Fermentation Broth Research Articles

Isolation, Identification, Phytochemical Characterization, and In Vitro Anti-Inflammatory Property of an Endophytic Trametes Versicolor CL-1 Isolated from Rosa Roxburghii.

This study explores the anti-inflammatory potential of an endophytic fungus, Trametes versicolor CL-1, isolated from the fruit tissues of Rosa roxburghii. Morphological and molecular analyses confirmed the identity of CL-1. An ethyl acetate extract (CL-E) from its fermentation broth was subjected to UPLC-HRMS and GNPS molecular networking. The analysis revealed a diverse array of secondary metabolites, including 11 terpenes, 7 flavonoids, 10 cinnamic acid derivatives, 6 oligopeptides, and 9 fatty acids, as verified by LC-MS/MS. Notably, CL-E exhibited significant in vitro anti-inflammatory activity in RAW264.7 cells. Furthermore, molecular docking studies predicted favorable binding interactions of key compounds 1 within CL-E with the NLRP3 inflammasome (PDB ID: 6NPY). These findings suggest T. versicolor CL-1 as a promising source of natural anti-inflammatory agents and unveil R. roxburghii as a potential reservoir for discovering novel bioactive metabolites.

Biocontrol of plant pathogens by Lysobacter enzymogenes isolate LEC: efficacy of shake flask broth, fermentation broth and dried preparations

ABSTRACT The aim of our study was to upscale the production of Lysobacter enzymogenes strain LEC from shake flasks to a laboratory bioreactor. The obtained fermentation broth was to be downstream-processed by lyophilisation and fluidised bed-drying, followed by testing of the dried preparations against plant pathogens. Different batches of broth from shake flasks and from individual fermenter runs were characterised and compared. Number of viable cells, in vitro efficacy (ED90 value) against the apple scab pathogen Ventura inaequalis, as well as efficacy against Phytophthora infestans on potato plants were all reproducible and not impaired by upscaling the production volume from shake flask to the bioreactor. Fermentation broth was processed by lyophilisation and fluidised bed-drying. In bioassays, the activity against downy mildew (Pseudoperonospora cubensis) on cucumber were comparable for the unformulated fermentation broth and the fluidised bed-dried product, while the lyophilised product was significantly more effective. Strain LEC showed reproducible pathogen suppressive activity, independent from production scale and batch. Production upscaling and formulation by drying are possible without loss of efficacy.

A Comprehensive Review on the Total Synthesis of Antibacterial Furanomycin and Its Analogs

l-(+)-Furanomycin 1 is a miniature antibacterial natural product that contains an α-amino acid core. This non-proteinogenic α-amino acid was first isolated in 1967 by Katagiri and co-workers from the fermentation broth of Streptomyces threomyceticus L-803 (ATCC 15795). It is a substrate of isoleucyl aminoacyl-tRNA synthetase that replaces isoleucine in the protein translation process and exhibits antibacterial properties in vitro. It effectively acts as an antibacterial agent against M. tuberculosis, E. coli, B. subtilis, and some Shigella and Salmonella bacterial species at concentrations as low as the micromolar range. Consequently, synthetic chemists have garnered considerable interest from their specific structure–activity profile, distinctive chemical compositions, and distinct biological profile. This review comprehensively describes cutting-edge synthetic methodologies for synthesizing furanomycin and its analogs reported to date. Therefore, this review will offer an initial perspective on synthesizing furanomycin and its customized compounds.

Production and characterization of novel/chimeric sophorose–rhamnose biosurfactants by introducing heterologous rhamnosyltransferase genes into Starmerella bombicola

Glycolipid biosurfactant, sophorolipids (SLs) and rhamnolipids (RLs) can be widely used in agriculture, food and chemical industries. The different physicochemical properties of SLs and RLs, such as hydrophilic lipophilic value (HLB) and critical micelle concentration (CMC), determine they have different application focus. Researchers are still hoping to obtain new glycolipid surfactants with unique surface activities. In this study, we successfully transformed two rhamnosyltransferase genes rhlA and rhlB from Pseudomonas aeruginosa to the sophorolipid-producing Starmerella bombicola CGMGG 1576 to obtain a recombinant strain was SbrhlAB. Two novel components with molecular weight of 554 (C26H50O12) and 536 (C26H48O11) were identified with the ASB C18 column from the fermentation broth of SbrhlAB, the former was a non-acetylated acidic C14:0 glycolipid containing one glucose and one rhamnose, and the latter was an acidic C14:1 glycolipid containing two rhamnoses. With the Venusil MP C18 column, one new glycolipid component was identified as an acidic C18:3 glycolipid with one rhamnose (C24H40O7), which has not been reported before. Our present study demonstrated that novel glycolipids can be synthesized in vivo by reasonable genetic engineering. The results will be helpful to engineer sophorolipid-producing yeast to produce some specific SLs or their derivatives in more rational and controllable way.

Sustainable Biological Production and Innovative Purification of the 1,3-Propanediol from Glycerol Fermentation Broth via Resin Adsorption

The study focuses on enhancing the production and purification of 1,3-Propanediol (1,3-PDO), a versatile compound used across various industries. Conventionally, 1,3-propanediol (1,3-PDO) has been derived from petroleum-based feedstocks through chemical processes, which pose significant cost and environmental concerns. This has prompted the exploration of sustainable biological production methods using microorganisms to ferment glycerol, the main by-product of palm oil transesterification in biodiesel production. However, downstream purification remains complex and inefficient. To address this, our study introduces a novel and economically viable purification strategy for 1,3-PDO derived from a semi-industrial fermentation broth. The purification process involves pre-treatment steps: centrifugation, flocculation with chitosan, decolorization with activated charcoal, and broth concentration via rotary evaporation. These steps resulted in a transparent broth with a minimal 6% loss of 1,3-PDO. Various resin types, including Sulfonated Styrene Divinylbenzene (S-SDVB) and Styrene Divinylbenzene (SDVB) ion exchange resins in different ionic forms in addition to silica gel resin, were evaluated for their effectiveness in separating 1,3-PDO in terms of recovery and purity. A key aspect of our study is the detailed investigation of the equilibrium adsorption characteristics of SDVB and S-SDVB resins, each with different ion forms. This analysis provides insights into how resin modifications affect the separation process, aiming for higher yields and purities of 1,3-PDO. The findings revealed that the Langmuir adsorption isotherm fits experimental data. Column chromatography experiments showed SDVB resins' deficiencies in separating 1,3-PDO from other components, while silica gel resin achieved a recovery rate exceeding 96% purity and approximately 80% overall recovery. Notably, the Ca2+ form of S-SDVB resin achieved high recovery (95-100%) and purity (91-93%) in both synthetic and real fermentation broths, addressing biodiesel challenges and proposing a solution for large-scale microbial 1,3-PDO production.

Combining fermentation broth with spent water recycling for microalgae cultivation: nutrient reutilization, biodiesel production and techno-economic simulation

This study presents an innovative and promising technology, Water Cycling Combined Fermentation Broth (WC2FB), which offers a sustainable solution to significantly reduce the costs associated with microalgae-based biodiesel production. The innovative approach involves utilising food waste as a nutrient source, supplemented by recycled water after microalgae harvesting, with the goal of improving the viability of industrial biofuel production. The results of nutrient removal efficiency demonstrated that the addition of 15% fermentation broth to the microalgal suspension efficiently utilised volatile fatty acids, resulting in a significant increase in lipid content. Additionally, biocomponent analysis confirmed that the WC2FB mode did not compromise the desirable properties of biodiesel. Through techno-economic simulations, we predicted a 90% probability of achieving net present value (NPV) at a selling price of $5/kg. Finally, we recommended that directing future efforts be directly towards the development of culture devices, low-cost bioflocculation methods, and biorefinery extraction to further advance biodiesel production.

Solid-liquid phase microextractive adsorption of bio-lactic acid by a novel microextractor immobilizing ionic liquid A336

The separation of biochemicals poses significant challenges, such as complex product composition, strong hydrophilicity, and high boiling point, which leads to laborious procedures, low yield, and high energy consumption. These obstacles have become bottlenecks for the industrialization of biochemicals. To enhance the efficient separation of bio-lactic acid, a novel microextractor, PS-A336, was synthesized through the copolymerization of ionic liquid (IL) A336 onto a polystyrene (PS) skeleton and further employed to investigate the solid–liquid phase microextractive adsorption (SLPMA). Extensive analysis of PS-A336 microstructure and chemical composition demonstrated its exceptional performance with a rapid (< 20 min) adsorption capacity (1150 mg/g) for LA in the batch system, which is the highest value reported and 11.0 times higher than that of the pristine supports. PS-A336 maintained its stability even after 15 cycles of column chromatography. Its adsorption behavior also fits the common thermodynamic and kinetic models, and it is better for the SLPMA kinetic model established on Fick diffusion law. Additionally, PS-A336 exhibited high adsorption capacity and selectivity for LA from the fermentation broth, achieving above 98 % removal ratios to proteins, inorganic salts, and pigments. The double hydrogen bonds between PS-A336 and LA were identified as the primary driving forces for SLPMA following theoretical and structural investigations. Notably, the immobilized IL in PS-A336 exhibited a remarkable microextraction effect, i.e., an increase in extractive capacity at least 16.6 times due to 59.8-fold improvement in the interface area compared with the bulk IL, which is 28.6 times higher than the adsorption capacity of PS skeleton. Our findings provided new insights into the combination of extraction and adsorption, as well as valuable guidance for the efficient separation of bio-based chemicals.

Genomic characterization and probiotic potency of Bacillus velezensis CPA1-1 reveals its potential for aquaculture applications

Biological prevention and control are increasingly applied in sustainable aquaculture, and Bacillus spp. has been revealed to good alternatives to antibiotics. This research examined the probiotic capabilities of Bacillus velezensis CPA1-1 by genomic and phenotypic analysis. The genome sequence showed that B. velezensis CPA1-1 has a 3,925,520 bp chromosome with 46.49 % GC content and 3762 CDSs. And eight clusters of secondary metabolite biosynthesis genes related to antibacterial compounds were predicted in CPA1-1 genome, including surfactin, difficidin, bacillibactin, fengycin, bacilysin, bacillaene, macrolactin H, butirosin A. Besides, the antimicrobial assay indicated that strain CPA1-1 exhibited strong antagonistic capacity against non-O1/O139 Vibrio cholerae GXFL1-4 isolated from diseased Macrobrachium rosenbergii, and MIC of CPA1-1 fermentation broth against GXFL1-4 was 1.0 × 105 CFU/mL. Furthermore, administering CPA1-1 markedly elevated the activities of ACP, AKP, and SOD in M. rosenbergii, and the immune-related genes, including ALF, Crustin, Hemocyanin, Prophenoloxidase, C-type lectin and HSP70, also exhibited higher expression in the CPA1-1 treated groups. Additionally, M. rosenbergii in the test group treated with CPA1-1 could resist non-O1/O139 V. cholerae GXFL1-4 infection by the challenge test. Our study contributed to reveal biocontrol mechanisms of B. velezensis CPA1-1, and demonstrated that CPA1-1 has promise as a probiotic agent for aquaculture.

Modeling and optimization of adsorption behavior of lactic acid onto zirconium-based metal-organic framework: response surface methodology (RSM)

ABSTRACT Lactic acid is readily generated in bacterial fermentations; however, a significant amount of processing and expenses are required for the purification of lactic acid in the fermentation broth. In this work, the sorption of lactic acid from a simulated broth has been studied by utilizing zirconium-based metal-organic framework (Zr-UiO-66 MOF) that acts as a prominent adsorbent due to its specific geometries and functional groups. The morphological, and structural properties of the prepared MOF are investigated using different characterization techniques such as Field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) analysis, and Brunauer-Emmett-Teller (BET) analysis. The characterization results demonstrate the accuracy of the synthesis procedure. In order to achieve an efficient lactic acid separation process, it is essential to determine the optimal operational conditions. To address this, response surface methodology (RSM) was employed to devise an approach for optimizing five crucial process parameters for achieving the optimal response in lactic acid recovery removal. These parameters include initial LA concentration (ranging from 1 to 36 mg.L−1), pH (3–10), temperature (25 to 55 °C), adsorbent mass (0.25 to 1 g), and contact time (10 to 240 min). The RSM analysis revealed that the quadratic model provided the best fit for the experimental data, with a high coefficient of determination (R2). Three validation trials were carried out to determine the precision of the optimization process, leading to a maximum adsorption efficiency of 97.7% being reached under the optimized conditions (initial concentration = 18.5 mg.L−1, pH = 6.5, adsorbent mass = 0.625 g, contact time = 240 min, and temperature = 40 °C).

The herbicidal activity and mechanism of Talaromyces purpureogenus CY-1 metabolites.

Studies have shown that Talaromyces can produce a large number of secondary metabolites in its metabolic process, many of which have good insecticidal, antibacterial, antitumor, antiviral and other biological activities. In order to explore the herbicidal activity and mechanism of Talaromyces purpureogenus CY-1, we determined the inhibitory effect of the fermentation broth of the CY-1 strain on weeds, identified the major active components, and further investigated the herbicidal mechanism. The results showed that CY-1, with IC50 values of 5.40 g/L and 4.39 g/L, respectively, exhibited good herbicidal activity against Xanthium sibiricum and Amaranthus lividus. Spraying CY-1 strain fermentation broth on redroot pigweed resulted in plant protection efficiencies and fresh weight protection efficiencies of 83.7% and 87%, respectively. The active component identified in the broth was 2-(3-hydroxybenzoyloxy) acrylic acid. Treatment of Amaranthus lividus with 2-(3-hydroxybenzoyloxy) acrylic acid resulted in trends of increasing superoxide dismutase activity, peroxidase activity, respiratory rate, cytochrome oxidase activity, and soluble protein content, followed by a decrease. Peroxidase activity, relative conductance and malondialdehyde content gradually increased, while acetyl lactate synthase and glutamine synthetase initially decreased and gradually returned to normal. The soluble sugar content showed a gradual decrease. The findings of the present study indicate that 2-(3-hydroxybenzoyloxy) acrylic acid can induce oxidative stress in plants, damaging plant cell walls, weakening respiratory activity, inhibiting protein synthesis and sugar metabolism, ultimately leading to weed wilting and death. © 2024 Society of Chemical Industry.

Sweet sorghum as alternative carbon sources for Chlorella sp. valued-added compounds production: A mechanistic insight using transcriptomics

Substituting agricultural by-products for glucose as a carbon source is an effective strategy for reducing the cultivation cost of Chlorella sp. However, the response mechanism of Chlorella sp. to variations in carbon sources remains unclear, and the potential of microalgal biomass for food development warrants further exploration. This study used hydrolysate of sweet sorghum stem juice (HSJ) for the mixotrophic cultivation of Chlorella sp. And transcriptomic analysis was performed to investigate the physiological and metabolic mechanisms as well as the biosynthesis of value-added compounds (e.g., pigments and proteins) of Chlorella sp. in response to changes in carbon sources. The HSJ + NM group (HSJ supplemented with nitrogen and minerals) significantly increased total chlorophyll, carotenoids, lutein, and protein levels by 18.02 %, 13.34 %, 35.95 %, and 20.36 %, respectively, compared to the control (adjusted BG-11 medium supplemented with 10 g/L glucose). Notably, transcript levels of genes for multiple key enzymes involved in glycolysis/gluconeogenesis, TCA cycle, oxidative phosphorylation pathway, and photosynthesis pathways were significantly up-regulated. The activity of these pathways promoted the pigments and proteins synthesis in Chlorella sp. Encouragingly, the cost of cultivating Chlorella sp. with HSJ + NM (0.495 USD/kg) was 43.35 % of glucose (1.142 USD/kg). Further, by fermenting Chlorella sp. cultures with Saccharomyces cerevisiae and further homogenizing and blending the fermentation broth, we developed a nutritious and palatable Chlorella sp. fermented beverage, addressing the common issue of algal odor in such products. This study provides theoretical and practical foundations for the mixotrophic cultivation of microalgae and the application of microalgal biomass in food innovation.

A respiratory Streptococcus strain inhibits Acinetobacter baumannii from causing inflammatory damage through ferroptosis

BackgroundMicroecological equilibrium is essential for human health. Previous research has demonstrated that Streptococcus strain A, the main bacterial group in the respiratory tract, can suppress harmful microbes and protect the body. In this study, Streptococcus strain D19T was isolated from the oral and pharyngeal cavities of healthy children. Its antibacterial mechanism against Acinetobacter baumannii was examined, as well as its potential to prevent inflammatory damage to cells. We evaluated the effect of the fermentation conditions of D19T on inhibition of Acinetobacter baumannii growth; Isolation and purification of antibacterial active components of strain D19T and molecular mechanism of inhibition of Acinetobacter baumannii; Molecular mechanism of D19T antibacterial protein reversing cellular inflammatory injury induced by Acinetobacter baumannii.ResultsThe supernatant of fermentation broth of Streptococcus D19T was the active component against Acinetobacter baumannii, but the bacteria had no antibacterial activity. The supernatant of D19T fermentation broth was precipitated by (NH4)2SO4 solution, and the protein was the active antibacterial component. After gel filtration chromatography and anion gel filtration chromatography, the molecular weight of antibacterial protein was 53kD. D19T antibacterial protein can improve cell membrane permeability, limit extracellular soluble protein release, inhibit Acinetobacter baumannii biofilm formation, and prevent Acinetobacter baumannii adhesion. Acinetobacter baumannii induces inflammatory damage to respiratory cells via ferroptosis, and the D19T antibacterial protein can counteract this damage, protecting the respiratory tract.ConclusionStreptococcus strain D19T, as a potential probiotic, inhibits the growth of Acinetobacter baumannii and the inflammatory damage of respiratory cells, playing a protective role in human respiratory health.

Applicability of blue algae as an activator for microbial enhanced coal bed methane technologies

The blue algae can be used as a nitrogen agent for promoting biological coalbed methane, but its applicability and microbial mechanism in different microbial enhanced coalbed methane technologies kept unknown. This study evaluated the methanogenic efficiency of blue algae addition with a mass ratio of 10% under fermentative degradation and microbial electrolytic cell technologies, and studied the changes of coal microstructure, surface functional groups, organic components and microbiome. The results showed that the algae addition affected the micro-concave-convex structure, non-uniform distribution of micro-particles and micro-cracks of coals, and finally increased the methanogenic rate by 1.74–2.66 times. The algae addition mainly affected the coal organic components including hydroxyl structure, hydrocarbon structure, aliphatic oxygen-containing functional groups and aromatic structure, as well increased the humus acids and microbial metabolites in fermentation broth; among them, the increased metabolites showed great differences between different technologies. The algae addition mainly increased the genera belonging to phylum Bacillota (such as Bacillus and Clostridium) and methanogens (Methanosarcina and Methanoculleus). These Bacillota groups could degrade organic matter into acetate and methanol via pathways of glycolysis and benzoate degradation, which provided substrates for such methanogens. This study strengthened the effectiveness of blue algae in enhancing technologies for biological coalbed methane.

Optimization of Fermentation and Biocontrol Efficacy of Bacillus atrophaeus XHG-1-3m2

Biological control plays an increasingly important role in various aspects of modern agriculture and forestry. Identifying biocontrol strains with commercial potential for effective disease management is currently a focal point in biological control research. In this study, Bacillus atrophaeus XHG-1-3m2, a strain with significant biocontrol potential against Wilsonomyces carpophilus causing shot hole disease in wild apricots, was developed. The study determined the antibacterial activity of the fermentation broth, the optimal fermentation medium composition and conditions, and explored its effectiveness in controlling Wilsonomyces carpophilus. The optimal fermentation medium for strain XHG-1-3m2 comprises 12.5 g/L yeast extract, 12.5 g/L soy peptone, 10.0 g/L sodium chloride, 1 g/L ammonium chloride, 1 g/L potassium dihydrogen phosphate, 1 g/L disodium hydrogen phosphate, and 0.5 g/L magnesium sulfate heptahydrate. With an initial pH of 7.0, a liquid volume of 40%, an inoculum volume of 3%, and shaking incubation at 28 °C for 24 h, the viable cell count reached 14 × 109 CFU/mL. In vitro and in vivo tests on leaves revealed that the fermentation broth and the biocontrol biofertilizer derived from this strain inhibited the leaf lesions caused by Wilsonomyces carpophilus on wild apricots, achieving inhibition rates of 94.62% and 82.46%, respectively.

Metabolic Engineering of Corynebacterium glutamicum for the Production of the Four-Carbon Platform Chemicals γ-Hydroxybutyrate and γ-Butyrolactone.

γ-Hydroxybutyrate (GHB) is an important C4 platform chemical, serving as a crucial precursor for the synthesis of various bulk chemicals, including γ-butyrolactone (GBL) and 1,4-butanediol (1,4-BDO). In this study, we report the systematic metabolic engineering of Corynebacterium glutamicum for the biological production of GHB from glucose via the introduction of a glutamate-derived pathway. We showed that C. glutamicum is a promising host for producing GHB due to its higher tolerance to GHB as compared to other chassis. By screening key enzymes capable of converting glutamate into GHB and blocking byproduct synthesis pathways, an engineered C. glutamicum strain was developed that achieved a GHB production titer of 30.6 g/L. Comparative transcriptome analysis was subsequently employed to identify previously uncharacterized aldehyde dehydrogenases responsible for succinate accumulation, and knockout of the corresponding genes led to an increased GHB titer of 33.7 g/L. Ultimately, the integration of a phosphoketolase-mediated nonoxidative glycolysis (NOG) pathway further enhanced GHB production, resulting in an accumulation of 38.3 g/L of GHB with a yield of 0.615 mol/mol glucose during batch fermentation. The GHB in the fermentation broth can be efficiently converted into GBL by acid treatment with a yield of 0.970 mol/mol.

Efficient conversion from food waste to composite carbon source through rapid fermentation and ceramic membrane filtration

Anaerobic fermentation of food waste (FW) produces a broth rich in small-molecule organic substances, which has the potential as a composite carbon source for denitrification in wastewater treatment. In this study, the idea was tested by optimizing the fermentation process at different hydraulic residence time (HRT), refining fermentation broth through ceramic membrane filtration, and comparing the performance of fermentation filtrate and other commercial carbon sources. A short HRT of 3 days was a suitable fermentation condition with 88% polysaccharide degradation. Acetic acid contributed 40% of soluble chemical oxygen demand in the fermentation broth, followed by ethanol, propanol, lactic acid, and propionic acid, and the five products accounted for 80%. Ceramic membrane filtration can recover more than 70% of dissolved organic matter and more than 60% of small molecular organic matter and simultaneously remove 99% of SS, 41% of total nitrogen, and 62% of total phosphorus. At the rapid degradation stage, the denitrification rates reached 6.68–10.39 mg NOx−-N/(g VSS·h), which was on par with commercial carbon sources. The short fermentation and the rapid membrane separation were integrated to create an efficient treatment system, which provided a feasible pathway to utilize FW combining wastewater treatment.

Isolation and identification of epiphytic Pichia kudriavzevii from loquat peels and investigation of its fermentation characteristics for liquor production.

During the process of fruit wine production, yeast plays a crucial role in influencing the taste, flavor, and overall quality of the wine. This study aims to enhance the flavor and quality of loquat wine by isolating strains of Pichia kudriavzevii (P. kudriavzevii) with desirable winemaking characteristics from loquat fruit fermentation broth. A total of 12 strains of P. kudriavzevii were isolated and subjected to morphological and molecular biological identification. Their fermentation performance, ethanol production, ester production, hydrogen sulfide production, killer activity, and tolerance were evaluated. The results revealed that strains Q-2, Q-9, Q-10, Q-12, Q-20, and Q-42 exhibited robust growth and strong tolerance under conditions of 40°C temperature, 12% ethanol concentration, 350g/L glucose concentration, and pH 2.8. Strain Q-42 demonstrated the strongest gas production capacity, killer activity, and good ester and ethanol production. As a highly active fermentation strain with excellent wine making characteristics, P. kudriavzevii Q-42 provides a valuable yeast resource for the industrial production of loquat wine and offers technical support for improving the overall quality of loquat wine.

Isolation, identification, and technological characteristics analysis of yeast strains from Pyracantha fortuneana fruits fermentation liquid.

Pyracantha fortuneana (P. fortuneana), as a medicinal and edible plant resource, is rich in nutrients. In order to screen the high quality yeast used in Firebone fruit wine, 12 strains of yeast were isolated and purified from P. fortuneana fermentation broth by traditional pure culture method. They were identified by molecular biology as Pichia kudriavzevii (P. kudriavzevii) and Saccharomyces cerevisiae (S. cerevisiae), respectively. Strain HJ-2 could grow normally at 30℃, alcohol content 15%, SO2 mass concentration 360mg/L, pH 3.2, sucrose mass concentration 400g/L and glucose mass concentration 250g/L. Strain HJ-6 could grow normally at 30℃, alcohol content 3%, SO2 concentration 360mg/L, pH 3.2, sucrose concentration 250g/L, glucose concentration 300g/L. Based on the technological characteristics of fruit wine, S. cerevisiae HJ-2 has the potential of brewing P. fortuneana fruit wine. P. kudriavzevii HJ-6 has a low tolerance to ethanol and is suitable for the production of fermented beverages such as low-alcohol wine or beer.

Herbicidal fungal strain isolated from soil in Xinjiang, China.

Weeds pose significant challenges by causing agricultural losses and ecological harm. Over the past decades, many weed species have developed high resistance to chemical herbicides, underscoring the urgent need for new biological herbicide alternatives. In this study, we isolated and screened herbicidal fungi from soil samples in Xinjiang with unique conditions of extreme arid. Notably, we discovered the T. purpureogenus strain Tapu14C02, which shows promising potential as a myco-herbicide. Both its conidia and fermentation broth exhibit broad-spectrum effectiveness against weeds. This research highlights the potential of fungal resources for sustainable agriculture.

Highly efficient synthesis of the chiral ACE inhibitor intermediate (R)-2-hydroxy-4-phenylbutyrate ethyl ester via engineered bi-enzyme coupled systems

(R)-2-Hydroxy-4-phenylbutyric acid ethyl ester ((R)-HPBE) is an essential chiral intermediate in the synthesis of angiotensin-converting enzyme (ACE) inhibitors. Its production involves the highly selective asymmetric reduction of ethyl 2-oxo-4-phenylbutyrate (OPBE), catalyzed by carbonyl reductase (CpCR), with efficient cofactor regeneration playing a crucial role. In this study, an in-situ coenzyme regeneration system was developed by coupling carbonyl reductase (CpCR) with glucose dehydrogenase (GDH), resulting in the construction of five recombinant strains capable of NADPH regeneration. Among these, the recombinant strain E. coli BL21-pETDuet-1-GDH-L-CpCR, where CpCR is fused to the C-terminus of GDH, demonstrated the highest catalytic activity. This strain exhibited an enzyme activity of 69.78 U/mg and achieved a conversion rate of 98.3%, with an enantiomeric excess (ee) of 99.9% during the conversion of 30 mM OPBE to (R)-HPBE. High-density fermentation further enhanced enzyme yield, achieving an enzyme activity of 1960 U/mL in the fermentation broth, which is 16.2 times higher than the volumetric activity obtained from shake flask fermentation. Additionally, the implementation of a substrate feeding strategy enabled continuous processing, allowing the strain to efficiently convert a final OPBE concentration of 920 mM, producing 912 mM of (R)-HPBE. These findings highlight the system’s improved catalytic efficiency, stability, and scalability, making it highly suitable for industrial-scale biocatalytic production.