Search Results (305)

Microbial protein production from acetate represents a promising route for sustainable protein supply, yet its efficiency is constrained by limited understanding of carbon–nitrogen metabolic coordination. In this study, nitrogen availability was systematically varied to investigate its role in regulating biomass composition and protein biosynthesis in Yarrowia lipolytica. Nitrogen limitation markedly reduced cell growth and protein accumulation (19.56% of dry cell weight) while increasing lipid content (up to 34.16%), indicating a altered protein and lipid accumulation under different nitrogen conditions. Transcriptomic analysis revealed a global downregulation of anabolic pathways under nitrogen limitation, accompanied by a shift in nitrogen assimilation from the glutamate dehydrogenase (GDH) pathway to the glutamine synthetase/glutamate synthase (GS–GOGAT) pathway, as well as significant upregulation of genes related to ammonium and amino acid transport. Guided by these findings, metabolic engineering of key nitrogen assimilation pathways was performed. Strains harboring additional copies of GDH and GS expression cassettes showed increased protein content from 48.52% to 55.77% and improved amino acid composition, whereas strains with an additional copy of the GOGAT gene exhibited reduced growth and protein accumulation. These results demonstrate that nitrogen availability regulates biomass composition through coordinated control of nitrogen transport and assimilation, and that balanced upregulation of GDH and GS genes is an effective strategy to improve microbial protein production from acetate, supporting the development of efficient fermentation processes using low-cost carbon sources. Full article

Olive mill wastewater (OMW), due to its high organic load and phenolic content, represents both a major environmental challenge and a promising low-cost substrate for microbial bioprocesses. In this study, lipid production by Yarrowia lipolytica using OMW was optimized through a mixed-level Taguchi experimental design. The effects of OMW dilution (%), nitrogen supplementation, NaCl concentration, sterilization, and carbon source (glucose or glycerol) were evaluated in terms of biomass production, lipid accumulation, and fatty acid composition. The results demonstrated a clear inverse relationship between biomass formation and lipid accumulation. The highest lipid content (33.49%) was achieved under nitrogen-limited conditions combined with a high OMW dilution. After 168 h of fermentation, the calculated lipid yield was 0.51 g/L. Biomass and lipid productivities were calculated as 0.22 g/L/day and 0.073 g/L/day, respectively. ANOVA analysis revealed that nitrogen concentration was the dominant factor affecting lipid production (67.71%), followed by NaCl concentration (18.83%). In contrast, OMW dilution, sterilization, and carbon source type were not statistically significant (p > 0.05), indicating that lipid production can be effectively performed under non-sterile conditions with flexible substrate utilization. Fatty acid analysis revealed that the produced lipids were rich in oleic acid (C18:1n9c), reaching up to 57.97%, with unsaturated fatty acids generally accounting for the majority of the total fatty acid composition. Although the carbon source had a limited effect on lipid yield, it contributed to variations in fatty acid composition, suggesting the possibility of tailoring lipid quality through substrate selection. Full article

Amaranthin is a major red-violet betacyanin of Amaranthaceae and an increasingly relevant natural pigment for food, cosmetic, nutraceutical, and biotechnological applications. This review integrates knowledge from over 100 studies, addressing amaranthin as a chemically defined betalain, distinguishing it from other scientific uses of the term, and evaluates its natural sources, analytical methods, extraction strategies, in vitro production systems, biosynthetic regulation, and biological activity. Cultivated Amaranthus species are among the richest plant sources, with total betacyanins of 46.1–199 mg/100 g fresh weight and amaranthin comprising, on average, 80.9% of the pigment fraction. Reliable identification and quantification rely on high-performance liquid chromatography coupled with a diode array detector (HPLC-DAD), liquid chromatography-tandem mass spectrometry (LC-MS/MS), and ultraviolet–visible (UV–Vis) spectrophotometry. Microwave- and ultrasound-assisted extraction can improve pigment recovery under optimized conditions, although its stability depends strongly on pH, temperature, solvent, time and storage parameters. While plant in vitro cultures, including callus, suspension, and shoot systems, have clarified biosynthetic regulation and offer controlled production platforms, engineered yeast systems have recently expanded production options, with Yarrowia lipolytica reaching 2.97 ± 0.029 g L⁻¹ amaranthin in fed-batch fermentation. Amaranthin-rich extracts and amaranthin-type pigments show antioxidantand anti-inflammatory potential, while antimicrobial and antiviral activities have mainly been reported for mixed betacyanin fractions; direct mechanistic, bioavailability, and in vivo evidence for purified amaranthin remains limited. Standardized analytical protocols, further investigation of stable high-yield sources, physicochemical stability assessment, and structure–activity studies are identified as priorities for advancing future application-oriented research on this multipotential pigment. Full article

This focused review examines fermentation and fermentation-integrated microbial platforms that convert two regionally relevant substrate classes, Latin American agro-industrial residues and concentrated CO₂ streams, into high-value bioproducts. The review is not intended as a complete survey of all biomass valorization routes in Latin America. Instead, it evaluates platform–feedstock–product combinations with clear translational relevance for regional biorefineries, with emphasis on literature from 2020–2025 and on earlier benchmark studies only when they define current technical performance limits. Latin America and the Caribbean combine high-volume sugarcane, agave, coffee, citrus, banana, cacao, and tuber-processing residues with biogenic CO₂ from ethanol fermentation and industrial point sources from cement, lime, and oil-and-gas operations. The technical opportunity is therefore not residue abundance alone, but the rational coupling of residue chemistry, CO₂-source quality, locally isolated microbial strains, and process architectures that can be scaled under regional constraints. We compare phototrophic CO₂-fixing modules based on cyanobacteria and microalgae, chemoautotrophic gas fermentation using Cupriavidus necator and related systems, heterotrophic yeast platforms including Rhodotorula spp. and Yarrowia lipolytica, and bacterial platforms for PHAs, bacterial cellulose, and organic acids. The core technical analysis focuses on substrate conditioning, hydrolysate inhibition, oxygen- and gas-transfer constraints, light delivery, C/N control, mixed-sugar utilization, metabolic engineering, reactor configuration, downstream processing, and quantitative reporting metrics. One fermentation-integrated laboratory case study—the Synechocystis sp. PCC 6803–Rhodotorula mucilaginosa UANL-001L CO₂-to-carotenoid relay—and one explicitly defined non-fermentative boundary case on peel-extract-derived coating films are used to illustrate two different aspects of regional biorefinery design: dual-feedstock microbial conversion and low-CapEx product-fit decisions for agro-industrial residues. We conclude that Latin America’s strongest near-term position is in technically disciplined, product-specific biorefineries that integrate local feedstock chemistry with engineered or locally adapted chassis, rather than in generic biomass-to-product claims. Full article

Poly(ε-caprolactone) (PCL) is a biodegradable aliphatic polyester with applications in many areas. Lipase B from Moesziomyces antarcticus (CALB, previously known as Candida antarctica lipase B) is a well-characterize enzyme capable of hydrolysing several polyesters. In this study, the codon-optimized gene encoding CALB was cloned into the yeast Yarrowia lipolytica to enhance its natural capabilities toward polyesters biodegradation. PCL films biodegradation was conducted directly in the medium using the engineered yeast at 28 °C. Process optimization employing baffled flasks significantly improved degradation efficiency and reduced time to 24 h. This study showed that the engineered yeast Y. lipolytica is a promising host for polyester biodegradation. Full article

Carbonic anhydrases (CAs) efficiently catalyze CO₂ reversible hydration, critical for carbon capture and sequestration (CCS), but naturally low yield limits industrial use. Yarrowia lipolytica, an unconventional yeast, is an ideal heterologous expression host with robust adaptability, post-translational modification capacity, and versatile genetic tools. In this study, 10 α-, β-, and γ-class CAs were successfully expressed in Y. lipolytica, and two top-performing candidates were identified: Methanosarcina mazei γ-CA (MmaCA) and Sulfurihydrogenibium azorense α-CA (SazCA). Their production was further optimized via promoter and gene dosage adjustment, cultural condition optimization and auxiliary protein co-expression. The optimized intracellular MmaCA activity reached 960 U/mL (64.42-fold improvement), and the extracellular SazCA activity peaked at 925 U/mL (70.08-fold enhancement). CO₂ mineralization experiments confirmed both recombinant CAs significantly accelerated CaCO₃ precipitation, demonstrating a promising CCS application potential. To our knowledge, this is the first systematic investigation of CA heterologously expressed in Y. lipolytica, providing a novel strategy for the highly efficient production of CAs to enable their application in industry. Full article

In this study we compared seven wild-type strains of Yarrowia lipolytica as a chassis for aliphatic polyester biodegradation. To this end, we overexpressed the native Lip2 lipase under the strong UASB16-TEF promoter and compared the capability of the engineered strains towards polycaprolactone (PCL) biodegradation. The parental strains are wild types isolated from various sources and geographical regions. Despite the fact that all belong to the Yarrowia lipolytica species, a high diversity among the strains was observed. This study clearly indicates that, for biotechnological applications of the engineered strains, it is crucial to select a proper host for an efficient process. Full article

Plastic pollution is a global environmental crisis, and microbial degradation represents a promising remediation strategy. While bacteria have been widely studied, yeasts offer unique advantages for plastic degradation due to their metabolic versatility, stress tolerance, and enzymatic capabilities. However, plastic degradative yeasts have not been reviewed comprehensively. Although several yeasts capable of degrading polyethylene terephthalate (PET) or polyethylene (PE) have been reported (e.g., Moesziomyces antarcticus, Candida tropicalis, Yarrowia lipolytica and Rhodotorula mucilaginosa), degraders of other plastic types are less studied. Although some yeasts can assimilate carbon from plastics, the diversity of yeasts capable of participating in plastic mineralization remains vastly underexplored. In recent years, yeast cell surface display systems for bacterial PETase and fungal cutinase have been developed, demonstrating promising PET degradation efficiency. However, PETase is feedback-inhibited by the intermediate product mono(2-hydroxyethyl)terephthalate (MHET). Systems synergizing PETase with MHETase have shown superior stability during long-term PET degradation and enable large-scale depolymerization of PET waste. For high-crystallinity PET, fungal hydrophobins can be used to modify the surface hydrophobicity of PETase-displaying yeast cells, facilitating their attachment to hydrophobic PET surfaces and ultimately enhancing the degradation efficiency of the whole-cell biocatalyst. Limitations of current research and future directions are also discussed. Full article

The increasing demand for environmentally sustainable and efficient laundry detergents has prompted the exploration of innovative biotechnological solutions. This study aims to integrate solid fermentation and by-product valorization for high-quality proteases suitable for laundry detergents. Of 486 strains isolated from fruit by-products, 9 were selected for their proteolytic activity, but only 3 showed proteolytic activity in the presence of detergent components. Strain M17, identified as Yarrowia lipolytica (Yl), proved to be the most effective in producing proteolytic extracts with activity similar to that found in commercial detergents. The produced proteases were incorporated into laundry detergent formulations, and their enzyme activity was compared with that of commercial laundry detergents. The results showed that the proteolytic extracts have enzyme activity similar to that of commercial laundry detergents. Culture media were developed to enhance protease production using fruit by-products. The highest activity (43.71 U (g dm)⁻¹) was achieved at C/N = 20.04, while the best productivity (1.37 U (g dm·h)⁻¹) at pH 7.0 and 30 °C was observed. The results demonstrate that culture media based on fruits and vegetable by-products enhance protease yield and activity. This approach not only reduces waste but also adds value to natural resources through an environmentally friendly process. This study underscores the potential of combining solid-state fermentation with by-products. Using Yl in combination with fruit and vegetable by-products is a practical, eco-friendly method for producing high-quality proteases for laundry detergents. This green enzyme innovation offers significant promise for advancing the detergent proteolytic enzymes and promoting sustainable practices in by-product management. Full article

Olive mill wastewater (OMWW) is a highly polluting agro-industrial effluent characterized by elevated organic load, low pH, and high concentrations of phenolic compounds responsible for its phytotoxicity and dark coloration. In this study, 41 non-conventional yeast strains belonging to the University of Basilicata Yeast Collection (UBYC), were tested for both the oleaginous potential traits and OMWW detoxification capacity in comparison to two commercial oleaginous controls, Yarrowia lipolytica ATCC 46483 and Lipomyces tetrasporus Li-0407. Primary screening in synthetic medium under nitrogen-limited conditions revealed widespread intracellular lipid accumulation. Quantitative analysis showed lipid contents above 20% (w/w) in some strains, with Candida tropicalis AII122 (33.3%) and Pichia manshurica ML-3 (29.4%) exhibiting the highest values in synthetic medium. The cultivation of eight selected strains in synthetic medium supplemented with 15% (v/v) of OMWW reduced intracellular lipid accumulation, with the highest value of 6.48% for the 2R1 strain. Levels of phenol reduction and color removal were highly different among all the analyzed strains, and C. tropicalis AII122 achieved the highest phenolic reduction and decolorization ability. These findings demonstrate that indigenous non-conventional yeasts represent a source of natural biodiversity, supporting sustainable waste valorization strategies based on the use of selected microorganisms within a circular bioeconomy framework. Full article

Proteases are key biocatalysts widely applied in the food, pharmaceutical, detergent, and environmental industries. One of the most costly steps in large-scale enzyme production is the preparation of the culture medium, making agro-industrial wastes attractive as low-cost nutrient sources and potential inducers. The non-conventional yeast Yarrowia lipolytica stands out in bioprocess engineering due to its high secretion capacity, GRAS status, and ability to metabolize diverse industrial residues. In this study, Brazilian agro-industrial by-products, namely Corn steep liquor (CSL), brewer’s yeast residue (BYR), and okara, were evaluated as alternative nitrogen sources for protease production by Y. lipolytica IMUFRJ 50678. Enzyme activity was quantified by the azocasein method at optimized conditions (40 °C, 40 min, pH 5 and 8). After an initial exploratory screening (n = 1), brewer’s yeast residue (BYR) and okara were identified as promising candidates for protease production. These preliminary findings guided subsequent experiments performed in biological triplicate (n = 3), which confirmed the reproducibility and comparative performance of these substrates, showing higher acid protease (AXP) activity in the BYR medium ((5.4 ± 0.3) U/mL), whereas alkaline protease (AEP) activities were comparable between the BYR ((8.4 ± 0.6) U/mL) and okara ((7.5 ± 0.9) U/mL) media. CSL was associated with higher lipase activity ((11.7 ± 0.9) × 10³ U/L), while esterase activity was higher in the BYR medium. These findings indicate that agro-industrial residues, particularly BYR and okara, can serve as effective nitrogen sources for protease production by Y. lipolytica IMUFRJ 50678, supporting their use in waste valorization and sustainable bioprocesses. Full article

Microbial oil production has gained attention as a sustainable and cost-effective alternative to conventional vegetable and fish oils. Among oleaginous microorganisms, Yarrowia lipolytica is notable for its ability to accumulate lipids exceeding 20% of its dry weight. This study aimed to evaluate semi-continuous cultivation as a strategy for sustainable microbial oil production by Y. lipolytica, while also assessing the potential utility of the spent supernatant. Three different feeding frequencies were evaluated. In the 24 h feeding regime, the maximum oil concentration reached 11.22 g/L, decreasing to 8.43 g/L by the 88th hour. In the 6–6–12 h feeding strategy, crude protein content peaked at 43.75% of dry mass at 22 h. Fatty acid profiling revealed consistently low saturated fatty acid (SFA) levels (4.93–10.30%), while unsaturated fatty acids (UFA) dominated (89.69–95.05%). Monounsaturated fatty acids (MUFA) were predominant, reaching up to 81.24%, whereas polyunsaturated fatty acids (PUFA) ranged from 20.78% to 29.98%. Oleic acid was the most abundant fatty acid across all conditions. This composition supports the potential of microbial oil from Y. lipolytica as a sustainable alternative edible lipid ingredient for human food applications, complementing conventional plant-based oils. The favorable unsaturated fatty acid profile indicates its potential suitability for incorporation into food formulations requiring nutritionally desirable lipid sources. As part of the sustainability-oriented approach of the study, the freeze-dried post-culture supernatant was also evaluated for its potential further utilization. With a calorific value of 10.43 kJ/g and significant phosphorus and potassium levels, it shows potential as a biofuel feedstock and as a biofertilizer or biostimulant. Full article

Chickpea flour represents a valuable plant-based ingredient due to its high protein and fiber content; however, its application is limited by antinutritional factors and off-flavor compounds. Fermentation with LAB and yeasts, applied individually or in consortia, resulted in significant microbiological, nutritional, and aromatic changes. The fastest acidification (pH 3.9) and the most effective control of Enterobacteriaceae (<4 log CFU/g after 48 h) were observed in samples containing Lactiplantibacillus plantarum LP23, both as a monoculture and in combination with Debaryomyces hansenii Y15A. Peptide content significantly increased in all fermented samples compared to the control, with a synergistic effect in the co-culture Yarrowia lipolytica Y3 + Lacticaseibacillus paracasei L (around 230%). A pronounced reduction in raffinose-family oligosaccharides was observed, especially in the consortia Y. lipolytica Y3 + Lcb. paracasei L and D. hansenii Y15A + Lacp. plantarum LP23 (0.11–0.16 mmol/100 g). Samples with lower total volatile levels showed higher olfactory acceptability due to a marked reduction in aldehydes (up to 70–95% vs. control), and a balanced accumulation of alcohols, esters, ketones, and organic acids. Overall, LAB–yeast consortia effectively enhanced the nutritional quality, safety, and sensory properties of chickpea flour, supporting its use as a functional ingredient in plant-based foods. Full article

Microorganisms are increasingly being used for the industrial production of raw materials for food, chemical products and pharmaceuticals. The unconventional yeast Yarrowia lipolytica has a rising profile as a platform for industrial biotechnology. It has attractive physiological and metabolic properties, including high terpene and lipid production, high tolerance to complex environments, and amenability to genetic modification. Y. lipolytica naturally produces sufficient levels of cytosolic acetyl-CoA and malonyl-CoA to achieve lipid accumulation. Engineering biology methods allow transformation of these native metabolites into synthetic precursors for high-value compounds such as terpenes and flavonoids. Gene-editing, expression, and regulation tools have been developed for Y. lipolytica, facilitating improvement in bio-manufacturing yields for this chassis. This review summarizes natural product yields in Y. lipolytica and strategies for improving productivity. We highlight morphological engineering, metabolic engineering, and adaptive laboratory evolution as key strategies that can be used to improve the future yield, productivity and controllability of target molecules for Y. lipolytica engineering. Full article

Oxidative stress (OS) is generated by the imbalance between reactive oxygen species (ROS) and antioxidant enzyme activities, such as catalases, superoxide dismutases, and glutathione peroxidases. In the Y. lipolytica genome, three genes encoding catalases (CAT1, CAT2, and CAT3) have been identified; all three genes are transcriptionally active in cells grown under OS conditions. This study aimed to analyze whether the CAT1 and CAT2 genes exhibit a compensatory function that allows maintaining the functionality of the antioxidant response in Y. lipolytica cells lacking the CAT3 gene. The construction of the mutant strain (Ylcat3-Δ) was performed using Double-Joint PCR. OS was induced by the addition of H₂O₂ [5 mM], ROS production was quantified by fluorescence using 2′,7′-dichlorofluorescein diacetate (DCFH-DA), and gene expression was analyzed by semi-quantitative RT-PCR in both parental (P01a) and mutant (Ylcat3-Δ) strains exposed or not to oxidative conditions. ROS production was lower in P01a cells than in Ylcat3-Δ cells when exposed to H₂O₂ [5 mM]. Also, under OS conditions, CAT1 gene expression levels decreased in both strains, whereas CAT2 gene expression increased in both types of cells. Under OS, both parental and Ylcat3-Δ strains showed similar growth rate, sensitivity to oxidative conditions and gene expression patterns, and it can be concluded that CAT3 gene deletion does not alter the transcriptional activity of CAT1 and CAT2 genes, suggesting that the compensatory function among the CAT genes of Y. lipolytica may not be limited to the presence/absence of CAT3 gene. Full article