Production Of Biomolecules Research Articles

Microbial Dynamics and Quality Monitoring in Biopharmaceutical Production

AbstractProkaryotic cells are pivotal in meeting the global demand for biopharmaceuticals. However, challenges such as the absence of advanced technology for real‐time monitoring, standardized testing methodologies, and quality risk assessment of microbial activity have led to increased production costs, delays, and shortages of biopharmaceutical products. A thorough understanding of how biomolecule production interacts with microbial population structure and function is vital for improving continuous manufacturing and process automation. In this review, we discuss the current microbiological techniques that meet good manufacturing practice requirements in industrial settings, explore the advantages of monitoring and measuring biomass growth efficiency and turnover rates beyond regulatory criteria for product release, and provide a critical assessment of the current state of knowledge on bioassays and engineering tools for biomolecule yield measurement and monitoring. Furthermore, we identify areas for future development, potential applications, and the need for interdisciplinary innovation to drive future research, including advancing bioassays for biopharmaceutical wastewater risk.

Composition of Sodium Alginate Films Containing Copper Oxide Nanoparticles Synthesized Using Aqueous Extract of Turnera subulata Sm and Evaluation of Their Healing Potential In Vivo

ABSTRACTSodium alginate is used in wound care because of its hydrogel‐forming properties and ability to protect the wound. Copper nanoparticles have properties that inhibit the growth of microorganisms and mediate the production of essential biomolecules for the healing process, making them an excellent choice for constructing nanocomposites for wound treatment. This work aimed to synthesize copper nanoparticles using an aqueous extract of Turnera subulata Sm. and incorporate them into sodium alginate to obtain films with healing potential. The proposed system was characterized by ultraviolet–visible spectroscopy (UV–vis), Fourier‐transform infrared (FTIR), dynamic light scattering (DLS), atomic force microscopy (AFM), x‐ray crystallography, and biocompatibility verified by hemolysis test. The UV–vis analysis showed that CuO NPs absorb at 280 and 404 nm. The FTIR spectra revealed stretching and folding modes of the functional groups present in the aqueous extract of T. subulata responsible for the reduction/stabilization of the copper ion, as well as signals at 780 and 618 cm−1 originating from the CuO bond. Size estimation using DLS revealed 564.5 and 394.2 nm. AFM data showed that adding copper oxide nanoparticles (CuO NPs) changed alginate roughness, and surface imaging revealed a material with a uniform appearance. The hemolysis test showed hemocompatibility of CuO NPs at all tested concentrations. Histology showed that CuONP‐loaded alginate films accelerated the healing process.

Crosstalk between macrophages and mesenchymal stem cells shape patterns of osteogenesis and immunomodulation in mineralized collagen scaffolds

Mesenchymal stem cells (MSCs) are highly plastic, with the capacity to differentiate into a spectrum of tissue-specific stromal cells. In the field of bone regeneration, MSCs have largely been considered for their osteogenic differentiation capacity. MSCs are increasingly being appreciated for their immunomodulatory potential following exposure to pro-inflammatory stimuli (licensing). Pro-inflammatory environments arise following bone injury via activation of resident immune cells like macrophages. We describe the use of a mineralized collagen scaffold as a bone-mimetic in vitro model to study the influence of paracrine versus direct cell-to-cell contact of THP-1 macrophages on MSC osteogenic and immunomodulatory potential. Paracrine stimuli from macrophages enhance MSC osteogenic and immunomodulatory potential via upregulation of key transcriptomic markers as well as via soluble biomolecule production. Direct co-culture of MSCs and macrophages decreased immunomodulatory potential in MSCs, especially for licensed MSCs, but enhanced matrix remodeling and expression of genes related to macrophage chemotaxis. These data demonstrate the significant effect macrophage-derived paracrine factors and direct contact have on MSC activity in a biomaterial model of bone regeneration. This work illuminates a critical need to further understand these processes in more clinically relevant cell models to inform biomaterial design.

Repeated glucose oscillations in high cell-density cultures influence stress-related functions of Escherichia coli.

Engineering microbial cells for the commercial production of biomolecules and biochemicals requires understanding how cells respond to dynamically changing substrate (feast-famine) conditions in industrial-scale bioreactors. Scale-down methods that oscillate substrate are commonly applied to predict the industrial-scale behavior of microbes. We followed a compartment modeling approach to design a scale-down method based on the simulation of an industrial-scale bioreactor. This study uses high cell-density scale-down experiments to investigate Escherichia coli knockout strains of five major glucose-sensitive transcription factors (Cra, Crp, FliA, PrpR, and RpoS) to study their regulatory role during glucose oscillations. RNA-sequencing analysis revealed that the glucose oscillations caused the down-regulation of several stress-related functions in E. coli. An in-depth analysis of strain physiology and transcriptome revealed a distinct phenotype of the strains tested under glucose oscillations. Specifically, the knockout strains of Cra, Crp, and RpoS resulted in a more sensitive transcriptional response than the control strain, while the knockouts of FliA and PrpR responded less severely. These findings imply that the regulation orchestrated by Cra, Crp, and RpoS may be essential for robust E. coli production strains. In contrast, the regulation by FliA and PrpR may be undesirable for temporal oscillations in glucose availability.

An Examination of Chemical Tools for Hydrogen Selenide Donation and Detection.

Hydrogen selenide (H2Se) is an emerging biomolecule of interest with similar properties to that of other gaseous signaling molecules (i.e., gasotransmitters that include nitric oxide, carbon monoxide, and hydrogen sulfide). H2Se is enzymatically generated in humans where it serves as a key metabolic intermediate in the production of selenoproteins and other selenium-containing biomolecules. However, beyond its participation in biosynthetic pathways, its involvement in cellular signaling or other biological mechanisms remains unclear. To uncover its true biological significance, H2Se-specific chemical tools capable of functioning under physiological conditions are required but lacking in comparison to those that exist for other gasotransmitters. Recently, researchers have begun to fill this unmet need by developing new H2Se-releasing compounds, along with pioneering methods for selenide detection and quantification. In combination, the chemical tools highlighted in this review have the potential to spark groundbreaking explorations into the chemical biology of H2Se, which may lead to its branding as the fourth official gasotransmitter.

Fabricated devices for performing bacterial-fungal interaction experiments across scales.

Diverse and complex microbiomes are found in virtually every environment on Earth. Bacteria and fungi often co-dominate environmental microbiomes, and there is growing recognition that bacterial-fungal interactions (BFI) have significant impacts on the functioning of their associated microbiomes, environments, and hosts. Investigating BFI in vitro remains a challenge, particularly when attempting to examine interactions at multiple scales of system complexity. Fabricated devices can provide control over both biotic composition and abiotic factors within an experiment to enable the characterization of diverse BFI phenotypes such as modulation of growth rate, production of biomolecules, and alterations to physical movements. Engineered devices ranging from microfluidic chips to simulated rhizosphere systems have been and will continue to be invaluable to BFI research, and it is anticipated that such devices will continue to be developed for diverse applications in the field. This will allow researchers to address specific questions regarding the nature of BFI and how they impact larger microbiome and environmental processes such as biogeochemical cycles, plant productivity, and overall ecosystem resilience. Devices that are currently used for experimental investigations of bacteria, fungi, and BFI are discussed herein along with some of the associated challenges and several recommendations for future device design and applications.

Strategies for improvement of bioactive compounds production using microalgal consortia: An emerging concept for current and future perspective

In recent times, microalgae have been recognized as one of the most potential sources of biomolecules with therapeutic potential. Microalgae are rich sources of polyunsaturated fatty acids, proteins, carbohydrates, carotenoids, and vitamins. These compounds have significant anticancer, antioxidant, anti-aging, antidiabetic, hepatoprotective, and anti-inflammatory potentials. Until now, monoculture of microalgae has been the most preferred way to produce these compounds. However, this method faces the challenge of low biomass and biomolecule production and a high risk of contamination. Controlled symbiotic co-culture of microalgae with suitable microorganisms can overcome these challenges. Therefore, it is crucial to explore the compatibility of microalgae with other microorganisms to develop novel consortia to enhance biomass and biomolecule production. The article comprehensively reviews the strategies for the improvement of bioactive compound production using microalgal consortia (SIBCP-MC) viz. microalgae, fungi, bacteria, and cyanobacteria. It also discusses the mechanisms of their interaction, economic viability, and a comparison of expected revenue generation from different types of microalgal consortia. The review mainly focuses on the therapeutic potentials of microalgae biomolecules and the optimization of different factors, such as the selection of consortium partners, inoculum ratio, cultivation types and modes, temperature, pH, light intensity, and photoperiod, that affect the biomass and biomolecule production of microalgal consortia which in future helps in enhancement in biomass and biomolecules production from microalgae and curing chronic diseases. The review discusses various types of microalgal consortia, aiding in selecting the most suitable consortia for future use. The review compares their biomass and biomolecule production with monoculture, outlining microalgal consortia's advantages, challenges, and prospects. Additionally, it discusses advanced artificial intelligence techniques that could assist in the future in the selection of compatible organisms and predict expected revenue generation.

Exploring the role of RNASET2 in the immune response of black soldier fly larvae.

T2 RNases are transferase-type enzymes distributed across phyla, crucial for breaking down single-stranded RNA molecules. In addition to their canonical function, several T2 enzymes exhibit pleiotropic roles, contributing to various biological processes, such as the immune response in invertebrates and vertebrates. This study aims at characterizing RNASET2 in the larvae of black soldier fly (BSF), Hermetia illucens, which are used for organic waste reduction and the production of valuable insect biomolecules for feed formulation and other applications. Given the exposure of BSF larvae to pathogens present in the feeding substrate, it is likely that the mechanisms of their immune response have undergone significant evolution and increased complexity. After in silico characterization of HiRNASET2, demonstrating the high conservation of this T2 homolog, we investigated the expression pattern of the enzyme in the fat body and hemocytes, two districts mainly involved in the insect immune response, in larvae challenged with bacterial infection. While no variation in HiRNASET2 expression was observed in the fat body following infection, a significant upregulation of HiRNASET2 synthesis occurred in hemocytes shortly after the injection of bacteria in the larva. The intracellular localization of HiRNASET2 in lysosomes of plasmatocytes, its extracellular association with bacteria, and the presence of a putative antimicrobial domain in the molecule, suggest its potential role in RNA clean-up and as an alarm molecule promoting phagocytosis activation by hemocytes. These insights contribute to the characterization of the immune response ofHermetia illucens larvae and may facilitate the development of animal feedstuff enriched with highly valuable BSF bioactive compounds.

Bioconversion of Alternative Substrates for the Biosynthesis of HMG-CoA Reductase Inhibitors by Aspergillus spp. Strains with Antimicrobial Potential

Simvastatin, a semisynthetic drug widely used to lower cholesterol, is among the most prescribed statins worldwide. This study focuses on the direct production of a simvastatin-like biomolecule using alternative substrates by Aspergillus spp. strains. Two species, A. terreus UCP 1276 and A. flavus UCP 0316, were initially evaluated in synthetic media as control. Subsequently, the carbon and nitrogen sources were replaced by agro-industrial substrates, resulting in five modified media. Cultures were maintained at 28 °C, pH 6.5, at 180 rpm for 21 days. Fungal growth kinetics were evaluated and a 23 full-factorial design (FFD) was used to investigate the influence of substrate concentration on statin yield. Presence of inhibitors was confirmed by bioassay, UV–visible spectrophotometry, and thin-layer chromatography (TLC). According to the results, A. flavus UCP yielded 0.24 mg/g of statin in condition 2 of FFD (medium containing 4.5% soluble starch and saline base), suggesting it as a promising candidate for direct production of the biomolecule. Statistical analysis showed the significant effect of soluble starch on inhibitor production, making it a viable and profitable alternative substrate. Moreover, the isolated statin exhibited broad-spectrum antimicrobial activity, including efficacy against Gram-negative and Gram-positive bacteria and yeasts, indicating therapeutic potential against antimicrobial resistance.

Phycoremediation of As(III) and Cr(VI) by Desmodesmus subspicatus: Impact on growth and biomolecules (carbohydrate, protein, chlorophyll and lipid) - A dual mode investigation.

Microalgae are under research focus for the simultaneous production of biomolecules (e.g., carbohydrates, proteins, pigments and lipids) and bioremediation of toxic substances from wastewater. The current study explores the capability of indigenously isolated microalgae (Desmodesmus subspicatus) for the phycoremediation of As(III) and Cr(VI). Variation of biomolecules (carbohydrate, protein, lipid and chlorophyll) was investigated during phycoremediation. D. subspicatus survived up to the toxicity level of 10mg/L for As(III) and 0.8mg/L for Cr(VI). A 70% decline in carbohydrate accumulation was observed at 10mg/L of As(III). An increased content of proteins (+ 28%) and lipids (+ 32%) within the cells was observed while growing in 0.5 and 0.2mg/L of As(III) and Cr(VI) respectively. A decrease in carbohydrate accumulation was noted with increasing Cr(VI) concentration, and the lowest (- 44%) was recorded at 0.8mg/L Cr(VI). D. subspicatus showed an excellent maximum removal efficiency for Cr(VI) and As(III) as 77% and 90% respectively.

Vibrational imaging of metabolites for improved microbial cell strains.

Biomanufacturing utilizes modified microbial systems to sustainably produce commercially important biomolecules for use in agricultural, energy, food, material, and pharmaceutical industries. However, technological challenges related to non-destructive and high-throughput metabolite screening need to be addressed to fully unlock the potential of synthetic biology and sustainable biomanufacturing. This perspective outlines current analytical screening tools used in industrial cell strain development programs and introduces label-free vibrational spectro-microscopy as an alternative contrast mechanism. We provide an overview of the analytical instrumentation currently used in the "test" portion of the design, build, test, and learn cycle of synthetic biology. We then highlight recent progress in Raman scattering and infrared absorption imaging techniques, which have enabled improved molecular specificity and sensitivity. Recent developments in high-resolution chemical imaging methods allow for greater throughput without compromising the image contrast. We provide a roadmap of future work needed to support integration with microfluidics for rapid screening at the single-cell level. Quantifying the net expression of metabolites allows for the identification of cells with metabolic pathways that result in increased biomolecule production, which is essential for improving the yield and reducing the cost of industrial biomanufacturing. Technological advancements in vibrational microscopy instrumentation will greatly benefit biofoundries as a complementary approach for non-destructive cell screening.

Surfactant-assisted thermal hydrolysis of sewage sludge: Biomolecule extraction and its potential for protease production

Efficient management of sewage sludge from wastewater treatment plants (WWTPs) are crucial to obtain industrial value-added products and reducing environmental impact. Thermal hydrolysis, coupled with surfactants to enhance solubilisation, offers a promising approach for sewage sludge treatment. This study assessed the impact of four surfactants: sodium dodecyl sulphate (SDS), sodium dodecylbenzenesulfonate (SDBS), cetyl trimethyl ammonium chloride (CTAC), and tetraethylammonium chloride (TAC) on thermal hydrolysis of sewage sludge. The addition of anionic surfactants (SDS and SDBS) significantly increased biomolecule production, with proteins, humic-like substances, carbohydrates, and DNA concentrations reaching 6018 ± 28 mg/L (306 mg/gVSSo), 2496 ± 103 mg/L (127 mg/gVSSo), 1822 ± 4 mg/L (93 mg/gVSSo), and 389 ± 3 mg/L (20 mg/gVSSo), respectively, after 155 min of thermal hydrolysis. Low levels of surfactants (10 and 50 mg/gVSSo) also led to a substantial increase in the readily biodegradable fraction of hydrolysed sewage sludge, reaching up to 90 %. Additionally, surfactant-assisted hydrolysed sewage sludge proved to be a favourable substrate for protease production using Bacillus licheniformis. The optimal enzymatic activity of 678 ± 14 U/mL was achieved when CTAC was added at a concentration of 10 mg/gVSSo. In summary, this study evaluated an innovative approach to enhance the solubilisation of biomolecules from sewage sludge using surfactant-assisted thermal hydrolysis. This methodology not only positively affected biodegradability but also proved to be suitable for potentially producing valuable industrial products like proteases through fermentation with B. licheniformis, thus offering a new strategy for the sustainable treatment of sewage sludge.

Impact of constant magnetic field on enhancing the microalgal biomass and biomolecules accumulations and life cycle assessment of the approach

Three freshwater microalgal species such as Chlorella protothecoides, Micractinium sp. and Scenedesmus obliquus were cultured under static magnetic field (SMF) and its influence on the accumulation of biomolecules (lipids, proteins, carbohydrates) and biomass production have been evaluated. This study involved the cultivation of the three microalgal species under the electromagnetic intensity of 80mT which was achieved using ferrite magnets. The SMF treatment showed a significant enhancement in biomass productivity of S. obliquus (0.098 g L−1 d−1) and C. protothecoides (0.114 g L−1 d−1). On compared to SMF untreated culture, Micractinium sp. resulted in a considerable reduction in biomass productivity by 10.9 % was observed. The constant SMF treatment for the total cultivation period (17 days) has significantly promoted the biomolecules accumulation (9 % lipids, 39 % protein, 16 % carbohydrates) and biomass (55 %) productivity of S. obliquus. The results suggested that SMF treatment exhibited a species-specific response in biomass productivity and biomolecules accumulation. Finally, to assess the feasibility of this strategy, economic feasibility and LCA simulation for SMF treated microalgal biomass and biomolecules production have been evaluated. LCA revealed that the magnetic field application for microalgal cultivation processes showed diversified impacts on environment as few indicators (Abiotic depletion, Acidification and Global warming) were better under magnetic application as compared to non-magnetic cultivation process.

Involvement of the Bacillus SecYEG Pathway in Biosurfactant Production and Biofilm Formation.

With Bacillus species, about 30% of extracellular proteins are translocated through the cytoplasmic membrane, coordinated by the Sec translocase. This system mainly consists of the cytoplasmic ATPase SecA and the membrane-embedded SecYEG channel. The purpose of this work was to investigate the effects of the SecYEG export system on the production of industrial biomolecules, such as biosurfactants, proteases, amylases, and cellulases. Fifty-two isolates of Bacillus species were obtained from traditional fermented foods and then characterized using molecular microbiology methods. The isolates secreted exoenzymes that included cellulases, amylases, and proteases. We present evidence that a biosurfactant-like molecule requires the SecA ATPase and the SecYEG membrane channel for its secretion. In addition, we showed that biomolecules involved in biofilm formation required the SecYEG pathway. This work presents a novel seven-target fragment multiplex PCR assay capable of identification at the species level of Bacillus through a unique SecDF chromosomal gene. The bacterial membrane protein SecDF allowed the discrimination of Bacillus subtilis, B. licheniformis, B. amyloliquefaciens, and B. sonorensis. SecA was able to interact with AprE, AmyE, and TasA. The Rose Bengal inhibitor of SecA crucially affected the interaction of AprE, AmyE, TapA, and TasA with recombinant Gst-SecA. The Rose Bengal prevented Bacillus species from secreting and producing proteases, cellulases, amylases, and biosurfactant-like molecules. It also inhibited the formation of biofilm cell communities. The data support, for the first time, that the SecYEG translocon mediates the secretion of a biosurfactant-like molecule.

Biosynthesis of biomolecules from saffron as an industrial crop and their regulation, with emphasis on the chemistry, extraction methods, identification techniques, and potential applications in human health and food: A critical comprehensive review

The dried stigmas of Crocus sativus, known as “Red Gold,” are highly prized for their nutritional and medicinal qualities. These qualities are due to the presence of apocarotenoids such as crocin, crocetin, safranal, and picrocrocin. The concentrations of biomolecules in saffron play a crucial role in determining its quality and commercial value. Ensuring the purity of saffron biomolecules is crucial for their pharmaceutical and food applications, given their significant potential in these fields. Enhancing cultivation practices and harnessing biosynthesis pathways through genetic engineering are widely used methods to boost the production of saffron biomolecules. Nevertheless, achieving optimal purity and output from the final products necessitates the implementation of efficient extraction methods. Additionally, employing effective identification methods is crucial for attaining accuracy in estimating the quality and quantity of these biomolecules. Hence, understanding the biosynthesis, extraction, and identification methods of saffron biomolecules, along with their significant role in human health and food, holds great importance. There is a need for extensive research to enhance the quality of components used in the food and pharmaceutical industries, surpassing the current studies. Thus, this review provides an overview of saffron biomolecules, including crocin, crocetin, safranal, and picrocrocin, along with their properties, biosynthesis, and regulation. Furthermore, the paper delves into the various aspects of saffron biomolecules, including sample preparation, extraction, identification, and quantification. In addition, the paper highlighted the possible health advantages and food uses of saffron biomolecules, as well as detailed information on the role of artificial intelligence have been discussed as a cutting-edge tool for studying various aspects of saffron biomolecules. Furthermore, the study has emphasized the future potential and opportunities for further research on saffron and its biomolecules, which can pique the interest of researchers, scientists, and industrial people seeking new and innovative opportunities.

Fed-batch fermentation of sugarcane biomass applied for biomolecules production in fluidized bed reactor

A production of xylitol and ethanol from a mixture of sugarcane straw and bagasse (biomass composed of 50 % m/m of both) hydrolysates was evaluated in a batch-fed column reactor. The biomass underwent acid hydrolysis, and the xylitol production process from hemicellulosic hydrolysate was assessed to determine the feasibility of operating four batches, showing conversions (YP/S of 0.28, 0.46, 0.57 and 0.47 g/g). Afterwards, alkaline pretreatment was performed, followed by enzymatic saccharification of the remaining biomass to obtain fermentable sugars for ethanol production. This involved operating five cycles, showing YP/S values of 0.14, 0.18, 0.24, 0.38 and 0.37 g/g, respectively. Additionally, the utilization of the black liquor generated from alkaline pretreatment was studied for reuse in subsequent pretreatments, demonstrating the feasibility of 4 cycles and thus, reducing the need for chemical preparation. The potential for maximizing the use of the main fractions of sugarcane biomass was confirmed.

Metabolic responses of Euglena gracilis under photoheterotrophic and heterotrophic conditions

The protist Euglena gracilis has various trophic modes including heterotrophy and photoheterotrophy. To investigate how cultivation mode influences metabolic regulation, the chemical composition of cellular metabolites of Euglena gracilis grown under heterotrophic and photoheterotrophic conditions was monitored from the early exponential phase to the mid-stationary phase using two different techniques, i.e, nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HRMS). The combined metabolomics approach allowed an in-depth understanding of the mechanism of photoheterotrophic and heterotrophic growth for biomolecule production. Heterotrophic conditions promoted the production of polar amino and oxygenated compounds such as proteins and polyphenol compounds, especially at the end of the exponential phase while photoheterotrophic cells enhanced the production of organoheterocyclic compounds, carbohydrates, and alkaloids.

Sub-pilot scale sequential microalgal consortium-based cultivation for treatment of municipal wastewater and biomass production

Municipal wastewater (MWW) was treated by a sequential pilot microalgal cultivation process. The cultivation was performed inside a specifically designed low-cost photobioreactor (PBR) system. A microalgal consortium 2:1 was developed using Tetraselmis indica (TS) and Picochlorum sp. (PC) in the first stage and PC:TS (2:1) in the second stage and the nutrient removal efficiency and biomass production and biomolecules production was evaluated and also compared with monoculture in a two-stage sequential cultivation system. This study also investigated the effect of seasonal variations on microalgae growth and MWW treatment. The results showed that mixed microalgal consortium (TS:PC) had higher nutrient removal efficiency, with chemical oxygen demand (COD), total phosphate (TP), and total nitrate (TN) removal efficiencies of 78.50, 84.49, and 84.20%, respectively, and produced a biomass of 2.50 g/L with lipid content of 37.36% in the first stage of cultivation under indoor conditions. In the second stage of indoor cultivation, the PC:TS consortium demonstrated maximum COD, TP, and TN removal efficiencies of 92.49, 94.24, and 94.16%, respectively. It also produced a biomass of 2.65 g/L with a lipid content of 40.67%. Among all the seasonal variations, mass flow analysis indicated that the combination of mixed consortium-based two-stage sequential process during the winter season favored maximum nutrient removal efficiency of TN i.e. 88.54% (84.12 mg/L) and TP i.e., 90.18% (43.29 mg/L), respectively. It also enhanced total biomass production of 49.10 g in 20-L medium, which includes lipid yield ∼15.68 g compared to monoculture i.e., 82.06% (78.70 mg/L) and 82.87% (40.26 mg/L) removal of TN and TP, respectively, and produced biomass 43.60 g with 11.90 g of lipids.

Enhancing soil health and carbon sequestration through phytogenic treatment: insights into microbial functional pathways in pasture dieback affected soil

Abstract Background and aims Phytogenic bioactive plant products have shown promise in mitigating Australian pasture dieback (PDB) syndrome, a complex condition that adversely affects pasture productivity and sustainability. PDB is characterised by the progressive decline of grass, resulting in reduced soil organic matter. Recent studies have indicated that soil microbial communities play a crucial role in the remediation of affected pastures. In our previous research, the application of a phytogenic secondary metabolic product demonstrated a positive impact on soil microbial diversity, and it significantly increased pasture biomass. Building upon our previous study, we aimed to further investigate the mechanisms underlying pasture improvement through phytogenic treatment by spraying. Methods Here, we conducted a shotgun metagenomic investigation of the soil microbiome functional pathways affected by the phytogenic treatment. Results The application of phytogenic treatment to the PDB-affected soil resulted in a notable increase in soil microbial functional richness and diversity and showed alterations in beta diversity. Among the 65 significantly altered functional pathways, 54 showed an increase, while 11 decreased in response to the phytogenic treatment. The treatment altered the soil’s functional capacity towards increased production of biomolecules, including amino acids, lipids, and cofactors, thus enhancing the soil’s nutritional value. Furthermore, the phytogenic treatment significantly increased pathways involved in soil detoxification and carbon sequestration, suggesting its potential to promote soil health and carbon storage. Conclusion Our findings contribute to a better understanding of the mechanisms involved in improving the soils affected by pasture dieback. These insights will help develop sustainable strategies for pasture production.

Biocatalytic Conversion of Carrageenans for the Production of 3,6-Anhydro-D-galactose.

Marine biomass stands out as a sustainable resource for generating value-added chemicals. In particular, anhydrosugars derived from carrageenans exhibit a variety of biological functions, rendering them highly promising for utilization and cascading in food, cosmetic, and biotechnological applications. However, the limitation of available sulfatases to break down the complex sulfation patterns of carrageenans poses a significant limitation for the sustainable production of valuable bioproducts from red algae. In this study, we screened several carrageenolytic polysaccharide utilization loci for novel sulfatase activities to assist the efficient conversion of a variety of sulfated galactans into the target product 3,6-anhydro-D-galactose. Inspired by the carrageenolytic pathways in marine heterotrophic bacteria, we systematically combined these novel sulfatases with other carrageenolytic enzymes, facilitating the development of the first enzymatic one-pot biotransformation of ι- and κ-carrageenan to 3,6-anhdyro-D-galactose. We further showed the applicability of this enzymatic bioconversion to a broad series of hybrid carrageenans, rendering this process a promising and sustainable approach for the production of value-added biomolecules from red-algal feedstocks.