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Sponges thrive in the deep, dark and nutrient-depleted ocean and may rely on microbial symbionts for carbon acquisition and energy generation. However, these symbiotic relationships remain largely unexplored. In this study, we analyze the microbiome of deep-sea sponges and show that ammonia-oxidizing archaea (AOA) of the family Nitrosopumilaceae make up at least 75% of the microbial communities of the sponges Aphrocallistes sp., Farrea sp. and Paratimea sp.. Given the known autotrophic metabolism of AOAs, this implies that these sponge holobionts can have the capacity for primary production in the deep-sea. We also show that specific AOA lineages are highly specific towards their hosts, hinting towards an unprecedent vertical transmission of these symbionts in deep-sea sponges. Our results show that the ecology and evolution of symbiotic relationships in deep-sea sponge is distinct from that of their shallow-water counterparts.

Calcifying organisms are considered as threatened by ocean acidification, because of their calcium carbonate skeleton. This study investigated if a calcareous sponge could synthesize its skeleton (i.e. spicules) under ocean-acidification conditions. Sponge cell aggregates that have the potential to develop into a functional sponge, called primmorphs, were submitted to a 5-day experiment, with two treatments: control (pH 8.1) and acidified conditions (pH 7.6). Primmorphs of the calcareous sponge Paraleucilla magna were able to synthesize a skeleton, even under low pH, and to develop into functional sponges. The spicules had the same shape in both conditions, although the spicules synthesized in low pH were slightly thinner than those in the control. These results suggest that P. magna may be able to survive near-future ocean-acidification conditions.

Sponges-associated microorganisms play important roles in their health and ecology; consequently, they may be crucial in the successful adaptation of exotic species to novel environments. However, few studies have focused on the microbial diversity of exotic sponges, especially those with calcium carbonate spicules (class Calcarea). Therefore, this is the first in situ characterization of the microbiota of the exotic calcareous sponges Sycettusa hastifera and Paraleucilla magna. Our results suggest that S. hastifera has a more stable microbiota than P. magna, as there were no differences in its beta diversity among sampling sites. Conversely, P. magna showed significant differences in its microbial communities, perhaps related to its adhesion to artificial substrate and/or shellfish mariculture activities. Each sponge species presented a single dominant proteobacterial OTU potentially active in the nitrogen cycle, which could help sponge detoxification, especially in polluted areas where exotic species usually establish. Our results show the importance of assessing the microbial diversity to unveil host-microorganism relationships and suggest that these associated nitrogen-cycling microorganisms could favor the success of exotic sponges in new environments.

Labor is a known risk factor for pelvic floor dysfunction (PFD); however, the impact of operative vaginal delivery (OVD), particularly spatulas, remains unclear. The aim of this study was to compare postpartum PFD symptoms in women undergoing spontaneous vaginal delivery (SVD) and those undergoing OVD. An observational prospective study (MOODS: Maternal-neonatal Outcomes in Operative Vaginal Delivery) was enrolled at Hospital de Braga from February to October 2018. All singleton term OVD (Thierry spatulas and vacuum extractor) and a convenience SVD sample were recruited, in a 2:1 ratio. To assess PFD symptoms Pelvic Floor Distress Inventory-20 (PFDI-20) was applied at 3, 6, and 12 months postpartum. The questionnaire is divided into three subscales: Urinary (UDI), Colorectal-Anal (CRADI), and Pelvic Organ Prolapse Distress Inventory (POPDI). Of the 304 women recruited, 207 were included, 34.3% with SVD and 65.7% with OVD. Thierry spatulas were used in 53.7% of women undergoing OVD. Frequency of nulliparous (p

Lignocellulosic biomass is the most abundant biological resource on the planet and has been extensively researched to produce cellulosic ethanol. However, there is a consensus that the presence of lignin hinders the biomass conversion. Lignin is often considered a villain in cellulosic ethanol production studies due to its adverse effects on cellulases and yeasts. Despite this, recent studies indicate that lignins can be transformed into useful inputs to produce cellulosic ethanol. These approaches aim to establish closed-loop biorefineries to improve economic metrics and reduce the environmental impact due to the substitution of products based on fossil sources. The present review addresses the successful cases in transforming lignin into chemicals and materials to increase cellulosic ethanol titers. A contextualization was first carried out, considering aspects of biomass characteristics and lignin valorization. The impact of lignin-based chemicals and materials in the pretreatment, detoxification, and enzymatic hydrolysis steps was discussed in detail. Economic aspects and future perspectives were also included in this review. These reports open a new point of view on lignin valorization and its integration with the cellulosic ethanol production chain.

Cactus pear biomass has the potential for bioethanol production in dry regions. However, its low solids concentration and pH variations may hinder the process of alcoholic fermentation. The objectives of this study were as follows: (1) to evaluate the effects of harvest time and season on biomass pH and dry matter concentration of cladodes of two cactus pear species commonly used as forage (Nopalea cochenillifera and Opuntia stricta); (2) to compare the hydrolysis of fresh and dried biomass (10% w v−1 solids); (3) to compare increasing periods of two temperatures (65 °C or 105 °C) to concentrate the biomass to 10% and 30% solids; and (4) to perform enzymatic hydrolysis and fermentation of biomass dried to 30% solids. Biomass pH ranged from 3.0 to 5.6, from early morning to late afternoon, with higher diurnal variation during the dry season, when their solids concentrations were higher than in the rainy season (12–16% × 7–10%). Hydrolyzed fresh and dried biomass had similar glucose, xylose, and galacturonic acid concentrations. Drying at 105 °C for 12 h was the best temperature and period to reach 30% of solids. The enzymatic hydrolysis of the biomass dried to 30% solids yielded 65.3 and 80.0 g of glucose L−1. After fermentations (33 °C; 8 h; Saccharomyces cerevisiae), ethanol was produced to 29.4 and 37.5 g L-1 from N. cochenillifera and O. stricta biomasses, respectively. Therefore, early morning during the dry season is the best moment to harvest the cladodes, whose biomass can be partially dried at 105 °C for 12 h to 30% solids load before being hydrolyzed and fermented for bioethanol production. This procedure reduces the time, energy, and inputs needed in the process.

The present study aimed to evaluate the process of anaerobic co-digestion of different proportions of food waste and fresh bovine manure. The experiments were carried out in the laboratory (using 250-mL reactors) and in a pilot-scale biodigester (8 m3). The laboratory experiment was conducted with batch feed systems testing three food waste (FW) and bovine manure (BM) ratios: 0:1, 1:2, and 3:1 (equivalent to 0, 33, and 75 % of food waste in the digester substrate, respectively). The pilot-scale biodigester had a continuous feed system and received a 1:2 FW:BM mixture ratio. The highest accumulated biogas production in the laboratory was 273 mL g-1 of volatile solids (VS) in the treatment with the 1:2 FW:BM ratio. Concentrations of volatile fatty acids (VFA) greater than 8 g L-1 inhibited methane production, except in the treatment without food waste. In the pilot-scale biodigester, concentrations of VFA were below the inhibitory threshold, and the biogas and methane yields were 271 L kgVS-1 and 220 L kgVS-1, respectively. Therefore, food waste can be successfully co-digested with fresh bovine manure in continuous feed digesters, with an initial organic load rate of at least 2.74 kgVS m-3 day-1. Future studies should aim to test progressive increases in food waste load to identify the threshold for inhibition.

Pre-treatment is one of main economic and technological challenges to render feasible the production of biofuels and chemical compounds from lignocellulosic biomass. Alkaline hydrogen peroxide (AHP) is the most used pre-treatment and recycling of its liquid fraction can help reduce production costs. The effects of four AHP concentrations (1, 3.5, 5 and 7.5% v/v) on the recycling performance of the liquid fraction of pre-treated corn stover was evaluated for five consecutive cycles. Delignification rates increased with increasing AHP concentrations in the first cycle: 15, 26, 43 and 76% with 1, 3.5, 5 and 7.5% v/v H2O2, respectively. In the following cycles, the rates decreased linearly reaching less than 40% in the last two recycles. These delignification rates and hemicellulose solubilization were corroborated by spectroscopic analyses with Fourier transformation showing reductions in lignin and hemicellulose absorbance and increases in crystallinity indices. Considering the low delignification rates in the last two cycles, the pre-treated biomasses obtained until the third cycle were submitted to enzymatic hydrolysis at 1:10 solid–liquid ratio. The delignification rates affected the efficiency of the enzymatic hydrolysis at all AHP concentrations and all recycles. The highest AHP concentration (7.5% v/v) was required to efficiently remove lignin and solubilize hemicellulose, maintaining cellulose conversion into glucose greater than 50% up to three recycles. Therefore, the technology of recycling the liquid solution of AHP pre-treatment is recommended with high initial concentrations (7.5% v/v).

In this study, sugarcane bagasse hydrolysate supplemented with different proportions of sugar-ethanol industrial waste (vinasse) was used to optimize fermentative ethanol production using two Spathaspora passalidarum yeast strains isolated from decaying wood in Amazonian biome. The bagasse samples were pretreated chemically and enzymatically before using a binary factorial experimental design. The factorial design was carried out in two stages; in the first, a 24 factorial design was done to assess the effects of pretreated sugarcane bagasse hydrolysate and vinasse, ammonium sulfate concentration, yeast biomass concentration, and two different strains of yeast, S. passalidarum; in the second stage, a 23 factorial design was done to provide a more detailed analysis of the effects of vinasse supplementation on the fermentation process—this time, by modifying the ratio of sugarcane bagasse hydrolysate and vinasse and, more significantly, the same factor—biomass concentration. The results showed that the most significant factors for increasing bioethanol production in the 24 factorial design proved to be the following: inoculum and hydrolyzed bagasse supplementation with vinasse (the optimal being 75:25), followed by yeast concentration (optimal at 14% w/v cell wet weight) and then the type of strain used (S. passalidarum UFMG-HMD-14.1). The use of only hydrolyzed bagasse without vinasse (23 factorial design) had no significant influence on the results, nor did varying the concentration of nitrogen. This increase in ethanol production, which allows the same amount of ethanol productivity through a reduction in the carbon source, suggests it can lead to an improved final use for vinasse.

Lignocellulosic biomass is a renewable and abundant resource that is suitable for the production of bio-based materials such as biofuels and chemical products. However, owing to its complex chemical composition, it requires a process that enhances the release of sugars. Pretreatment is an essential stage in increasing the efficiency of enzymatic hydrolysis of lignocellulosic biomass. The most widely used pretreatment methods operate at high temperatures (160–290 °C) and pressures (0.69 to 4.9 MPa) and generate biological growth inhibitors such as furfural and hydroxymethylfurfural (HMF). Thus, there has been a growing need to adopt new approaches for an effective pretreatment that operates at ambient temperature and pressure and reduces the generation of inhibitors. Among these methods, alkaline hydrogen peroxide (AHP) is notable because it is effective for a wide range of lignocellulosic biomass concentrations, and can provide a high degree of enzymatic hydrolysis efficiency. However, few results have been discussed in the literature. Given this, the aim of this study was to investigate the use of alkaline hydrogen peroxide (AHP) as an oxidative pretreatment agent to improve the efficiency of enzymatic hydrolysis for different types of biomass and examine the key areas of the pretreatment. Finally, there is a discussion of the challenges facing a large-scale application of this method.