BMC Biotechnology最新文献

Background: Dendrobium catenatum is a perennial herb of the genus Dendrobium orchidaceae. It has been known as "Golden Grass, Soft Gold" since ancient times with effects of strengthening the body, benefiting the stomach, generating body fluid, nourishing Yin and clearing internal heat. The flowers of D. catenatum have anti-oxidation, immune regulation and other biological activities. The composition analysis of flowers showed that flavonoid glycosides were significantly accumulated in floral tissue. However, in the flowers of D. catenatum, there was only one case of the UDP-glycosyltransferase (UGT) responsible for the glycosylation of flavonoids has been reported.

Result: In this study, a new UGT (named UGT708S6) was cloned from D. catenatum flowers rich in O-glycosides and C-glycosides, and its function and biochemical properties were characterized. Through homology comparison and molecular docking, we identified the key amino acid residues affecting the catalytic function of UGT708S6. The glycosyltransferase UGT708S6 was characterized and demonstrated C-glycosyltransferase (CGT) activity in vitro assay using phloretin and 2-hydroxynaringenin as sugar acceptors. The catalytic promiscuity assay revealed that UGT708S6 has a clear sugar donor preference, and displayed O-glycosyltransferase (OGT) activity towards luteolin, naringenin and liquiritigenin. Furthermore, the catalytic characteristics of UGT708S6 were explored, shedding light on the structural basis of substrate promiscuity and the catalytic mechanism involved in the formation of flavonoid C-glycosides. R271 was a key amino acid residue site that sustained the catalytic reaction. The smaller binding pocket resulted in the production of new O-glycosides and the reduction of C-glycosides. This highlighted the importance of the binding pocket in determining whether C-glycosides or O-glycosides were produced.

Conclusions: The findings suggest that UGT708S6 holds promise as a new glycosyltransferase for synthesizing flavonoid glycosides and offer valuable insights for further understanding the catalytic mechanisms of flavonoid glycosyltransferases.

Cold atmospheric pressure plasma (CAP) has garnered significant attention in recent years for its potential applications in biomedical, environmental, and agricultural fields. Cold plasma treatment exhibits a variety of effects in agricultural applications, including impacts on seed germination and seedling growth; however, further research is required. Soybean serves as a fundamental source of nutrients for both animals and humans. Soybean seeds possess impermeable and thick testae, which results in prolonged germination times and suboptimal germination rates. The soybeans exhibit low uniformity. As a result, poor crop establishment and yield reduction are inevitable outcomes. Therefore, the purpose of this study was to examine the effects of Iranian soybean cultivars, such as Sari, Saba, Arian, Katoul, and Williams, on seedling growth properties, seed germination, and antioxidant enzyme activity, using argon at time intervals of 30, 60, 180, 300, and 420 s. Cold plasma treatment significantly enhanced germination potential from 1.18 to 66.97%, germination index from 0.50 to 60.09%, germination rate from 1.78 to 32.17%, seedling length from 2.70 cm to 78.13 cm, root length from 2.87 cm to 56.13 cm, and seedling dry weight from 1.80 g to 36.63 g. Additionally, CAT activity increased from 0.88- to 4.40-fold, SOD activity from 0.86- to 5.89-fold, and APX activities from 0.40- to 4.01-fold compared to the control treatment. The findings indicated that the samples exhibited optimal results at treatment durations of 60 and 180 s. The influence of plasma on the antioxidant responses of seedlings, seed germination, and growth characteristics was contingent upon the duration of treatment. Cold plasma, when applied for an appropriate duration, may enhance soybean seedling growth characteristics and seed germination.

Pathogenic fungi employ numerous strategies to colonize plants, infect them, reduce crop yield and quality, and cause significant losses in agricultural production. The increasing use of chemical pesticides has led to various ecological and environmental issues, including the emergence of resistant weeds, soil compaction, and water pollution, all negatively impacting agricultural sustainability. Additionally, the extensive development of synthetic fungicides has adverse effects on animal and human health, prompting the exploration of alternative approaches and green strategies for phytopathogen control. Microorganisms living in sponges represent a promising source of novel bioactive secondary metabolites, potentially useful in developing new nematicidal and antimicrobial agents. This study focuses on extracting bioactive compounds from endosymbiotic bacteria associated with the marine sponge Hyrtios erect sp. (collected from NIOF Station, Hurghada, Red Sea, Egypt) using various organic solvents. Bacillus sp. was isolated and identified through 16 S rRNA gene sequencing. The biocidal activity of Bacillus gotheilii MSB1 extracts was screened against plant pathogenic bacteria, fungi, and nematodes. The n-butanol extract showed significant potential as a biological fungicide against Alternaria alternata and Fusarium oxysporum. Both n-hexane and ethyl acetate extracts exhibited negative impacts against the plant pathogenic bacteria Erwinia carotovora and Ralstonia solanacearum, whereas the n-butanol extract had a positive effect. Regarding nematicidal activity, ethyl acetate and n-butanol extracts demonstrated in-vitro activity against the root-knot nematode Meloidogyne incognita, which causes serious vegetable crop diseases, but the n-hexane extract showed no positive effects. The findings suggest that bioactive compounds from endosymbiotic bacteria associated with marine sponges, particularly B. gotheilii MSB1, hold significant potential as alternative biological control agents against plant pathogens. The n-butanol extract, in particular, displayed promising biocidal activities against various plant pathogenic fungi, bacteria, and nematodes. These results support further exploration and development of such bioactive compounds as sustainable, environmentally friendly alternatives to synthetic pesticides and fungicides in agricultural practices.

Background: Exploration of whether circRNAs in the skin of systemic sclerosis (SSc) model mice interact with 4E-BP1 protein to mediate the mTOR signaling pathway to regulate SSc fibrosis is crucial to identify homologous human circRNAs as markers to guide the diagnosis and treatment of SSc.

Methods: C57BL/6 mice aged 6-8 weeks and weighing approximately 20 g were subcutaneously injected with bleomycin (BLM) to establish an SSc model. High-throughput sequencing was used to screen the differentially expressed circRNA in the skin of SSc model mice and control mice. RNA immunoprecipitation and RNA pulldown confirmed the interaction between circRNA and 4E-BP1 protein. SSc model mice were treated with empty plasmid (OE-NC), overexpression plasmid of mmu_circ_0005372 (OE-circ_0005372), interference plasmid of mmu_circ_0005372 (sh-circ5372), mutant plasmid of mmu_circ_0005372 (circ5372-MT), mTOR activator (MHY1485), mTOR inhibitor (omipalisib), or JAK1/2 inhibitor (ruxolitinib). Sections of mouse skin tissue were stained with Hematoxylin and eosin and Masson's stain. The collagen volume fraction (CVF) was calculated as CVF = area of blue collagen/total area with ImageJ. The correlation between homologous human circRNAs and clinical data was analyzed.

Results: Compared to the control group, 21,839 circRNAs were upregulated and 27, 946 circRNAs were downregulated in the skin tissue of mice in the SSc model group. Among them was mmu_circ_0005372, which is derived from the FZD3 gene, is closely related to fibrosis, and is involved in the mTOR signaling pathway. Hsa_circ_0136256 was identified as the homologous human circRNA of mmu_circ_0005372. RT-qPCR confirmed that the expression of mmu_circ_0005372 was significantly reduced in the skin tissue of SSc mice, and the expression of hsa_circ_0136256 was significantly reduced in the peripheral blood mononuclear cells of patients with SSc. The interaction between mmu_circ_0005372 and 4E-BP1 protein was inhibited in the skin tissue of SSc model mice. The results showed that the CVF of OE-circ_0005372 group was significantly lower than that of the sh-circ5372, circ5372-MT, and MHY1485 groups, indicating that OE-circ5372 significantly improved skin fibrosis in the SSc mice. ROC curve analysis was performed on hsa_circ_0136256 (AUC = 0.719, P = 0.035). The expression of hsa_circ_0136256 was negatively correlated with COL IV, RDW-SD, and RDW-CV, and positively correlated with VC, PLT, and PCT. The results suggested that hsa_circ_0136256 may have important roles in the clinical diagnosis of SSc.

Conclusion: Mmu_circ_0005372 and homologous human hsa_circ_0136256 may be biomarkers and therapeutic targets for SSc fibrosis.

Background: Vitamin B₁₂ is a crucial B-group vitamin, first isolated from the liver due to its role in combating pernicious anemia. It is distinguished by its unique and complex structure, which makes its chemical synthesis challenging and expensive. Consequently, vitamin B₁₂ is alternatively obtained through microbial fermentations. Molasses, an affordable and safe agro-industrial waste, can be used as a carbon source for vitamin B₁₂ production, offering a cost-effective alternative to expensive sugars in the production medium.

Results: A total of 87 yeast, actinomycete, and bacterial isolates were screened for vitamin B₁₂ production, with 15 isolates showing high productivity. Bacillus isolates were selected for further analysis using MALDI-TOF and molecular identification. These isolates were identified as four strains of Bacillus subtilis (MZ08, JT10, BY11, and JT17), one strains of Bacillus sp. (CB09), and one strain of Peribacillus acanthi (MZ01). Genetic circuits associated with vitamin B₁₂ production were demonstrated in a closely related strain of Peribacillus acanthi MZ01 strain. Three strains (MZ01, MZ08, and JT17) were selected for further evaluation of vitamin B₁₂ productivity under different sugar types (glucose, sucrose, fructose, lactose, and galactose) and varying inoculum sizes. The inoculum size significantly impacted vitamin B₁₂ production, with an increase from 5 to 10% enhancing yields. The ability of the strains to produce vitamin B₁₂ varied depending on the type of sugar used. Peribacillus acanthi MZ01 strain showed the highest productivity and subsequently, selected for optimizing vitamin B₁₂ production conditions using response surface methodology. Furthermore, the optimized conditions were then applied to molasses-based medium to achieve high vitamin B₁₂ yields by MZ01 strain.

Conclusion: In this study, Peribacillus acanthi was characterized for the first time as a vitamin B₁₂ producer, demonstrating high productivity among various tested strains. The optimization of production conditions using response surface methodology, further enhanced vitamin B₁₂ yields, showcasing the strain's efficiency in microbial fermentations. This research also highlights the potential of using molasses as a cost-effective alternative carbon source, significantly reducing production costs.

Background: Microbial melanins possess a broad spectrum of biological activities. However, there is little understanding of their neuroprotective and neuronal cell differentiation properties. This study aimed to extract, purify, and modify melanins from two medicinal fungi (Daedaleopsis tricolor and Fomes fomentarius), and to evaluate their antioxidant activity, as well as their cell protective ability against neurotoxins. In addition, the study also investigated the feasibility of combining melanins or modified melanins with retinoic acid (RA) to induce neuronal differentiation.

Methods: Melanin was extracted and purified using alkaline acid-based methods. Antioxidant activities and neuroprotective effects were evaluated using the DPPH (1,1-diphenyl-2-picrylhydrazyl) and MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assays, respectively. In addition, morphological changes of SH-SY5Y cells were recorded by using a Pannoramic MIDI scanner.

Results: All melanins and arginine-modified melanins displayed mild DPPH scavenging activities, which were statistically lower than that of ascorbic acid (p < 0.05). In terms of neuroprotection, both melanins and arginine-modified melanins exhibited significant cell protection against H₂O₂ after 24 h exposure (p < 0.05). Notably, there is no significant difference between F. fomentarius melanin and its modified form as they both increased cell viability by about 20%. Contrarily, while D. tricolor melanin enhanced the cell viability with 16%, its modified form increased the cell viability with 21%. These activities, however, are significantly lower than the positive control (N-acetylcysteine, p < 0.05). Regarding MPTP, only the arginine-modified melanins of the two fungi significantly protected the cells after 24 h exposure to the toxin (p < 0.05). Specifically, F. fomentarius and D. tricolor modified melanins enhanced the cell viability with 10.2% and 11.1%, respectively, whereas that of the positive control was 13.2%. Interestingly, combining RA (10 µM) with 20 µg/mL of either F. fomentarius, or especially D. tricolor arginine-modified melanin, significantly promoted neuroblastoma cell differentiation into mature neuronal cells compared to using RA alone (p < 0.05).

Conclusions: The arginine-modified melanins of D. tricolor and F. fomentarius have potential for neuroprotection against Parkinsonian neurotoxins. In addition, the arginine-modified melanin of D. tricolor may serve as an excellent material for research in neuroblastoma treatment.

Background: The primary indication of infertility is the incapacity to conceive, and in females, the majority of instances of female infertility stem from ovulation disorders. This study evaluated the female fertility-enhancing effects and safety of aqueous leaf extract of Brillantaisia patula (ALEBP) in a cyclophosphamide (CYP) model of sterility in Wistar rats.

Method: Sixty-six female rats randomly allotted to six groups (n = 11) were administered with the appropriate regimen for 21 days and then mated with male rats. Group 1 (control) received distilled water. Groups 2-6 were treated with a single dose (200 mgkg^- 1 body weight) of cyclophosphamide intraperitoneally and, in addition, received the same volume (0.5 mL) of distilled water, 18, 36, 72 mgkg^- 1 body weight of ALEBP and 200 mg per body weight of vitamin C orally. Mating lasted 11 days; on day 20, the female Wistar rats were sacrificed. Data were analysed using One-way Analysis of Variance (ANOVA) followed by Dunett's posthoc analysis, and GraphPad (at p < 0.05).

Results: Results herein showed that ALEBP significantly (p < 0.05) increased the diminution in activities/levels of glutathione peroxidase (GPx), reduced glutathione (GSH), total antioxidant capacity (TAC), cholesterol, alkaline phosphatase (ALP), acid phosphatase (ACP), estrogen (ES), and luteinising hormone (LH) induced by cyclophosphamide. ALEBP further reversed the increased level of malondialdehyde (MDA), tumour necrosis factor-α (TNFα), interleukin 8 (IL-8), and follicle-stimulating hormone (FSH) caused by cyclophosphamide (p < 0.05). In addition, ALEBP, while it significantly increased the cyclophosphamide-induced reduction in the number of implantations in each animal, the total number of viable fetuses, the total number of corpora lutea, and the fertility index, also significantly reduced the number of fetal resorptions in each animal and pre-implantation loss that was increased by cyclophosphamide. Moreover, the cyclophosphamide-induced degenerative and necrotic changes in the ovarian cells and uterus were reversed by ALEBP.

Conclusions: Considered as a whole, the aqueous leaf extract of Brillantaisia patula reversed oxidative stress and inflammatory side effects of cyclophosphamide, preserving ovarian function and fertility in the rats. This may suggest its exploration as a safe agent against toxic side effects of chemotherapy and fertility-related disorders of the uterus and ovary.

The study's goals are to fabricate PLGA nanoparticles (PNPs) loaded with apigenin (AP) and adenosine (AD) using a microfluidic preparation method to a standard emulsification method and investigate the possible heart-protective effects of AP-AD PNPs made using the emulsification method. Compared to microfluidics, the emulsification method fabricated small-size nanoparticles, which are better at encapsulating drugs, retaining more drugs, and having a low viscosity for the myocardial infarction (MI) injection. TheMI model was developed using SD rats injected under the skin with 85 mg/kg doxorubicin (DOX) for 2 days. The metabolic results showed that our AP-AD PNPs accelerated the blood flow in rats with MI, which increased the amounts of AP and AD in the circulatory system. This led to significant improvements in the cardiac index and lower amounts of AST, LDH, and CK in the blood. A histopathological study using Hematoxylin&eosin, and TUNEL staining showed that cardiac function had improved and apoptosis had decreased. Moreover, tests that checked the amounts of IL-6, TNF-α, NO, GSH, MDA, and SOD showed that AP-AD PNPs may help treat MI by reducing oxidative stress and inflammation, making it a potentially useful therapeutic approach.

This work examined the antibacterial and antibiofilm properties of alginate/collagen nanoparticles containing limonene. The multi-drug resistant (MDR) strains were screened, and the morphological features of the produced nanoparticles were determined utilizing SEM, DLS, and FTIR. Additionally, the encapsulation effectiveness, stability, and drug release were assessed. The levels of OmpA and Bap biofilm genes were assessed using qRT-PCR. At the same time, the antibacterial and cytotoxic activities of the nanoparticles were evaluated using well diffusion and MTT techniques, respectively. LAC nanoparticles measuring 300 ± 9.6 nm in size, 83.64 ± 0.19% encapsulation efficiency, and 60-day stability at 4 °C were synthesized. The biological investigation demonstrated that LAC nanoparticles had potent antibacterial capabilities. This was shown by their ability to significantly decrease the transcription of OmpA and Bap biofilm genes at a statistically significant level of p ≤ 0.05. The nanoparticles exhibited reduced antibiotic resistance compared to free limonene and alginate/collagen. Compared to limonene, LAC nanoparticles exhibited negligible cytotoxicity against HEK-293 at doses ranging from 1.56 to 100 µg/mL (p ≤ 0.01). The findings underscore the potential of LAC nanoparticles as a breakthrough in the fight against highly resistant pathogens. The potent antibacterial effects of LAC nanoparticles versus Acinetobacter baumannii (A. baumannii) MDR strains, considered highly resistant pathogens of significant concern, could inspire new strategies in antibacterial research.

Background: Natural pigments are becoming more significant because of the rising cost of raw materials, pollution, and the complexity of synthetic pigments. Compared to synthetic pigments, natural pigments exhibit antimicrobial properties and is less allergic. Pigments from microbial sources could easily be obtained in an inexpensive culture media, produced in high yields, and microbes are capable of producing different colored pigments. Searching for new sources for natural pigments to replace synthetic ones in food applications has become an urgent necessity, but the instability of these compounds is sometimes considered one of the obstacles that reduce their application. Encapsulation provides an ideal solution for natural dye protection through a controlled release strategy. Thus, this study aims at isolation of several soil fungi and subsequent screening their pigment production ability. The chosen pigment-producing fungal strain underwent full identification. The produced pigment was extracted with ethyl acetate and estimated spectrophotometrically. As there is a necessity to obtain a high pigment yield for efficient industrial application, the best production medium was tested, optimum conditions for maximum dye production were also investigated through the response surface methodology, and gamma irradiation was also employed to enhance the fungal productivity. Encapsulation of the produced pigment into chitosan microsphere was tested. The pigment release under different pH conditions was also investigated.

Results: A new strain, Fusarium verticillioides AUMC 15934 was chosen and identified for a violet pigment production process. Out of four different media studied, the tested strain grew well on potato dextrose broth medium. Optimum conditions are initial medium pH 8, 25 °C-incubation temperature, and for 15-day incubation period under shaking state. Moreover, a 400 Gy irradiation dose enhanced the pigment production. Chitosan microsphere loaded by the pigment was successfully prepared and characterized by infrared spectroscopy and scanning electron microscopy.

Conclusion: This irradiated Fusarium strain provides a more economically favorable source for production of a natural violet dye with an optimum productivity, enhanced yield, and improved properties (such as, enhanced stability, controlled release, and bioaccessibility) by encapsulation with chitosan for efficient application in food industry.