Biotechnology for Biofuels最新文献

{"title":"Compatible traits of oleaginous Mucoromycota fungi for lignocellulose-based simultaneous saccharification and fermentation","authors":"Cristian Bolaño Losada,&nbsp;Ondrej Slaný,&nbsp;Dana Byrtusová,&nbsp;Boris Zimmermann,&nbsp;Svein Jarle Horn,&nbsp;Achim Kohler,&nbsp;Volha Shapaval","doi":"10.1186/s13068-025-02621-w","DOIUrl":"10.1186/s13068-025-02621-w","url":null,"abstract":"<div><h3>Background</h3><p>Mucoromycota fungi are promising for the production of second-generation biofuel from single-cell oils (SCOs) using lignocellulose biomass. Despite the lack of enzymatic capability for efficiently degrading lignocellulose in Mucoromycota fungi, simultaneous saccharification and fermentation (SSF) offers an attractive solution by combining enzymatic hydrolysis and fermentation in the same procedure. This study explored specific traits of various Mucoromycota species to evaluate their suitability for SSF, due to the frequent and significant gap between the microorganism and enzyme optimal conditions.</p><h3>Results</h3><p>The suitability of nine oleaginous fungal strains from the Mucoromycota phylum for use in lignocellulose-based simultaneous saccharification and fermentation was evaluated. Several traits, such as thermal tolerance, biochemical composition changes in response to incubation temperature, cellobiose and cellulose response and induction of β-glucosidase and endoglucanase, were evaluated. <i>Lichtheimia corymbifera</i> was the most suitable species for SSF due to its ability to grow up to 45 °C, with a consequent decrease in lipid unsaturation, and good uptake of cellobiose with induction of β-glucosidase and endoglucanase expression. The <i>Cunninghamella blackesleeana</i> and <i>Mucor circinelloides</i> strains were also considered good candidates; despite the cultivation should not exceed 35 °C, their good uptake of cellobiose and the expression of extracellular β-glucosidase induced by cellobiose indicated that they could increase the enzymatic hydrolysis efficiency. <i>C. blakesleeana</i> outperformed all the other tested strains in terms of β-glucosidase activity expression. In addition, both endoglucanase and β-glucosidase activities of <i>Rhizopus stolonifer</i> and <i>M. circinelloides</i> were induced by cellobiose. <i>Mortierella alpina</i> and <i>Mortierella hyalina</i> were not considered suitable for simultaneous saccharification and fermentation due to their reduced tolerance to high temperatures and poor response to cellobiose utilization.</p><h3>Conclusions</h3><p>This study identified beneficial traits of Mucoromycota species for simultaneous saccharification and fermentation using lignocellulose, contributing to an optimal selection for producing lipid-derived second-generation biofuels.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02621-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143481243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seed-specific expression of phosphatidate phosphohydrolases increases soybean oil content and seed weight","authors":"Beibei Chen,&nbsp;Jianwu Li,&nbsp;Shuaibing Yao,&nbsp;Geliang Wang,&nbsp;Xuemin Wang","doi":"10.1186/s13068-025-02620-x","DOIUrl":"10.1186/s13068-025-02620-x","url":null,"abstract":"<div><h3>Background</h3><p>Soybean is a major oil crop and a primary protein source for livestock, and soybean oil is the most common input for biodiesel. Identifying genes that enhance soybean yield and oil content is crucial for breeding programs. Phosphatidic acid (PA) phosphohydrolase (PAH), which dephosphorylates PA to diacylglycerol (DAG), plays a critical role in lipid synthesis, and yet their potential in improving agronomic traits of oil crops remains unexplored.</p><h3>Results</h3><p>This study shows that seed-specific expression of <i>AtPAH1/2</i> enhances PA turnover into DAG and triacylglycerol (TAG) accumulation in soybean seeds. <i>PAH</i> overexpression upregulated the expression of DAG acyltransferase (<i>DGAT</i>) but suppressed phospholipid: DAG acyltransferase (<i>PDAT</i>). In addition, seed-specific expression of <i>AtPAH1/2</i> increases soybean seed size and weight. Furthermore, analysis of the variation of the soybean PAHs in 4414 soybean accessions indicated that the advantageous effects of <i>GmPAH</i>s on oil content and seed weight were selected during domestication.</p><h3>Conclusion</h3><p>These findings suggest that targeting <i>PAH</i>s represents a promising strategy for enhancing soybean seed oil content and yield in current cultivars and landraces soybeans.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02620-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Target of Rapamycin is a crucial regulator of photosynthesis and nutrient metabolism partitioning in Nannochloropsis gaditana","authors":"Zhengying Zhang,&nbsp;Yanyan Li,&nbsp;Shu Yang,&nbsp;Shuting Wen,&nbsp;Hongmei Zhu,&nbsp;Hantao Zhou","doi":"10.1186/s13068-025-02617-6","DOIUrl":"10.1186/s13068-025-02617-6","url":null,"abstract":"<div><p>Utilizing microalgae as “photosynthetic cell factories” for compound production holds significant potential for sustainable carbon neutrality. However, the inherent inefficiency of algal photosynthesis, a limiting factor for productivity, represents a critical area for enhancement. Among the key regulatory mechanisms, the Target of Rapamycin (TOR), essential for cell growth regulation and known for its conserved structure across eukaryotes, remains underexplored in <i>Nannochloropsis gaditana</i>. In this study, we identified conserved component of the TOR complex in <i>N. gaditana</i>. Rapamycin (RAP) effectively inhibited photosynthetic growth and enhanced lipid accumulation in <i>N. gaditana</i>, as demonstrated by sensitivity tests. Transcriptomic analysis revealed that NgTOR modulates multiple intracellular metabolic and signaling pathways. Specifically, genes associated with photosynthesis and chlorophyll synthesis were significantly down-regulated following NgTOR inhibition. Additionally, genes involved in carbon metabolism, the TCA cycle, and amino acid biosynthesis were markedly reduced, while those related to lipid metabolism were up-regulated, resulting in stunted cell growth and increased lipid accumulation. Furthermore, blocking photosynthesis with DCMU significantly reduced the transcriptional activity of TOR-related complexes, highlighting a bidirectional regulatory interaction. These findings underscore the pivotal role of the TOR signaling pathway in regulating photosynthesis, carbon metabolism, and lipid metabolism in <i>N. gaditana</i>, setting the stage for further studies on photosynthetic autotrophy and lipid metabolic pathways in this species.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02617-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining transcriptomic and metabolomic insights into carbohydrate utilization by Ruminiclostridium papyrosolvens DSM2782","authors":"Mengcheng You,&nbsp;Zhenxing Ren,&nbsp;Letian Ye,&nbsp;Qiuyun Zhao,&nbsp;Ziyi Liu,&nbsp;Houhui Song,&nbsp;Chenggang Xu","doi":"10.1186/s13068-025-02619-4","DOIUrl":"10.1186/s13068-025-02619-4","url":null,"abstract":"<div><h3>Background</h3><p>Lignocellulose is the most abundant renewable bioresource on earth, and its biodegradation and utilization would contribute to the sustainable development of the global environment. <i>Ruminiclostridium papyrosolvens</i>, an anaerobic, mesophilic, and cellulolytic bacterium, produces an enzymatic complex known as the cellulosome. As one of the most highly evolved species among <i>Ruminiclostridium</i>-type species, <i>R. papyrosolvens</i> is particularly relevant for understanding how cellulolytic clostridia modulate their biomass degradation mechanisms in response to diverse carbon sources.</p><h3>Results</h3><p>Our study investigates the transcriptional responses of <i>Ruminiclostridium papyrosolvens</i> to different carbon sources to understand its lignocellulose utilization. Using RNA-seq, we analyzed gene expression under glucose, cellobiose, xylan, cellulose, and corn stover, identifying distinct metabolic preferences and regulatory responses. We found significant gene expression changes under corn stover compared to other carbon sources, with enrichment in ABC transporters and cell growth pathways. CAZyme gene expression was regulated by TCSs, affecting sugar transporter systems. Metabolic profiling showed <i>R. papyrosolvens</i> produced more complex metabolites during corn stover fermentation, revealing its adaptability to various carbon sources and implications for metabolic engineering.</p><h3>Conclusion</h3><p>This study not only uncovers the intricate response mechanisms of <i>R. papyrosolvens</i> to lignocellulose and its hydrolysates, but it also outlines the strategy for using <i>R. papyrosolvens</i> as a cellulolytic chassis in genetic engineering.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02619-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Discovery of a novel translation-machinery-associated protein that positively correlates with cellulase production","authors":"Kexuan Ma,&nbsp;Panpan Zhang,&nbsp;Jian Zhao,&nbsp;Yuqi Qin","doi":"10.1186/s13068-025-02624-7","DOIUrl":"10.1186/s13068-025-02624-7","url":null,"abstract":"<div><h3>Background</h3><p>The production of cellulases by filamentous fungi is a crucial aspect of sustainable bioproduction from renewable lignocellulosic biomass. Following the transcription of cellulase genes in the nucleus, a complex pathway involving translation, folding, and secretion is required to produce extracellular cellulases. Most studies about cellulase production have focused on examining transcriptional regulatory mechanisms and enhancement of enzyme gene levels; comparatively, little is known about protein translation and secretion for cellulase production.</p><h3>Results</h3><p>A translation-machinery-associated (TMA) protein PoTma15 was identified in cellulosic <i>Penicillium oxalicum</i>. The PoTma15 is conserved in various filamentous fungi, but not in yeast, plants, or animals. All homologous proteins of PoTma15 have previously been uncharacterized. PoTma15 was initially thought to be one of the putative interactors of transcription factor PoXlnR, as it was preyed by tandem affinity purification (TAP) coupled with the mass spectrometry (TAP–MS) technique using PoXlnR as the bait. Subsequent research revealed that PoTma15 is associated with the translation machinery. The top three proteins associated with PoTma15 are orthologs of <i>Saccharomyces cerevisiae</i> translation-machinery-associated protein (Tma19), translation elongation factor eIF5A, and ribosomal protein S28, respectively. PoTma15 is widely distributed in fungal hyphae and positively correlates with the production of cellulases and extracellular proteins. Deleting the Po<i>tma15</i> gene (Δ<i>tma15</i>) decreased cellulase production, while overexpressing the Po<i>tma15</i> gene (OE<i>tma15</i>) increased cellulase production. However, the Δ<i>tma15</i> mutant was not observed to have downregulated transcript levels of major (hemi)cellulase and amylase genes, compared to the <i>P</i>. <i>oxalicum</i> wild type (WT). The production of extracellular cellulases and extracellular proteins of the Δ<i>tma15</i> mutant was less affected by cycloheximide, an inhibitor of eukaryotic translation elongation, compared to the WT strain and OE<i>tma15</i> mutant<i>,</i> suggesting a stronger resistance to the translation-inhibiting effects of cycloheximide in the Δ<i>tma15</i> mutant. The results demonstrate that PoTma15 is a translation-machinery-associated protein that affects translation elongation and, consequently, the production of enzyme proteins.</p><h3>Conclusions</h3><p>PoTma15 is the first TMA protein characterized in cellulosic filamentous fungi and the first TMA protein used in fungi to increase cellulase production. PoTma15’s role in the production of cellulases and total extracellular proteins suggests that not only can it be used to widen the cellulase production pathway, but can even be engineered as a target to improve the production of other heterologous protein or bioproducts using filamentous fungi as cell factories in the future.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02624-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural changes and cellulose ultrastructure mapped with electron microscopy and SAXS after enzymatic hydrolysis of mildly steam pretreated Norway spruce","authors":"Maria E. F. Brollo,&nbsp;Fabio Caputo,&nbsp;Polina Naidjonoka,&nbsp;Lisbeth Olsson,&nbsp;Eva Olsson","doi":"10.1186/s13068-025-02616-7","DOIUrl":"10.1186/s13068-025-02616-7","url":null,"abstract":"<div><h3>Background</h3><p>The efficient use of softwood in biorefineries requires harsh pretreatment conditions to overcome biomass recalcitrance. While this allows the solubilization of hemicellulose, it also leads to the formation of compounds that act inhibitory against microorganisms during the fermentation step. To improve the efficacy of biomass utilization and identify optimal processing conditions, we evaluated the microstructural alterations occurring during pretreatment and enzymatic hydrolysis in Norway spruce. The biomass was steam pretreated at six different severities defined by two different temperatures (180 °C and 210 °C), with and without the addition of various acids (HAc, H₃PO₄, H₂SO₄, SO₂). After pretreatment, the materials were enzymatically hydrolysed using a cellulolytic cocktail (Celluclast + Novozym188) supplemented with a hemicellulolytic cocktail (Ultraflo). Scanning electron microscopy and small angle X-ray scattering were utilized to evaluate the structural changes, of the differently steam pretreated materials, before and after the enzymatic hydrolysis.</p><h3>Results</h3><p>Scanning electron microscopy revealed increased surface roughness and pore enlargement in all the materials after enzymatic hydrolysis. The higher the severity of the pretreatment, the more the surface was rough since it was easier for the enzymes to access the binding site. As revealed by small angle X-ray scattering (SAXS), increasing the enzymatic hydrolysis of hemicellulose did not result in further collapse of cellulose. In line with the SAXS result, a qualitative evaluation of the cellulose surface using Congo red showed a larger exposed cellulose surface area after enzymatic hydrolysis.</p><h3>Conclusions</h3><p>The present study reports the microstructural changes caused by pretreatment and enzymatic hydrolysis of Norway spruce. By enzymatically increasing the hemicellulose hydrolysis, the exposed cellulose surface area increases meaning that the cellulose might be easier to access for the enzymes. Structural analysis of biomass after enzymatic hydrolysis can direct the choice of enzymes for improved saccharification efficiency.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02616-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of microalgal β-carotene and astaxanthin: exploring their health-promoting properties under the effect of salinity and light intensity","authors":"Aditi,&nbsp;Rupesh Bhardwaj,&nbsp;Ankush Yadav,&nbsp;Prashant Swapnil,&nbsp;Mukesh Meena","doi":"10.1186/s13068-025-02612-x","DOIUrl":"10.1186/s13068-025-02612-x","url":null,"abstract":"<div><p>Microalgae are promising sources of valuable carotenoids like β-carotene and astaxanthin with numerous health benefits. This review summarizes recent studies on producing these carotenoids in microalgae under different salinity and light-intensity conditions, which are key factors influencing their biosynthesis. The carotenoid biosynthesis pathways in microalgae, involving the methylerythritol phosphate pathway in chloroplasts, are described in detail. The effects of high salinity and light stress on stimulating astaxanthin accumulation in species like <i>Haematococcus pluvialis</i> and <i>Chromochloris zofingiensis</i> and their synergistic impact are discussed. Similarly, the review covers how high light and salinity induce β-carotene production in <i>Dunaliella salina</i> and other microalgae. The diverse health-promoting properties of astaxanthin and β-carotene, such as their antioxidant, antiinflammatory, and anticancer activities, are highlighted. Strategies to improve carotenoid yields in microalgae through environmental stresses, two-stage cultivation, genetic engineering, and metabolic engineering approaches are evaluated. Overall, this review highlights advancements in β-carotene and astaxanthin production reporting the different microalgal capability to produce carotenoids under different stress level like 31.5% increase in β-carotene accumulation in <i>Dunaliella salina</i> and astaxanthin productivity reaching 18.1 mg/L/day in <i>Haematococcus lacustris</i>. It also explores novel biotechnological strategies, including CRISPR–Cas9, for enhancing carotenoid yield.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02612-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lactic whey as a potential feedstock for exopolysaccharide production by microalgae strain Neochloris oleoabundans UTEX 1185","authors":"Daniel Moisés Paredes-Molina,&nbsp;Miguel A. Cervantes-López,&nbsp;Domancar Orona-Tamayo,&nbsp;Nancy E. Lozoya-Pérez,&nbsp;Flora I. Beltrán-Ramírez,&nbsp;Juan Vázquez-Martínez,&nbsp;Karla L. Macias-Sánchez,&nbsp;Sergio Alonso-Romero,&nbsp;Elizabeth Quintana-Rodríguez","doi":"10.1186/s13068-024-02595-1","DOIUrl":"10.1186/s13068-024-02595-1","url":null,"abstract":"<div><h3>Background</h3><p>Lactic whey, a significant agro-industrial byproduct, poses environmental risks due to its chemical composition. Despite various valorization efforts, effective utilization remains a challenge. This study explores the potential of <i>Neochloris oleoabundans</i>, a microalgae known for its metabolic versatility and resilience to adverse conditions, to produce exopolysaccharides (EPS) using lactic whey as a substrate. We compared EPS production from lactose, the primary sugar in whey, with whole lactic whey. Characterization of the EPS was performed using Fourier transform infrared spectroscopy (FT-IR) and gas chromatography–mass spectrometry (GC–MS), while morphological analysis was conducted via scanning electron microscopy (SEM). This research aims to assess the feasibility of converting lactic whey into valuable EPS, providing a sustainable approach to managing this agro-industrial waste.</p><h3>Results</h3><p>Lactic whey has produced the highest EPS and the FT-IR spectra revealed structural variations in the monomers which compose these polymers. Galactose and glucose were shown to be the primary monomers, according to GC–MS EPS analysis. SEM revealed a homogenous matrix and <i>N. oleoabundans</i>'s bioflocculant characteristics.</p><h3>Conclusions</h3><p>Microalgae <i>N. oleoabundans</i> can produce EPS using lactic whey as feedstock and it has the potential to be employed as a wastewater treatment.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-024-02595-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Newly isolated halotolerant Gordonia terrae S-LD serves as a microbial cell factory for the bioconversion of used soybean oil into polyhydroxybutyrate","authors":"Song Xu,&nbsp;Ruiqin Han,&nbsp;Lidan Tao,&nbsp;Zhipeng Zhang,&nbsp;Junfei Gao,&nbsp;Xinyuan Wang,&nbsp;Wei Zhao,&nbsp;Xiaoxia Zhang,&nbsp;Zhiyong Huang","doi":"10.1186/s13068-025-02613-w","DOIUrl":"10.1186/s13068-025-02613-w","url":null,"abstract":"<div><p>Polyhydroxybutyrate (PHB) is a class of biodegradable polymers generally used by prokaryotes as carbon sources and for energy storage. This study explored the feasibility of repurposing used soybean oil (USO) as a cost-effective carbon substrate for the production of PHB by the strain <i>Gordonia terrae</i> S-LD, marking the first report on PHB biosynthesis by this rare actinomycete species. This strain can grow under a broad range of temperatures (25–40 ℃), initial pH values (4–10), and salt concentrations (0–7%). The findings indicate that this strain can synthesize PHB at a level of 2.63 ± 0.6 g/L in a waste-containing medium containing 3% NaCl within a 3 L triangular flask, accounting for 66.97% of the cell dry weight. Furthermore, ¹H NMR, ¹³C NMR, and GC–MS results confirmed that the polymer was PHB. The thermal properties of PHB, including its melting (T_m) and crystallization (T_c) temperatures of 176.34 °C and 56.12 °C respectively, were determined via differential scanning calorimetry analysis. The produced PHB was characterized by a weight-average molecular weight (M_w) of 5.43 × 10⁵ g/mol, a number-average molecular weight (M_n) of 4.00 × 10⁵ g/mol, and a polydispersity index (PDI) of 1.36. In addition, the whole genome was sequenced, and the PHB biosynthetic pathway and quantitative expression of key genes were delineated in the novel isolated strain. In conclusion, this research introduces the first instance of polyhydroxyalkanoate (PHA) production by <i>Gordonia terrae</i> using used soybean oil as the exclusive carbon source, which will enrich strain resources for future PHB biosynthesis.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02613-w","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Insight into the role of antioxidant in microbial lignin degradation: Ascorbic acid as a fortifier of lignin-degrading enzymes","authors":"Aipeng Li,&nbsp;Weimin Wang,&nbsp;Shuqi Guo,&nbsp;Changzhi Li,&nbsp;Xinying Wang,&nbsp;Qiang Fei","doi":"10.1186/s13068-025-02614-9","DOIUrl":"10.1186/s13068-025-02614-9","url":null,"abstract":"<div><h3>Background</h3><p>Microbial-driven lignin depolymerization has emerged as a promising approach for lignin degradation. However, this process is hindered by the limited activity of lignin-degrading enzymes. Antioxidants are crucial for maintaining redox homeostasis in living cells, which can impact the efficiency of enzymes. Ascorbic acid (AA) is well-known for its antioxidant properties, while <i>Trametes versicolor</i> is a commonly used lignin-degrading fungus capable of secreting laccase (Lac) and manganese peroxidase (MnP). Thus, AA was selected as model antioxidant and added into the culture medium of <i>T. versicolor</i> to examine the effect of antioxidants on the activity of lignin-degrading enzymes in the fungus.</p><h3>Results</h3><p>The presence of AA resulted in a 4.9-fold increase in the Lac activity and a 3.9-fold increase in the MnP activity, reaching 10736 U/L and 8659 U/L, respectively. This increase in enzyme activity contributed to a higher lignin degradation rate from 17.5% to 35.2%, consistent with observed morphological changes in the lignin structure. Furthermore, the addition of AA led to a reduction in the molecular weights of lignin and an increase in the content of degradation products with lower molecular weight, indicating more thorough degradation of lignin. Proteomics analysis suggested that the enhancement in enzyme activity was more likely to attributed to the reinforcement of AA on oxidative protein folding and transportation, rather than changes in enzyme expression.</p><h3>Conclusions</h3><p>The addition of AA enhanced the performance of enzymes responsible for lignin degradation in terms of enzyme activity, degradation rate, lignin structural change, and product mapping. This study offers a feasible strategy for enhancing the activity of lignin-degrading enzymes in the fungus and provides insights into the role of antioxidant in microbial lignin degradation.</p></div>","PeriodicalId":494,"journal":{"name":"Biotechnology for Biofuels","volume":"18 1","pages":""},"PeriodicalIF":6.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://biotechnologyforbiofuels.biomedcentral.com/counter/pdf/10.1186/s13068-025-02614-9","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143361980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}