Search Results (453)

Biochars are currently proposed as soil amendments or sorbent materials. There is an extensive scientific literature that deals with biochars originating from different raw materials. However, a holistic physicochemical characterization with simple analytical techniques is needed to provide insights on the characteristics of the biochars produced from malt spent rootlets (MSRs) and how they vary using different pyrolysis temperatures. This way, their properties can be fully understood, and they can be used for commercial purposes more effectively. Initially, the texture of the biochars were visualized by SEM and was quantified by the adsorption/desorption of nitrogen and the Brunauer, Emmett, and Teller (BET) equation. Additionally, the moisture content, the ash content and the pH of each sample were measured. Furthermore, the electrical conductivity of each sample was measured. Different techniques were used to determine the properties of carbon and of the surface functional groups (Total Carbon, XRD, ATR-FTIR) and leachable organic matter. Also, sorption of the methylene blue dye solution has been studied, which is an indication of mesopores for each biochar. Molasses number was also determined, as this is an indicator of macropores. Finally, the chlorine removal rate was determined for each type of biochar. The experiments marked that the change in mass of biochars has stopped after three hours at 50 °C in the drying oven. The measured moisture content ranged from 6 to 11%. The specific surface area of our materials, calculated through the BET equation, for low temperature biochars (e.g., 28 m²/g, at 350 °C), is much lower than that of high temperature pyrolyzed biochar (e.g., 286 m²/g, at 850 °C). The pH value ranged from 7 to 10. The electrical conductivity values of samples ranged from 800 μS/cm to 2.55 mS/cm, and these decreased during the measurement after the second wash with deionized water. Crystallinity increased with increasing pyrolysis temperature whereas the number of functional groups decreased. MSR biochars produced at temperatures equal or higher than 750 °C demonstrate different characteristics to the ones produced at lower temperatures. Full article

Fructooligosaccharides (FOSs) are plant-based prebiotics widely utilized in the food and pharmaceutical industries. As a major sugar-producing region, Guangxi holds significant potential for enzymatic production of FOS from sucrose. This study engineered a mutant enzyme, 142P-242K, to address the low catalytic activity characteristic of wild-type enzymes. The mutation upregulated the FOS conversion efficiency from 29 to 52%, respectively. Optimal enzymatic activity was observed at 45 °C, pH 6.0, and in the presence of 1 mM Na⁺. Mechanistic investigations revealed that modifications to the catalytic domain pocket and shifts in substrate affinity were the primary factors driving enhanced FOS production. The accumulation of 1-Kestose (GF2) was attributed to the enhanced flexibility of the 142P-242K loop, which facilitates substrate access to the active site. However, the synthesis of nystose (GF3) from GF2 is hindered by the hydrophobic nature of the active site and strong hydrogen bonds binding GF2. Comparing the enzyme’s ability to produce FOS using sugarcane juice, sugarcane molasses, and adsorption-heating sugarcane molasses, it was determined that heat-adsorbed molasses yielded the highest FOS concentration (30.77%). This study offers a practical and cost-effective strategy for enzyme modification and efficient valorization of molasses. Full article

Microbial fuel cells (MFCs) convert the chemical energy of biomass into electricity through microbially driven redox reactions. We evaluated a single-chamber, membrane-less MFC fed with sugarcane molasses and inoculated with a two-member consortium: Saccharomyces cerevisiae (glucose → ethanol fermentation) and Acetobacter aceti (ethanol → acetate oxidation). Three anode–cathode pairs were tested—bronze–Zn, copper–Zn, and graphite–Zn—across 27 units and 20 operating cycles. During ethanol oxidation, A. aceti oxidizes ethanol to acetic acid and, in our configuration, this biocatalytic step is designed to contribute electrons to the bronze, copper, or graphite anodes. These electrons, together with those generated by galvanic reactions in the electrode pair, flow through the external circuit to the zinc cathode, where oxygen reduction closes the circuit. The cells reached open-circuit potentials > 0.8 V, with performance following the hierarchy graphite–Zn > copper–Zn > bronze–Zn, consistent with the superior biocompatibility and lower corrosion of carbonaceous anodes. Multivariate analysis using PLS-SEM confirmed that redox indicators and electrode composition were strong determinants of voltage output (R² = 0.911) and demonstrated high predictive relevance (Q² = 0.906) for the voltage construct. These findings show that coupling yeast fermentation with acetic acid–bacteria oxidation enables synthetic-mediator-free electron transfer in a simple single-chamber configuration and shows that electrode material selection is a primary lever for achieving stable potentials for biomass valorization. Full article

Garlic (Allium sativum L.) is a significant crop cultivated worldwide for its culinary, nutritional, and medicinal value. This study aimed to evaluate the effects of different fertilization regimes on the bioactive compounds, antioxidant activity, nutritional value, and mineral composition of garlic. The field experiment was conducted at the Institute of Field and Vegetable Crops, in three replications. Fertilization significantly influenced the bioactive compounds, antioxidant activity, nutritional quality, and mineral composition of garlic. Cattle manure proved to be the most effective treatment, increasing protein (by approx. 5.1%), total sugars (17.9%), sucrose (24.9%), sulfur content (7.2%), total phenolics (3.1%), flavonoids (30.7%), and antioxidant activity (by 5.2–23.1% depending on the assay) compared to the control, indicating superior nutritional and functional quality. Multivariate analyses highlighted the significant impact of fertilization regimes on garlic quality, with mineral fertilizer, control (treatment without fertilizer application), and cattle manure enhancing bioactive compounds, antioxidant activity, and nutritional composition. Fertilization had limited effects on macroelements, although cattle and sheep manure increased nitrogen and sulphur contents, while molasses reduced phosphorus and potassium levels. Organic fertilization significantly modified microelement composition, with sheep manure notably increasing zinc and copper, while most fertilizers reduced boron, iron, and sodium contents compared with the control. Animal-based fertilizers, particularly cattle manure, provide a sustainable alternative to mineral fertilization, enhancing garlic’s dry matter, nutritional and bioactive compounds, and antioxidant activity. Full article

Fructooligosaccharides (FOS) represent a major source of prebiotic compounds. They are widely used in functional foods for their ability to modify intestinal microbiota in animals and humans. To address the significant issue of fructooligosaccharide production being influenced by glucose concentration, this study designed a dual-enzymatic co-catalysis system for glucose isomerase (GI) and a mutant FTase (FTase^142P-242K). This system successfully increased the FOS synthesis rate (42.31 to 55.51%, w/w). Glucose isomerase catalyzes the isomerization of glucose to fructose, and the subsequent release of fructose from the active site permits the enzyme to re-enter its catalytic cycle. The optimal conditions for catalysis were found at 45 °C, pH 5.5, and 1 mM Ba²⁺. In contrast, the optimal fermentation process was established at 25 °C and induction with 1 mM IPTG. Finally, the efficient production of FOS using low-cost byproduct molasses was achieved. Fermentation optimization of the dual-enzyme system resulted in FOS yield of 53.92% (w/w), a significant increase (44.54%, w/w) from the yield obtained using single-enzyme catalysis. Based on the research, a novel and sustainable approach for high-yield synthesis of Fructooligosaccharides involves minimizing the inhibitory effect of glucose produced during sucrose transformation. Full article

The present study explores the treatment and valorization of carbon-rich, low-cost waste streams—sugar beet molasses, expired rice, and wheat cereal hydrolysates—as substrates for submerged shake-flask cultures of edible ascomycetes (Morchella elata AMRL 63, Tuber aestivum AMRL 364) and basidiomycetes (Lentinula edodes AMRL 126, Agaricus bisporus AMRL 209) within a circular bioeconomy framework. Cultures were conducted under different C/N ratios (20 and 50) with or without the addition of olive oil or its emulsion. Among the tested species, the ascomycetes M. elata AMRL 63 and T. aestivum AMRL 364 outperformed the basidiomycetes in biomass production and substrate utilization. Supplementation with olive oil or its emulsion enhanced mycelial growth and lipid accumulation, while a higher C/N ratio (50) favored exopolysaccharide (EPS) synthesis. Lipid profiles were dominated by oleic (Δ⁹C18:1) and linoleic (Δ^9,12C18:2) acids, with greater unsaturation observed in C/N = 20 cultures. Volatile analysis revealed species-specific aroma signatures, including characteristic truffle and morel compounds. The results underscore the feasibility of using waste streams for sustainable mushroom cultivation. Full article

This study examines the traditional food exchange practice carried out between villages in the Aşağıırmaklar basin in the Ardanuç district of Artvin and villages around Ardahan during the autumn months in the context of rural sustainability, alternative economy, and livelihood strategies. The aim of the research is to reveal the structure, functioning, and sustainability of this exchange system, which has not been documented in the literature before, in its socioeconomic, cultural, and managerial dimensions. The barter practice in question involves exchanging fruits such as apples, pears, plums, and mulberries that grow naturally in the Ardanuç region, along with molasses and dried products made from them, for wheat, barley, and various animal products grown in the surrounding villages of Ardahan. The barter process operates without any official institution, written contract, or formal organization, based on reciprocity, trust, and unwritten rules. The research was structured as an interpretive case study within the framework of a qualitative research approach. Data were obtained through semi-structured in-depth interviews and field observations with five individuals actively involved in the barter process. The collected qualitative data were analyzed to reveal the analytical dimensions through which the exchange practice functions as a strategy for life and livelihood. The findings show that food exchange offers an alternative exchange mechanism that reduces food waste in rural areas and utilizes local production surpluses. Furthermore, it was found that the practice is sustained within an informal yet functional coordination structure that adapts to geographical and seasonal conditions, and is transmitted across generations through social relationships based on mutual trust. The study highlights the strategic importance of non-market exchange practices in rural areas in terms of sustainability, local economy, and community resilience. Full article

Honey authenticity is increasingly threatened by the addition of low-cost sugar syrups and substitutes, which reduce its nutritional value and market credibility. In this study, five types of Polish honeys (honeydew, forest, multifloral, nectar–honeydew, and rapeseed) were intentionally adulterated with beet syrup, beet molasses, invert syrup and artificial honey at levels of 10% and 50% (v/v). The impact of adulteration was evaluated using elemental profiling by ICP-OES combined with physicochemical analyses (water content, sugar content and electrical conductivity) and chemometric methods (PCA and HCA). Natural honeys were characterized by high K, Mg and Ca contents and low Na levels, whereas adulterants significantly altered mineral composition, leading to a marked decrease in key authenticity ratios, particularly K/Na (decreases exceeding 90% at the 50% adulteration level, with systematic shifts already observable at 10% addition). Beet molasses caused the strongest disturbances in macroelement balance, while invert syrup induced weaker effects. Adulteration also resulted in increased water content, reduced °Brix values and pronounced changes in electrical conductivity. Chemometric analysis enabled clear discrimination between natural, adulterated and sugar-based samples. The combined use of elemental ratios, physicochemical parameters and chemometrics provides a robust and sensitive approach for detecting honey adulteration and supporting authenticity control. Full article

Biofloc technology (BFT) is based on the reutilization of nitrogenous waste generated by cultured organisms through the biotransformation of these compounds primarily into microbial biomass, allowing a reduction in water exchange. The aim of this study was to evaluate BFT as a water-saving culture strategy, using two carbon sources (chancaca and molasses), and to assess its effects on water-use efficiency, growth performance, digestive enzyme activity, and physiological responses in juvenile northern river shrimp (Cryphiops caementarius). The experiment was conducted in triplicate using 400 L fiberglass tanks, with an initial stocking density of 75 shrimp m⁻² and an average individual weight of 0.85 ± 0.65 g, over a 157-day rearing period. Water quality parameters were maintained within suitable ranges throughout the study. Significant differences were observed in the composition of bacterial and plankton communities among the biofloc treatments, whereas no significant differences were detected in growth performance or digestive enzyme activities. Heat shock protein 70 (Hsp70), a stress-related biomarker indicative of physiological responses, exhibited higher levels in the biofloc treatment supplemented with molasses. Overall, BFT treatments reduced water exchange by 81.6% while maintaining comparable biological performance to the control, indicating that biofloc technology represents a water-efficient and environmentally sustainable culture approach for juvenile Cryphiops caementarius, an endemic freshwater shrimp species, particularly in water-limited regions of northern Chile. Full article

Microbial fuel cells (MFCs) have attracted increasing attention due to their potential applications in renewable energy generation, waste utilization, and biomass upgrading, offering a promising alternative to traditional fossil fuels. By directly converting carbon-rich wastes into electricity, MFCs provide a unique approach to simultaneously address energy demand and waste management challenges. This review systematically examines the effects of various carbon-rich substrates on MFC performance, including lignocellulosic biomasses, molasses, lipid waste, crude glycerol, and C1 compounds. These substrates, characterized by wide availability, low cost, and high carbon content, have demonstrated considerable potential for efficient bioelectricity generation and resource recovery. Particular emphasis is placed on the roles of microbial community regulation and genetic engineering strategies in enhancing substrate utilization efficiency and power output. Additionally, the application of carbon-rich wastes in electrode fabrication is discussed, highlighting their contributions to improved electrical conductivity, sustainability, and overall system performance. The integration of carbon-rich substrates into MFCs offers promising prospects for alleviating energy shortages, improving wastewater treatment efficiency, and reducing environmental pollution, thereby supporting the development of a circular bioeconomy. Despite existing challenges related to scalability, operational stability, and system cost, MFCs exhibit strong potential for large-scale implementation across diverse industrial sectors. Full article

Microbial fuel cells (MFCs) utilizing livestock wastewater represent a critical path toward sustainable energy and net-zero emissions. To maximize this potential, this study investigates a novel circuit configuration, integrating twin MFCs with dual supercapacitors in a closed-loop system, to enhance charge storage and electricity generation. By utilizing molasses-seawater anolytes, the study establishes a performance benchmark for optimizing energy recovery in future livestock wastewater treatment applications. The self-adjusting potential difference between interconnected MFCs is verified, and supercapacitors significantly improve energy harvesting by reducing load impedance and balancing capacitor plate charges. Voltage gain across supercapacitors exceeds that of single MFC charging, demonstrating the benefits of series integration. Experimental results reveal that catholyte properties—electrical conductivity, salinity, pH, and dissolved oxygen—strongly influence MFC performance. Optimal conditions for a neutralized anolyte (pH 7.12) include dissolved oxygen levels of 5.37–5.68 mg/L and conductivity of 24.3 mS/cm. Under these conditions, supercapacitors charged with sterile diluted seawater catholyte store up to 40% more energy than individual MFCs, attributed to increased output current. While the charge balance mechanism of supercapacitors contributes to storage efficiency, its impact is less pronounced than that of conductivity and oxygen solubility. The interplay between electrochemical activation and charge balancing enhances overall electricity harvesting. These findings provide valuable insights into optimizing MFC-supercapacitor systems for renewable energy applications, particularly in livestock wastewater treatment. Full article

Fermented forest litter (FFL) is a biofertilizer obtained by anaerobic fermentation of forest litter combined with agricultural by-products. Its production involves an initial one-month solid-state fermentation of oak litter mixed with whey, molasses and wheat bran, followed by a one-week submerged fermentation-called the “activation” phase-during which the solid FFL is fermented with sugarcane molasses diluted in water. This study aimed to evaluate the effects storage duration (6, 18 and 30 months), and temperature (ambient and 29 °C) on the activation phase. For this purpose, pH, sugar consumption and metabolite production dynamics were monitored. Under all experimental conditions, the pH dropped to values close to 3.5, sucrose was rapidly hydrolyzed, and glucose was preferentially consumed over fructose. Fructose was metabolized only after glucose was depleted, suggesting the involvement of fructophilic microorganisms. The time-course evolution of lactic acid (LA) concentration was adequately fitted by the Gompertz model (R² > 0.970). The highest LA_max concentration (6.30 g/L) and production rate (2.16 g/L·d) were obtained with FFL stored for 6 months. Acetic acid (AA) and ethanol were also detected reaching maxima values of 1.19 g/L and 0.96 g/L, respectively. Their profiles varied depending on the experimental conditions. Notably, the AA/LA ratio increased with the age of the FFL. Overall, sugar consumption and metabolite production were significantly slower at ambient temperature, than at 29 °C. These results contribute to a better understanding of the metabolic dynamics during FFL activation and highlight key parameters that should be considered to optimize future biofertilizer production processes. Full article

Phosphorus (P) is an essential nutrient in plant development, but its availability in the soil is often limited due to chemical fixation and poor solubility. This study presents the development, characterization and evaluation of a novel granular bioinoculant formulated with Aspergillus tubingensis (P-solubilizing) and Trichoderma virens (P-mineralizing) using clinoptilolite (CZ) as a carrier to improve P bioavailability. The formulation process included the evaluation of the proposed components, the standardization of conidia production in different media cultures and conditions, the elaboration and characterization of the bioinoculant and its evaluation in plants. In this study, in vitro analysis demonstrated the synergistic effect of the components, showing that in all treatments with dual inoculation and CZ, the amount of soluble phosphorus (SP) was higher than in their counterparts (from 27.8 to 36.8 mg·L⁻¹). A concentration greater than 1 × 10⁹ CFU·mL⁻¹ was obtained by standardizing the production of conidia in different media (PDA, V8-Agar and Molasses Agar), which were then used to produce granular batches containing at least 2 × 10⁷ CFU·g⁻¹. Furthermore, the size (88% of the granules measured <4.5 mm), purity (<2 CFU·g⁻¹ in 10⁻⁴ dilution), and moisture content of the prototype granules (3.3–3.8%) were confirmed to be within established international quality parameters. Plant evaluations in chili and tomato demonstrated the formulation efficacy, showing an increase in both soluble and foliar P content (with at least 30% more than controls), alongside improvements in all parameters evaluated that are related to plant growth promotion (with at least 15% more growth than controls). The development of this formulation prototype represents a focused effort toward process standardization and optimization required to validate developed formulations, thus promoting the advancement of applied biotechnology. Full article

With the rapid growth of the population and the economy, environmental and health issues caused by animal protein consumption have received increasing attention. The world urgently needs alternative proteins as a way out, and microbial proteins have tremendous potential as sustainable protein sources. In this study, Neurospora intermedia FF171 was isolated and identified from Pu-erh fermented tea. FF171 can rapidly produce substantial mycelial biomass using a sugar byproduct as a carbon source. The combination of sugarcane molasses and corn gluten meal as carbon and nitrogen sources, respectively, resulted in a dry biomass of 9.10 ± 0.20 g/L and a protein yield of 6.16 ± 0.11 g/L (67.48% protein content). FF171 exhibits genetic stability, and no mycotoxins were detected in the biomass. Furthermore, the strain’s genome was sequenced and annotated. Bioinformatics analysis, including comparison of specific sequences with reference strains in the GRAS (Generally Recognized as Safe) database, was conducted to assess potential toxicity, allergenicity, and antimicrobial resistance. The results revealed no virulence or pathogenic factors and no antibiotic resistance genes, while the risk of triggering allergic reactions was minimal. Taken together, these findings suggest that Neurospora intermedia FF171 is a safe and promising candidate for mycoprotein production, with strong potential as a future alternative protein source. Full article

Reductive soil disinfestation (RSD) is an effective approach for controlling horticultural plant diseases by improving soil properties. However, its effects on microbial communities and their functional characteristics across soil depths remain poorly researched. In this study, we evaluated the impacts of RSD using solid (rice bran, RB) and liquid (molasses, MO) organic amendments in a Fusarium-infested field. Changes in biotic and abiotic properties were examined at two soil depths (0–15 cm and 15–30 cm) and the potential of different amendments to restore microecological functions in deeper soil was assessed. Both RSD treatments alleviated soil acidification and salinization compared with the control. The absolute abundances of Fusarium oxysporum and Fusarium solani were significantly reduced under both treatments, with MO-RSD showing stronger pathogen suppression in the 15–30 cm layer. MO-RSD exerted a greater influence on microbial community structure across soil depths, resulting in bacterial-fungal co-occurrence networks with higher complexity. Metabolic activity and carbon source utilization increased significantly following both RSD treatments, with the greatest enhancement observed in the 0–15 cm layer under MO-RSD. Furthermore, MO-RSD enriched a higher diversity and abundance of beneficial microorganisms such as Bacillus, Paenibacillus, and Tumebacillus in the 0–15 cm layer, and Azotobacter, Penicillium, and Neurospora in the 15–30 cm layer. These microbes were closely associated with enhanced metabolic activity and pathogen suppression. Overall, MO-RSD established a more integrated and functionally diverse microbiota across the 0–30 soil profile, likely due to the greater permeability and mobility of liquid organic amendments in shaping deeper soil microbial communities. Full article