BioTech最新文献

A continuous effort is needed to develop sustainable production methods for industrial platform chemicals. B. succiniciproducens, a natural succinic acid-producer, can metabolize five and six carbon atoms containing sugars in pure form as well as from agro-industrial wastes. In our work, we investigate the conversion of industrial by-products, apple pomace from apple juice production, and whey waste from milk processing to succinic acid and other organic acids (lactic, formic, and acetic acid). We obtained a succinic acid yield of 0.224 g/g total consumed fermentable sugars, lactic acid yield was 0.087 g/g, in turn, formic acid was produced at a 0.034 g/g yield, and acetic acid was obtained at 0.010 g/g total consumed fermentable sugars, using a thermal pretreated apple pomace-based medium. In the case of pretreated whey-based medium formulation, we obtained a succinic acid yield of 0.236 g/g consumed lactose, while formic acid and acetic acid were produced as well (0.09 g/g and 0.101 g/g, respectively). We demonstrate that lactose is a promising carbon source for organic acid production by B. succiniciproducens, while our study is the first to propose the use of a similarly available agro-industrial by-product, apple pomace, for the fermentative production of succinic acid by B. succiniciproducens.

The success of truffle cultivation is especially dependent on the quality of truffle-mycorrhized seedlings, which are typically produced in nurseries under aseptic conditions to avoid root colonization by undesired ectomycorrhizal fungi. However, such practices may also eliminate beneficial microorganisms that could support truffle symbiosis and improve seedling quality. In this study, twelve endophytic bacterial and fungal strains, isolated from the Tuber melanosporum environment (gleba tissue, mycorrhizae and truffle brûlé), were tested for their effect on T. melanosporum mycorrhization levels in inoculated Quercus ilex seedlings under nursery conditions. Co-inoculation with a strain of Agrobacterium tumefaciens significantly enhanced root colonization by T. melanosporum, supporting its potential role as mycorrhizal helper bacterium. In contrast, a strain of Trichoderma harzianum negatively affected mycorrhization. The remaining strains did not show significant effects on seedling mycorrhization or seedling growth. Our findings support the hypothesis that specific bacterial strains associated with truffles can act as mycorrhizal helper bacteria, highlighting the potential for co-inoculation strategies to enhance quality of truffle-inoculated seedlings in nurseries. However, further research is needed to gain a deeper understanding of the interactions within the mycorrhizosphere that could contribute to improving nursery seedling quality.

Extremophilic biological process (EBP) pretreatment increases substrate availability in anaerobic digestion, but the effect on downstream microbial community composition in industrial systems is not characterized. Changes in microbial communities were determined at an industrial facility processing dairy manure in a modified split-stream system with three reactor types: (1) EBP tanks at 70-72 °C; (2) mesophilic Continuously Stirred Tank Reactors (CSTRs); (3) mesophilic Induced Bed Reactors (IBRs) receiving combined CSTR and EBP effluent. All reactors had a two-day hydraulic retention time. Samples were collected weekly for 60 days. pH, volatile fatty acid and bicarbonate concentrations, COD, and methane yield were measured to assess tank environmental conditions. Microbial community compositions were obtained via 16S rRNA gene sequencing. EBP pretreatment increased acetate availability but led to a decline in the relative abundance of acetoclastic Methanosarcina species in downstream IBRs. Rather, syntrophic methanogens, e.g., members of Methanobacteriaceae, increased in relative abundance and became central to microbial co-occurrence networks, particularly in association with hydrogen-producing bacteria. Network analysis also demonstrated that these syntrophic relationships were tightly coordinated in pretreated digestate but absent in the untreated CSTRs. By promoting syntrophic methanogenesis while increasing acetate concentrations, EBP pretreatment requires system configurations that enable acetoclast retention to prevent acetate underutilization and maximize methane yields.

Hemp (Cannabis sativa L.) seed is progressively emerging as an innovative and sustainable source of plant oil. Defatted hempseed meal is rich in protein and carbohydrates, which bacteria can convert into cellulose using glucose and fructose. The optimal conditions for bacterial cellulose (BC) production from hempseed meal were evaluated by investigating total solid concentrations ranging from 8 to 16 °Brix using Komagataeibacter nataicola under controlled conditions. The changes in pH, bioactive compounds, organic acids, and carbon source concentrations were monitored during the fermentation process. The highest yield of BC, 12.41 g/L, was obtained at 10 °Brix after 14 days of fermentation. It was found that the production of BC was negatively impacted by a decrease in pH and an increase in organic acids. BC exhibited a ribbon-like 3D network structure and a crystallinity index of about 70%, with excellent water-holding capacity, low oil-holding capacity, high emulsifying activity, and high emulsion stability (11.21%, 2.71%, 34.33%, and 39.11%, respectively). This BC possesses exceptional mechanical properties, a high degree of crystallinity, and superior water-holding capacity, making it valuable in various industries such as food, pharmaceuticals, and biotechnology.

Neurosurgery is undergoing a significant transformation driven by advances in biomaterials and tissue engineering. These interdisciplinary innovations address challenges in repairing and regenerating neural tissues, integrating cranial and spinal implants, and improving patient outcomes. The incidence of neurological injuries such as traumatic brain injury and spinal cord injury remains high, underscoring the need for improved therapeutic strategies. This review provides a comprehensive overview of current biomaterial and tissue engineering approaches in neurosurgery, highlighting developments in neural tissue repair, cranial and spinal implants, spinal cord injury treatment, and peripheral nerve regeneration. Key challenges-such as ensuring biocompatibility, modulating the immune response, and bridging the gap between laboratory research and clinical application-are discussed. Emerging technologies including 3D bioprinting, nanotechnology (removing microfluidics), and microfluidics are examined for their potential to revolutionize neurosurgical treatments. The need for interdisciplinary collaboration among neurosurgeons, material scientists, and biologists is emphasized as critical for overcoming translational barriers and accelerating the clinical translation of these promising technologies.

Transgrafting constitutes a technique involving the integration of genetically modified (GM) and non-GM plant organisms. Typically, edible components derived from non-GM scions are categorized as non-GM food products, attributed to the absence of exogenous genetic material within their respective genomes. Non-GM food status could be compromised if proteins translocated across the graft interface. We investigated the movement of insecticidal Bacillus thuringiensis (Bt) crystal proteins, widely utilized in GM crop species. Tobacco plants engineered to express the Cry1Ab gene exhibited trace levels of Cry1Ab protein accumulation. In transgrafted plants, translocated Cry1Ab protein originating from GM rootstocks was detectable within scion foliar tissues but not within the seeds obtained from the non-GM scion. This result unequivocally demonstrates the capacity for Bt protein translocation from rootstocks to scions yet indicates a constrained distribution confined to scion tissues relatively close to the graft junction. While regulatory considerations necessitate a thorough appraisal of potential risks associated with Bt proteins, the results shown here facilitate the commercialization of the edible components as non-GM food products.

Regenerating sweet potato from field-derived plant material requires careful management of several critical factors, including the effectiveness of the disinfectant, the age of the explant, and the genotype used. In this context, establishing a reliable aseptic protocol is essential for successful in vitro culture. This study aimed to assess the effects of two disinfectants (sodium hypochlorite and mercuric chloride), three sweet potato genotypes (Nakabo, Boyapleu, and Irene), and three explant ages (2, 3, and 4 weeks) on clean culture establishment and regeneration efficiency from nodal explants. The findings revealed that regeneration success is significantly influenced by the type and concentration of disinfectant, explant age, and genotype. Treatment with 10% sodium hypochlorite markedly reduced contamination, achieving clean culture and regeneration rates of 75.72 ± 3.36% and 86.83 ± 3.02%, respectively, regardless of explant age. In contrast, higher concentrations of mercuric chloride induced necrosis in the explants. The highest clean culture rate (93.82 ± 1.16%) was observed in 3-week-old explants, which also showed a regeneration rate of 54.93 ± 3.19%. Furthermore, the Boyapleu and Irene genotypes demonstrated good suitability for in vitro culture, whereas the Nakabo genotype performed poorly under the tested conditions.

Industrial applications of xylanases in high-temperature settings are limited by enzyme instability. This study evaluated glycerol and phenolic compounds as modulators of the catalytic and structural properties of a recombinant Myceliophthora heterothallica endoxylanase (rMhXyn) expressed in Komagataella phaffii. Glycerol (20% v/v) significantly improved thermostability (5-fold increase in half-life at 55 °C), decreased the activation energy for catalysis, and enhanced structural rigidity as evidenced by molecular dynamics simulations (reduced RMSD and Rg). In contrast, phenolic acids provided only short-term stabilization at moderate temperatures and did not confer structural benefits. Enzyme kinetics revealed that glycerol enhanced catalytic turnover (↑V_max), while phenolic compounds modified both K' and cooperativity (Hill coefficient). Thermodynamic analysis supported glycerol's stabilizing effect, with increased ∆H_(D) and a positive shift in ∆S_(D). These results suggest glycerol as a superior stabilizer for rMhXyn in high-temperature bioprocesses such as lignocellulosic biomass hydrolysis. These findings highlight the potential of targeted additives to improve enzyme performance for biotechnological applications.

Herbal medicines can be promising for the treatment of infections caused by multidrug-resistant microorganisms. This study aimed to evaluate Rosmarinus officinalis (Rosemary) hydroalcoholic extract (RHE) regarding its phytochemical composition and potential for eliminating polymicrobial biofilm of Candida albicans with multidrug-resistant bacteria (Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa). The extraction and quantification of the extract (flavonoids and phenols) were performed, and its antioxidant activity (DPPH) and the presence of bio-active compounds were investigated using high-performance liquid chromatography with Diode Array Detection (HPLC-DAD) and Gas Chromatography-Mass Spectrometry (GC-MS). The minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) were determined, and the extract's action on polymicrobial biofilms was evaluated using the MTT assay. Data were analyzed using one-way ANOVA and Tukey's tests, as well as Kruskal-Wallis and Dunn's tests, with a significance level of 5%. RHE showed compatible amounts of flavonoids and phenols, with an EC50 of 19.53 µg/mL. Through HPLC-DAD and GC-MS, biomolecules such as rosmarinic acid and α-Pinene were identified. The extract exhibited microbicidal activity and antibiofilm action, with reduction percentages of up to 69.6% (p < 0.05), showing superior performance compared to 0.12% chlorhexidine against C. albicans + A. baumannii. In conclusion, RHE may be a promising therapeutic agent against multidrug-resistant pathogens.

The study of microalgae has led to significant progress in recent decades. The current microalgal biomass yield is unsatisfactory, except for certain species that are cultivated for the nutraceutical and pharmaceutical industries. In this study, the growth efficiency and biochemical composition of Tetradesmus obliquus at high levels of nutrients were characterized. Increasing the NH₄⁺-N content in the medium to 164 mg L^-1 allowed the algae to steadily accumulate biomass (6.14 ± 0.28 g L^-1) with a moderate content of starch. Optimizing the levels of N, P, and S allowed the biomass productivity to increase from the average 0.45 to 0.88 g L^-1 day^-1. A further increase of NH₄⁺-N to 410 mg L^-1 and other nutrients' concentration allowed the algae to accumulate biomass (7.50 ± 0.28 g L^-1), enriched with protein and pigments. The algae cultivated with the high load of nutrients reached 100%, 84%, and 96% removal of N, P, and S, respectively. Adding the NaHCO₃ to the photobioreactor for pH adjustment (instead of NaOH) did not significantly improve the growth parameters or affect the composition of the algal cells. In general, our study will improve the comprehensive understanding of culture-based approaches to study the perspective use of the alga T. obliquus.