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Abstract\nHIGHLIGHTSThe biomethanization of lignocellulosic wastes remains an inefficient and complex process due to lignin structures that hinder the hydrolysis step, therefore, some treatments are required. This work describes the addition of an enriched microbial consortium in the biomethanization of rice straw. The experiment was carried out in lab batch reactors following two strategies: (i) pretreatment of rice straw for 48 h using the enriched microbial consortium (dilution 1:100), and (ii) addition of this enriched microbial consortium (dilution 1:100) directly to the anaerobic reactors (bioaugmentation). The kinetic behavior was described using three models. As a result, the microbial consortium molecular characterization showed 58 different bacterial species, predominantly the Lactobacillaceae family (45.7%), and the Clostridiaceae family (19.1%), which were responsible for the positive effect obtained by bioaugmentation with methane yield increases of 16% (290 LNCH4/kgVS) respect to the control. All kinetic models applied fitted the experimental data for cumulative methane production, although the modified Hill model showed the best fit. Bioaugmentation strategies demonstrate their effectiveness in lignocellulosic biodegradation, but the novelty of this research lies in the application of an enriched microbial consortium obtained by the authors through soil isolation techniques, which are very inexpensive and affordable for developing countries.An enriched microbial consortium developed by using the effective microorganism’s technology and soils isolated was characterized.Rice straw anaerobic digestion was bioaugmented by the addition of the enriched microbial consortium.Bacterial community dynamics during rice straw anaerobic digestion were influenced by pretreatment or bioaugmentation strategies.Bioaugmentation increases the celluloses biomass availability and the methane yield (16%).Specific methanogenic activity and kinetic were influenced by adding the enriched microbial consortium.An enriched microbial consortium developed by using the effective microorganism’s technology and soils isolated was characterized.Rice straw anaerobic digestion was bioaugmented by the addition of the enriched microbial consortium.Bacterial community dynamics during rice straw anaerobic digestion were influenced by pretreatment or bioaugmentation strategies.Bioaugmentation increases the celluloses biomass availability and the methane yield (16%).Specific methanogenic activity and kinetic were influenced by adding the enriched microbial consortium. [ABSTRACT FROM AUTHOR]

Lactic acid (LA) is a versatile, optically active compound with applications across the food, cosmetics, pharmaceutical, and chemical industries, largely driven by its role in producing biodegradable polylactic acid (PLA). Due to its abundance, lignocellulosic biomass is a promising and sustainable resource for LA production, although media derived from these matrices are often rich in xylose and contain growth inhibitors. This study investigates LA production using a xylose-rich medium derived from Cynara cardunculus L. altilis DC stalks treated through steam explosion and enzymatic hydrolysis. The lactic acid bacteria strains Lacticaseibacillus casei, Paucilactobacillus vaccinostercus, and Pediococcus pentosaceus were grown on natural media, achieving yields of 0.59, 0.57, and 0.58 g LA/g total carbon consumed, respectively. Remarkably, on xylose-rich media, all supplied sugar was consumed, with LA yields comparable to those on complex media. These findings highlight the adaptability of these strains in the presence of inhibitors and support the potential of lignocellulosic biomass as a low-cost and sustainable substrate for effective PLA production. [ABSTRACT FROM AUTHOR]

Mortierella ramanniana was flask cultured with glycerol (≈ 35 g/L) being employed as substrate, under carbon and nitrogen limitation. Under carbon limitation, glycerol was rapidly consumed and total dry cell weight (X, g/L) ≈ 16 g/L containing lipid ≈ 24% w/w was synthesized. Lipids contained the important poly-unsaturated fatty acid γ-linolenic (GLA) to concentrations 9–13% w/w, with GLAmax achieved ≈ 430 mg/L. Under nitrogen limitation glycerol was slowly assimilated, lower X values (up to 12 g/L) containing higher lipid quantities (up to 45% in X) were noted and lipids contained GLA to concentrations = 6–9% w/w (GLAmax achieved was ≈ 350 mg/L). Lipid fermentation wastewater (LFW) was used as maceration water for mushrooms' solid-state fermentation. Substrates were supplemented with coffee and olive crop residues, along with soybean flour and wheat bran to achieve a low (15–20) and a high (40–60) C/N ratio. Mushrooms were studied regarding mycelial growth rates, biomass production, total phenolic compounds (TPC) consumption, enzymes (endoglucanase, laccase, manganese-dependent peroxidase/MnP) biosynthesis and exopolysaccharides (EPS) production. In high C/N, fungi exhibited the highest growth rates. Addition of LFW influenced biomass production, with the most positive effects being observed in Lentinula edodes and Pleurotus ostreatus. Substrate composition and not LFW addition impacted EPS production, while C/N had various effects on it. LFW increased TPC consumption, which was particularly evident in P. ostreatus. Low C/N induced hydrolytic and ligninolytic enzymes. LFW favored laccase production, while there was no specific pattern in endoglucanase and MnP activity. Substrates of high C/N ratio were further evaluated for carposome production, where the yield and biological efficiency-BE % were calculated. This study demonstrates the feasibility of utilizing LFW in SSF for the conversion of low-value waste into biomass, important metabolites and value-added food products. [ABSTRACT FROM AUTHOR]

Phytoremediation and constructed wetlands are widely employed processes for the decontamination of soils and waters. These sustainable, effective, and cost‐efficient technologies rely solely on the use of plants. However, the application of these processes results in the accumulation of lignocellulosic residues, like it occurs with natural wetlands, which present a significant challenge due to the potential entry into the food chain of the adsorbed pollutants or the risk of initiating uncontrolled fires due to the accumulation of dead biomass. Nevertheless, rather than being perceived as a drawback, this can be seen as a potential source of materials. Carbonaceous materials are gaining increasing significance in the field of electrochemistry, normally improving their features through some type of thermal treatment. In this study, different types of thermal treatments applied to lignocellulosic wastes are reviewed pointing out pyrolysis and hydrothermal carbonization (HTC). Additionally, four environmental and energy electrochemical applications where this type of waste has been used as precursors of electrode materials are briefly examined: energy storage (supercapacitors, Li−Na‐ion batteries), hydrogen production (H2), microbial fuel cells (MFCs) and hydrogen peroxide (H2O2) production. Recent research findings, as discussed throughout this review, suggest a promising future for the utilization of lignocellulosic waste in electrochemical applications. [ABSTRACT FROM AUTHOR]

The use of lignocellulosic residues as feedstocks for biofuels production represents an economic and ecofriendly option, since they are generated as byproducts or wastes from different industrial areas. Nevertheless, a pretreatment method aimed at eliminating the lignin content of these residues must be performed. This is required in order to increase cellulose bioavailability, which favors the production of reducing sugars through microbial or enzymatic attack. Some performed pretreatments can be classified as physical, chemical, and physicochemical methods. Although such methods are the most used pretreatments, they are expensive and generate or make use of harmful compounds. Biological methods, by the action of microorganisms or their enzymes for lignin content reduction, may be regarded as an alternative, being cheaper and more friendly to the environment than the aforementioned methods. However, until now, biological pretreatments have not shown the same yield as the previously mentioned methods in both sugar recovery and biofuel production. In that sense, the aim of this work is to review the efficiency of these methods, with the goal of clarifying their advantages and disadvantages for improvement of biofuel production.

The production of multienzymes complex that could act in different raw materials is needed to improve the bioethanol production process. We isolated bacteria from vegetable residues, identified as Bacillus velezensis (UPF-B1 and UPF-B2), which were able to simultaneously produce amylolytic and cellulolytic enzymes. The enzyme complex was produced by submerged fermentation in a media containing whole-grain triticale flour and sugarcane bagasse at pH 5.5 without supplementation with micronutrient solutions, reducing the media's costs. The combined use of raw materials (triticale and sugarcane bagasse) led to higher enzymatic activities, which is important given the need for the availability of raw materials for the industrial operation of enzyme and bioethanol production plants. The enzymes produced by UPF-B1 showed their optimum at pH 5.0–5.5 and 40 ºC, and those produced by UPF-B2 at pH 5.0–5.5 and 30–50 ºC. The multienzyme complex produced by the strain UPF-B2 allows the hydrolysis in mild temperatures, near to those of fermentation processes, avoiding the need for thermophilic yeasts in the fermentation step, being a desirable option to be used in simultaneous saccharification and fermentation processes of bioethanol production. [Display omitted] • This is the first report to identify Bacillus velezensis in fruit residues. • Enzyme complexes were produced by bacteria isolated from horti-fruit residues. • Bacterial enzymes showed industrial potential to act at pH 5.0–5.5 and 30–50 ºC. • Sugarcane bagasse and triticale were substrates as a cost-reduction strategy. [ABSTRACT FROM AUTHOR]

The increase in the world population and the rapid consumption of natural products have created problems in meeting nutritional needs. In addition, there are serious environmental problems in the use, evaluation, and disposal of bio-waste products arising from agricultural activities. The evaluation of agricultural wastes in mushroom cultivation, which is an important branch of the agricultural economy in recent years, is important in solving these problems. Cultivated mushrooms grown on some agricultural wastes have the potential to be an important food source. This study aims to investigate the possibility of using bean pods (Phaseolus vulgaris L. (BP)), chickpea pods (Cicer arietinum L. (CP)), lentil straw (Lens culinaris Medik. (LS)), and barley straw (Hordeum vulgare L. (BS)) residues in the culture of three strains of Pleurotus eryngii obtained from the Düzce University (PED), Selçuk University (PES), and Hacettepe University (PEH), Turkey. Four types of compost were prepared, consisting of a mixture of BP + CP (1:1), BP + LS (1:1), BP + BS (1:1), and BP. The shortest mycelium growing day was 14.7 days on BP + CP (1:1) in PES and the longest one was 17.7 days on BP + LS (1:1) in PEH. The shortest primordia initiation days were 24.0 and 24.3 days on BP and BP + CP (1:1) in PEH and the longest ones were 32.3, 33.7, and 34.7 days on BP + LS (1:1), BP + BS (1:1), and BP in PED. P. eryngii cultivation continued for about 72–87 days, during which an average of three products were harvested. In total yield, the minimum yield (24.3–26.7 g) per 100 g of material (70% moisture) was observed in PED and the maximum yield (28.7–33.3 g) in PEH and PES. As a result, the isolates (PES and PEH) used in the study were found to be effective on earliness primordia formation and yield. Therefore, cheaper and locally available alternative substrates, including BP, CP, LS, and BS wastes, can be tried for the production of P. eryngii and other culture mushrooms. [ABSTRACT FROM AUTHOR]

The use of lignocellulosic residues as feedstocks for biofuels production represents an economic and ecofriendly option, since they are generated as byproducts or wastes from different industrial areas. Nevertheless, a pretreatment method aimed at eliminating the lignin content of these residues must be performed. This is required in order to increase cellulose bioavailability, which favors the production of reducing sugars through microbial or enzymatic attack. Some performed pretreatments can be classified as physical, chemical, and physicochemical methods. Although such methods are the most used pretreatments, they are expensive and generate or make use of harmful compounds. Biological methods, by the action of microorganisms or their enzymes for lignin content reduction, may be regarded as an alternative, being cheaper and more friendly to the environment than the aforementioned methods. However, until now, biological pretreatments have not shown the same yield as the previously mentioned methods in both sugar recovery and biofuel production. In that sense, the aim of this work is to review the efficiency of these methods, with the goal of clarifying their advantages and disadvantages for improvement of biofuel production. [ABSTRACT FROM AUTHOR]

Abstract Phytoremediation and constructed wetlands are widely employed processes for the decontamination of soils and waters. These sustainable, effective, and cost‐efficient technologies rely solely on the use of plants. However, the application of these processes results in the accumulation of lignocellulosic residues, like it occurs with natural wetlands, which present a significant challenge due to the potential entry into the food chain of the adsorbed pollutants or the risk of initiating uncontrolled fires due to the accumulation of dead biomass. Nevertheless, rather than being perceived as a drawback, this can be seen as a potential source of materials. Carbonaceous materials are gaining increasing significance in the field of electrochemistry, normally improving their features through some type of thermal treatment. In this study, different types of thermal treatments applied to lignocellulosic wastes are reviewed pointing out pyrolysis and hydrothermal carbonization (HTC). Additionally, four environmental and energy electrochemical applications where this type of waste has been used as precursors of electrode materials are briefly examined: energy storage (supercapacitors, Li−Na‐ion batteries), hydrogen production (H2), microbial fuel cells (MFCs) and hydrogen peroxide (H2O2) production. Recent research findings, as discussed throughout this review, suggest a promising future for the utilization of lignocellulosic waste in electrochemical applications.

Coffee is one of the most important agricultural products in Colombia. To date, small-scale Colombian coffee growers have developed this activity with a simple infrastructure and random use of water that generates harmful by-products to the water resource mainly in the stage of separation of the mucilage. The coffee mucilage wastewater (CMW) is composed of high organic loads and its impact on water sources is due to its high load of nutrients such as nitrogen (N), phosphorus (P), and chemical oxygen demand (COD) values of over 25,000 mg/L. However, there is no consensus on what treatment can be used, especially whether it is accessible to coffee producers. Thus , the aim of this study consisted of assessing the performance of the combination of a carbon filter (CF) as pretreatment and vertical flow wetland (VFW) as a Natural-based Solution (NbS). The results show a reduction of more than 85% of COD, 96% of total solids, and UV254 close to 94%. It was remarkable that both treatments are appropriate for waters with a high concentration of solids. Finally, it can be concluded that CF + VFW is a feasible technology to treat the coffee wastewater from small communities of coffee producers. HIGHLIGHTS It is feasible to treat waters from the peeled cherry coffee process through NbSs as the vertical flow wetlands.; The proposed CF + VFW system is appropriate for dispersed rural communities in Colombia.; UV254 can be a complementary measure to evaluate performance in complex waters such as CMW.; This work contributes to improving the coffee production chain because the impact on the receiving sources of small producers decreases.;

The cultivation of oyster mushrooms is becoming increasingly popular around the world due to their ability to transfer lignocellulosic waste into balanced food. Therefore, in this current study, we focus on the domestication of Pleurotus spp., Pleurotus eryngii var. ferulae, and Pleurotus eryngii var. elaeoselini on different media, cereal grains, and various lignocellulosic substrates. Results reveal that Malt Extract Agar is suitable as a medium for the domestication of the two strains in comparison with Potato Dextrose Agar. This result is proven by its high growth rate (64.33%) with Pleurotus eryngii var. elaeoselini and (52.42%) with Pleurotus eryngii var. ferulae. Lolium perenne grains have the shortest duration to generate a spawn for Pleurotus eryngii var. ferulae. Ten substrate formulas were evaluated in this study as follows T1 (100% wheat straw), T2 (100% cardboard), T3 (100% spent coffee grounds), T4 (100% olive pomace), T5 (50% wheat straw + 50% Cardboard); T6 (75% wheat straw + 25% Cardboard 5% wheat bran); T7 (50% wheat straw + 50% Coffee ground), T8 (75% wheat straw + 25% Coffee grounds + 5% wheat bran), T9 (50% Wheat straw + 50% Olive pomace), T10 (75% wheat straw + 25% Olive pomace + 5% wheat bran). For Pleurotus eryngii var. elaeoselini cultivation, T5 (50% wheat straw + 50% Cardboard) has the significantly highest number of primordia with 30 primordia after 27 days of incubation. Regarding Pleurotus eryngii var. ferulae, the primordia number was significantly high with T8 (75% wheat straw + 25% spent coffee grounds + 5% wheat bran), with about 16 primordia after 44 days. [ABSTRACT FROM AUTHOR]

Bacteria and yeast are being intensively used to produce biofuels and high-added-value products by using plant biomass derivatives as substrates. The number of microorganisms available for industrial processes is increasing thanks to biotechnological improvements to enhance their productivity and yield through microbial metabolic engineering and laboratory evolution. This is allowing the traditional industrial processes for biofuel production, which included multiple steps, to be improved through the consolidation of single-step processes, reducing the time of the global process, and increasing the yield and operational conditions in terms of the desired products. Engineered microorganisms are now capable of using feedstocks that they were unable to process before their modification, opening broader possibilities for establishing new markets in places where biomass is available. This review discusses metabolic engineering approaches that have been used to improve the microbial processing of biomass to convert the plant feedstock into fuels. Metabolically engineered microorganisms (MEMs) such as bacteria, yeasts, and microalgae are described, highlighting their performance and the biotechnological tools that were used to modify them. Finally, some examples of patents related to the MEMs are mentioned in order to contextualize their current industrial use. [ABSTRACT FROM AUTHOR]

There is a global trend to replace the production of conventional recyclable plastics with biobased ones, allowing a sustainable alternative adapted to the current concept of a circular bioeconomy. Forest-industrial and agricultural biomass wastes (lignocellulosic biomass waste, LCBW) produce severe problems in some developing countries because they are improperly disposed of or burned in the open air. Such wastes are attractive as a raw material to produce bioplastics due to their low cost. Furthermore, low-pollution processes can complete an economical and environmentally friendly approach. This review focuses on bio-polyethylene furanoate (PEF) production from LCBW as an alternative for polyethylene terephthalate (PET), one of the most widely used fossil-based plastic. The standpoint is based on the replacement of fossil-based monomers for the manufacture of PET, terephthalic acid (TPA), and ethylene glycol by two bio-based monomers, namely 2,5-furandicarboxylic acid (FDCA) and bio-ethylene glycol (Bio-MEG). This study describes the processes to obtain each bio-monomer, as well as the resulting polymers’ performance aspects, biodegradability, environmental and economic considerations, and recycling.

Background: Ganoderma spp. are a great source of bioactive molecules. The production and recovery of bioactive molecules vary according to strain, growth substrate, and extraction solution. Variations in protease and their inhibitors in basidiomata from a commercial strain ( G. lingzhi ) and an Amazonian isolate ( Ganoderma sp.) cultivated in Amazonian lignocellulosic wastes and extracted with different solutions are plausible and were investigated in our study., Methods: Basidiomata from cultivation in substrates based on açaí seed, guaruba-cedro sawdust and three lots of marupá sawdust were submitted to extraction in water, Tris-HCl, and sodium phosphate. Protein content, proteases, and protease inhibitors were estimated through different assays. The samples were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR)., Results: Tris-HCl provided higher protein extraction from Ganoderma sp. and higher caseinolytic, gelatinolytic, and fibrinolytic activity for G. lingzhi cultivated in açaí. Water extracts of Ganoderma sp., in general, exhibited higher trypsin and papain inhibitor activities compared to G. lingzhi. Extracts in Tris-HCl and sodium phosphate showed more intense protein bands in SDSPAGE, highlighting bands of molecular weights around 100, 50, and 30 kDa. FTIR spectra showed patterns for proteins in all extracts, with variation in transmittance according to substrate and extractor., Conclusion: Water extract from Amazonian Ganoderma sp. cultivated in marupá wastes are promising as a source of protease inhibitors, while the Tris-HCL extract of G. lingzhi from açaí cultivation stands out as a source of proteases with fibrinolytic, caseinolytic, and gelatinolytic activities., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Cellulose is a natural, unbranched, and fibrous homopolymer that is a major component in several agroindustrial residues. The aim of this study was to extract cellulose from oat hulls and then to modify it using a green route to obtain esterified cellulose through reaction with organic acids employing the reactive extrusion process, which is a process that presents some advantages, including low effluent generation, short reaction times, and it is scalable for large scale use. Citric (CA) and succinic (SA) acids were employed as esterifying agents in different concentrations (0, 5, 12.5, and 20%). Modified cellulose samples were characterized by their degree of substitution (DS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (DRX), scanning electron microscopy (SEM), wettability, oil and water absorption capacities, and thermal stability. DS of modified samples ranged from 2.28 to 3.00, and FTIR results showed that the esterification occurred in all samples for both acids by observation of important bands at 1720 and 1737 cm−1 for samples modified with CA and SA, respectively. All modified samples presented increased hydrophobicity. The modification did not have an influence on the morphological structure or crystallinity pattern of all samples. This study proved to be possible to modify cellulose using a simple and ecofriendly process based on reactive extrusion with organic acids.

The energy use of fruit tree pruning represents a current alternative to achieving an energy transition toward clean biomass resources, which can substitute for fossil fuels and mitigate polluting emissions. In Mexico, avocado is one of the most important fruit crops, with approximately 260,000 ha planted. The pruning of avocado trees generates large amounts of biomass that are not fully exploited, lacking studies that analyze in depth the energy potential of pruning. This study aims to determine the potential energy use of avocado pruning as densified solid biofuels. The physical, chemical and energetic properties of two pruning fractions defined as class B (branches) and class BAL (branches and leaves) were determined. From class B, pellets were made, and their physical and mechanical properties were determined. Subsequently, the evaluated parameters of the pellets obtained were compared to European quality regulations to determine their quality and identify their potential uses. The characterization of avocado pruning indicates that class B generally has better physicochemical characteristics than class BAL to be used as solid biofuel. It was found that class B has a high calorific value (19.61 MJ/kg) and low ash content (1.2%), while class BAL contains a high amount of ash (7.2%) and high levels of N (1.98%) and S (1.88%). The manufactured pellets met most of the quality requirements for immediate use in the residential, commercial and industrial sectors at the regional level. [ABSTRACT FROM AUTHOR]

Various carbon-rich solid catalysts are evaluated for the synthesis of biodiesel from waste frying oil. The study results showed that the use of activated carbon made of corn stalk could increase the biodiesel yield by 7%. The heterogeneous carbon-based catalysts made of lignocellulosic residues could successfully improve the quality of biodiesel properties. The results obtained revealed that the biodiesel properties, including relative density (852–900 kg·m−3) and kinematic viscosity (2.4–3.9 mm2·s−1), are in compliance with the standard limits of ASTM and the European Biodiesel Standard, suggesting that the biodiesel produced would be decent as a diesel fuel that potentially can minimize the serious damage of engine parts, and prolong the engine life.

Bacteria and yeast are being intensively used to produce biofuels and high-added-value products by using plant biomass derivatives as substrates. The number of microorganisms available for industrial processes is increasing thanks to biotechnological improvements to enhance their productivity and yield through microbial metabolic engineering and laboratory evolution. This is allowing the traditional industrial processes for biofuel production, which included multiple steps, to be improved through the consolidation of single-step processes, reducing the time of the global process, and increasing the yield and operational conditions in terms of the desired products. Engineered microorganisms are now capable of using feedstocks that they were unable to process before their modification, opening broader possibilities for establishing new markets in places where biomass is available. This review discusses metabolic engineering approaches that have been used to improve the microbial processing of biomass to convert the plant feedstock into fuels. Metabolically engineered microorganisms (MEMs) such as bacteria, yeasts, and microalgae are described, highlighting their performance and the biotechnological tools that were used to modify them. Finally, some examples of patents related to the MEMs are mentioned in order to contextualize their current industrial use.

The extensive utilization of conventional plastics has resulted in a concerning surge in waste. A potential solution lies in biodegradable polymers mostly derived from renewable sources. Cupriavidus necator DSM 545 is a microorganism capable, under stress conditions, of intracellularly accumulating Poly(3-hydroxybutyrate) (PHB), a bio-polyester. This study aimed to identify optimal conditions to maximize the intracellular accumulation of PHB and its global production using natural media obtained by processing lignocellulosic residues of cardoon, a low-cost feedstock. An intracellular PHB accumulation was observed in all of the tested media, indicating a metabolic stress induced by the lack of macronutrients. Increasing C/N ratios led to a significant decrease in cellular biomass and PHB production. Furthermore C. necator DSM 545 was incapable of consuming more than 25 g/L of supplied monosaccharides. Surprisingly, in the samples supplied with 60 % of the pentose-rich liquid fraction, complete consumption of xylose was observed. This result was also confirmed by subsequent tests using Medium 1 growth media containing xylose as the sole carbon source. Using a diluted medium with a C/N ratio of 5, a PHB production of 5.84 g/L and intracellular PHB accumulation of 77 % w/w were respectively achieved. Finally, comparative shelf-life tests conducted against conventional pre-packaging materials in PP suggested that PHB films performed similarly in preserve ready-to-eat products. [Display omitted] • C. necator DSM 545 productively grew on lignocellulosic-derived culture media. • C. necator DSM545 accumulated up to 77 % w/w of intracellular PHB • A PHB production of 5.84 g/L was achieved with a C/N ratio 5. • PHB film demonstrated food packing performance comparable to conventional PP. • C. necator consumed all the xylose supplied in the growth media. [ABSTRACT FROM AUTHOR]

The northern zone of Costa Rica has extensive forestry and agro-industrial development, which generates a large number of lignocellulosic residues that do not have an economic value but could represent a vast energy potential. Therefore, the objective of this study was to determine the optimal size and location of an electricity generation plant from the forest and agro-industrial biomass. The researchers worked with two forest species residues (Gmelina arborea and Tectona grandis) and two agro-industrial residues (Ananas comosus and Saccharum officinarum), representing the most extensive cultivations in the region. The material was characterized, then GIS layers of the species cultivation areas were analyzed and related to the roads and protected areas to define the twelve potential points where the power plant should be installed. Later, the optimal supply radius of the plant and the optimal site conditions were determined. The study determined that the tree species have an average caloric power of 19,059.50 kJ/kg, significantly higher than agro-industrial (16,684.9 kJ/kg). It was determined that 1,056,527.67 tons of dry biomass are generated per year; 6.5% arboreal and 79.97% from A. comosus. The minimum electricity generation capacity is 15 MW with an annual consumption of 102,300 tons, which are available between 15 and 100 km away from the sites. The southeast area was the best positioned because of the biomass source and optimal environmental conditions for establishing the power plant. [ABSTRACT FROM AUTHOR]

BACKGROUND Coffee husks (CH) are an abundant lignocellulosic residue that can be converted into biofuels and bioproducts through sustainable and economical processes in a biorefinery approach. For that, steam explosion (SE) pretreatment stands out as a technique to overcome its recalcitrant nature and enable byproduct valorization. In this study, solid and liquid fractions were separated after pretreatment for saccharification and biogas production, respectively. The research relevance relies on the contribution to environment decarbonization and monetization of decarbonization credits (CBIO) generated from the production of renewable fuel from waste biomass under different operational conditions (with and without pretreatment). RESULTS: Liquid hydrolysate generated by SE condition at 210 °C and 15 min led to the highest biomethane production (292 NmL CH4 g CODfed−1). Similarly, high‐severity pretreatment also favored the enzymatic hydrolysis yield of the solid fraction (49%). In terms of environment decarbonization, SE promoted not only a lower carbon intensity when compared to the process without any pretreatment (3.8 vs. 6.4 g CO2eq MJ−1), but also increased the monetization of decarbonization credits by 175%, which represented a potential revenue of US $1 481 330. CONCLUSION: High temperatures of SE pretreatment of CH at 210 °C were able to promote biogas production and fermentable sugars. In addition, the process reduced carbon emissions and increased the revenue from CBIO commercialization. Therefore, SE proved to be a sustainable and economic alternative for consideration in new green businesses from lignocellulosic residues such as CH. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Increasing awareness due to climate change have been stimulating the development of renewable energies. Slow pyrolysis is considered a good method to produce high calorific value char, especially using lignin-rich sources. Along with calorific value, the ignition temperature is another important factor to classify biofuels as it is the minimum required temperature for self-sustaining combustion. Pyrolysis is responsible not only for improving the calorific value of biomass, but also for increasing its ignition, thus demanding more energy for char combustion. Therefore, the production of a char with energetic potential and improved combustibility is important. Here, chars produced at 300–700 °C and blended with biomass were evaluated according to their higher heating value (HHV) and ignition temperature by thermal analysis. The ash content of chars produced at higher temperatures limited their energetic potential. Depending on the ratio, blending char with biomass improved its combustibility without compromising its HHV. [ABSTRACT FROM AUTHOR]

The continuous production of biohydrogen by dark fermentation was evaluated in a bench reactor with thermally pretreated anaerobic sludge and synthetic solution of xylose supplemented with nutrients. The reactor operated at 35 °C in semi-continuous mode, which consisted of 16 h feeding cycles (for a hydraulic retention time of 48 h), mixing until completing 19 h of fermentation, and stopping the mixture for 5 h for sedimentation of sludge, followed by the withdrawal of supernatant. The reactor was operated with standard xylose as substrate for 70 days under different chemical oxygen demand (COD) loads and mixing modes during fermentation (intermittent or continuous). A yield of 1.4 mmol H2/mmol xylose was obtained under an organic loading rate of 2.5 g COD/L.d. The consumption of xylose (76.5%) and the H2 yield, which was approximately 41% of the maximum theoretical yield (3.33 mmol H2/mmol xylose with acetic acid as a byproduct), indicates that further studies are necessary to optimize the biohydrogen production in semi-continuous reactors. However, the following parameters led to greater stability of H2 production: adaptation of microorganisms to xylose through prolonged operation in a semi-continuous regime as well as the constant mixing of the reactor contents to reduce gradients of pH, organic acids, and local inhibition of microorganisms. Additionally, an increase in influent alkalinity maintained the pH at levels suitable for H2 producers. [ABSTRACT FROM AUTHOR]

Cellulose is a natural, unbranched, and fibrous homopolymer that is a major component in several agroindustrial residues. The aim of this study was to extract cellulose from oat hulls and then to modify it using a green route to obtain esterified cellulose through reaction with organic acids employing the reactive extrusion process, which is a process that presents some advantages, including low effluent generation, short reaction times, and it is scalable for large scale use. Citric (CA) and succinic (SA) acids were employed as esterifying agents in different concentrations (0, 5, 12.5, and 20%). Modified cellulose samples were characterized by their degree of substitution (DS), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (DRX), scanning electron microscopy (SEM), wettability, oil and water absorption capacities, and thermal stability. DS of modified samples ranged from 2.28 to 3.00, and FTIR results showed that the esterification occurred in all samples for both acids by observation of important bands at 1720 and 1737 cm−1 for samples modified with CA and SA, respectively. All modified samples presented increased hydrophobicity. The modification did not have an influence on the morphological structure or crystallinity pattern of all samples. This study proved to be possible to modify cellulose using a simple and ecofriendly process based on reactive extrusion with organic acids. [ABSTRACT FROM AUTHOR]

The effect of adding different lignins on the physical and mechanical properties of particleboards made with stems of hydrangea and pine using the urea–formaldehyde (UF) resin was evaluated. Four types of lignin were characterized by Fourier-transform infrared spectroscopy and Klason lignin: Cane Bagasse lignin, Pine China lignin, Kraft Brazil lignin, and ammonium lignosulfonate (LSA). Particleboards were prepared with four types of lignin in a 1:1 (w/w) UF/lignin ratio and compared with those prepared with the UF resin without lignin (control sample). Water absorption, thickness swelling, rupture modulus, and modulus of elasticity were measured. The type of lignin used does not have a statistically significant difference in the physical and mechanical properties and also a decrease in the physical properties of the particleboards compared with the control sample. The use of LSA in the 3:1 (w/w) UF/lignin ratio allows to elaborate particleboards with mechanical properties like those found in the control sample. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two Trichoderma strains were isolated from the rhizospheric soil of medicinal plants. • Fermentation factors of lignocellulosic residues by Trichoderma strains was assessed. • Substrate components was a crucial factor affecting fermentation results. • T. afroharzianum showed pronounced cellulose degradation efficiency for corn straw. • Two Trichoderma strains would be useful for application in waste materials treatment. To achieve an economically viable substitutive strategy for lignocellulosic residues use, cellulose degradation by efficient Trichoderma strains become a key alternative. This study aimed to explore the effects of various cultural conditions on the degradation of different lignocellulosic substrates (corn straw and licorice residues) by Trichoderma longibrachiatum and Trichoderma afroharzianum in solid state fermentation. The strains were isolated from the rhizospheric soils of medicinal plants. In addition, the best fermentation combination was selected to evaluate the degradation results. This study confirmed that fermentation conditions and different components of corn straw and licorice residues were both crucial factors affecting the cellulase activity and spore production of two Trichoderma strains. A combination of T. afroharzianum degrading corn straw was selected for Response Surface Methodology optimization. The best fermentation conditions were fermentation time of 5.72 days, initial material liquid ratio of 1:4.58, initial pH of 6.32 and fermentation temperature of 28.8 ℃, with a filter paper cellulase activity of 0.91 U/mL. After continuous fermentation, the spore production reached 6.18 × 109 spores/g, the crude fiber degradation rate reached 23.5 % with the reducing sugar content maintained at 11 mg/g. These results highlight the great potential of T. afroharzianum degrading corn straw for organic amendment. [ABSTRACT FROM AUTHOR]

The xylonate was bioproduced directly from lignocellulosic residues, and the application properties of crude xylonate powder were investigated with a promising potential as a bio-based concrete water reducer. The overall integrated process was evaluated on the view of mass balance and techno-economic analysis using Aspen Plus modeling. 56 g/L of calcium xylonate (XA-Ca) can be obtained within 8 h from acidic corncob hydrolysate (ACH) at a 100 % yield with the whole-cell catalysis of Gluconobacter oxydans. At the addition of 0.2 wt% in the dry concrete content, XA-Ca powder and sodium xylonate powder prepared from pure xylose and ACH could reduce water used in concrete by 15 %, 14 %, 13 %, and 13 %, respectively. XA-Ca from ACH led to a 33% increase in concrete compressive strength and a 24% increase in concrete flexural strength at day 7 compared to the blank group. The techno-economic analysis showed the minimum XA-Ca powder price to be $ 0.806/kg which can be economically feasible. This study provides a practical and economical process prototype for the industrial concrete water reducer application of novel bio-based xylonate produced from lignocellulosic residues. [Display omitted] • Xylonate powder is produced directly from lignocellulosic residues. • Xylonate is tested for concrete water-reducer. • 0.2 wt% of XA-Ca reduces 15% water used for concrete. • Aspen plus models xylonate bioproduction and application. [ABSTRACT FROM AUTHOR]

The use of different lignocellulosic residues for the production of cellulosic ethanol is an alternative for the expanding demand of this fuel without increasing the planting area of traditional carbohydrate crops. One of the proposed alternatives is the use of pineapple leaf fibers (PALF) residues, which is a material rich in cellulose that can be used as raw material for second-generation (2G) ethanol production. In this study, the PALF was pretreated using an alkaline medium combined with a steam explosion and the 2G ethanol produSction was analyzed by two-way processes to enzymatic hydrolysis using separated hydrolysis and fermentation (SHF) or simultaneous saccharification and fermentation (SSF). Using SHF, the alcoholic fermentation process with addition of molasses provided good fermentability and can handle larger loads of carbohydrate in shorter fermentation time. The SSF was a better method for 2G ethanol production from PALF yielding 96.12%. Therefore, PALF is presented as good raw material for production of 2G ethanol, with all the environmental and social advantages of such approach.

This six-month study aimed to evaluate the removal of total nitrogen (TN) in two duplicated partially saturated (PS) vertical flow (VF) wetlands added with corncob in two different heights of the free-drainage zone (FDZ) after two years in operation. Both PS VF wetlands efficiently removed organic matter measured as biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) as well as total suspended solids (TSS) achieving average mass removal efficiencies of 95.3%, 83.2% and 92.9%, respectively, in system I (SI) and 96.3%, 84.0% and 94.9%, respectively, in system II (SII); with no significant differences (p > 0.05) between the systems. Measurements of oxidation-reduction potential (ORP), dissolved oxygen (DO), pH and electrical conductivity (EC) showed suitable conditions in the saturated zone (SZ) of the systems for denitrification process. TN removal was similar in both systems (p > 0.05) (51.5% and 52.9% in SI and SII), and decreased in 15% with respect to the first year. This decrease was due to the lower denitrification capacity of the FDZ as a result of the reduction in the supply of biodegradable carbon by corncob. Denitrification occurred in the SZ, but not at a sufficient level to increase TN removal. Novelty First, the use of lignocellulosic residues in partially saturated vertical wetlands to promote total nitrogen removal is very recent. Furthermore, to the best of our knowledge, this is the first study evaluating TN removal after two years of operation in this type of wetland. Therefore, this study allows us to better understand the function of these systems, in a relatively long term. Thanks to this study: it is possible to confirm that the main process of TN elimination is through the simultaneous nitrification-denitrification process in the free drainage zone (denitrification in the saturated zone is irrelevant) and that TN elimination decreases due to the reduction in carbon supply from the corn, in this area. [ABSTRACT FROM AUTHOR]

The laccase producing abilities of four Basidiomycete fungi species were compared using solid-state fermentation using four different lignocellulosic residues. The biosynthetic potential of the Basidiomycetes was highly dependent on the type of fungi. In general, the laccase secreting ability of Cerrena unicolor Han 849 was greater than Lenzites betulinus Han 851, Stropharia rugosoannulata Han 1321, and Auricularia heimuer Han 1333. The maximum laccase production of C. unicolor Han 849 was approximately 11.25, 122.26, and 15.27 times higher than L. betulinus Han 851, S. rugosoannulata Han 1321 and A. heimuer Han 1333, respectively. Different species of fungi had a preference in lignocellulosic residues. The presence of Firmiana platanifolia was conducive to secreting laccase via C. unicolor Han 849 during solid-state fermentation. A continuous and stable laccase production via C. unicolor Han 849 was an obvious advantage of solid-state fermentation with any of the four lignocellulosic residues used. The maximum laccase production of C. unicolor Han 849 using Firmiana platanifolia was approximately 2.12, 1.68, and 6.13 times higher than Populus beijingensis, Sorghum bicolor, and Oryza sativa, respectively. These findings will be helpful for developing new productivity strains in industrial applications and selecting suitable lignocellulosic residues for laccase production. [ABSTRACT FROM AUTHOR]

BACKGROUND: Orange bagasse (OB) is an agroindustrial residue of great economic importance that has been little explored for the extraction of cellulose. The present study aimed to investigate different combinations of chemical (sodium hydroxide, peracetic acid and alkaline peroxide) and physical (autoclaving and ultrasonication) treatments performed in one‐step processes for cellulose extraction from OB and to characterize the materials obtained according to their composition, morphology, crystallinity and thermal stability. RESULTS: The processing yields ranged from 140 to 820 g kg−1, with a recovery of 720–1000 g kg−1 of the original cellulose. Treatments promoted morphological changes in the fiber structure, resulting in materials with higher porosity, indicating partial removal of the noncellulosic fractions. The use of combined chemical treatments (NaOH and peracetic acid) with autoclaving was more efficient for obtaining samples with the highest cellulose contents. CONCLUSION: Therefore, ACSH (processed by autoclaving with NaOH) was the most effective one‐step treatment, resulting in 71.1% cellulose, 0% hemicellulose and 19.0% lignin, with a crystallinity index of 42%. The one‐step treatments were able to obtain materials with higher cellulose contents and yields, reducing reaction times and the quantity of chemical reagents employed in the overall processes compared to multistep conventional processes. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The present study aimed to optimize the enzymatic hydrolysis process to degrade cellulose from corn stubble (Zea mays), using enzymes from Aspergillus niger. During the first phase of the experimentation, the content of dry matter, organic matter, ash, crude protein, ethereal extract, lignin and cellulose content of the stubble was determined, using the reference methods of the U. Florida 1970 for its quantification. Subsequently the pre-drying and grinding of the same was carried out, prior to the alkali and acid-alkali pre-treatment processes applied, being dried at 4 different temperatures (45, 50, 55 and 60 ®C). The pretreated residues were subjected to hydrolysis with Aspergillus Niger cellulases (39,125 EU) at different pHs (4.0, 4.8 and 5.6), for 24, 48 and 72 h. at 45, 50, 55 and 60 ®C temperature; quantifying the concentrations of reducing sugars released during digestion. Finally, it was determined that the hydrolysis of the stubble without pretreatment and drying at 60 ®C, at a pH of 4.8 for 72 h., had high concentrations of reducing sugars, becoming an alternative for its use as food or biofuel, after the application of biotechnological processes. [ABSTRACT FROM AUTHOR]

Several studies related to effluents treatment containing heavy metals have been developed, especially those that enable the application of lignocellulosic residues and natural polymers as well as chitosan to obtain adsorbents. In this study, carboxymethylcellulose (CMC) was obtained from corn stover to react with chitosan (CH) and ferulic acid (F) to synthesize a bioadsorbent (CMCCHF). This biomaterial was characterized by Fourier transform infrared spectra, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and nuclear magnetic resonance. The ideal application condition of CMCCHF in the hexavalent chromium adsorption process was established resulting in a pH of 3.0, 60 min of contact time, and 20 °C of temperature by a physisorption process, according to the pseudo-second order kinetic model and Langmuir isotherm model, respectively. The results showed a maximum adsorption capacity of 80.31 ± 0.67 mg g−1 for the bioadsorbent CMCCHF and 55.04 ± 0.84 mg g−1 for chitosan, which suggests an increase in the adsorption capacity of approximately 46%. A decrease in the solubilization of the adsorbent in acid medium was also observed when compared to chitosan, which favors its application in low pH adsorption processes. [ABSTRACT FROM AUTHOR]

Agro‐industrial wastes are used as carbon precursors in the production of activated carbon because they are rich in lignocellulosic materials. This study aimed to investigate the relationship between the main characteristics of precursor materials and activated carbons by multivariate analysis. After characterization of the precursor materials and their respective carbons, the principal component analysis and canonical correlation analysis were performed. Materials with cellulose/lignin ratio > 3.0 led to the production of carbons with a higher pore diameter, while materials with a cellulose/lignin ratio ≤ 1.0 led to a low pore volume. Using the mathematical models obtained, it is possible to predict the carbon characteristics using only the composition data of the lignocellulosic materials. [ABSTRACT FROM AUTHOR]

Densification and torrefaction are potential technologies to valorize lignocellulosic residues into cleaner and sustainable alternative energy carriers for domestic, institutional, commercial and industrial thermal energy applications. Therefore, this review paper has focused on sources of lignocellulosic biomass for energy production. Furthermore, the processes involved in production of raw and torrefied briquettes/pellets have been discussed. Additionally, the physicomechanical, emissions and combustion properties of raw and torrefied briquettes produced from lignocellulosic residues have been presented. Also, the economics of briquetting lignocellulosic biomass materials have also been reviewed. The quality of densified solid biomass fuels from lignocellulosic residues was found to dependent on the feedstock and pretreatment conditions. Additionally, torrefaction and densification have been reported to upgrade the energy properties of loose biomass materials, as potential alternative fuel to firewood and charcoal. Finally, the economic profitability of densification projects has been found to be dependent on the availability of feedstocks, technology used and market potential of the product. [ABSTRACT FROM AUTHOR]

Pretreatment and codigestion are proven to be effective strategies for the enhancement of the anaerobic digestion of lignocellulosic residues. The purpose of this study is to evaluate the effects of pretreatment and codigestion on methane production and the hydrolysis rate in the anaerobic digestion of agricultural wastes (AWs). Thermal and different thermochemical pretreatments were applied on AWs. Sewage sludge (SS) was selected as a cosubstrate. Biochemical methane potential tests were performed by mixing SS with raw and pretreated AWs at different mixing ratios. Hydrolysis rates were estimated by the best fit obtained with the first-order kinetic model. As a result of the experimental and kinetic studies, the best strategy was determined to be thermochemical pretreatment with sodium hydroxide (NaOH). This strategy resulted in a maximum enhancement in the anaerobic digestion of AWs, a 56% increase in methane production, an 81.90% increase in the hydrolysis rate and a 79.63% decrease in the technical digestion time compared to raw AWs. On the other hand, anaerobic codigestion (AcoD) with SS was determined to be ineffective when it came to the enhancement of methane production and the hydrolysis rate. The most suitable mixing ratio was determined to be 80:20 (Aws/SS) for the AcoD of the studied AWs with SS in order to obtain the highest possible methane production without any antagonistic effect.

Thermo-alkali-stable and cellulase-free xylanases finds vital applications in pulp bleaching and biomass conversion processes. The objective of the study was to optimize xylanase production by a novel isolate, Geobacillus thermodenitrificans X1. Different physico-chemical parameters were tested for xylanase production by one-factor-at-a-time (OFAT) approach, followed by statistical optimization using response surface methodology (RSM). Various lignocellulosic residues such as wheat straw, rice straw, corn cob and wheat bran were compared with the commercial xylan for xylanase production. The maximum xylanase activity production of 18.5 U/mL was achieved after OFAT optimization at 50 °C and pH 7–8, 200 rpm, after 96 h of incubation time. Subsequently, RSM optimization resulted in 1.3-fold increase in xylanase activity, i.e. 24 ± 2 U/mL. The present study reports the highest xylanase production on lignocellulosic residue (wheat straw) compared to other reported G. thermodenitrificans isolates. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the combination of physical and chemical pretreatments of wheat bran (WB) and oat hulls (OH) to obtain fermentable sugars and a residual solid fraction with increased susceptibility to enzymatic hydrolysis. High-pressure steam in an autoclave and ultrasonication were employed as pretreatments, and for both processes, WB and OH were treated with sulfuric acid (H2SO4), neutral medium (H2O) and sodium hydroxide (NaOH). Autoclave high-pressure steam in an acid medium was the most effective for the release of sugars (total sugars, xylose and glucose) from liquid hydrolysates and for the modification of the residual solid fraction. The cellulose content of the WB residual solid fraction increased from 7.19 to 39.17%, the lignin fraction of WB decreased from 6.40 to 3.21%, the cellulose content of OH increased from 31.16 to 61.53%, and lignin fraction of OH decreased from 18.12 to 7.24%, resulting in materials more susceptible to enzymatic hydrolysis. [ABSTRACT FROM AUTHOR]

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The industry of mushroom cultivation uses a wide variety of lignocellulosic waste and is considered a very efficient way to recycle agro-residues and to produce food. This activity generates tons of spent mushroom substrate (SMS) every year, causing a significant disposal challenge. The SMS is a useful resource for the generation of biogas, since raw material is digested by the metabolism of fungi, performing as a pre-treatment, thus facilitating the subsequent anaerobic digestion and increasing the yield of methane production. Forty-one species of fungi have been used as pre-treatment in different types of residues; among them, 13 were cultivated mushrooms. The potential production of methane using SMS pre-treated with cultivated mushrooms should be added to the list of other common residues used, such as food/vegetable waste and pig manure. Biogas can be used as fuel, and the residues from biogas can be used as fertilizers for food crops. These productive activities can be integrated in a virtuous circle of reuse of organic resources; in which the waste of one activity is used as a substrate for another activity. Given the huge amount of SMS produced, we propose to integrate it into a virtuous circle of resource reutilization for energy generation, particularly as a viable substrate for biogas generation. Unlabelled Image • Mushrooms can grow on several lignocellulosic residues from agroindustry. • Spent mushroom substrate can be used to produce high yields of biogas. • Fungi act as a pre-treatment for raw material prior to anaerobic digestion. • Integration of SMS to a virtuous circle of quality products and residue reutilization [ABSTRACT FROM AUTHOR]

In this paper presents a simulation model of the fermentation/separation process of bioethanol from hydrolyzed pretreated rice husk, using Aspen HYSYS simulator. Sensitivity studies performed on the developed model indicated levels for selected variables: biomass/water ratio of 1:2,89 ; biomass flow of 50 t/h and inlet temperature separator of 30°C, leading to maximize the yield of bioethanol. From these variables, a bioethanol production of 8,81 t/h with a purity of 65,51% w/w is obtained, corresponding to a flow of hydrolyzed treated biomass of 50 t/h. This work represents an advance in the development of the simulation model of the complete process to obtain second generation of bioethanol from rice husks.

Microbial lipid production using renewable raw material is considered an alternative for biodiesel production. In this study, several biotopes have been targeted for new oleaginous yeasts isolation. 205 yeast strains were screened to find efficient and more suitable oleaginous yeasts for agro-industrial wastes bioconversion. Using the qualitative fluorometric technique, 12 strains were pre-selected and the morphology of their lipid bodies was studied. The molecular identification showed that our isolates are closely related to six genera of oleaginous yeast. Cultivated on nitrogen limited medium, lipid content of all yeast strains exceeds 20% (w/w), confirming their oleaginous character. The highest lipid yield and content were achieved by Candida viswanathii Y-E4 (3.55 g/L) and Rhodotorula babjevae Y-SL7 (39.17%), respectively. All the lipid profiles analyzed are mainly formed by triacylglycerols of oleic acid. In addition to the lipogenic aptitude, the hydrolytic potential including cellualse and lipase activities was also studied. The highest CMCase (0.11 U/mL) and β-glucosidase (0.55 U/mL) activities were produced by the Trichosporon asahii Y-SL1 strain. However, the highest lipase activity (50 U/mL) was detected in the liquid culture of Yarrowia lipolytica Y-D1P. To minimize the SCO production cost, oleaginous yeasts were evaluated for their capacity to use agro-industrial by-products for lipids and enzymes production. Cultivated on wheat bran acid-hydrolysate, Rhodotorula mucilaginosa Y-MG1 exhibits the highest lipid yield (2.2 g/L). In parallel, a considerable lipid content 64% (w/w) and lipase activity (174.1 U/mL) were achieved by Yarrowia lipolytica Y-D1P and Trichosporon asahii Y-D1 respectively, when the soap stock of pomace olive oil refining was used as carbon source. This study opens up new perspectives in the use of industrial wastes for production of microbial lipids and high-added value products. [ABSTRACT FROM AUTHOR]