Fermentation

28 pages, 1598 KiB

Open AccessArticle

Development of Antimicrobial and Antioxidative Chicken Patties Using Liquid-Fermented Ganoderma lucidum and Pleurotus djamor Fruiting Body Biomass

by Nur Asyiqin Zahia-Azizan, Chong Shin Yee, Muhammad Ameer Ushidee-Radzi, Zul Ilham, Muhamad Hafiz Abd Rahim, Siva Raseetha, Nazimah Hamid, Adi Ainurzaman Jamaludin and Wan Abd Al Qadr Imad Wan-Mohtar

Fermentation 2025, 11(7), 393; https://doi.org/10.3390/fermentation11070393 (registering DOI) - 9 Jul 2025

Abstract

Medicinal mushroom production utilising rural cultivation (solid state fermentation) requires approximately six months compared to culinary mushroom production (7 days). Urban cultivation (submerged liquid fermentation) can be used as a sustainable method of producing medicinal mushroom biomass. In this study, chicken patties were [...] Read more.

Medicinal mushroom production utilising rural cultivation (solid state fermentation) requires approximately six months compared to culinary mushroom production (7 days). Urban cultivation (submerged liquid fermentation) can be used as a sustainable method of producing medicinal mushroom biomass. In this study, chicken patties were fortified with liquid-fermented Ganoderma lucidum flour (GLF) and Pleurotus djamor mushroom biomass flour (PDF) at concentrations of 3%, 6%, and 9%. These were compared to a negative control (0% mushroom flour chicken patty) and a commercial patty. Chicken patties fortified with 3% PDF and 9% GLF recorded the lowest cooking loss, at 5.55% and 10.3%, respectively. Mushroom chicken patties exhibited lower cooking losses and significant changes in colour and texture compared to control samples. Notably, 3% GLF chicken patty achieved the highest overall acceptability score of 6.55 followed by 9% PDF chicken patty (6.08) (p < 0.05). Biomass flour of liquid-fermented Ganoderma lucidum (ENS-GL) and Pleurotus djamor (ENS-PD) were extracted for their endopolysaccharide and analysed for their functional properties. All elemental, FT-IR, and NMR spectroscopy analyses revealed the existence of a comparable beta-glucan polymer structure, linkages, and absorptions when compared to the Laminarin standard. In addition, ENS-GL also proved to possess higher antimicrobial activities and significant antioxidant levels (DPPH-scavenging activity, ferric reduction potential and total phenolic content) compared to ENS-PD. Overall, this study revealed that sustainable liquid-fermented Ganoderma lucidum, a medicinal mushroom, outperformed Pleurotus djamor, a culinary mushroom, as a potential alternative flour for combating hunger in the future. Full article

(This article belongs to the Special Issue Advances in Fermented Foods and Beverages)

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15 pages, 1100 KiB

Open AccessArticle

Silage of the By-Products of Mollar de Elche and Wonderful Pomegranate Varieties Preserves Nutritional Value and Antioxidant Activity of Ruminant Feed

by Marina Galvez-Lopez, Jihed Zemzmi, Mihaela Iasmina Madalina Ilea, Francisca Hernández, Martín Rodríguez, José Ramón Díaz and Gema Romero

Fermentation 2025, 11(7), 392; https://doi.org/10.3390/fermentation11070392 - 8 Jul 2025

Abstract

The valorization of agro-industrial by-products for their use in animal feed leads to a reduction in inputs, creating the opportunity to optimize the sustainability of the agri-food chain, a priority of the SDG 2030 strategy; it also leads to a reduction in production [...] Read more.

The valorization of agro-industrial by-products for their use in animal feed leads to a reduction in inputs, creating the opportunity to optimize the sustainability of the agri-food chain, a priority of the SDG 2030 strategy; it also leads to a reduction in production costs. The objective of this study was to examine the changes that occur during the silage process of the pomegranate varieties Mollar de Elche (PDO) and Wonderful in terms of their nutritional and antioxidant characteristics for subsequent use in ruminant feed. Microsilos were created with the by-products of these two different pomegranate varieties. Two different microsilos for each variety were monitored on days 0 (raw material), 14, 35, 60, and 180. The variables studied included microbiology tracks, fermentation products, pH, dry matter (DM), macronutrient composition, organic acid and sugar contents, and antioxidant activity. The results show that, for both varieties, the silage process was successful; the stability of the fermentation process was determined by day 35, and its viability was ensured for a minimum period of 6 months. Furthermore, the nutritional characteristics of the raw material were preserved in the ensiled product. An evaluation of the total phenols and antioxidant capacity (ABTS and DPPH) showed that they remained stable throughout the monitoring period, despite the decrease in bioactive compounds (total phenols) at the end of the study period. It was concluded that silage is an effective preservation method for the by-products of Mollar de Elche and Wonderful pomegranate varieties, and its outcome presents valuable potential as a sustainable nutritional resource for ruminants. Full article

(This article belongs to the Special Issue Exploring Fermentation Strategies for the Valorization of Food By-Products and Their Bioactive Potential)

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29 pages, 3353 KiB

Open AccessArticle

A Comparative Study of the Antioxidant and Antidiabetic Properties of Fermented Camel (Camelus dromedarius) and Gir Cow (Bos primigenius indicus) Milk and the Production of Bioactive Peptides via In Vitro and In Silico Studies

by Brijesh Bhuva, Bethsheba Basaiawmoit, Amar A. Sakure, Pooja M. Mankad, Anita Rawat, Mahendra Bishnoi, Kanthi Kiran Kondepudi, Ashish Patel, Preetam Sarkar and Subrota Hati

Fermentation 2025, 11(7), 391; https://doi.org/10.3390/fermentation11070391 - 8 Jul 2025

Abstract

In this study, camel milk (CM) and Gir cow milk (GCM) were fermented through cofermentation via yeast–lactic cultures, i.e., Lacticaseibacillus rhamnosus (M9, MTCC 25516) and Saccharomyces cerevisiae (WBS2A, MG101828), and their antioxidant and antidiabetic effectiveness were studied. To optimize the growth conditions, the [...] Read more.

In this study, camel milk (CM) and Gir cow milk (GCM) were fermented through cofermentation via yeast–lactic cultures, i.e., Lacticaseibacillus rhamnosus (M9, MTCC 25516) and Saccharomyces cerevisiae (WBS2A, MG101828), and their antioxidant and antidiabetic effectiveness were studied. To optimize the growth conditions, the level of proteolysis was evaluated by exploring various inoculation levels (1.5, 2.0 and 2.5%) as well as incubation durations (0, 12, 24, 36 and 48 h). Peptides were extracted and purified through 2D gel electrophoresis as well as SDS–PAGE. Water-soluble extracts (WSEs) of ultrafiltered (UF) peptide fractions were evaluated via reversed-phase high-performance liquid chromatography (RP-HPLC) to identify the peptide segments. By applying the Peakview tool, peptide sequences obtained from liquid chromatography–mass spectrometry (LC/MS) were reviewed by comparison with those in the BIOPEP database. Furthermore, the elevated levels of TNF-α, IL-6, IL-1β and nitric oxide (NO) in RAW 267.4 cells treated with lipopolysaccharide (LPS) are considerably lower than those in cultured CM and GCM. Protein macromolecules in CMs and GCMs have been captured via confocal laser scanning microscopy (CLSM) and Fourier transform infrared (FTIR) spectroscopy both before and after fermentation. Full article

(This article belongs to the Special Issue Advances in Fermented Foods and Beverages)

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13 pages, 532 KiB

Open AccessArticle

In Vitro Fermentation Characteristics of Pelagic Sargassum for Inclusion in Integral Diets for Ruminants

by Luis Alberto Canul-Ku, Fernando Casanova-Lugo, Edgar Aguilar-Urquizo, Ingrid Valdivieso-Pérez, Darwin Arcos-Álvarez, Jorge Canul-Solís, Luis Castillo-Sánchez, Alfonso Chay-Canul, Benito Dzib-Castillo and Angel Piñeiro-Vázquez

Fermentation 2025, 11(7), 390; https://doi.org/10.3390/fermentation11070390 - 8 Jul 2025

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Abstract

Pelagic sargassum arriving in the Mexican Caribbean is a mixture of brown macroalgae containing polysaccharides, minerals, and secondary metabolites with potential in ruminant diets. The objective of the present study was to evaluate the effect of the inclusion of sargassum in integral diets [...] Read more.

Pelagic sargassum arriving in the Mexican Caribbean is a mixture of brown macroalgae containing polysaccharides, minerals, and secondary metabolites with potential in ruminant diets. The objective of the present study was to evaluate the effect of the inclusion of sargassum in integral diets (ID) on in vitro fermentation characteristics. A completely randomized design was used. The treatments were different levels of sargassum (ICD: 0%, ID10: 10%, ID20: 20% and ID30: 30%) added to a basal substrate (a mixture of Pennisetum purpureum Vc. CT-115 hay, corn, soybean, and molasses). Rumen fluid was obtained from five male lambs with a body weight of 40 ± 3 kg. In vitro gas production (IVGP) as well as dry matter degradability (DMD) and organic matter degradability (DOM) increased linearly (p < 0.0001) as the proportion of sargassum increased at 24, 48, and 72 h. Rumen fluid pH decreased (p < 0.05) with 30% inclusion at 48 h, while protozoan concentration was similar (p > 0.05) in all treatments with respect to the control at all evaluation times. These results indicate that the inclusion of pelagic sargassum in integral concentrated diets improves fermentative parameters, and its inclusion in diets for ruminants is feasible. This opens up a window of opportunity for its study as a novel additive or unconventional supplement. However, in vivo studies are necessary to rule out harmful effects on animal health and performance. Full article

(This article belongs to the Section Industrial Fermentation)

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16 pages, 726 KiB

Open AccessArticle

Incorporation of Agglomerated Spirulina platensis Powder in Yogurt: A Strategy for Enhancing Nutritional Quality and Bioactive Compounds

by Rosana Correia Vieira Albuquerque, Carlos Eduardo de Farias Silva, Margarete Cabral dos Santos Silva, Wanderson dos Santos Carneiro, Kaciane Andreola, Brígida Maria Villar da Gama, Marcos Vinicius Azevedo Figueiredo, Albanise Enide da Silva and João Victor Oliveira Nascimento da Silva

Fermentation 2025, 11(7), 389; https://doi.org/10.3390/fermentation11070389 - 8 Jul 2025

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Abstract

The incorporation of Spirulina platensis has been studied as a strategy to enrich food with bioactive compounds. Recent studies have expanded the use of Spirulina in yogurts, seeking to combine its nutritional value with the practicality of functional foods. This study evaluated the [...] Read more.

The incorporation of Spirulina platensis has been studied as a strategy to enrich food with bioactive compounds. Recent studies have expanded the use of Spirulina in yogurts, seeking to combine its nutritional value with the practicality of functional foods. This study evaluated the physicochemical and bioactive compounds characteristics of yogurt incorporating commercial and agglomerated (with 30% maltodextrin, efficient carrier agent, in a fluidized bed) Spirulina platensis powder, at concentrations of 0.5–2.0% (w/v) prior to fermentation. This study is novel as it is the first to report the incorporation of S. platensis agglomerated in a fluidized bed into yogurt. Fermentations were carried out at 42 °C for 5 h and then the stirred yogurts were stored at 4 °C for 28 days for stabilization. All yogurts obtained achieved characteristic values according to the Brazilian Normative Instruction 46/2007 with total acidity (0.6–1.5%), pH (3.5–4.6), and viable lactic bacteria of at least 10⁶ CFU.g⁻¹, without significantly affecting the quality of the final product or the activity of lactic acid bacteria. For the nutritional composition, it was observed that the greater the amount of cyanobacteria incorporated, the higher the concentrations of proteins (4.2–5.6%) and ashes (1.3–1.8%) in the product, and for the bioactive compounds, the phenolic compounds ranged between 2.98 and 14.96 mg.100 g⁻¹ and significantly enriched the yogurt with phycocyanin (2.19–3.65 mg.100 g⁻¹), β-carotene (4.73–6.37 mg.100 g⁻¹), and chlorophyll a (12.39–13.77 mg.100 g⁻¹), for the formulations using commercial and agglomerated S. platensis powder. Agglomeration improved the stability of bioactive compounds after fermentation and stabilization processes of the yogurts. Also, it was found that the agglomerated S. platensis powder preserved a higher amount of bioactive compounds in the yogurt, which fulfills one of the main objectives of incorporating this cyanobacterium. Full article

(This article belongs to the Special Issue Cyanobacteria and Eukaryotic Microalgae)

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15 pages, 4580 KiB

Open AccessArticle

Correlation Analysis Between Volatile Flavor Compounds and Microbial Communities During the Fermentation from Different Ages Mud Pits of Wuliangye Baijiu

by Yanping Lu, Yalan Li, Bing Wan, Yuzhu Li, Jian Su, Jia Zheng, Dong Zhao and Yan Xu

Fermentation 2025, 11(7), 388; https://doi.org/10.3390/fermentation11070388 - 8 Jul 2025

Viewed by 73

Abstract

The continuous usage years of mud pits significantly impact the formation of volatile flavor compounds (VFCs) in Wuliangye Baijiu fermentation, yet their role in regulating initial microbial diversity and VFCs during fermentation remains unclear. This research analyzed the dynamic relationships among microorganisms, physicochemical [...] Read more.

The continuous usage years of mud pits significantly impact the formation of volatile flavor compounds (VFCs) in Wuliangye Baijiu fermentation, yet their role in regulating initial microbial diversity and VFCs during fermentation remains unclear. This research analyzed the dynamic relationships among microorganisms, physicochemical characteristics, and VFCs from two different aged mud pits (continuous usage for 20 years: JC20 and 40 years: JC40). As fermentation advanced, VFCs increased, with JC40 showing a greater increment than JC20. Furthermore, the predominated microorganisms during fermentation of two pits were significantly different, resulting in distinct microbial successions. And the microbial diversity in JC40 was higher than JC20 at the fermentation anaphase from different layers of zaopei samples. Microbes were identified that highly correlated with physicochemical properties and VFCs, and the important microbial species differed between the two pits, proving the importance of mud pit continuous usage years for Wuliangye Baijiu production. Full article

(This article belongs to the Special Issue 10th Anniversary of Fermentation: Feature Papers in the "Fermentation for Food and Beverages" Section)

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21 pages, 3887 KiB

Open AccessArticle

Biotransformation of Acetaminophen by Ganoderma parvulum Ligninolytic Enzymes Immobilized on Chitosan Microspheres

by María Alejandra Flórez-Restrepo, Xiomara López-Legarda, Magdalena de Jesús Rostro-Alanis, Roberto Parra-Saldívar and Freimar Segura-Sánchez

Fermentation 2025, 11(7), 387; https://doi.org/10.3390/fermentation11070387 - 5 Jul 2025

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Abstract

Water quality is essential for safeguarding human health and ensuring the stability of ecosystems. Nonetheless, the rising prevalence of emerging contaminants, particularly pharmaceutical compounds, has raised serious environmental concerns due to their bioactivity, widespread use, persistence, and potential toxicity. Among these, acetaminophen (paracetamol) [...] Read more.

Water quality is essential for safeguarding human health and ensuring the stability of ecosystems. Nonetheless, the rising prevalence of emerging contaminants, particularly pharmaceutical compounds, has raised serious environmental concerns due to their bioactivity, widespread use, persistence, and potential toxicity. Among these, acetaminophen (paracetamol) is one of the most frequently detected pharmaceutical pollutants in aquatic environments. Among the various degradation strategies explored, biological methods, especially those involving white-rot fungi, have shown substantial promise owing to their production of ligninolytic enzymes capable of degrading complex pollutants. This study investigates the use of laccases from Ganoderma parvulum, covalently immobilized on chitosan microspheres, for acetaminophen degradation. The immobilization involved a 10% crosslinking agent, 60-min crosslinking time, and 10,000 U/L enzyme concentration, resulting in an immobilization efficiency of 123%, 203%, and 218%, respectively. The immobilized enzymes displayed enhanced stability across pH 3–8 and temperatures between 20 and 60 °C. Biodegradation assays achieved 97% acetaminophen removal within four hours. Nuclear Magnetic Resonance (¹H NMR and COSY) confirmed structural transformation. The enzymes also retained over 95% catalytic activity after multiple reuse cycles. These findings highlight the novel application of laccases as efficient and reusable biocatalysts for pharmaceutical pollutant removal, providing valuable insights into the mechanisms of enzymatic environmental remediation. Full article

(This article belongs to the Special Issue Application of Fungi in Bioconversions and Mycoremediation)

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24 pages, 6167 KiB

Open AccessArticle

Bioreactor Design Optimization Using CFD for Cost-Effective ACPase Production in Bacillus subtilis

by Xiao Yu, Kaixu Chen, Chunming Zhou, Qiqi Wang, Jianlin Chu, Zhong Yao, Yang Liu and Yang Sun

Fermentation 2025, 11(7), 386; https://doi.org/10.3390/fermentation11070386 - 4 Jul 2025

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Abstract

Acid phosphatase (ACPase) is an essential industrial enzyme, but its production via recombinant bacterial fermentation is often limited by insufficient dissolved oxygen control. This study optimized the aerobic fermentation of the ACPase-producing recombinant bacterium Bacillus subtilis 168/pMA5-Acp by refining the bioreactor’s aerodynamic [...] Read more.

Acid phosphatase (ACPase) is an essential industrial enzyme, but its production via recombinant bacterial fermentation is often limited by insufficient dissolved oxygen control. This study optimized the aerobic fermentation of the ACPase-producing recombinant bacterium Bacillus subtilis 168/pMA5-Acp by refining the bioreactor’s aerodynamic structure using computational fluid dynamics (CFD) simulations. This was combined with fermentation kinetics modeling to achieve precise process control. First, the gas distributor structure of the 5 L bioreactor was optimized using CFD simulation results. Optimal mass transfer conditions were identified through comprehensive analysis of K_La in different reactor regions (aeration ratio: 1.142 VVm, K_La = 264.2 h⁻¹). The simulation results showed that the optimized oxygen transfer efficiency increased 2.49 fold compared to the prototype. Second, the process control issue was addressed by developing a BP (backpropagation) neural network model to predict K_La under alternative media conditions. The prediction error was less than 5%, and the model was combined with the logistic equation to construct the bacterial growth kinetic model (R² > 0.99). The experiments demonstrated that using the optimized reactor with a molasses–urea medium (molasses 7.5 g/L; urea 15 g/L; K₂HPO₄ 1.2 g/L; MgSO₄·7H₂O 0.25 g/L) reduced production costs while maintaining enzyme activity (215.99 U/mL) and biomass (OD₆₀₀ = 101.67) by 90.03%. This study provides an efficient and cost-effective process solution for the industrial production of ACPase and a theoretical foundation for bioreactor design and scale-up. Full article

(This article belongs to the Special Issue Applied Microorganisms and Industrial/Food Enzymes, 2nd Edition)

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12 pages, 1457 KiB

Open AccessArticle

Neuroprotective Effect of Lactobacillus gasseri MG4247 and Lacticaseibacillus rhamnosus MG4644 Against Oxidative Damage via NF-κB Signaling Pathway

by Ji Yeon Lee, Ju Hui Kim, Jeong-Yong Park, Byoung-Kook Kim, Ho Jin Heo and Soo-Im Choi

Fermentation 2025, 11(7), 385; https://doi.org/10.3390/fermentation11070385 - 3 Jul 2025

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Abstract

Probiotics have recently gained attention as modulators of the gut–brain axis in neurodegenerative diseases such as Alzheimer’s disease. In this study, we identified probiotic strains with neuroprotective effects and investigated their mechanisms and safety. We screened strains based on their ability to inhibit [...] Read more.

Probiotics have recently gained attention as modulators of the gut–brain axis in neurodegenerative diseases such as Alzheimer’s disease. In this study, we identified probiotic strains with neuroprotective effects and investigated their mechanisms and safety. We screened strains based on their ability to inhibit acetylcholinesterase (AChE) activity and protect cells against H₂O₂-induced damage. The cell-free supernatants (CFS) of Lactobacillus gasseri MG4247 and Lacticaseibacillus rhamnosus MG4644 inhibited AChE activity and reduced cell damage and reactive oxygen species generation. These effects were mediated through inhibition of the MyD88/NF-κB pathway and modulation of the JNK/Bax-dependent apoptotic pathway in neuronal cells treated with H₂O₂. Whole-genome sequencing and antibiotic susceptibility testing confirmed the identity and safety of both strains. These findings suggest that MG4247 and MG4644, as probiotics, may help protect neuronal cells from oxidative stress and inflammation. Full article

(This article belongs to the Special Issue Lactic Acid Bacteria: Evaluation of Benefits on Human Health and Improvement of Food Safety)

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16 pages, 1392 KiB

Open AccessArticle

Bioprospecting for a Wild Strain of Sporisorium scitamineum for the Valorization of Sugarcane Molasses into Mannosylerythritol Lipids and Cellobiose Lipids

by André D. Valkenburg, Breyten van der Merwe, George M. Teke, Eugéne van Rensburg and Robert W. M. Pott

Fermentation 2025, 11(7), 384; https://doi.org/10.3390/fermentation11070384 - 3 Jul 2025

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Abstract

Significant wastes such as bagasse, molasses, and vinasses are produced during sugarcane processing. Due to their high sugar content, these wastes are commonly used as low-cost substrates for biofuel production. However, these substrates are also suitable for the microbial synthesis of high-value biochemicals [...] Read more.

Significant wastes such as bagasse, molasses, and vinasses are produced during sugarcane processing. Due to their high sugar content, these wastes are commonly used as low-cost substrates for biofuel production. However, these substrates are also suitable for the microbial synthesis of high-value biochemicals like biosurfactants. Sporisorium scitamineum, a smut fungus capable of growing on sugarcane residues and producing mannosylerythritol lipids (MELs) and cellobiose lipids (CBLs), was identified as a promising candidate for valorizing sugarcane wastes. This study investigated MEL and CBL co-production from pure sugars and sugarcane molasses using an S. scitamineum strain isolated from sugarcane residues originating from KwaZulu-Natal, South Africa. Among the sugars tested, sucrose supported the highest glycolipid production, yielding 0.24 g/L MELs and 2.73 g/L CBLs. Lower titers were achieved with fructose, and no production occurred with glucose. Sugarcane molasses also proved to be an effective substrate, yielding 1.46 g/L CBLs—the highest reported titer from an industrial waste to date. However, all titers remained far below those of other glycolipids, which consistently exceed 50 g/L. Future efforts should focus on enhancing CBL production through process optimization or genetic engineering. Full article

(This article belongs to the Special Issue Scale-Up Challenges in Microbial Fermentation)

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13 pages, 1661 KiB

Open AccessArticle

Optimization of the Inorganic Salts in Coenzyme Q₁₀ Fermentation Medium of Rhodobacter sphaeroides Based on Uniform Design and Artificial Neural Network and Genetic Algorithm

by Yi Zheng, Yujun Xiao, Shuling Tang, Junpeng Li, Yingzi Wu and Yong Zhou

Fermentation 2025, 11(7), 383; https://doi.org/10.3390/fermentation11070383 - 2 Jul 2025

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Abstract

Coenzyme Q₁₀ (CoQ₁₀) has attracted widespread attention in recent years due to its momentous physiological functions. Microbial fermentation is the major method in CoQ₁₀ industrial production, and Rhodobacter sphaeroides is the main strain for the production of CoQ₁₀ [...] Read more.

Coenzyme Q₁₀ (CoQ₁₀) has attracted widespread attention in recent years due to its momentous physiological functions. Microbial fermentation is the major method in CoQ₁₀ industrial production, and Rhodobacter sphaeroides is the main strain for the production of CoQ₁₀ by fermentation. Optimization of the culture medium is a popular solution to improve the metabolite production. Culture medium is the material basis for microbial growth and product synthesis, of which inorganic salts are a key ingredient. Uniform design (UD), artificial neural network (ANN), and genetic algorithm (GA) are the main research methods. Through uniform design (UD) and artificial neural network/genetic algorithm (ANN-GA) progressive optimization, an optimal formulation of the inorganic salts in fermentation medium was obtained (g·L⁻¹): MgSO₄ 12, NaCl 2.5, FeSO₄ 1.6, KH₂PO₄ 0.8, MnSO₄ 0.1, CaCl₂ 0.1. Ultimately, the fermentation yield of CoQ₁₀ could reach 255.36 mg·L⁻¹. ANN-GA exhibited a superior prediction capability compared to UD. Compared to UD, the optimization results of ANN-GA had a smaller relative error (ANN-GA 1.23%; UD 3.01%) and a higher increase rate in the fermentation level of CoQ₁₀ (ANN-GA 4.1%; UD 2.04%). R. sphaeroides had a high demand for Mg²⁺. Full article

(This article belongs to the Section Industrial Fermentation)

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14 pages, 1154 KiB

Open AccessArticle

Biotechnological Valorization of Brewer’s Spent Grain from Old Bread and Barley Malt: Fermentative Potential of Saccharomyces cerevisiae

by Anita Lalić, Jolita Jagelavičiūtė, Zorana Trivunović, Marina Marić, Andrea Karlović and Loreta Bašinskienė

Fermentation 2025, 11(7), 382; https://doi.org/10.3390/fermentation11070382 - 2 Jul 2025

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Abstract

Brewer’s spent grain (BSG), the most abundant by-product from breweries, is mainly discarded or used as animal feed. However, to increase the brewing sustainability, biotechnological utilization of BSG is a much preferred solution. This study examined the fermentation of BSG, composed of old [...] Read more.

Brewer’s spent grain (BSG), the most abundant by-product from breweries, is mainly discarded or used as animal feed. However, to increase the brewing sustainability, biotechnological utilization of BSG is a much preferred solution. This study examined the fermentation of BSG, composed of old wheat bread and barley malt, by metabolic activity of Saccharomyces cerevisiae on both hydrolyzed and non-hydrolyzed media. Enzymatic hydrolysis with Viscozyme^® W FG for 6 h was selected as the most effective and was used in the further research step to prepare the hydrolyzed BSG-based medium. Both media supported almost uniform yeast growth (numbers of S. cerevisiae cells was about 8 log₁₀ CFU/g) in an acidic environment (pH value was about 5), but fermentation of hydrolyzed BSG resulted in 20% higher sugar consumption and 10% higher total titratable acidity. These findings underscore the potential of enzymatic pretreatment to improve fermentation performance. The adaptability of S. cerevisiae and the fermentability of both substrates suggest promising potential for scalable BSG valorization strategies in circular food systems. Full article

(This article belongs to the Special Issue Wine and Beer Fermentation, 2nd Edition)

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35 pages, 3044 KiB

Open AccessReview

Tools for Enhancing Extracellular Electron Transfer in Bioelectrochemical Systems: A Review

by Kaline Araújo Soares, Jhoni Anderson Schembek Silva, Xin Wang, André Valente Bueno and Fernanda Leite Lobo

Fermentation 2025, 11(7), 381; https://doi.org/10.3390/fermentation11070381 - 30 Jun 2025

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Abstract

Microbial Electrochemistry Technology (MET) leverages the unique process of extracellular electron transfer (EET) between electroactive bacteria (EAB) and electrodes to enable various applications, such as electricity generation, bioremediation, and wastewater treatment. This review highlights significant advancements in EET mechanisms, emphasizing both outward and [...] Read more.

Microbial Electrochemistry Technology (MET) leverages the unique process of extracellular electron transfer (EET) between electroactive bacteria (EAB) and electrodes to enable various applications, such as electricity generation, bioremediation, and wastewater treatment. This review highlights significant advancements in EET mechanisms, emphasizing both outward and inward electron transfer pathways mediated by diverse electroactive microorganisms. Notably, the role of electron shuttles, genetic modifications, and innovative electrode materials are discussed as strategies to enhance EET efficiency. Recent studies illustrate the importance of redox-active molecules, such as flavins and metal nanoparticles, in facilitating electron transfer, while genetic engineering has proven effective in optimizing microbial physiology to boost EET rates. The review also examines the impact of electrode materials on microbial attachment and performance, showcasing new composites and nanostructures that enhance power output in microbial fuel cells. By synthesizing the recent findings and proposing emerging research directions, this work provides an overview of EET enhancement strategies, aiming to inform future technological innovations in bioelectrochemical systems (BESs). Full article

(This article belongs to the Special Issue Microbial Fuel Cell Advances)

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18 pages, 675 KiB

Open AccessArticle

Effects of Hyperbaric Micro-Oxygenation on the Color, Volatile Composition, and Sensory Profile of Vitis vinifera L. cv. Monastrell Grape Must

by Antonio José Pérez-López, Luis Noguera-Artiaga, Patricia Navarro, Pablo Mompean, Alejandro Van Lieshout and José Ramón Acosta-Motos

Fermentation 2025, 11(7), 380; https://doi.org/10.3390/fermentation11070380 - 30 Jun 2025

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Abstract

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. [...] Read more.

Color, aroma, and overall sensory quality in red wines are largely influenced by oxygen availability during fermentation. This study evaluated the effects of micro-oxygenation under hyperbaric conditions on the physicochemical, chromatic, volatile, and sensory properties of Vitis vinifera L. cv. Monastrell grape must. Grape clusters were manually harvested and fermented under controlled conditions, applying micro-oxygenation treatments at two fermentation stages (day 3 and day 13) within a hyperbaric chamber. Physicochemical analyses, CIELab color measurements, visible reflectance spectra, GC-FID volatile profiling, and descriptive sensory analysis were performed. Micro-oxygenated samples (M1_MOX and M2_MOX) showed significant increases in lightness (L*), redness (a*), chroma (C*), and reflectance in the 520–620 nm range, indicating enhanced extraction and stabilization of phenolic pigments. Volatile analysis revealed that these samples also contained higher concentrations of key esters and terpenes associated with fruity and floral notes. Sensory evaluation confirmed these findings, with MOX-treated wines displaying greater aromatic intensity, flavor persistence, and varietal character. Control samples (M1_CON and M2_CON) exhibited lower color saturation and volatile compound content, along with diminished sensory quality. These results suggest that hyperbaric micro-oxygenation is an effective strategy for improving color intensity and aromatic complexity during red wine fermentation under controlled, non-thermal conditions. Full article

(This article belongs to the Special Issue Innovative Strategies for the Management of Wine Fermentations: 2nd Edition)

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13 pages, 465 KiB

Open AccessArticle

Seaweed (Laminaria digitata) and Honey Kombucha: A Fermented Antioxidant-Rich Beverage

by Anastasia Karpova, Deborah Adesina, Furong Tian and Azza Silotry Naik

Fermentation 2025, 11(7), 379; https://doi.org/10.3390/fermentation11070379 - 30 Jun 2025

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Abstract

Kombucha is a sweetened tea infusion fermented using a symbiotic culture of bacteria and yeast (SCOBY). Recently, kombucha has gained popularity due to its potential health benefits, attributed to its high antioxidant and probiotic properties. The aim of this research was to formulate [...] Read more.

Kombucha is a sweetened tea infusion fermented using a symbiotic culture of bacteria and yeast (SCOBY). Recently, kombucha has gained popularity due to its potential health benefits, attributed to its high antioxidant and probiotic properties. The aim of this research was to formulate a novel antioxidant-rich beverage with symbiotic benefits by utilizing ingredients such as Laminaria digitata (brown seaweed), cinnamon, and lavender adjuncts, alongside alternative substrates like acacia honey and conventionally used ingredients such as ginger (Zingiber officinale Roscoe). This study comprehensively evaluated parameters including pH levels, acidity, alcohol content, color, and antioxidant potential of the beverages. All kombucha beverages exhibited significantly high antioxidant potential levels, particularly in Honey Kombucha (HK) samples, which ranged between 164.44 and 164.78% 2,2-Diphenyl-1-picrylhydrazyl (DPPH) inhibition, and 155.44–155.29 µg Trolox Equivalent (TE)/mL for the Ferric-reducing antioxidant power (FRAP) assay on days 3 and 7. Sugar Kombucha Seaweed (SKS) and Sugar Kombucha Cinnamon (SKC) samples received the highest acceptability for flavor from the sensory panel, with scores of 87.5% and 70%, respectively. However, Honey Kombucha Ginger (HKG) received the lowest acceptability with only 12.5%. The added adjuncts and substrates significantly influenced the antioxidant potential compared to plain unfermented tea (PT). This research paper outlines well-characterized fermentation process for formulating health-promoting beverages utilizing locally sourced ingredients. Full article

(This article belongs to the Special Issue Recent Advances in Microbial Fermentation in Foods and Beverages)

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20 pages, 789 KiB

Open AccessReview

The Metabolites Produced by Lactic Acid Bacteria and Their Role in the Microbiota–Gut–Brain Axis

by Yulma Lizbeth Aguirre-Garcia, Neftiti Carolina Cerda-Alvarez, Rosa María Santiago-Santiago, Adriana Rocío Chantre-López, Sarahi Del Carmen Rangel-Ortega and Raúl Rodríguez-Herrera

Fermentation 2025, 11(7), 378; https://doi.org/10.3390/fermentation11070378 - 30 Jun 2025

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Abstract

Lactic acid bacteria (LAB) have historically been used in fermentation processes, playing a key role in the development of foods with health benefits. Understanding the factors that affect LAB functionality is essential for optimizing their application. During fermentation processes, LAB produce different metabolites [...] Read more.

Lactic acid bacteria (LAB) have historically been used in fermentation processes, playing a key role in the development of foods with health benefits. Understanding the factors that affect LAB functionality is essential for optimizing their application. During fermentation processes, LAB produce different metabolites of interest, such as lactic acid, gamma-aminobutyric acid (GABA), and short-chain fatty acids, whose production is influenced by conditions such as temperature and pH. Although LAB exhibit optimal growth ranges, their ability to adapt to moderate variations makes them particularly valuable in various applications. Currently, the impact of these LAB metabolites on human physiology is being actively investigated, especially for modulation of the Microbiota–Gut–Brain axis. Certain compounds derived from LAB have been shown to contribute to neurological, immunological, and metabolic processes, opening new perspectives for the design of functional foods. This article provides a comprehensive overview of the importance of lactic acid bacteria in human health and highlights their potential for the development of innovative strategies to promote well-being through diet. Full article

(This article belongs to the Special Issue Feature Review Papers in Microbial Metabolism, Physiology & Genetics, 2nd Edition)

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19 pages, 1443 KiB

Open AccessReview

Impact of Spontaneous Fermentation on the Physicochemical and Sensory Qualities of Cacao

by Lucas Fernando Quintana-Fuentes, Alberto García-Jerez, Ana Carolina Rodríguez-Negrette, Nurys Tatiana Hoyos-Merlano and Armando Alvis-Bermúdez

Fermentation 2025, 11(7), 377; https://doi.org/10.3390/fermentation11070377 - 30 Jun 2025

Viewed by 248

Abstract

Fermentation is a fundamental technique that allows us to obtain high-quality cacao beans and derived products. Therefore, it is necessary to apply fermentation correctly to maximize product quality. Fermentation techniques vary by region and include piles, trays, wooden boxes, baskets, and platforms. During [...] Read more.

Fermentation is a fundamental technique that allows us to obtain high-quality cacao beans and derived products. Therefore, it is necessary to apply fermentation correctly to maximize product quality. Fermentation techniques vary by region and include piles, trays, wooden boxes, baskets, and platforms. During these processes, several factors influence the physicochemical and sensory characteristics of cacao beans. The factors that influence these characteristics are the frequency of turning, the genotype of the bean, and the duration of fermentation. This review aims to explore how the fermentation method, turning frequency, bean genotype, and fermentation duration affect the physicochemical and sensory qualities of cacao beans. To this end, an exhaustive search for recent information on the most commonly used fermentation methods in cacao-producing countries over the last 10 years was carried out. The fermentation method in wooden boxes or crates is the most commonly used method worldwide. The most common turning frequency is 24 or 48 h, which is considered the most suitable time for obtaining cacao beans with better sensory attributes, such as floral and fruity aromas, and a lower level of acidity. Finally, a relationship was found between the genotype and the optimal fermentation time of cacao: about 4 days for Criollo cacao, approximately 5 days for Forastero cacao and between 1.5 and 10 days for Trinitario cacao. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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27 pages, 2941 KiB

Open AccessReview

Valorization of Fruit Pomace by Enzymatic Treatment and Microbial Fermentation

by Nadiya Samad, Clinton E. Okonkwo, Mutamed Ayyash, Ali H. Al-Marzouqi, Oni Yuliarti and Afaf Kamal-Eldin

Fermentation 2025, 11(7), 376; https://doi.org/10.3390/fermentation11070376 - 29 Jun 2025

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Abstract

Fruit pomace is a major processing byproduct abundant in fermentable sugars, dietary fibers, and phenolic and other bioactive compounds. This review provides a summary of the latest developments in fruit pomace enzymatic valorization and microbial fermentation, focusing on the enzymes and microbes used, [...] Read more.

Fruit pomace is a major processing byproduct abundant in fermentable sugars, dietary fibers, and phenolic and other bioactive compounds. This review provides a summary of the latest developments in fruit pomace enzymatic valorization and microbial fermentation, focusing on the enzymes and microbes used, technologies, bioconversion products, and applications. The extraction and structural transformation of dietary fibers, oligosaccharides, and phenolic and other bioactive compounds have been made easier by enzymatic treatments. Microbial fermentation of fruit pomace produces a range of compounds such as prebiotics, organic acids, and polyphenols. Solid-state fermentation and enzyme immobilization allow the scalability and efficiency of these processes. The combination of enzymatic valorization and microbial fermentation may provide a sustainable approach to turn fruit pomace from waste into value-added food ingredients. Full article

(This article belongs to the Special Issue Advances in Fermented Fruits and Vegetables)

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13 pages, 2967 KiB

Open AccessArticle

Production, Purification, and Application of a Biomolecule with Herbicidal Activity Produced by Fusarium fujikuroi in Submerged Cultivation

by Silvana Schmaltz, Clair Walker, Keli Souza da Silva, Renata Gulart Ninaus, Cláudia Braga Dutra, Luiza Andrea Schmidt, Gilson Zeni and Marcio Antonio Mazutti

Fermentation 2025, 11(7), 375; https://doi.org/10.3390/fermentation11070375 - 29 Jun 2025

Viewed by 138

Abstract

This study investigated the production, purification, and evaluation of a microbial metabolite with herbicidal activity produced by Fusarium fujikuroi via submerged fermentation. The purified compound (PC) was obtained through organic solvent extraction and chromatographic purification, and assessed in bioassays using Raphanus sativus and [...] Read more.

This study investigated the production, purification, and evaluation of a microbial metabolite with herbicidal activity produced by Fusarium fujikuroi via submerged fermentation. The purified compound (PC) was obtained through organic solvent extraction and chromatographic purification, and assessed in bioassays using Raphanus sativus and Triticum aestivum as bioindicator plants. A concentration of 23 mg mL⁻¹ completely inhibited seed germination in 96-well plate assays, while the crude extract (EXT) and cell-free broth (CFB) allowed radicle protrusion but resulted in abnormal seedlings with chlorosis and reduced growth. Mathematical models estimated that concentrations of 16.0 mg mL⁻¹ for radish and 0.9 mg mL⁻¹ for wheat were sufficient to suppress germination with the PC. In substrate experiments, the PC at 6.4 and 64.0 mg mL⁻¹ did not inhibit germination but caused anomalies in radish and significantly reduced wheat seedling growth. In naturally infested soil, the PC maintained phytotoxicity symptoms for 21 days, and after 28 days, a concentration of 64.0 mg mL⁻¹ significantly reduced radish seedling growth. The results highlight the potential of the compound as a bioherbicide. Full article

(This article belongs to the Special Issue 10th Anniversary of Fermentation: Feature Papers in Section "Industrial Fermentation")

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21 pages, 1379 KiB

Open AccessReview

Functional Properties of Yeast Mannoproteins—Current Knowledge and Future Perspectives

by Paulina Chraniuk and Anna Bzducha-Wróbel

Fermentation 2025, 11(7), 374; https://doi.org/10.3390/fermentation11070374 - 29 Jun 2025

Viewed by 109

Abstract

Mannoproteins are structural components of the yeast cell wall exhibiting extensive functionality applicable to the food, feed, and medical industries. They are characterized mostly by immunostimulatory, prebiotic, antimicrobial, antibiofilm, antioxidant, and emulsifying properties. The bioactive properties of mannoproteins underscore their significance in functional [...] Read more.

Mannoproteins are structural components of the yeast cell wall exhibiting extensive functionality applicable to the food, feed, and medical industries. They are characterized mostly by immunostimulatory, prebiotic, antimicrobial, antibiofilm, antioxidant, and emulsifying properties. The bioactive properties of mannoproteins underscore their significance in functional food production, therapy, and animal husbandry. This review critically examines the literature on yeast mannoproteins, focusing on their chemical characteristics, biological activity, and potential applications. Considering gaps in the literature data regarding detailed chemical characterization and mechanisms of action of mannoproteins, future research should aim at precise structural analysis, particularly of mannoproteins derived from nonconventional yeast, to uncover new potential industrial and health applications. Full article

(This article belongs to the Special Issue Biotechnological and Functional/Probiotic Characteristics of Non-Conventional Yeasts in Fermented Beverages)

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16 pages, 1769 KiB

Open AccessArticle

Anaerobic Co-Digestion of Cattle Manure and Sewage Sludge Using Different Inoculum Proportions

by Caroline Carvalho Pinto, Juliana Lobo Paes, Alexia de Sousa Gomes, Daiane Cecchin, Igor Ferreira Oliva, Romulo Cardoso Valadão and Vânia Reis de Souza Sant’Anna

Fermentation 2025, 11(7), 373; https://doi.org/10.3390/fermentation11070373 - 28 Jun 2025

Viewed by 229

Abstract

Anaerobic digestion (AD) is a sustainable strategy for converting hazardous wastes into renewable energy while supporting Sustainable Development Goals (SDGs). This study aimed to evaluate the effect of inoculum on optimizing biogas production from sewage sludge (SS) and cattle manure (CM). Bench-scale digesters [...] Read more.

Anaerobic digestion (AD) is a sustainable strategy for converting hazardous wastes into renewable energy while supporting Sustainable Development Goals (SDGs). This study aimed to evaluate the effect of inoculum on optimizing biogas production from sewage sludge (SS) and cattle manure (CM). Bench-scale digesters were fed with 0, 20, and 40% inoculum prepared at a 1:3 SS:CM ratio. Substrate and digestate were analyzed for physicochemical properties, and biogas production data were fitted using nonlinear models. Kinetic parameters ranged from 0.0770 to 0.4691 L·kg⁻¹ for Y_max, from 1.0263 to 2.1343 L·kg⁻¹·week⁻¹ for μ_max, and from 0.8168 to 8.0114 weeks for λ, depending on the ratio. The 1:3 SS:CM with 40% inoculum significantly improved biogas production by reducing the lag phase and increasing weekly yield, with the Gompertz model showing the best fit to the digestion kinetics. This was particularly evident due to the favorable conditions for microbial adaptation and efficient substrate degradation. The results reinforce the concept of optimization as defined in this study, wherein the application of inoculum enhances the performance of AD by improving the physicochemical conditions of the substrate and accelerating microbial activity, thereby resulting in increased methane (CH₄) generation and overall biogas yield. Full article

(This article belongs to the Special Issue Biorefining for Biofuel Production)

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20 pages, 4797 KiB

Open AccessArticle

Effects of Recycled Biochar Addition on Methane Production Performance in Anaerobic Fermentation of Pig and Cow Manure

by Jianling Xu, Xinyu Wang, Jitian Sun, Wenqiu Zhang, Ruixiang Huang and Yue Chen

Fermentation 2025, 11(7), 372; https://doi.org/10.3390/fermentation11070372 - 28 Jun 2025

Viewed by 130

Abstract

Anaerobic fermentation has been recognized as an effective approach to harness livestock manure resources. In the present study, cow dung and pig manure were employed as fermentation substrates. These were subjected to co-fermentation experiments with sodium hydroxide-pretreated corn straw. Additionally, biochar derived from [...] Read more.

Anaerobic fermentation has been recognized as an effective approach to harness livestock manure resources. In the present study, cow dung and pig manure were employed as fermentation substrates. These were subjected to co-fermentation experiments with sodium hydroxide-pretreated corn straw. Additionally, biochar derived from artificial wetland substrate was introduced as a conditioner to investigate the impact of varying addition quantities on the pretreated anaerobic co-fermentation process. Our findings indicate that for the anaerobic co-fermentation of cow dung, an optimal addition of 4% biochar reduced the gas production cycle by 35–45%, although the total methane yield remained relatively unchanged. Conversely, in the anaerobic co-fermentation of pig manure, a 6% biochar addition proved most effective. This adjustment, while not significantly altering the gas production cycle, led to a marked increase in the total methane content, ranging from 18.53% to 150.18%. The PCA analysis results of the cow manure experimental group showed a significant positive correlation between the addition of biochar and ammonia nitrogen. For the pig manure fermentation system, the addition of biochar can increase the final methane production potential, from 47.43 mL/g VS to 122.24 mL/g VS in the P2C experimental group. Biochar mainly regulates the activity of anaerobic bacteria through changes in pH and conductivity, thereby affecting methane production. Full article

(This article belongs to the Special Issue Biogas and Biochemical Production from Anaerobic Digestion)

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20 pages, 1233 KiB

Open AccessReview

Microalgal Valorization of CO₂: A Sustainable Pathway to Biofuels and High-Value Chemicals

by Shutong Wu, Kaiyin Ye, Xiaochuan Zheng and Lei Zhao

Fermentation 2025, 11(7), 371; https://doi.org/10.3390/fermentation11070371 - 27 Jun 2025

Viewed by 142

Abstract

The escalating climate crisis and the imperative to transition from a fossil fuel-dependent economy demand transformative solutions for sustainable energy and carbon management. Biological CO₂ capture and utilization (CCU) using microalgae represents a particularly compelling approach, capitalizing on microalgae’s high photosynthetic efficiency [...] Read more.

The escalating climate crisis and the imperative to transition from a fossil fuel-dependent economy demand transformative solutions for sustainable energy and carbon management. Biological CO₂ capture and utilization (CCU) using microalgae represents a particularly compelling approach, capitalizing on microalgae’s high photosynthetic efficiency and remarkable product versatility. This review critically examines the principles and recent breakthroughs in microalgal CO₂ bioconversion, spanning strain selection, advanced photobioreactor (PBR) design, and key factors influencing carbon sequestration efficiency. We explore diverse valorization strategies, including next-generation biofuel production, integrated wastewater bioremediation, and the synthesis of value-added chemicals, underscoring their collective potential for mitigating CO₂ emissions and achieving comprehensive resource valorization. Persistent challenges, such as economically viable biomass harvesting, cost-effective scale-up, and enhancing strain robustness, are rigorously examined. Furthermore, we delineate promising future prospects centered on cutting-edge genetic engineering, integrated biorefinery concepts, and synergistic coupling with waste treatment to maximize sustainability. By effectively bridging carbon neutrality with renewable resource production, microalgae-based technologies hold considerable potential to spearhead the circular bioeconomy, accelerate the renewable energy transition, and contribute significantly to achieving global climate objectives. Full article

(This article belongs to the Special Issue Algae—The Medium of Bioenergy Conversion: 2nd Edition)

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15 pages, 2645 KiB

Open AccessArticle

Bioconversion of a Glycerol- and Methanol-Rich Residue from Biodiesel Industry into 1,3-Propanediol: The Role of Magnesium

by Rafael de Moraes Altafini, Giovana Masson Fachin and Valeria Reginatto

Fermentation 2025, 11(7), 370; https://doi.org/10.3390/fermentation11070370 - 26 Jun 2025

Viewed by 259

Abstract

Biodiesel is one of the most important biofuels worldwide. Besides glycerol, the residual aqueous phase of the transesterification reaction (RAPTR) from the biodiesel industry contains a high concentration of methanol. Here, we propose using RAPTR as substrate for Clostridium beijerinckii Br21 to produce [...] Read more.

Biodiesel is one of the most important biofuels worldwide. Besides glycerol, the residual aqueous phase of the transesterification reaction (RAPTR) from the biodiesel industry contains a high concentration of methanol. Here, we propose using RAPTR as substrate for Clostridium beijerinckii Br21 to produce 1,3-propanediol (1,3-PDO). 1,3-PDO is a valuable chemical compound widely used in the production of polymers, cosmetics, and pharmaceuticals. To diminish the methanol content, we pretreated RAPTR by low-pressure evaporation, which minimized water evaporation and prevented other contaminants from being concentrated. We optimized the evaporation conditions by using a 2² central composite rotational design to establish optimal temperature and time of 55 °C and 51.3 min, respectively. Pretreated RAPTR diluted at 20% (v v⁻¹) with a nutrient solution allowed the bacterium to grow, but no glycerol was consumed. Supplementing the nutrient solution with 0.4 g L⁻¹ MgCl₂, defined in another experimental design, led the bacterium to consume glycerol and to produce 1,3-PDO. In the optimized conditions, pretreated RAPTR supplemented with MgCl₂ gave 2.78 ± 0.01 g L⁻¹ 1,3-PDO in higher yield (Y_{1,3-PDO/glycerol}) compared to the theoretical one, 0.61 and 0.50 g g⁻¹, respectively. This result is relevant for biodiesel biorefineries, which could implement the innovative and customized strategy proposed herein to obtain 1,3-PDO, a high-value-added product, from a glycerol- and methanol-rich residue. Full article

(This article belongs to the Special Issue Valorisation of Agro-Industrial By-Products Through Fermentation or Eco-Friendly Techniques)

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11 pages, 659 KiB

Open AccessArticle

Orchards and Varietals Shape Apple and Cider Local Microbial Terroirs in the Hudson Valley of New York

by Gabriel G. Perron, Lee C. Miller, Pearson Lau, Lizbeth Davila-Santiago and Swapan S. Jain

Fermentation 2025, 11(7), 369; https://doi.org/10.3390/fermentation11070369 - 26 Jun 2025

Viewed by 275

Abstract

The unique microbial communities present on fruit surfaces significantly influence the fermentation process and product quality of artisanal cider production, constituting a microbial terroir analogous to that recognized in viticulture. In this study, we investigated the microbial composition and diversity associated with the [...] Read more.

The unique microbial communities present on fruit surfaces significantly influence the fermentation process and product quality of artisanal cider production, constituting a microbial terroir analogous to that recognized in viticulture. In this study, we investigated the microbial composition and diversity associated with the apple varietals (Empire, Golden Delicious, and Idared) cultivated by two different orchard producers in the Hudson River Valley of New York. Using 16S rRNA and ITS amplicon sequencing, we identified distinct bacterial and fungal communities that varied significantly according to the apple varietal and orchard location. Notably, the orchard was the dominant factor shaping both the bacterial and fungal communities on the apples’ surfaces, with the varietal differences also playing a significant, albeit secondary, role. For example, we found that the bacterial genera Acidophilim sp. and 1174-901-12 sp., as well as the fungus Sporobolmyces patagonicus, were important markers of the orchard in which the apples were cultivated. These microbial signatures persisted into the early stages of cider fermentation, suggesting their potential influence on the cider quality and flavor profile. Our findings underscore the critical importance of the microbial terroir in cider production, and suggest that targeted management practices can leverage regional microbial diversity to enhance the distinctiveness and marketability of artisanal cider products. Full article

(This article belongs to the Special Issue Advances in Fermented Fruits and Vegetables)

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14 pages, 1182 KiB

Open AccessArticle

Formulation of a Functional Probiotic Beverage Using Maesil (Prunus mume) Syrup By-Product Fermented by Lactiplantibacillus plantarum KFOM 0042

by Chan-Il Bae, Yoon-Soo Gwak, Dasol Nam, Tae Gyu Nam, Hyun-Seok Kim and Mi-Ju Kim

Fermentation 2025, 11(7), 368; https://doi.org/10.3390/fermentation11070368 - 26 Jun 2025

Viewed by 334

Abstract

Maesil (Prunus mume) syrup is the most common form of maesil consumption in Korea; however, its production generates large quantities of by-products. This study aimed to develop a functional probiotic beverage through the lactic acid fermentation of maesil syrup by-products (MSBs). [...] Read more.

Maesil (Prunus mume) syrup is the most common form of maesil consumption in Korea; however, its production generates large quantities of by-products. This study aimed to develop a functional probiotic beverage through the lactic acid fermentation of maesil syrup by-products (MSBs). To optimize fermentation, eight strains of Lactiplantibacillus plantarum were tested, and KFOM 0042 was selected based on its superior acid production in MSBs. The effects of MSB concentration (5%, 10%, 15%, or 20%), pH levels (3, 4, or 5), and sugar type (none, glucose, fructose, or sucrose) were evaluated. The optimal conditions were found to be 20% MSB at pH 4 or 5, either without added sugar or with sucrose. After fermenting under these conditions for 4 days, the probiotic beverages were stored at 4 °C for 30 days to assess stability. All formulations maintained LAB counts above 7 log CFU/mL for 18 days, but only the beverage with sucrose sustained these levels for 25 days. Additionally, antioxidant activity, total polyphenol, and flavonoid content increased post-fermentation, with the highest lactic acid levels observed at pH 5. Overall, this study presents a novel strategy for upcycling MSB into a probiotic beverage with enhanced functional and microbial stability. Full article

(This article belongs to the Special Issue Exploring Fermentation Strategies for the Valorization of Food By-Products and Their Bioactive Potential)

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16 pages, 1733 KiB

Open AccessArticle

Comprehensive Analysis of Formation Water Microorganisms for Their Biosurfactant Potential in MEOR Applications

by Gulzhan Kaiyrmanova, Ulzhan Shaimerdenova, Alisher Assylbek, Almira Amirgaliyeva, Arailym Yerzhan and Aliya Yernazarova

Fermentation 2025, 11(7), 367; https://doi.org/10.3390/fermentation11070367 - 26 Jun 2025

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Abstract

The study is devoted to the analysis of the physicochemical parameters of formation waters, the metagenomic composition of the microbial community and the characteristics of bacterial isolates from the oil fields of Western Kazakhstan to assess their potential in microbial-enhanced oil recovery (MEOR) [...] Read more.

The study is devoted to the analysis of the physicochemical parameters of formation waters, the metagenomic composition of the microbial community and the characteristics of bacterial isolates from the oil fields of Western Kazakhstan to assess their potential in microbial-enhanced oil recovery (MEOR) technologies. Analyses revealed an adaptation of local microorganisms to extreme conditions of high salinity, temperature and pressure, with the dominant presence of Proteobacteria, including the genus Marinobacter. Screening isolates for biosurfactant synthesis showed a high activity of strains M22-7, M93-8C and M142-2, capable of reducing surface tension to 28.81 ± 0.6 mN/m and forming emulsions. Genetic analysis confirmed the presence of key genes (srfAA, srfp) responsible for surfactin synthesis, but the absence of lchAA and rhlAA indicates that the synthesis of other types of biosurfactants is limited. The results highlight the promise of developing microbial consortia and using biosurfactants in high-salinity environments to enhance oil recovery. Full article

(This article belongs to the Section Industrial Fermentation)

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17 pages, 1011 KiB

Open AccessArticle

Bioprocessing of Spent Coffee Grounds as a Sustainable Alternative for the Production of Bioactive Compounds

by Karla A. Luna, Cristóbal N. Aguilar, Nathiely Ramírez-Guzmán, Héctor A. Ruiz, José Luis Martínez and Mónica L. Chávez-González

Fermentation 2025, 11(7), 366; https://doi.org/10.3390/fermentation11070366 - 26 Jun 2025

Viewed by 329

Abstract

Spent coffee grounds are the most abundant waste generated during the preparation of coffee beverages, amounting to 60 million tons per year worldwide. Excessive food waste production has become a global issue, emphasizing the need for waste valorization through the bioprocess of solid-state [...] Read more.

Spent coffee grounds are the most abundant waste generated during the preparation of coffee beverages, amounting to 60 million tons per year worldwide. Excessive food waste production has become a global issue, emphasizing the need for waste valorization through the bioprocess of solid-state fermentation (SSF) for high added-value compounds. This work aims to identify the operational conditions for optimizing the solid-state fermentation process of spent coffee grounds to recover bioactive compounds (as polyphenols). An SSF process was performed using two filamentous fungi (Trichoderma harzianum and Rhizopus oryzae). An exploratory design based on the Hunter & Hunter method was applied to analyze the effects of key parameters such as inoculum size (spores/mL), humidity (%), and temperature (°C). Subsequently, a Box–Behnken experimental design was carried out to recovery of total polyphenols. DPPH, ABTS, and FRAP assays evaluated antioxidant activity. The maximum concentration of polyphenols was observed in treatment T3 (0.279 ± 0.002 TPC mg/g SCG) using T. harzianum, and a similar result was obtained with R. oryzae in the same treatment (0.250 ± 0.011 TPC mg/g SCG). In the Box–Behnken design, the most efficient treatment for T. harzianum was T12 (0.511 ± 0.017 TPC mg/g SCG), and for R. oryzae, T9 (0.636 ± 0.003 TPC mg/g SCG). These extracts could have applications in the food industry to improve preservation and functionality. Full article

(This article belongs to the Special Issue Valorization of Food Waste Using Solid-State Fermentation Technology)

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17 pages, 2384 KiB

Open AccessArticle

Gene Cloning, Purification, and Characterization of a Cold-Active Alkaline Lipase from Bacillus cereus U2

by Baoxiang He, Ning Li, Yan Qin, Liang Xian, Jin Zhou, Sijia Liu, Jing Zhang, Jingtao Wu, Qingyan Wang and Xinquan Liang

Fermentation 2025, 11(7), 365; https://doi.org/10.3390/fermentation11070365 - 25 Jun 2025

Viewed by 373

Abstract

Lipases are important industrial enzymes with a wide range of applications across various sectors. Cold-active lipases are particularly well suited for industrial processes that operate at low temperatures (such as food processing and environmental remediation) due to their high catalytic efficiency and energy-saving [...] Read more.

Lipases are important industrial enzymes with a wide range of applications across various sectors. Cold-active lipases are particularly well suited for industrial processes that operate at low temperatures (such as food processing and environmental remediation) due to their high catalytic efficiency and energy-saving benefits. In this study, a novel lipase—LipU (GenBank accession: PV094892)—was heterologously expressed from Bacillus cereus U2 and characterized for its low-temperature adaptability and alkaline resistance. LipU belongs to the lipase Subfamily I.5 and shares the highest amino acid sequence identity (53.32%) with known homologs. Enzymatic assays revealed that LipU exhibits optimal activity at 20 °C and pH 11. It retained 95% of its initial activity after 24 h of incubation at 4 °C and pH 11.0. Furthermore, the activity of LipU was enhanced by Ca²⁺, Na⁺, Tween 20, and Tween 80, whereas it was inhibited by Cu²⁺, Zn²⁺, Mn²⁺, and sodium dodecyl sulfate (SDS). LipU demonstrated tolerance to various organic solvents of differing polarity; after 1 h of exposure to 15% (v/v) ethanol, n-butanol, isoamyl alcohol, dimethyl sulfoxide, or glycerol, it retained over 78.6% of its activity. These properties make LipU a promising candidate for industrial applications, including for leather degreasing, alkaline wastewater treatment, and low-temperature biocatalysis. Full article

(This article belongs to the Special Issue Fermentation: 10th Anniversary)

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24 pages, 1882 KiB

Open AccessReview

Plant-Based Fermented Foods: Classification, Biochemical Transformations, and Health Benefits

by Beini Peng, Penghui Nie and Hengyi Xu

Fermentation 2025, 11(7), 364; https://doi.org/10.3390/fermentation11070364 - 24 Jun 2025

Viewed by 579

Abstract

In recent years, plant-based fermented foods (PBFs) have become popular all over the world due to their high nutritional value. Compared with traditional foods, PBFs can effectively address dietary issues of high fat content, excessive calories, and elevated cholesterol levels in food formulations, [...] Read more.

In recent years, plant-based fermented foods (PBFs) have become popular all over the world due to their high nutritional value. Compared with traditional foods, PBFs can effectively address dietary issues of high fat content, excessive calories, and elevated cholesterol levels in food formulations, while providing higher nutritional value and enhanced sensory properties (taste and flavor) than conventional plant-based products. These characteristics make PBFs more suitable for people’s yearning for a healthy diet. This review discussed the close relationship between PBFs and human health, elaborating on the definition of PBFs, common types, and the beneficial effects that occur during the fermentation process for human health. Furthermore, we also explored the nutritional value of PBFs. Herein, PBFs are not only rich in probiotics, organic acids, and various bioactive substances that promote gut health and boost immunity but also play a positive role in preventing certain chronic diseases. Finally, this article looks forward to the future development trends of PBFs, predicting their significant potential in healthy eating and sustainability. Full article

(This article belongs to the Section Fermentation for Food and Beverages)

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Fermentation, Volume 11, Issue 7 (July 2025) – 36 articles

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