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Lignocellulosic material (LCM) can be employed as feedstock for biorefineries, a concept related to industries designed to process biomass for producing chemicals, fuels and/or electrical power. According to this philosophy, LCM can be fractionated and the resulting fractions employed for specific applications. Bioethanol production from cellulosic fraction of LCM involves: hydrolysis of polysaccharides and fermentation of the monomers into bioethanol. Enzymatic hydrolysis is catalyzed by cellulolytic enzymes and fermentation is carried out by bacteria, yeasts or fungi. The main objective of this article is to review different process integration technologies for bioethanol production from LCM. This paper include: separate hydrolysis and fermentation (SHF), simultaneous saccharification and fermentation (SSF), and simultaneous saccharification and co-fermentation (SSCF) methods. Furthermore, the fermentation process and a comparative data of cellulases, hemicellulases and ethanol producing-microorganisms were presented.

Lignocellulosic materials (LCM) are produced in large quantities and without clear application and their use as raw material for bioethanol production shows economic and ecologic benefits. LCM are composed mainly of three polymers: cellulose made up of glucose units, hemicellulose made up of several sugars (as xylose or arabinose), and lignin made up of phenylpropane units, interconnected in a strong structure. Pretreatment is an important step for bioethanol production from LCM, causing the solubilisation of hemicellulosic fraction (leading to the recovery of hemicellulose-derived saccharides) in order to obtain a solid phase enriched in cellulose and more susceptible to enzymatic attack. This study provides a comparative data regarding the chemical composition of various LCM used for bioethanol production, as well as different pretreatment technologies for improving the enzymatic hydrolysis of LCM.

In recent years, iron oxides-based nanostructured composite materials are of particular interest for the preparation of multifunctional thin films and membranes to be used in sustainable magnetic field adsorption and photocatalysis processes, intelligent coatings, and packing or bio-medical applications. In this paper, superparamagnetic iron oxide (core)-silica (shell) nanoparticles suitable for thin films and membrane functionalization were obtained by co-precipitation and ultrasonic-assisted sol-gel methods. The comparative/combined effect of the magnetic core co-precipitation temperature (80 and 95 °C) and ZnO-doping of the silica shell on the photocatalytic and nano-sorption properties of the resulted composite nanoparticles were investigated by ultraviolet-visible (UV-VIS) spectroscopy monitoring the discoloration of methylene blue (MB) solution under ultraviolet (UV) irradiation and darkness, respectively. The morphology, structure, textural, and magnetic parameters of the investigated powders were evidenced by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, Brunauer–Emmett–Teller (BET) measurements, and saturation magnetization (vibrating sample magnetometry, VSM). The intraparticle diffusion model controlled the MB adsorption. The pseudo- and second-order kinetics described the MB photodegradation. When using SiO2-shell functionalized nanoparticles, the adsorption and photodegradation constant rates are three–four times higher than for using starting core iron oxide nanoparticles. The obtained magnetic nanoparticles (MNPs) were tested for films deposition.

Sweet sorghum (Sorghum bicolor (L.) Moench) represent an emerging alternative feedstock with great potential for bioethanol production. Sweet sorghum stalks can be crushed to extract the sugar-rich juice (containing mainly sucrose, glucose and fructose) which can be directly fermented into ethanol with high efficiency by Saccharomyces cerevisiae yeast. This fast-acting microorganism with high ethanoltolerance displays high ethanol yields and maintains high cell viability during the fermentation under very high gravity conditions (with high total sugar concentrations). The objective of this study is to review the current state of knowledge on the bioethanol production from stalk juice of different sweet sorghum varieties by Saccharomyces cerevisiae (industrial and isolated yeast strains), assessing also the effects of process variables, nutrient supplementation and feeding systems (batch and fed-batch fermentations) on the final ethanol concentration.

The ingestion of a large amount of certain types of beneficial bacteria can reduce the multiplication and development of pathogenic bacteria in the gut. A “probiotic” is a product that contains live microorganisms which positively influence the host intestinal microbiota by preventing the proliferation of pathogenic bacteria and promoting the growth and development of beneficial bacteria. Bacillus spp. are Gram-positive endospore-forming bacteria with beneficial effects in aquaculture industry. The dietary supplementation of Bacillus spp. in fish culture improved especially growth performance, immune response and the disease resistance of fish against pathogenic bacterial infections. The objective of the current paper is to review the recent published investigations reported in the scientific literature on the use of probiotic Bacillus spp. in aquaculture, focusing on their beneficial effects on the host. This review includes the main effects of Bacillus spp. administration in shrimp culture, carp culture, tilapia culture, and other fish culture.

This paper is a state-of-the-art review and a consolidated source of information regarding the prebiotic potential of xylooligosaccharides (XOS) derived from lignocellulosic materials (LCM) as bioactive molecules with high-added value for human health. XOS can be obtained by hydrothermal pretreatment (or autohydrolysis), a primary technological step in biological conversion of LCM into value-added products. Purification of XOS is a complex process which aims to remove unwanted compounds and to achieve the necessary degree of polymerization. Proven benefits and positive effects on the human health are mainly in the intestinal microbiota, where food-grade XOS stimulate the growth and proliferation of probiotic bacteria. The main objective of this study was to provide an in-depth overview of the recent published investigations reported in the scientific literature on the production of XOS from xylan-containing LCM by hydrothermal pretreatment, purification of hydrothermally produced XOS and, furthermore, evaluation of the bioactive properties of purified XOS.