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beta-Carotene and six xanthophylls (lutein, neoxanthin, violaxanthin, luteoxanthin, cryptoxanthin, and echinenone) have been identified and semiquantitatively or quantitatively determined in musts and port wines for the first time. An HPLC method was developed and compared with that of one based on thin layer cromatography with scanning densitometry. The most abundant carotenoids present in red grape varieties are beta-carotene and lutein. In wines, significant quantities of violaxanthin, luteoxanthin, and neoxanthin were found. This study was done with berries (skin and pulp), musts, and fortified wines. Some experiments were performed to follow carotenoid content from grapes to wines. Although the levels of beta-carotene and lutein found in fortified wines were lower than those found in musts, other xanthophylls, such as neoxanthin, violaxanthin, and luteoxanthin, exist in appreciable amounts in young ports.

An aerobic granular bioreactor was operated for over 4months, treating a synthetic wastewater with a high ammonium content (100mgNL-1). The inoculum was collected from a bioreactor performing simultaneous partial nitrification and aromatic compounds biodegradation. From day-56 onwards, 2-fluorophenol (2-FP) (12.4mgL-1) was added to the feeding wastewater and the system was bioaugmented with a 2-FP degrading bacteria (Rhodococcus sp. FP1). By the end of operation, complete 2-FP biodegradation and partial nitrification were simultaneously achieved. Aerobic granules remained stable over time. During the 2-FP loading, a shift in the community structure occurred, coinciding with the improvement of 2-FP degradation. DGGE analysis did not allow to infer on the bioaugmented strain presence but pyrosequencing analysis detected Rhodococcus genus by the end of operation. Together with other potential phenolic-degraders within granules, these microorganisms were probably responsible for 2-FP degradation.

A mathematical model was developed to simulate solar drying of grapes, integrating heat and mass transfer models solved by an explicit finite differences method, considering changing boundary conditions. The model simultaneously incorporated shrinkage of the product, changes in effective moisture diffusivity and dependence of thermal properties on water content and temperature. Field experiments were carried out in a mixed mode solar dryer located in the North of Portugal, with pre-blanched grapes. A good prediction of experimental solar drying curves was attained. The mathematical model can be applied for simulating solar drying of different foods, once known their specific thermo-physical properties. Simulations obtained with the developed model can be valuable for predicting accurate drying times and consequently to design, control and optimise the production of dried foods.

In this paper, we analyze the implications of assuming that the intensity of aspirations is endogenous. In accordance with empirical evidence, consumption aspirations decrease with capital accumulation while environmental ones increase. We show that such a change in the intensity of aspirations gives rise to a U-shaped relationship between capital accumulation and environmental quality. We also study the implications of our assumption concerning the optimal allocation and show that the steady-state capital stock can be larger or smaller than the one corresponding to the modified golden rule. In addition, for realistic parameter values, the decentralization of the optimal allocation requires the implementation of a maintenance investment subsidy and a lump-sum transfer from the old to the young generation.

Zn accumulation in Solanum nigrum grown in naturally contaminated soil in the presence of different types of organic amendments was assessed. Under the same conditions, the response of the plant to inoculation with two different isolates of arbuscular mycorrhizal fungi (AMF) (Glomus claroideum and Glomus intraradices) was also evaluated. S. nigrum grown in the non-amended soil always presented higher Zn accumulation in the tissues, with the addition of amendments inducing reductions of up to 80 and 40%, for manure and compost, respectively, and enhancing plant biomass yields. The establishment of S. nigrum in the Zn contaminated soil combined with the application of amendments led to a 70-80% reduction in the amount of Zn leached through the soil. The use of S. nigrum in combination with manure appeared as an effective method for reducing the effects of soil contamination, diminishing Zn transfer to other environmental compartments via percolation.

This paper presents a bibliometric research of scientific documents on biofuel production from organic wastes extracted from the Web of Science (WoS) database. Original research and conference proceeding articles published until 2022 year were considered, which resulted in 773 documents. The objective of the study was to track evolutionary nuances and emerging trends of the topic, as well as upgrade knowledge in the area and help formulate scientific policies. The work concentrated on the most productive countries, authors and journals, as well as authors’ keywords in documents relating to the biofuel conversion from biomass. The first paper on the field was published in 2004, and the publication number showed increasing trend with over 27% annual growth. The USA, followed by China demonstrated the highest publication and citation number. The thematic map analysis displayed the multidisciplinary nature of the topic, implying that the progress of several research domains is required for this technology. This is the first bibliometric review on biofuel from organic waste by microorganisms in the literature. The investigation results emphasize the need for further research in the area and also highlights the need for higher collaboration. info:eu-repo/semantics/publishedVersion

Zn tissue accumulation in Solanum nigrum grown in a non-contaminated and a naturally contaminated Zn matrix and the effect of inoculation with different arbuscular mycorrhizal fungi (AMF) on metal uptake were assessed. S. nigrum grown in the contaminated soil always presented higher Zn accumulation in the tissues, accumulating up to 1622 mg Zn kg(-1). The presence of both Glomus claroideum and Glomus intraradices enhanced the uptake and accumulation of Zn by S. nigrum (up to 83 and 49% higher Zn accumulation, respectively). The main deposits of the metal were found in the intercellular spaces and in the cell walls of the root tissues, as revealed by autometallography, with the inoculation with different AMF species causing no differences in the location of Zn accumulation. These findings indicate that S. nigrum inoculated with selected heavy metal tolerant AMF presents extracting and accumulating capacities, constituting a potentially suitable remediation method for Zn polluted soils.