Biotechnologia最新文献

Background and objective: Since plant-based natural drugs are widely accepted in modern times and possess numerous pharmacological effects with an extensive therapeutic range, an ethnomedicinal plant native to Bangladesh was selected to investigate for investigation of its various pharmacological effects. Macropanax dispermus has been traditionally used and has demonstrated numerous pharmacological effects in preclinical investigations. Therefore, this research aimed to assess the central nervous system (CNS) depressant and antioxidant activities of the crude methanol extracts of the stem barks (MDMS), leaves (MDML), and their different fractions.

Methods: The CNS depressant activity was assessed using the hole cross, rota-rod, and elevated plus maze tests on Swiss Albino mice, while the antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl free radical, hydrogen peroxide (H₂O₂) nonradical scavenging, and ferric reducing power assays.

Results: The conducted assays successfully demonstrated that the chloroform fraction of MDML is a significantly (P < 0.001) effective CNS depressant, muscle relaxant, and anxiolytic agent with excellent antioxidative effects compared to standard and control. The aqueous fraction of MDML also acted as a significantly (P < 0.001) active CNS depressant and muscle relaxant, and it was a highly active ferric-reducing agent. All effects were dose and concentration-dependent.

Conclusion: The presence of various phytochemicals might contribute to these activities. However, further research is suggested to isolate their active compounds and evaluate their mechanisms of action.

Background: Recombinant plasminogen activator (r-PA) consists of the Kringle-2 and protease domains of human tissue-type plasminogen. It is used clinically to treat coronary artery thrombosis and acute myocardial infarction. However, the expression and production of reteplase (r-PA) are limited due to its susceptibility to proteolysis during manufacturing processes. Therefore, efforts have been made to address this limitation.

Materials and methods: To enhance the conformational stability of r-PA and increase its resistance to proteolysis, we used Gly 6 Ala substitutions in the Kringle-2 domain through in silico . We created an in silico mutant collection with eight structures, incorporating four designated mutations (R103S, G39A, G53A, and G55A). Using MODELLER software and homology modeling, we developed three-dimensional structures for two Kringle-2 and tissue plasminogen activator protease domains, including the wild noncleavable form (R103S) and mutants with all four designated mutations. We assessed protein stability using a dynamic cross-correlation matrix by extracting global properties such as Root Mean Square Deviation (RMSD) and Root Mean Square Fluctuation (RMSF) from trajectory files.

Results: The findings revealed that a single glycine-alanine substitution (G39A) enhanced the conformational stability of r-PA, as evidenced by improvements in RMSD, RMSF, radius of gyration, surface accessibility, hydrogen bond formation, eigenvector projection, and density analysis.

Conclusion: The conformational stability of r-PA conferred by glycine replacement with alanine may decrease the propensity for proteolysis in protease - rich environments across various recombinant systems and potentially enhance its production and expression levels.

Nanotechnology presents an exciting opportunity in cancer research by offering significant advancements in therapies, diagnosis, and management. It possesses unparalleled potential to enhance the accuracy and effectiveness of cancer therapy while simultaneously reducing adverse effects, owing to its distinctive capability to manipulate matter at a molecular level. Using nanoparticle carriers has facilitated the precise administration of therapeutic agents to afflicted areas within the human body through customized drug delivery systems, resulting in improved treatment accuracy and efficacy while reducing adverse effects. These techniques improve drug solubility and stability, leading to elevated levels of biochemical availability and improved efficacy outcomes for patients with minimal negative effects during treatment cycles. Another use case for nanoparticles includes tumor imaging; functionalized with targeting ligands containing diagnostic agents, they foster early detection, making quicker remedial action plans possible. Overall, the incorporation of nanotechnology ensures a promising future, although it stresses the need to address regulatory hurdles and safety concerns before widespread clinical implementation. Despite the complexity of cancer research and patient care, nanotechnology shows promise in transforming both fields.

Screening for effective vaccines requires broad studies on their immunogenicity in vitro and ex vivo . We used a PBMC-based system to assess changes in CD4⁺ T cells, CD8⁺ T cells, and CD19⁺ B cells upon stimulation with different combinations of antigens and adjuvants. We studied the activation mechanism using flow cytometry and two different adenoviral adjuvants characterized by the presence or absence of costimulatory ligands for the ICOS and CD40 receptors. Our studies identified the cellular targets and molecular mechanisms driving ongoing switched-antibody diversification. Class-switched memory B cells were the main precursor cells (95.03% ± 0.38 vs. mock 82.33% ± 0.45, P < 0.05) after treatment with the immunogenic formula: adenovirus armed (MIX1) or not (MIX2) with the ICOS and CD40 ligand, the recombinant receptor binding domain (rRBD), and Lentifect™ SARS-CoV-2 spike-pseudotyped lentivirus (GeneCopoeia, USA). Bcell class-switching towards the IgG⁺IgM⁺- positive phenotypes was noted (~50-fold increase vs. mock, P < 0.05). A significant increase was observed in the CD8⁺T_EM population of the MIX1 (~2-fold, P < 0.05) and MIX2 (~4.7-fold, P < 0.05) treated samples. CD8⁺T_EMRA increased when PBMCs were treated with MIX2 (9.63% ± 0.90, P < 0.05) vs. mock (2.63% ± 1.96). Class-switched memory B cells were the dominant antigen-specific cells in primary reactions. We indicated a correlation between the protection offered by vaccine regimens and their ability to induce high frequencies of multifunctional T cells.

Plant growth regulators (PGRs) control signaling networks and developmental processes involved in plant responses to various biotic and abiotic stresses, making it crucial to study PGRs in vitro. The protocol for micropropagation of Solanum lycopersicum L., following callus induction and regeneration through explants such as internodal segments, leaves, and nodal segments, was established during the present study. Explants were inoculated on Murashige and Skoog (MS) medium supplemented with different plant growth regulators like BA (6-benzylaminopurine), 2,4-D (2,4-dichlorophenoxyacetic acid), BA + 2,4-D, IAA (Indoleacetic acid), IBA (Indolebutyric acid), and NAA (Naphthaleneacetic acid). It was observed that among all explants, the nodal segment showed maximum callus induction (83.33%) and multiplication (86.67%) at 0.25 mg/l of 2,4-D; the highest shoot number (3.33) at 0.5 mg/l of IAA + 0.5 mg/l of BA; the greatest shoot length (7.57 cm) at 0.75 mg/l of BA; root induction (80.95%), root number (21.88), and root length (10.62 cm) at 1 mg/l of IAA. Additionally, the maximum fresh weight (2.448 g) was observed at 0.5 mg/l of BA, while the highest dry weight (0.172 g) and dry matter content (14.25%) were noted at 1 mg/l of BA + 1 mg/l of 2,4-D for the internodal segment. Results of the present study revealed that among different explants, the best response was given by nodal segments, followed by internodal segments. Among the different PGRs, 2,4-D resulted in the highest callus induction and multiplication percentage.

The utilization of hydrolytic enzymes in various industrial processes worldwide has gained more attention than chemical catalysts due to the high selectivity of enzymes, their ease of control, and their negligible environmental impact, as they produce very small amounts of byproducts. Xylanase is one such enzyme that catalyzes the breakdown of the β-1,4 linkage of xylan, the second most abundant renewable heteropolysaccharide and hemicellulosic constituent of the plant cell wall. Naturally, xylanase can be obtained from various sources such as mollusks, insects, plants, animals, and various microorganisms (bacteria, fungi, yeast, and algae). The utilization of xylanase could greatly improve the overall economics of processing lignocellulosic materials for the generation of monosaccharides, liquid fuels, and chemicals. Microbial xylanase is suitable for applications in food and feed, paper and pulp, textile, pharmaceutical, and biorefining industries. It has gained global attention due to its substrate specificities, biochemical properties, and various biotechnological applications. This review focuses on xylanase production, sources, fermentation processes, modes of action, purification methods, and applications in various industries.

Probiotic bacteria are distinguished by their ability to produce various functional postbiotic metabolites. Therefore, this study aimed to explore the in vitro antioxidant, antidiabetic, and antibacterial properties of two postbiotics generated by Lactiplantibacillus plantarum O7S1 (Lpb. plantarum O7S1) during the fermentation process: cell-free supernatant (CFS) and exopolysaccharides (EPS). The antioxidant potential of these postbiotics was assessed using various radical scavenging assays and ferric-reducing antioxidant potential. The antidiabetic activity was evaluated through α-amylase inhibitory assays, while antibacterial activity was determined using agar well diffusion assays. The results of the present study revealed that CFS exhibited significant antioxidant and antidiabetic efficacy in contrast to EPS (P < 0.001). Specifically, CFS displayed remarkable scavenging ability against DPPH, hydroxyl, and superoxide radicals, with inhibition rates of 88.78, 78.91, and 34.85%, respectively, while EPS showed comparatively lower inhibition rates. Additionally, CFS demonstrated higher reducing activity (0.30 optical density units at 700 nm) and potent α-amylase inhibitory activity (95.87%) compared to EPS (67.17%) (P < 0.001). The agar well diffusion assay reported that CFS showed significant antimicrobial activity against both Gram-positive and Gram-negative pathogens, while no activity was observed with EPS. Furthermore, carbohydrate fermentation analysis indicated the strain's ability to metabolize various carbohydrates and their derivatives, potentially enhancing digestive health. These findings suggest that both CFS and EPS exhibit promising hypoglycemic, antioxidant, and antibacterial properties, making them potential candidates for incorporation into functional foods and pharmaceuticals aimed at preventing oxidative damage, diabetes, and pathogenic bacterial infections.

Cleistocalyx operculatus flower buds have been widely used in traditional medicine because of their rich content of bioactive constituents. In this study, we obtained seven solvent extracts from the flower buds and evaluated their total phenolic (TPC), flavonoid (TFC), tannin (TTC), triterpenoid saponin (TSC), and alkaloid (TAC) contents. We assessed antioxidant activities using the DPPH assay and also looked at antimicrobial and enzyme inhibitory effects. The water extract possessed the highest TPC (328.9 mg GAE/g extract), followed by ethanol, methanol, and hexane extracts (85.4-101.5 mg GAE/g extract). Chloroform, butanol, ethyl acetate, and ethanol extracts had high TSCs (245.4-287.2 mg OAE/g extract). The hexane extract was richest in TTC and TFC (32.7 mg CE/g extract and 81.1 mg QE/g extract, respectively). Ethanol and methanol extracts exhibited the strongest antioxidant activities (IC₅₀ values of 25.2 and 30.3 μg/ml, respectively), followed by the water extract (IC₅₀ of 40.2 μg/ml). The hexane extract displayed the most growth-inhibitory activity against Helicobacter pylori ATCC51932 and ATCC43504 strains and Salmonella enterica serovar Typhimurium ATCC13311 (MIC values of 0.06, 0.13, and 0.4 mg/ml, respectively). Moreover, the hexane extract revealed the strongest inhibition of H. pylori urease activity (IC₅₀ of 4.51 μg/ml), whereas the water and methanol extracts had potent inhibitory effects on α-glucosidase activity (IC₅₀ values of 9.9 and 15.1 μg/ml, respectively). These flower bud extracts could be used for health protection, especially in preventing bacterial infections and inhibiting enzymes associated with various human diseases. Further investigation into the application of C. operculatus flower buds in the food and pharmaceutical industries is necessary.

In this work, we evaluated the protective capacity of Spirulina platensis biomass in preserving Lactobacillus delbrueckii subsp. bulgaricus WDCM 00102. The L. bulgaricus strain was freeze-dried in the presence of S. platensis biomass and the freeze-dried samples were then stored at 5 and 25°C for varying periods. Subsequently, the samples were rehydrated and bacterial plate counts were determined. The results indicate that a concentration of 12% S. platensis biomass was highly effective in preserving L. bulgaricus. Commercial products with higher S. platensis biomass content exhibited greater protective capacity. While S. platensis biomass is well-known for its prebiotic properties, its protective role has not been previously reported or thoroughly explored. This study demonstrates the protective capacity of S. platensis biomass in preserving L. bulgaricus, a strain particularly sensitive to preservation processes.

Oxidative stress-related pathologies have guided the scientific community into delving into natural product-based research on plant-based metabolites. Plant secondary metabolites serve as a valid alternative in managing oxidative stress-related pathologies. In this study, we present the secondary metabolite constituents of the polar extract (PE) and nonpolar extract (NPE) from the leaves of Bryophyllum pinnatum. These constituents were determined through qualitative and quantitative phytochemical screening. The functional groups and structures of these metabolites were determined based on FTIR and GC-MS experiments, respectively. Antioxidant and free radical scavenging (FRS) activities were determined using standard methods, including phosphomolybdenum, FRAP, DPPH, HRSA, and reducing power assays, with comparisons made to the ascorbic acid (AA) standard. Through Pearson correlation analysis, we estimated the relationship between antioxidant and FRS activities. The DPPH results revealed IC50s of 380.104 ± 0.001, 16.763 ± 0.001, and 7.684 ± 0.003 μg/ml for NPE, AA, and PE, respectively, indicating a trend of PE > AA > NPE. However, all other experiments showed a trend of AA > PE > NPE in antioxidant and FRS activities. These results showed the potential antioxidant and FRS properties of both PE and NPE. Additionally, the correlation analysis indicated a strong positive correlation between the antioxidant and FRS activities of PE and NPE. The research results suggest high antioxidant and FRS activities of PE and validate the use of B. pinnatum in managing free radical-related pathologies.