Low-carbon wastewater treatment and resource recovery of recirculating aquaculture system by immobilized chlorella vulgaris based on machine learning optimization.

Immobilized microalgae biotechnologies can conserve water and space by low-carbon wastewater treatment and resource recovery in a recirculating aquaculture system (RAS). However, technical process parameters have been unoptimized considering the mutual interaction between factors. In this study, machine learning optimized the parameters of alginate-immobilized Chlorella vulgaris (C. vulgaris), that is, 474 µmol/(m2·s) of light intensity, 23 × 106 cells/mL for initial cell number, and 2.07 mm particle size. Importantly, under continuous illumination, the immobilized C. vulgaris and microalgal-bacterial consortium improved water purification and biomass reutilization. Transcriptomics of C. vulgaris showed enhanced nitrogen removal by increasing pyridine nucleotide and lipid accumulation via enhanced triacylglycerol synthesis. Symbiotic bacteria upregulated genes for nitrate reduction and organic matter degradation, which stimulated biomass accumulation through CO2 fixation and starch synthesis. The recoverable microalgae (1.94 g/L biomass, 47 % protein, 26.23 % lipids), struvite (64.79 % phosphorus), and alginate (79.52 %) every two weeks demonstrates a low-carbon resource recovery in RAS.

A Network of Processes for Biorefining Burdock Seeds and Roots.

In this work, a novel sustainable approach was proposed for the integral valorisation of Arctium lappa (burdock) seeds and roots. Firstly, a preliminary recovery of bioactive compounds, including unsaturated fatty acids, was performed. Then, simple sugars (i.e., fructose and sucrose) and phenolic compounds were extracted by using compressed fluids (supercritical CO2 and propane). Consequently, a complete characterisation of raw biomass and extraction residues was carried out to determine the starting chemical composition in terms of residual lipids, proteins, hemicellulose, cellulose, lignin, and ash content. Subsequently, three alternative ways to utilise extraction residues were proposed and successfully tested: (i) enzymatic hydrolysis operated by Cellulases (Thricoderma resei) of raw and residual biomass to glucose, (ii) direct ethanolysis to produce ethyl levulinate; and (iii) pyrolysis to obtain biochar to be used as supports for the synthesis of sulfonated magnetic iron-carbon catalysts (Fe-SMCC) to be applied in the dehydration of fructose for the synthesis of 5-hydroxymethylfurfural (5-HMF). The development of these advanced approaches enabled the full utilisation of this resource through the production of fine chemicals and value-added compounds in line with the principles of the circular economy.

A new simpler and reliable method for determining mineral oil in sewage sludge: Influence of biogenic compounds for the quantitative analysis of C10-C40 hydrocarbons.

The characterization of organic contaminants in sewage sludge is a fundamental step to address the relevant most appropriate management practice. In this perspective, C10-C40 hydrocarbon content was considered in Italy a crucial parameter to be considered, in spite of its irrelevance in the literature. The very complex mixture of organic substances of both biogenic and anthropogenic origin the sludge is made up of makes sewage sludge a matrix of uniqueness nature, and the analytic determination of hydrocarbon content through conventional procedures may be subjected to overestimation. In this work, optimization of two conventional protocols for the determination of mineral oil (EN14039 and IRSA CNR gravimetric method) were run with attention to anthropogenic compounds potentially affecting the C10-C40 mineral hydrocarbons determination. Effects from the first manipulations of sewage sludge samples to extraction procedure and clean-up operations were investigated. A new simple procedure was set up and tested on 30 samples from different wastewater treatment plants (WWTPs). Through a simple extraction with hexane (12 mL per 2 g of dried sludge, acidified with HCl conc.) at room temperature for 2 h, followed by a clean-up on Florisil column (10 mL-2 g) a confident determination of C10-C40 were obtained with respect to conventional optimized procedures. Variability within the range 0.06-9.49% was calculated with respect to the average value determined using three different methods, with an average value of 2.48 ± 2.37%, demonstrating the robustness of the determination. Up to 3% of the total hydrocarbons were identified as naturally occurring, namely terpenes, squalenes and deoxygenized sterols, passed through the clean-up Florisil column. A significant incidence (up to 75%) of the final overall C10-C40 content was found to be related to the C10-C20 component, originally present in the commercial polyelectrolytes in emulsion, widely used for conditioning before mechanical dewatering.

Cinnamomum zeylanicum Blume Essential Oil Inhibits Metastatic Melanoma Cell Proliferation by Triggering an Incomplete Tumour Cell Stress Response.

Given the known pro-oxidant status of tumour cells, the development of anti-proliferative strategies focuses on products with both anti- and pro-oxidant properties that can enhance antitumour drug cytotoxicity. We used a C. zeylanicum essential oil (CINN-EO) and assessed its effect on a human metastatic melanoma cell line (M14). Human PBMCs and MDMs from healthy donors were used as normal control cells. CINN-EO induced cell growth inhibition, cell cycle perturbation, ROS and Fe(II) increases, and mitochondrial membrane depolarization. To assess whether CINN-EO could affect the stress response, we analysed iron metabolism and stress response gene expression. CINN-EO increased HMOX1, FTH1, SLC7A11, DGKK, and GSR expression but repressed OXR1, SOD3, Tf, and TfR1 expression. HMOX1, Fe(II), and ROS increases are associated with ferroptosis, which can be reversed by SnPPIX, an HMOX1 inhibitor. Indeed, our data demonstrated that SnPPIX significantly attenuated the inhibition of cell proliferation, suggesting that the inhibition of cell proliferation induced by CINN-EO could be related to ferroptosis. Concurrent treatment with CINN-EO enhanced the anti-melanoma effect of two conventional antineoplastic drugs: the mitochondria-targeting tamoxifen and the anti-BRAF dabrafenib. We demonstrate that CINN-EO-mediated induction of an incomplete stress response specifically in cancer cells affects the proliferation of melanoma cells and can enhance drug cytotoxicity.

Operation of a pilot-scale lipid accumulation technology employing parameters to select Microthrix parvicella for biodiesel production from wastewater.

Wastewater treatment plants (WWTPs) may play a crucial role in shifting to a zero-emission future by becoming more sustainable and contributing to the circular economy (CE). Recovered lipids from urban sewage can serve as a raw material for biofuel production contributing to a waste reduction, mitigation of natural resources depletion and reinforcing security and energy independence. A novel, pilot-scale lipid accumulation technology (LAT) employing parameters to select M. parvicella for the biofuel/biodiesel production was implemented on a side stream of an urban WWTP. The LAT proved its concept as the average amount of extracted lipids accumulated in the bioreactors was three-fold higher when compared to the lipids existing in activated sludge. The average transesterification of extracted lipids to biodiesel resulted in a 1.6 % yield, meaning that from 1 kg of dried sludge, 16 g of biodiesel could be formed. The biodiesel produced complies with European standard specifications (EN14214).

A novel cascade biorefinery approach to transform food waste into valuable chemicals and biogas through thermal pretreatment integration.

A novel biorefinery platform integrating thermal pretreatment and solid-liquid separation unit is here proposed to fully exploit food waste (FW) potential for production of valuable chemicals and energy through semi-continuous anaerobic bioconversion. The liquid fraction deriving from raw or pretreated FW, was fermented into volatile fatty acids (VFAs, from acetic to caproic acid) while the residual fraction was converted into biomethane. Thermal pretreatment effectively extracted a portion of the macromolecular organics, especially starch, to the liquid phase, promoting acidogenic fermentation and chain elongation pathways (0.43 gVFA g-1VSfed and 0.58 gVFA g-1VSfed with raw and pretreated extract, respectively). In parallel, anaerobic digestion of solid residue in 10 L reactors showed process stability and higher conversion rate for the pretreated residue (0.31 against 0.26 Nm3CH4 kg-1VSfed). The mass-transfer balance coupled with the economic assessment, calculated in terms of direct gross added value, indicated promising revenues by integrating the thermal upstream treatment.

Pilot scale cellulose recovery from sewage sludge and reuse in building and construction material.

The recovery of cellulose in toilet paper from municipal wastewater is one of the most innovative actions in the circular economy context. In fact, fibres could address possible new uses in the building sector as reinforcing components in binder-based materials. In this paper, rotating belt filters were tested to enhance the recovery of sludge rich in cellulose fibres for possible valorisation in construction applications. Recovered cellulosic material reached value up to 26.6 gm-3 with maximum solids removal of 74%. Content of cellulose, hemicellulose and lignin was found averagely equal to 87% of the total composition. Predictive equation of cellulosic material was further obtained. The addition of recovered cellulose fibres in mortars bring benefits in terms of lightness, microstructure and moisture buffering value (0.17 g/m2%UR). Concerning mechanical properties, flexural strength was improved with the addition of 20% of recovered cellulose fibres. In addition, a simplified economic assessment was reported for two possible pre-mixed blends with 5% and 20% of recovered fibres content.

Variability of food waste chemical composition: Impact of thermal pre-treatment on lignocellulosic matrix and anaerobic biodegradability.

A comprehensive sustainable Food Waste (FW) management is globally needed in order to reduce the environmental pollution and the financial costs due to FW disposal; anaerobic digestion is considered as one of the best environmental-friendly alternatives to this aim. A deep investigation of the chemical composition of different Food waste types (cooked kitchen waste (CKW), fruit and vegetable scraps (FVS) and organic fraction of municipal solid waste (OFMSW)) is here reported, in order to evaluate their relevant substance-specific properties and their impact on anaerobic biodegradability by means of a sophisticated automatic batch test system. Suitability for a mild thermal pre-treatment (T = 134 °C and p = 3.2 bar) to enhance the biological degradation of hardly accessible compounds was investigated. The pre-treatment affected significantly the carbohydrates solubilisation, and was able in reducing part of the lignocellulosic matrix. Moreover, in mesophilic conditions, the high solubilized sugars content favoured the initial recovery of hydrogen (not consumed by hydrogenotrophic methanogenesis), allowing to newly assess the extent of prompt fermentability. Pre-treatment enhanced hydrogen yields of FVS and OFMSW, with gains up to +50%, while the successive methane production, occurring in the same reactor, resulted affected by the lack of the soluble part of carbohydrates, "subtracted" for H2 production. Only in thermophilic conditions, when no hydrogen in the biogas was detected, pre-treatment of OFMSW significantly increased methane yield (from 0.343 to 0.389 L CH4 g-1 VSfed). A thermal pre-treatment seems the recommended solution in order to reduce part of the recalcitrant lignocellulosic matrix of food waste, to improve energy recovery and to eliminate the extra cost needed for pasteurization.

Lewis-Brønsted acid catalysed ethanolysis of the organic fraction of municipal solid waste for efficient production of biofuels.

A combined Lewis-Brønsted acid ethanolysis of sugars was thoroughly investigated with the aim of producing ethyl levulinate (EL) in a single step. Ethanolysis carried out at 453 K for 4 h using H2SO4 (1 wt%) and AlCl3·6H2O (30 mol % with respect to sugars) produced a yield of 60 mol % of EL respect to glucose and starch. Such optimised conditions were positively applied directly on different food waste, preliminarily characterised and found to be mainly composed by simple (10-15%) and relatively complex sugars (20-60%), besides proteins (6-10%) and lipids (4-10%), even in their wet form. The catalytic system resulted robust enough to the point that the copresence of proteins, lignin, lipids and mineral salts not only did not negatively affect the overall reactivity, but resulted efficiently converted into soluble species, and specifically, into other liquid biofuels of different nature.

Biomethanization of citrus waste: Effect of waste characteristics and of storage on treatability and evaluation of limonene degradation.

This study proposes the evaluation of the suitability of mesophilic anaerobic digestion as a simple technology for the treatment of the citrus waste produced by small-medium agro-industrial enterprises involved in the transformation of Citrus fruits. Two different stocks of citrus peel waste were used (i.e., fresh and stored citrus peel waste), to evaluate the influence of waste composition (variability in the type of processed Citrus fruits) and of storage (potentially necessary to operate the anaerobic digester continuously over the whole year due to the seasonality of the production) on anaerobic degradation treatability. A thorough characterization of the two waste types has been performed, showing that the fresh one has a higher solid and organic content, and that, in spite of the similar values of oil fraction amounts, the two stocks are significantly different in the composition of essential oils (43% of limonene and 34% of linalyl acetate in the fresh citrus waste and 20% of limonene and 74% of linalyl acetate in the stored citrus waste). Contrarily to what observed in previous studies, anaerobic digestion was successful and no reactor acidification occurred. No inhibition by limonene and linalyl acetate even at the maximum applied organic load value (i.e., 2.72 gCODwaste/gVSinoculum) was observed in the treatment of the stored waste, with limonene and linalyl acetate concentrations of 104 mg/l and 385 mg/l, respectively. On the contrary, some inhibition was detected with fresh citrus peel waste when the organic load increased from 2.21 to 2.88 gCODwaste/gVSinoculum, ascribable to limonene at initial concentration higher than 150 mg/l. A good conversion into methane was observed with fresh peel waste, up to 0.33  [Formula: see text] at the highest organic load, very close to the maximum theoretical value of 0.35 [Formula: see text] , while a lower efficiency was achieved with stored peel waste, with a reduction down to 0.24  [Formula: see text] at the highest organic load.

Integrated Cancer Treatment in the Course of Metastatic Pancreatic Cancer: Complete Resolution in 2 Cases.

Pancreatic cancer (PC) has a very low average survival, but its prognosis is further reduced in the case of metastatic spread. Medical therapy in these cases is the only applicable methodology in the international guidelines. During anticancer treatments, common side effects are nausea, vomiting, arthralgia, neuropathy, and alopecia as well as a myelosuppressive effect. The toxicity of various drugs not only affects the quality of life of the patient, but often its severity requires a reduction in if not the termination of drug administration. Scientific studies have shown that a combined use of chemotherapy and certain natural substances, in the form of standardized extracts, can lead to an enhancement of the action of the chemotherapy. Here, we describe 2 cases of metastatic PC. The first case concerns the integrated treatment of a patient with cancer of the pancreas tail with metastatic involvement ab initio of peripancreatic lymph nodes and liver parenchyma, with numerous secondary lesions greater than 9.5 cm. The second case concerns the integrated treatment of a patient with cancer of the pancreatic body with metastatic involvement of the liver parenchyma, with a small secondary lesion. In both cases, an integrated cancer treatment approach, combining chemotherapy with natural remedies, extracts, and hyperthermia, induced a notable remission of primary and metastatic lesions.

Amorphous boron-doped sodium titanates hydrates: Efficient and reusable adsorbents for the removal of Pb2+ from water.

Amorphous titanium hydroxide and boron-doped (B-doped) sodium titanates hydrates were synthetized and used as adsorbents for the removal of Pb2+ from water. The use of sodium borohydride (NaBH4) and titanium(IV) isopropoxide (TTIP) as precursors permits a very easy synthesis of B-doped adsorbents at 298K. The new adsorbent materials were first chemically characterized (XRD, XPS, SEM, DRIFT and elemental analysis) and then tested in Pb2+ adsorption batch experiments, in order to define kinetics and equilibrium studies. The nature of interaction between such sorbent materials and Pb2+ was also well defined: besides a pure adsorption due to hydroxyl interaction functionalities, there is also an ionic exchange between Pb2+ and sodium ions even working at pH 4.4. Langmuir model presented the best fitting with a maximum adsorption capacity up to 385mg/g. The effect of solution pH and common ions (i.e. Na+, Ca2+ and Mg2+) onto Pb2+ sorption were also investigated. Finally, recovery was positively conducted using EDTA. Very efficient adsorption (>99.9%) was verified even using tap water spiked with traces of Pb2+ (50ppb).

Sorption properties of an amorphous hydroxo titanate towards Pb(2+), Ni(2+), and Cu(2+) ions in aqueous solution.

Titanates may be selectively used as inorganic adsorbents for heavy metal ions owing to their stability and fast adsorption kinetics. Nevertheless, the synthesis of such materials usually requires extreme reaction conditions. In this work, a new titanium-based material was rapidly synthesized under mild laboratory conditions. The obtained amorphous hydroxo titanate was tested for heavy metal sorption through kinetic and equilibrium batch tests, which indicated that the new material had high adsorption rates and adsorption capacities towards Cu(2+), Ni(2+) and Pb(2) ions. Adsorption kinetics were pseudo-second order, and equilibrium data fitted the Langmuir isotherm model. The calculated maximum adsorption capacities of Cu(2+), Ni(2+) and Pb(2+) in deionized water were around 1 mmol g(-1), and they decreased for Cu(2+) and Ni(2+) in the presence of Na(+), Ca(2+) and Mg(2+) ions, whereas the alkali metal ions did not influence Pb(2+) uptake. The efficiency of adsorption and recovery of lead ions were evaluated through column dynamic tests, by feeding the column with groundwater and tap water spiked with Pb(2+). The high performance of the hydroxo titanate over several cycles of retention and elution suggested that the product is potentially useful for the solid phase extraction of lead at trace levels in natural water samples, with potential use in metal pre-concentration for analytical applications.

Ultra-trace levels analysis of microcystins and nodularin in surface water by on-line solid-phase extraction with high-performance liquid chromatography tandem mass spectrometry.

An on-line solid phase extraction coupled with high-performance liquid chromatography in tandem with mass spectrometry (on-line SPE/HPLC/MS-MS) method for the determination of five microcystins and nodularin in surface waters at submicrogram per liter concentrations has been optimized. Maximum recoveries were achieved by carefully optimizing the extraction sample volume, loading solvent, wash solvent, and pH of the sample. The developed method was also validated according to both UNI EN ISO IEC 17025 and UNICHIM guidelines. Specifically, ten analytical runs were performed at three different concentration levels using a reference mix solution containing the six analytes. The method was applied for monitoring the concentrations of microcystins and nodularin in real surface water during a sampling campaign of 9 months in which the ELISA method was used as standard official method. The results of the two methods were compared showing good agreement when the highest concentration values of MCs were found. Graphical abstract An on-line SPE/HPLC/MS-MS method for the determination of five microcystins and nodularin in surface waters at sub µg L(-1) was optimized and compared with ELISA assay method for real samples.

Organic Carbonates: Efficient Extraction Solvents for the Synthesis of HMF in Aqueous Media with Cerium Phosphates as Catalysts.

We describe a process for the selective conversion of C6 -polyols into 5-hydroxymethylfurfural (5-HMF) in biphasic systems of organic carbonate/water (OC/W), with cerium(IV) phosphates as catalysts. Different reaction parameters such as the OC/W ratio, catalyst loading, reaction time, and temperature, were investigated for the dehydration of fructose. Under the best reaction conditions, a yield of 67.7 % with a selectivity of 93.2 % was achieved at 423 K after 6 h of reaction using [(Ce(PO4)1.5 (H2 O)(H3 O)0.5 (H2 O)0.5)] as the catalyst. A maximum yield of 70 % with the same selectivity was achieved after 12 h. At the end of the reaction, the catalyst was removed by centrifugation, the organic phase was separated from water and evaporated in vacuo (with solvent recovery), and solid 5-HMF was isolated (purity >99 %). The recovery and reuse of the catalyst and the relationship between the structure of the OC and the efficiency of the extraction are discussed. The OC/W system influences the lifetime of the catalysts positively compared to only water.

Fat, oil and grease waste from municipal wastewater: characterization, activation and sustainable conversion into biofuel.

Fat, oil and grease (FOG) recovered by the oil/water separator of a wastewater treatment plant (WWTP) were sampled, characterized, activated and converted into biofuel. Free acids (50-55%) and fatty soaps (26-32%) not only composed the main components, but they were also easily separable from the starting waste. The respective free fatty acid profiles were gas-chromatographically evaluated, interestingly verifying that free acids had a different profile (mainly oleic acid) with respect to the soapy fraction (saturated fatty acids were dominant). The inorganic composition was also determined for soaps, confirming that calcium is the most commonly present metal. The chemical activation of this fatty waste was made possible by converting the starting soaps into the respective free fatty acids by using formic acid as activator, coproducing the relevant formates. The activated fatty matter was then converted into biofuel through direct esterification under very mild conditions (345 K, atmospheric pressure) and obtaining thermodynamic conversion in less than 2 h. The process was easily scaled up, isolating at the end pure biodiesel (purity > 96%) through distillation under vacuum, providing a final product conformed to commercial purposes.

Iodinated contrast media electro-degradation: process performance and degradation pathways.

The electrochemical degradation of six of the most widely used iodinated contrast media was investigated. Batch experiments were performed under constant current conditions using two DSA® electrodes (titanium coated with a proprietary and patented mixed metal oxide solution of precious metals such as iridium, ruthenium, platinum, rhodium and tantalum). The degradation removal never fell below 85% (at a current density of 64 mA/cm(2) with a reaction time of 150 min) when perchlorate was used as the supporting electrolyte; however, when sulphate was used, the degradation performance was above 80% (at a current density of 64 mA/cm(2) with a reaction time of 150 min) for all of the compounds studied. Three main degradation pathways were identified, namely, the reductive de-iodination of the aromatic ring, the reduction of alkyl aromatic amides to simple amides and the de-acylation of N-aromatic amides to produce aromatic amines. However, as amidotrizoate is an aromatic carboxylate, this is added via the decarboxylation reaction. The investigation did not reveal toxicity except for the lower current density used, which has shown a modest toxicity, most likely for some reaction intermediates that are not further degraded. In order to obtain total removal of the contrast media, it was necessary to employ a current intensity between 118 and 182 mA/cm(2) with energy consumption higher than 370 kWh/m(3). Overall, the electrochemical degradation was revealed to be a reliable process for the treatment of iodinated contrast media that can be found in contaminated waters such as hospital wastewater or pharmaceutical waste-contaminated streams.

Efficient conversion of brown grease produced by municipal wastewater treatment plant into biofuel using aluminium chloride hexahydrate under very mild conditions.

Wastes produced by oil/water separation at the wastewater treatment plant of Bari West (Southern Italy) were taken, characterized and converted. About 12% of this material was composed of greases, mainly made of free fatty acids (50%) and soaps (34%), and was easily separable by the aqueous phase through a hot centrifugation. After chemical activation of this fatty fraction, a direct esterification was carried out under very mild conditions (320K and atmospheric pressure), converting more than 90% of the original free fatty acids into the respective methyl esters in less than 4h, by using AlCl3·6H2O. The activation energy correlated to the use of this catalyst was also calculated (Eaest=43.9kJmol(-1)). The very low cost of the biodiesel produced (0.45€L(-1)) and the associated relevant specific energy (5.02MJ kgFAMEs(-1)) make such a process a really sustainable and effective example of valorization of a waste.