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Anaerobic mono- (AmoD) and co-digestion (AcoD) of two-phase olive oil mill pomace (TPOP) and pig slurry (PS) at different ratios were studied in a semi-continuous stirred tank reactor (sCSTR) at mesophilic temperature (37 °C). The methane yields for AcoD experiments ranged from 150.9 to 274.3 L CH 4 kg VS −1 d −1 . The maximum chemical oxygen demand (COD) removal rate (59.60%) was achieved for TPOP/PS 80:20 w/w substrate composition at OLR 3.68 g VS L reactor −1 d −1 and 24 days HRT. Despite the energy production from food waste is not a new process, the industrial implementation and application continue to be a challenge. Hence, the present paper also reports on the economic feasibility study of a full scale anaerobic co-digestion plant to treat 7000 t year −1 and 1750 t year −1 of TPOP and PS, respectively. The results of this study are compared against a conventional PS mono-digestion plant. Net present values (NPV) and payback time periods (PBT) were reported to be 782,493 € and 135,701 € and 6.7 and 9.2 years for AcoD and AmoD plants, respectively. Finally, the sensibility analysis concluded that AcoD configuration is less dependent on energy and compost sale prices variations. [ABSTRACT FROM AUTHOR]

Due to the great importance of the olive sector in the Mediterranean area, it is necessary to develop an economical and environmentally friendly treatment for the valorisation of olive pomace. In the present study, an integrated valorisation scheme of two-phase olive pomace (TPOP) (main semi-solid by-product produced by two-phase centrifugation oil extraction systems) was assessed, where polyphenols were previously recovered in a high-value liquid extract to facilitate the subsequent continuous anaerobic digestion of dephenolised two-phase olive pomace (DTPOP). The average polyphenol extraction rate in this study was 55%, and the subsequent optimum methane production from DTPOP (416 ± 82 L CH4 kg VS−1 d−1) occurred at an Organic Loading Rate (OLR) of 2.89 ± 0.07 g VS L−1 d−1, and 24 days' Hydraulic Retention Time (HRT). Although energy production from food industry waste is not a new process, the industrial implementation and application continues to be a challenge. Hence, the present paper also reports on the economic feasibility study of an industrial-scale integrated plant to treat 8000 t TPOP y−1 from a medium-sized olive mill. The economic assessment showed that the combination of polyphenol extraction and the subsequent anaerobic digestion is an attractive treatment option. Net Present Value (NPV) and Internal Return Rate (IRR) were 1,493,234 and 12.8%, respectively, for an extract selling price of €680 t−1 (820 USD t−1). The sensitivity analysis concluded that variations in the selling price of polyphenol extracts and ethanol acquisition are the most significant factors that might influence the global economic viability of the integrated TPOP valorisation plant. • TPOP polyphenols can be recovered with low energy demand method. • The polyphenols chemical extraction yield was 55%. • The effect of dephenolized substrate over the methanogenesis is analysed. • Positive Net Present Value (NPV) at a discount rate of 5%. • Extract's sale and ethanol acquisition prices were key factors for profitability. [ABSTRACT FROM AUTHOR]

Abstract: Posttransplant diabetes mellitus (PTDM) occurs in approximately 15% to 20% of renal transplant patients. It has important clinical implications for graft function and survival. Anticalcineurin drugs are associated with an increased risk of developing PTDM. There is a little evidence that conversion from tacrolimus to cyclosporine (CsA)-based immunosuppression improves glucose metabolism and reverses diabetes. This prospective study included nine renal transplant patients (mean age of 34 ± 20) with PTDM under immunosuppression with tacrolimus. Five were switched directly to CsA and the other four (glycemia > 250 mg/dL) required insulin and were simultaneously switched to CsA. Basal blood levels of tacrolimus were 7.9 ± 1.9 ng/dL. Conversion was associated with an early, significant improvement of glycemia and HbA1c blood levels (P < .01). At the end of the follow-up, the glycemia (105 ± 20 mg/dL) and Hb1Ac (5.1 ± 0.4 mg/dL) were normal. Insulin was discontinued between 3 and 6 months in all patients who required it at the beginning. Cholesterol did not change significantly and triglycerides decreased significantly (basal 210 ± 85 mg/dL, at 12 months 125 ± 29, P < .01). Graft function was stable with a mean serum creatinine of 1.7 ± 0.2 mg/dL. CsA blood levels remained stable during all follow-up periods (P = NS). There were neither episodes of acute rejection nor secondary effects related to the medication. In summary, renal transplant patients receiving tacrolimus who develop PTDM may display better control of hyperglycemia by a switch to CsA. [Copyright &y& Elsevier]