is a very effective pretreatment to produce methane. Only the self-fermented samples have produced methane from undiluted OMW and a maximum cumulative methane production of 7583 ± 138 mlCH4/L and a yield of 246 ± 10 mlCH4/ gVS were obtained. A yield increase of +13.5% at OMW dilution of 50% was also achieved as compared to untreated OMW results. Interestingly, in the anaerobic digestion of untreated OMW, high hydrogen yields, with an average value of 46.8 ± 1.9 mlH2/gVS, were obtained. Moreover a depletion around 20% v/v of polyphenols was recorded for all experimental set. © 2016 ETA-Florence Renewable Energies.

Different process configurations for the energetic valorization of Ricotta Cheese Whey (RCW), a dairy byproduct, were investigated by mesophilic Anaerobic Digestion (AD) under continuous operation mode using a Mono-phase (MPR) and two Bi-phase (BPR1and BPR2) Continuous Stirred-Tank Reactors (CSTRs). The results showed an increase in CH4production (21,4%-17. 3%) and in CH4content in biogas (19%-4%), in BPR1and BPR2respectively, compared to MPR (9. 59±0. 54NLCH4/d; 56. 3±0. 65%CH4). Although in BPR1 first phase, it was found negligible H2production (BPR1=0. 07±0. 002NLH2/d; 1. 1±0. 4%H2; BPR2=3. 91±0. 50 NLH2/d; 39±2%H2), a methane production comparable to BPR2was achieved, showing that the fermentation processes that occurred in the first phase can increases the final production of CH4regardless of the metabolic pathway. Low H2production in BPR1 contrasts with the high acetic acid concentration detected (19. 30±1. 4 mM), suggesting the establishment of an alternative pathway, the homoacetogenesis, which consumes H2and CO2to produce acetic acid. In order to investigate the effect of phase separations in BPR1and BPR2, the microbial community composition was analyzed in methanogenic reactors by Fluorescent In Situ Hybridization (FISH) in terms of Eubacteria vs Archaea and, inside the acetotrophic methanogenic guild, for Methanosarcina vs Methanosaeta. FISH analysis reveal the predominance in BPR1of Methanosarcina (9,4% vs 16,5% of total acetotrophic Archaea), compared to Methanosaeta, which predominate in BPR2(8,4% vs 16. 8%). Performing an economic feasibility analysis, the energetic valorization of dairy wastewater was result sustainable and profitable, pursuing the biorefinery concept. © 2016 ETA-Florence Renewable Energies.

This study aimed to evaluate the impact of self fermentation on methane production as biological pretreatment of olive mill wastewater (OMW). The self-fermentation was carried out at room temperature without mixing and at natural light cycle. The batch assays were performed at the influent substrate concentration of 36.7 g VS/l (OMW 100%), 18,4 g VS/l (OMW 50%) and 9.2 g VS/l (OMW 25%). The methane production was performed at 37°C in mixing condition. The results of methane production were compared with those obtained using untreated OMW . The results of this study showed that the self fermentation process is a very effective pretreatment to produce methane. Only the self-fermented samples have produced methane from undiluted OMW and a maximum cumulative methane production of 7583 ± 138 mlCH4/L and a yield of 246 ± 10 mlCH4/ gVS were obtained. A yield increase of +13.5% at OMW dilution of 50% was also achieved as compared to untreated OMW results. Interestingly, in the anaerobic digestion of untreated OMW, high hydrogen yields, with an average value of 46.8 ± 1.9 mlH2/gVS, were obtained. Moreover a depletion around 20% v/v of polyphenols was recorded for all experimental set., Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 965-969

Hydrogen is a clean energy carrier having great potential as alternative fuel. Despite its well-established production, by chemical/electrochemical processes, bio-conversion of organic wastes to hydrogen could be a sustainable alternative since the afore-mentioned methods require a lot of energy. Anaerobic digestion to bio-methane is considered a winning strategy to transform wastes into energy with reduction of environmental issues. Chitin is the second most abundant polysaccharide after cellulose. Huge amounts of chitinous wastes, produced from seafood industry and fungal fermentation plants, represent source of pollution if improperly disposed. In this paper the feasibility to obtain hydrogen and methane in a two-phase anaerobic bio-process using raw chitin was investigated. After a preliminary aerobic pre-hydrolysis, carried out by the chitinolytic fungus Lecanicillium muscarium CCFEE 5003, H2, was obtained by dark fermentation and CH4, subsequently, by further digestion. For best productions, pre-hydrolysis was optimised by response surface methodology. Highest hydrogen (147 ml/1) and methane (7713 ml/1) levels were obtained after 24 days of dark fermentation and 83 days of digestion, respectively. However, best productivities were obtained at day 14 and 30 for H2, and CH4, respectively. This work is the first attempt to use raw chitin to obtain these biofuels by dark fermentation and anaerobic digestion.

Enrichment of activity sludge allowed to select a suitable microbial mixed culture able to grow on crude glycerol as the only carbon source, using a very simple synthetic medium without any extra nutrient supplements. Following to statistical optimisation, the selected pool was able to effectively convert crude glycerol into H2 and ethanol, both at a near¬stoichiometric yield. Subsequently, upscale tests were performed to validate the statistical model, and fed¬batch tests, in non¬sterile conditions, led to a three¬fold increase of ethanol production, thus reaching 26g/L, while producing up to 9L of H2. These results were obtained without the use of vitamin¬ and trace element solution, tryptone or yeast extract. Based on these findings it seems feasible to totally exclude the use of any synthetic medium for glycerol fermentation, through the co ¬fermentation with other waste/residual (organic) compounds, i.e. proteins and carbohydrates derived from the microalgae. In this way it might be possible to link 3rd generation biodiesel with H2 and ethanol production, while avoiding the competition with food feedstock and agricultural land use. Moreover, the valorisation of crude glycerol (converted into high¬ value products) might contribute to enhance the economic viability of microalgae feedstock and biofuels, which are, at the moment, still too costly to be commercialized., Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 713-716

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We studied whether DAP-kinase hypermethylation plays a role as a prognostic marker in patients with follicular lymphoma (FL). We found that DAP-kinase was frequently hypermethylated in bone marrow (BM) samples of 52 FL patients at diagnosis (71%) and identified patients with worse progression-free survival (p=0.06). In particular, patients with histologically proven BM infiltration and DAP-kinase hypermethylation had a poorer outcome (p=0.037). In a total of 170 BM samples obtained at diagnosis or during follow-up, DAP-kinase hypermethylation and the bcl2/IgH rearrangement gave concordant results in 67% of samples (48% both positive, 19% both negative). Both mrakers were independent predictors of the disease status (p0.001).

The interplay between genetic susceptibility and exposure to carcinogens has been shown to be involved in the etiology of many solid tumors. We studied the frequency and clinical correlates of polymorphisms resulting in deletions of two genes involved in the detoxification of potentially carcinogenic agents, glutathione S-transferase (GST)-M1 and GSTT1 in patients with Hodgkin's lymphoma (HL).The prevalence of gene deletions in 90 patients with HL was compared with a case-matched cohort of 176 normal blood donors. GST gene polymorphisms were studied using a multiplex PCR method, including the BCL2 gene as an internal control.Deletions of the GSTT1 gene were more frequent in cases compared with controls (28.9 versus 17.6%, P = 0.04), resulting in an increased risk for HL in individuals with the GSTT1-null genotype (odds risk, 1.9; 95% confidence interval 1.04-3.46). The GSTT1-null genotype particularly increased the HL risk in females aged45 years (odds risk 6.1, 95% confidence interval 1.6-23, P = 0.008). Correlating patient characteristics to genotype, we found an association between the GSTT1-null genotype and a limited stage of disease (I/IIA versus IIB-IV, 40.6 versus 19.6%, P = 0.047) and an erythrocyte sedimentation rate of50 mm/h (P = 0.02). Patients with at least one GST deletion (GSTM1- or GSTT1-) had a significant better disease-free survival when compared with those with undeleted GST genes (GSTM1+/GSTT1+; P = 0.012).The GSTT1-null genotype may increase the risk for HL and is associated with favorable prognostic factors, and the presence of at least one GST deletion indicates an improved disease-free survival.