Use of waste frying oil and coconut pulp for the production, isolation, and characterization of a new lipase from Moesziomyces aphidis.

Lipases comprise the third most commercialized group of enzymes worldwide and those of microbial origin are sought for their multiple advantages. Agro-industrial waste can be an alternative culture medium for producing lipases, reducing production costs and the improper disposal of waste frying oil (WFO). This study aimed to produce yeast lipases through submerged fermentation (SF) using domestic edible oil waste as inducer and alternative culture medium. The optimal culture conditions, most effective inducer, and purification method for a new lipase from Moesziomyces aphidis BRT57 were identified. Yeast was cultured in medium containing green coconut pulp and WFO waste for 72 h. The maximum production of lipases in SF occurred in a culture medium containing WFO and yeast extract at 48 and 72 h of incubation, with enzyme activities of 8.88 and 11.39 U mL-1, respectively. The lipase was isolated through ultrafiltration followed by size exclusion chromatography, achieving a 50.46 % recovery rate. To the best of our knowledge, this is the first study to report the production and purification of lipases from M. aphidis, demonstrating the value of frying oil as inducer and alternative medium for SF, contributing to the production of fatty acids for biodiesel from food waste.

3D-printing bauxite residue/fly ash-containing geopolymers as promising metal sorbents for water treatment.

Herein, we demonstrate for the first time the feasibility of employing significant amounts (up to 80 wt%) of unexplored industrial wastes (red mud and biomass fly ash) in the production of highly porous 3D-printed geopolymer lattices envisioned for wastewater treatment applications. This without compromising the mechanical performance of the geopolymers relative to those obtained using commercial precursors. The impact of the fly ash incorporation content in the fresh-state (calorimetric and reological characterization) and hardened-state (porosity and mechanical strength) properties of the produced structures was evaluated. Moreover, the influence of key printing parameters, including nozzle diameter and geometry alignment, on the resulting properties of the lattices was also evaluated. The most promising compositions were then evaluated as lead sorbents under continuous flow. The waste-based 3D-printed lattices showed remarkable adsorption ability reaching >95 % removal efficiency after 2 h. This sustainable strategy is in line with the United Nations sustainable development goals and the transition to a circular economy, reducing the consumption of natural resources and simultaneously contributing to reducing water pollution.

Agro-Industrial Wastes as Potential Substrates for Rhamnolipid Production by Pseudomonas aeruginosa USM-AR2.

Rhamnolipid has gained much attention in various fields owing to its distinctive functional properties compared to conventional chemical surfactants, which are mostly derived from petroleum feedstock. Production cost is one of the main challenges in rhamnolipid production, particularly when using refined substrates. One possible solution is to use agro-industrial wastes as substrates for rhamnolipid production. This is a promising strategy due to their abundance and commercially low value, while simultaneously alleviating an agro-industrial waste management problem in the environment. This study aims to evaluate agro-industrial wastes from local crops as possible low-cost alternative substrates for rhamnolipid production by a local isolate, Pseudomonas aeruginosa USM-AR2. Various liquid wastes, namely sugarcane molasses, rice washing water, overly mature coconut (OMC) water, empty fruit bunch (EFB) steam effluent, palm sludge oil (PSO) and palm oil mill effluent (POME) were screened as the main carbon source supplementing mineral salt medium (MSM) in the fermentation of P. aeruginosa USM-AR2. Batch fermentation was carried out in a shake flask system, agitated at 200 rpm and incubated at room temperature, 27 ± 2°C for 120 h. Among the substrates tested, PSO exhibited the highest biomass at 20.78 g/L and rhamnolipid production at 1.07 g/L. This study has shown the potential of agro-industrial wastes in Malaysia as an alternative resource for rhamnolipid production, transforming them into value added products, while reducing the amount of wastes discharged into the environment.

Integrating deep learning techniques for effective river water quality monitoring and management.

Effective river water quality monitoring is essential for sustainable water resource management. In this study, we established a comprehensive monitoring system along the Kaveri River, capturing real-time data on multiple critical water quality parameters. The parameters collected encompassed water contamination levels, turbidity, pH measurements, temperature, and total dissolved solids (TDS), providing a holistic view of river water quality. The monitoring system was meticulously set up with strategically positioned sensors at various river locations, ensuring data collection at regular 5-min intervals. This data was then transmitted to a cloud-based web portal, facilitating storage and analysis. To assess water quality, we introduced a novel hybrid approach, combining Convolutional Neural Networks (CNN) and Long Short-Term Memory (LSTM) networks. The proposed CNN-LSTM model achieved a validation accuracy of 98.40%, surpassing the performance of other state-of-the-art methods. Notably, the practical application of this system includes real-time alerts, promptly notifying stakeholders when water quality parameters exceed predefined thresholds. This feature aids in making informed decisions in water resource management. The study's contributions lie in its effective river water quality monitoring system, which encompassing various parameters, and its potential to positively impact environmental conservation efforts by providing a valuable tool for informed decision-making and timely interventions.

Empirical Modeling of the Drying Kinetics of Red Beetroot (Beta vulgaris L.; Chenopodiaceae) with Peel, and Flour Stability in Laminated and Plastic Flexible Packaging.

Despite the high global production of beetroot (Beta vulgaris L.), its peel is often discarded. Transforming beetroot into flour can reduce waste, improve food security, and decrease environmental pollution. However, large-scale feasibility depends on understanding drying kinetics and optimal storage conditions. This study aimed to investigate the effects of different temperatures in the convective drying of whole beetroot and evaluate the influence of laminated flexible and plastic packaging on flour stability over two months. Drying kinetics were analyzed using five models, with the Page and Logarithm models showing the best fit (R2 > 0.99). Def values (1.27 × 10-9 to 2.04 × 10-9 m2 s-1) increased with rising temperatures while drying time was reduced (from 820 to 400 min), indicating efficient diffusion. The activation energy was 29.34 KJ mol-1, comparable to other plant matrices. Drying reduced moisture and increased ash concentration in the flour. The flour showed a good water adsorption capacity and low cohesiveness, making it marketable. Laminated packaging was more effective in controlling physicochemical parameters, reducing hygroscopicity, and maintaining quality over 60 days. In summary, the Page model can predict beetroot drying kinetics effectively, and laminated packaging can control flour stability.

The Role of a New Stabilizer in Enhancing the Mechanical Performance of Construction Residue Soils.

Urban construction generates significant amounts of construction residue soil. This paper introduces a novel soil stabilizer based on industrial waste to improve its utilization. This stabilizer is primarily composed of blast furnace slag (BFS), steel slag (SS), phosphogypsum (PG), and other additives, which enhance soil strength through physical and chemical processes. This study investigated the mechanical properties of construction residue soil cured with this stabilizer, focusing on the effects of organic matter content (Oo), stabilizer dosage (Oc), and curing age (T) on unconfined compressive strength (UCS). Additionally, water stability and wet-dry cycle tests of the stabilized soil were conducted to assess long-term performance. According to the findings, the UCS increased with the higher stabilizer dosage and longer curing periods but reduced with the higher organic matter content. A stabilizer content of 15-20% is recommended for optimal stabilization efficacy and cost-efficiency in engineering applications. The samples lost their strength when immersed in water. However, adding more stabilizers to the soil can effectively enhance its water stability. Under wet-dry cycle conditions, the UCS initially increased and then decreased, remaining lower than that of samples cured under standard conditions. The findings can provide valuable data for the practical application in construction residual soil stabilization.

Conversion of acidified lignin containing sulfur discharged from a biorefinery process into neutralized biochar: Characterization and metal adsorption.

The objectives of this study were to produce biochars using sulfur-rich acidified lignin discharged from a biorefinery process and to evaluate their physicochemical properties and Pb adsorption capacity. As the pyrolysis temperature increased, the lignin acidified by the desulfurization process was converted to neutralized biochar (LBC), which exhibited high carbon content and stability. The carbon content of biochar manufactured at a pyrolysis temperature of 600 °C or higher was over 90 % and showed no significant difference, and their surface structures were found to be different, as revealed through XRD and FTIR analyses. The adsorption capacity of Pb by LBC increased with increasing pyrolysis temperature, and their adsorption capacity was well described by the pseudo-second-order model and the Langmuir isotherm adsorption model. In particular, the internal diffusion effect on the adsorption capacity of Pb was greater for LBC900 than for LBC600. In complex heavy metal solutions, LBC selectively exhibited high affinity for Pb, while the adsorption capacity of other metals was significantly reduced. The adsorption mechanism of Pb by LBC was verified through various analytical methods, and these results demonstrated that the adsorption of Pb by LBC was influenced by functional groups existing on the surface and inside of LBC and by some cation exchange.

Use of corncob and pineapple peel as associated substrates for biosurfactant production.

Biosurfactants are amphiphilic biomolecules with promising tensoative and emulsifying properties that find application in the most varied industrial sectors: environment, food, agriculture, petroleum, cosmetics, and hygiene. In the current work, a 23 full-factorial design was performed to evaluate the effect and interactions of pineapple peel and corncob as substrates for biosurfactant production by Bacillus subtilis LMA-ICF-PC 001. In a previous stage, an alkaline pretreatment was applied to corncob samples to extract the xylose-rich hydrolysate. The results indicated that pineapple peel extract and xylose-rich hydrolysate acted as partial glucose substitutes, minimizing production costs with exogenous substrates. Biosurfactant I (obtained at 8.11% pineapple peel extract, 8.11% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited a significant surface tension reduction (52.37%) and a promising bioremediation potential (87.36%). On the other hand, biosurfactant III (obtained at 8.11% pineapple peel extract, 31.89% xylose-rich hydrolysate from corncob, and 2.8109 g/L glucose) exhibited the maximum emulsification index in engine oil (69.60%), the lowest critical micellar concentration (68 mg/L), and the highest biosurfactant production (5.59 g/L). These findings demonstrated that using pineapple peel extract and xylose-rich hydrolysate from corncob effectively supports biosurfactant synthesis by B. subtilis, reinforcing how agro-industrial wastes can substitute traditional carbon sources, contributing to cost reduction and environmental sustainability.

Microbes' role in environmental pollution and remediation: a bioeconomy focus approach.

Bioremediation stands as a promising solution amid the escalating challenges posed by environmental pollution. Over the past 25 years, the influx of synthetic chemicals and hazardous contaminants into ecosystems has required innovative approaches for mitigation and restoration. The resilience of these compounds stems from their non-natural existence, distressing both human and environmental health. Microbes take center stage in this scenario, demonstrating their ability of biodegradation to catalyze environmental remediation. Currently, the scientific community supports a straight connection between biorefinery and bioremediation concepts to encourage circular bio/economy practices. This review aimed to give a pre-overview of the state of the art regarding the main microorganisms employed in bioremediation processes and the different bioremediation approaches applied. Moreover, focus has been given to the implementation of bioremediation as a novel approach to agro-industrial waste management, highlighting how it is possible to reduce environmental pollution while still obtaining value-added products with commercial value, meeting the goals of a circular bioeconomy. The main drawbacks and challenges regarding the feasibility of bioremediation were also reported.

Production of milk-coagulating protease by fungus Pleurotus djamor through solid state fermentation using wheat bran as the low-cost substrate.

Proteases are enzymes that hydrolyze peptide bonds present in proteins and peptides. They are widely used for various industrial applications, such as in the detergent, food, and dairy industries. Cheese is one of the most important products of the dairy industry, and the coagulation stage is crucial during the cheese-making process. Enzymatic coagulation is the most common technique utilized for this purpose. Microbial enzymes are frequently used for coagulation due to their advantages in terms of availability, sustainability, quality control, product variety, and compliance with dietary and cultural/religious requirements. In the present study, we identified and subsequently characterized milk coagulant activity from the fungus Pleurotus djamor PLO13, obtained during a solid-state fermentation process, using the agro-industrial residue, wheat bran, as the fermentation medium. Maximum enzyme production and caseinolytic activity occurred 120 h after cultivation. When the enzyme activity against various protease-specific synthetic substrates and inhibitors was analyzed, the enzyme was found to be a serine protease, similar to elastase 2. This elastase-2-like serine protease was able to coagulate pasteurized whole and reconstituted skim milk highly efficiently in the presence and absence of calcium, even at room temperature. The coagulation process was influenced by factors such as temperature, time, and calcium concentration. We demonstrate here, for the first time, an elastase-2-like enzyme in a microorganism and its potential application in the food industry for cheese production.

A disulfide bond mutant of Pseudoalteromonas porphyrae κ-carrageenase conferred improved thermostability and catalytic activity and facilitated its utilization in κ-carrageenan industrial waste residues recycling.

In this study, Discovery Studio was employed to predict the potential disulfide bond mutants of the catalytic domain of Pseudoalteromonas porphyrae κ-carrageenase to improve the catalytic activity and thermal stability. The mutant N205C-G239C was identified with significantly increased catalytic activity toward κ-carrageenan substrate, with activity 4.28 times that of WT. The optimal temperature of N205C-G239C was 55 °C, 15 °C higher than that of WT. For N205C-G239C, the t1/2 value at 50 °C was 52 min, 1.41 times that of WT. The microstructural analysis revealed that the introduced disulfide bond N205C-G239C could create a unique catalytic environment by promoting favorable interactions with κ-neocarratetraose. This interaction impacted various aspects such as product release, water molecule network, thermodynamic equilibrium, and tunnel size. Molecular dynamics simulations demonstrated that the introduced disulfide bond enhanced the overall structure rigidity of N205C-G239C. The results of substrate tunnel analysis showed that the mutation led to the widening of the substrate tunnel. The above structure changes could be the possible reasons responsible for the simultaneous enhancement of the catalytic activity and thermal stability of mutant N205C-G239C. Finally, N205C-G239C exhibited the effective hydrolysis of the κ-carrageenan industrial waste residues, contributing to the recycling of the oligosaccharides and perlite.

Nanocellulose from agro-industrial wastes: A review on sources, production, applications, and current challenges.

Significant volumes of agricultural and industrial waste are produced annually. With the global focus shifting towards sustainable and environmentally friendly practices, there is growing emphasis on recycling and utilizing materials derived from such waste, such as cellulose and lignin. In response to this imperative situation, nanocellulose materials have surfaced attracting heightened attention and research interest owing to their superior properties in terms of strength, stiffness, biodegradability, and water resistance. The current manuscript provided a comprehensive review encompassing the resources of nanocellulose, detailed pretreatment and extraction methods, and present applications of nanocellulose. More importantly, it highlighted the challenges related to its processing and utilization, along with potential solutions. After evaluating the benefits and drawbacks of different methods for producing nanocellulose, ultrasound combined with acid hydrolysis emerges as the most promising approach for large-scale production. While nanocellulose has established applications in water treatment, its potential within the food industry appears even more encouraging. Despite the numerous potential applications across various sectors, challenges persist regarding its modification, characterization, industrial-scale manufacturing, and regulatory policies. Overcoming these obstacles requires the development of new technologies and assessment tools aligned with policy. In essence, nanocellulose presents itself as an eco-friendly material with extensive application possibilities, prompting the need for additional research into its extraction, application suitability, and performance enhancement. This review focused on the wide application scenarios of nanocellulose, the challenges of nanocellulose application, and the possible solutions.

Role of pressmud compost for reducing toxic metals availability and improving plant growth in polluted soil: Challenges and recommendations.

Pressmud compost is an organic soil amendment and a robust technology that has potential to restore toxic metals (TMs) polluted soil. The application of organic amendments including pressmud compost in soil for toxic metals (TMs) alleviation have gained considerable attention as compared to traditional methods among the scientific community. In this review paper, we summarized the literature aiming to understand the immobilization efficacy of TMs such as cadmium, lead, chromium, copper, nickel, iron, zinc, and manganese, underlying mechanisms, plant growth, essential nutrients and soil health under pot, field and incubation conditions which has not been well investigated up-to-date. The application of pressmud compost at 10 t ha-1 rate has shown highly potential to reduce the bioavailability and bioaccumulation of TMs in the polluted soil. The immobilization mechanism of TMs in soil depends on soil pH, soil type, cation exchange capacity, hydraulic conditions, nutrients dynamics and soil properties. The application of pressmud compost integrated with biochar, compost, rock phosphate, farmyard manure, bagasse ash, molasses immobilized the cadmium, lead, copper, chromium, nickel and zinc in alkaline polluted soil, whereas pressmud compost combined with poultry manure and farmyard manure increased the bioavailability of lead, cadmium, cobalt, chromium, copper, zinc, iron and manganese in acidic soil, it could be due to aging of pressmud compost, application rate, metal type, nature of soil, particle size, application method, plant type and agronomic practices. There is a lack of knowledge on the phyto-management of arsenic, mercury and boron in soil amended with pressmud compost. Future studies must be focused on potential of pressmud compost co-amended with minerals, modified biochars and nano-material for immobilization of TMs in polluted soil-plant through machine learning/artificial intelligence in order to reduce the health risks and improve public health safety in urban and rural areas.

Assessing the impact of green patents on pollution reduction: A micro-level study of Chinese industrial firms.

As global warming and environmental degradation escalate, policymakers worldwide increasingly advocate for the development of green patents. However, there is ongoing debate regarding the effectiveness of green patents in actual pollution reduction. Some studies suggest that firms may engage in green patenting activities to align with government and market expectations rather than achieving substantive breakthroughs in pollution reduction. In light of this, it is crucial to examine the impact of green patents on pollution reduction. This study employs a PSM-DID model to analyze the impact of green patents on pollution emission intensity using plant-level data from Chinese industrial firms. The results demonstrate that with an average increase of 1% in the number of green patents, the industrial waste gas emission intensity and industrial wastewater discharge intensity decreased by 4.74% and 8.68%, respectively. Furthermore, pollution treatment facilities were found to be more effective than green patents during the sample period. On average, the contribution of waste gas treatment facilities and wastewater treatment facilities in pollution reduction is 3.33% and 9.79% higher than that of green patents. These findings suggest that firms should adopt a balanced approach when making decisions on pollution reduction. Further analysis shows that the pollution reduction effect of green patents is partly at the expense of the total factor productivity of firms. This trade-off highlights the need for policy interventions to support firms in integrating green technologies without compromising productivity. This study underscores the emphasizes of transitioning from end-of-pipe pollution control to green production processes to achieve sustainable development in China.

Sustainable route for silica preparation from silica fume.

Silica fume (SF) is a major voluminous and bulky by-product of the ferrosilicon industry, and its disposal poses a significant environmental concern. To address this issue, a sustainable approach was employed to transform SF into silica powder using a precipitation method. The process involved calcination, acid precipitation, aging, and drying, utilising industrial by-products such as silica fume and calcium oxide. Various parameters, including hydrochloric acid concentration, water bath temperature, aging pH, aging temperature, and aging time, were systematically investigated to optimise the properties of the resulting silica product. The physical and chemical attributes of the processed silica were thoroughly examined using techniques such as X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), laser particle size analysis, and dibutyl phthalate (DBP) absorption tests. Under optimal conditions (hydrochloric acid concentration of 20%, water bath temperature of 90℃, aging pH 3-4, aging temperature of 90℃, and aging time of 8 hours), the resulting silica product achieved a purity of 98.5866%, a DBP absorption value of 2.85 mL/g, and a particle size of 6.07 µm, meeting national industry standards. This environmentally benign and cost-efficient synthesis route offers a practical solution for large-scale production.

Exploring the biological activities and potential therapeutic applications of agro-industrial waste products through non-clinical studies: A systematic review.

The latent potential of active ingredients derived from agro-industrial waste remains largely untapped and offers a wealth of unexplored resources. While these types of materials have applications in various fields, their ability to benefit human health needs to be further explored and investigated. This systematic review was conducted to systematically evaluate non-clinical studies that have investigated the biological effects of fractions, extracts and bioactive compounds from agro-industrial wastes and their potential therapeutic applications. Articles were selected via PubMed, Embase and Medline using the descriptors (by-products[title/abstract]) AND (agro-industrial[title/abstract]). The systematic review was registered in the International Prospective Register of Systematic Reviews (Prospero) under the number CRD42024491021. After a detailed analysis based on inclusion and exclusion criteria, a total of 38 articles were used for data extraction and discussion of the results. Information was found from in vitro and in vivo experiments investigating a variety of residues from the agro-industry. The studies investigated peels, pomace/bagasse, pulp, seeds, aerial parts, cereals/grains and other types of waste. The most studied activities include mainly antioxidant and anti-inflammatory effects, but other activities such as antimicrobial, cytotoxic, antiproliferative, antinociceptive, hypoglycemic, antihyperglycemic and anticoagulant effects have also been described. Finally, the studies included in this review demonstrate the potential of agro-industrial waste and can drive future research with a focus on clinical application.

Agro-industrial Waste Utilization, Medium Optimization, and Immobilization of Economically Feasible Halo-Alkaline Protease Produced by Nocardiopsis dassonvillei Strain VCS-4.

The oceanic actinobacteria have strong potential to secrete novel enzymes with unique properties useful for biotechnological applications. The Nocardiopsis dassonvillei strain VCS-4, associated with seaweed Caulerpa scalpeliformis, was a halo-alkaline protease producer. Further investigation focuses on medium optimization and the use of agro-industrial waste for economically feasible, high-yield protease production. A total of 12 experimental runs were designed using Minitab-20 software and Placket-Burman design. Among the 7 physicochemical parameters analyzed, incubation time and gelatin were detected as significant factors responsible for higher protease production. Incubation time and gelatin were further analyzed using OVATs. Optimal protease production was achieved with 2% gelatin, 0.1% yeast extract, 0.1% bacteriological peptone, 7% NaCl, pH 8, 5% inoculum, and a 7-day incubation period, resulting in a maximum protease activity (Pmax) of 363.97 U/mL, generation time of 11.9 h, specific growth rate of 0.161 g/mL/h, and protease productivity (Qp) of 61.65 U/mL/h. Moreover, utilizing groundnut cake as an agro-industrial waste led to enhanced production parameters: Pmax of 408.42 U/mL, generation time of 9.74 h, specific growth rate of 0.361 g/mL/h, and Qp of 68.07 U/mL/h. The immobilization of crude protease was achieved using Seralite SRC 120 as a support matrix resulting in 470.38 U/g immobilization, 88.20% immobilization yield, and 28.90% recovery activity. Characterization of both crude and immobilized proteases revealed optimal activity at pH 10 and 70 °C. Immobilization enhanced the shelf-life, reusability, and stability of VCS-4 protease under extreme conditions.

A novel two stages chemical activation of pinewood waste for removing organic micropollutants from water and wastewater.

The prevalent presence of pharmaceuticals in aquatic ecosystems underscores the necessity for developing cost-effective techniques to remove them from water. The utilization of affordable precursors in producing activated carbon, capable of rivaling commercial alternatives, remains a persistent challenge. The adsorption of diclofenac and ciprofloxacin onto a novel pinewood-derived activated carbon (FPWAC) was explored, employing a sequential activation process involving ammonium nitrate (NH4NO3) treatment followed by sodium hydroxide (NaOH) activation. The produced FPWAC was then thoroughly characterized by employing several techniques. The removal of diclofenac and ciprofloxacin in water and real wastewater effluent was examined in batch tests. The optimum removal conditions were an FPWAC dosage of 1 g L-1, pH 6, mixture concentration of 25 mg L-1, and a temperature of 25 °C. The FPWAC was able to remove both pharmaceuticals for up to six cycles, with more than 95% removal for water and 90% for wastewater in the first cycle. The adsorption performance fitted well with the non-linear Freundlich isotherm for both pollutants. The kinetics of adsorption of diclofenac followed a pseudo-first-order model, while ciprofloxacin showed adherence to the pseudo-second-order model. FPWAC proved its potency as a low-cost adsorbent for pharmaceutical removal from wastewater.

Proposed simplified methodological approach for designing geopolymer concrete mixtures.

The development of geopolymer concrete offers promising prospects for sustainable construction practices due to its reduced environmental impact compared to conventional Portland cement concrete. However, the complexity involved in geopolymer concrete mix design often poses challenges for engineers and practitioners. In response, this study proposes a simplified approach for designing geopolymer concrete mixtures, drawing upon principles from Portland cement concrete mix design standards and recommended molar ratios of oxides involved in geopolymer synthesis. The proposed methodology aims to streamline the mix design process while optimizing key factors such as chemical composition, alkali activation solution, water content, and curing conditions to achieve desired compressive strength and workability. By leveraging commonalities between Portland cement concrete and geopolymer concrete, this approach seeks to facilitate the adoption of geopolymer concrete in practical construction applications. The proposed mix design guidelines have been validated through examples for concrete cured under different conditions, including outdoor and oven curing. Future research should focus on validating the proposed methodology through experimental studies and exploring cost-effective alternatives for alkali activation solutions to enhance the feasibility and scalability of geopolymer concrete production. Overall, the proposed simplified approach holds promise for advancing the utilization of geopolymer concrete as a sustainable alternative in the construction industry.

Assessment of the chemical composition of buriti (Mauritia flexuosa Liliopsida) and cassava (Manihot esculenta Crantz) residues and their possible application in the bioproduction of coconut aroma (6 pentyl-α-pyrone).

This work aimed to define strategies to increase the bioproduction of 6 pentyl-α-pyrone (bioaroma). As first strategy, fermentations were carried out in the solid state, with agro-industrial residues: Mauritia flexuosa Liliopsida. and Manihot esculenta Crantz in isolation, conducting them with different nutrient solutions having Trichoderma harzianum as a fermenting fungus. Physicochemical characterizations, centesimal composition, lignocellulosic and mineral content and antimicrobial activity were required. Fermentations were conducted under different humidification conditions (water, nutrient solution without additives and nutrient solutions with glucose or sucrose) for 9 days. Bioaroma was quantified by gas chromatography, assisted by solid-phase microextraction. The results showed the low production of this compound in fermentations conducted with sweet cassava (around 6 ppm (w/w)). The low bioproduction with sweet cassava residues can probably be related to its starch-rich composition, homogeneous substrate, and low concentration of nutrients. Already using buriti, the absence of aroma production was detected. Probably the presence of silicon and high lignin content in buriti minimized the fungal activity, making it difficult to obtain the aroma of interest. Given the characteristics presented by the waste, a new strategy was chosen: mixing waste in a 1:1 ratio. This fermentation resulted in the production of 156.24 ppm (w/w) of aroma using the nutrient solution added with glucose. This combination, therefore, promoted more favorable environment for the process, possibly due to the presence of fermentable sugars from sweet cassava and fatty acids from the buriti peel, thus proving the possibility of an increase of around 2500% in the bioproduction of coconut aroma.