BioTech最新文献

Microorganisms from saline environments have garnered significant interest due to their unique adaptations, which enable them to thrive under high-salt conditions and synthesize valuable biomolecules. This study investigates the biosynthesis of biomolecules, such as extracellular hydrolytic enzymes, biosurfactants, and carotenoid pigments, by four newly halotolerant bacterial strains isolated from saline environments in the Băicoi (soil, water) and Curmătura (mud) area (Prahova County, Romania). Isolation was performed on two selective culture media with different NaCl concentrations (1.7 M, 3.4 M). Based on their phenotypic and molecular characteristics, the four halotolerant bacteria were identified as Halomonas elongata SB8, Bacillus altitudinis CN6, Planococcus rifietoensis CN8, and Halomonas stenophila IB5. The two bacterial strains from the Halomonas genus exhibited growth in MH medium containing elevated NaCl concentrations (0-5 M), in contrast to the other two strains from Bacillus (0-2 M) and Planococcus (0-3 M). The growth of these bacteria under different salinity conditions, hydrocarbon tolerance, and biomolecule production were assessed through biochemical assays, spectrophotometry, and high-performance thin-layer chromatography. The antimicrobial properties of biosurfactants and carotenoids produced by H. elongata SB8, B. altitudinis CN6, P. rifietoensis CN8, and H. stenophila IB5 were evaluated against four reference pathogenic microorganisms from the genera Escherichia, Pseudomonas, Staphylococcus, and Candida. H. elongata SB8 showed the highest hydrocarbon tolerance. B. altitudinis CN6 exhibited multiple hydrolase activities and, along with H. elongata SB8, demonstrated biosurfactant production. P. rifietoensis CN8 produced the highest carotenoid concentration with antifungal and antimicrobial activity. Exploring these organisms opens new pathways for bioremediation, industrial bioprocessing, and sustainable biomolecule production.

Interspecific and intersectional crosses have introduced valuable genetic traits for blueberry (Vaccinium sect. Cyanococcus) cultivar improvement. Introgression from Vaccinium species at the diploid, tetraploid, and hexaploid levels has been found in cultivated blueberries. Continued efforts to integrate wild blueberry genetic resources into blueberry breeding are essential to broaden the genetic diversity of cultivated blueberries. However, performing heteroploid crosses among Vaccinium species is challenging. Polyploid induction through tissue culture has been useful in bridging ploidy barriers. Mixoploid or chimeric shoots often are produced, along with solid polyploid mutants. These chimeras are mostly discarded because of their genome instability and the difficulty in identifying periclinal mutants carrying germline mutations. Since induced polyploidy in blueberries often results in a low frequency of solid mutant lines, it is important to recover solid polyploids through chimera dissociation. In this study, two vegetative propagation methods, i.e., axillary and adventitious shoot induction, were evaluated for their efficiency in chimera dissociation. Significantly higher rates of chimera dissociation were found in adventitious shoot induction compared to axillary shoot induction. Approximately 89% and 82% of the adventitious shoots induced from mixoploid lines 145.11 and 169.40 were solid polyploids, respectively, whereas only 25% and 53% of solid polyploids were recovered through axillary shoot induction in these lines. Effective chimera dissociation provides useful and stable genetic materials to enhance blueberry breeding.

Lacticaseibacillus rhamnosus (L. rhamnosus) is a safe probiotic with no side effects, providing benefits such as gut microbiota regulation and immune enhancement, making it highly valuable with strong potential. However, strains from different sources have unique traits, and whole-genome sequencing (WGS) helps analyse these differences. In this study, we used WGS to examine L. rhamnosus strains from mice with fish oil-treated smoking-induced pneumonia to better understand their biological functions and explore possible anti-inflammatory mechanisms.

Methods: We isolated a strain, Lacticaseibacillus rhamnosus CP-1 (L. rhamnosus CP-1), from mice intestines where fish oil alleviated smoking-induced pneumonia. Identification of probiotic-related genes by WGS and characterised the strain's probiotic properties.

Results: L. rhamnosus CP-1 has a single circular chromosome (2,989,570 bp, 46.76% GC content) and no plasmids. COG, GO, and KEGG databases revealed genes linked to carbohydrate metabolism. The CAZy database identified GH25 lysozyme and PL8 polysaccharide lyase genes. KEGG highlighted an antimicrobial peptide ABC transporter permease, while TCDB noted the ABC-type antimicrobial peptide transporter (the main active transport component). KEGG also showed 10 genes for terpenoid skeleton biosynthesis and 5 for keto-glycan unit biosynthesis. Additionally, L. rhamnosus CP-1 carries metabolic regulators and bacteriocin-related genes.

Conclusions: Whole-genome sequencing analysis revealed that L. rhamnosus CP-1 has carbohydrate utilisation and potential anti-inflammatory effects at the molecular level. Potential functional genes include carbohydrate transport and hydrolase, antimicrobial peptide ABC transporter and its osmotic enzyme components, bacteriocin immune protein, terpenoid skeleton, and keto-glycan synthesis.

Nanobiotechnology applications in plant tissue culture have improved the development and physiology of explants, resulting in plants with high genetic homogeneity and phytosanitary quality. Silver nanoparticles (AgNPs) are well-known for their microbicidal properties, but their biochemical effects on plants require further exploration. In this work, green-synthesized AgNPs were evaluated in strawberry in vitro culture, photosynthetic pigment production, and acclimatization. AgNPs produced by Lysinibacillus fusiformis were characterized. Strawberry explants were grown in vitro on MS medium with 0, 100, 200, and 300 mg L^-1 AgNPs at 24 ± 2 °C and a photoperiod of 16:8 h light/dark. Shoot height and number, number of leaves, number of roots, and root length were evaluated, and chlorophyll (a, b, and total) was quantified. Rooted shoots were acclimatized ex vitro on substrates containing 0 and 200 mg L^-1 AgNPs. The results showed that low AgNPs concentrations had a positive impact on shoot multiplication, development, and rooting, but at higher concentrations, the effects decayed. However, chlorophyll production improved with increasing AgNP concentration. Shoots treated with AgNPs showed higher ex vitro survival. Our study has direct implications for the profitability and sustainability of commercial strawberry production.

Microalgae represent promising biotechnological platforms for bioactive compound production with pharmaceutical applications. This study investigated the phytochemical composition and biological activities of lipid extracts from three Chlorella species to evaluate their potential as antioxidant and antidiabetic sources. Lipid extraction using chloroform-methanol (2:1) followed by GC-MS analysis revealed distinct compound distributions: 29 compounds in C. ellipsoidea, 33 in C. sorokiniana, and 19 in C. vulgaris. Major bioactive compounds included 2-hexanol, 1,3,6-heptatriene, 4-(2,3-dimethyl-2-cyclopenten-1-yl)-4-methylpentanal, n-hexadecanoic acid, and octadecanoic acid. Biological activity screening encompassed antioxidant assessment through DPPH• and •NO radical scavenging assays and FRAP analysis, while antidiabetic potential was evaluated using α-glucosidase and α-amylase inhibition assays. C. sorokiniana exhibited superior bioactivity with the highest antioxidant capacity (DPPH• IC₅₀ = 329.03 ± 4.30 µg/mL; •NO IC₅₀ = 435.53 ± 10.20 µg/mL; FRAP = 94.74 ± 5.72 mg TE/g) and strongest enzyme inhibition (α-glucosidase IC₅₀ = 752.75 ± 57.95 µg/mL; α-amylase IC₅₀ = 3458.50 ± 104.01 µg/mL). This is the first report on C. sorokiniana strain KU.B2's biological properties and phytochemical profile. These findings establish C. sorokiniana as a valuable biotechnological platform for pharmaceutical bioactive compound development.

Venturia inaequalis, the cause of apple scab, readily develops resistance to fungicides with specific modes of action. Knowledge of the spatial and temporal pattern of resistance development is therefore relevant to fruit producers and their consultants. In the Lower Elbe region of Northern Germany, a two-year survey based on a conidial germination test was conducted, examining fungicide resistance in 35 orchards under Integrated Pest Management (IPM), 16 orchards of susceptible cultivars as well as a further 12 orchards of scab-resistant (Vf) cultivars under organic management, and 34 abandoned or unmanaged sites. No evidence of resistance to SDHI compounds (fluopyram, fluxapyroxad) was found after >5 yr of their regular use. Resistance to anilinopyrimidines (cyprodinil, pyrimethanil) had disappeared 15 yr after its widespread occurrence. Isolates from a few IPM orchards showed a reduced sensitivity to dodine. Double resistance to the MBC compound thiophanate-methyl and the QoI trifloxystrobin was rare in V. inaequalis strains that had achieved breakage of Vf-resistance, but very common (>50%) on scab-susceptible cultivars in IPM, organic and abandoned orchards in the 'Altes Land' core area of the Lower Elbe region, and in IPM orchards in the periphery. We conclude that resistance to QoI and MBC fungicides is persistent even decades after their last use, and that the core area harbours a uniform population adapted to intensive crop protection, whereas isolated orchards in the periphery are colonised by discrete populations of V. inaequalis.

Investigating the functional interactions between rumen microbial fermentation and epithelial mitochondrial dynamics/energy metabolism in Tibetan sheep at different altitudes, this study examined ultrastructural changes in rumen epithelial tissues, expression levels of mitochondrial dynamics-related genes (fusion: Mfn1, Mfn2, OPA1, Mic60; fission: Drp1, Fis1, MFF), and ketogenesis pathway genes (HMGS2, HMGCL) in Tibetan sheep raised at three altitudes (TS 2500m, TS 3500m, TS 4500m). Correlation analysis was performed between rumen microbiota/metabolites and mitochondrial energy metabolism. Results: Ultrastructural variations were observed across altitudes. With increasing altitude, keratinized layer became more compact; desmosome connections between granular layer cells increased; mitochondrial quantity and distribution in spinous and basal layers increased. Mitochondrial dynamics regulation: Fission genes (FIS1, DRP1, MFF) showed significantly higher expression at TS 4500m (p < 0.01); fusion genes (Mfn1, OPA1) exhibited altitude-dependent upregulation. Energy metabolism markers: Pyruvate (PA) decreased significantly at TS 3500m/TS 4500m (p < 0.01); citrate (CA) increased with altitude; NAD⁺ peaked at TS 3500m but decreased significantly at TS 4500m (p < 0.01); Complex II (SDH) and Complex IV (CO) activities decreased at TS 4500m (p < 0.01). Ketogenesis pathway: β-hydroxybutyrate increased significantly with altitude (p < 0.01); acetoacetate peaked at TS 2500 m/TS 4500 m; HMGCS2 expression exceeded HMGCL, showing altitude-dependent upregulation at TS 4500m (p < 0.01). Microbiome-metabolism correlations: Butyrivibrio_2 and Fibrobacter negatively correlated with Mic60 (p < 0.01); Ruminococcaceae_NK4A214_Group positively correlated with Mfn1/OPA1 (p < 0.05); WGCNA identified 17 metabolite modules, with MEturquoise module positively correlated with DRP1/Mfn2/MFF (p < 0.05). Conclusion: Altitude-induced ultrastructural adaptations in rumen epithelium correlate with mitochondrial dynamics stability and ketogenesis upregulation. Mitochondrial fission predominates at extreme altitudes, while microbiota-metabolite interactions suggest compensatory energy regulation mechanisms.

The emergence of antimicrobial resistance (AMR) in Clostridium difficile (C. difficile), particularly to last-line antibiotics such as linezolid, represents a critical challenge in clinical settings. This study investigates the genomic epidemiology of linezolid-resistant C. difficile, focusing on the distribution and mutational patterns of the chloramphenicol-florfenicol resistance (cfr) gene and its association with multidrug resistance. We analyzed 514 clinical isolates (354 from NCBI Pathogen Detection, 160 from EnteroBase), revealing distinct prevalence patterns among cfr subtypes: cfr(C) was dominant (156/354 NCBI strains; 101/160 EnteroBase strains), whereas cfr(B) frequently harbored missense mutations (p.R247K, p.V294I, and less commonly p.A334T). The cfr(E) subtype was exclusively identified in ribotype 027 (RT027) strains. Notably, cfr(C) exhibited a strong association with RT017, correlating with a conserved 99 bp genomic deletion. Phylogenetic analysis linked cfr-carriage to predominant sequence types (ST1 in NCBI strains, ST37 in EnteroBase isolates). Furthermore, the co-occurrence of cfr with additional AMR genes conferred resistance to macrolides (erythromycin, azithromycin) and tetracyclines, indicating a convergent evolution toward multidrug resistance. These findings underscore the interplay between cfr mutations, hypervirulent ribotypes, and AMR dissemination, necessitating enhanced surveillance to mitigate the spread of resistant C. difficile lineages.

Limnospira spp., commercially known as spirulina, is widely recognized for its remarkable benefits due to its rich composition of bioactive compounds like phycobiliproteins, carotenoids, and phenolic compounds. These natural bioactive compounds not only serve as colorants but also offer potent antioxidant, anti-inflammatory, immunomodulatory, anticancer, antimicrobial, and anti-aging properties. As a result, spirulina and its components are increasingly used in cosmetic formulations to promote skin hydration, reduce wrinkles, and protect against UV radiation damage. Its bioactive components enhance fibroblast growth, boost collagen production, and prevent premature skin aging by inhibiting enzymes responsible for elastin degradation. Additionally, spirulina-based cosmetics have demonstrated wound-healing properties without genotoxic effects, with formulations containing C-phycocyanin particularly effective in shielding skin cells from UV-induced apoptosis. Despite these well-established benefits, there remains significant potential for the cosmetic industry to harness spirulina's capabilities further. Research into the molecular mechanisms underlying its bioactive compounds in cosmetic formulations is still in its early stages, offering many opportunities for innovation. Emerging fields of biotechnology, such as nanotechnology and biocosmetics, could enhance the stability, efficacy, and delivery of spirulina-based ingredients, unlocking new possibilities for skin protection and rejuvenation. Furthermore, its proven biological properties align perfectly with the increasing consumer demand for safe, sustainable, and nature-inspired skincare solutions.

Broomrapes (Orobanche and Phelipanche spp.) are parasitic weeds that significantly impact the productivity of major crops in the Mediterranean region, like tomato (Solanum spp.) and faba bean (Vicia faba) species. This review article extensively discusses management strategies to control broomrapes, which range from preventive measures to curative approaches. Additionally, it includes meaningful information on the intricate molecular mechanisms underlying the broomrape-host interaction, focusing on the host recognition of parasitic plant molecular patterns and the hormonal crosstalk that regulates the establishment of parasitism. Moreover, this article highlights the potential of breeding for resistance in cultivated crops, such as tomato and faba bean, as a sustainable, long-term solution to combat broomrape infestation. This review serves as a valuable resource for both researchers and farmers, offering insights for developing, implementing, and adapting effective and environmentally sustainable management practices for broomrape in Mediterranean agricultural systems.